Measurement of daily cholesterol synthesis rates in man by assay of the fractional conversion of mevalonic acid to cholesterol. A significant correlation has been found in man between total daily cholesterol synthesis rates as determined by sterol balance measurements and the fraction of intravenously administered R-[5-14C]mevalonic acid converted to cholesterol. In 30 studies it was found that the mean daily cholesterol synthesis rates estimated by sterol balance measurements ranged from 395 to 3047 mg/day, whereas the fractional conversion of mevalonate to cholesterol varied from 0.28 to 0.99. The two parameters correlated with a coefficient of 0.87, P less than 0.001. This method for estimating cholesterol synthesis rates requires low doses of radioisotopic materials (25 muCi of [14C]mevalonate and 5 muCi of [3H]cholesterol) and less than 1 hr of the patient's time; it can be repeated at intervals of 3 weeks and reflects cholesterol synthesis over a short period of time.


Authentic beta-globin mRNA sequences in homozygous betaO-thalassemia. In a patient with homozygous betaO-thalassemia in whom studies of reticulocyte hemoglobin synthesis showed no beta-globin chain synthesis in vivo and in vitro, molecular hybridization studies revealed RNA sequences complementary to beta-globin cDNA. The fact that these sequences were authentic beta-globin mRNA was shown by fingerprint analysis of T1 ribonuclease-digested mRNA and by sequencing of oligonucleotides unique to beta-globin mRNA. The beta-mRNA that failed to direct beta-globin chain synthesis was not detectably shortened or degraded and contained poly(A) sequences.


Variation in ability of measles virus plaque progeny to induce interferon. Plaque progeny of three interferon (IF)-inducing strains of measles virus (Edmonston, Schwarz, and CC) were examined for ability to induce IF in BSC-1 cells. Only after passage in Vero cells did any of the Edmonston progeny induce IF. The vast majority of plaque progeny selected from the Schwarz strain induced IF, even though this virus was originally derived from the Edmonston strain. This property was retained even after serial plaque purification of the progeny. However, the Schwarz-derived CC strain consisted of a population generally unable to induce IF. Stocks grown from both Edmonston and CC plaques demonstrating the IF+ phenotype maintained this characteristic as a whole, but it was not a property that was inherited by all progeny in the stocks. Levels of IF induced were approximately the same for all strains, even though the proportion of inducing progeny varied markedly among them. These noninducing variants appeared to be normal, fully infectious measles virions. The results suggest that induction of IF by measles virus is at least partially under the genetic control of the virus.


Nonlinear analysis of cat retinal ganglion cells in the frequency domain. We have analyzed the responses of cat retinal ganglion cells to luminosity gratings that are modulated in time by a sum of sinusoids. A judicious choice of the component temporal frequencies permits a separation of the linear and second-order nonlinear components. Y cell responses show harmonic generation and intermodulation distortion over a wide frequency range. These nonlinear components predominate over the linear components for certain types of spatial stimuli. Nonlinear components in X cells are greatly diminished in comparison. The character of the nonlinear responses provides strong constraints on prospective models for the nonlinear pathway of the Y cell.


Modulation of acetylcholine receptor by antibody against the receptor. Antibody against acetylcholine receptor induces an increase in the rate of degradation of acetylcholine receptors on a mouse cell line (BC(3)H-1) and cultured rat skeletal muscle. The increased rate of degradation results in a lowered density of acetylcholine receptors on muscle membrane and a lowered sensitivity to iontophoretically applied acetylcholine. The modulation of acetylcholine receptor is energy, temperature, and time dependent and may be related to antigenic modulation found in other systems. Acetylcholine noise analysis demonstrates that antibody against acetylcholine receptor reduces the channel mean conductance and mean open time slightly. It is concluded that antibody binds to the acetylcholine receptor, impairs its function, and induces receptor degradation. This results in a lowered density of acetylcholine receptor and a lowered sensitivity to acetylcholine. Patients with myasthenia gravis have antibodies to their acetylcholine receptor in their serum. Antigenic modulation of receptor in the muscle of patients with myasthenia gravis could contribute to the observed decrease in amplitudes of miniature endplate potentials and in muscle acetylcholine sensitivity, and the symptoms of muscular weakness.


Lithium efflux through the Na/K pump in human erythrocytes. ACTIVE LI EFFLUX FROM HUMAN ERYTHROCYTES WAS SHOWN TO BE MEDIATED BY THE NA/K PUMP: (i) intracellular Li (Li(c)) activated ouabain-sensitive K influx, and (ii) a portion of the Li efflux required external K and was inhibited by ouabain. In activating K influx, Li(c) interacts with the pump like Na rather than like K-depleting the cells of orthophosphate inhibited activation of K influx by intracellular K (K/K exchange) but did not inhibit Li-activated K influx. (To show these interactions of Li(c) with the Na/K pump, p-chloromercuribenzenesulfonate or nystatin was used to allow replacement of intracellular Na and K with Li and choline.) From kinetic studies of the pump, it was shown that the apparent affinity of the intracellular aspect of the Na/K pump for Li was an order of magnitude less than that for Na. From simultaneous measurements of ouabain-sensitive net fluxes of Li and K in Na-free cells, it was shown that the pump-mediated K influx and Li efflux were coupled. The stoichiometry of the coupling ratio was close to 1:1 for Li:K, different from the coupling ratio of 3:2 for Na:K in the pump's normal mode of operation. It had been shown previously that the Na/K pump in human erythrocytes mediates active Li influx. Because it also mediates active Li efflux, the molecular mechanisms for distinguishing between Na and K must be qualitatively different at the internal and external aspects of the pump. The possible relevance of the results of this study to manic depressive illness and Li therapy is discussed.


[Increased occurrence of mycoplasmal pneumonia: radiologic appearance and observation of the development of the disease in children (author's transl)]. The epidemic occurrence of mycoplasmal pneumonia in children was reported. It composed 8% of all cases of pneumonia during 1975 occurring in the area served by the University Pediatric Hospital in Giessen. It should be noted that the cases were distributed throughout the year and that one fourth of the patients were small children. The diversity of the radiologic appearance with primarily interstitial-alveolar lesions in the lungs was explained in more detail. Observations of the course of the disease indicate that the illness can be recurrent; the course can be complicated as a result of immunosuppression through a primary illness which is already present, in this case an acute lymphoblastic leukemia.


Bacteria in cavities beneath intermediary base materials. The ability of six different intermediary base materials to prevent bacterial entrance beneath silicate cement fillings was investigated in vivo in primary molars. After an observation period of 1 month, bacteria were found on the pulpal wall in two out of 10 cavities beneath Fluoritec and four out of 10 cavities beneath Durelon solid mixed, De Trey phosphate cement solid or creamy mixed. Beneath the intermediary base materials Dycal, zinc oxide-eugenol cement, Dropsin and Durelon creamy mixed, no bacteria were found. In cavities filled with silicate cement or silver amalgam only, bacteria were observed in nine out of 10 and in five out of 10 cavities, respectively.


Binding of dyes to chlorhexidine-treated hydroxyapatite. The binding of some selected food dyes to hydroxyapatite with and without a coating of chlorhexidine was studied. The apatite had bound 0.6 mumol chlorhexidine per g dry weight. The bound chlorhexidine was in equilibrium with a free concentration of 115 microgram ml (128 micron). The dyes investigated were brilliant blue (FD&C Blue No. 1), indigo carmine (FD&C Blue No. 2), tartrazine (FD&C Yellow No. 5), sunset yellow (FD&C Yellow No. 6), amaranth (FD&C Red No. 2), and riboflavin. Riboflavin did not bind to either chlorhexidine-treated apatite or untreated apatite, whereas the other dyes showed a considerable affinity for chlorhexidine-treated apatite as compared with untreated apatite. Because the dyes with binding ability possess two or three acidic groups, and because riboflavin has none, it was suggested that the binding of the dyes is mediated by an interaction between the anionic groups of the dye molecules and the cationic groups of the chlorhexidine molecules. The results are discussed and related to the formation of the brownish discolorations seen on the teeth of patients using chlorhexidine mouthrinses. A mechanism to explain the development of tooth stains is proposed.


Lipidhistochemical and microradiographic study of distribution of lipids in relation to mineral content in dentin caries. Fifteen human molars were investigated using lipidhistochemical and microradiographic methods. A peripheral necrotic and totally decalcified part of the carious lesion revealed a markedly positive staining reaction for sphingomyelin, sulfatides, cholesterol- and/or triglyceride-esters. The reaction was probably conditioned by the presence of debris and plaque within this area. Pulpally and immediately below the necrotic zone, an area of demineralization was found which on the microradiographs appeared as a radiolucent zone. The zone showed a mineral gradient with an increasing mineral content towards the pulp. In the zone of demineralization a positive reaction occurred for sphingomyelin decreasing in a pulpal direction with increasing mineral content. A weakly positive reaction for cholesterol- and/or triglyceride-esters was also detected but only in the most pulpal part of the zone of demineralization; the intensity of the staining reaction was comparable to that found in normal dentin. In those areas which were represented by a sclerotized, radiopaque zone, only a very weak reaction for sphingomyelin, cholesterol-and/or triglyceride-esters could be observed of the same staining intensity as in normal dentin. The region between the lesion and the pulp showed the same staining intensity as normal dentin.


Quantitative observation on teeth during calcium deprivation in rats. Adult female rats were subjected to severe calcium deprivation by feeding them a calcium-deficient diet containing oxalate (Group A). Furthermore, pregnant and lactating animals were subjected to the same diet (Group B). The mandibular teeth were collected for ash determination and for linear measurements. The ash content of the growing incisors was only slightly reduced in Group A, while the reduction in Group B was 27%. Linear measurements demonstrated that the outer dimensions of the incisors were not affected by the calcium-depriving regimen in either group, while the inner dimensions (pulp cavity) were considerably increased in Group B due to reduced thickness of the dentin mantle. The daily dentin apposition in Group A did not deviate much from the control values, while in Group B it was severely reduced. The thickness of incisor enamel was unaffected by the calcium-depriving regimen. The ash content of the molars was normal in Group A, but slightly reduced in Group B.


