A component analysis of attentional problems of educationally handicapped boys. Seventy-three educationally handicapped (EH) and 78 regular class, normally achieving (NA) boys grades 3-8 were tested with a series of measures selected to test three components of attention: coming to attention, decision making, and maintaining attention over time. EH and NA samples were subdivided into three gropus by grade level (grades 3-4, 5-6, and 7-8). Based on a teacher-completed behavioral check list, the EH group was further subdivided according to pupils perceived by teachers as hyperactive or nonhyperactive. With the exception of the youngest group, EH and NA samples did not differ from each other on CA, but regular class boys had slightly higher IQs and better reading scores than did their EH peers; EH hyperactives and EH nonhyperactives differed significantly on reading scores, the difference favoring the nonhyperactives. All pupils were individually administered the Children's Embedded Figures Test (CEFT), the Matching Familiar Figures Test (MFFT), and the Children's Checking Task (CCT), the last designed specifically to assess ability to maintain attention over time. EH pupils did not function as efficiently or as accurately on the attentional tasks as did their normally achieving age peers. Significant differences between EH and NA samples were found for CEFT and MFFT errors, as well as for CCT errors of omission and commission. Analyses of the EH group according to hyperactive--nonhyperactive status were for the most part nonsignificant. Correlational analyses yielded low but statistically significant relationships among the attentional measures, but nonsignificant relationships between IQ and the attentional test scores. Findings were consistent with the interpretation that the three hypothesized components of attention are partially independent and thus may have differential influence on pupils performance in school.


Attention and distractibility during reading in hyperactive boys. Nonhyperactive and clinically defined hyperactive boys were administered reading tasks under "quiet" and "distracting" conditions. Hyperactive boys were less attentive to task relevant stimuli and more attentive to task irrelevant stimuli than their controls. Our results demonstrate that the previous findings of inattentiveness among hyperactive boys on laboratory tasks can be generalized to more typical school activities such as reading.


Relative efficacy of methylphenidate and behavior modification in hyperkinetic children: an interim report. Children reported to be hyperactive in school and with behavior difficulties at home were randomly assigned to methylphenidate, behavior therapy and placebo, or behavior therapy with methylphenidate for an 8-week period. Rating scales were obtained from teachers and parents. Independent blind observers rated childrens' classroom bheavior on a weekly basis. A behavior therapy program was implemented in the home and at school. Methylphenidate dosage was individualized. Ratings of behavior deviance were significantly reduced by all treatments. However, a significant advantage for the groups receiving methylphenidate was found over the group receiving behavior therapy and placebo. No significant differences between methylphenidate alone and methylphenidate combined with behavior therapy were obtained. Global ratings of improvement done by teachers favored the combined treatment of behavior therapy and methylphenidate over behavior therapy and placebo. No differences among treatments were found in the mothers' global ratings of improvement. The results indicate that though all three treatments were effective, methylphenidate was significantly superior to behavior therapy alone.


Curvularin from penicillium baradicum Baghdadi NRRL 3754, and biological effects. Curvularin, a fungal metabolite similar in chemical structure to zearalenone, a potent estrogen, was tested for its estrogenic effects to gilts. No estrogenicity was observed to 60 kg gilts after feeding curvularin per os at a rate of 10 mg per day for 5 days. Curvularin was also nontoxic to mice and chick embryo.


Assessment of a cognitive training program for hyperactive children. Modeling, self-verbalization, and self-reinforcement techniques were used to train hyperactive children in more effective and less impulsive strategies for approaching cognitive tasks, academic problems, and social situations. Eighteen hyperactive children took part in the training program. The control group, which received no training, consisted of 11 children, matched with the experimental group on age, IQ, and measures of hyperactivity and impulsivity. Several tests and measures, some of which have been shown to differentiate between hyperactive and normal children, were administered prior to training at the end of the 3-month training period, and after a further 3-month period in which no training took place. The trained group showed significantly greater improvement on several of the measures, both at the time of posttesting and on the follow-up evaluation.


14C-Labeled aflatoxin B1 prepared with yeastlike cultures of Aspergillus parasiticus. A simple method was developed to produce 14C-labeled aflatoxin B1 by using the yeastlike phase of Aspergillus parasiticus NRRL 2999. Yeastlike cultures resulted from absence of manganese in a synthetic medium. Sodium acetate-1-14C had a 0.22% average incorporation; sodium acetate-1,2-14C, 0.70%. The average yield of labeled B1 was 10 mg/500 ml medium with an average specific activity of either 63.3 mCi/mole (C-1 label) or 194.3 mCi/mole (C-1, 2 label).


Residues of 2, 4-D in air samples from Saskatchewan: 1966-1975. Residues of 2,4-D (2,4-dichlorophenoxyacetic acid) in air samples from several sampling sites in central and southern Saskatchewan during the spraying seasons in the 1966-68 and 1970-75 periods were determined by gas-liquid chromatographic techniques. Initially, individual esters of 2,4-D were characterized by retention times and confirmed further by co-injection and dual column procedures. Since 1973, however, only total 2,4-D acid levels in air samples have been determined after esterification to the methyl ester and confirmed by gc/ms techniques whenever possible. Up to 50% of the daily samples collected during the spraying season at any of the locations and during any given year contained 2,4-D, with butyl esters being found most frequently. The daily 24-hr mean atmospheric concentrations of 2,4-D ranged from 0.01 to 1.22 mug/m3, 0.01 to 13.50 mug/m3, and 0.05 to 0.59 mug/m3 for the iso-propyl, mixed butyl and iso-octyl esters, respectively. Even when the samples were analysed for the total 2,4-D content, i.e. from 1973 onwards, the maximum level of the total acid reached only 23.14 mug/m3. In any given year and at any of the sampling sites, about 30% of the samples contained less than 0.01 mug/m3 of 2,4-D. In another 40% of the samples, the levels of 2,4-D ranged from 0.01 to 0.099 mug/m3. Only about 30% of the samples contained 2,4-D concentrations higher than 0.1 mug/m3, with only 10% or less exceeding 1 mug/m3. None of the samples, obtained with the high volume particulate sampler, showed any detectable levels of 2,4-D, indicating little or no transport of 2,4-D adsorbed on dust particles or as crystals of amine salts.


[Length of gestation and parameters of the menstrual cycle]. In studying the BBT curves of 433 conceptional cycles, no evidence was found of any correlation between duration of gestation counted from "zero" day, the last day of the hypothermic phase, and various parameters measuring durations or temperatures evaluated from the curves. There is, in particular, no positive correlation with the duration of the hypothermic phase; and the authors were able, by taking into account the error made in replacing ovulation by "zero" day, to deduce that the "true" duration of gestation is not correlated with the "true" length of the preovulatory phase or indeed with the length of the cycle.


[The action of the polypeptide placental hormones HCG and HCS on the blastic changes of lymphocytes in mixed cultures]. The present work studies the effect of the placental hormones HCG and HCS on cellular immunity in vitro. These two hormones used in identical or greater concentrations than found in circulating blood inhibit lymphoblastic changes in mixed cultures of lymphocytes. It is possible that HCG and HCS have the same inhibiting effect in vivo on immunity by cellular mediation in the pregnant woman. This inhibition could be of the greatest importance at the surface of the trophoblast where their concentration is probably raised, and where contact between fetal antigens and maternal blood also takes place.


[Histometric study of 55 cases of carcinoma in situ and microinvasive carcinoma of the cervix. Histogenetic deductions]. The authors present the results of a quantitative study of carcinoma-in-situ and occult invasive cancers of the cervix. 40 separate carcinomata in-situ were measured and the limits of their topography precisely defined with reference to the external os on the one hand and the "last gland" on the other. It is known that this gland is situated at the site of the original junction between the cylindrical and pavement epithelia. It confirms that carcinoma-in-situ always (with few exceptions) develops upwards from the area of the original junction between the cylindrical and pavement epithelia, and its topography is higher than that of dysplasia especially when the two types of lesion are associated.


[Thermography of the testicle. Preliminary study]. The preliminary study is concerned with 25 cases that have been examined using thermography in planes to check the conditions of temperature of the testes in normal and pathological states. Normal testicular thermography is characterised by a symmetrical and constant thermographic picture, the temperature staying between 32.5 and 34.5 degrees. In the pathological states of oligoasthenospermia plate thermography shows up a particular thermic picture associated with a varicocoele whether this is clinical or subclinical. The picture is one of hyperthermia and lack of symmetry in the case of a unilateral lesion. In these cases tyeing off the spermatic vein shows a rapid return to a normal thermographic picture. These positive results have led to a more extensive and deep study which is at present in progress.


[Occipito-posterior deliveries].

[Occipito-posterior deliveries]. The occipito-posterior position has been thought to be a presentation leading to dystocia as a result of faulty positioning of the head. Closer observation of the facts lead one to think that this kind of position is really the result of better accommodation of the fetal head to the shapes of pelvis to which one has not become used but which are normal: this means those where the antero-posterior diameters are greater. By itself the occipito-posterior position cannot give rise to true complications. It only needs a particular mechanism. In deliveries in the occipito-posterior position progress and prognosis depend less on the presentation than on the conditions, especially the anatomical conditions, which have given rise to or made more likely the position and which go with it. It is therefore these conditions that have to be recognized each time and taken note of in order to carry out the best possible treatment.


[The ovary after ovariotexy].

[The ovary after ovariotexy]. After reviewing the technique of the operation the authors report on the results of 25 cases of ovariotexy. This procedure of surrounding and placing the ovary extraperitoneally has been practised with the idea of performing a reversible sterilisation. Only 2 pregnancies resulted. 18 cases were reviewed after a certain interval of time (a mean of 2 1/2 years). 5 cases of dysmenorrhoea and 2 cases of cystic changes in the ovaries occured. 6 patients who before ovariotexy had regular cycles and were free of all symptoms and of all neuro-psychiatric treatment retained their regular cycles, controlled biologically. 6 further patients who had regular cycles but had a neuro-psychiatric history were seen of whom 4 kept to more or less regular cycles. The 6 patients who had irregular cycles did not change their cycles, but one only, who was 39 years of age, clinically and biologically produced the menopausal syndrome. The reversibility of the procedure has not been tested. Ovariotexy is not without risks, but these seem to be lessened when the operation is carried out on ovaries that are anatomically and functionally normal.


[Copper T 200 intrauterine device. Clinical study of 486 cases]. In this study on 486 T-Cu 200 placed in situ for an average of 12 months, analysis of results show that this Copper-I.U.D. has a complete efficacy and a very high continuation rate. The author establishes a relationship between these results and the selection of patients by hysterometry.


