Relationship between the suckling-induced release of oxytocin and prolactin in the urethane-anaesthetized lactating rat. The effects of changes in the intensity of the suckling stimulus on the reflex release of oxytocin and prolactin were compared in urethane-anaesthetized lactating rats. Mothers which had previously suckled 12 pups (Group 1) showed a graded increase in the amount of oxytocin released during a 3 h suckling test when the number of pups applied to the nipples was increased from six to eight or ten. Mothers which had suckled six pups during their lactation (Group 2) appeared to show a maximum frequency of milk ejection whether six, eight or ten pups were applied to the nipples. The release of prolactin was not elicited from either Group 1 or Group 2 mothers when six pups were applied to their nipples. With eight pups suckling, the Group 1 mothers again showed no evidence of prolactin release. In contrast, the Group 2 mothers showed a significant increase in the level of prolactin in the plasma during the 3 h suckling test. With ten pups suckling the release of prolactin was evident in both groups of mothers, although the response was earlier and more pronounced in Group 2 than Group 1. These results suggest that in the urethane-anaesthetized rat, the threshold for the suckling-induced reflex release of oxytocin is distinct from the threshold for the release of prolactin and that these thresholds are, at least in part, set by the preceding suckling experience of the mothers. In those animals which showed both reflex milk ejection and prolactin release there was a linear relationship between the magnitude of the two endocrine responses.


Influence of fasting, glucose and insulin on the levels of growth hormone and prolactin in the plasma of the domestic fowl (Gallus domesticus). The concentrations of both GH and prolactin in the circulation of the domestic fowl have been determined after various treatments known to affect carbohydrate metabolism. Fasting decreased the level of glucose, stimulated the secretion of GH and inhibited the secretion of prolactin. Administration of insulin significantly depressed the level of GH in the plasma of normal or fasted birds and also in chickens which had received simultaneous injections of glucose or 2-deoxy-D-glucose. No consistent effect of insulin on the secretion of prolactin was observed. Hyperglycaemia subsequent to administration of glucose had no effect on the levels of either GH or prolactin. Glucagon-induced hyperglycaemia suppressed the level of GH in the plasma and stimulated that of prolactin.


Separation of relaxin activities in extracts of ovaries of pregnant sows by polyacrylamide gel electrophoresis. Polyacrylamide gel electrophoresis has been employed to separate three fractions that have relaxin activity from crude extracts of ovaries of pregnant sows. Bioassays indicated that all fractions had the ability to inhibit spontaneous uterine contractions in vitro and to induce formation of interpubic ligaments in oestrogen-primed mice. The presence of the various fractions in crude extracts of sow ovaries was monitored with the polyacrylamide gel system on days 40, 70 and 100 of pregnancy. Both the total amount and the relative proportions of the fractions were found to change as pregnancy progressed.


Relationship between follicle-stimulating hormone, androstenedione and oestradiol in human follicular fluid. The concentrations of FSH, oestradiol and androstenedione in the follicular fluid of normal and cystic human follicles were measured at different stages of the menstrual cycle. In addition, the number of granulosa cells in the follicles was determined. In follicles in which FSH was detectable, the concentration of oestradiol was greater than that of androstenedione, irrespective of the stage of the cycle. In contrast, in those follicles in which FSH was undetectable and in all cystic follicles irrespective of the level of FSH, the concentration of androstenedione was greater than that of oestradiol. In follicles containing FSH there was a highly significant linear correlation between the number of granulosa cells and the concentration of follicular oestradiol (P less than 0.001). It is suggested that in human ovaries up to 90% of the oestradiol in follicular fluid may originate from the granulosa cells.


[The effect of hybridization on the embryonic germ cell population and the young females produced by the crossing of a male Peking duck with a female Barbary duck (Anas platyrhynchos x Cairina moschata)]. Ovarian development has been studied in a hybrid duck (Anas platyrhynchos male x Cairina moschata female) and in females of the parental Peking and Barbary species. In the hybrid, the gonadal ridge when it first forms is smaller than in either parental species, and after 16 days of incubation there is less cortical growth and less oogonial proliferation. At hatching, the left ovary of the hybrid contains fewer follicles, perhaps because the reduced size of the hybrid gonadal ridge limits germ cell colonization. However, the hybrid follicles develop very rapidly after hatching, and laying begins earlier in the hybrid than in Peking and Barbary ducks.


Changes of organelles associated with the differentiation of epidermal melanocytes in the mouse. Electron microscopic observations on normally differentiating and alpha-MSH (melanocyte-stimulating hormone)-treated epidermal melanocytes of newborn mouse skin were carried out. The process of melanocyte differentiation from premelanosome-containing melanoblasts was investigated in detail with respect to melanosomes as markers. Melanoblasts containing unmelanized premelanosomes gradually decreased in number after birth, while the number of melanocytes rapidly increased. The epidermis of alpha-MSH-treated 3-day-old mice and normal 6-day-old mice contained melanocytes with numerous fully melanized melanosomes, and with no or only a few melanoblasts. Changes in other organelles in differentiating melanocytes were also noticeable. Golgi apparatus and RER (rough endoplasmic reticulum) decreased in number during the normal or alpha-MSH-induced differentiation of the epidermal melanocytes, though the number of mitochondria showed no notable change. The number of SER (smooth endoplasmic reticulum) per cell did not change in the cells of newborn mice, while in alpha-MSH-treated cells the number increased significantly. These results led us to an assumption that Golgi apparatus or RER transforms into other forms of organelles including melanosomes and SER during the differentiation of melanocytes.


Cell death in the posterior necrotic zone (PNZ) of the chick wing-bud: a stereoscan and ultrastructural survey of autolysis and cell fragmentation. The participation of lysosomes and cell profile changes were studied during mesenchymal cell death in the PNZ of forelimbs of the 4 1/2-day chick embryo. Lysosome participation was studied cytochemically using as substrate either beta-glycerophosphate or p-nitrophenylphosphate. Acid phosphatase (AP) is localized within the Golgi cisternae of the prospective dying cells, and small AP-positive autophagic vacuoles appear when degeneration commences. As degeneration by enzymic digestion proceeds, these vacuoles increase in size and appear to become autolytic since part of the AP activity seems to 'leak' out of the autophagic vacuoles. Next, the cells fragment and the fragments are then enclosed in heterophagic vacuoles of macrophages where digestion is completed. The SEM showed that these intracellular changes in degenerating cells are accompanied by changes in the cell surface structure. First, the degenerating cells lose the stellate appearance of healthy mesenchymal cells and become rounded and pitted, then constrictions appear and finally the cytoplasm breaks up into many small pieces. This final fragmentation may be an active process rather than a mere consequence of vacuolation.


Experimental studies of the shape and structure of isolated cardiac jelly. The properties of the early chick embryonic heart cardiac jelly were studied. The cells of the heart were removed by sequential treatments with calcium magnesium-free medium; the same medium containing 5 mM EDTA; and aqueous 0.1% deoxycholate. The transparent, naked cardiac jelly retained the original shape and size of the untreated original heart when immersed in physiological ionic strength medium. Its size and shape responded to changes in the ionic strength of the surrounding media. Alcian blue, cetylpyridinium chloride and testicular hyaluronidase abolished the ability of the jelly to respond to ionic strength changes. Electron microscope examination of the negatively stained spread cardiac jelly revealed an extensive network of collagenous fibrils and fine filaments with some amorphous adhering material. Treatment with testicular hyaluronidase removed much of the amorphous material and improved the details of the filaments. These results suggest that glycosaminoglycans play an important part in the hydration of the cardiac jelly and that the stability of the cardiac jelly shape is mainly due to the filamentous network and their possible interactions with macromolecules of the cardiac jelly matrix. It is suggested that the factors that control the depositon of the connective tissue macromolecules and the assembly of the filamentous network are significant factors which influence the morphogenesis of the early embryonic heart.