Enzymatic iodination of salivary proteins by the 125I-lactoperoxidase system. Purified milk lactoperoxidase and endogenous human salivary peroxidase were used to label the proteins of whole mouth saliva with [125I]iodide. The proteins were then analyzed by isoelectric focusing or they were subjected to one-dimensional polyacrylamide gel electrophoresis at pH 8.4. The radioactivity of the resolved protein fractions was determined. There were three to four major and four to five minor areas of radioactivity which were carried together with more or less distinctive protein fractions. Amylase and albumin were shown to be the most effective in binding [125I]iodide. No significant differences were observed in the iodination patterns of salivary proteins iodinated in the presence of endogenous saliva peroxidase and those iodinated in the presence of added milk lactoperoxidase. Hydrogen peroxide was necessary for iodination to take place. The significance of iodoproteins and the role of salivary peroxidases in the nonthyroidal metabolism of iodine are discussed.


A longitudinal study on the effect of unilateral extraction of primary molars. The effect of unilateral extraction of the first or second primary molar on space conditions, need for orthodontic treatment, and eruption stage of permanent canines and second molars has been studied longitudinally in two groups. In Group 1 the first primary molar had been extracted early in 13 cases in the maxilla and in 14 cases in the mandible. In Group 2 the corresponding figures for the second primary molar were 14 and 24 for the maxilla and mandible, respectively. The space on the extraction side in Group 1 was significantly less than on the control side at the age of 9 but not at the age of 13. In Group 2 there was significantly less space on the extraction side than on the control side at the two registration ages (10.5 and 12 years). Need for orthodontic treatment was low in Group 1 and high in Group 2. As for eruption stage of permanent canines and second molars, no significant differences were found between the extraction side and the control side in the two groups.


[Synoviorthesis of the knee with osmic acid (OsO4). Results at mid-term]. Synoviorthesis of the knee joint with OsO4 is a simple procedure with few short or long term side effects. The substance used is inexpensive and easy to handle. All studies published so far have confirmed its suitability in the treatment of synovitis of the knee and various other joints. The initial good results deteriorate steadily, primarily in the first year following injection. However, intra-articular administration of OsO4 may be repeated without risk, and achieves as good results as the first synoviorthesis. The less advanced the lesions and the less active clinically and biologically the systemic manifestations, the better the results. Osmic acid does not appear to damage the joint either radiologically or functionally. The effect of OsO4, although probably shorter in duration, is comparable to that of yttrium-90, with the additional advantage that it can be used in young patients. 100 mg (5 ml of 2% solution) can be considered the optimal dose. Synoviorthesis with osmic acid can be performed before going on to surgical synovectomy. Synoviorthesis with osmic acid is ineffective in the treatment of gonarthrosis.


Dental caries and restorations in teenagers. I. Index and score system for radiographic studies of proximal surfaces. An index and a score system for radiographical longitudinal studies of caries progression on proximal tooth surfaces are presented and compared with the DF-surface system. Generally, a good correlation between DF-surface differences and scores was found in a three-year study on teenagers. However, the score system seems to forward better means for a detailed study of the individual.


Dental caries and restorations in teenargers. II. A longitudinal radiographic study of the caries increment of proximal surfaces among urban teenagers in Sweden. Within a group of 16 year old school children leaving the regular school dental care, the number of carious lesions and fillings in proximal tooth surfaces was radiographically studied, using an index system. Three years later, the same individuals were re-examined. The results showed that intact surfaces and surfaces with small carious lesions were more resistant to change than others. A minority of the individuals was found to be responsible for a majority of the lesions established during the three year interval. Generally, the progress of caries was slow.


Masseter motor pause frequency as related to different bolus sizes. The frequency of motor pauses in the masseter EMG is recorded for different bolus sizes of chewing gum on ten dentate subjects. The bolus sizes were from one two five tables of chewing gum, and the instructions to the subjects were to chew normally. No correlation between bolus size and frequency of motor pauses was found.


Specific conditions of distress in the dental situation. The general feeling of distress in the dental situation has been studied in 60 female dental patients and correlated to the following variables: Experimentally evaluated sensitivity to pain, self-rating and the dentist's rating of sensitivity to pain, the pain-threshold value in the teeth, the need of local anesthesia, extraversion-introversion, neuroticism, and some percept-genetic psychological measures of adaptive behavior. The subjects have also answered a questionnaire for grading their distress in regard to different aspects of the treatment-situation, which were combined into eight groups using factor analysis and then correlated to the general distress. The variables having a significant relation to distress in the dental situation were: the dentist's rating of the patient's sensitivity, the need of anesthesia, four groups of treatment-components and two of the percept-genetic measures. There was also a certain relation to the pain threshold in the teeth.


[Contribution to the discussion about the induction of tumors by ionizing radiation (author's transl)]. The authors describe six observations of malignant tumors which had appeared in the region of the irradiation fields after a period of 11 to 51 years following to a radiotherapy. The doses were between approximately 2000 and 9000 R resp. rd. The individual tumors were: one osteogenic sarcoma, one chondrosarcoma, two fibrosarcomas, one lymphangio-hemangio-sarcoma and one basal cell carcinoma. According to the present state of our knowledge about the induction of tumors by ionizing radiation, we presume that no threshold dose does exist and that the danger of a tumor induction increases with the dose. The function of the tumor induction is still in general discussion.


[Clinical and microstructural comparative studies on fillings made from gallium-tin-nickel alloys and from silver-tin amalgam]. The filling material "Gallodent" has been clinically controlled for a period of one year. Scanning electron microscopic examinnations revealed greater surface porosity with negligible microleakage and better marginal adaptation as compared to amalgam. Early corrosion phenomena required re-polishing every three months. This disadvantage and the brittleness of the gallium-tin-nickel alloys hinder, at present, these alloys from superseding high-silver amalgams.


[Periodontol problems in the mixed dentition]. The authors studied the periodontal and oral hygiene conditions in 343 children from the children's town of Fót. They observed a not too great increase in gingivitis intensity in the mixed dentition which is very seldom seen under physiological conditions of the change to permanent dentition; but which occurs frequently in individuals with badly decayed milk molars associated with poor oral hygiene and impaired masticatory function.


[Specialization in periodontology].

[Specialization in periodontology]. In addition to the demand that periodontal therapy should be the task of any stomatologist, the considerable morbidity and the aetiopathological special features of periodontal diseases call for specialists. Periodontal basic care and specialized therapy easy to delimitate. The specified stomatological curriculum allows for the demands on periodontology; it is imperative to enforce them in education and continuing education.


[Diseases of the temporomandibular joint--a clinical statistical study]. Affections of the temporo-mandibular joint are rare clinical pictures; but their incidence is ever increasing. Their scientific elucidation is imperative, especially since discrepancies concerning the terminology, definitions and practical treatment methods hinder uniform conceptions from becoming effective. From the clinico-statistical analysis of 587 cases the authors deduce statements regarding the frequency of the different diagnosis groups and the distribution according to age, sex and side affected. The distribution according to occupational groups is also presented. A uniform nomenclature (according to Birke) of the affections of the temporo-mandibular joint being now available, the next step must be to dilimitate the validity of different diagnostic methods and to arrive at clear-cut treatment directives, interdisciplinary cooperation being absolutely necessary.


[Studies on the uses of the electronic image evaluating device "Densitron" for the evaluation of dental radiographs. III. Standardisation in densitometry]. The authors outline in two papers to what extent the interpretability of a radiograph is changed when converted by means of the Densitron. They confined themselves to the interpretation of dental films and panoramic radiographs. For reasons of clinical interest, particular attention was paid in dental films on localized processes (such as dental caries), and in panoramic radiographs on possible bone diseases as a sequel or concomitant affection in case of renal insufficiency, diabetes mellitus and hyperthyreosis.


[Caries prevention by means of local fluoride application]. The topical application of fluoride has developed into an effective health-saving measure for the individual and the collective prevention of caries. A reduction in caries increment of 30 to 40% may be expected. With reference to the mode of action of topically applied fluorides on dental enamel and plaques, methods and preparations are recommended for acceptance in the framework of socialist health protection.


[Comparative studies on the breaking strength of tissue adhesives of the butylcyanoacrylate type]. Four tissue adhesives of the butylcyano-acrylate type were tested for breaking strength. The addition of dyes and stabilizers results in an increase in breaking strength. Adhesives coloured with an anthraquinone dye and stabilized with SO2 significantly surpass in breaking strength adhesives that are only coloured or stabilized. Fiomed II (coloured, stabilized with SO2) yields significantly (at P=0.001) better values than Histoacryl blue. Addition of the dye alone seems to exert a better effect on breaking strength than addition of the stabilizer alone. As evidenced by our results, the breaking strength is in the order: 1. Fiomed II (coloured, stabilized with SO2), 2. Histoacryl blue, 3. Fiomed III (coloured, without SO2), 4. Fiomed I (without dye, stabilized with SO2).


[Long-term experiences with surgery of large jaw cysts by the Nasteff-Rosenthal method]. Of a total of almost 200 patients operated upon by means of the Nasteff-Rosenthal method during the years 1962-1972, 80 could be re-examined. The results obtained show that this operating method stands the comparison with other techniques and that it may be recommended further on for the treatment of great cysts in the mandible as well as in the maxillae.


[Studies on the surgical approach in vital pulp excision in relation to the root canal cross section]. The authors examined in 38 teeth the condition of the pulp stump after vital extirpation of the pulp in relation to the cross-section of the  root canal. They found that the wound conditions could not be evaluated in 17 teeth as there was no pulp stump in the apical region. Relatively favourable conditions were seen in 11 teeth, which was achieved only in case of circular or oval cross-section of the root canal. These findings permit the conclusion that the state of the pulp stump after vital extirpation depends upon the anatomical conditions and the accuracy of the mechanical manipulation.


[Biodevelopmental and biostatistical aspects of the concept of normal values in the 1st and 2d dentition]. In conformity with the practice in other biological sciences, it is suggested to adopt in dentition chronology the double of the range around the mean as the range of normal. The great variance especially in the second dentition agrees with the variance of other developmental characteristics and must be considered to be typical of human development. The integration of dentition with the complex of the characteristics of physical and psychical development is advocated.


