Involvement of IS1 in the dissociation of the r-determinant and RTF components of the plasmid R100.1. The formation of the r-determinant pLC1 and of the RTF pAR132 from the composite plasmid R100.1 was investigated. The general location of IS1 sequences on the three plasmids was established by hybridization of lambdar14 CII::IS1 DNA to EcoRI generated fragments of the various plasmids separated by agarose gel electrophoresis and transferred directly to nitrocellulose filters. The position of IS1 sequences on these fragments and the homologies between fragments were analyzed by electron microscopy of heteroduplex molecules. The results show that the excision of both pLC1 and pAR132 occurred by an exchange between the two IS1 sequences present on R100.1.


Further evidence that the ribosomal 30S proteins S3, S5, S9, S11, S12, and S18 possess specific 16S RNA binding sites. E. Coli ribosomal 16S RNA prepared by an acetic acid-urea extraction technique individually binds, in addition to the seven established proteins, 6 new 30S ribosomal proteins (S3, S5, S9, S12, S18 and S11) (Hochkeppel et al., 1976). In this communication we demonstrate the site specificity of these proteins. Binding curves of the individual proteins with acetic acid-urea 16S RNA show that the binding of all six proteins to the RNA reaches a plateau at 0.3-0.97 copies per 16S RNA molecule. No significant binding of these proteins to classicial phenol extracted 16S RNA is observed, with the exception of S13 which binds 0.2 copies of protein per molecule of 16S RNA. Specificity of binding of these proteins is also demonstrated in "chase" experiments. The site specificity of individual [3H]-labeled 30S proteins bounds to 16S RNA is tested by the addition of non-radioactive 30S total protein to the reaction mixture.


Linkage of 5S RNA and 16S+23S RNA genes on the E. coli chromosome. Episomes carrying limited regions of the chromosome where 5S RNA genes have previously been located are described. The DNA purified from each of these episomes contains one gene per molecule for each of the three ribosomal RNA species as shown by hybridization experiments.


The firA gene, a locus involved in the expression of rifampicin resistance in Escherichia coli. I. Characterisation of lambdafirA transducing phages constructed in vitro. The firA200 mutation of E. coli not only renders RNA synthesis thermosensitive but also eliminates the high-level resistance to rifampicin associated with certain mutations in the beta subunit of the RNA polymerase. A priori, the firA gene is likely to code for an essential component of the transcription apparatus. The isolation is reported of transducing phages for the firA gene, constructed in vitro by fusing fragments of the E. coli chromosomes into a lambdoid bacteriophage. Such phages carry at least two essential genes and are able to suppress both the thermosensitivity and abnormal rifampicin sensitivity associated with the firA200 allele. The finding that some, but not all, of the lambdafirA phages have a temperature dependent growth defect is discussed.


Ribosomal abnormality in recA mutants of Escherichia coli. The tif-1 mutation has been shown to affect protein synthesis in vitro by increasing translational ambiguity (Ephrati-Elizur, Luther-Davies and Hayes, 1976). It is demonstrated here that some recA mutations confer similar abnormality. By comparing suitable combinations of ribosomes and soluble proteins from recA+ and recA cells the defect is shown to be associated with ribosomes. The recA mutation, which suppresses most phenotype characteristics of the tif-1 mutation (Castellazzi, George and Buttin, 1972(b)) does not suppress the ribosomal abnormality. Since the closely linked tif-1 and recA mutations lead to the expression of a common property they may be in the same gene.


Escherichia coli plasmid pBR313 insertion into plant protoplasts and into their nuclei. Cowpea mesophyll protoplasts were shown to bind irreversibly up to 3% input radioactive pBR313 plasmid DNA after 15 min of contact. Maximum uptake occurred in the presence of 5 mM ZnSO4 and 5 microgram/ml poly-L-ornithine. Under these conditions about one half of the TCA precipitable radioactivity was associated with the nuclear fraction and behaved as linear plasmid molecules. These could not be chased from the protoplasts upon further incubation with unlabeled plasmid DNA. The presence of donor DNA within the nuclear fraction is most probably not due to an artifactual redistribution of adsorbed plasmid DNA. Prolonged incubation periods resulted in extensive degradation of plasmid in the incubation medium but little degradation occurred in the protoplasts. The donor DNA was not covalently associated with the protoplast nuclear DNA.


The regulation of RNA synthesis in yeast. I: Starvation experiments. The synthesis of tRNA in yeast is shown to be under separate control to that of rRNA during amino acid and nitrogen starvation. Inhibitors of the elongation and termination steps of protein synthesis were found to stimulate the synthesis of tRNA in starved yeast cells. This effect appeared to be due to the "trickle-charging" of tRNA. Two inhibitors of early steps in the initiation of protein synthesis were found to be unable to stimulate RNA synthesis in starved cells. It is proposed that yeast tRNA synthesis is under autoregulatory control and that the level of tRNA charging and the mRNA-ribosome complex are important components of this control system.


Genetics of ribosomal protein methylation in Escherichia coli. I. A mutant deficient in methylation of protein L11. Several thousand mutagenized clones of Escherichia coli were screened for methyl group incorporation into protein in crude extracts, in order to isolate mutants lacking the full complement of methyl groups in ribosomal proteins. One mutant isolated by this method and designated prm-1 incorporated 6-7 methyl groups per ribosome upon incubation of its ribosomes with a partially purified enzyme preparation from E. coli wild-type. The methyl groups were located exclusively in the 50S particle and for the most part (85%) in protein L11. Three methylated amino acids were detected: epsilon-N-trimethyllysine, epsilon-N-monomethyllysine, and an uncharacterized amino acid. These accounted respectively for 4.6, 1.3 and 0.9 methyl groups per ribosome. These results indicate that protein L11 in wild-type contains a stoichiometric amount of these methylated amino acids which are absent in mutant prm-1. Since this mutant is fully viable, its methylation deficiency does not result in a major defect in ribosome assembly or functioning.


Genetics of ribosomal protein methylation in Escherichia coli. II. A mutant lacking a new type of methylated amino acid, N5-methylglutamine, in protein L3. The ribosomes of an Escherichia coli mutant, designated prm-2, can be methylated in vitro by an enzymatic fraction from wild-type. This enzyme is inactive on the ribosomes from another mutant, prm-1, is reported previously to be methyl group-deficient in protein L11. In vitro methylation of prm-2 ribosomes resulted in the incorporation of about one methyl group per molecule of protein L3. After acid hydrolysis, all the methyl groups were found in a very basic compound which was identified as methylamine. This compound could have been generated by acid hydrolysis of N-methylated amide-groups from glutamine or asparagine. Therefore, chemically-synthesized N4-methyl-asparagine and N5-methylglutamine were chromatographed together with an enzymatic hydrolysate of methylated prm-2 proteins. In all the chromatogrphic systems studied the methylated amino acid was found in the same position as N5'-methylglutamine. These results indicate that mutant prm-2 lacks one residue of N5-methylglutamine present in ribosomal protein L3 of wild type E. coli.


Arsenate-resistant alkaline phosphatase-constitutive mutants of Escherichia coli. When arsenate-resistant mutants are selected approximately 50 per cent of them are also consitutive for the synthesis of alkaline phosphatase and the Pi-binding protein. Some of these mutants are linked to ilv (phoS- or phoT-), other are linked to proC (phoR-). One of the mutant strains linked to ilv lost the Pi-binding protein (the phoS gene product). Resistance to arsenate, constitutivty for alkaline phosphatase synthesis and loss of the Pi-binding protein occurred pleiotropically by the same phoS- mutation.


Genetic studies of the pyrimidine permeases from Saccharomyces cerevisiae: lack of intragenic complementation. A search for intragenic complementation of mutants of the cytosine and uracil permeases of Saccharomyces cerevisiae was made. Among numerous diploid pairs of mutants of the cytosine permease gene no complementation was found. Similarly negative results were obtained with pairs of mutants of the uracil permease. The significance of these results is discussed.


Transposition of TnA does not generate deletions. We have examined the incidence of loss of the TnA unit, Tn801, from RP1 under conditions where transposition of Tn801 to another replicon. R388, was readily detected. We found that the frequency of transposition of Tn801 from RP1 to R388 exceeded, by at least a factor of one hundred, the frequency at which it was deleted from RP1. We conclude that, in general, transposition of Tn801 does not generate derivatives of the donor plasmid which specifically lack Tn801. The relevance of these findings to the mechanism of transposition is discussed.


[Hereditary fructose intolerance (author's transl)]. Hereditary fructose intolerance (HFI) is the most important disturbance in human fructose metabolism. This paper deals with the present knowledge of biochemistry and pathophysiology of this inborn error of metabolism, which is often wrongly diagnosed and gives a detailed description of diagnostic and therapeutic procedures.


[On the diaagnosis of anorexia nervosa in children and adolescents (author's transl)]. The clinical picture of anorexia nervosa is going along with typical statements, specific pathological attitudes and psychodynamic backgrounds of the families involved. This facilities the establishment of the diagnosis already during the first anamnestic interview with parents and patients. Important are: onset of illness, eating behaviour, early childhood development, parents, brothers and sisters, leisure time, mood and personality, sexuality. In most of the cases a speedy hospital admission is necessary, because at this time the onset of the disease lies back months or even years. These circumstances redner the psychotherapy of patients and their families more difficult, and the often life-threatening attitudes of the patients more entrenched.


Induction of mutations in bacteriophage T7 by gamma-rays: independence of host-repair mechanisms. Amber mutants of bacteriophage T7 are reverted by gamma-rays to pseudo wild-type particles, i.e. particles able to propagate in a suppressorless host. The yield of revertants is much higher when the phage is irradiated in the presence of oxygen than when irradiated anoxically. Under particular gas conditions the efficiency of mutation induction differs by less than a factor of ten among six different amber codons in cistrons 1, 5, 6, 12, 17 and 19. The induction of mutations is not dependent on error-prone repair involving the recA or lexA genes of the host cell. It is estimated that of the damages that may be inflicted by gamma-rays upon an amber codon, fewer than 1 out of 85 results in reversion of the codon to pseudo wild-type.


Induction of pure and sectored mutant clones in excision-proficient and deficient strains of yeast. We have found that UV-induced mutation frequency in a forward non-selective assay system (scoring white adex ade2 double auxotroph mutants among the red pigmented ade2 clones) increases linearly with dose up to a maximum frequency of about 3 X 10(-3) mutants per survivor and then declines in both RAD wild-type and rad2 excision deficient strains of Saccharomyces cerevisiae. Mutation frequencies of the RAD and the rad2 strains plotted against survival are nearly identical over the entire survival range. On this basis we conclude that unexcised pyrimidine dimers are the predominant type of pre-mutational lesions in both strains. In the RAD wild-type strain pure mutant clones outnumber sectors in a 10:1 ratio at all doses used; in rad2 this ratio varies from 1:1 at low doses up to 10:1 at high doses. As others have concluded for wild-type strains we find also in the rad2 strain that pure clone formation cannot be accounted for quantitatively by lethal sectoring events alone. We conclude that heteroduplex repair is a crucial step in pure mutant clone formation and we examine the plausibility of certain macromolecular mechanisms according to which heteroduplex repair may be coupled with replication, repair and sister strand exchange in yeast mutagenesis.