Localization of catecholamines in the eyes and other tissues of Aplysia. A green fluorescence indicative of catecholamines (CA) was localized in the secondary cells (nonreceptor neurons), neuropile and optic nerve of the eye and other tissues in Aplysia by using the formaldehyde-induced fluorescence method for the demonstration of biogenic amines. The specificity of the induced fluorescence was confirmed by its absence in tissue not exposed to formaldehyde vapor, relatively rapid decay upon exposure to UV light and its chemical reduction by sodium borohydride. The fluorescence was greatly reduced in eyes treated with reserpine (depletes serotonin and catecholamines). Furhter confirmation that the green fluorescence in the eye was due to a CA and not to serotonin was obtained by showing that it was decreased or eliminated by alpha-methyl-para-tyrosine (an inhibitor of catecholamine synthesis), increased by incubation in dopamine and exhibited a peak emission (470 nm) characteristic of CA fluroescence. CA fluorescence was also observed in the neuropiles of the cerebral, pedal, pleural and parieto-visceral ganglia and in cells in the pedal ganglion, statocyst, mantle, anterior tentacles and siphon. The finding of CA in secondary neurons of the eye was unusual since CA-containing cells have not been observed in other gastropod eyes. The distribution of CA in Aplysia, in tissue other than the eye, is similar to that of other gastropod molluscs.


Cytochemical localization of glycoconjugate in mitochondria. Complex carbohydrates and cations have been localized by cytochemical methods in mitochondria of mammalian leukocytes, hepatocytes and oyster gill epithelium. Glycoconjugate of acidic nature was visualized with the dialyzed iron method in or on the outer membrane and inner boundary membrane and in the outer intermembrane space but not on the membranes of cristae or in the intracristate space, or matrix. Sulfated glycoconjugate was demonstrated with the high iron diamine method in a similar distribution and in, on, or between, membranes of cristae as well. Intermittent aggregates of dialyzed iron and high iron diamine stained material were often found in the outer intermembrane space. The periphery of isolated rat liver mitochondria also stained with a Concanavalin A horseradish peroxidase technique, indicating the presence of macromolecules, presumably glycoproteins containing mannose or glucose. The distribution of antimonate reactive cation in mitochondria of leukocytes resembled that of the acidic glycoconjugate, indicating binding of cations to anionic groups of the latter. The complex carbohydrates and cations demonstrated cytochemically in mitochondria are considered in relation to previous biochemical studies.


The use of ferricyanide for the electron microscopic demonstration of dehydrogenases in human steroidogenic cells. The  ultrastructural localization of 3 beta hydroxysteroid ferricyanide reductase, glucose-6-phosphate ferricyanide reductase and nicotinamide adenine dinucleotide and reduced form-ferricyanide reductase was investigated in some human steroidogenic tissues (corpus luteum of pregnancy, fetal adrenal gland and testis, adult testis and placenta) using ferricyanide as an electron acceptor. Copper ferrocyanide deposits were readily observed in the mitochondria, in the smooth endoplasmic reticulum profiles and in the cytoplasm. The sites of the various dehydrogenase activities could be visualized by using appropriate incubating media. The precise localization of various reactions in different electron transfer chains was determined by using different ferricyanide concentrations and intermediate electron-carriers such as menadione or exogenous nicotinamide adenine dinucleotide and reduced form-diaphorase. The use of respiratory chain inhibitors such as rotenone or antimycine A confirmed these data.


Arterial hypotension induced by horseradish peroxidase in various rat strains. The influence of various commercial preparations of horseradish peroxidase upon the arterial pressure has been investigated using direct intra-arterial pressure recordings in Nembutal anesthetized rats of different strains. A marked hypotension was noted in Wistar and Sprague-Dawley rats when sufficiently high doses (5-10 mg/100 g body weight) were injected intravenously. This effect was observed with both highly purified (Sigma type VI, Boehringer Reinheitsgrad I) as well as less pure preparations (Sigma type II, Boehringer Reinheitsgrad II). Prior injection of promethazin, an antihistamine, prevented the drop in arterial pressure. Wistar/Furth rats appeared almost resistant to the hypotensive effect of Sigma preparations but developed moderate to marked hypotension with both types of Boehringer horseradish peroxidase. When instead of Nembutal, ether anesthesia was used only a transient mild hypotension developed and the animals recovered within 7-10 min. No effect was noted in Syrian hamsters receiving injections with the same doses of horseradish peroxidase. Electrophoresis revealed marked variations in the isozyme composition of different horseradish peroxidase preparations. Since the exact nature of the hypotensive agent remains unknown, it is suggested that the arterial pressure be monitored before extensive systematic application of this tracer in vascular permeability studies in rats.


Peroxisome development in the regenerating pars recta (P3 segment) of proximal tubules of the rat kidney. The development of peroxisomes, lysosomes and endocytic vacuoles in regenerating cells of the pars recta (P3 segment) of proximal tubules, in rats given a single interperitoneal injection of d-serine (80 mg/100 g.b.wt), was studied by light and electron microscopy using cytochemical methods. Rapid proliferation of cells occurred between 2 and 5 days after d-serine induced tubular necrosis; by day 6 almost all injured tubules were re-epithelialized with flat or low cuboidal cells. Peroxisomes and lysosomes were not observed during the period of rapid cell multiplication i.e., between 2 and 6 days after d-serine injection. Restitution of mitochondrial population preceded the development of peroxisomes in the newly regenerated cells of P3 tubules. Maximum development of peroxisomes occurred between 9 and 14 days after d-serine injection. The formation of peroxisomes appeared to correlate closely with the differentiation of apical endocytic vacuoles and the brush border. Lysosomes in the regenerated cells of P3 tubules were the last to develop.


[Quantitative studies on the dendritic spine distribution on the lamina-5 pyramidal cells in the anterior gyrus cinguli of the rat]. At three months old male rats the spine-distribution of the main dendrite and of the apical and basal dendrites of 36 lamina V-pyramidal cells of the regio cingularis (anterior cingulate cortex) was analyzed (from every subregion -- neocortex, mesoneocortex, mesoarchicortex -- 12 neurons). 1. The limbic pyramidal neurons show the same spine-distribution at their main dendrite as neocortical neurons of other brain regions and other mammal-species do: after an initial segment with poor spines only there follows an rapid increase of the spine-values with an amount at a range of 150 mum from the perikaryon, thereafter spine-values decrease continuously and slowly up the branching into the terminal bundle. 2. Basal and apical lateral dendrites however show another spine-distribution: basally there is an increase of the spine-values from the 1st up to the 3rd order, followed by a decrease at subsequent orders. Apically spine-density decreases from the 1st up to the 4th order. 3. The spine-distribution at the parts of the dendritic tree is discussed as a general biological sign of pyramidal cells. 4. The total number of spines of lamina V-pyramidal cells in the regio cingularis (anterior cingulate cortex) is less than those in the sensomotoric cortex and in the hippocampus, which corresponds with the lower differentiation of the limbic cortex. 5. By means of a variance-analysis the pyramidal spine-values of the three subregions were compared: concerning the total number of spines of a pyramidal neuron there are significant differences between the three subregions; the values are in the ratio of 3 to 2 to 1 (Regio praecentralis agranularis, 2461; mesoneocortex, 1664; mesoarchicortex, 800). The significantly least spine-density of all parts of the dendritic tree you can find in lamina V-pyramidal cells of the mesoarchicortex. 6. The equality of the basal and apical spine-values in the mesoneocortex is due to less specialization of these neurons. 7. The spine-values for a single dendritic field (EDF) show the differences between the limbic subregions clearly: there are significant differences between the three subregions concerning not only the number of spines but also the spine-densities apically and basally.


[Development of the isocortex of the human brain during the embryonic and fetal periods up to the 24th week of gestation]. From 98 specimens (Pr YAKOVLEV's Collection) we have been able to define the cytoarchitectonic criteria of the different stages of the development of the human Isocortex, and to stress some important features of the organogenesis of the human brain. Most of those findings are in agreement with G.I. POLIAKOV's publications on the cerebral development. Schematically it is possible to individualise three periods made of several stages: - The first one, from the 4th to the 6th week of Gestation during which the primitive neural epithelium, with its four layers (layers of His), is built up. - The second period, from the 7th to the 14th week, includes the two main tides of neuronal migration, separated by a period of recession. So, 4 cytoarchitectonic types of cortical plate may be described: type A. B. C. and D. - Thr third period is that of the stratification of the homogeneous Cortical Plate of type D, leading it through the patterns E I, II, III, IV to the stage of a six-layered Isocortex (24w). Beside this analytical description of the stages of development, the cytoarchitectonic criteria are able to give an ontogenetic evidence of the fundamental difference, already established by P. I. YAKOVLEV on neuropathological and neuroanatomical grounds, between the frontal, epipyriform Isocortex, and the caudal, epihippocampal Isocortex. During each of the stages described above, it is possible indeed to analyse specific features of one or the other part of the hemispheric wall and to determine a borderline between these two parts. Furthermore the temporal sequence of the events occurring inside the Isocortical Plate is slightly different in both parts, increasing the cytoarchitectonic contrast between them. In summary, such a study gives not only a precise definition of the ontogenetic stages of development of the Isocortex but also a better understanding of the organogenesis of the human brain, and by this way, it may be helpful in the analysis of the malformations of the Nervous System.


[Development of the neuronal structure of the hippocampus during pre- and post-natal ontogenesis in the albino rat. I. Neurohistological demonstration of the development of lung-axonal neurons in the CA3 and CA4 regions]. In this paper qualitative investigations by means of light microscopy (Golgi impregnation) considering the ontogenesis of efferent neurons of the CA3, CA4a, CA4b regions in the rat hippocampus are presented following the already described development of CA1 pyramids (MINKWITZ and HOLZ 1975). After the migration of neuroblasts the types of projective neurons can be distinguished in the mentioned regions at the end of the prenatal period. During the first postnatal time particularly the basal dendritic tree develops expressing more distinctly the typical forms of pyramids (CA3, CA4a) and the of the multipolare neurons of CA4b. No distinct qualitative jumps at the transition of the regions in contrast to the CA3--CA1 boundary can be observed. Temporal retardations in the appearance of postsynaptic structures (microdendrites, excrescenses, spines) at pyramidal neurons from CA4 to CA3 and CA1 are regarded as signs of earlier development of the phylogenetic older pool of cells. During the early postnatal developmental period (until stage P10) proceedings of the growth are predominant. Later on, during the late postnatal period, the maturation of the neurons takes place with a considerable multiplication of spines distributed in similar ways as known from other pyramids. At stage P20 neurons of all hippocampal regions cannot be distinguished from adult ones without using morphometric procedures. The development of parts of the intrahippocampal network including mossy fibre system and SCHAFFER collaterals is discussed with regard to in this way appearing boundaries between fascia dentata and regio inferior CA4, CA3) and regio superior (CA1). These fibre systems establish by their stepwise construction one of the basic elements to hippocampal functioning.