[The need for stomatological care in the light of an analysis of the frequency of stomatologic diseases]. The present paper deals with a method for determining the extent of stomatological care for the population of the GDR. The components "stomatological morbidity", "available amount of time" and "average amount of working time spent on each prosthetic/conservative service" are linked to determine the extent of stomatological care with regard to the three variants of prosthetic/conservative treatment. The calculation method is used to find out the optimal variant.


[How aware are our patients? A contribution to health education]. 821 new-admitted patients were examined to substantiate the present state of health-oriented modes of behaviour in the field of stomatology. 20% of the patients consulted for prophylactic reasons. 59% of the total of patients presenting with pain had been fully aware of their need for treatment prior to the acute event. Relationships between age and mode of behaviour and the significance of the family dentist are demonstrated.


The diagnostic usefulness of electron microscopy investigation of orbital embryonal rhabdomyosarcomas. The ultrastructural study of three malignant orbital tumors, only one of which was correctly diagnosed as embryonal rhabdomyosarcoma upon histologic examination, is reported. In all 3 cases electron microscopic investigation revealed the presence of rhabdomyoblasts. These are easily recognizable in one case in which the diagnosis was made on the basis of the optical microscopic study. The other two cases needed further tests to evince rhabdomyoblasts. The importance of an ultrastructural study for a histogenetic characterization of this kind of tumor is emphasized. As far as embryonal rhabdomyosarcomas are concerned the electron microscopic study is possible, and it gives useful results even when material fixed with routine histologic methods (formalin, Bouin's solution) are used.


Traumatic fibromyositis: a critical review of an enigmatic concept. Traumatic fibromyositis is not an inflammation; there is no fever, leukocytosis or increased sedimentation rate; electrical characteristics and serum enzyme levels are within normal limits, and there are no observable pathologic alterations, although they have been carefully searched for. Recent attempts to express the effects of muscular sprain or strain as a biochemical disturbance expressed in an unusual pattern of lactate dehydrogenase isoenzymes appear not only to be technically flawed but inconsistent with results of conventional enzyme studies on other muscle and interstitial inflammations. In the author's view, "traumatic" fibromyositis is no more than a verbal construct arrived at by adding an adjectival modifier to the old terms for idiopathic rheumatic disorders. An examination of the evolution of the concept of traumatic fibromyositis shows that it lacks validity as a clinical diagnosis and ought to be abandoned.


[Serum methotrexate determination by microbiological assay in patients receiving high-dosage methotrexate (author's transl)]. Microbiological assay according to Burchenal (modified by Mehta) is used for the determination of the serum methotrexate (MTX) level. Fifty cycles of high-dose MTX therapy were monitored in 11 patients with osteogenic sarcoma. The results showed close correlation with the clinical course of the therapy. The serum level of MTX was elevated in patients with symptoms of toxicity.


Intraperitoneal drain in cholelithiasis operations. 571 patients were operated on for cholelithiasis, 70 acute cases and 501 chronic ones. On 142 cases of the latter type choledochus exploration was performed, while on the others only simple cholecystectomy was carried out. Intraperitoneal drain in the form of a latex tube was used on all the acute cases except 4, on all who underwent choledochus exploration except 3, and on 254 of the 359 chronic cases on whom simple cholecystectomy was performed. The analysi of the material shows that the indications for intraperitoneal drainage are not very convincing after cholecystectomy at a chronic stage, considering the amount of fluid drawn via the intraperitoneal drain and the complications that arose. After choledochus exploration, however, intraperitoneal drain serves its purpose in connection with the removal of the choledochus drain. Intraperitoneal drain should therefore be used when choledochus has been explored. In routine cases it should not be removed until the choledochus drain has been withdrawn.


Pre-ovulatory plasma levels of 17beta-oestradiol (E2) and conception in patients treated with gonadotrophins. Twenty-six patients seeking advice for sterility were given courses of treatment with HMG-HCG. Ovarian maturation was followed by daily evaluation of plasma 17beta-oestradiol concentrations. HCG was administered as soon as 17beta-oestradiol levels reached 250 pg/ml. In a first group of 7 amenorrheic patients with lack of oestrogen activity, a pregnancy rate of 71.4% and an ovulation rate of 91.7% were achieved. In a second group of 5 amenorrheic patients showing evidence of oestrogen activity, a pregnancy rate of 80.0% and an ovulation rate of 100% were obtained. In a third group of 14 oligomenorrheic patients, the pregnancy rate attained 71.4% and the ovulation rate 96.9%. The overall pregnancy rate was 73.0%. With this procedure of monitoring HMG-HCG treatment by means of plasma 17beta-oestradiol levels, the multiple pregnancy rate reached only 11.7% and only one case of mild ovarian hyperstimulation was observed. Pre-ovulatory and pre-conceptional 17beta-oestradiol concentration were identical with those observed in spontaneous ovulatory cycles with or without conception.


Conception, contraception and misconception. Because of Dr. G. A. Overbeek's interest and contributions in the field of oral contraception a survey is given of present leads and developments in this area. It is concluded that contraceptive preparations known under names such as: once-a-month pill, morning-after pill and post-coitum pill, although desired, do not really exist at the moment. It is further expected that oral contraception based on the inhibition of ovulation will stay with us for many years to come. Better preparations, not exclusively containing oestrogen progestagen combinations but possibly including a non-hormonal pituitary inhibitor as well, might be developed. This will allow better control over the endometrium, and the unwanted effects of the presently used hormonal substances. It is likely that an implantation-inhibiting compound or an abortifacient which acts shortly after implantation will be found. With respect to oral contraception for males it is concluded that, although inhibition of spermatogenesis with drugs is possible, a satisfactory contraceptive treatment for men is not yet available.


The effect of chlorhexidine and some other detergents on the activity of dextransucrase from Streptococcus mutans. The inhibitory effect of chlorhexidine and other bis-biguanides on the formation of dental plaque is not fully understood. The present paper describes the effect of chlorhexidine and some selected detergents on the activity of dextransucrase (EC 2.4.1.5.), an enzyme involved in the formation of important components of dental plaque. All detergents examined exerted an inhibitory effect on dextransucrase activity, to some degree dependent on the presence of charged groups and their characters. The high concentrations of chlorhexidine necessary to inhibit dextransucrase activity seem to exclude the possibility that chlorhexidine exerts its plaque inhibiting effect by means of an effect on dextransucrase.


The effect of muscle function in discriminating thickness differences interocclusally and the duration of the perceptive memory. The thresholds in discriminating the thickness differences interocclusally were measured with three different mouth openings on subjects having natural dentitions. Also the duration of the perceptive memory was studied. The results showed that the functional activation or fatiguing of masticatory muscles and the degree of mouth opening affect size discrimination interocclusally. The ability to perceive thickness differences between the incisors was more accurate after 1 hour's chewing than normally. The trend was significant with 0.5 mm and 10 mm mouth openings (2 P less than 0.01) and highly significant with an 20 mm mouth opening (2 P less than 0.001). With a 20 mm mouth opening (2 P less than 0.01) and 10 mm mouth opening (2 P less than 0.05) size discrimination was less accurate after two hours' fatiguing chewing than after one hour's conventional chewing. After 30 seconds' forceful isometric contraction and with 20 mm mouth opening discrimination was more accurate than normally (2 P less than 0.01). The trend was the same with a 10 mm mouth opening, but no difference could be observed when the mouth opening was 0.5 mm. The memory tests showed that with a 0.5 mm mouth opening thickness differences of 0.3-0.5 mm were most commonly correctly perceived twenty-four hours later, but when the mouth openings were 10 and 20 mm an interval of only 1 min between the reference and test piece trial impaired the performance.


Intra-examiner reliability of epidemiologic registrations of malocclusion. Intra-examiner consistency in the recording of single traits of malocclusion according to a previously described method was assessed by duplicate registrations on study models of 292 children. The level of agreement was expressed by the consistency ratio and the phi coefficient. A high level of consistency was obtained for most of the malocclusion traits, and it was concluded that the method employed is appropriate also for analyses of interrelations between these traits.


Arthrosis and deviation in form in the temporomandibular joint. A macroscopic study on a human autopsy material. The right TMJ from 115 individuals, aged 1 day--93 years, were examined macroscopically regarding the occurrence of deviation in form and arthrosis in the three articulating joint components. The changes were classified according to extent. In addition, the depth of the arthrotic lesions was determined. Nearly half (48 of 102) of the adult TMJs revealed some form of change. No changes in the joint surfaces were noted from individuals under 20 years of age. Deviations in form occurred in 45 of the 48 affected joints and arthrosis in 24. The deviations in form were most common in the condyle while arthrotic lesions were noted mainly in the disk and temporal component of the joint. The changes were usually local in nature and located in the lateral one-third of the joint.


Contraction stresses of composite resin filling materials. The polymerization shrinkage of composite resin filling materials and the tensile stresses developed when the shrinkage is restrained were measured in an in vitro experiment. This allows an estimation to be made of the forces exerted upon the enamel walls of cavities filled with the resin in the acid etch technique. The results indicate that the stresses acting on the enamel are low compared to the tensile strength of the enamel.


Subjective symptoms in temporomandibular joint osteoarthrosis. Questionnaires about subjective symptoms were sent by post to 120 patients referred to the clinic for mandibular dysfunction. A group of 20 patients with crepitation of the temporomandibular joint (TMJ) and a group of 19 patients with palpatory tenderness of the TMJ were compared with a reference group of 29 patients for any difference in local subjective symptoms, frequency of headache and symptoms in other joints. The patients with TMJ crepitation, which were considered to have TMJ osteoarthrosis, were older and reported a higher frequency of grating sound from the TMJ than the patients in the reference group. The patients with palpatory tenderness of the TMJ reported a higher frequency of toothgrinding, more severe symptoms of mandibular dysfunction and a higher frequency of symptoms in the hand joints. No correlation was found between subjective symptoms of mandibular dysfunction and those of other joints. The results of the study indicate that patients with TMJ osteoarthrosis do not differ from other patients with mandibular dysfunction with respect to subjective symptoms and that subjective symptoms of mandibular dysfunction in general develop independently of those in other joints.