The DNA content of micronuclei induced in mouse bone marrow by gamma-irradiation: evidence that micronuclei arise from acentric chromosomal fragments. The DNA contents of 75 micronuclei found in mouse bone marrow 48 h after a 260 R dose of gamma-rays were measured individually and compared to 71 diploid G1 nuclei. The coefficient of variation for the diploid cells was 6.3%. The DNA content of micronuclei varied from 0.5 to 11.1% of the diploid G1 nuclei with a mean of 3.5%. These results are in agreement with the expectations based upon the hypothesis that micronuclei arise from acentric chromosomal fragments produced by random breakage of the mouse genome.


Testing of some azo dyes and their reduction products for mutagenicity using Salmonella typhimurium TA 1538. A series of ten azo dyes as well as various single ring aromatic amines substituted on the benzene ring were tested for bacterial mutagenicity with Salmonella typhimurium TA 1538 using a soft-agar overlay method. Two dyes, sudan 2 and chrysoidin induced mutation but only in the presence of a rat liver preparation. Chrysoidin was the more active. Testing of its reduction products, aniline and 1,2,4-triaminobenzene showed a liver metabolite of the latter compound could be responsible for the mutagenic effect, having a comparable mutagenicity with 1,2-diamino-4-nitro-benzene, one of the mutagenic constituents of hair dyes. Structure-activity studies on a series of ring-substituted anilines indicated that mutagenic activity required at least two positions to be substituted with either amino or nitro groups, or one of each. The bacteria as well as the liver enzyme preparation may partake in the activation of these chemicals. The correlation between mutagenicity and carcinogenicity for this group of compounds is discussed.


Conditional lethal mutants of bacteriophage T4 unable to grow on a streptomycin resistant mutant of Escherichia coli. Sixteen conditional lethal mutants of bacteriophage T4D have been isolated which grow on Escherichia coli CR63 (a su+ streptomycin-sensitive K12 strain) but are restricted by CR/s (a streptomycin-resistant derivative of CR63). These mutants have been given the prefix str. Four of these mutants are amber and 12 appear to be missense. Eleven of the 12 missense mutants appear to be "pseudo-amber" (i.e. they are restricted by a su- E. coli B strain but not by a su- K12 strain); the other missense mutant was not restricted by either B or K12. The str mutations mapped in 12 different genes. Most were clustered in a region of early genes (gene 56 to gene 47). Fifty-eight amber and 10 "pseudo-amber" mutants isolated previously for their inability to grow on E. coli B were tested for restriction by CR/s. All the amber mutants grew normally on CR/s, whereas all 10 "pseudo-amber" mutants were restricted by CR/s. This implies that the phenotype of the "pseudo-amber" mutants is the result of a ribosomal difference between the permissive host CR63 and the restrictive hosts B and CR/s. These str mutants should prove to be useful alternatives to amber mutants for genetic and biochemical studies of bacteriophage T4 and for studies of the E. coli ribosome. It should be possible ot isolate similar mutants in other bacteriophages provided that streptomycin resistant hosts are available.


A study of the photoinduced mutagenicity of methylene blue. Illumination of Salmonella typhimurium strains in the presence of methylene blue resulted in the production of mutations of the base-substitution type. This photodynamic effect mediated by the dye was separable from the genetic event seen when bacteria are illuminated in the absence of added photosensitizers.


Mutagenic action of hydrostatic pressure on yeast: a cell cycle analysis. Pressure-treated log growth cultures (14,000 psi equivalent to 966 x 10(5) N/m2 for 4 h) of Saccharomyces cerevisiae were fractionated across a linear Ficoll gradient by zonal rotor centrifugation. This procedure separated the yeast cells on the basis of size and volume into a continuum of cell cycle ages. Cell survival and petite mutation frequency were determined for several zonal fractions. Survival of yeast cells after pressure treatment was maximal in zonal fractions obtained from either the top (single cells in G1) or the botton ("doublets") of the gradient. Intermediate zonal fractions showed more lethality, with minimal survival occurring in zonal fractions containing a large proportion of yeast cells in which buds were just beginning to emerge (initiation of S phase). The petite mutation frequency was minimal in zonal fractions from the top (single cells in G1) and bottom ("doublets") of the gradient. Induction increased to a maximum in those fractions containing cells in S phase.


Dynamics of x-ray-induced reversion in heterogeneous S. cerevisiae populations. The survival and frequency of adenine and homoserine revertants after X-irradiation have been studied in starved and growing populations of haploid S. cerevisiae (strain 5483/1b). A growing population is heterogeneous to cell killing, and a mathematical model can be used to determine possible correlation between sensitivity to killing and sensitivity to mutation induction. The results indicate correlation between sensitivity to ade2-1 reversion and sensitivity to cell killing, whereas no such correlation was found between sensitivity to hom3-10 reversion and sensitivity to killing. The difference in the dynamics of homoserine and adenine reversions was reduced by adding caffeine to the post-irradiation media.


Treatment of chronic stable angina. A preliminary report of survival data of the randomized Veterans Administration cooperative study. We evaluated the effect of saphenous-vein-bypass grafting on survival in patients with chronic stable angina by comparing medical and surgical treatment in a large-scale, prospective randomized study. Excluding patients with left-main-coronary-artery disease who have already been reported, a total of 596 patients were entered into this study; when randomized into a medical group (310 patients) and a surgical group (286 patients), entry clinical and angiographic base lines were comparable. Operative mortality at 30 days was 5.6 per cent. At an average of one year after operation, 69 per cent of all grafts were patent, and 88 per cent of the surgical patients had atleast one patent graft. There was no statistically significant difference in survival, at a minimal follow-up interval of 21 months, between patients treated medically and those treated with saphenous-vein-bypass grafting. At 36 months, 87 per cent of the medical group and 88 per cent of the surgical group were alive.


Autoimmune vitiligo: detection of antibodies to melanin-producing cells. Vitiligo, a disorder characterized by the destruction of melanocytes, is often associated with diseases in which there are increased frequencies of autoantibodies. For this reason we investigated two patients with vitiligo, alopecia universalis, mucocutaneous candidiasis, and multiple endocrine insufficiencies for antibodies to melanin-producing cells. Using direct immunofluorescence of normal and vitiliginous skin from both patients and indirect immunofluorescence with both patients' serum, we could not detect these antibodies. However, an immunofluorescent complement-fixation test demonstrated a circulating antibody that bound to melanocytes in human skin, nevus cells and melanoma cells. Specificity of cellular fluorescence for nevus and melanoma cells was shown on serial sections stained with hematoxylin and eosin and was inferred for melanocytes from their distribution in human skin and their presence when the normal but not vitiliginous skin of both patients was used as substrate. This antibody was characterized as an IgG that activated complement via the classical pathway.


Characterization of immunoglobulin classes of human antibodies to cryptococcus neoformans. Immunoglobulin G (IgG), immunoglobulin M (IgM) and immunoglobulin A (IgA) levels were determined by radial immunodiffusion techniques in sera from 11 patients with cryptococcosis. Most specimens showed increased levels of IgM. Studies with fluorescein-labeled monospecific antihuman IgG and IgM, however, indicated that IgG was the immunoglobulin reactive in the indirect fluorescent antibody (IFA) test. In addition, cross-reacting sera from mycotic infections other than cryptococcosis were also shown to contain IFA antibodies of the IgG class. Sera treated with 2-mercaptoethanol continued to react in both the IFA test and the tube agglutination test. No correlation could be established between IgG AND IgM concentrations and serological reactivity in the sera evaluated in this study.


Why the genome does not congeal.

Why the genome does not congeal. Since the genes in any given organism have evolved together to produce an adaptive phenotype, one might expect that rearrangement by chromosomal recombination would be maladaptive and thus wiped out by natural selection. This article reviews various theories that explain why, on the contrary, recombination is almost universal.


New Miocene locality in Turkey with evidence on the origin of Ramapithecus and Sivapithecus. Collections in early Middle Miocene deposits at Pasalar in Turkey have yielded a very rich fauna. Included in this are two hominoid species referred here to Sivapithecus darwini (Abel) 1902 and Ramapithecus wickeri (Leakey) 1962. These are both more primitive morphologically and earlier in time than other species of these genera, and they provide evdence that Sivapithecus and Ramapithecus are closely related and that their early diversification may have occurred not in Africa but in Eurasia.


Calcitonin levels in chronic renal disease. High levels of serum calcitonin were found in patients with chronic renal failure. Serum calcitonin correlated directly with the phosphate to total calcium ratio; calcitonin levels correlated inversely with serum calcium in those patients on dialysis and directly with serum calcium in nondialysis patients. All patients had elevated serum gastrin. The high levels of serum calcitonin usually decreased following successful kidney transplantation. The pathophysiology of this hypercalcitonemia and its relationship to renal osteodystrophy and the disordered calcium metabolism of uremia remains to be elucidated.


Return of function in the thrombosed kidney after transplantation. The incidence of intraglomerular thrombi in renal allografts and factors regulating their resolution were studied. A case report is presented in which resolution of intraglomerular thrombi is documented. In addition, 17 transplanted patients with renal biopsies were serially studied. Intraglomerular thrombi were found in 4 of 8 specimens taken 1 h after reanastamosis, all from donors with a terminal course involving prolonged hypotension. Glomerular fibrinolytic activity was markedly diminished in 4 of 11 patients' subsequent biopsy specimens; all taken during acute rejection. Resolution of thrombi was documented when signs of rejection were absent.


[Regression of a recurrent malignant glioma by combined chemoradiotherapy utilizing carboquone, FT-207 and telecobalt--report of a case (author's transl)]. Current chemotherapy of malignant brain tumor bases on cell kinetics. Chemotherapeutic agents are devided into two, cell cycle specific (CCS) and cell cycle non specific (CCNS) agents. A case of malignant glioma successfully treated by chemo-radiotherapy using a new combination of the two agents , Carboquone (CQ) as CCNS, which has not appeared in literature, and FT-207 as CCS is reported. A malignant glioma in the right frontal lobe in a case of 51-year-old male was removed subtotaly on Dec. 10th, 1971 in our clinic. Three years and five months after the surgery, the patient was diagnosed as having a recurred  malignant glioma in the left frontal lobe from the clinical symptoms. This was supported by a positive brain scan and carotid angiography. A total dose of 57mg of CQ was continuously into the left internal carotid artery during two months. Simultaneously, 16g of FT-207 as a total dose was given orally and 4,550 rads of Telecobalt-60 were irradiated. One month after the beginning of these treatments, clinical symptoms improved obviously. Four months later, the size of the tumor shadow on the brain scan decreased remarkably and the shifted anterior cerebral artery returned to normal position on the carotid angiogram. Anemia, leucopenia, thrombocytopenia, nausea, and anorexia were the side-effects of these treatments. But these complications disappeared six weeks after the termination of the treatments.