[Development of neuronal structure in the hippocampus during pre- and post-natal ontogenesis in the albino rat. II. Neurohistological demonstration of the development of interneurons and of the relationship between long- and short-axonal neurons]. In this paper qualitative results are presented from GOLGI preparations by light microscopic evaluation about the appearance and the ontogenetic changes on GOLGI-II-type neurons of the rat hippocampus from 15 stages of age between the 20th embryonic and the 20th postnatal day. Interneurons are already detectable in all the hippocampal regions in the prenatal period. Their postnatal growth expresses above all in lengthening rather than in multiplication of the amount of dendrites. Cells predetermined for developing spines show already early in the postnatal period a rather large amount of spines. The further multiplication of the spine density remains minimal that never values of adult pyramids will be reached. The form of the dendritic and axonic fields of neurons with short axons is very variable. Nevertheless three main categories of GOLGI-II-type neurons can be distinguished: 1. neurons, the axonic and dendritic ramifications of which strongly remain within the layer (do not exist within the stratum pyramidale), 2. neurons, which are able to contact afferent fibres in other layers by means of ascending and/or descending dendrites, 3. basket cells, the axons of which have direct influence on the perikarya of pyramidal neurons. Within the region CA4b interneurons of the 2nd group could be found, dendrites of which penetrate into layers of the fascia dentata. Such a fact does not exist at the multipolare, efferent neurons of the same region and could never be seen at any axonic ramification. In the presented paper aspects of influencing the maturation of pyramides by interneurons are discussed. Also has been tried to summarize the results about the neuronal structure of the rat hippocampus by schemes of frontal sections from four selected stages of age.


[Development of neuronal structure in the hippocampus during pre- and post-natal ontogenesis in the albino rat. III. Morphometric determination of ontogenetic changes in dendrite structure and spine distribution on pyramidal neurons (CA1) of the hippocampus]. Following GOLGI impregnation pyramidal neurons of the rat hippocampus (CA1) from four stages of age (E21, P5, P10, P20) were investigated by morphometric methods with regard to their dendritic structure and amount and distribution of spines. The daesults show, that during the ontogenesis until reaching adult values the determined parameters are strongly following in their expression the sequence: degree of ramification, length of dendrites, amount of spines, and in the development of the certain dendritic parts of the pyramid the sequence: main apical dendrite with end ramifications, basal dendrites, apical lateral dendrites. Along the main apical dendrite the pattern of spine distribution develops proceeding from the form of a reverse nearly plain parabola (P5, P10) to the curve known from other adult pyramides (P20) with a spine poor initial segment, then the rapid increase in the number of spines (maximum of spine density in the middle of the whole distance), followed by a subsequent slow decrease in the number of spines. The apical end ramifications are mostly developed in the degree of ramification and length of dendrites during the prenatal period and show postnatal only significant changes in the spine density without reaching the values of the other dendritic fields. At basal dendrites no further increase in the number of dendrites can be found after P10. In dendritic length and spine density they are reaching adult level about the 20th postnatal day. In comparison with that, apical lateral dendrites show at P20 their definitive amount and a further increase of the spine density must be expected. The single dendritic fields of apical lateral dendrites are in length and total amount of spines sometimes smaller than those of basal dendrites, but more abundant. In both cases the spine densities increase until the stage P20 but they are not differing. Caused by the further development of apical lateral dendrites to adultness a predominance of the spine density of this part of the neuron is known. The total length of the dendrites of one pyramidal neuron (CA1) increases from 1000 mum (E21) to 5600 mum (P20), while the total amount of visible spines and the spine density increase from 20 to 3000 spines resp. from 0,02 to 0,55 spines/mum. It is important that the portion of the apical lateral dendrites grows from 2 to 40%, the portion of basal dendrites only from 20 to 33%, while the importance of the apical end ramifications decreases from 60 to 20%. In the presented paper the comparisons of developmental stages of the most pyramidalized hippocampal neurons (CA1) with adult pyramids of this region and with cortical pyramidal neurons of different phylogenetic ages are discussed.


The ultrastructure of astroglia of the corpus callosum during ontogenesis. An Ultrastructural study of morphological events occurring in the astroglia of the corpus callosum during postembryonal ontogenesis has been undertaken. The results of investigation have shown that in the rat corpus callosum, as early as 1 day postnatal, there may be distinguished two different types of glial cells, which during further maturation develop into protoplasmatic and fibrillar astrocytes. From the observations made it would appear that maturation of the astroglia is a continuous process and no sharp morphological borderlines can be drawn between the astrocytoblast and the astrocyte. However, it has been found that maturation of astrocytes in the rat corpus callosum is completed at the age of between 28 and 40 days postnatal.


Activation of the complement attack mechanism in the fluid phase and its control by C567-INH: lysis of normal erythrocytes initiated by zymosan, endotoxin, and immune complexes. Addition of zymosan-serum complexes to guinea pig erythrocytes in guinea pig complement-EDTA was found to result in substantial lysis of the bystander cells in the presence of polycations such as poly-L-lysine of 178,000 daltons. Involvement of the alternative C pathway was shown, and the optimum time, temperature, and eruthrocyte and polycation concentrations were defined; a surprising efficiency was observed at low temperature and high cell concentrations. Several lines of evidence indicated that this hemolysis was mediated via the C567 complex of the C system and modulated by serum inhibitors of C567 (C567-INH): lysis was observed only with zymosan-serum complexes possessing C-consuming activity; it was not observed in C5-depleted guinea pig serum but was restored upon addition of purified C5; the addition of partially purified C567-INH insubstantially depressed hemolysis; and poly-L-lysine which is known to neutralize C567-INH in solution resulted in substantial enhancement of hemolysis. We also sought to determine whether the addition of complement activators directly to erythrocyte-serum mixtures could result in the hemolysis of bystander erythrocytes. It was found that zymosan, endotoxin, antigen-antibody complexes, and aggregated human gamma-globulin each could initiate such bystander lysis under appropriate conditions. Lysis again was favored by increased erythrocyte concentrations, low temperatures, and the presence of polycations such as poly-L-lysine, and was found to be mediated via the C system. C567-INH blocked cytolysis whereas poly-L-lysine potentiated hemolysis by neutralization of C567-INH. These experiments emphasize the propensity for C567 formation and lysis of bystander erythrocytes during C activation generally, the role of C567-INH in the control of this lysis, and the susceptibility of these interactions to modulation by highly charged macromolecules.


Interaction of K lymphocytes with myeloma proteins of different IgG subclasses. Human myeloma proteins of the four IgG subclasses and their Fc, F(ab)2, and Fab fragments were tested for their ability to inhibit antibody-dependent human K lymphocyte-mediated cytotoxicity to chicken erythrocytes (CRBC) sensitized with specific rabbit antibodies. In addition, the adsorption of K cells onto glass bead columns coated with myeloma proteins was investigated. Myeloma proteins and their Fc fragments of all four subclasses inhibited K cell activity. However, there were wide variations within a given subclass and IgG2 and IgG4 proteins usually inhibited less than IgG1 and IgG3 proteins. Aggregation of the weakly inhibitory proteins with bis-diazotized benzidine increased their inhibitory effect. An IgG1 half-molecule with a deletion in the Cgamma3 domain was weakly inhibitory. Passage of lymphocytes through glass bead columns coated with IgG1 and IgG3 proteins removed K cell activity. In contrast, columns coated with IgG2 and IgG4 proteins, even when aggregated with BDB, failed to absorb K cells but removed significant numbers of SIg positive B lymphocytes. An enhancement of the antibody-dependent cytotoxicity was observed in 34% of the inhibition experiments in the presence of low concentrations of the weakly inhibitory proteins, usually IgG2 and IgG4. This enhancement occurred more frequently (53% of the experiments) with Fc fragments independent of the subclass. Moreover, addition of IgG2 and IgG4 but not IgG1 and IgC3 fragments induced a dose-dependent cytotoxicity to CRBC in the absence of anti-CRBC antibodies. These data indicate that IgG2 and IgG4 proteins have a lower affinity to K cells than IgG1 and IgG3 proteins and are compatible with an earlier hypothesis that proposes that more than one site on the Fc fragment can react with Fc receptors. The present results suggest in addition that there may be functionally different sites, one having a triggering function in K lymphocyte lysis that may be localized on the second constant domain and one being responsible for high affinity binding of IgG to cell receptors that is probably localized on the third constant domain.


Investigations of the complement-fixing sites of immunoglobulins. Indirect evidence for the complement-fixing site of human IgG1 has been found by using chemical modification of the immunoglobulin. These results implicate the amino acid residues, tryptophan, tyrosine, and arginine. Furthermore, by the use of synthetic peptides it has been shown that the area surrounding the tryptophan and tyrosine at positions 277 and 278 probably constitutes the locus of the complement-fixing site of human IgG1. By analogy, the tryptophan at position 488 of human IgM is implicated in the complement-fixing site of this immunoglobulin. Evidence for this is presented by a peptide which mimics the sequence 487-491 of human IgM and possesses the ability to consume complement. The relative complement-fixing ability of this peptide is 200 times less effective than human IgG1.