Echocardiographic assessment of left ventricular function during the injection of adriamycin. Echocardiography was used to evaluate left ventricular function in 8 children treated with adriamycin for malignant disease. Preejection period (PEP), left ventricular ejection time (LVET) and percent change in left ventricular internal dimension with systole (delta LVID) were measured before, during and immediately after 22 injections of adriamycin as well as 14 injections of other cytotoxic drugs and physiologic saline. No immediate effects on left ventricular function could be discerned. When functional parameters were evaluated longitudinally in patients with relatively higher cumulative doses of adriamycin, percent change in left ventricular internal dimension with systole showed some tendency to decrease, while the other parameters remained essentially unchanged.


The effect of immunotherapy with BCG on the development of radiostrontium (90Sr)-induced osteosarcoma. The development of radiostrontium-induced osteosarcoma was studied in BCG-treated and in untreated control mice. Within the observation period of 420 days after the administration of radiostrontium there was a total tumour-incidence of 89.5 and 90.5 per cent for the respective groups of animals. There was no statistically significant difference between the two groups, neither with regard to the time of the first roentgenographic appearance of the osteosarcoma, nor concerning the total tumour incidence , nor with regard to the distribution of the primary sites of the tumours. The tumours of the BCG-treated animals showed a clear tendency to a slower growth rate in comparison to that of the tumours in the control animals. This effect was probably immunological in nature. The mortality in osteosarcoma following radiostrontium administration, however, showed no significant difference between the two groups. Light microscopical and ultrastructural examination did not disclose any clear structural difference between the tumours from BCG-treated and untreated control animals.


The prevention of hypertension.

The prevention of hypertension. Our way to prevention is to find a list of traits known to be predictors of elevated blood pressure. This list of predictors offers means for the early identification of susceptibile persons. Years of experience in preventive work indicate that such identification is always useful for developing preventive programmes, since it gives a focus for action (5). Most of the predictors show possible ways in which action could be directed towards prevention of hypertension and reduction of elevated blood pressure. We will focus on salt, control of obesity, physical exercise, and meditation. We would like to discuss preventive aspects of hypertension and the possibility of treating with other methods than drugs.


Long-term aspects on essential hypertension. Hypertension has been found to imply a disease entity since the beginning of this century. Effective treatment available in the last two decades has changed the outlook remarkably, especially in malignant hypertension. There are more and more evidence that less severe forms of hypertension will benefit from keeping the blood pressure under control.


Haemodynamic effects of pindolol in hypertensive patients. Five men and five women, mean age 48 years, with hypertension in stages I or II of the WHO classification, were given preoral treatment with pindolol. The pindolol treatment lead a significant decrease in the systolic and diastolic blood pressure, at rest and during work both after 2 months and after 16 months treatment. Three mechanisms seem to be involved in the antihypertensive effect of pindolol: 1) a negative chronotropic effect on the heart, 2) a decrease in peripheral vascular resistance and 3) an increase in venous capacitance affecting the venous return. Comparison of the results after 2 and after 16 months of treatment suggests that a decrease in cardiac output is an early mechanism in the lowering of the blood pressure, while a decrease in vascular resistance seems to be more important after long-term treatment with pindolol.


Once a day treatment of hypertension.

Once a day treatment of hypertension. Two studies are presented on the possibility of treating hypertension with pindolol once daily. In the first one, patients already treated with multiple doses of pindolol, propranolol or alprenolol were shifted to single dose regime with pindolol, given in the morning. In most cases an adequate blood pressure control could be maintained on a dose of up to 20 mg pindolol. In the other study, previously untreated patients with mild to moderate hypertension were treated from the beginning with a single dose of pindolol. An adequate pressure control was also obtained in most of these patients with a dose not surpassing 20 mg pindolol once daily. In non-responders, the addition of a once daily dose of a diuretic resulted in an adequate pressure control. In both studies side-effects were few. The absence of sleep disturbances and beta-blocker induced bradycardia was particularly noteworthy.


Postoperative stabilization and intrusion of midface osteotomies with high-pull headgear. The two cases presented here illustrate advantageous uses of orthopedic-type craniomandibular headgear. Both cases demonstrate the use of headgear for postoperative cephalad movement of the maxilla. In Case 1 the use of headgear accomplished 6 mm. of anterior maxillary cephalad movement and 3.5 mm. of posterior maxillary cephalad movement. In Case 2 the use of postoperative headgear accomplished 8 mm. of anterior maxillary cephaled movement and 6.25 mm. of posterior maxillary cephalad movement. Table I indicates the duration of intermaxillary immobilization and the ensuing time that the cranial traction appliance was used. Fig. 10 illustrates the profile changes for Cases 1 and 2.


Force-extension characteristics of orthodontic elastics. The force-extension characteristics for a wide range of elastics were determined. It was found that (1) selection of elastics were determined. It was found that (1) selection of elastics based on 3 x lumen size will probably result in more force being generated than was previously reported, (2) there is very little difference seen in force-extension characteristics when the two manufacturers' elastics are compared, and (3) for experimental purposes, elastic testing can be done in the dry state for force-extension characteristic studies. This investigation has shown that stretching an orthodontic elastic to twice its original lumen diameter produces a force which better represents the manufacturer's expected value. Keeping these principles in mind, a more effective tooth-moving force can be realized, enabling the clinician to properly select orthodontic elastics for intra- and intermaxillary biomechanical procedures.


Accurate arch-discrepancy measurements.

Accurate arch-discrepancy measurements. A new technique for accurately measuring tooth-to-arch-length discrepancies according to the ideal arch form is discussed. The armamentarium for making these measurements is explained, and the technique is demonstrated. Clearly, this is an important part of orthodontic diagnosis, and there is a need for greater accuracy than that which techniques of the past have made possible.


A longitudinal study of dental arch growth. Changes in dental arch size and form were assessed by means of univariate and multivariate analysis in a longitudinal study of children between 2 and 10 years of age. The multivariate analysis served to assess the arches as a biologic whole rather than as a series of independent dimensions. Dental arches do not seem to undergo a steady rate of change up to the age of 10 years. In the arches anterior to the first permanent molars, peaks of growth occur between 2 and 3 years and 7 and 8 years in the maxilla, and between 2 and 3 years and 5 and 6 years in the mandible. In the arches, including the first permanent molars, peaks of growth occur between 6 and 8 years in the maxilla and between 9 and 10 years in the mandible.


Dentoalveolar morphology in relation to craniocervical posture. The associations between dentoalveolar morphology and the posture of the head and the cervical column were studied in a sample of 120 Danish male students aged 22-30 years. Two head positions were recorded on lateral cephalometric radiographs, one determined by the subjects's own feeling of a natural head balance (self balance position) and the other by the subject looking straight into a mirror (mirror position). Dentoalveolar morphology was described by 17 linear and angular variables and postural relationships by 18 angular variables. The position of the head in relation to the cervical column showed positive correlations with the anterior upper and lower dentoalveolar heights and with the inclinations of the upper and lower occlusal planes. These correlations were considered to reflect the dentoalveolar compensatory adaptation to the variation in vertical jaw relationship, which in a previous study had been found to be associated with craniocervical angulation. No associations were observed between craniocervical angulation and alveolar prognathism or incisor inclination. This was in accordance with the previous findings of a lack of associations between sagittal jaw relationship and craniocervical angulation.


The etiology and prediction of mandibular third molar impaction. 1. Skeletal Class II dental base relationship with a shorter, narrower, more acute angled madible was found in association with impacted third molars, compared with erupted teeth. 2. These differences were found at age 18+ years but were less obvious at age 10 to 11 years. 3. There was a reduced amount of mandibular growth in impacted third molar cases. 4. There was a slight tendency for impacted third molars to be larger than those which erupted. 5. The presence of a space between second and third molars in the early stages of development is not an indication that the third molar will erupt. 6. The developmental angulation of the third molar to the mandibular plane was higher in the impacted third molar group. 7. Accurate prediction of third molar impaction from radiographic measurements is not possible at age 10 to 11 years.


Proplast genioplasty: a retrospective study with treatment recommendations. The treatment results in 31 consecutive patients treated with Proplast for chin augmentation show good clinical succes with the implant. A critical analysis of treatment results reveals that attention to certain details of the preoperative evaluation, surgical technique, and postoperative care can make for impressive results. These facts are discussed.


The flomasta. A new anaesthetic ventilator. A new ventilator for use during anaesthesia is described. It operates as a minute-volume divider and derives its power from the energy stored in a distended reservoir bag. The unit is autoclavable, suitable for use with explosive anaesthetics and has a rational control system which avoids many of the hazards associated with other ventilators when the mode of ventilation is changed. The nature of the inspired gas mixture is known accurately because the internal volume of the ventilator is small and the system is non-rebreathing. The design of the exhaust system facilitates ventilation monitoring, the use of positive end-expiratory pressure and connection to ducted pollution-control systems.


Cases six years postretention.

Cases six years postretention. 1. The cuspid width is most likely to decrease after treatment (9 of 11) although on occasion a slight increase (2 of 11) was maintained. 2. The molar width is apt to decrease from the beginning of treatment through the postretention period. 3. The cephalometric measurements studied in this sample of good stable occlusions coincided with with the norms and ranges as used by R.M. 4. The age changes of the various cephalometric measurements also agreed with the age changes that R.M. utilize. 5. Lower arch crowding may be due to multiple factors of expanded cuspids, protrusive and labially inclined mandibular incisors, and late skeletal growth changes.


Factors of human skeletal craniofacial morphology. Thirty cephalometric measurements representing craniofacial depth, height, and width were obtained from lateral and posterior rediographs of 66 boys, 8 years of age. A multivariate factor analysis was performed on these measurements in an effort to locate specific areas of variability within the craniofacial complex. Twelve uncorrelated factors were extracted which account for 91% of the total variance and these were identified as: 1) retrognathic facial type, 2) anterior dentoalveolar height, 3) maxillary body length, 4) cranial base and facial width, 5) mandibular ramus height, 6) anterior maxillary body height, 7) mandibular length, 8) cranial vault height, 9) vertical position of the condyles, 10) cranial vault and clivus length, 11) bigonial width, and 12) cranial vault width.


The effect of central nervous system stimulants on Tourette syndrome. A survey of patients with  Tourette syndrome uncovered 32 who had been exposed to central nervous system stimulants. In 17 (53%) of these patients, symptoms were markedly accentuated by the drugs. Two patients whose Tourette syndrome developed suddenly when methylphenidate was administered are also reported.