Re-evaluation of the presence of multiple haemoglobins during the ontogeny of the mouse. In mice, three alleles, Hbbs, Hbbd and Hbbp, have been found at the beta-chain locus of haemoglobin. Analytical polyacrylamide gel electrophoresis revealed the presence of almost the same four haemoglobin bands (E-I, E-II, E-III and X) in all of the lysates of peripheral blood cells from 12-day-old foetuses of C57BL/6J (Hbbs), A/He (Hbbd) and PON (Hbbp). All were embryonic-type haemoglobins; the most anodal band (X) seemed to be a product of polymerization of E-I. Electrophoretic patterns of the haemolysates from 12-day-old foetuses were not affected by alkylation with iodoacetamide or maleic anhydride. Almost the same electrophoretic patterns in subunit analysis, using acid starch and acid-urea polyacrylamide gels, were obtained in 12-day-old foetuses of C57BL/6J, A/He and PON. E-I comprised alphia and x-chains, E-II, alpha- and y-chains, and E-III, alpha- and z-chains. In adults, two haemoglobin bands, s and Y, were present in the haemolysate of C57BL/6J, while three, dmaj, dmin and Y, existed in A/He, and three, pmaj, pmin and Y, in PON. All were adult-type haemoglobins. Haemoglobin Y, which was not demonstrable after alkylation of the haemolysates, seemed to be a product of polymerization of major haemoglobins (s, dmaj and pmaj). Each haemoglobin possessed common alpha-chains, while the beta-chains of major haemoglobins were different from those of minor haemoglobins. Developmental changes of the haemolysates from foetuses of C57BL/6J, A/He and PON were similar to each other. Haemolysates of the liver cells of developing foetuses contained only adult-type haemoglobins. Our techniques used here were not able to demonstrate the presence of foetal-type haemoglobins.


The ultrastructure of the mesenchymal element of the palatal shelves of the fetal mouse. The ultrastructure of the mesenchymal element of the palatal shelves of C3H mouse embryos aged 13 days 18 h and 14 days 18 h in utero was studied. At 13 days 18 h the mesenchyme showed a high density of cells. The cells contained a well developed system of rough endoplasmic reticulum and Golgi complex; many were ciliated and multi-vescular structures were common. By 14 days 18 h, many of the mesenchymal cells contained large numbers of glycogen particles. These cells also possessed long cytoplasmic processes which sometimes were seen to contain many filaments 5--7 nm in diameter. Some of the cells also contained a fine filamentous network just below the plasma membrane. Developing mononuclear and binucleate skeletal muscle cells containing myofibrils were present in the posterior region of the palate, with groups of cells which consisted of typical peripheral neurons and their surrounding satellite cells. Both the muscle and nerve cells were only observed in the 14 day 18 h material. It is suggested that both the myofibrils in the skeletal muscle cells and the filamentous network in the mesenchymal cells may play a role in shelf reorientation.


Variability of chimaeras and mosaics.

Variability of chimaeras and mosaics. Aggregation chimaeras and X-inactivation mosaics in mice are alike in general appearance, but chimaeras are very much more variable in the proportions of the cell types (p) seen for example in coat pigmentation. The distribution of p in chimaeras is not binomial, but is uniform, or flat, between the two extremes. The greater variability of chimaeras arises from two sampling events that occur when cellular heterogeneity is already present in chimaeras but before it arises in mosaics. These are the differentiation of the inner cell mass from the trophectoderm and of the primary ectoderm from the primary endoderm. The second of these generates the flat distribution of chimaeras as a consequence of the two cell types being unmixed at that time. The two sampling events generate single-colour individuals in roughly the proportions observed. Consideration of the second sampling event provides evidence that the primordial germ cells must originate in the primary ectoderm and not in the yolk-sac. Estimation of numbers of progenitor cells on the supposition of binomial sampling is not valid unless the clone-size is known or the cells in the sample are not contiguous. Data on coat pigmentation are consistent with the assumptions that X-inactivation is random in about 21 cells, that the sampling of melanoblasts is binomial (because they are not contiguous), and that the melanocytes of the head and body are descended from about 34 progenitor cells.


Feedback inhibition of erythropoiesis induced in anaemic Xenopus. Serum from normal Xenopus, when injected into anaemic Xenopus, causes reduction in both DNA and protein synthesis in erythroid cells as indicated by in vitro culture of the blood cells. Experiments with erythrocyte-conditioned medium, reveal that this inhibitory substance can be recovered from mature erythrocytes. Sephadex G-25 fractionation of normal serum and haemolysate demonstrates that the inhibitory factor consists of molecules of low molecular weight, and experiments with with cells of Xenopus kidney reveal that the feedback inhibition may be tissue specific to erythroid cells.


Compartmentalization and growth of the Drosophila abdomen. An analysis of the cell lineage of the adult Drosophila abdomen is reported. Genetically marked clones are produced in the tergites in the embryo and in the sternites and pleura during larval life. The spatial disposition of the segment primordia is also studied in a series of 250 gynandromorphs. We conclude that in the embryo the segments are all separate polyclones soon after blastoderm and these are probably adjacent to each other. Gynandromorph analysis suggests that segments 2--6 develop from similarly sized cell groups but that the first tergite develops from a primordium which is equal to that of two other segments. We suggest that presumptive adult and larval cells are not separated at blastoderm. Our estimate from clonal analysis of the number of larval cells (12) which construct the sternites and pleura is equal to the number observed directly in the ventral nest of histoblasts.


[Morphogenesis of the imaginal abdominal epidermis in Calliphora erythrocephala (Insecta,Diptera)]. The morphogenesis of the abdominal epidermis in Calliphora erythrocephala begins by a cellular proliferation which proceeds slowly in larvae and rapidly in pupae. This allows histoblasts to glide and invade the whole abdominal surface. As soon as the new epidermal sheet has become continuous, differentiation begins. Generalized epidermal cells show an intense activity which leads to the deposition of imaginal cuticle from the 6th day after pupation onwards. After cuticle deposition they darken and become inactive although they remain alive, even after emergence. Trichogen and tormogen cells are even more active than generalized epidermal cells, especially the trichogen cell in which polyribosomes and microtubules are abundant. The former are possibly involved in microtubule synthesis. After cuticle deposition the trichogen and tormogen cells undergo degeneration. Their nuclei contract, rough endoplasmic reticulum breaks down and cytoplasm breaks up into fragments through infoldings which proliferate from the plasma membrane. Finally only generalized epidermal cells and sensory cells remain alive in the adult.


Limb-somite relationship: effect of removal of somitic mesoderm on the wing musculature. The aim of this study is to test the ability of the intrinsic wing musculature to develop in the absence of somitic mesoderm. The experiments were performed on 2- to 2.5-day chick embryos either by replacing the somitic mesoderm adjacent to the wing field with a piece of 9-day chick embryonic midgut or by destroying, through local X-irradiation, not only the somitic mesoderm of the wing level, but also at least three somites (or presumptive somites) anterior and/or three presumptive somites posterior to the wing level. The replacemnt of somitic tissue scarcely affected the organogenesis of the forearm musculature, at least when both bones were present. In the other experiments, radio-destruction severely impaired the development of the forearm muscles, which were seldom all present and in most cases were entirely missing. The absence of a given muscle involves the simultaneous absence of the corresponding tendons. The possible origins of the muscles that formed despite the removal of the somitic mesoderm are discussed.


Feather-forming capacities of the avian extra-embryonic somatopleure. Blocks of 12.5- or 13.5-day embryonic mouse upper-lip dermis were introduced under the ectoderm of the extra-embryonic area of 2- to 3-day chick or duck embryos. Two kinds of ectopic cutaneous appendages were produced: either arrested feathers alone, or arrested feathers and full-grown feathers. The former developed in the ectoderm overlying the implanted mouse dermal cells, the latter formed in their close vicinity, but contained host dermal cells exclusively. Thus, avian extra-embryonic somatopleure, both ectoderm and mesoderm, possesses the information for feather development: the extra-embryonic ectoderm, if it is brought in contace with an appendage-forming dermis, is able to respond to the dermal induction by initiating feather morphogenesis; the extra-embryonic mesoderm, if it is experimentally transformed into a dense dermis, can express its feather-forming capacity by specifying feather tract morphology and barb-ridge number, thus leading to the acievement of feather morphogenesis.