Acute effect of delta1-tetrahydrocannabinol on the hypothalamo-pituitary-ovarian axis in the rat. Administration of delta1-tetrahydrocannabinol (delta1-THC), the principal psychoactive ingredient of cannabis, to proestrous rats (2 mg/rat, i.p., between 12.00 and 16.00 h) suppressed the proestrous rise in the plasma levels of LH, FSH and prolactin (Prl) and caused a 24 h delay in ovulation. Furthermore, the increased accumulation of prostaglandins of the E-type (PGE) in the ovaries, normally seen on the evening of proestrus, was prevented. Earlier (08.00-10.30 h) or later (18.00 h) administration of the drug on the day of proestrus was only partially effective in inhibiting ovulation. The suppressive effects of delta1-THC on ovulation and gonadotropin secretion were prevented by administration of gonadetropin releasing hormone (GnRH, 0.2 microgram/rat) 1 h after the drug, indicating that the central action of delta1-THC was exerted on the hypothalamus and not on the pituitary gland. Administration of ovine luteinizing hormore (oLH, 2.5 microgram/rat at 16.30 h on the day of proestrus restored ovulation and ovarian PGE accumulation in Nembutal-treated rats, but not in delta1-THC-treated rats; higher doses of oLH (5-10 microgram/rat) reversed the action of delta1-THC on these two parameters.


The role of the septal area in the neuroendocrine control of growth in the adult golden hamster. Somatic, endocrine and behavioral correlates of growth were measured in intact and hypophysectomized adult hamsters with or without electrolytic damage to the rostral septal area. Septal (SEP) lesions significantly increased somatic growth rate, food consumption and serum concentration of growth hormone (GH) and insulin. Pituitary GH content and concentration were reduced in lesioned hamsters. None of these changes were found in hypophysectomized hamsters with SEP lesions. SEP lesions did not affect the percentage of body fat. These data suggest that the septum or adjacent fibers of passage inhibit growth in adult hamsters.


Evidence for the dependence of serum luteinizing hormone surge on a transient, enhanced secretion of gonadotropin-releasing hormone from the hypothalamus. Data that a substantial, transient release of gonadotropin-releasing hormone (GnRH) from the hypothalamus is a prerequisite for the serum luteinizing hormone (LH) surge are presented. Ovariectomized rats, in which daily afternoon LH peaks can be induced by estradiol benzoate (EB), were used as the experimental model. These rats present a homogenous, synchronized population having low hypothalamic stores of GnRH, thus facilitating detection of small physiological fluctuations in the levels of hypothalamic GnRH. Blockade, by Nembutal administration, of the serum LH surge on 2 consecutive afternoons results in elevated GnRH levels in the hypothalamus (1.79 ng in blocked rats vs 0.94 ng in controls). Abolition of LH secretion by administration of antiserum to GnRH, unlike the Nembutal blockade, does not affect GnRH levels. These results indicate that the afternoon LH surge is dependent on a transitory, enhanced release of GnRH from the hypothalamus, reflected by a depletion of GnRH stores.


[Serial studies of sterile skin exudate in patients with multiple sclerosis]. In 23 patients with multiple sclerosis (group i) and 15 other subjects (group II) cell content of sterile exudate was studied in the skin window test of Rebuck. The results were compared. Cellular reaction of the skin was greater in group I than in group II and the difference was statistically significant. The number of mononuclear cells was increased especially from 12 to 15 hours after scarification.


Pituitary-gonadal function in heroin addicts. The present study deals with pituitary-gonadal function in male heroin addicts, 6 patients with schizophrenia and 31 with mild personality disorders. We examined the serum follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone levels at the moment of hospitalization (at the maximum of heroin addiction), and 48 h and 10 days later. FSH levels were definitely reduced in all the patients and did not change during the period of heroin withdrawal. The LH levels were reduced to  a lesser extent, but significantly, and did not change after 10 days of abstinence from the drug. Testosterone levels were very low and increased in the schizophrenics during withdrawal, but not in the other addicts. The possible influence of heroin addiction on catecholamine metabolism in the central nervous system and, therefore, on the hypothalamic releasing factor and pituitary gonadotrophins, and the peripheral effect on testicular function are discussed.


Cerebral angiography with non-ionic (metrizamide) and ionic (meglumine metrizoate) watersoluble contrast media. A comparative study with double blind technic. The adverse effects of cerebral angiography with metrizamide and meglumine metrizoate were compared in 20 patients for each contrast medium using a double blind technic. Deterioration of the EEG and bradycardial reactions were seen more often with meglumine metrizoate than with metrizamide and these differences were statistically significant. Metrizamide also had a shorter circulation time, less influence on the blood pressure and EMG than meglumine metrizoate, but these differences were not statistically significant. The clinical examinations showed no difference in the minor adverse effects. One patient had transient hemiparesis and dysarthria after angiography with meglumine metrizoate but no serious complications were seen in the others.


[Acupunctura, "vital" drugs and psychopharmacological agents in the treatment of psychiatric patients with deep depressive disorders, with considerations on the probable neurophysiological mechanisms of the synergism of action]. Personal clinical experience in 36 psychiatric patients with true or masqued depression, receiving a combined treatment of acupuncture (in traditional and auricolar suprarenalic points), "vital" drugs (DPA 300-900 mg/die; l-glutamine 250-500 mg/die) and psycho-drugs (amitryptiline 50 mg/die; clomipramine 10-30 mg/die; diazepam 2-20 mg/die; haloperidol 2 mg/die) is described. 35 out of 36 cases improved by such therapy. Possible synergic mechanisms leading to a considerable reduction of usual phychodrugs, and attenuating or eliminating various side effects are finally discussed.


[Psychological dependence? A possible different formulation of the problem for a therapeutic rearrangement in chronic drug addictions]. Disputing the concept of "psychic dependence", the Authors review six motivations to use addictive drugs, four of which pertain to the moment to assume the habit, although the latter two, which are identifiable with physical and psychic dependence, depend on te breaking the habit. While physical dependence is linked to withdrawal syndrome, psychic dependence, on the Author's opinion, is related to a long-standing previous state of true or masked endogenous depression (in this case it would be well termed as "neuropsychological dependence"), and the drug taking is only a maladaptive self-medication. This thesis is substantiated by the literature, reporting, in chronic drug addicts the use of the whole series of antidepressants (i.e. tricyclics, doxepine, lithium, etc.), with noticeable therapeutical success. According with other reports and with personal experience, the Authors maintain a great importance to drugs acting, directly or not, on GABA, i.e. l-glutamine, piracetam, and, particularly, N-dipropilacetic acid.


[Recent acquisitions in hyaline membrane disease]. Hyaline membrane disease is an important factor in the postnatal mortality of prematures. Its pathogenesis is examined. Prematurity, maternal diabetes, and caesarean section are seen as predisposing causes. Delayed biochemical maturation of the lung (shown by a low lecithin-sphyngomyelin ration in the amniotic fluid and probably caused by hypophyseal-adrenal insufficiency) results in an absence of surfactant. Labour stimulates its production by massive release of endogenous cortisol. The part played by betamethasone and other substances in prophylaxis is discussed. It is felt that, at present, the availability of preformed tensioactive factors alone can achieve the decidedly improved prognosis required in so serious a disease.


Hepatolenticular degeneration (Wilson's disease) and pregnancy. A review and report of a case. This article presents a case report of Wilson's disease in pregnancy and a review of this entity during gestation. Biochemical and pathological data are reviewed and current treatment is discussed. Pertinent questions of interest to the obstetrician are indicated with reference to Wilson's disease.


A double running suture technique for keratoplasty: earlier visual rehabilitation. The technique of using two continuous sutures of different caliber and relative tightness, running in the same direction, is described for penetrating keratoplasties. The primary purpose of the technique is to allow visual correction earlier in the postoperative period. In addition, graft slippage with override and posterior wound gape, both occurring at suture removal with resultant functional loss, have been eliminated.


A technique for treating positive vitreous pressure during intraocular lens implantation in intracapsular surgery. Positive vitreous pressure during intraocular lens implantation is treated by early recognition and instillation of an air bubble to deepen the anterior chamber, and subsequently to prevent contact between the intraocular lens and the corneal endothelium. A technique is presented which has proven successful in 20 cases.


One-day hospitalization for extracapsular cataract surgery without phacoemulsification. A technique is described for an extracapsular cataract extraction that combines the advantage of freedom of activity associated with phacoemulsification without many of the disadvantages of this procedure. The technique retains one of the advantages of a small wound, the use of the irrigating cystotome, with an advantage of a large wound, ease of delivery of a firm nucleus. An intact posterior capsule is maintained. Although it is similar to the one-day intracapsular method that we described, the present procedure preserves the advantages of a well planned extracapsular extraction for the situations in which intracapsular surgery is not desirable. The technique has been used in 25 cases which have been followed longer than nine months, in which there have been no complications nor secondary opacification of the posterior capsule. The desirable and undesirable features of phacoemulsification, classical extracapsular, our extracapsular and intracapsular procedures have been compared. Comparison with the techniques of lens extraction through a pars plana approach is beyond the scope of this paper.


Ophthalmoplegic migraine: amelioration by Flufenamic acid, a prostaglandin inhibitor. It was recently suggested that prostaglandins' release (especially PGE1 and PGF2alpha) play a key role in the development of the migrainous attack. Based on this hypothesis a therapeutic trial with flufenamic acid (a prostaglandin inhibitor of the fenamates group) was conducted during 1 year in 5 patients suffering from recurrent ophthalmoplegic migraine. We treated 25 migrainous attacks; in 22 of them the patients reported marked alleviation of the headaches and only in two occasions a partial third nerve palsy accompanied the attack.


The effect of chlorhexidine mouth rinses on oral Candida in a group of leukemic patients. Eighteen leukemic patients were examined for the presence of Candida albicans in the oral cavity. Fifteen patients were found to be Candida "carriers." Nine of the patients were put on a chlorhexidine mouth rinse regimen. Although chlorhexidine was clearly fungicidal in vitro, no decrease in Candida titer was obtained with the mouth rinse. The ineffectiveness of the drug in vivo might be due to the specific location of Candida organisms in the oral mucosa.