Hydroxyurea in the prevention of the effects of leukostasis in acute leukemia. Hydroxyurea was administered orally to prevent the effects of leukostasis in adults with acute leukemia who had peripheral blast cell counts greater than 100,000/cu mm. A single oral dose of 50 to 100 mg/kg was given daily until the absolute blast cell count decreased to less than 100,000/cu mm. Hydroxyurea was effective in rapidly lowering the blast cell count by an average of 50% after one dose in each of ten episodes. No patient developed symptoms or signs of the leukostasis syndrome, and no side effects directly attributable to hydroxyurea were observed. The leukostasis syndrome associated with very high blast cell counts in adults with acute leukemia can be avoided by the use of hydroxyurea in the manner described. This treatment can be particularly useful in the interval before consultation or referral and prior to the cytotoxic effect of definitive induction chemotherapy.


Cytogenetic evidence of clonal evolution in 5q- anemia. The clinical homogeneity of myeloproliferative syndromes associated with a 5 q- marker can be contested, but nevertheless finds support in the 2 case reports we have cited. One of these observations of refractory anemia with partial myeloblastosis and 5 q- marker has shown a transformation into an acute myelomonocytic leukemia with clonal chromosomal evolution.


Initial prognostic factors and lymphoblast-erythrocyte rosette formation in 109 children with acute lymphoblastic leukemia. Bone marrow lymphoblasts from 109 children admitted with untreated acute lymphoblastic leukemia (ALL) were tested for spontaneous rosette formation with sheep erythrocytes. Twenty-six children (24%) had lymphoblasts that formed rosettes (E+). Of 13 initial clinical characteristics, 8 were significantly associated with E+ lymphoblasts: mediastinal enlargement (86% of patients E+), leukocyte counts over 100 X 10(9)/liter (65% E+), nodes greater than 2 cm in any diameter (65% E+), age over 5 yr (46% E+), hemoglobin over 8 g/dl (44% E+), hepatomegaly greater than 5 cm (38% E+), boys (35% E+), and lymph node enlargement outside of the cervical area (28% E+). Spleen size, initial platelet counts, and periodic acid-Schiff scores did not distinguish E+ from E- patients. Since few patients were black and few presented with central nervous system leukemia, the association of these two characteristics with E+ blasts could not be determined. A hierarchical classification scheme and a linear logistic regression model were used to define the patterns of characteristics associated with E+ lymphoblasts. The initial clinical characteristics and the poorer course of E+ patients suggest that ALL comprises at least two biologically and clinically distinct types. The E+ ALL may result from a leukemic transformation of a non-Hodgkin lymphoma.


Globin synthesis in mouse erythroleukemia cells in vitro: a switch in beta chains due to inducing agent. Friend erythroleukemia cells, originally derived from DBA/2 mice, differentiate when cultured with inducing agents. Studies of the different effects of inducing agents on clone 745 have revealed that both dimethyl sulfoxide (DMSO) and hemin produce benzidine-positive cells. Butyric acid produced mature but benzidine-negative cells in this clone. All agents induced globin synthesis above the 0.1% of protein synthesis found in uninduced cells. DMSO induction stimulated globin synthesis 9%, hemin 2%, and butyric acid 3%. Total beta/alpha ratios were approximately unity with all agents. Although the inducing agents all stimulated total globin synthesis in Friend cells, the relative rates of synthesis of the two mouse beta chains were affected differently by the various agents. Hemin markedly increased the proportion of beta minor. For example, DBA/2 mouse reticulocytes synthesized 20% beta minor and 80% beta major. DMSO induction of clone 745 caused 20%-33% synthesis of beta minor. In contrast, hemin increased the proportion of beta minor to 64%-69%. Thus the Friend erythroleukemia cell system provides an in vitro approach to the study of the regulation of globin-chain switching.


Bone remodeling in pathologic conditions. A scanning electron microscopic study. Bone remodeling in pathologic conditions was studied with the scanning electron microscope (SEM). Benign and malignant ossification were examined in cases of myositis ossificans, ossifying fibroma, osteoid osteoma, and osteosarcoma, Resorption of bone due to invasion by non-ossifying tumors was found in cases of squamous cell carcinoma, adenocarcinoma, ameloblastoma, and multiple myeloma. Bone formation due to excessive production of growth hormone was studied in a case of acromegaly. Resorption of bone due to pathologic processes resembled the pattern found in surfaces which were undergoing resorption by osteoclasts. Lamelar-cortical bone formation in acromegally was similar in nature to normal bone. The deformities were rleated to the excessive continuous osteogenesis that occurs in these instances. Neoplastic ossification was characterized by calcifying globules, the diameters of which ranged from 1 to 3 micron. The surfaces of these globules were constructed of minute calcospherites with diameters ranging from 0.1 to 0.3 micron. It is suggested that the pattern of globular calcification is similar to the type that was found with the SEM in fetal bone and cartilage, during healing of fractured bone, and also with the TEM in normal and pathologic calcification.


Chromosomes and causation of human cancer and leukemia. XXIII. Near-haploidy in acute leukemia. A case of acute lymphoblastic leukemia (ALL) with a near-haploid (27 chromosomes) leukemic cell population in the marrow has been described and the findings compared to those of the only other such case in the literature. In both cases the cells with 27 chromosomes, except for one chromosomal group, had karyotypic findings which were identical. Cells with 54 chromosomes, karyotypically exact duplicates of the cells with 27 chromosomes, were also encountered; on morphological basis it appeared that the marrow contained large and small lymphoblasts, possibly matching the metaphases with 54 and 27 chromosomes, respectively. The genesis of the cells with 27 chromosomes was uncertain and several postulates are discussed, as well as the relation of the findings to the cytogenetic observations encountered in ALL and their possible role in human leukemogenesis.


Chromosomes and causation of human cancer and leukemia. XXVI. Binding studies in acute lymphoblastic leukemia (ALL). Chromosomes were studied in the bone marrow cells of 101 patients with acute lymphoblastic leukemia (ALL) hospitalized at or attending the clinics of Roswell Park Memorial Institute (RPMI) between January, 1968, and December, 1976. Aneuploidy was observed in about 50% (54/101) of the cases. Two cases were hypodiploid and the remaining were either pseudo or hyperdiploid. The frequency of abnormalities and the chromosomal numbers were similar to those of 106 cases studied in our laboratory prior to 1968. Of 50 recently unselected cases of ALL in whom Q- and G-banded karyotypes were attempted, 31 were successfully analyzed with these techniques. The banding patterns revealed 16 cases to have chromosome abnormalities and four of these to have a similar abnormality, i.e., partial deletion of the long arm of chromosome no. 6: two cases had a 6q- with additional abnormalities and two had 6q- as the sole karyotypic abnormality. The breakpoint in chromosome no. 6 seemed to involve a segment from q21 to q25. An isochromosome of the long arm of no. 7, i(7q), was observed in two cases, two additional no. 21 chromosomes were observed in five cases and, except for the Y, all other chromosomes participated in the karyotypic changes encountered in the 16 cases in which banding analyses were performed. Banding analysis has afforded the first reliable approach towards ascertaining karyotypic evolution in ALL, which was achieved in eight cases of the present study. The chromosomes contributing to this karyotypic evolution were distributed widely. Thus, all chromosomes except the Y participated in numerical and/or structural karyotypic changes. Even though nonrandom chromosome changes may occur early in ALL, the pristine prototypic picture of the karyotypes in ALL is often obfuscated by successive chromosomal changes and hyperdiploidy by the time the karyotypes are analyzed in this condition. Further cytogenetic studies are required, with special attention to karyotypic evolution, in order to uncover the significance of chromosomal changes in early and late ALL.


Disseminated atypical tuberculosis-antedating the clinical onset of neoplasia. Two cases of disseminated atypical tuberculosis are presented in which the infection anteceded by over four years the development of acute granulocytic leukemia on one and Hodgkin's Disease in the other patient. The presence of disseminated atypical mycobacteriosis in the absence of a clearcut underlying illness suggests a "preneoplastic state." It should alert the clinician to the possibility of a neoplastic disorder which may not become clinically manifest for several years.


Prolonged remission of leukemia associated with polycythemia vera. A patient with polycythemia vera (PV) received successive treatment by phlebotomies, radioactive phosphorus, myleran and cyclophosphamide. Sixteen years after the diagnosis, he developed acute myeloblastic leukemia. A complete remission was achieved following two courses of COAP (cyclophosphamide, vincristine, Cytosine Arabinoside, and prednisone) therapy. Four months later, while still in leukemic remission, he became mildly polycythemic again and the treatment with phlebotomies and cyclophosphamide was resume. The patient has subsequently been in complete remission of leukemia for over three years and his polycythemia is controlled by small doses of cyclophosphamide. This appears to be a unique case of such a prolonged remission of leukemia in the course of PV, with a return to a mild polycythemia state.


Adult acute leukemia: frequency of central system involvement in long term survivors. The incidence and frequency of CNS relapses in long term surviving adults, age eighteen and over, covering the period 1967-1972, were presented. Four of 20 patients with ANLL and 12 of 24 patients with ALL were demonstrated to have CNS leukemia during the course of their illness. The onset of neurologic manifestation in three of four ANLL patients with CNS leukemia was observed within three months of the diagnosis, whereas it was delayed to 6-12 months interval in eight of 12 ALL patients. CNS relapses, a major determinant for CNS prophylactic and maintenance therapy, were observed in 75% of the patients with ALL and none in ANLL patients who were treated with I.T. chemotherapy and cranial radiation of 2000 R. Therefore, our observation suggests that CNS prophylactic and maintenance therapy should be of value in adults with ALL as in children; whereas, in ANLL, further observation is warranted before any definite therapy can be advocated.