Teratological evaluation of 5-fluorouracil and 5-bromo-2-deoxyuridine on hamster fetuses. A single intraperitoneal injection of 5-bromo-2-deoxyuridine (BUDR) between days 9 and 11 and a single intramuscular injection of 5-fluorouracil (FU) between days 8 and 11 of gestation were teratogenic in hamster. The malformation frequencies were related to the dose and time of BUDR and FU treatment but the pattern and types of malformations and their frequencies were different. BUDR showed lower embryotoxic effect than FU. Both drugs impaired general fetal growth. It is suggested that the differences between FU and BUDR may be related to the chemical nature and metabolism of the drug and their eventual effect on the species-specific target tissue.


Cartilage matrix deficiency (cmd): a new autosomal recessive lethal mutation in the mouse. A new autosomal recessive lethal mutation in the mouse designated cartilage matrix deficiency (cmd) is described. Homozygotes are dwarfed, and have abnormally short trunk, limbs, tail and snout, as well as a protruding tongue and cleft palate. The abdomen is distended because the foreshortened rib cage and spinal column forces the liver ventrad from its normal location. Histological and electron microscopic study reveals a deficiency of cartilage matrix in tracheal cartilage and in all cartilagenous bones examined. The syndrome closely resembles the rare lethal condition achondrogenesis, found in human infants, which is also believed to be due to an autosomal recessive gene.


Determination of the embryonic origin of the mesencephalic nucleus of the trigeminal nerve in birds. The precise site of origin and the cells of origin of the mesencephalic nucleus of the trigeminal nerve in birds have been studied by the method of growing embryonic fore-, mid- and hind brain grafts inside a millipore filter chamber filled with amniotic fluid, upon a host chorioallantoic membrane, and by the method of transplantation of cranial neural crest of the mesencephalon between embryo-donors and duck embryo-hosts. The growth and differentiation of grafts grown in the chambers resemble very closely those of normal embryos at corresponding stages of development. Data obtained from a total of 42 grafts representative of the three species of birds used in this study, show that the cells of the mesencephalic nucleus are present only in grafts of embryonic midbrain and totally absent in forebrain and hindbrain grafts. The presence of cells of the mesencephalic nucleus in midbrain grafts suggests that these neurons arise chiefly from the developing mesencephalon. Histological examination of such grafts has shown that these neurons are observed in the leptomeningeal tissue overlying the midbrain region and extend into the various laminae of the optic tecta. A progressive increase in the size of the cells from an immature state confined to the mesodermal tissue to fully mature neurons in the stratum griseum periventriculare of the optic tectum is observed. This is also indicative of a downward migration of these cells. In a few embryonic midbrain grafts mature cells clearly identifiable as belonging to the mesencephalic nucleus are observed in the leptomeningeal tissue and outside the external limiting membrane of the neural tube. These appear to be neurons which had failed to migrate. The resemblance of these latter neurons to those in the stratum griseum periventriculare of the optic tectum lend further support to the hypothesis that the neurons of the mesencephalic nucleus are derived from neural crest of the developing mesencephalon in birds. In interspecific transplantation experiments of cranial neural crest of the mesencephalon, the quail cells occur in the form of clusters and appear to migrate towards the ventricular surface independent of the migration of the cells of the tectum which takes place simultaneously. Three stages in the development of the grafted neural crest material of the quail are observed based on the perikaryal diameter of the cells, and the accumulation of Nissl material in the cytoplasm. The smallest cells are located more superficially near the pial surface, and the larger mature neurons are observed in the stratum griseum periventriculare of the optic tectum. All the layers of the optic tectum including the neuroepithelium on the experimental side are comprised entirely of duck cells...


Kinetics and mechanisms for removal of circulating single-stranded DNA in mice. Clearance of exogenous ssDNA from circulation was rapid and occurred primarily through the liver. With higher doses of single-stranded DNA (ssDNA), both liver uptake and whole blood clearance approached a maximum, enabling larger amounts of ssDNA to persist in the circulation. The large molecular weight material (precipitable ssDNA) which remained in circulation was rapidly cleaved to 20,000-30,000 mol wt fragments by endonucleases, at least some of which could be demonstrated in plasma in vitro. Mononucleotide breakdown products appeared rapidly in circulation with no lag phase, suggesting that exonuclease activity was not dependent upon prior phagocytosis. Since no exonuclease activity could be demonstrated in plasma in vitro, it was postulated that breakdown of ssDNA by exonucleases occurs on the surface of hepatocytes of Kupffer cells.


Induction in vivo and in vitro of terminal deoxynucleotidyl transferase by thymosin in bone marrow cells from athymic mice. Terminal deoxynucleotidyl transferase (TdT) expression in bovine serum albumin (BSA) gradient-fractionated bone marrow cells was examined in NIH Swiss nu/nu and thymectomized C57BL/6 mice. In nude mice, TdT levels were approximately 10% of those of thymus-bearing littermates. In C57BL/6 mice, thymectomy caused a time-dependent loss of TdT activity in bone marrow cells. To determine whether or not not the apparent thymic requirement for TdT expression in bone marrow was mediated by thymic hormones, we examined the effects of thymosin fraction 5. Treatment of either NIH Swiss nu/nu or thymectomized C57BL/6 mice with thymosin fraction 5 restored the levels of TdT activity in BSA gradient-fractionated bone marrow cells to normal. Moreover, treatment of BSA gradient-fractionated bone marrow cells from NIH Swiss nu/nu or thymectomized C57BL/6 mice in tissue culture with thymosin fraction 5 induced TdT expression. In tissue culture, TdT induction was optimal with 25 ng/ml of thymosin fraction 5, it occurred within 6 h, and it was completely inhibited by actinomycin D. The effect was specific in that neither control nor spleen fraction 5-treated cells were induced to express TdT. These data demonstrate that TdT expression in bone marrow cells is under the direct control of thymic polypeptide hormones.


Surface and fluid phase activities of two forms of activated Hageman factor produced during contact activation of plasma. The ability of the two forms of activated Hageman factor (HFa) produced during contact activation of plasma to activate prekallikrein and factor XI was studied. alpha-HFa, defined as an 80,000 mol wt two-chain enzyme which remains bound to the surface was capable of cleaving surface-bound prekallikrein and factor XI. beta-HFa, a 28,000 mol wt single chain molecule, released from the surface during contact activation was able to cleave prekallikrein but showed no activity on factor XI. Cleavage of prekallikrein by beta-HFa occurred irrespective of whether the substrate was surface-bound or in solution. Cleavage of factor XI occurred only when it was surface bound and only the alpha-form of HFa was capable of this proteolytic action. Factor XI was found to remain bound to the surface while prekallikrein and kallikrein rapidly dissociated from the surface into the supernate. These findings suggest that the initiation of intrinsic coagulation through the activation factor XI is a localized event occurring at the site of contact activation and is the result of the action of alpha-HFa. By contrast, kinin generation and fibrinolysis resulting from the formation of kallikrein can be initiated either at the site of contact activation, by alpha-HFa action, or throughout the plasma, by beta-HFa; further dissemination of these activities is assured by the rapid dissociation of kallikrein itself from the surface.


Serine enzymes released by cultured neoplastic cells. Serine proteases or esterases released from cell cultures into the growth medium were converted to radioactive derivatives by active site labeling with tritiated DFP, both in the presence and absence of other competing active site reagents. The individual labeled enzymes were then identified by SDS-polyacrylamide gel electrophoresis and scintillation autoradiography. Conditioned medium from embryonal mouse fibroblasts transformed by mouse sarcoma virus contained five serine enzymes that were not present in medium from normal cells; two serine enzymes were released by both cell types, and one serine enzyme was found only in medium from normal cells. Two of the enzymes released by transformed cells were identified as plasminogen activators; these accounted for most of the serine enzyme labeling in transformed culture media and for most of the serine enzyme difference between normal and transformed cultures. The culture fluids from two cell strains of human neoplastic origin were examined by the same method. A rhabdomyosarcoma strain released eight serine enzymes (mol wt ranging from 22,500 to 102,000), four of which were plasminogen activators; seven serine enzymes (mol wt 26,000-102,000), including two plasminogen activators, were detected in medium from human melanoma cultures. In terms of electrophoretic mobility two of the plasminogen activators from rhabdomyosarcoma were identical with those from melanoma cultures, while the remaining two rhabdomyosarcoma activators coincided with activators found in commerical urokinase.