A strip test for detecting Candida in the oral cavity. One-hundred and twenty persons were screened for the presence of Candida in the mouth. Salivary samples were cultured on Sabouraud's agar, on yeast extract, and on Microstix. Microstix is a new and simple method testing for Candida. The reliability of the strip for detecting clinically identified candidiasis in severely ill patients was 100 per cent. Of ninety-three clinically healthy controls, forty-five were found to be Candida carriers according to the two conventional methods (Sabouraud's agar and yeast extract), but only forty-one of them by the strip. The discrepancy might be explained by the limit of the sensitivity of the strip (5.10(2) yeast per milliliter). The strip is recommended for testing clinically suspected candidiasis and is very useful for screening.


Experimental evaluation of microsurgical techniques in small artery anastomoses. A number of factors that influence the success of microvascular anastomosis have been studied, including adventitial stripping, choice of suture material and needles, suturing technique, and perfusion of the distal lumen. It is apparent that only minimal stripping of the adventitia is indicated in order to prevent increased necrosis of the vessel ends at the anastomosis site. The use of 10-0 monofilament nylon suture material with needles 75 microns or less in diameter achieves the best results in small vessel anastomoses. Optimal anastomosis of 1 mm. vessels requires interrupted full thickness sutures with minimal adventitial stripping and the use of the smallest number of sutures possible. We do not advocate routine perfusion of small arteries unless there are specific indications. An experienced team of microsurgeons utilizing these principles along with proper patient selection and a sound postoperative regimen should be able to achieve more than a 70 per cent success rate in replantation of completely amputated digits and hands.


Evaluation of digital replantation--a review of 100 cases. One hundred digital replantations and revascularizations of digits performed during a five year period were analyzed. Seventy replantations (70 per cent) survived and 62 were available for long term functional follow-up. Provided strict indications are observed, replantation is a most worthwhile procedure.


Practical microneurorrhaphy.

Practical microneurorrhaphy. Microneurorrhaphy is not a panacea insuring excellent functional return following severance of a nerve. However, it does provide better results than macroneurorrhaphy. Patients note greater and stronger motor recovery, improved protective sensation, improved touch localization, and fewer painful neuromas if the principles of neurorrhaphy outlined are followed. Unfortunately "normal function" is seldom achieved, and this fact points to the necessity for additional knowledge about peripheral nerve repair.


The origin of the planetesimal theory.

The origin of the planetesimal theory. T. C. Chamberlin suggested in 1897, on the basis of geological and climatological arguments, that the planets were formed by accretion of cold solid partices. With F. R. Moulton he developed convincing arguments against the Laplace nebular hypothesis and published a comprehensive 'planetesimal theory' of the origin of the solar system in 1905. The Chamberlin-Moulton theory has current as well as historical interest.


The paediatric syndrome of traumatic myelopathy without demonstrable vertebral injury. Three detailed case histories are added to those previously published in the literature and from the evidence now available a proposal is made that a paediatric syndrome of traumatic myelopathy without demonstrable vertebral injury be recognised as a definite clinical entity. The mechanisms of injury, evolution, patterns of paralysis and pathological evidence are discussed. The conclusion is drawn that no form of treatment yet known can influence the prognosis in this syndrome.


[Incidence of clonorchiasis in carnivorous animals in upper Priamur'e]. In Upper Priamurje domestic and wild mammals were examined for the infection with Clonorchis sinensis. It was found that in the south--eastern regions of the Amur district 45.8% of cats were infected with Clonorchis sinensis was recorded only from two animals.


Meconium aspiration syndrome.

Meconium aspiration syndrome. Meconium aspiration syndrome is a perinatal problem which requires the full cooperation and coordination of obstetrical and pediatric personnel if it is to be avoided. Prompt, efficient delivery room management can minimize the sequelae of aspirated meconium. However, those infants who develop severe meconium aspiration syndrome are best managed in neonatal intensive care units where they can be closely monitored and vigorously treated.


Fluid and electrolyte requirements in the newborn infant. Most of the studies of water and electrolyte balance have been performed on full teren balancing the hydration and electrolyte status of all infants, it is most important to relate the treatment regimen to the infant's gestational age and weight, and to make appropriate adjustments for various environmental conditions which affect water and salt requirements, such as phototherapy, type of warmer, and humidity.


Acute renal failure in the neonate.

Acute renal failure in the neonate. With advances in diagnostic technology, the diagnosis of renal failure from prerenal and renal causes is being made more frequently. With better clinical understanding of etiologic causes, early prevention and diagnostic and therapeutic measures can be taken. Proper and controlled use of fluids, calories, and drugs is essential. Because of its relative ease, peritoneal dialysis is usually preferred over hemodialysis when renal failure cannot be handled more conservatively. Although the incidence of renal failure has apparently increased with the advent of neonatal intensive care, survival rates are increasing and the potential for prevention is better.


Predominant of exclusive orbital and facial involvement in infantile cortical hyperostosis (de Toni-Caffey's disease). Report of four cases and a review of the literature. Four patients who presented with predominant or exclusive face and orbital involvement by de Toni-Caffey's disease are reported. Facial manifestations of infantile cortical hyperostosis may be the first and sometimes the only manifestion of the disease. A mandibular involvement is almost always present and its characteristic appearance leads to the diagnosis of de Toni-Caffey's disease.


Chronic pulmonary disease in neonates after artificial ventilation: distribution of ventilation and pulmonary interstitial emphysema. To determine pulmonary function abnormalities in patients with neonatal bronchopulmonary dysplasia (BPD), we measured distribution of ventilation by nitrogen washout, minute and tidal volume, and arterial and alveolar gases in three groups of ten preterm infants with similar birth weights (mean = 1,340 g) and gestational ages (mean = 30.3 weeks). Infants in group A were never artificially ventilated, those in group B were ventilated but had no subsequent BPD, and those in group C were ventilated and developed BPD. Infants with BPD had severe maldistribution of ventilation (pulmonary clearance delay 223% versus 47% and 60% for groups A and B). They had decreased tidal volumes (5.3 ml versus 7.0 and 6.2 ml) and higher respiratory rates (60/min versus 47 and 48) but similar minute volumes. They also had increased PaCO2 (53.6 torr versus 41.9 and 43.4 torr) and increased arterial-alveolar carbon dioxide gradients (6.8 torr versus 3.1 and 1.8 torr). There was no statistically significant difference between groups B and C for the time spent in fractional inspired oxygen greater than 0.40 and greater than 0.60, or the time ventilated for intubated, or the incidence of patent ductus arteriosus. Early pulmonary interstitial emphysema was much more common in the infants who subsequently developed BPD (eight of ten versus two of ten, P less than .01).


Natural history of neonatal colonization with group B streptococci. Thirteen percent of the newborns in our study group were colonized with group B streptococci on day 3. This colonization rate appeared constant during the first two weeks of life and then decreased to 5%. Of the babies colonized on day 3, 59% and 91% were culture-negative on days 14 and 42, respectively. Sixty-five percent of the babies carrying group B streptococci on day 14 acquired this microorganism following discharge (day 3). Babies colonized with staphylococci or Escherichia coli were found to have decreased probability of colonization with group B streptococci.


Significance of radiographic findings in early-onset group B streptococcal infection. Chest radiographs on 73 neonates with early-onset group B Streptococcus (GBS) infection were reviewed. Eighty-six percent of the infants were premature (less than 38 weeks); 68% weighed less than or equal to 1,500 g. In infants weighing less than or equal to 1,500 g, the predominant radiographic pattern was hyaline membrane disease (HMD) (80%). There was a significant increase in radiographic HMD in 1,000 to 1,500-g neonates with GBS infection (77%) when compared to a control group of infants without GBS infection (44%). Mortality in 1,000 to 1,500-g infants with GBS infection and radiographic HMD (95%) was also significantly higher than in the control group of infants with hmd HMD and no GBS infection (38%). In larger premature and full-term infants, the radiographic findings were not specific and also were not helpful in distinguishing GBS infection from other newborn respiratory disorders.


Survival of Mycobacterium paratuberculosis in slurry. Cattle and swine slurry and a mixture of equal parts of both, was mixed with a culture of M. paratuberculosis, 0.1 mg per ml (1 mg = 33 X 10(6) viable units) and stored under anaerobic conditions at 5 degrees and 15 degrees C. At 5 degrees C the survival time for M. paratuberculosis was 252 days in all 3 kinds of slurry, and at 15 degrees C it was 98 days in cattle slurry, 182 days in swine slurry, and 168 days in mixed slurry.


[Serum and urinary antibodies in pyelonephritis (author's transl)]. Pyelonephritis is accompanied by complex immunological reactions, the study of which is just now being undertaken. Study of 216 patients with a significant monomicrobial urinary infection showed that in more than 95 per cent of cases of Gram negative infection the urine contained IgG type antibodies, often associated with IgA. These antibodies may be easily detected using an immunofluorescent technique, which would appear to be the best method available at present for distinguishing between pyelonephritis and an infection of the lower urinary tract. They may also be found in the serum, though less frequently. Detection by immunofluorescence is markedly more sensitive than using the classical passive haemagglutination technique. The biological significance of these antibodies remains imprecise, and their protective or facilitating role may be discussed. Their specificity must be determined, in order that sequential study of these immunological reactions may be of help in the conduct of treatment.


[Combined immunological and cytochemical identification of nucleated cells in normal human peripheral blood]. Nucleated cells obtained from normal human peripheral blood on a layer of Ficoll Isopaque are identified according to the combination of various assays: phagocytosis, endogenous peroxidase, naphtol AS-D esterase, immunofluorescence (IF) performed at 4 degrees C and after incubation at 37 degrees C. The Ig bearing lymphocytes are evaluated with IF, while errors due to other nucleated cells may be evaluated by phagocytic and enzymatic capacities. As the presence of immunoglobulins (Ig) on the cell surface doses not prove its B lymphocytic nature, both immunofluorescence (IF) and endogenous peroxidase are usefully performed together. Exposure of the cells to 37 degrees C during half an hour may enable us to avoid to consider monocytes and lymphocytes with cell bound Ig. Thus con accurately be evaluated the percentages of lymphocytic populations in practice of immunological tests.