Serotonin-induced production of a monocyte chemotactic factor by human peripheral blood leukocytes. Serotonin and histamine are released during the early phase of inflammatory reactions. To determine if these vasoactive amines might play a role in the cell-mediated phase of inflammation, studies were undertaken to assess their influence on some immunologic functions of human peripheral blood leukocytes (PBL). PBL were cultured with serotonin or histamine, and assayed for a proliferative response and their cell-free supernatants were assayed for the presence of a mediator with chemotactic activity for monocytes. Neither serotonin nor histamine were directly chemotactic for monocytes. When serotonin was cultured with PBL factors chemotactic for monocytes as well as polymorphonuclear leukocytes were produced in the absence of a proliferative response. Production of the factor chemotactic for monocytes was specifically blocked by methysergide, a serotonin antagonist and nonspecifically blocked by cycloheximide which interferes with leukocyte protein synthesis. Some dearboxylated precursors of serotonin also induced the monocyte chemotactic factor. This serotonin-induced chemotactic factor was demonstrated to be a product of mononuclear cells, and the majority of chemotactic activity was physiochemically similar to the previously characterized lymphocyte-derived chemotactic factor, suggesting that this factor is a lymphocyte product. In contrast to serotonin, histamine did not stimulate the production of monocyte chemotactic factor, nor did it induce proliferation. However, when 10(-5) M histamine was added to a substimulatory concentration of serotonin (10(-5) M), chemotactic activity comparable to or greater than the peak activity of serotonin alone was measured. This synergistic effect between serotonin and histamine suggests that the combination of these two amines may contribute to the induction of monocyte exudation in inflammatory reactions.


Disparity of IgE binding between normal and tumor mouse mast cells. The binding constants of rat and mouse IgE to normal and neoplastic rat and mouse mast cells have been measured. None of the cells distinguishes between rat and mouse IgE. Rat normal and neoplastic mast cells and mouse mastocytoma cells show very similar binding properties: k1 approximately 10(5), k-1 approximately 10(-5) and, therefore, KA approximately 10(10). Normal mouse mast cells also show a forward rate constant, k1, of 10(5) but the dissociation rate constant, k-1, is 50 times higher (5 X 10(-4)). The detergent-solubilized receptors reflect the properties of the cell-bound receptors. The discrepancy in binding by normal and neoplastic mouse mast cells remains unexplained but appears to be a reproducible finding for the cells from three strains of normal mice and three different mastocytomas studied.


Relationship of functional levels of early components of complement to the H-2 complex of mice. The relationship between the H-2 complex and the complement system was studied by performing functional assays for whole complement and individual complement components on sera from congenic mice of B10 and C3H backgrounds. Levels of whole complement activity were seen to be influenced by S region genes, confirming the work of others. Levels of C3 through C9, however, were independent of the H-I genotypes suggesting that the differences in whole complement activities were due to variation in levels of C1, C4 or C2. Titrations of these three earliest acting classical complement components were performed on sera from mice of nine strains of the B10 background and four strains of the C3H background. It was shown that functional levels of C1, C4, and C2 were all under control of genes within or very closely linked to the S region.


Analysis of the cross-reactive immune suppression induced by the random copolymers L-glutamic acid50-L-tyrosine50 (GT), L-glutamic acid60-L-alanine40 and L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT). Cross-reactivity in the induction of immune suppression by the structurally related polymers of L-glutamic acid, L-alanine, and/or L-tyrosine (GAT, GA, GT) was studied. SJL (H-2S) and DBA/1 (H-2q) mice are nonresponders to GAT and GT, whereas SJL, but not DBA/1 responds to GA. Both strains respond to these polymers when complexed to the immunogenic carrier methylated bovine serum albumin (MBSA). Preimmunization with GA suppresses GA-MBSA as well as GAT-MBSA and GT-MBSA plaque-forming cell (PFC) responses in DBA/1 mice. Likewise, GAT suppresses GAT-MBSA and GA (SJL) and GA-MBSA (DBA/1) PFC responses in both strains while being totally ineffective on GT-MBSA responses. GT preimmunization suppressed GA, GAT-MBSA, and GT-MBSA PFC responses in SJL but not DBA/1 responses. This study demonstrates that cross-reactive immune suppression does not follow predictable patterns based upon cross-reactivity of specific antibodies and that cross-suppression is not reciprocal.


REgulation of the primary immune response in vivo by parathyroid hormone. Injection of sheep red blood cells into rats stimulates splenic DNA synthesis, then increases the proportion of plaque-forming cells, and finally raises the circulating antibody level. Removal of the parathyroid glands, which causes hypocalcemia, 24 hr before antigen injection impairs all of these responses, but is without effect after antigen injection. It is suggested that parathyroid hormone and calcium control the immune response, probably by affecting the proliferative phase of this response.


Synergism between immune complexes and serum from tumor-bearing mice in the suppression of mitogen responses. Immune complexes either adhering to the cells, or added to cultures, synergized with an inhibitor present in serum to suppress the proliferative response of lymphocytes to specific antigens or to B cell or T cell mitogens. The suppressive effect was dependent on the concentration of both the complex and the serum and was substantially higher when the serum was taken from tumor-bearing, rather than normal mice. Immune complexes alone were not suppressive, but appeared to activate or increase the effectiveness of an inhibitor present in serum. Complexes of syngeneic mouse serum or specifically purified rabbit or sheep antibody, as well as heat aggregated mouse or rabbit Ig, were all effective, whereas heat-aggregated F(ab')2 fragments of rabbit Ig were not, suggesting that any aggregate hearing exposed Fc fragments could mediate synergy. Purified T lymphocytes were equally as sensitive to inhibition as the whole spleen cell population, implying that the suppression acted directly on responding cells rather than via an accessory cell.


Immunogenicity of FaB fragment of protein-315 for BALB/cmice. Immunogenicity of Protein-315 and its Fab fragment (Fab-315) for isologous and heterologous strains of mice was investigated by comparing the characteristics of the anti-idiotypic response produced in BALB/c and A/J mice. The ability of these anti-idiotypic antisera to compete with DNP-lys for the ligand-binding site of Protein-315 were analyzed by comparing their hapten inhibition curves. The anti-idiotypic responses of BALB/c mice to Protein-315 and to Fab-315 were similar to one another with regard to antibody specificity and sensitivity to inhibition by hapten, suggesting that both forms were equally immunogenic in inbred BALB/c mice. This observation indicates that the Fc portion of Protein-315 is not essential for the induction of anti-idiotypic response. Both BALB/c and A/J mice recognized the same antigenic determinants on Fab-315 since the anti-idiotypic antibodies produced by these animals were indistinguishable with regard to their interaction with Protein-315, Fv-315, and sensitivity to hapten inhibition. On the other hand, the response of A/J mice to Protein-315 was remarkably different from that of BALB/c mice since it was found that Protein-315 seemed to be more immunogenic in A/J mice than in BALB/c mice. The data also indicated that Protein-315 was more immunogenic than Fab-315 in stimulating the anti-idiotypic response in A/J mice. A/J antiserum to Protein-315 was found to have antibodies specific for the ligand-binding site as well as those specific for other antigenic determinations on the Fc portion. These findings suggest that the Fc portion of Protein-315 may either act as a haptenic determinatant to provoke directly the antibody response or as a carrier determinant to enhance the anti-Fab response in A/J mice.


Chemotaxis of human polymorphonuclear neutrophils under agarose: morphologic changes associated with the chemotactic response. Studies of morphologic changes of leukocytes responding to a chemotaxin gradient have been limited due, in part, to difficulties encountered with detailed electron microscopic analysis of cells migrating through membrane filters or on glass slides. The recently developed migration under agarose method provides a new opportunity to view and compare morphologies of cells migrating spontaneously and in response to a chemotaxin gradient. The present report describes the morphologic features we have observed by scanning electron microscopy of human polymorphonuclear leukocytes both spreading on a cover slip and migrating under agarose. We demonstrate that cells migrating under agarose exhibit a morphology that differs distinctly from that of cells spreading on a cover slip and, further, that the cytoplasmic periphery of cells responding to a chemotactic gradient under agarose becomes very irregular due to the formation of blebs or small pseudopodium-like structures.


Partial characterization of human C5a anaphylatoxin. I. Chemical description of the carbohydrate and polypeptide prtions of human C5a. Human C5a was isolated from complement-activated serum and was characterized for protein and carbohydrate content. The purified C5a was judged to be homogeneous by both polyacrylamide gel electrophoresis and immunologic techniques. The polypeptide moiety of C5a contains 73 amino acid residues which represent a m.w. of 8,200. Analysis of the carbohydrate moiety in C5a indicated 4 moles of glucosamine, 3 to 4 moles os sialic acid, 4 moles of mannose and 2 moles of galactose. The total carbohydrate content in C5a, therefore, amounts to approximately 25% of the apparent m.w. of the anaphylatoxin molecule. The protein and carbohydrate portions of C5a together equal a m.w. of approximately 11,000 which is considerably less than the 15 to 16,000 indicated by physical measurements. Human C5a contains a COOH-terminal arginine which is essential for anaphylatoxin activity and a sequence of Gln-Leu-Gly-Arg-COOH at the COOH-terminus which compares favorably with that of human C3a (Gly-Leu-Ala-Arg-COOH). Additional similarities between the C3a and C5a molecules include length of the polypeptide chain, number of disulfide bonds and an absence of tryptophan residues. A major chemical difference does exist between these two human anaphylatoxins, namely that carbohydrate is associated with C5a but is absent in the C3a molecule. The partial NH2-terminal sequence of C5a was determined as NH2-Thr-Leu-Glx-Lys-Ile-Glx-Glx-Ile-Ala- and direct comparison with the known sequence of human C3a shows little homology.


Hapten-sandwich labeling. III. Bifunctional reagents for immunospecific labeling of cell surface antigens. Bifunctional reagents have been prepared which permit extensive coupling of haptens to antibodies with retention of antibody-binding capacity. This modification procedure increases the sensitivity with which cell-surface antigens can be labeled for fluorescent or electron microscopy by the hapten-sandwich method to a level comparable to or greater than may usually be achieved by conventional indirect techniques. With two different haptens, and amplifying with anti-hapten antibodies bearing fluorescent or other markers, different antigens can be distinguished readily on a single cell or on separate cells. Mouse alloantigens detected only with difficulty by conventional fluorescence can be discerned clearly and with high specificity. The reagent, either methyl hydroxybenzimidate (HB) or methyl 3,5-dihydroxybenzimidate (DHB), is first reacted with a diazonium phenyl hapten. Since the resulting azo-derivative retains the imido ester function, the reaction solution can be used directly to amidinate antibodies. Both HB and DHB are easily prepared and may be stored for use as needed. With these reagents, the hapten-sandwich procedure may be applied to proteins other than immunoglobulins, e.g., hormones and mitogens. In addition to labeling antigens for fluorescent or electron microscopy, haptenamidinated antibodies or other ligands may be used in conjunction with appropriately modified antihapten amplifiers for a variety of purposes in cell biology, such as radioisotope studies, selective cell killing or suppression, and isolation of membrane antigens.