Lysis of oncornaviruses by human serum. Isolation of the viral complement (C1) receptor and identification as p15E. Moloney leukemia virus activated both the classical and alternative pathways of human complement. About 500,000 virions were required to detect activation of the classical pathway whereas 5,000 times as many virions were necessary to initiate the alternative pathway, indicating that in this system only the former is of biological significance. Disruption of the virus with Triton X-100 destroyed its ability to initiate the alternative pathway without affecting its ability to activate the classical pathway. After ultracentrifugation of disrupted virus the active component could be recovered in the supernate and was isolated by isoelectric focusing in granulated gels. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic and analysis and cyanogen bromide digestion studies revealed that the activity resided in a methionine-containing protein having a pI of 7.5 and a molecular weight of approximately equal to 15,000 daltons. The purified protein interacts strongly with Clq and efficiently activates Cl. RNase and lipolytic enzymes had no effect on the isolated protein but incubation with trypsin resulted in loss of activity. Enzymatic digestion studies of surface-labeled virus indicate that the active protein is a viral membrane protein. On the basis of these results it is concluded that the complement receptor of Moloney leukemia virus is the surface protein p15E.


High levels of secretory IgA and free secretory component in the serum of rats with bile duct obstruction. In the rat , ligation of the bile duct induces a rapid and progressive elevation of the IgA levels in serum. The increase is about 4-fold at 1 h, 15-fold at 1 day, and 30-fold at 1 wk after ligation. The additional IgA is of the secretory type. Free secretory component also appears in serum after bile duct obstruction; it does not continue to increase and occasionally disappears from serum after prolonged ligation. The increase in serum IgA levels is selective. These changes are totally reversible if the bile duct is reopened at 1 day after ligature. These findings confirm the role of the rat liver in the transfer of circulating IgA into the bile.


Prostaglandin E production by human blood monocytes and mouse peritoneal macrophages. Purified populations of both human peripheral blood monocytes and murine peritoneal macrophages synthesize and release Prostaglandin E in vitro. In contrast, prostaglandin E was detected in neither the supernate fluids from cultures of highly enriched human lymphocytes and granulocytes, nor in nonadherent murine peritoneal cells. Macrophage prostaglandin E production was markedly enhanced by endotoxin, and completely suppressed by indomethacin. All neoplastic monocyte-macrophage cell lines examined elaborated prostaglandin E in vitro, either constitutively or after induction with endotoxin. In contrast, prostaglandin E production could not be detected from either a T- or B-cell lymphoma, whether or not they were treated with endotoxin. These findings thus indicate that the blood monocyte and tissue macrophage represent an important source of prostaglandin E, a function shared by both normal and neoplastic mononuclear phagocytes.


Isotachophoretic analysis of serum for aspartic acid, asparagine, glutamic acid and glutamine. Free amino acids and other low molecular weight components were separated from samples of human blood serum by membrane ultrafiltration. The filtrates were analyzed for aspartic acid, asparagine, glutamic acid and glutamine by isotachophoresis, without further treatment. For comparison, analyses were also performed by ion-exchange chromatography. The results of the analyses from both methods are of similar magnitude. General trends were noted in the samples analyzed. The values for aspartic acid and asparagine were lower, by both methods, than normal values. Also, the values, that were determined by isotachophoresis, were generally higher than those obtained from ion-exchange chromatography. The results are sufficient to demonstrate the applicability of the method to the analysis of the two amino acids and their amides in serum.


Chelation of ambilhar with calcium and magnesium. The effects of Ambilhar (niridazole or nitrothiazole) on the calcium, magnesium and phosphorus contents of various tissues of rabbits were studied. It results in a decrease in the calcium content of bones, liver and muscles. A similar depletion of the magnesium content of brain, blood, liver and muscles was observed. On the other hand, the urinary excretion of calcium and magnesium was increased. These facts indicate that the drug possibly chelates with these divalent cations. This is supported by the ultra violet spectra of the complexes prepared in vitro. The effect of Ambilhar on tissue phosphorus seems to be indirect. The phorphorus contents of both blood and urine are decreased. This could be due to an increased calcium concentration. These findings may explain the toxic effects of Ambilhar on the nervous system.


Isoenzymes of N-acetyl-beta-glucosaminidase from human liver and serum: separation by electrofocusing in thin layers of polyacrylamide gel. Isoenzymes of N-acetyl-beta-glucosaminidase can be separated by electrofocusing in thin layers of polyacrylamide gel. Patterns of isoenzymes from human liver tissue and serum show changes in liver diseases. Preliminary results indicate, that N-acetyl-beta-glucosaminidase isoenzyme A is increased in liver tissue from patients with chronic liver diseases in relation to the activity of mesenchyme reaction. The described method will be discussed in comparison with known separation techniques.


Interference with short-term visual memory produced by concurrent central processing. Double-letter memory and test stimuli were used in two experiments on a speek comparison task. Faster decision times were found when memory and test stimuli were physically identical than when they were the same in name only. This finding was true even with retention intervals as long as 12 sec and even when difficult tasks filled the retention intervals. However, the decision-time advantage of physically identical comparisons was greatest when the interval was not filled with a task likely to interfere with rehearsals. High verbal subjects had a smaller advantage for the physically identical comparisons than did low verbal subjects but were affected in the same way as low verbal subjects in terms of which conditions raised the overall correct comparison times, raised the error rates, and reduced the advantage of physically identical comparisons.


Picture-word differences in the acquisition and retention of paired associates. In a study of paired-associate learning and retention, the mode of presentation (pictures versus words) of the stimuli and the responses was varied factorially. The numbers of acquisition trials were adjusted to control degree of learning, and recall was tested 1 week after the end of acquisition. Learning was substantially retarded when pictures rather than words were used as responses. Rate of improvement over trials was faster with pictorial than with verbal stimuli, but these effects were less pronounced than those on the response side. The differences in long-term retention were relatively small. The stimulus mode had no effect; the picture-response ggroups showed some advantage over the word-response groups. Some of the results pose difficulties for current interpretations of picture--word differences.


Visual recognition memory for binary pictures: another look. Recognition memory for matrices of 0s and 1s was examined as a function of the number of elements (complexity) and density of those elements within the matrix. It was found that with greater density and lesser complexity, recognition performance improved. This result contradicts an earlier finding of Green and Purohit, who concluded that the more complicated matrices led to better performance. The present study suggests that their conclusion was erroneous and stemmed from failure to control the physical parameters of density and number of elements in the matrix. Implications for the general problem of recognition memory and eye movements are discussed.


Depth of processing and retention of words by alcoholic Korsakoff patients. The relationship between the depth to which a word is initially processed and its eventual probability of being recognized was investigated with amnesic (alcoholic Korsakoff) patients. Several variations of Craik and Tulving's paradigm designed to asses this relationship were used. basically, this procedure insures analysis of particular features of a word by the nature of the question the subject must answer about the word during its initial presentation. Decision-time measures demonstrated that Korsakoff patients could answer the query nearly as rapidly as normals, but the patients failed to demonstrate a normal increase in recognition as a function of the depth of analysis demanded by the query (Experiments 1--2). However, when the test procedure was extremely simplified (Experiment 3) by presenting only a small number of to-be-recognized words, the Korsakoff patients did demonstrate the normal "pattern" of recognition. It was concluded that under the appropriate circumstances, Korsakoff patients' recognition memory can be improved by instructions to analyze the more sophisticated (semantic) features of verbal information.