Supercoiling energy and nucleosome formation: the role of the arginine-rich histone kernel. We have formed complexes of relaxed closed circular Col E1 DNA with various combinations of histones, and examined the effects of treating the complexes with nicking-closing enzyme. Germond et al (1) have shown that when a mixture of the four core histones of the nucleosome (HIA, H2B, H3 and H4) is used in such an experiment, the subsequently isolated DNA is supercoiled. We find that the arginine-rich histone pair, H3 and H4, is sufficient to induce the supercoiling observed in this experiment. Both H3 and H4 are required, and in the absence of either, no other histones are effective. H3 and and H4 are as efficient, per unit weight, as a mixture of the four histones in inducing supercoils. We also show that there is a large difference between the DNA bending energy needed to form a nucleosome and that needed to form one turn of normal superhelical DNA. These two processes are energetically quite distinct and probably separable. We estimate the free energy of interaction between DNA-bound histone pairs, and find that one or two such interactions would generate enough energy to fold the DNA into a nucleosome.


Studies of ColE1-plasmid DNA and its interactions with histones: sedimentation velocity studies of monodisperse complexes reconstituted with calf-thymus histones. Complexes between the four calf-thymus histones (H2A, H2B, H3 and H4) and colE1-plasmid DNA have been reconstituted using the procedure of Oudet et al. ((1975), Cell 4, 281-300). The sedimentation rates of the complexes formed were studied under a variety of conditions. In 0.4 MNaCL, 0.1 M Tris pH 7.50, 0.01 M EDTA and 0.02 M NaHSO3, the final dialy-sis-solvent in the reconstitution procedure, the sedimentation coefficients s23 were found to increase when the complexes were reconstituted at increasing histone to DNA ratios. True plateau regions were reached in the case of the relaxed circular and linear forms of the plasmid DNA. The sedimenting boundaries observed for the complexes at saturation are sharp, reflecting a narrow distribution of sedimentation coefficients and a homogeneity of the complex comparable to that of the uncomplexed DNA. Studies of the dependence of s 23 on the concentration of the complex at constant DNA to histones ratio have been undertaken at salt concentrations between 0.4 and 1.5 M NaCL in the above solvent. The formation of the complexes is reversible, at least at the higher ionic strengths. At salt concentrations below 0.36 M the complex precipitates from solution. Omission of histone H4 from the reconstitution mixture abolishes complex formation.


Physiochemical studies on interactions between DNA and RNA polymerase. Unwinding of the DNA helix by Escherichia coli RNA polymerase. In a medium containing 10mM Tris, pH 8, 10 mM MG++, 50 mM K+ and 10 mM NH4, the binding of an E. coli RNA polymerase holoenzyme unwinds the DNA helix by about 240 degrees at 37 degrees C. In this medium the total unwinding of the DNA increases linearly with the molar ratio of polymerase to DNA. The number of binding sites at which unwinding can occur is very large. If the K+ concentration is increased at 200 mM, the enzyme binds to only a limited number of sites, and the bound and free enzyme molecules do not exchange at an appreciable rate. The unwinding angle of the DNA per bound enzyme in this high salt medium is measured to be 140 degrees at 37 degrees C. The total unwinding angle for a fixed number of bound polymerase molecules per DNA is strongly temperature dependent, and decreases with decreasing temperature.


A restriction endonuclease cleavage map of mouse mitochondrial DNA. A restriction endonuclease cleavage map is presented for mouse mitochondrial DNA. This map was constructed by electron microscopic measurements on partial digests containing fixed D-loops, and by electrophoretic analysis of partial and complete single enzyme digests, and of double digests. No map differences were detected between mitochondrial DNA from cultured LA9 cells and an inbred mouse line for the six endonucleases used. Three cleavage sites recognized by HpaI, five sites recognized by HincII, two sites recognized PstI and four sites recognized by BamI were located with respect to the origin of replication and the EcoRI and HinIII sites previously determined by others. No cleavages were produced by KpnI or SalI. The migration of linear DNA with a molecular weight greater than 1 X 10(6) was not a linear function of log molecular weight in 1% agarose gels run at 6.6 volts/cm.


Restriction endonuclease cleavage maps of rat and mouse mitochondrial DNAs. Mitochondrial DNA from an Old World mouse, Mus musculus, and from an Old World rat, Rattus norvegicus, contain 19 and 22 distinct sites, respectively, for the 8 restriction endonucleases, BamHI, EcoRI, HaeII, HhaI, HincII, HindIII, HpaI and PstI. The relative positions of the sites have been mapped by the study of partial and double enzyme digests. Some sites may been conserverd between the mouse and rat mitochondrial genomes.


Microheterogeneity detected in circular dimer mitochondrial DNA. Exhaustive EcoRI digests of circular dimer mitochondrial DNA (mtDNA) from mouse cell lines LD and LDTK- yield two major fragments whose average lengths are slightly smaller than the corresponding fragments of circular monomer mtDNA from mouse LA9 and LMTK- cells. A third fragment approximately 400 nucleotide pairs in length is frequently produced in less than molar yield. Exhaustive EcoRI digests of circular dimer mtDNA from human acute myelogenous leukemic leucocytes yield three major fragments. The presence of mtDNA resistant to cleavage as well as fragments of intermediate sizes indicatesmicroheterogeneity in the genomic positions of EcoRI recognition sequences in both mouse and human circular dimer mtDNA. Analysis of the distribution averages of circular contour lengths indicates microheterogeneity in the sizes of mouse LD and human mtDNAs. The denatured-renatured EcoRI fragments frequently contain a small loop(s) of single-strand DNA as would occur for deletion(s) or addition(s) of single-strand DNA as would occur for deletion(s) or addition(s) of nucleotide sequences in some of the circular dimer molecules.


Analysis of chromosomal integration and deletions of yeast plasmids. Plasmid DNAs from six strains of Saccharomyces cerevisiae were compared. Three different plasmids were found, designated Scp 1, Scp 2 and Scp 3, with monomer lengths of 6.19, 6.06 and 5.97 kilobases as referenced to sequenced phiX174 DNA. DNA from each of the plasmids was inserted into a lambda vector DNA. Hybrid phage containing inserted DNA of the desired size were enriched by genetic selection and their DNAs analysed by rapid techniques. All three plasmids share the same organization, two unique sequences separated by two inverted repeats, and share basically the same DNA sequences. Scp 2 and Scp 3 differ from Scp 1 by missing a unique HpaI site and by having small overlapping deletions in the same region. The HpaI site in Scp 1 is, therefore, in a nonessential region and suitable for insertion of foreign DNA in the potential use of the yeast plasmid as a vector. Hybridization of labelled cloned plasmid DNA to restriction fragments of linear yeast DNA separated on agarose gels showed that the plasmid DNA was not stably integrated into the yeast chromosomal DNA.


Physical properties and gel electrophoresis behavior of R12-derived plasmid DNAs. A series of closed circular (I) plasmid DNAs has been derived from drug resistance factor R12, and the nicked circular (II) and linear (III) derivatives of these molecules prepared by irradiation in the presence of ethidium bromide and by treatment with restriction enzyme EcoRI, respectively. These DNAs encompass the molecular weight range 3.6 to 61 megadaltons. The base compositions range from 45% to 51% (GC) as estimated by buoyant density determinations. The smaller plasmids are significantly less supercoiled (9-10%) than are the larger (12-13%). The gel electrophoretic behavior of the three DNA structural forms was determined as a function of molecular weight in agarose gels of concentrations ranging from 0.7% to 1.6% and at electrophoresis salt concentrations from 0.02 M to 0.08 M sodium acetate. The mobilities of DNAs I and III undergo a reversal relative to each other at a molecular weight which decreases with increasing agarose gel concentration. The molecular weight at which DNA II fails to enter a gel depends upon the ionic strength during electrophoresis but not upon the gel concentration.


Separation of the complementary strands of DNA fragments on polyacrylamide gels. 32P-labeled (in vivo) phiX174 RFI DNA was restricted by Hinc II. Three aliquots of the same digest: a) nondenatured, b) heat denatured, and c) denatured by 5 mM Me-HgOH were analyzed on 3-15% acrylamide gel gradients or on 3% gels with reduced N,N'-methylene-bis-acrylamide. The autoradiography of the gels showed that the nondenatured sample migrates two times faster than the denatured samples. After denaturation each original fragment appeared as a doublet. Using in vitro synthesized RFI DNA labeled only in negative strand with 32P we could identify the position of the negative strand in each denatured doublet. The single strand DNA fragments could be recovered from the gel slices on a semi-preparative scale by electrophoresis into dialysis tubing.


Binding of E.coli lac repressor to non-operator DNA. It is shown by melting profile analysis of lac repressor-DNA complexes that repressor binds tightly and preferentially (relative to single-stranded DNA) to double-stranded non-operator DNA. This binding stabilizes the DNA against melting and the repressor against thermal denaturation. Analysis of the extent of stabilization and the rate of dissociation of repressor from non-operator DNA as a function of sodium ion concentration shows, in confirmation of other studies,(3,4) that the binding constant (K(RD)) is very ionic strength dependent; K(RD) increases from approximately 10(6) M(-1) at approximately 0.1 M Na(+) to values in excess of 10(10) M(-1) at 0.002 M Na(+). Repressor bound to non-operator DNA is not further stabilized against thermal denaturation by inducer binding, indicating that the inducer and DNA binding sites probably represent separately stabilized local conformations. Transfer melting experiments are used to measure the rate of dissociation of repressor from operator DNA. These experiments show that most of the ionic strength dependence of the binding constant is in the dissociation process; the estimated dissociation rate constant decreases from greater than 10(-1) sec(-1) at [Na(+)] >/= 0.02 M to less than 10(-4) sec(-1) at [Na(+)] </= 0.002 M. Competition melting experiments are used to show that at 0.02 to 0.002 M Na(+) the affinity of lac repressor for various natural DNAs and synthetic double-stranded polynucleotides (including poly[d(m(6)A-T)], which carries a methyl group in the large groove) are approximately independent of base composition, except that the affinity of repressor for poly[d(A-T)] is approximately 2- to 3-fold greater than for the other DNAs tested. The affinity for single-stranded polynucleotides is atleast 50-fold less than for the doublehelical forms.


Complementary addressed modification of yeast tRNA Val 1 with alkylating derivative of d(pC-G)-A. The positions of the alkylated nucleotides and the course of the alkylation in the complex. Yeast tRNA Val 1 alkylation with 2', 3'-O-4-(N-2-chloroethyl-N-methylamino) benzylidene d(pC-G)-A proceeds at 20 degrees - 30 degrees C in the complementary complexes which are formed by d(pC-G)-A greater than RC1 binding to 3 sequences of tRNA Val 1 : psi-C-G58 in the T loop, C-G40 at the 3'-side of the anticodon loop and C-G18 in the D loop. The reaction in the complexes results in A53, I35, and psi 13 alkylation to form beta-/N-methyl-N-(formylphenyl 17 amino/ethyl-tRNA Val 1 with the relative rate constants of the alkylation that are 3 or 2 orders of magnitude higher than that for the alkylation without a complex formation. It is the third nucleotide from the 5'-terminus of the binding site of the modifying agent that is subjected to alkylation in the t RNA Val 1. The course of the alkylation does not depend on the possible base pairing of the 3'-terminal nucleotide of the reagent. The extent of the reagent binding and the relative rate constants of the alkalytion in the complexes indicate the following order of the complex stability: (psi-C-G58) greater than (CO-G40) approximately (C-G18) at 20 degrees and (psi-C-G58) greater than (C-G40) greater than (C-G18) at 30 degrees.