Intraosseous well-differentiated osteosarcoma. A series of 27 patients with intramedullary osteogenic sarcomas that were so well-differentiated histologically as to be confused with benign lesions was studied. Of the 27 patients, 14 were females and 13 were males, and most were adults. The tibia and femur were involved commonly. Roentgenographically, the tumors showed a mixture of sclerosis and lysis with poor margination. However, they lacked the highly destructive appearance of high-grade osteosarcomas. Histologically, spindle cells with minimal cytologic atypia were arranged in interlacing bundles. Mitotic figures were scarce. The amount of osteoid was variable, commonly being abundant. With recurrence, three tumors became highly anaplastic. Excision of tumor almost invariably led to recurrences. Resection or amputation has led to good results in seven patients. Only three of the 27 patients died with metastatic tumor; one patient is alive with metastasis. Central low-grade osteosarcomas have been misdiagnosed frequently and hence treated inadequately. Careful roentgenographic and histologic correlation is required to make the diagnosis.


Cytosine arabinoside and 6-thioguanine in the treatment of childhood acute myeloblastic leukemia. Twenty children with acute myeloblastic leukemia were given induction and maintenance regimens combining cytosine arabinoside (ARA-C) and 6-thioguanine (TG). Two died before completing induction therapy and were considered unevaluable. Of the 18 remaining patients, 3 died shortly after induction, 2 had no response, 1 had a partial response and 12 (66%) had a complete remission (CR) lasting 4 to 68 months. Six still survive: two in their initial CR and four who relapsed but were reinduced to CR. Although no prophylactic central nervous system (CNS) therapy was given, only one patient has developed CNS involvement after diagnosis. Two girls became pregnant while on maintenance therapy. One delivered a normal, full-term infant; both she and the child are well 24 months later.


Methotrexate-induced sudden fatal pulmonary reaction. A teenage girl in bone marrow remission with acute lymphocytic leukemia died suddenly from pulmonary edema. She had taken her first oral dose of methotrexate and cyclophosphamide 10 hours previously when she was feeling well and was asymptomatic. One week previously she had received the last of four intrathecal injections of methotrexate. Autopsy showed marked pulmonary edema as well as chronic lung changes, as previously described in patients with methotrexate pneumonitis. There is usually at least a 12-day interval from the onset of administration of methotrexate to the onset of the lung toxicity. The authors suggest the patient was sensitized by the intrathecal methotrexate and then reacted with angioneurotic edema of the lung when given the first oral dose of methotrexate. Careful examination for infectious agents, including electron microscopy, was negative.


The effect of L-asparaginase of plasma coagulation factors in acute lymphoblastic leukemia. Serial coagulation studies were performed in 26 pediatric patients with acute lymphoblastic leukemia during initial induction therapy with vincristine, prednisone, and L-asparaginase. Prolongation of screening coagulation tests was frequent: prothrombin time (in 16 of 26 patients), partial thromboplastin time (23/26) and thrombin time (21/26). In all 26 patients fibrinogen levels fell below .20 g/100 ml and 16 had levels below .10 g/100 ml. Sixteen patients had plasma coagulation factor assays performed. In these 16 patients, Factor XI was less than 40% in 14 and Factor XI was less than 70% in 9, with only a few scattered low levels of other factors. There were no clinical bleeding episodes. Coagulation abnormalities returned to normal at the completion of L-asparaginase therapy while the patients remained on vincristine and prednisone.


Long-term survival in acute leukemia in Argentina: a study of 78 cases. A total of 78 patients with acute leukemia [69 acute lymphoblastic leukemia (ALL) and 9 acute myeloblastic leukemia (AML)] survived more than 4 years. In the years between 1958 and 1967 the number of patients with ALL in Argentina who survived 4 years was 1%. This increased to 21% in the years between 1967 and 1972. The major cause of this increase was the initiation in 1967 of protocols of therapy on a national scale through a cooperative group known as GATLA. In AML patients the number of long-term survivals remained unchanged during both periods. A large percent of the long-term survivors had lower WBC, a higher platelet count, and no hepato- or splenomegaly, lymphadenopathy, or hemorrhagic manifestations at diagnosis. However, only for those patients with a WBC under 100,000/mm3 at diagnosis was there a significant prognostic implication (p less than 0.01). Patients with acute lymphoblastic leukemia who survive more than 4 years without relapse have about an 80% chance of long survival. For those who have lived 4 years with one or more lapses, there is only a 17% chance of long survival, and of these only those who develop extramedullar relapse (CNS or testicular) without bone marrow involvement have a chance of long survival. Patients who live 4 years in continuous complete remission have the same chance of very long survival regardless of previous therapy.


Acute myelomomocytic leukemia terminating in histiocytic medullary reticulosis: cytochemical, cytogenetic and electron microscopic studies. A case of acute myelomonocytic leukemia terminating in histiocytic medullary reticulosis is reported. The evolution of a single cellular clone presenting with progressive change of the morphological features of the leukemic cells towards more anaplastic elements endowed with prominent phagocytic properties is suggested on the basis of both cytochemical and chromosomal data. The histiocytic nature of the malignant proliferating cells and platelet phagocytosis has been confirmed by electron microscopic investigation. The main pathogenetic explanations of the evolutionary patterns of the disease are discussed with relation to: a) involvement of a common stem cell giving rise to different proliferative patterns of cells in a multiphasic sequence; b) release of dysplastic platelets and defective erythrocytes with massive sequestration by histioid phagocytic cells; and c) coexistence of two different disorders.


Quantification by DNA-based cytophotometry of the 9q+/22q-chromosomal translocation associated with chronic myelogenous leukemia. DNA-based cytophotometry was used to analyze metaphase chromosomes in four patients with chronic myelogenous leukemia. In three of these patients, both Philadelphia chromosome (Ph1)-positive and Ph1-negative cells were measured. On the basis of these three patients, the characteristic 9q+/22q- translocation of chronic myelogenous leukemia involves the net transfer of 0.325% of the autosomal genome; there is no evidence of net gain or loss of DNA (apart from duplication of the Ph1 chromosome in one patient), and no significant difference is found in the amount of DNA transferred in different patients. Significant differences are found among patients in the derived Chromosomes 9 and the Ph1 chromosomes and are ascribed to preexisting variations in the Ph1-negative cells of these patients. There is no evidence in these patients of any further cytogenetic lesion associated with chronic myelogenous leukemia.


Characterization of a glucocorticoid-sensitive human lymphoid cell line. A human lymphoblastoid cell line (CEM), the growth of which is inhibited by glucocorticoids, is described. Although growth of the original uncloned cell line is only slightly retarded by dexamethasone, sensitive clones were isolated in which growth is completely blocked by 2 to 3 days of exposure to 10(-6) M dexamethasone. After 4 to 5 days, these cells become pyknotic and lyse. The inhibitory affect of dexamethasone first become apparent in suspension culture at a concentration of about 5 X 10(-8) M. Receptor analysis showed the presence of specific glucocorticoid receptors with an apparent dissociation constant for dexamethasone of about 1.3 X 10(-8) M both in the sensitive and in one resistant clone analyzed. Ability to displace dexamethasone from the receptor is correlated with the known glucocorticoid activity of all steroids tested, as is their ability to inhibit cloning of sensitive cells in agarose. These results indicate that the specificity of inhibitory effects is related to receptor specificity of inhibitory effects is related to receptor specificity. Dexamethasone is a potent inhibitor when cells are cloned in agarose, having a marked effect even at a concentration of 7 X 10(-9) M. CEM cells thus provide human cell lines suitable for in vitro analysis of steroid effects on leukemic cells.


Alteration of prostaglandin biosynthesis in rat chloroleukemic tumor. Data from our present studies demonstrate the capability of a 105,000 X g pellet from rat normal bone marrow, turpentine-induced hyperplastic bone marrow, and chloroma tumor to transform precursor arachidonic acid into prostaglandins. The activity of the prostaglandin synthetase systems in these tissues is inhibited by the known nonsteroid antiinflammatory drug indomethacin and by two unsaturated fatty acids previously demonstrated in other tissues. Although the overall biosynthesis of prostaglandin E2 (PGE2) was higher in the hyperplastic bone marrow than in the chloroma tumor, the PGF2alpha:PGE2 ratio was markedly higher (8-fold) in the chloroma tissue. This latter increase was probably due to the increased transformation of PGE2 into PGF2alpha by the NADPH-dependent PGE2 9-ketoreductase (an enzyme that catalyzes the transformation of PGE2 and PGF2alpha). These results indicate the greater capability of the malignant chloroma tissue to form PGF2alpha than of nonmalignant hyperplastic bone marrow. Although the role of PGF2alpha in the malignant myelogenous leukemic tumor is presently unclear, its increased formation in this tissue suggests that this substance may play a role in the hyperproliferative process.


Studies on flies in Korea I. Taxonomical studies on calliphorid flies (Diptera). A total of 97 species of flies collected in Korea since 1919 is described which consists of the collections by Kobayashi, Hori and the author. They include 19 species belonging to 12 genera of the family Calliphoridae, 38 species belonging to 15 genera of the family Sarcophagidae and 40 species belonging to 14 genera of the family Muscidae. The specimens were identified according to the male genitalia, which generally show little variations among the flies of the same species, and were illustrated. The geographical distribution and localities in Korea of all the species are presented, and the medically important species are discussed in detail. Of these flies, the calliphorid species in Korea are described and illustrated in this paper. The author found newly 8 species of calliphorid flies including a new species. As for the families Sarcophagidae and Muscidae, the descriptions on these will be published in part II and part III, respectively, in the near future.


Studies on medically important flies in Thailand. III. Report of species belonging to the genus Musca Linné, including the taxonomic key (Diptera: Muscidae). Twenty species belonging to the genus Musca Linné are reported from Thailand with taxonomic key. This study is based on the specimens available in the authors' collection and 8 species are the new records from this country. The newly recorded species are Musca interrupta pilifacies, M. lucens, M. fasciata, M. pattoni, M. planiceps, M. xanthomelas, M. bezzii and M. convexifrons.


Histotoxic properties of carbon monoxide in the living organ I. Fluorometry of oxidation-reduction state of the rabbit kidney in situ. Effect of carbon monoxide on the redox state and blood flow in the renal cortex of the rabbit was examined by the fluorometric method. By a short-period (1-3 min) inhalation of CO in concentrations over 1%, the following were revealed: (1) Reduced pyridine nucleotide was increased, (2) oscillatory change of the reduced pyridine nucleotide, which is characteristic for the histotoxic reaction, developed, and (3) extent of the fluorescence changes tended to be in proportion to the concentration of CO, but no change was caused by inhalation of CO in lower concentrations (0.1%, 0.5%) even if the inhalation was continued for 30 min. As to the blood flow, CO in concentrations over 0.5% decreased it, whereas anoxia due to nitrogen increased it. Some implications were discussed from toxicological points of view on the results obtained.