Biasing the development of response topography with nonspecific positive and negative evocative verbal stimuli. Conditioned response (CR) rate and development of CR latency, rise time, and airpuff attenuation were examined for V- and C-form responders using two nonspecific command words, do and don't, as conditioned stimuli (CSs) in single-cue, double-cue, and differential eyelid conditioning. In both single-cue and differential conditioning, regardless of the command word used to signal the unconditioned stimulus (UCS), the Vs produced a higher response rate and learned a better UCS-attenuating response topography than the Cs. However, in a double-cue conditioning paradigm in which both command words were presented alone on different trials and reinforced, response latency was longer and puff attenuation poorer among Vs than when the UCS was signaled by a unique cue. In contrast, adding a second reinforced cue actually enhanced the development of puff-avoidant CR topographies among Cs compared to single-cue conditioning. These results and others indicate that response topography development is to some extent a labile process that can be biased toward either good or poor puff-avoidant properties and that the factors responsible for influencing CR topography differ for Vs and Cs.


Cholesterol in preteen children of parents with premature coronary disease. A pediatric population at high risk for the development of coronary artery disease has been identified. Using a simple and inexpensive protocol, serum cholesterol determinations were performed on 50 children 12 years old and younger. These children were taken from 28 families in which one parent had suffered a myocardial infarction before the age of 50. Eight of the 50 children were found to have significant elevation of serum cholesterol. This was an incidence of 16%--twice that of the general pediatric population. Subjects with both adverse genetic and metabolic backgrounds need to be identified in this simple way. Preventive and therapeutic measures in such children may alter in the future the serious morbidity and mortality of coronary artery disease.


Screening in family medicine: the current situation. Unrealistic patient expectations, financial constraints, and lack of medical scientific evidence as to the benefits of screening make it difficult for the family physician to establish appropriate screening procedures in his/her practice. The current status of screening is reviewed and some suggestions are made as to how family physicians might better use what is known about screening.


Mitral valve prolapse in a family practice setting. Mitral valve prolapse (MVP) syndrome is a relatively new clinical entity and fairly commonly encountered in clinical practice. The symptoms are often so vague that it is frequently not diagnosed or misdiagnosed for completely unrelated conditions. The recognition of MVP is important since the symptoms as well as the arrhythmias produced may be responsive to propranolol and the incidence of bacterial endocarditis is known to be increased. This paper reports on 25 patients with MVP in a family practice setting and compares this experience to recent literature on this problem.


Patterns of rape and approaches to care. The family physician is likely to be involved in the care of the rape victim. This paper focuses on the social and legal definitions of rape as well as the incidence of rape. The Rape Trauma Syndrome is explained and normative responses of victims are discussed. Eight common myths about rape are identified which the victim and the physician may share. In discussing the myths, guidelines for counseling the rape victim are delineated: encourage the victim to talk about her feelings; as the physician, remain nonjudgmental; provide information or resources to the victim; view the aftermath of rape as a response to a life-threatening event; and enlist the support of the victim's significant others. Finally, the importance of understanding the available community resources is stressed.


Identification and management of the anxious patient within a model family practice unit. Because anxiety is the third most common problem encountered in this Model Family Practice unit, the presentation and management of 36 randomly selected cases were reviewed. The incidence was not greater in one race, but was increased in all married females (age 25 to 35) who, despite wife or husband working, had a very low income. The foremost complaints were insomnia, headaches, and chest pain with 80% of the patients maintaing the same symptoms. The resident identified a conflict (the most frequent being marital problems) in 47% of the cases. Drug therapy was used in 86.1% with ten percent selected for symptom relief. Because there are times when an alternate to drug therapy is needed, an overview teaching series on brief psychotherapy is suggested as an appropriate part of the behavioral science curriculum in a residency program.


Behavioral medicine in family practice: a unifying approach for the assessment and treatment of psychosocial problems. Assessment and treatment of the varied psychosocial problems which affect patient health often present primary care physicians with their most difficult and frustating problems. This paper outlines criteria which can be used to select a model of psychosocial treatment compatible with an active family practice clinic. It also describes one treatment model which fits the criteria and can be used to assess and treat a wide range of psychosocial problems common to family practice.


Physical diagnosis courses--a question of emphasis. The ability of 12 students to examine hospitalized patients at the end of a course in physical diagnosis was measured through the use of video tapes of patient examinations and audit of written summaries. The results indicate the course in physical diagnosis underemphasized the most important aspect of the patient examination, the patient interview. The errors most often committed by students performing physical examinations and taking histories from patients suggest that increased observation of students by preceptors would be profitable in improving the course. Course evaluation through video taping of actual student examinations proved highly instructive and useful in developing a more effective program.


Teaching geriatric care: report on an experimental second-year elective. To help fill the growing need for medical school instruction in geriatric care, the Departments of Family Medicine and Community Medicine at the College of Medicine and Dentistry of New Jersey-Rutgers Medical School, in cooperation with Roosevelt Hospital, a nearby county-supported chronic disease facility, joined to develop an experimental second-year elective, given for the first time in the fall of 1976. The curriculum involved 11 three-hour sessions covering a variety of medical and socioeconomic topics. Enrollment was limited to 12 students. Reaction was positive on the part of students, patients, and faculty, especially with respect to student attitudes toward the elderly. Improvements are suggested in six major areas.


Psychosocial factors seen as problems by family practice residents and their spouses. Residents and spouses in the University of Minnesota Family Practice Program were surveyed using an inventory relating to psychosocial stresses in their lives. Faculty realized that the residency period of education was a process of critical role transition. Adequate adaptation made to stresses is related to the learning environment. The survey revealed that central concerns are leisure/time scarcity problems, domestic/spouse complaints, conflicting demands on study needs, lack of self confidence, reservations about medicine as a career choice, decrease in sexual expression, parenting worries, and communication deficiencies. Empirical data on stresses give rise to some program modifications and to further research.


Maximizing patient compliance by shaping attitudes of self-directed health care. Research studies consistently find that a large proportion of patients do not comply with physicians' recommendations. Consequences of such high noncompliance on the efficiency and effectiveness of health-care delivery systems are dramatic and obvious. Recognition of this problem was the impetus for beginning this patient compliance study. Key factors involved in maximizing patient compliance were identified and incorporated into a procedure which patients in the experimental group experienced. Patients in the control group experienced. Patients in the control group experienced no special treatment. Compliance rates were higher for the experimental group; however, compliance rates in both control and experimental groups tended to be higher than cited in the literature. It was founded that patients in the experimental group seemed to react more favorably to the personal interaction they received as part of the procedure than to other facets of the procedure. Findings of the study imply that increased compliance may be the end result if greater emphasis is placed on building a partnership with the patient rather than making compliance itself a major goal.


Patient education and multiphasic screening: it can change behavior. Two hundred ninety-two residents of Sonoma County, California, underwent multiphasic screeening and two sessions of group patient education aimed at reducing risk factors for cardiovascular disease, cancer, and automobile accidents. Approximately one year later all the participants were retested. A significant reduction was noted in systolic blood pressure in men and women, ages 50 to 70, cholesterol in men over age 40, and reported alcohol consumption in men. A significant increase was noted in the reported frequency of monthly breast self-examination in women, and in the amount of exercise and percentage of time seat belts were used in both sexes. No change was noted in reported amount of cigarette smoking, weight, fasting blood glucose, and triglycerides. The combined use of health hazard appraisal, multiphasic screening, and patient education can lead to a reduction in cardiac and other risk factors in well-motivated groups.


Labstand: a computerized system for reporting clinical laboratory data in standard units. A computerized system, Labstand, is described which was developed to simplify the presentation of laboratory data for the clinician. It converts data into standard units (su) on a scale of 0 to 100, identical for all tests. Conversions are based on both normal and abnormal ranges, determined from clinical experience, to allow both immediate recognition of abnormality and estimation of the degree of abnormality. This paper reports the findings of a study using this system which involved 1,412 abnormal laboratory results. Overall, both recognition and follow-up rates were higher when Labstand was used, but not to a statistically significant level. However, significantly higher follow-up rates were found when Labstand was used by residents with lower than average Internal Medicine National Board scores. In contrast, follow-up was higher when normal range laboratory reports were used by residents with higher than average scores. These findings seem consistent with the fact that use of Labstand requires minimal knowledge of ranges and biological measurement units and may indicate that the lower scoring residents have a greater need for such a new system than do the higher scoring residents.