Structural organization of complexes of transfer RNAs with aminoacyl transfer RNA synthetases. A variety of experimental data on synthetase-tRNA interactions are examined. Although these data previously had no direct explanation when viewed only in terms of the tRNA cloverleaf diagram, they can be rationalized according to a simple proposal that takes account of the three dimensional structure of tRNA. It is proposed that a major part of the binding site for most or all synthetases is along and around the diagonal side of the tRNA structure, which contains the acceptor stem, dihydrouridine stem, and anticodon. This side of the tRNA molecule contains structural features likely to be common for all tRNAs. Depending on the system, an enzyme may span a small part or all of the region of this side of the molecule. Interactions with other parts of the structure may also occur in a manner that varies from complex to complex. These interactions may be determined, in part, by the angle at which the diagonal side of the flat tRNA molecule is inserted onto the surface of the synthetase.


A strong ethidium binding site in the acceptor stem of most or all transfer RNAs. E. coli unfractionated tRNA and tRNA phe both contain a single strong ethidium binding site. Singlet-singlet energy transfer has been used to measure the distance between this site and dansyl hydrazine covalently attached to the 3' end of the tRNAs. The distance obtained is between 33 and 40 A for both samples. This is completely consistent with results from earlier NMR studies which placed the single, strong ethidium binding site of yeast tRNAphe between base pairs 6 and 7 on the aminoacyl stem. From the known tertiary structure of tRNAphe it is possible to rationalize the unusual affinity of this site and its likely existence in all tRNAs.


Analogs of methionyl-tRNA synthetase substrates containing photolabile groups. Three photolabile analogs of substrates of methionyl-tRNA synthetase were synthesized. In one, the 4-thiouridine at the 8 position of E. coli tRNAfMet was alkylated with [14C]p-azidobromoacetanilide. In the second, [14C]p-azidobenzoic acid hydrazide was condensed with the 3'-terminal dialdehyde of periodate-oxidized Escherichia coli tRNAfMet. The modified tRNAs could be purified by chromatography on benzoylated DEAE-cellulose. The third photolabile compound was [3H]methioninyl-8-azido-adenosine 5'-phosphate, an analog of the methionyl adenylate intermediate in the aminoacylation reaction. Irradiation of each of these compounds in the presence of equimolar amounts of E. coli methionyl-tRNA synthetase of micrometer concentrations gave 5-15% crosslinking.


Inhibition of transcription of supercoiled PM2 DNA by carbodiimide modification. PM2 superhelican DNA (form I), which as been reacted with the single strand specific reagent, N-cyclohexyl-N'-beta-(methylmorpholinium)ethyl carbodiimide (CMC) is more than 95% inhibited in its ability to support transcription with E. coli B RNA polymerase in vitro. Almost complete inhibition of transcription was achieved after 2 hours of reaction with FI when only 1% of the bases were modified. A large increase in S20,* (from 26.8 S to 33.6 S) of FI DNA was observed during the course of reaction. Rifampicin resistant transcription is more susceptible to inhibition by CMC than total transcription, suggesting that the CMC is preferentially binding at promoter sites. These results clearly are in accord with the observation that supercoiled DNA contains localized regions of unpaired bases. The promotor sites for E. coli RNA polymerase in FI PM2 DNA appear to be located at or near these unpaired sites.


Alterations of tRNA modification in mammalian systems: the effect of ethionine. The relationship between the modification of tRNA and its ability to act as a substrate for homologous tRNA modification enzymes in vitro was studied. The tRNA extracted from the livers of rats was active as a substrate for in vitro methylation with extracts from normal rat liver 19 h after treatment with L-ethionine (35 mg/100 g/24 h). After 4 weeks of feeding a diet containing o.25% DL-ethionine, the tRNA was a poor substrate for methylation in vitro, even though it was deficient in methylated nucleosides. Only 18% and 7% of the available sites could be methylated after 67 h and 4 weeks, respectively, of ethionine treatment. 3-(3-amino-3-carboxypropyl)uridine, a nucleoside that is also synthesized from S-adenosylmethionine, was assayed in individual tRNAs by their reactivity with the N-hydroxysuccinimide ester of phenoxyacetic acid. The reactivity of tRNAIle, tRNAAsn, and tRNAThr was decreased by treatment with ethionine at 67 h as well as at 2 and 4 weeks, although no difference could be detected at 19 h.


Biosynthesis of tRNA in histidine regulatory mutants of Salmonella typhimurium. HisU mutants of Salmonella typhimurium are depressed in the histidine operon since they have lower intracellular concentration of histidyl-tRNAHis. In this paper we present evidences showing that a strain carrying a hisU mutation (hisUl206) is altered in a nucleolytic enzyme involved in tRNA maturation process. The analysis of several hisU mutants indicates that hisU region of bacterial genome may account for more than one function involved in tRNA biosynthesis.


Use of specific endonuclease cleavage in RNA sequencing. Nonradioactive RNA fragments may be sequenced by incorporation of (3H)-label into 3'-terminal positions, controlled digestion with specific ribonucleases, and separation according to size of the digestion products on polyethyleneimine- (PEI-) cellulose thin layers. This combination of techniques allows one to measure accurately distances of specific cleavage sites from the labeled terminal positions. The cleavage specificities of RNases T1, U2, and A are utilized to identify the positions of G, A, and pyrimidine residues respectively. C and U may be distinguished by mobility differences on PEI-cellulose thin layers at ph 2.6. The procedure is simple, rapid, and highly sensitive; as little as 0.5 - 1 microgram of a RNA of the size of tRNA will be needed to sequence all fragments in a complete RNase digest.


Rabbit liver tRNA1Val:II. unusual secondary structure of T psi C stem and loop due to a U54:A60 base pair. In contrast to all other known tRNAs, mammalian tRNA1Val contains two adenosines A59 and A60, opposite to U54 and psi 55 in the U psi CG sequence of the T psi C loop, which could form unusual A:U (or A: psi pairs in addition to the five "normal" G:C pairs. In order to measure the number of G:C and A:U (A: psi) pairs in the T psi C stem, we prepared the 30 nucleotide long 3'-terminal fragment of this tRNA by "m7G-cleavage". From differentiated melting curves and temperature jump experiments it was concluded that the T psi C stem in this fragment is in fact extended by an additional A60:U54 pair. A dimer of this fragment with 14 base pairs was characterized by gel electrophoresis and by the same physical methods. An additional A:U pair in the tRNA1Val fragment does not necessarily mean that this is also true for intact tRNA. However, we showed that U54 is far less available for enzymatic methylation in mammalian tRNA1Val compared to tRNA from T-E. coli. This clear difference in U54 reactivity, together with the identification of an extra A60:U54 pair in the U psi CG containing fragment suggests the presence of a 6 base pair T psi C stem and a 5 nucleotide T psi C loop in this tRNA.


Assessment of cardiac blood pools in radiocardiography by various indicator dilution models. Heart blood pools were evaluated by different indicator dilution models from single detector 113mIn radiocardiographic measurements on healthy subjects. It appeared that generally accepted mathematical expressions based on the nth moments of the radiocardiographic dilution curve overestimate the heart volumes by 30-40%. The study suggests that the indicator dispersion within the heart chambers is an essential parameter affecting the central circulatory dilution process, which ought to be included in the radiocardiographic models. Dispersion models based on the random walk equation, probability density function and the gamma variate model produced consistent heart volumes. The suitability of the dispersion models for clinical routine use is discussed briefly.


[Liebow desquamative interstitial pneumopathy. Review of the literature; discussion of a new case]. After a new observation, the authors make as complete a review as possible of the literature on this disease right up to the end of June 1974. They counted 104 observations and analyzed 91 of them. They think the clinical description could be enlarged to include the extra-thoracic signs. Similarly they point at biological peculiarities which unfortunately have only been looked for in a small number of the observations. Out of 77 cases they draw the main evolutive lines of the disease treated or untreated, debating on the reaction to corticosteroids. Finally they debate on the pathogenic hypotheses mainly on histological grounds.


[Pleural effusions (chylous or nonchylous) with regional osteolysis: A case evocative of Gorham's disease]. In connection with one case of thoracic localized osteolysis associated to bilateral seral effusion, serohemorrhagic on the right, chylous on the left, the authors recall 13 similar observations. In this localization a pleural effusion is very frequent and specific to it, putting at stake the vital prognosis of the patient. These observations can be compared to multiple osteolyses and be grouped together under the name of "intraosseous capillary ectasies".


[Histological changes in renal transplants]. The main histological alterations observed in renal transplants, based on a short review of the medical literature and the Pathology Department of the General Hospital (National Medical Center. Mexican Institute of the Social Security) own experience, are reported.


Interaction of rabbit reticulocyte ribosomes with bacteriophage f1 mRNA and of Escherichia coli ribosomes with rabbit globin mRNA. We have compared the behavior of a prokaryotic mRNA in a eukaryotic ribosome binding system and of a eukaryotic mRNA in a prokaryotic ribosome binding system. Using (32)P- and (125)I-labeled bacteriophage f1 mRNA, we have shown that rabbit reticulocyte 80S ribosomes can protect specific sequences from pancreatic RNase digestion, including those sequences protected by Escherichia coli ribosomes. We have also found that E. coli ribosomes fail to protect any region of (125)I-labeled globin mRNA. Iodination of the mRNA appeared to have little or no effect on the specificity of binding or protection by the ribosomes of either system.The eukaryotic and prokaryotic systems differ markedly in the ability of the small ribosomal subunits to protect mRNA from nuclease digestion. The regions of phage f1 mRNA protected by E. coli 30S subunits are virtually identical to those protected by the 70S ribosomes. By contrast, rabbit reticulocyte 40S subunits protect substantially larger fragments of mRNA from nuclease digestion than do the 80S ribosomes. These 40S-protected fragments are specific in the case of globin mRNA and overlap the shorter region protected by the 80S ribosomes. However, the 40S-protected fragments of phage f1 mRNA were found to be extremely heterogeneous, reflecting perhaps an important difference between the initial interactions made by these two mRNAs with the ribosomes.