Biocompatibility of polysulfone composite materials for dental implant. As a part of the work designed to find a material suitable for a dental implant, tissue reaction of various kinds of polysulfone composite materials has first been studied by implantation in the femur of rats and in the mandible of rabbits. Histological examination showed that the porous polysulfone composite containing 20 wt.% of tricalcium phosphate exhibited a favorable osteogenesis. The tooth replica implants made of this composite material were inserted into the extraction sockets of dogs. During 5.5 months of observation, horizontal or diagonal orientation of periodontal fibers, no epithelization, and no alveolar bone resorption were noted. This study suggests a promising feasibility of the polysulfone-calcium phosphate composite material as a dental implant material.


Immunological characteristics of lymphoblasts and lymphocytes in acute lymphoblastic leukaemia in children. By analysing the electrophoretic mobility (EM) of lymphocytes and by comparing their surface charge it is possible to distinguish rapid-moving lymphocytes (T) and slow-moving lymphocytes (B). The authors studied the EM of blood lymphocytes in children suffering from acute lymphoblastic leukaemia, before they underwent treatment. At the same time they carried out a study of classical immunological markers (E rosettes, membrane immunoglobulins, and blastic-transformation ability). The authors were able to distinguish three types of lymphocytes according to their EM i.e., rapid, slow or intermediate. This heterogeneousness could be explained by the fact that the origin of leukaemic proliferation may vary according to different stages in the maturation of the lymphoid cells. It would seem premature to establish any correlation between the initial clinical signs of the disease and its evolution.


[The social hygieneic importance of the cooperation of internal medicine and stomatology]. The contents of this paper are divided into three parts: the first points to the health risk for the dentist and his patients which has only been recently recognised to its full extent and seriousness: the transmission of virus hepatitis during dental treatment. The second section tries to enrol the help of oral surgery to detect the large number of unrecognised cases of hypertension through the introduction of blood pressure measurement into dental practice. The subject of the third section is the problem patients and patient problems deriving from medical diseases which crop up almost daily in dental practice and which should lead to interdisciplinary consultation between oral surgery and internal medicine.


[Gynecological and obstetric problems in connection with stomatology]. Hormonal changes during pregnancy produce changes in the whole organism. Every fifth to seventh pregnant woman shows hyperplastic gum changes with tendency to bleeding. Changes due to pregnancy in the oral cavity are: lowered salivary flow rate, changes of the pH towards acidity and an increase in oestrogen contents of saliva, corresponding to the increase in plasma oestrogen. Dental procedures during the first months of pregnancy could be the cause of miscarriage in rare cases; after the 28th to the 30th week of pregnancy external influences can originate premature labour pains. Endocrinological changes during the menstrual cycle give risk to recognisable cycle-dependent changes in the oral mucosa; changes in the blood clotting mechanism are minimal, so that dental interventions can be practiced independent of the menstrual cycle and the occurrence of the menstrual period. The use of oral contraceptives (pills) leads to hypercoagulability of the blood clotting system. For bigger operative interventions it is advisable to normalise the clotting factors by stopping the pill for six weeks prior to planned intervention.


[Forensic dentistry as an important part of legal medicine]. Forensic dentistry is divided into two main subjects: 1. Dental jurisprudence and ethics and 2. Dental criminology. Dental jurisprudence and ethics include the legal duties of the dentist. They concern foremost the contractual relations between him and the patient and the duties which result from his actual dental activities, especially concerning his therapeutic measures. In major disasters successful identification is possible if a careful register is taken of dental states by all dentists.


[The role of the dental officer in catastrophic situations with large numbers of casualties]. During and after military operations, the dental officer helps the medical officer with his knowledge and experience in treating maxillo-facial injuries. According to experience of past wars, head injuries are likely to amount to 10% of all casualties. If the number of casualties is very high, the dental officer will give all general medical assistance which he is qualified to give by his training. To enable him to fulfill all his tasks, the armed forces will give him special training in catastrophe medicine.


[Surgical correction of deep bite for the prevention of periodontal damage]. The operative corrections used up to now which were limited to the displacement of the maxillary frontal fragments of the alveolar process, only bring about a partial correction of the deep bite. For this reason additional operative methods on the mandible are recommended, which vary according to the bite. When the bite is neutral the fragment of the lower alveolar process should be placed deeper and should be tilted forward. On the other hand in distal bite cases the recommended procedure is, after dealing with the upper front according to maxillo-facial principles, to correct the mandibular retrusion and deep bite by deepening and advancing the lower alveolar process.


[Peripac and Histoacryl as bandaging materials after removal of dental calculus and subgingival curettage]. Scaling and subgingival curettage were performed on the upper and lower front teeth of 25 patients in the age of 25 to 35 years. Peripac was applied to the periodontal tissue of three of the six teeth treated per subject and Histoacryl to the periodontal tissue of the other three teeth. Prior to and three months after the beginning of therapy, pocket depth, sulcus bleeding tooth mobility were determined. It was found that the use of Histoacryl as a dressing material is not a disadvantage as compared to the conventional dressing Peripac as far as therapeutic success in terms of declining pocket depth and SBI is concerned.


[The determination of mechanical properties of hard tissue surfaces in microareas by means of mechano-electrical methods]. The resistance of surfaces of hard tissue against chemical attacks e.g. acids can be measured with high spacial specifity by electro-mechanical registration of surface topograms. Apart from this property of hard substance, important in connection with the development of caries, the sample principle of measurement can be used in vitro on dental surfaces to obtain other important measurements. Examples are given to show how the hardness is determined by the summation of elastic and plastic properties. It is shown how far during the usual measurements for hardness of impressions the duration of the process and the time elapsed before measurement can influence the results.


[Temporomandibular joint involvement in chronic polyarthritis]. As a systemic mesenchymal disease, chronic polyarthritis may affect all joints of the human body. A review of the literature revealed that opinion varied considerably with regard to the involvement of the temporomandibular joint. We made detailed studies in a restricted number of cases using an already existing computerized form.


[The dissociated hypersthesia in Vincent's symptom--an indication of the etiology]. The so-called Vincent's symptom is a functional disturbance in the region of the distribution of n. alveolaris mand. Etiologically, it may be due to pathologic disorders of different origin. In fractures of the mandible with rupture of the nerve in the mandibular canal, complete anesthesia is observed. In inflammatory processes pain is first felt differently, later anesthesia is noted. In the case of a space-occupying lesion, tactile differentiation is disturbed first and pain sensation only after a relatively long time. In the case of infiltrating tumors, a neuritis is noted first (late Vincent's symptom). Thus, partially disturbed sensitivity may be a helpful symptom for differential diagnostic considerations, as is demonstrated in a number of cases.


[Animal model for the etiopathogenesis of sialadenitis]. A longitudinal study with patient-specific jaw models and simultaneous X-Rays was undertaken to examine the eruption behaviour of the mandibular premolars following physiological and pathological resorption of the roots of primary teeth. 1. The molars of the first dentition fall out earlier after pathological resorption of the roots of primary teeth. In the presence of an occlusal bony bridge the appearance of a new tooth may take years. The eruption of the replacing tooth is delayed or it may be retained. 2. The eruption times of premolars after physiological resorption of primary tooth roots given in the literature and those obtained by the author converge. After pathological resorption of primary tooth roots and rarefying osteitis with interruption of the lamina dura, vertical development occurs significantly sooner (p less than 0,01). 3. The sequence of eruption of the premolars can be altered after pathological resorption of primary tooth roots.


[Synthesis of extracellular polysaccharides by various forms of Streptococcus salivarius]. Streptococcus salivarius synthesizes extracellular polysaccharides (EPS) from saccharose under aerobic and anaerobic conditions. Under aerobic conditions primarily soluble fructanes are formed. There are no differences between the EPS synthesized by r- and s-forms under aerobic conditions; anaerobically the s-forms produce more EPS and more fructane than the r-forms. As compared to streptococcus mutans, the streptococcus salivarius produces considerably more fructane and insoluble glucane under the conditions used.


[Cariogenic properties of various snacks in animal experiments]. In a conventional animal experiment with rats, the cariogenic properties of different snacks were studied and compared. Bananas caused the highest caries incidence, apples the lowest. In between ranged the caries values of two other tested sweets, wafers and gum drops. The differences in caries incidence were due to specific chemo-physical properties (stickiness, fat content). In addition to the evaluation of caries incidence, microbiological plaque examinations and sugar analyses of the tested substances were carried out.


[The metabolic behavior of the human plaque flora towards the sugar substitute xylitol]. By means of the Warburg technique, whether and to what extent microorganisms of the human plaque can metabolize xylitol under both aerobic and anaerobic conditions was studied, and the results were compared with those for saccharose. Under the chosen test conditions, this sugar alcohol was metabolized, if at all, in negligibly small traces only, during eight hours.


[Epidemiological results of the study on tooth destruction carried out at the Marburg dental clinic]. The individual components of the DMF-T-index checked for age and sex were examined in 2655 patients, who first attended the ZMK clinic in Marburg in 1974, as regards their connection with social and geographical origins. Results of a comparative study, which is restricted to dental findings of patients between the ages of 15 and 64 from the town Marburg and the country area Marburg-Biedenkopf are presented. The wisdom teeth are not included.


[Available fluoride from various drugs after oral application]. Fluoride profiles (period of estimation 24 hours) after oral intake of 6 different preparations were made in human plasma and parotid saliva. It was shown that the fluoride concentration was highest when NaF was administered. Concentration returned to normal after about 8 hours. The values in parotid saliva were slightly lower than in plasma. Both profiles ran approximately parallel. A pre-eruptive, caries-prophylactic action can here be expected where bio-availability is especially favourable.


[The effect of chlorhexidine gluconate on plaque and gingivitis]. In a clinical study, the influence of chlorhexidine digluconate (0.1%) on the incidence of dental plaque and gingivitis was examined in subjects with insufficient personal oral hygiene. Statistical evaluation showed that compared to a placebo, chlorhexidine digluconate had a significant plaque inhibiting effect. The gingivo-therapeutic effect of this substance was statistically significant.