Tube thoracostomy.

Tube thoracostomy. Every primary care physician should be familiar with three methods of draining fluid or air from the pleural cavity. These methods are: (1) the insertion of a needle or Intracath catheter into the pleural space; (2) a tube thoracostomy using a Trocar catheter; and (3) a tube thoracostomy using a large intercostal tube. Complete anesthesia can be obtained with lidocaine, remembering that the intercostal nerve runs on the undersurface of the rib above. The Intracath catheter for removal of air is inserted in the second interspace anteriorally. The tube thoracostomy, using the Trocar catheter, is best done through the fourth interspace in the anterior axillary line but can be done wherever the exploratory needle shows the major fluid and air collection to be. The tube thoracostomy, using a large intercostal tube, is best done through the fourth intercostal space at the anterior axillary line. The intercostal catheter or tube should be fixed to the chest wall with sutures and then led to an underwater seal for collection of the contents of the pleural cavity.


Management of natal teeth.

Management of natal teeth. 1. Obtain dental radiographs whenever possible before removing natal teeth in order to better advise the parents of complications. 2. Leave natal teeth in the mouth as long as possible in order to decrease the likelihood of removing permanent tooth buds with the natal tooth. 3. Obtain the parents' consent and rule out neonatal hypoprothrombinemia before removing natal teeth. 4. Recommend postoperative evaluation by a pedodontist in order to obtain diagnostic radiographs and necessary treatment.


Chromosome mapping in Acinetobacter calcoaceticus. RP4-mediated conjugation was used to map the loci of 23 different mutations on a circular linkage group in Acinetobacter calcoaceticus EBF65/65. The resulting genetic map indicated that the chromosomal organization of A. calcoaceticus differed from that of members of the enteric group of bacteria and was similar to Pseudomonas in showing an absence of clustering of functionally related genes.


Isolation of extrachromosomal deoxyribonucleic acids from extremely thermophilic bacteria. Eight strains of thermophilic bacteria were examined for the presence of covalently closed circular deoxyribonucleic acid molecules by caesium chloride-ethidium bromide density gradient centrifugation. Four of the eight strains tested, Thermus flavus BS1, AT61, AT62 and Thermus thermophilus HB8 carried covalently closed circular DNA molecules. Thermus flavus BS1 haboured two species of plasmids with molecular weights of 6.1 X 10(6) and 17.0 X 10(6) as determined by electron microscopy. Thermus thermophilus HB8, T. flavus AT61 and T. flavus AT62 carried plasmids with molecular weights of 6.2 X 10(6), 6.6 X 10(6) and 6.6 X 10(6), respectively. Plasmids from T. flavus AT61 and AT62 were indistinguishable in their electrophoretic patterns in agarose or acrylamide gel after digestion with various restriction endonucleases. This is the first evidence for the presence of plasmids in extremely thermophilic bacteria, though their functions are unknown.


Suppression of pathogenicity by P and V plasmids in Vibrio cholerae. In experimental models of cholera, some strains of Vibrio cholerae harbouring P or V or both plasmids were markedly less pathogenic than isogenic strains devoid of these plasmids. This effect was due to decreased production of toxin by P+, V+ or P+V+ bacteria compared with their parents.


Taxonomy and epidemiology of gram-negative bacterial plasmids studied by DNA-DNA filter hybridization in formamide. Phylogenetic and epidemiological relatedness among transferable plasmids belonging to the IncC, IncM and IncH incompatibility groups has been studied by DNA-DNA filter hydridization. Hybridization was carried out on nitrocellulose microfilters, at low temperature, in formamide and under paraffin oil. The degree of hybridization among plasmids belonging to the IncC and IncM groups supported the conclusions drawn from genetic classification. Studies on relatedness among plasmids belonging to the IncH group allowed their classification into three phylogenetic sub-groups. Comparison of DNA sequences of three plasmids sharing the same genetic properties and isolated from different bacterial species suggested an epidemiological spread of the same plasmid.


4,9-Dihydroxyphenazine-1,6-dicarboxylic acid dimethylester and the 'missing link' in phenazine biosynthesis. 4,9-Dihydroxyphenazine-1,6-dicarboxylic acid dimethylester, the ester form of a proposed 'missing link' in the biosynthesis of phenazines, has been isolated from a strain of Pseudomonas cepacia.


Antibiotic production by dermatophyte fungi. Thirty-two clinical isolates of anthropophlic dermatophytes were examined for their capacity to produce antibiotics in liquid culture and on human stratum corneum in vitro. Antibiotics were detected and classified using agar diffusion bioassays and chromatographic analysis. Twenty-four isolates produced antibiotic substances in liquid culture filtrates; some strains produced more than one antibiotic. Only four isolates produced detectable levels of antibiotics when grown on stratum corneum unless an artificial sweat mixture was used as a nutrient supplement, when the number rose 11. Respresentatives of all species studied produced benzyl penicillin-like substances. Some Trichophyton isolates also produced streptomycin-like antibiotics, a characteristic previously unrecorded for eukaryotic organisms. Other antibiotics, which apart from azalomycin F could not be properly classified, were produced by Epidermophyton floccosum. Antibiotic production occurred over the normal skin temperature range but sometimes the type of antibiotic produced and the frequency of detection appeared to be influenced by the incubation temperature.


Resistance of selected saprobic and zoopathogenic fungi to cycloheximide. Spore germination was used as an assay to measure the sensitivities of selected fungi (Achlya bisexualis, Cladosporium sp., Trichophyton mentagrophytes and Microsporum gypseum) to cyclohexamide and to determine their abilities to adapt to the drug. Two patterns of response were noted. The saprobes, A. bisexualis and Cladosporium sp., demonstrated acquired resistance. Spores from hyphae previously exposed to cycloheximide either germinated in the presence of concentrations of the drug that completely inhibited spores from unexposed hyphae (Achlya), or germinates with a shorter lag and to a greater extent in the presence of the antibiotic than did spores from unexposed hyphae (Cladosporium). Hyphae of Achlya adapted at concentrations of cycloheximide in which spores did not germinate and hyphae of Cladosporium adapted more rapidly than spores. Achlya adapted to only 12 muM-cycloheximide whereas Cladosporium acquired resistance to 18 mM-cycloheximide. These fungi lost this acquired resistance after a single transfer to media lacking cycloheximide. The zoopathogens, T. mentagrophytes and M. gypseum, had a contrasting response, indicating constitutive resistance. Conidia from unexposed hyphae showed 90 to 100% germination on media containing up to 18 mM-cycloheximide; prior exposure to the drug did not affect their response.


Purification of the extracellular opacity factor of a strain of group A Streptococcus M type 2. The extracellular Opacity Factor elaborated by a strain of group A streptococcus M type 2 was purified by ammonium sulphate precipitation, DEAE-cellulose and hydroxylapatite column chromatography and Sephadex G-200 gel filtration. Gel filtration experiments indicated that the Opacity Factor is consituted of high molecular weight proteins or protein aggregates which appear to dissociate into subunits of 66000 minimum molecular weight as determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The purified preparations had no group A carbohydrate of T protein antigens. Passive haemagglutination and indirect immunofluorescence tests indicated that Opacity Factor is distinct from the M type 2 protein antigen.


Failure of antibody to e antigen to precipitate Dane particles containing DNA polymerase activity and hepatitis B core antigen. Serum samples of 67 asymptomatic carriers were tested for Dane particles by electron microscopy, and for e antigen by immunodiffusion, as well as for hepatitis B antigen-associated DNA polymerase activity, and four samples enriched with respect to Dane particles were selected. Hepatitis B antigen particles in them were separated from e antigen and concentrated by centrifugation, and the Dane-rich preparations were incubated with buffer, antibody to e antigen (anti-HBe) or antibody to hepatitis B surface antigen. After centrifugation, the supernatant was tested for DNA polymerase activity, and both supernatant and precipitate were tested for hepatitis B core antigen (HBcAg) by the immune adherence haemagglutination method after the coat of the Dane particles had been disrupted with NP-40 and 2-mercaptoethanol. It was found that anti-HBe did not precipitate Dane particles as measured by DNA polymerase activity and HBcAg. On the basis of the results obtained, it has been concluded that e antigen does not exist on the surface of hepatitis B virions.