Identification of spacer tRNA genes in individual ribosomal RNA transcription units of Escherichia coli. Transfer RNA genes ("spacer tRNA genes") are present in the spacer region between 16S and 23S rRNA genes in Escherichia coli. We have analyzed spacer tRNA genes carried by seven rRNA operons with different chromosomal locations. Six of these were isolated on plasmids and one on a transducing phage. We found that, in addition to the two previously identified genes for tRNA2Glu and tRNAIIle, there is a spacer tRNA gene which codes for tRNAIBAla. Of the seven rRNA operons studied, three had both tRNAIBAla and tRNAIIle genes, and the remaining four had the tRNA2Glu gene in their spacers. In addition, genes for tRNAIAsp were found near the distal ends of two different rRNA operons.


Expression of petite mitochondrial DNA in vivo: zygotic gene rescue. A protocol is introduced for probing the organization and regulation of expression of the yeast mitochondrial genome, termed "zygotic gene rescue." The procedure is based on the notion that genes retained on mitochondrial DNA of on the notion that genes retained on mitochondrial DNA of petites can be expressed in zygotes of a cross between petite and wild type. To test the validity of this notion, we have taken advantage of our ability to discriminate, by mobility differences on sodium dodecyl sulfate/polyacrylamide gels, different forms of the product of alleles of the mitochondrial gene, varI. In petite strains that have retained the varI gene, its characteristic product appears in zygotes 4-5 hr after mating; no product is observed in petite strains deleted in the varI locus. Our studies indicate that (i) expression in the zygote of the varI gene in the petite genome is not exclusively the result of recombination with mitochondrial DNA of the wild-type tester, and (ii) the varI gene is probably reiterated in the petite mitochondrial genome. The strength of the technique of zygotic gene rescue in the analysis of the mitochondrial genome is discussed.


Mutagenicity and cytotoxicity of benz[alpha]anthracene diol epoxides and tetrahydro-epoxides: exceptional activity of the bay region 1,2-epoxides. Three diastereomeric pairs of diol epoxides, two tetrahydro-epoxides, and the K-region oxide of the polycyclic aromatic hydrocarbon benz[a]anthracene were evaluated for mutagenic activity in strain TA 100 of Salmonella typhimurium and in line V79-6 of Chinese hamster lung cells. The two diastereomeric 1,2-epoxides of the trans-3,4-dihydrodiol of benz[a]anthracene are 15 to 35 times more mutagenic to the bacteria and 65 to 125 times more mutagenic to the mammalian cells than are the diastereomeric pairs of benz[a]anthracene-8,9-diol-10,11-epoxides or benz[a]anthracene-10,11-diol-8,9-epoxides. 1,2-Epoxy-1,2,3,4-tetrahydrobenz[a]anthracene is the most mutagenic and cytotoxic of the nine derivatives and is 5 and 25 times more mutagenic than 3,4-epoxy-1,2,3,4-tetrahydrobenz[a]anthracene in bacterial and mammalian cells, respectively. In either test system, benz[a]anthracene 5,6-oxide (K-region oxide) has less than 10% of the activity of any of the 1,2-epoxides derived from benz[a]anthracene. The relative stabilities of the derivatives in aqueous solution do not account for the differences in mutagenic activity because the more mutagenic derivatives tend to be less stable. The benz[a]anthracene diol epoxides, like the benzo[a]pyrene diol epoxides, are refractory to the action of epoxide hydrase. The exceptional mutagenic activity of the 1,2-epoxide derivatives of benz[a]anthracene is consistent with and supportive of the hypothesis that bay region epoxides on saturated, angular benzo-rings of unsubstituted polycyclic aromatic hydrocarbons are ultimate carcinogens.


Release of Escherichia coli DNA from membrane complexes by single-strand endonucleases. Treatment of gently prepared lysates of Escherichia coli with single-strand-specific endonuclease (SI or from mung beans) results in the release of about 90% of the DNA from membranes, as determined by the M band technique. The released DNA has an average molecular weight of about 1.2 X 10(8). Data obtained with endonuclease S1 fit a mathematical model in which substrate sites are at or near membrane attachment sites. Data obtained with pancreatic deoxyribonuclease or x-rays fit a model for double-strand breaks at random sites along the DNA. Fitting data to these models, we estimate that there are 18+/-5 membrane attachment sites. The DNA remaining after S1 nuclease treatment is enriched for the region near the origin of chromosome replication. Therefore, attachment at this region near the origin of chromosome replication. Therefore, attachment at this region appears to be chemically different from that at the other sites along the DNA.


Extracellular labeling of nascent polypeptides traversing the membrane of Escherichia coli. To provide direct evidence for the hypothesis that secreted proteins may traverse membranes as growing chains, we labeled spheroplasts of Escherichia coli with a reagent (acetyl[35S]methionyl methylphosphate sulfone) that reacts with amino groups but does not cross the membrane. After fractionation, about 6% of the label in the membrane-polysome fraction was found to be attached to the polysomes. This attachment was via peptidyl-tRNA, as shown by several tests: release of most of the label from purified polysomes at low Mg2+; subsequent loss of about 25,000 daltons on cleavage by dilute alkali; release by puromycin; and release, accompanied by a marked increase in average molecular weight, on peptide chain completion. Moreover, a significant fraction of the completed chains was identified serologically and by molecular weight as a major periplasmic protein, alkaline phosphatase [orthophosphoric-monoester phosphohydrolase (alkaline optimum); EC 3.1.3.1]. This work provides direct evidence that: (i) secreted proteins thread through the membrane as growing peptide chains; and (ii) membrane-associated polysomes in bacteria are functionally attached to membrane and not merely trapped on disruption of the cell.


Isolation of folded chromosomes from the yeast Saccharomyces cerevisiae. Two fast-sedimenting chromatin complexes with sedimentation velocities of approximately 4600 and 3000 S can be isolated from logarithmically growing diploid Saccaromyces cerevisiae cells. The DNA in both structures appears to be folded into at least 60 domains and characterized by a negative superhelical density. Sensitivity to proteases and insensitivity to RNases suggest that proteins and not RNA are important in maintaining the organization of the chromosomes in both structures. The 46000S and 3000S complexes represent folded genomes isolated from diploid cells in the G2 and G1 stages of the cell cycle, respectively.


Protease effects on specific growth properties of normal and transformed baby hamster kidney cells. We have tested the effects of exogenous proteases on the growth of normal and transformed hamster fibroblasts in the classic culture assays for transformation. The results indicate that exogenous proteases act to decrease the serum requirement of normal cells but not nearly to the extent that occurs in the process of viral transformation. Proteases do not further decrease the serum requirement of transformed cells, nor do they affect the maximal saturation density or the plating efficiency in soft agar of either normal or transformed cells. Under conditions optimal for growth stimulation, proteases decrease the strength of cell-to-substrate adhesion but do not affect cellular morphology. In contrast to previous studies, experiments using highly purified trypsin and several different active-site inhibitors strongly suggest that the growth-stimulatory activity of trypsin is not directly related to the proteolytic activity of the molecule.


Mobility and distribution of a cell surface glycoprotein and its interaction with other membrane components. Fluorescence photobleaching recovery and immunofluorescence methods have been used to study the lateral mobility and topographical distribution of a major cell surface glycoprotein (CSP). Both endogenous CSP and fluorescent-labeled exogenous CSP bind to the cell surface in a fibrillar pattern and are immobile on the experimental time scale. Azide, vinblastine, and cytochalasin B do not alter the immobility and cell surface distribution of the CSP molecules. Therefore, oxidative phosphorylation and the cytoskeleton do not seem to be responsible for the properties of the bound glycoprotein. The presence of immobile CSP fibrils does not, however, impede the diffusion of a lipid probe, a ganglioside analogue, or various surface antigens. Therefore, the fibrils apparently do not form a "barrier" across the lipid phase of the plasma membrane. In contrast, concanavalin A binds to CSP and is largely immobile in regions rich in CSP. The presence of immobile concanavalin A receptors in areas or on cells lacking CSP indicates that other types of immobile concanavalin A receptors also exist.CSP does not bind to lipid bilayers composed of phosphatidylcholine or oxidized cholesterol. It does bind to dextran-coated bilayers as a diffuse distribution of mobile molecules that can patch after addition of antibodies to CSP. The latter result suggests that CSP molecules do not interact strongly with other CSP molecules under these conditions. Exogenous CSP binds to regions on the cell surface that already bear CSP. In view of the apparent weakness of CSP-CSP interactions on the lipid bilayer, it seems possible that the assembly of CSP fibrils is nucleated by cell surface components in addition to CSP.


Recombinant plasmid that carries part of the nitrogen fixation (nif) gene cluster of Klebsiella pneumoniae. We have cloned fragments of the Klebsiella pneumoniae genome that carry part of the his operon and part of the nitrogen fixation (nif) gene cluster on the amplifiable plasmid pMB9. One particular plasmid, pCRA37, complements mutations in the hisD, nifB, and nifF loci. The physical map of pCRA37 as determined by restriction enzyme analysis correlates with the genetic map of the his-nif region as determined previously by phage P1-mediated cotransductional analysis.


Mutants of Escherichia coli lacking in highly penicillin-sensitive D-alanine carboxypeptidase activity. Mutants of Escherichia coli lacking in the highly penicillin-sensitive enzyme activities of D-carboxy-peptidase, transpeptidase, and endopeptidase, and with the concomitant absence of penicillin-binding protein 4 of B.G. Spratt and A.B. Pardee [(1975) Nature 254, 516-517] were isolated. The defect of these mutants is ascribed to the lack of an enzyme, D-alanine carboxypeptidase Ib. Genetic mapping studies show the mutation (dacB) to be located at 68 min on the E. coli chromosome map. The dacB mutation results in the simultaneous loss of D-alanine carboxypeptidase and penicillin-binding protein 4. The mutants grew normally under a wide range of growth conditions. We conclude that the enzyme is not a necessary component for normal peptidoglycan biosynthesis in E. coli.


Simultaneous deletion of D-alanine carboxypeptidase IB-C and penicillin-binding component IV in a mutant of Escherichia coli K12. Mutants of Escherichia coli with much decreased activity of D-alanine carboxypeptidase (peptidyl-D alanine hydrolase, EC 3.4.12.11) were found among E. coli K12 extensively mutagenized with nitrosoguanidine treatment by assaying individual colonies for the enzyme activity. One such mutant with only 10-12% residual activity was characterized extensively. The soluble carboxypeptidase activity (corresponding to D-alanine carboxypeptidase IC of Tamura T., Imae, Y. & Strominger, J.L. [(1976) J. Biol. Chem. 251, 414-423] was deleted. This enzyme activity in the particulate fraction was markedly reduced but transpeptidase activity was normal. However, penicillin-binding component IV was deleted from the particulate fraction. Both the physiology and penicillin sensitivity of the organism were relatively normal, except that mutant cells were markedly more stable to penicillin-induced lysis, suggesting the possibility that carboxypeptidase IC really functions as an endopeptidase. The possible relationship of the deleted carboxypeptidase activity and the deleted penicillin binding component are discussed.