The inhibition of initial steps of lymphocyte transformation by cytochalasin B1. CB was shown to inhibit the PHA-induced activation of rabbit lymph node lymphocytes as assessed by the incorporation of 3H-uridine into RNA or 3H-thymidine into DNA. This suppression was dose dependent with an optimum of 10 mug CB/ml (20, 8 muM). Mitogen-activated lymphocytes escaped the inhibitory effect of the drug when CB was added later than 1 hr after the addition of PHA. CB also suppressed the activation of membrane phospholipid metabolism which occurs among the earliest detectable changes in activated lymphocytes. Thus the incorporation of 14C-choline, 14C-acetate, or 14C-oleate into lecithin in the presence of PHA and CB was the same as the level of their incorporation in unstimulated lymphocytes. The increased incorporation of 14C-oleate into lecithin of the plasma membrane of activated lymphocytes was similarly prevented in the presence of CB. In contrast, CB exhibited no or only a marginal effect on the phospholipid turnover of unstimulated lymphocytes. Our results point to plasma membrane phospholipid metabolism as the possible site of CB interference with the lymphocyte activation.


Carrier-dependent selectin of antibody clones and classes during the immune response. The selection of antibody clones and antibody classes during the immune response to the hapten oligo-D-alanine was found to be carrier dependent. When the hapten was coupled to a T-independent antigen (streptococci) a restricted immune response of IgM and IgG antibodies was induced. When the hapten was coupled to a T-dependent antigen (ovalbumin) a heterogenous response of only IgG antibodies was found. The carrier had an effect on the affinity of IgG but not of IgM antibodies. Clonal pattern and class distribution were fixed early in the immune response. Second and third immunizations with a heterologous carrier elicited the same clonal pattern and class distribution in the secondary response as that found with the original carrier.


Automated complement fixation test for the detection of antibodies against the core of hepatitis B virus (HBc). The automated complement fixation system presented in this paper differs from those described by Studievic et al. (1971) and Vargues and Henley (1974). In the one developed here only one sampler is used with a wheel presenting a double row of cups. This system can assay 60 samples per h and can be modified to double this number. Our unit requires an incubation period of 15 min at 37 degrees C and we have nerver observed any contamination of the samples during the assay run.


A bioassay employing polyethylene glycol for measuring neutralization of interferon by specific antibodies. A bioassay employing polyethylene glycol (PEG) for measuring the level of interferon-neutralizing antibodies is described. The method is based on incubating a concentrated preparation of interferon with an appropriately diluted anti-interferon serum or globulin for 1 h at 37 degrees C, precipitating the antigen-antibody complexes as well as some free serum protein with sterile PEG at a final concentration of 10% for 18 h at 4 degrees C, separating the sediment by centrifugation, and titrating the residual interferon in the supernate. It is not necessary to remove PEG from the samples since it is not toxic for tissue culture at a final concentration of less than 1%.


The detection of cytoplasmic immunoglobulins by immunofluorescence: improvements in techniques and standardization procedures. Iprovements in the technique of cytoplasmic immunofluorescence on cytocentrifuge slides obtained from cells in suspension are described. Refinement and standardization of the technique enabled us to obtain representative samples from the tissues under study and to determine the relative distribution of cells containing different heavy and light chain Ig determinants, as well as the absolute numbers of Ig-containing cells. The reproducibility of the results was highly satisfactory.


Effect of sulfones on complement deposition in dermatitis herpetiformis and on complement-mediated guinea-pig reactions. The role of complement and the mechanism of sulfone action in dermatitis herpetiformis (DH) have not yet been established; prior studies have presented conflicting data regarding the effect of sulfones on complement activation and deposition. Thirty-eight DH patients were studied. Twenty-four of 25 perilesional skin biopsies and 50 of 67 normal-appearing skin biopsies showed the third component of complement (C3) deposited in areas corresponding to those of IgA deposition. Nine of 10 patients with bound C3 in normal-appearing and perilesional skin during periods of active disease continued to have C3 in normal-appearing skin when treatment with sulfones kept them completely free of lesions for 2 to 8 weeks. When either Hartley-strain or C4-deficient guinea pigs were given up to 150 mg/kg sulfoxone (a water-soluble sulfone) intraperitoneally for 8 days before elicitation of active Arthus, reverse passive Arthrus reactions, or Forssman shock, there was no difference in time course, character, or intensity of reactions when compared to saline-treated control animals. We were therefore unable to demonstrate any effect of sulfones on complement deposition in DH skin or on complement activation in classical or alternate complement pathway-mediated guinea-pig reactions.


In vitro anaphylaxis in guinea-pig skin: amplification by burimamide. The effects of burimamide, an H2-antihistamine, on the anaphylactic reaction in the skin of ovalbumin-sensitized guinea pigs were studied in vitro. Burimamide enhanced the concentration of histamine in the supernatant fraction of antigen-challenged sensitized guinea-pig skin in a dose-related way, but did not alter the concentration of residual histamine in the skin after antigen challenge. The enhanced histamine concentration in the supernatant was not due to increased histamine synthesis by the target cells during the reaction because the increase was not inhibited by a histidine decarboxylase inhibitor, Brocresine. In further experiments it was shown that guinea-pig skin possesses potent histamine degrading enzyme activity which is inhibited by burimamide. We suggest that inhibition of these degrading enzymes leads to the increase in histamine concentration in the presence of burimamide.


A quantitative dermatophyte infection model in the guinea pig--a parallel to the quantitated human infection model. A method is described for inducing quantitative dermatophyte infections in guinea pigs. This model is unique in that the epidermis in the infection site is not traumatized nor is it epilated. One hundred spore-inocula of Trichophyton mentagrophytes var. granulosum ATCC number 18748 induced infections in 85% of tested guinea pigs. The course of these infections in guinea pigs that had not had a previous infection (inexperienced) and those that had (experienced) paralleled that seen in experimental infections of human volunteers.


Unbalanced RNA accumulation in regenerating mouse epidermis following abrasion. Following removal of the epidermis from the backs of CD-1 female mice, the epidermis is regenerated from the underlying resting hair follicles. The epidermis, which is normally 2 cell layers in thickness, reaches 7 cell layers by 5 days after abrasion and maintains this thickness throughout the rest of the 7-day experimental period. DNA and protein accumulate coordinately with the increase in epidermal wet weight as the regenerating epidermis thickens, reaching 3 to 4X normal levels by day 5. In contrast, RNA accumulates disproportionately, reaching levels over 12X that of normal by day 5. The unbalanced accumulation of RNA is also seen per cell since there is a 3- to 4-fold increase in the RNA/DNA ratio as well as approximately comparable increase in RNA/protein. Protein/DNA does not increase markedly during regeneration, although at days 6 and 7 it does increase slightly.


Black light induction of skin tumors in mice. Albino inbred mice (A/J strain exposed to 40-w black light fluorescent lamps (BLB) for 12 hr a day for up to a year developed inflammatory and hyperplastic responses on hairless ear and tail skin, but not on back skin covered by hair. After 1 year of such exposure, many individuals developed papillomas, carcinomas, and sarcomas on their ears and tails. It may be concluded that black light is a skin carcinogen for A/J mice.


51Chromium-release microassay technique for cell-mediated immunity to mumps virus: correlation with humoral and delayed-type skin hypersensitivity responses. Lymphocyte-mediated immune responsiveness to mumps virus was studied with use of a 51chromium (51Cr)-release microassay of lymphocytotoxicity to target cells persistently infected with mumps virus. The release of 51Cr from immune cells was found to be virus-specific and reproducible and correlated well with the presence of antibody but not with the magnitude of antibody levels. Delayed-type skin hypersensitivity and specific immune release of 51Cr did not correlate well, which suggests that the two events may be mediated by different populations of cells.


Transmission of hepatitis B associated with hemodialysis: role of malfunction (blood leaks) in dialysis machines. In the first 10 months of 1974, 26 of 60 susceptible patients in a commercial hemodialysis unit developed asymptomatic infection with hepatitis B virus; 17 (65%) of the 26 cases occurred in 14 weeks from July to October. In a case-control study, 15 of 16 cases for whom records were available were found to be associated with malfunctions of dialysis machines (primarily leaks or ruptures in dialysis membranes) that had occurred before patients converted to hepatitis B surface antigen (HBs Ag) positivity. In comparison, 17 of 34 controls were associated with machine malfunctions (P less than 0.01). In addition, the mean number of malfunctions in machines per patient was significantly greater for cases of infection (2.25 +/- 1.34) than for controls (1.06 +/- 1.39) (P less than 0.01). Furthermore, a direct correlation was demonstrated between an increase in blood leaks in machines used with susceptible patients and subsequent increases in cases of hepatitis for the various beds in the unit (r=0.994, P less than 0.0001). The mean period from the last blood leak to HBs Ag seroconversion was 67 days. Six of the 36 blood leaks associated with cases of infection occurred less than 6 hr after leaks in the contaminated area, whereas only one of 36 leaks associated with controls demonstrated this relationship (P less than 0.05). These data suggest that the conversion to HBs Ag positivity was linked to the occurrence of machine malfunctions (blood leaks) and that events which occurred during these episodes caused the spread of infection.


Temperature-sensitive mutants of influenza A virus. XI. Transfer of ts lesions in the Hong Kong/68-ts-1 [a] virus to the influenza A/Udorn/72 wild type. The presence of the temperature-sensitive (ts) lesions of complementation-recombination groups 1 and 5 in the Hong Kong/68-ts-1[A] virus was confirmed by genetic analysis of ts recombinants of the Hong Kong/68-ts-1[A] virus and a Udorn/72 wild-type virus. Three classes of Udorn/72-ts recombinants were found. One class possessed both ts genes of the Hong Kong/68-ts-1[A] parent, a second class possessed the ts lesion characteristic of group 1, and a third class possessed the ts lesion of group 5. The Hong Kong/68-ts-1[A] parent and the Udorn/72-ts recombinants exhibited a 10,000-fold or greater restriction of replication in the lungs of hamsters than did the homologous wild-type virus. All isolates from the lungs and nasal turbinates of recipients of two of the four Udorn/72-ts-1[A] recombinants contained only ts virus. These two properties, restricted replication and genetic stability after replication in vivo, suggest that the Udorn/72-ts-1[A] recombinants should be considered for evaluation as vaccines for use in humans.