Regulation of the synthesis of Sindbis virus-specified RNA: role of the virion core protein. Cells infected with seven different RNA+ mutants of Sindbis virus were found to accumulate a virus-specified polypeptide of mol. wt. 144000 (p144) during incubation at the non-permissive temperature, while at the same time synthesis of the virus structural proteins was drastically reduced. Mapping of the tryptic peptides of p144 showed that it contained the amino acid sequences of all the virus structural proteins. At the non-permissive temperature cells infected with the same seven mutants (out of 28 examined) also showed increased synthesis of 26S RNA, the mRNA for the virus structural proteins, relative to 42S RNA, and the virus genome, compared with infections by wild-type virus. We propose that both these phenotypic effects are the results of a single mutational step and that the primary defect in the processing of the virus structural protein precursor induces the relatively increased rate of synthesis of structural protein mRNA. Temperature-shift experiments with mutant-infected cells showed that p144 itself is not the agent of this effect. The failure of exposure to zinc ions to alter the RNA ratio in wild-type virus-infected cells suggested that the virus envelope proteins are not involved either, since their synthesis is preferentially inhibited under these circumstances. It is possible that it is the failure to synthesize the proper quantity of core protein in the mutant-infected cells which causes the shift of RNA synthesis in favour of structural protein mRNA.


Radioimmunoassay and some properties of human antibodies to hepatitis B core antigen. A solid-phase radioimmunoassay for antibodies to hepatitis B core antigen (anti-HBc) is described. Polystyrene beads coated with anti-HBc, hepatitis B core antigen prepared from pooled sera of humans infected with hepatitis B virus (HBV) and 125I-labelled anti-HBc were used for the test. Distinct patterns of development and changes of anti-HBc and their immunologic properties are all related to variations of other markers specific for HBV infections. Knowledge concerning the detailed features of the immune response to hepatitis B core antigen may provide deeper insight into the pathogenesis of HBV infections.


Fast-axon synapses of a crab leg muscle. Neuromuscular synapses of the "fast" excitatory axon supplying the main extensor muscle in the leg of the shore crab Pachygrapsus crassipes were studied with electrophysiological and electron-microscopic techniques. Electrical recording showed that many muscle fibers of the central region of the extensor muscle responded only to stimulation of the fast axon, and electron microscopy revealed many unitary subterminal axon branches. Maintained stimulation, even at a low frequency, resulted in depression of the excitatory junctional potentials (EJPs) set up by the fast axon but EJPs of different muscle fibers depressed at different rates, indicating some physiological heterogeneity among the fast-axon synapses. Focal recording at individual synaptic sites on the surfaces of the muscle fibers showed quantal contents ranging from 1.4 to 5.5 at different synapses; these values are relatively high in comparison with similar determinations made in the crayfish opener muscle. Synapse-bearing nerve terminals were generally relatively small in diameter and filiform, with many individual synaptic contact areas of uniform size averaging 0.6 micron2. All of the individual synapses had a presynaptic "dense body" at which synaptic vesicles clustered. If these structures represent release points for transmitter quanta, the initial high quantal content would have an ultrastructural basis. The mitochondial content of the nerve terminals, the synaptic vesicle population, and the specialized subsynaptic sarcoplasm were all much reduced in comparison with tonic axon synaptic regions in this and other crustaceans. The latter features may be correlated with the relatively infrequent use of this axon by the animal, and with rapid fatigue.


Nonhomogeneous excitatory synapses of a crab stomach muscle. Neuromuscular synapses of pyloric muscle P1 in the blue crab Callinectes sapidus were examined using electrophysiological and electron microscopic methods. The muscle is innervated by a single excitatory axon of the stomatogastric ganglion. Excitatory postsynaptic potentials show striking facilitation at very low frequencies of stimulation, indicating very slow decay of the facilitation process after a single nerve impulse. Quantal content of transmitter release at a low frequency of stimulation averaged 1.5. Evidence was obtained that not all synapses on a muscle fiber are equivalent. This was particularly evident at the morphological level in serially sectioned nerve terminals. On each nerve terminal examined, a wide range of synapse sizes was found. Synaptic contact areas ranged from less than 0.5 micron2 to almost 10 micron2; the latter value is large compared with those obtained for other crustacean neuromuscular synapses. Most of the smaller synapses lacked the presynaptic dense bodies which are putative release sites for the transmitter substance. The larger synapses all had presynaptic dense bodies, and some showed evidence of splitting apart into smaller subunits. It is postulated that about half the morphologically identified synapses are relatively inactive.


The effect of amino acids on protein metabolism as measured in long-term experiments in immature brain explants. In a study of a system suitable for investigating long-term effects on brain protein metabolism, we measured amino-acid incorpration into isolated immature brain explants incubated under sterile conditions up to ten days. Measurements of changes in total proteins, total DNA, cell number during the experiments, and 14C-thymidine incorporation measurements indicated no significant net growth; new cell formation was below 5% in a 5-day period; therefore, amino-acid incorporation was mainly due to protein turnover. The rate of incorporation in our immature brain preparation was similar to that of the adult brain in vivo: by ten days about one-half of the tissue protein turned over. The label incorporated was released in subsequent incubations with cold amino acids. Such release occurred in all subcellular fractions examined. Incorporation was fairly stable; at temperatures below 30 degrees C it rapidly declined, but it was not affected when phenylalanine or the branched chain amino acids (leucine, isoleucine, valine) were elevated in the incubation medium. Brief exposure to low amino-acid media had no effect; longer exposure resulted in tissue damage. Our model system indicates that overall brain protein turnover is not sensitive to such variations in the level of most amino acids, which may occur under various conditions. Protein metabolism of the nervous system occurs at a high rate. A recent long-term labeling method (Lajtha, Latzkovits, and Toth, 1976) gave a best fit to incorporation curves by assuming two compartments for adult brain proteins, one of which (about 6%) has a half-life of 15 hr and the other (94%) has a half-life of ten days. The disappearance of protein-bound label with time under conditions in which all proteins were previously labeled indicated that most, possibly all, proteins in brain are in a dynamic state (Lajtha and Toth, 1966). Incorporation of amino acids was found in all proteins and structures that have been studied to date; myelin proteins previously thought less active are also metabolized at a significant rate (Sabri, Bone, and Davison, 1974; Lajtha, Toth, Fujimoto, and Agrawal, 1977). We have fairly extensive information available in addition to turnover studies about the mechanisms of protein synthesis in brain (Roberts, 1971); protein breakdown was also studied in some detail (Marks and Lajtha, 1971). In contrast to our knowledge about protein metabolism under physiological equilibrium conditions, our information about alterations during functional demands or pathological conditions is scanty. Although a significant amount of work has been reported, largely because of technical difficulties the results are difficult to interpret unequivocally. The present report represents our effort to address some of the obstacles: to develop a system in which influences on long-term incorporation can be studied...


The dorsal, unpaired, median neurons of the locust metathoracic ganglion. Neurons having large cell bodies in the anterior dorsal median cluster in the metathoracic ganglion of the locust Schistocerca gregaria and the grasshopper Romalea microptera were studied by direct dye injection and reverse filling combined with elyctrical stimulation and recording. Eight, possibly nine, are of the unpaired type, with a T branch leading into left and right axons that leave the ganglion to terminate in muscles. Another six are probably paired, and may be interneurons. Five of the 8 or 9 unpaired neurons have one axonal branch in both N4 and N5, on both sides: the others have but a single branch. One of the nine, DUMETi, has left and right axons exclusively innervating the jumping muscles, and another, DUMDL, has left and right axons exclusively innervating the dorsal longitudinal flight muscles. Neither the locations, sizes or numbers of somata, nor their locations were as constant as is the case for ordinary ventral motoneurons.