[Antimicrobial properties of cements with and without copper content]. Copper-containing cements seem to inhibit bacterial growth better than copper-free materials. Twenty-four hours after insertion, a statistically significant difference is noted. The initial bactericidal effect of copper-free cements declines considerably as compared to copper-containing cements. The results obtained largely correspond to those given in the literature. The method used of including bacterial suspension in a liquid medium is suitable to establish dose-reaction curves for dental materials.


A case of Gilles de la Tourette's syndrome accompanied with alcoholism. A case of Gilles de la Tourette's syndrome with alcoholism and migraine is described. Multiple motor tics and coprolalia were suppressed by the treatment with haloperidol. The concentration of HVA and 5-HIAA in the cerebrospinal fluid were measured and increment of HVA concentrations was outstanding while his symptoms were aggravated. This might be evidence for hyperactivity of dopaminergic neurons involved in manifest symptomatology of this syndrome.


[Extracoporeal irradiation of blood in the treatment of leukemia. Experiences on 25 patients with chronic lymphadenosis]. Extracorporeal irradiation of the blood (ECIB) is a valuable addition to the treatment of chronic lymphatic leukemia (CLL). Possibly the prognosis of chronic lymphatic leukemia can be significantly influenced by early treatment. In acute leukemia the increase of bone marrow proliferation can be useful in cases resistent to chemotherapy. Side effects of ECIB have not been observed.


Studies of bone and soft-tissue tumours induced in rats with radioactive cerium chloride. A colloidal suspension of radioactive cerium chloride was inoculated into the hind legs of Sprague Dawley rats. Bone and soft-tissue tumours were induced at the site of inoculation in 77% of the animals. All bone tumours were osteogenic osteosarcomas. Soft tissue tumours were mostly malignant and were of various histological types, predominantly fibrosarcomas, haemangiopericytomas, angiosarcomas and rhabdomyosarcomas. A kinetic study showed that the doubling time (DT) of tumours was closely correlated with the anatomical site of tumour development: bone tumours had a DT of 17.4 +/- 4.3 days and malignant tumours which developed in soft tissues had a DT ranging from 7.4 to 8.4 days with the exception of two haemangiosarcomas which had a long DT of 17 +/- 0.6 days. Pulmonary metastases were frequent for osteosarcomas and tumours of vascular origin. This model of induction of bone and soft-tissue tumours in rats by injection of a colloidal suspension of radioactive cerium chloride offers the possibility of more comprehensive physiopathological and kinetic studies of these tumours and may constitute a good model for their human counterparts.


[Cellular relations during odontogenesis]. Epithelial-mesenchyme interactions during mouse molar tooth morphogenesis were observed by electron microscopy. The basal lamina was intact from day 10 to day 18. Aperiodic, later also periodic fibrils were deposited on the basal lamina. Ectomesenchymal cell processes were always in close relation with the basal lamina or with the fibrillar material. On day 19 some direct heterotypic cell contacts between odontoblasts and preameloblasts were observed. At all stages, especially the preodontoblasts but also preameloblasts, gave rise to aggregated vesicles, which were extruded in the epithelial-mesenchymal space.


[Ultrastructural study of the cellular cementum in rats]. The study of the cementum of adult rat molars has essentially shown resting and developing surfaces. The resting cementum surface is covered by fibroblasts oriented perpendicular to the surface and surrounded by collagen bundles entering perpendicularly in the cementum or oriented parallel to the surface. On the surfaces with apposition, cementoblats and cementoid cementoblasts, becoming finally cementocytes, were observed. A decrease in cytoplasmic organelles is noted in these latter cells when going from the surface to the cementum depth. An organic pericementocytic space is located between the comentocyte cytoplasmic membrane and the lacunar calcified wall. In the interlacunar tubules, tight and gap junctions were present between the cytoplasmic processes of adjacent cells. Groupings of several epithelial-like cells were embedded in large intracemental cavities. They probably correspond to epithelial rests of Malassez.


[Experimental allergic pulpitis in rabbits]. Ten male, albino rabbits, weighing about 2,5 kg, were sensitized with 0.05% of 1-chloro-2,4-dinitrobenzene (DNCB) in complete Freund's adjuvant. Ten controls received the complete Freund's adjuvant only. Fourteen days later, the animals were submitted to a dental test. The four incisor pulps were exposed under general anesthesia. A sterile cotton pellet with 10-(-4) mg of DNCB was sealed inside the cavity. A skin test was also performed with 0.1% DNCB. The operative trauma was evaluated on five additional control animals. Twenty four hours after the challenge, the animals were killed and their teeth were studied histologically. Three different pulpitis were observed: 1) in animals without DNCB, a traumatic pulpitis with a mild focal necrosis and serous infiltrate; 2) a toxic pulpitis induced by the DNCB in the controls. They were killed and their teeth were studied histologically. Three different kinds of pulpitis induced in sensitized animals. A considerable necrosis is present close to the pulp exposure. This pulpitis is characterized by a marked serous exudate and by an accumulation of lymphocytes, eosinophils and macrophages, either perivascularly or in the pulpal mesenchyme. A modification of the present classification of pulpitis is proposed.


Human submandibular gland tissue in culture I. Sulphate incorporation and tissue culture technique. In vitro cultivation of human submandibular gland tissue resulted in release of salivary proteins corresponding to about 50% of the total content after 48 hours. The admixture of plasma proteins as judged by single radial immunodiffusion took place early in the incubation period, and could be reduced by discarding the first washing medium. Hydroxyproline measurements in the medium indicated that the autolysis increased significantly after two days of incubation. Isoelectric focusing of human submandibular proteins resulted in fractions with isoelectric points closely resembling those demonstraded earlier for monkey submandibular gland proteins, but with larger acid fractions and smaller basic fractions. Virus haemagglutination inhibition (HAI) activity and sulphate incorporation was demonstrated in the most acidic, viscous fractions, whereas L-leucine incorporation was found in all fractions of the isoelectric scale. No sulphate affinity to submandibular proteins, independant of the in vitro protein synthesis, could be detected by equilibrium dialysis or other control measures.


Human submandibular gland tissue in culture 2. Nickel affinity to secretory proteins. In view of the exposure to nickel through the oral cavity the relation between this metal (as 63NiCl2) and salivary macromolecules was studied by tissue culture, isoelectric focusing and equilibrium dialysis. During cultivation of human submandibular gland tissue, small amounts of nickel were incorporated into macromolecules with an isoelectric point of about 4.4 and approximately 7.5. No affinity independent of the protein synthesis was revealed between nickel and submandibular proteins, including the acidic, viscous, sulphate-incorporating glycoproteins. It is therefore possible that a nickel-containing metalloprotein is present in the submandibular secretion, but a complex formation between nickel and macromolecules similar to the nickel-albumin transport system in plasma was not found. The affinity of nickel to small molecular substances in the secretion was not studied.


Synthesis of bacteriocins in liquid cultures of Streptococcus mutans. Strains of Streptococcus mutans synthesized bacteriocins in agar plates, but synthesis of detectable bacteriocins in liquid media took place only under certain culture conditions. The composition of the medium proved to be crucial. Trypticase Soy Broth with 4% Yeast Extract meeting the requirements. The effect of the Yeast Extract is obscure, for some strains also formed detectable bacteriocins in a special Trypticase medium without this agent. It was noted that the broth should be filter-sterilized rather than autoclaved and only a few days old. Attempts at liberating cell-bound bacteriocins from washed cells were unsuccessful, even when they were treated with ultrasound, EDTA, or various chemicals followed by ultrasound. On the basis of size and sensitivity to heat the bacteriocins could be divided into two groups, while their resistance to ether and chloroform and to trypsin did not follow this pattern. Dependence on plasmids could not be demonstrated by attempts at curing with acridine orange or ethidium bromide; and the involvement of phages was unlikely, since the inhibition was not transmissible and phage-like structures were not observed in the electron microscope.


The pathology of renal ischaemia.

The pathology of renal ischaemia. Examination of ischaemic kidneys reveals changes which generally correlate well with the pathophysiology of renal ischaemia. Although there is an association between renal ischaemia, juxtaglomerular granulation and hypertension, notable exceptions are seen from time to time. Improved methods of identification of the contents of juxtaglomerular granules may provide better methods of prediction of those patients likely to benefit from nephrectomy for hypertension associated with renal ischaemia. Further studies of the function of mesangial cells and of the smooth muscle cells of the juxtaglomerular apparatus promises to provide information to explain the collapse of glomerular tufts, and hence of impaired glomerular filtration, following ischaemia.


Hypoxia in the newborn infant.

Hypoxia in the newborn infant. Hypoxia in newborn infants is becoming much easier to prevent, detect and treat. Nevertheless the successful management of potentially hypoxic fetuses and newborn infants remains the major challenge to all physicians concerned with perinatal care. What is at stake is not only that sick infants should survive, but equally or more importantly that the survivors should be normal children. Recent follow-up studies show that this aim can, with few exceptions, now be achieved (Stewart and Reynolds, 1974; Davies and Stewart, 1975; Durbin et al, 1976).


Ischaemia of peripheral nerve and muscle. Although skeletal muscle and peripheral nerves are both resistant to ischaemia there are nevertheless many syndromes in which they are affected, either separately or together. It is frequently difficult to distinguish the effects of arterial ischaemia from those of compression, which may operate through vascular occlusion, or, in the case of peripheral nerve, by mechanical deformation of nerve fibres. A great deal has been learned from experimental models, but not all of it is applicable to the complexity of human neuromuscular ischaemia which requires further study.


Enamel fluoride uptake and retention from intensive APF gel applications in vivo. Children, in the fifth school grade (mean age 11 years) in a fluoridated water area, self-applied acidulated phosphate-F gel (1.2% F) in custom-fitted mouthpieces on 5, 10, or 25 consecutive school days. Enamel F uptake, penetration, and retention were determined from analysis of 1,257 deciduous teeth exfoliated during and after the applications. F penetrated to 200 micrometer in enamel exposed to 25 applications of the gel and increased approximately 2,600 ppm at a 5 micrometer depth. Concentrations of F declined for approximately eight months after which levels stabilized, resulting in a 1,600 ppm increase of firmly bound F.