Temperature-sensitive mutants of influenza A virus. XII. Safety, antigenicity, transmissibility, and efficacy of influenza A/Udorn/72-ts-1[E] recombinant viruses in human adults. The influenza A/Hong Kong/68-ts-1[E] virus (shutoff temperature, 38 C), which possesses many characteristics desirable in a vaccine virus, was used as a donor of its two temperature-sensitive (ts) lesions to the antigenically divergent influenza A/Udorn/72 wild-type virus. Two subsets of Udorn/72-ts-1[E] recombinant viruses were evaluated in seronegative volunteers (serum titer of hemagglutination-inhibiting antibody, less than or equal 1:8). The first subset, represented by clone 13, possessed a shutoff temperature of 39 C and only one of the two ts lesions; this virus was insufficiently attenuated for use in humans. The other subset, represented by clones 16 and 24, possessed both ts lesions and a shutoff temperature of 38 C, like that of its Hong Kong/68-ts-1[E] parent. This subset, also like its ts-1[E] parent, was adequately attenuated, nontransmissible, and protective against intranasal challenge with wild-type Udorn/72 virus. The attenuation manifested by the ts mutants was not a result of their cloning in bovine kidney tissue or replication in eggs. The results suggest that the Hong Kong/68-ts-1[E] virus can be considered for use as a master strain for donation of ts lesions and thus could bring about predictable attenuation of new wild-type influenza A viruses.


Effect of cyclophosphamide on in vitro phagocytosis of Staphylococcus aureus. An increase in susceptibility to infection in an untoward effect common to nearly all immunosuppressive agents. The present investigation was designed to examine potential causes of this decreased resistance to disease. Rats were treated with low dosages of cyclophosphamide, and the effect of such therapy on the in vitro phagocytic capabilities of polymorphonuclear leukocytes was examined. Intracellular destruction of phagocytized bacteria was not significantly altered as a result of treatment. However, the ingestion of Staphylococcus aureus was significantly impaired in the presence of serum from treated animals. Enzymatic analyses for various hydrolytic enzymes associated with reticuloendothelial tissue were also undertaken. Decreased levels of acid phosphatase within alveolar tissue was the only significant change noted as a result of treatment. The reduced phagocytic powers and enzyme levels observed in this investigation offer a partial explanation for the increased susceptibility to disease after treatment with cyclophosphamide.


Age-related susceptibility to infection with canine distemper virus in gnotobiotic dogs. The influence of age on the susceptibility of gnotobiotic dogs to infection with virulent canine distemper virus (R252-CDV) was studied. Of the dogs infected at less than one week of age, 85% died of acute encephalitis two to five weeks after infection. In contrast, only 28.5% of infected weanling and 33.3% of infected adult dogs died after receiving inoculations of R252-CDV. Furthermore, about one-half of the fatally infected weanling dogs developed chronic encephalitis characterized by infiltration of lymphocytes and plasma cells in areas where demyelination of the central nervous system had occurred. Age-related susceptibility correlated with in vitro responses of peripheral blood lymphocytes to phytomitogens. The results of this study suggest that physiological immaturity of the immune system of neonatal dogs may account for their increased susceptibility to infection with CDV.


Olfactory esthesioneuroblastoma.

Olfactory esthesioneuroblastoma. Esthesioneuroblastomas are malignant tumours, usually of slow, invasive growth and low metastatic rate. Skeletal destruction must be assumed to be common, but is often demonstrable only by tomographic sections. Clinically these tumours do not differ from others of the same site, so that the diagnosis has to be based upon the histological appearances. In the light microscope the presence of neurofibrils is considered a specific differential diagnostic factor against other small-cell malignant tumours in this region. There seems to be no basis for a morphological classification into previously described sub-groups, neither according to histogenetic, light, nor ultra-microscopic findings. The general degree of differentiation and the number of mitoses appear to be the main factors of prognostic significance. Combined irradiation and surgical excision is considered the best treatment.


Cinefluorography in the diagnosis of pharyngeal palsies. (1) The aetiology of dysphagia may be difficult to diagnose when it presents without clinical signs or an associated clinical syndrome. (2) Pharyngeal palsies present in acute and chronic forms. (3) Cinefluorographic techniques are helpful in making an objective diagnosis of pharyngeal palsy. (4) Advice may be given to the patient on head and neck positions during swallowing that is based on the findings of the cinefluorographic examination, in order to alleviate symptoms. (5) Good fluoroscopy, preferably with video-tape recording facilities may be perfectly adequate provided that the diagnosis is considered at that time.


Globus hystericus-a psychosomatic disease? Twenty patients with a chief complaint of a lump in the throat, were examined otolacyngologically, radiographically, and psychiatrically with special attention directed to psychosomatic aspects. The control material consisted of matched sample persons of the general population, and of the total patient material treated at a general hospital.


A single average crossed acoustic response. Although the Crossed Acoustic Response is the simplest objective test of hearing acuity, as it can be used without an anaesthetic in the mobile child, a serious obstacle to its wide use has been cost. This was because two averagers have been necessary. This paper describes a modification of the equipment which is not only cheap but which can be used to adapt any existing electrocochleograph or cortical evoked response recorder.


Immunoelectrophoretic study of proteins in middle ear effusion. A study of secretory otitis media in children. An immunoelectrophoretic study of the proteins of middle ear effusions in children with secretory otitis media is described. The findings support the view that the effusion is an exudate as a result of mucosal reaction. The protein content of the fluid appears to decrease as the condition becomes more chronic, and this seems to be enhanced by antibiotic treatment. In cases of bilateral disease, the ears may be in a quite different pathological phase, thus each ear should be treated independently.


Rhabdomyoma of the hypopharynx and larynx. Report of two cases and a review of the literature. Two cases of extracardiac rhabdomyoma are reported in a 54-year-old man with unexplained difficulty in breathing and in a 39-year-old man with a prolonged history of hoarseness. Attention is drawn to the necessity of doing hypopharyngo-and  laryngoscopy in such cases. One tumour was found in the left vallecula in the hypopharynx and the other on the left vocal cord. The literature and the histological findings in 53 cases are reviewed. It appears that this rare tumour is most frequently found in muscles derived from the pharyngeal arches. A total of 40 cases have been diagnosed during the last decade, and this increase is likely to continue in the future. It may turn out that extra-cardiac rhabdomyoma is not so rare as was first presumed.


Primary anaplastic giant cell adenocarcinoma of the larynx. Anaplastic giant cell adenocarcinoma is an extremely rare tumour arising in the bronchial mucosa. This report describes an example--the first to be reported--of such a tumour evidenced in the subglottic region in a 64-year-old man. Histologically, the tumour resembles that arising in the lung and its morphological characteristics justify a distinction of anaplastic giant cell adenocarcinoma from other types of laryngeal malignant epithelial tumours. As to its histogenesis, the neoplasm is most probably of glandular origin and should be considered as a dedifferentiated adenocarcinoma. The patient, who had undergone total laryngectomy followed by X-ray treatment, is alive one year after surgery.


Sudden deafness. A histopathological study. Histopathological studies were performed in the temporal bones from a 77-year-old woman who had bilateral sudden deafness 31 years before her death. The common findings in both cochleas were atrophy of the organ of Corti and stria vascularis, and degeneration of the tectorial membrane. Pathology of the tectorial membrane consisted of atrophy and droplet formation of the middle and marginal zones. In one area, an atrophied tectorial membrane was lifted up by a mass on the limbus. The saccular wall in the left temporal bone was ruptured. There was no pathology in the vascular system in the labyrinths except for moderate degeneration of sensory epithelium. The pathogenesis of sudden deafness was discussed in the light of the present findings. Alteration of the tectorial membrane seemed to be the main factor as a possible cause of sudden deafness. Histopathological findings were reviewed from the literature.


Acoustic trauma from the bone cutting burr. The amplitudes of the stapes footplate movements were determined in human temporal bones when the ossicular chain was drilled with a cutting and a diamond burr. High movements result in comparison to physiological data. The frequency distribution resembles the dB (A) curve. The intensity compared to sound pressure levels on the ear drum is higher than I30 dB. The pressure is constant over the period of contact between the burr and the ossicle. Most likely these unphysiologic movements of the stapes footplate can cause inner ear damage as we had to admit in a case of facial nerve decompression.


Congenital cholesteatoma causing meningitis and death. A case of fatal congenital cholesteatoma in a 71-year-old patient is reported. The presenting symptom was facial paralysis, which was treated symptomatically by a general practitioner and ophthalmologists. Ear discharge, convulsion and coma appeared as final events. It is emphasized that all cases of idiopathic facial paralysis should be referred to the otologist for an evaluation in depth.


Intratympanic keratoma following grommet insertion. An intratympanic keratoma following myringotomy and multiple Shepard's grommet insertions is presented.


Effect of alpha-melanocyte-stimulating hormone and testosterone on cutaneous and modified sebaceous glands in the rat. The effects of alpha-MSH and testosterone propionate on sebum secretion, sebaceous gland volume, dermal lipogenesis, and preputial gland weight and lipogenesis were examined in hypophysectomized rats. Hypophysectomy reduced sebum secretion, sebaceous and preputial gland size, and dermal and preputial gland lipogenesis. The greatest effects were seen on the biosynthesis of wax esters and squalene. Testosterone propionate (TP) increased sebum secretion, sebaceous gland volume and preputial gland weight and lipogenic activity, but had no significant effect on the pattern of lipid labelling. alpha-MSH had no effect on sebaceous or preputial gland size, but increased sebum secretion and dermal lipogenesis, especially wax ester biosynthesis. When given together TP and alpha-MSH had a synergistic effect on sebum secretion and on dermal and preputial gland lipogenesis, and the pattern of lipid labelling was shifted towards normal. TP and alpha-MSH also showed synergism in increasing preputial gland weight, but together they had no greater effect on sebaceous gland volume than that achieved with TP alone. These results suggest that TP and alpha-MSH have different actions on the sebaceous glands with alpha-MSH acting predominantly on lipogenesis and TP on cellualr proliferation and turnover leading to an increase in gland size. Preputial glands differ from cutaneous sebaceous glands in their response to alpha-MSH and androgen which could be a reflection of their more specilized function.


Production of male pseudohermaphroditism in rats by two new inhibitors of steroid 17alpha-hydroxylase and C 17-20 lyase. Two new synthetic steroid analogues, (I) 16beta-bromo-3beta,17alpha-dihydroxy-5alpha-pregnane-11,20-dione and (II) 17beta-ureido-1,4-androstadien-3-one have been shown to give kinetic patterns consistent with active-site-directed irreversible inhibition of adult rat testicular microsomal steroid 17alpha-hydroxylase and C17-20 lyase in vitro. Administration of both analogues to adult male rats for 24 h produced potent inhibition of these testicular enzymes in vivo. Given to pregnant rats during the critical period of male organogenesis they produced hypospadias: a characteristic of the syndrome in man in which these enzymes are defective genetically. Given to male rat pups during the first 9 days of life, inhibitor II produced significantly smaller prostates and seminal vesicles in adulthood, indicating the usefulness of this inhibitor in studies on the role of testosterone in neonatal programming of target organ size in adulthood. Thus, two new enzyme inhibitors have been shown to block testosterone production in the foetal and neonatal rat selectively at the site of the hydroxylase without other apparent hormonal effects or influence on adrenal size.