Rationale for combined use of fetal liver and thymus for immunological reconstitution in patients with variants of severe combined immunodeficiency. Bone marrow cells from a patient with severe combined immunodeficiency were studied in vitro for thymus-dependent lymphocyte (T cell) differentiation by using, at varying times, thymic epithelial monolayers and culture supernatants, thymopoietin, ubiquitin, and thymic extract as inducing agents. On initial evaluation, with thymopoietin or human thymic extract, only a partial differentiation of marrow cells was achieved into cells bearing the human T cell antigenicity without the capacity to form rosettes with sheep erythrocytes, suggesting that the stem cells were defective. Two fetal liver transplantations aimed at reconstitution were unsuccessful, despite evidence of chimerism. Induction studies at that time demonstrated rosetting capacity (with sheep erythrocytes) of the patient's bone marrow cells after coculture with thymic epithelial monolayers but not with their supernatants. An 18-week fetal thymus (irradiated) was then transplanted, but the transplantation was unsuccessful and no clear evidence of chimerism was demonstrated. Subsequently, transplantation of another fetal liver resulted in chimerism and immunologic reconstitution. Serum thymic factor activity rose from 1:2 before transplantation to 1:16 after reconstitution. The combined use of fetal thymus and liver may provide effective immunological reconstitution in some variants of severe combined immunodeficiency.


Immunohistochemical localization in rabbit brain of a peptide resembling the COOH-terminal octapeptide of cholecystokinin. Immunohistochemical techniques were used to demonstrate the presence of a material resembling the COOH-terminal octapeptide of cholecystokinin in rabbit cerebral cortical neurons. Deep staining was seen in cell bodies throughout the cortical grey matter and diffusely in the subcortical white matter.


Immunohistochemical analysis of peptide pathways possibly related to pain and analgesia: enkephalin and substance P. The distribution of Met-enkephalin- and substance P-immunoreactive neurons was studied by indirect immunofluorescence in some areas related to pain and analgesia. Met-enkephalin- and substance P-positive cell bodies and nerve terminals were observed in the periaqueductal central gray, the nucleus raphe magnus, the marginal layers and substantia gelatinosa of the spinal trigeminal nucleus, and the dorsal horn of the spinal cord. Lesion experiments suggest that Met-enkephalin neurons in the dorsal horn and possibly in the spinal trigeminal nucleus are interneurons or propriospinal neurons with nerve terminals in the laminae I and II of the cord and in the superficial layers of the spinal trigeminal nucleus, respectively. These areas are also very rich in substance P-positive nerve terminals, mainly representing central branches of primary afferent neurons. The present immunohistochemical-anatomical findings support the hypothesis that stimulation-produced analgesia is related to activation of spinal and spinal trigeminal enkephalin interneurons forming axo-axonic synapses with (substance P?) pain afferents in the superficial laminae of the dorsal horn and the spinal trigeminal nucleus. These interneurons may be activated by sensory fibers and by descending fibers from medullary stimulation sites. Transmitter substances in these descending fibers may be 5-hydroxytryptamine and substance P.


Serotonergic neurons in the peripheral nervous system: identification in gut by immunohistochemical localization of tryptophan hydroxylase. A specific antibody to tryptophan hydroxylase [L-tryptophan, tetrahydropteridine:oxygen oxidoreductase (5-hydroxylating), EC 1.14.16.4] has been used to localize the enzyme immunohistochemically in neurons of the mammalian gut. The enzyme was found in perikarya of intestinal neurons of mice, rats, and guinea pigs. Neurons containing the enzyme survived for up to 3 weeks in organotypic tissue culture and were intrinsic to the gut. These neurons are probably serotonergic and are the first such neurons to be found in the peripheral nervous system.


Cavernous sinus thrombosis revisited.

Cavernous sinus thrombosis revisited. In summary, cavernous sinus thrombosis is still with us. Patients now survive the disease more often than not, and therapy and diagnosis are reasonably clear cut. An increasing array of antibiotic-resistant bacteria have been balanced by an increasing army of antibiotics. The controversy over anticoagulation has not changed since reviewed by Parsons (1967). Ancillary measures remain more of value in diagnosis than in therapy. It is a disease primarily diagnosed by physical signs and symptoms, which requires prompt treatment. In our modern age of computerization and laboratory-based medical care, cavernous sinus thrombosis demands the diagnostic skill of the clinician, whose prompt ministrations should usually yield a favourable result.


Circling behavior in rodents following an imbalance of basal ganglia GABA concentrations. Unilateral focal injection of the GABA - transaminase inhibitor, ethanolamine O-sulphate, into one substantia nigra or globus pallidus of rats or the striatum of mice induces spontaneous and drug-induced circling behaviour. Circling parallels the imbalance of GABA concentrations between the injected and the noninjected side of the brain, being most striking on Day 1 and 3, and non-existent by Day 7. Increases in GABA concentration were demonstrated in areas distant from the injection site, on both the injected and noninjected side of the brain presumably due to diffusion of the ethanolamine O-sulphate. This diffusional effect made it impossible to define the exact site of GABA and dopamine interaction.


Simple and compact cannula system for mice. A small and simple device is described for applying substances to the brain of freely moving mice. The effectiveness of the technique was evaluated by intraventricular injections of d-amphetamine sulfate. It was observed that intraventricular injections of d-amphetamine (50-200 microgram) produced a dose dependent increase in activity.


The American Physical Therapy Association's code of ethics: its historical foundations. This paper surveys selected historical foundations of the present American Physical Therapy Association's CODE OF ETHICS, showing the extent to which the present code draws upon oaths, ideas in ethics textbooks, and other sources. The article presenta a basis for understanding the significance of these historical influences and provides one means by which physical therapists can more fully appreciate the relevance of the code today.


The management of stasis ulcers of the leg where the tendo calcaneus is exposed. Chronic leg ulcers may expose and destroy the tendo calcaneus, unless it can be covered soon. Current methods of management do not present a ready method. It is suggested that local muscle transpostion, with skin grafting over the muscle, is an effective form of treatment. An illustrative case is reported, and our clinical experience is presented.


Nipple-areola reconstruction with auricular tissues. Various methods of reconstructing the nipple-areolar complex with auricular tissues are presented. A basic one-stage reconstructive technique is described which seems suitable for the use of various tissues. An alternative method of correcting the inverted nipple is reported.


Use of vastus lateralis muscle flap for repair of trochanteric pressure sores. The use of a vastus lateralis muscle flap is suggested as an approach to the surgical repair of trochanteric pressure sores in paraplegic patients. The details of the anatomy of the muscle are outlined, and our surgical technique for its use is described.


Use of an innervated deltopectoral flap for intraoral reconstruction. The technique for the transfer of sensitive skin into the mouth for intraoral reconstruction is described. This procedure may be performed at one or two operative stages. Supraclavicular nerves supply sensation to the tip of the standard deltopectoral flap--which may be swung up with the nerves left in continuity, or the nerves may be divided and anastomosed to an appropriate sensory nerve in the mouth.


Simultaneous repair of the upper lip and nostril floor after tumor excisions. A lateral lip flap, with a perialar extension, is described for reconstruction of defects of the upper lip which extend into the columella and/or the nostril floor.


The effective duration of the delay phenomenon in the rat. In standard skin flaps in the rat, the effect of a delay was undetectable for the first 3 weeks and the maximum benefit was not apparent until the sixth week. At all time intervals the delay phenomenon was not as pronounced in the rat as in other species. The delay phenomenon in the rat lasts at least 30 weeks. The rat does not appear to be an ideal model for the study of skin flaps.


The use of a fascial flap in ear reconstruction. We describe the use of a fascial flap for covering the framework in ear reconstruction. When covered in turn with a skin graft, this fascial flap provides an abundant amount of a thin, tough, vascular, hairless cover of good quality in all cases except those where injuries in the auricular area have been deep enough to damage this fascia. This method of ear reconstruction is particularly useful in secondary ear reconstructions useful in secondary ear reconstructions and in reconstruction after traumatic losses. The procedure described can often be performed in one stage, requiring two to 4 hours, with minimal complications.


The adaptability of the glans flap in hypospadias repair. In severe cases of hypospadias where a multiple-stage repair has been selected, a more functional repair has been selected, a more functional and cosmetic result is possible, without an associated higher complication rate, if the glans flap is incorporated into the final stage of the repair.


The surgical treatment of necrobiosis lipoidica diabeticorum. We review the literature on the surgical treatment of necrobiosis lipoidica diabeticorum, and we describe 7 cases treated at Stanford University Medical Center. Experiences with them prompt us to recommend surgical excision of the lesions down to the deep fascia, ligation of the associated perforating blood vessels, and the use of split-skin grafts to cover the defects. There were no recurrences when we did all these things.


A simple method of total reconstruction of the penis. Case reports. We reconstructed the penis in two patients, using one testicle for bulk and framework with a silicone prosthesis being substituted for that testicle. The results, as far as appearance and relieving mental suffering are concerned, have been satisfactory. There is no sexual sensation, and the urethra remains in the perineum.


The biological effects and mode of action of L-canavanine, a structural analogue of L-arginine. Many of the 200 or so non-protein amino acids synthesized by higher plants are related structurally to the constituents of common proteins. L-Canavanine, the guanidinooxy structural analogue of L-arginine, is representative of this group. It has provided valuable insight into the biological effects and the mode of action of non-protein amino acids which acts as analogues of the protein amino acids. The arginyl-tRNA synthetases of numerous canavanine-free species charge canavanine, and canavanine is subsequently incorporated into the nascent polypeptide chain. Production of canavanine-containing proteins ultimately can disrupt critical reactions of RNA and DNA metabolism as well as protein synthesis. Canavanine also affects regulatory and catalytic reactions of arginine metabolism, arginine uptake, formation of structural components, and other cellular precesses. In these ways, canavanine alters essential biochemical reactions and becomes a potent antimetabolite of arginine in a wide spectrum of species. These deleterious properties of canavanine render it a highly toxic secondary plant constituent that probably functions as an allelochemic agent that deters the feeding activity of phytophagous insects and other herbivores.


Microcalorimetric investigations of the metabolism of yeasts. VI. Diauxy during anaerobic growth on different saccharides. The anaerobic growth of the yeast Saccharomyces cerevisiae with six different mono- and disaccharides as energy source was investigated calorimetrically. With mixtures of monosaccharides and disaccharides or disaccharides with each other, biphasic thermograms were obtained. The diauxic growth is discussed in view of constitutive and inducible transport systems and degradation enzymes.