Androstanediol sulphates in peripheral blood of immature rats and some of their biological effects. The conjugation of 5alpha-androstane-3alpha,17beta-diol (3alpha-A) and its 3beta epimer (3beta-A) was determined in the peripheral blood of immature female rats. About two thirds of these steroids were present in blood as sulphates and one third as glucuronides; no free steroids were detected. Administration of 3beta-A sulphate (25mug/100 g body weight/day) and of 3alpha-A sulphate (50 mug/100 g/day) from day 21 of life until the day of vaginal opening, advanced the day of the first ovulation. Administration of the 3beta-A sulphate did not induce precocious vaginal opening whereas the free alcohol was active in this respect. Implantation of 3beta-A sulphate, but not of the 3alpha epimer, into the basal medial hypothalamus resulted in the dealth of all animals within 24 h.


Interactions of oestradiol-17beta and tamoxifen in the uterus of the pregnant rat. Measurement of the uptake and retention of a radioactive post-coital antifertility agent tamioxifen, by reproductive tissues of the rat have shown that the ovary retained more radioactivity than did any other reproductive organ. Studies have also been made of the uptake and distribution of [3H]tamoxifen and [3H]oestradiol-17beta in the uterus of the pregnant rat on days 2-6 post coitum. Twenty-four hours after administration of tamoxifen, either i.v. or orally, 40-50% of the radioactivity was in the high speed pellet, 10-20% in the nuclear fraction, and 15-30% in the cytosol. An equivalent dose of [3H]oestradiol-17beta yielded distributions of 5%, 5% and 82% respectively. Fractionation of uteri from animals given 0-2  mg tamoxifen/kg on Day 2 of pregnancy followed by [3H]oestradiol 60 min before death showed little difference in total uptake of oestradiol or distribution in the subcellular fraction on Days 4,5 and 6. Although uptake of oestradiol by uterine nuclei was reduced on Day 3 by previous administration of tamoxifen on Day 2, appreciable quantities were still bound to the nuclear receptors. Treatment of ovariectomized animals with tamoxifen at doses up to 40 mug/rat (i.e.  0-2 mg/kg) led to the accumulation of oestrogen-receptor complex in the nucleus. It is concluded that the antifertility properties of tamoxifen (under the conditions of these experiments) cannot be ascribed to the suppression of uptake and binding of oestradiol by the uterus.


Vasopressin release during ventriculo-cisternal perfusion with prostaglandin E2 in the dog. In an attempt to determine whether prostaglandin E2 (PGE2) can act centrally to affect the release of vasopressin (ADH), the ventriculo-cisternal system of anaesthetized dogs was perfused with PGE2. When PGE2 was perfused at a rate of 76-4 ng/min (0-19 ml/min), the plasma ADH concentration was unchanged. However, perfusion of PGE2 at a rate of 152-8 ng/min (0-19 ml/min) resulted in a significant increase in the plasma ADH concentration from the control value of 9-0 +/- 2-2 (S.E.M.) to 18-8 +/- 3-9 muu./ml at 10 min and to 41-0 +/- 16-7 muu./ml at 30 min after the start of the perfusion. There were no changes in arterial blood pressure, rectal temperature, plasma osmolality, and the plasma concentrations of sodium and potassium. In additional experiments, i.v. injection of indomethacin (2 or 20 mg/kg) decreased the plasma ADH concentration by approximately 50%. Although this finding is consistent with a role of PGE2 in the control of ADH release, it could also have been due to the observed increases in arterial blood pressure and effective left atrial pressure. Plasma renin activity was unchanged in the indomethacin experiments. It is concluded that PGE2 can act in the central nervous system to stimulate ADH release.


Changes in brain, pituitary and uterine cytoplasmic oestrogen receptors induced by oestradiol-17beta in the ovariectomized rat. The oestrogen specific, high-affinity cytosol receptor receptor (HAR) from amygdala, anterior, middle and posterior hypothalamus, pituitary and uterus was studied in the ovariectomized rat. A single in-vivo injection of oestradiol-17beta produced significant changes in both the tissue HAR concentrations and the apparent dissociation constants (Kd) determined in vitro. Four hours after oestradiol-17beta treatment (20 mug/kg), the HAR concentration was depleted in all tissues except the posterior hypothalamus. A lower dose of oestradiol-17beta (4 mug/kg) produced similar changes in HAR concentration with the exception of those in the amygdala and posterior hypothalamus. Twenty-four hours after oestradiol-17beta, HAR concentrations had returned to pre-injection levels in all tissues except the uterus. The uterine HAR concentrations were raised after both doses of oestradiol-17beta. The apparent tissue cytosol Kd values were decreased by both doses of oestradiol-17beta. The results suggest that brain, pituitary and uterine oestrogen cytosol HARs react to plasma oestrogen in a manner predictable by the steroid receptor hypothesis. The oestradiol-17beta-induced differential effects upon the tissue cytosol concentration may contribute to the overall spectrum of action of oestrogen in the central and peripheral reproductive processes.


Control of glycolytic enzymes by androgens in the rat epididymis. The influcnce of steroids on the specific activities of glycolytic enzymes was studied in the caput and cauda epididymidis of the rat. In castrated animals, increases in enzyme activities were induced by the administration of androgenic steroids whilst oestradiol and progesterone were without effect. On the other hand, the "antiandrogenic" steroid, cyproterone acetate (16 mg/kg per day for 2 weeks) did not cause a decrease in enzyme activities when administered to animals with ligated efferent ducts. Not all glycolytic enzymes responded to androgens, but more enzymes responded in the caput than in the cauda epididymidis. Administration of testosterone propionate to castrated animals demonstrated that maximum enzyme activity was produced at a dose of 0-1 mg/kg per day whilst higher doses were required to achieve maximum weight of the epididymis, seminal vesicles and prostate. Following castration of animals with ligated efferent ducts, no changes in enzyme activities were observed for approximately 2 days, but then activities declined over the next 2 weeks. When testosterone propionate was administered to castrated animals, a similar lag of approximately 2 days occurred before enzyme activities began to increase.


Effects of propranolol on changes in heart rate, heart weight, kidney weight, urinary hydroxyproline and weight gain induced by large doses of thyroxine in the rat. The effects of the beta-adrenergic receptor blocking agent, DL-propranolol, and of the antithyroid drug, carbimazole, upon some manifestations of thyroxine (T4)-induced changes in peripheral metabolism were studied in rats. Propranolol lowered the heart rate, but did not alter the following changes induced by T4: increment in heart rate, increase in heart or kidney weight, increase in urinary hydroxyproline, decrease in body weight gain or increase in serum T4. Carbimazole administration lowered serum T4 and reduced weight gain, but had no effect upon heart rate or hydroxyproline excretion.


Effects of promazine, chlorpromazine, d-amphetamine, and pentobarbital on treadle pressing by pigeons under a signalled shock-postponement schedule. The effects of promazine on treadle pressing to postpone the presentation of electric shock were studied in three pigeons. The effects of chlorpromazine, d-amphetamine, and pentobarbital were studied in two of these pigeons. Each treadle press postponed electric shock for 20 sec and presentation of a preshock stimulus for 14 sec. Selected doses of both promazine and chlorpromazine increased the rates of treadle pressing in all birds. The response-rate increases produced by promazine and chlorpromazine were due to increased conditional probabilities of treadle pressing both before and during the preshock stimulus. d-Amphetamine (1 and 3 mg/kg) slightly increased responding in one of the birds, but not to the extent that promazine or chlorpromazine did. In the other bird, the 10 mg/kg dose of d-amphetamine increased shock rate but did not change response rate. Some doses of d-amphetamine increased the conditional probabilities of responding both in the absence of the preshock signal and during the preshock signal in both birds. Pentobarbital only decreased response rates and increased shock rates.


The effects of d-amphetamine on the temporal control of operant responding in rats during a preshock stimulus. The operant behavior of six rats was maintained by a random-interval schedule of reinforcement. Three-minute periods of noise were superimposed on this behavior, each period ending with the delivery of an unavoidable shock. Overall rates of responding were generally lower during the periods of noise than in its absence (conditioned suppression). These suppressed response rates also exhibited temporal patterning, with responding becoming less frequent as each noise period progressed. The effects of d-amphetamine on this behavioral baseline were then assessed. In four animals the relative response rates during the noise and in its absence suggested that the drug produced a dose-related decrease in the amount of conditioned suppression. However, this effect was often due to a decrease in the rates of responding in the absence of the preshock stimulus, rather than to an increase in response rates during the stimulus. Temporal patterning in response rates during the preshock stimulus was abolished, an effect that was interpreted in terms of rate-dependent effect of d-amphetamine. This study thus extends rate-dependent analyses of the effects of amphetamines to the patterns of operant behavior that occur during a preshock stimulus, and which have been discussed in terms of the disrupting effects of anxiety on operant behavior.


On the determination of the dorso-ventral polarity in the amphibian embryo: suppression by lactate of the formation of Ruffini's flask-cells. Cells isolated from the vegetal hemisphere of the blastula of Ambystoma mexicanum differentiate spontaneously into fibroblast-like cells. Similar cells may be formed from animal cells, provided they are induced either by vegetal cells or by Li+. We have found that lactate and various inhibitors of RNA synthesis suppress the spontaneous cell differentiation. The effect of lactate differs from that of the other agents in so far as lactate must be present before the second day of culture to suppress the outgrowth of fibroblasts on the third day; the other inhibitors are active also when added on the second day. An explanation of this difference may possibly be found in the fact that lactate suppresses incorporation of RNA but only by 40%. The effect on the differentiation of various substances supposed to interfere with the metabolism of lactate was established. The results obtained were suggestive, but not conclusive. It is concluded that the effect of anaerobiosis may be explained as a lactate inhibition. The amounts of lactate under aerobic conditions are so slight that it is unlikely, but not impossible, that lactate is directly involved in the control of differentiation.


Biochemical and cytochemical studies on adenylate cyclase activity in the developing rat submandibular gland: differentiation of of the acinar secretory compartment. To investigate membrane changes in development of the exocrine cells of the rat submandibular gland (SMG), biochemical and cytochemical studies of adenylate cyclase activity were performed on prenatal and postnatal glands. SMG rudiments and glands were studied from 15 days of gestation op to birth and 1, 2, 3, 4 and 24 weeks after birth. Glands were chemically assayed for adenylate cyclase activity using the procedures of Salomon and coworkers and cytochemically studied using a procedure which was verified biochemically. At 15-16 days of gestation basal adenylate cyclase activity was low and no staining could be observed. Adenylate cyclase activity rose six-fold from the 16th to the 18th day of gestation. Adenylate cyclase staining became evident along the surface of most of the cells of the rudiment at this time. Basal adenylate cyclase activity remained relatively constant from the 18th day of gestation up to 24 weeks of age. However, sequential changes were seen in the cytochemical localization, especially in relation to the apical plasma membrane of the developing secretory cells.


The use of variable lactate/malic dehydrogenase ratios to distinguish between progenitor cells of cartilage and bone in the embryonic chick. The activities of LDH and MDH have been studied, both in differentiated cartilage and bone from the embryonic chick, and in the pool of mixed osteogenic and chondrogenic stem cells found on the quadratojugal, a membrane bone. In confirmation of the model proposed by Reddi & Huggins (1971) we found that the LDH/MDH ratio was greater than 1 in cartilage and less than 1 in bone. Furthermore we established, for the first time, that ratios occurred in the chondrogenic and osteogenic stem cells, similar to the ratios in their differentiated counterparts. Alteration in LDH/MDH resulted from variations in the level of LDH/mug protein. MDH/mug protein remained constant, even when LDH/MDH was changing. We interpret these results in terms of adaptation of chondrogenic progenitor cells for anaerobic metabolism and anticipate that our model will be applicable to other skeletal systems where stem cells are being studied.


Fish swimbladder: an excellent mesodermal inductor in primary embryonic induction. Swimbladder of the crucian carp, Carassius auratus, was found to be better as a vegatalizing tissue than other tissues, such as guinea-pig bone marrow, when presumptive ectoderm of Triturus gastrulae was used as reacting tissue. Swimbladder usually induced assemblies of highly organized mesodermal tissues, such as notochord, somites and pronephric tubules, some of which were covered by mesodermal epithelium without any epidermal covering. A special character of the effect of swimbladder was the rather frequent induction of solid balls of undifferentiated cells, which were identified as mesodermal or mesodermal and probably endodermal. These findings show that swimbladder has a strong and fast spreading vegetalizing effect on the responding presumptive ectoderm.


Embryological study of a T/t locus mutation (tw73) affecting trophectoderm development. Mouse embryos homozygous for the recessive lethal mutation tw73 show specific defects in trophectoderm shortly after implantation. The trophectoderm and ectoplacental cone fail to form the usual close association with the uterine decidua, and proliferation is markedly reduced. The embryo proper ceases to develop beyond the two-layered stage and degenerates and dies within 5 days of implantation.


The development of Drosophila embryos after partial u.v. irradiation. U.v. irradiation of the anterior pole of nuclear multiplication stage Drosophila eggs produces embryos with defective anterior structures. At a low frequency embryos resembling some phenotypes of the bicaudal syndrome of Drosophila were observed. These embryos had no head or thorax and the eight abdominal segments were spread to the anterior of the embryo. Sometimes spiracles, characteristic of the most posterior embryonic segment were observed at the anterior of the embryo. The development of these embryos was followed, and abnormalities occurred as early as blastoderm formation. The extent of the blastoderm defects correlated well with the final abnormality in the embryo.


Cell junctions in the developing compound eye of the desert locust Schistocerca gregaria. Intercellular junctions in the developing retina of the locust Schistocerca gregaria have been examined by electron microscopy. Different types of junction appear in a well defined sequence during development. Five stages of ommatidial development are described. Close junctions and punctate junctions are present throughout development. Gap junctions appear transiently amongst the undifferentiated cells, before clearly defined preommatidia can be distinguished. The subsequent disappearance of gap junctions may be correlated with cell determination. Lanthanum studies confirm these findings. The later sequential appearance of adhesive junction types is described. These include septate desmosomes and two types of desmosomes. In the fully differentiated ommatidium only two types of junction remain, these are: desmosomes and rhabdomeric junctions.


Comparative analysis of cell distribution in the pigment epithelium and the visual cell layer of chimaeric mice. In chimaeras of both rdrdCC in equilibrium ++ cc and rdrdcc in equilibrium ++CC combinations two types of distribution were observed. In a majority of the chimaeras both retinal layers were chimaeric; whereas in a few cases the pigment epithelium was chimaeric but the visual cell layer was made of ++ cells only. No spatial relation was observed in the distribution of the cells in the two layers. The two eyes of the individuals were nearly always identical with regard to occurrence of chimaerism in the two layers. The findings are discussed in the light of the possible site and mode of expression of the rd gene.


The effects of a t-allele (tAE5) in the mouse on the lymphoid system and reproduction. Mice homozygous for tAE5, a recessive allele at the complex T-locus, are characterized by their unique short-tailed phenotype as well as by runting and low fertility. Histological and histochemical studies of the lymphoid and reproductive systems disclosed structural changes in the mutant spleen resembling those found in autoimmune conditions. Involution of the mutant thymus was greatly accelerated compared to normal. Necrotic changes occurred during spermiogenesis whereas ovarian structure was normal in mutants. The possible mechanisms of the mutant effects are discussed in the framework of other similar syndromes and the mode of action of alleles at the complex T-locus.


The neuronal basis of a sensory analyser, the acridid movement detector system. I. Effects of simple incremental and decremental stimuli in light and dark adapted animals. 1. The response of the movement detector (MD) system to proportionally constant incremental and decremental stimuli has been studied at various degrees of light and dark adaptation. Action potentials in the descending contralateral movement detector neurone were taken as the indicator of response. 2. Over a range of at least six log10 units of adapting luminance, the MD system behaves as an ON/OFF unit, giving responses to both incremental and decremental changes in the illumination of a 5 degrees target. 3. With increasing amplitudes of stimuli, both the ON and OFF responses saturate rapidly. Saturation is reached sooner at higher levels of light adaptation. At all levels of light adaptation, the OFF response is greater than the ON. The ratio for saturating stimuli is approximately constant at around 3:2. 4. At the brightest adapting luminances used (20 000 cd/m2) the ON response is reduced but not lost. At the lowest (0-004 cd/m2) the OFF response to a 5 degrees disc fails, but can be regained by increasing the test area to 10 degrees. 5. From what is known of the retina of locusts and other insects, it is thought that light and dark adaptation in the MD system can be adequately explained by events at the retinula cell.


The respiratory responses of Carcinus maenas to declining oxygen tension. The degree of respiratory independence shown by Carcinus under conditions of declining oxygen tension is dependent on the animal's level of activity. Inactive Carcinus are capable of maintaining respiratory independence down to a Po2 of 60-80 mmHg. This is achieved primarily by an increase in ventilation volume such that the amount of oxygen made available at the respiratory surfaces remains constant over a wide range of oxygen tension. The Po2 at which this can no longer be maintained corresponds closely to the Po2 at which respiratory independence is lost. Under normoxic conditions the Po2 of the post- and prebranchial blood was 97 and 18 mmHg respectively. At the high oxygen tensions prevailing in the postbranchial blood the respiratory pigment is fully saturated. Under conditions of declining oxygen tension the heart rate remains more or less constant  until the Po2 reaches 60-80 mmHg, the onset of bradycardia coinciding with the loss of saturation of the haemocyanin. Although cardiac output falls during hypoxia, the capacity rate ratio remains approximately constant, which enables the effectiveness of oxygen uptake by the blood to remain at a high level.


Fluid secretion by the malpighian tubules of the tsetse fly Glossina morsitans: the effects of ouabain, ethacrynic acid and amiloride. The effects of three inhibitors of sodium transport on the secretion of fluid by the Malpighian tubules of Glossina morsitans have been observed. The cardiac glycoside, ouabain, affects neither the rate of secretion nor the sodium concentration of the fluid secreted when isolated tubules are bathed by solutions containing a range of sodium and potassium concentrations. Secretion is inhibited, however, by ethacrynic acid and amiloride. The results confirm that fluid secretion by the Malpighian tubules of this insect is dependent on the active transport of sodium ions and show that Na+/k+ exchange pumps are not involved in this process.


Active transport of calcium across the isolated midgut of Hyalophora cecropia. 1. The net flux of 45Ca from lumen to blood side across the isolated and short-circuited Cecropia midgut was 1-9 +/- 0-2 muequiv. cm-2h-1 in 8 mM Ca and the flux ratio was as high as 56 to 1. 2. The calcium influx was depressed by anoxia; 73% after 30 min. 3. The kinetics of Ca transport were anomalous; the apparent Km varied with Ca concentration from less than 0-2 to greater than 5-6 mM Ca and the apparent Vmax varied from less than 1-3 to greater than 3-3 muequiv. cm-2h-1. 4. The calcium influx showed a delay before the tracer steady state was attained, indicating the existence in the transport route of a calcium pool equivalent to 5-7 muequiv/g. wet weight of midgut tissue. 5 High calcium (16 mM) depressed the short-circuit current and potassium transport from blood to lumen side across the midgut. 6. Calcium depressed magnesium transport, from lumen to blood side across the midgut, and magnesium depressed the calcium transport. 7. Ca transport by the midgut does not regulate the Ca level in the haemolymph in vivo; it merely aids the diffusion of calcium down its electrochemical gradient. However, Ca transport may assist the uptake of the nutrients from the midgut contents.


Importance of air and water breathing in relation to size of the African lungfish Protopterus amphibius Peters. 1. Oxygen uptakes from air and water have been measured in relation to weight of the African lungfish Protopterus amphibius Peters. 2. Combined O2 uptake from air and water ranged from 60 ml O2 kg-1 h-1 STPD, in a 3-7 g specimen, to 30 ml O2kg-1 h-1, in a 255 g specimen. 3. While the combined O2 uptake changed by a factor of 2, within the weight range under study, the aquatic O2 uptake changed 8-fold within the same range. The smaller fish satisfy 70% of their O2 requirement by aquatic breathing compared to 10-15% in the grown specimens. 4. The pattern of bimodal breathing in P. amphibius is discussed in relation to the natural habitat of the species.