Clinical significance of plasma adrenaline and noradrenaline concentrations in patients with subarachnoid haemorrhage. Plasma adrenaline and noradrenaline concentrations were measured in 21 patients after subarachnoid haemorrhage and in 13 control patients. Plasma noradrenaline concentrations were significantly raised in patients recovering from subarachnoid haemorrhage, confirming clinical evidence of overactivity of the sympathetic nervous system. Plasma noradrenaline concentrations in patients with a poor result were significantly higher at the time of admission than in patients with a good result, and the differences became more significant two to three days later. Therefore, the measurement of plasma noradrenaline concentrations may be a valuable test to assist clinical assessment in distinguishing between the two groups preoperatively.


Platelet adhesiveness, plasma fibrinogen, and fibrinolytic activity in young patients with ischaemic stroke. Cerebral thromboembolic stroke in the young is uncommon. Disturbances in the n ormally existing dynamic equilibrium between coagulation and fibrinolysis may play a major role in the pathogenesis of such episodes. In a search for a possible hypercoagulable state platelet adhesiveness by the method of Eastham, plasma fibrinogen and euglobulin clot lysis times were estimated in 46 patients. A group of 15 normal subjects matched for age and sex were also studied for comparison. Significant increase in platelet adhesiveness (P less than 0.001) and plasma fibrinogen (P less than 0.001) was noted in the patients when compared with the normal subjects. Absence of corresponding increases in fibrinolytic activity in the patients suggests disturbed equilibrium between coagulation and fibrinolysis. The possibility of a hypercoagulable state in these cases is discussed.


Correlation between angiographic findings and the ischaemia of head injury. The carotid angiograms of 96 patients who had died from non-missile head injury were reviewed and assessed for evidence of arterial spasm, slowing of the cerebral circulation, and the presence of intracranial haemotoma. As bilateral angiography had been done in 44 cases the results are based on a correlation between the angiographic appearances and the presence or absence of ischaemic brain damage in the cortex of 140 cerebral hemispheres. There was a significant relationship between spasm alone, the presence of intracranial haematoma alone, or their combination, and ischaemic damage in the ipsilateral cortex. Apart from an association between the more severe grades of spasm and slowing of circulation in the group with ischaemia within arterial territories, there was none between slowing of the circulation or the combination of slowing with either spasm or haematoma and ischaemic brain damage.


A quantitative electrophysiological study of uraemic neuropathy. Diabetic and renal neuropathies compared. The numbers of functioning motor units and the parameters of the electrically evoked motor unit potentials in the extensor digitorum brevis muscles of 30 patients on chronic haemodialysis for renal failure were obtained using recently introduced quantitative electrophysiological techniques. Measurements of the distal motor latencies and motor nerve conduction velocities in the lateral popliteal nerves of the same patients are also presented. The results support the presence of a "dying back" type of neuropathy in uraemia, with a preferential involvement of the fastest conducting motor axons. Collateral reinnervation and compensatory increase in size of surviving motor units is relatively impaired in uraemic neuropathy in comparison with a similar study on diabetic neuropathy. The significance of paranodal and segmental demyelination in producing abnormalities of conduction velocity in these neuropathies is discussed.


Progressive myoclonus and epilepsy with dentatorubral degeneration: a clinicopathological study of the Ramsay Hunt syndrome. Ramsay Hunt's progressive myoclonus and epilepsy associated with dentatorubral degeneration is a rare disorder. We report a 19 year old woman with this clinical syndrome who also has a more mildly affected brother. Neuropathological in addition to dentatorubal involvement. The evidence suggests that this is a distinctive hereditary disorder producing neuromal degeneration at several levels in the central nervous system.


Schwartz-Jampel syndrome in two daughters of first cousins. The clinical and pathological features of two sisters born from consanguineous parents and affected by the rare Schwartz-Jampel syndrome are reported. The parental consanguinity of these two patients and the findings of electromyographic changes in the mother strongly support an autosomal recessive pattern of inheritance. No response of growth hormone secretion to arginine and insulin stimulation tests was found.


Anatomical observations of the foramina transversaria. Four hundred and eighty foramina transversaria in dry cervical vertebrae of 36 spines and in a number of dissections were studied and classified according to size, shape, and direction of their main diameter. A coefficient of roundness was then elaborated. The variations of foramina appear to follow a pattern at various vertebral levels. The possible factors (in addition to the embryological ones) involved in causing these variations-for example, mechanical stress, size, course, and number of vertebral vessels-were analysed. The importance of the correct interpretation of the variations in the foramina transversaria in radiographic or computerised axial tomography is discussed. The contribution of the present study to the understanding and diagnosis of pathological conditions related to the vertebral artery and its sympathetic plexus is stressed.


The changing pattern of spinal arachnoiditis. Spinal arachnoiditis is a rare condition. Eighty cases, diagnosed during a period when 7600 spinal contrast investigations were undertaken, have been reviewed. The majority had suffered a previous spinal condition, the most common being lumbar disc disease. There has been a change in the distribution of arahnoiditis with the lumbar region now most frequently involved. This accounts for the persistence of radicular symptoms and the relatively low incidence of paraplegia when compared with earlier series. Surgery does not appear to have any role in the treatment.


Electroencephalography and phenytoin toxicity in mentally retarded epileptic patients. There were significantly more diffuse and focal electroencephalographic abnormalities in 127 mentally retarded epileptic patients treated with phenytoin than in 68 epileptics without phenytoin. Phenytoin intoxication made the difference still more pronounced. Monitoring drug levels and electroencephalograms appears to be the method of choice for ensuring safe and effective medication in intractable epilepsy.


Patterns of performance in amnesic subjects. Patients with Korsakoff's syndrome, dementia, alcoholism, right and left temporal lobectomy, and normal subjects were compared on verbal learning and picture recognition memory tasks. Alcoholics and right lobectomy patients were similar on all measures, but the other groups had a characteristic pattern, particularly on hit and false positive rates in picture recognition.


Conservative removal of small pituitary tumours: is it justified by the pathological findings? Operation by the trans-sphenoidal route allows removal of small pituitary adenomata with conservation of normal gland. Histological examination of tissue obtained at operation and necropsy in 73 cases showed that surgical methods at present in use are likely to leave tumour behind in the pituitary gland and in the dura mater of the pituitary fossa. The clinical significance of these findings will only become evident after following patients for an extended period, but there appears to be a strong indication for routine postoperative radiotherapy.


Schwartz-Jampel syndrome. Clinical, electrophysiological and histopathological study of a severe variant. This report describes a child, offspring of a first cousin marriage, with a severe and progressive disorder of bone and cartilage growth associated with a myotonia-like syndrome. Clinical manifestations of this disease began at birth with marked generalized muscle hypertrophy, stiffness, myotonia and multiple skeletal deformities. Successively severe dwarfism and mental retardation were observed. Neurophysiological studies showed continuous high frequently low voltage activity at rest and myotonic discharges which did not wax and wane. These abnormalities persisted after complete curarization. Muscle biopsy showed mild dystrophic changes. Polymeric glycosaminoglycans and degradation product excretion was normal. These findings are similar to those described in Schwartz-Jampel syndrome, but since the clinical picture was fully expressed at birth and was unusually severe, it is suggested that the patient's condition may have represented a severe variant of this syndrome.


Disuse atrophy of skeletal muscle. A morphometric study using image analysis. A morphometric study of disuse atrophy was done on the rat anterior tibilalis muscle over a 13-day period after immobilization of the hind leg by pinning the knee and ankle joints. Cross-sectional areas of individual muscle fibers were measured using image analysis, a new and precise technique. Three types of muscle fibers, light, medium and dark, were defined using a modified myosin-ATPase reaction on cryostat-cut sections. Each of  the 3 fiber types was found to show a degree and time course of atrophy unique to itself. At the 0.01 confidence level, the dark fibers (with strongest ATPase reaction) did not shrink significantly. Both the light (ATPase negative) and medium fiber did show significant atrophy at that level; the light shrinking more than the medium. Simple visualization of the light microscopic images was often found to be misleading. Thus, the need was documented for a precise technique for analysis of fiber size distribution.


Further studies of mitochondrial and lipid storage myopathies. Further observations on a family with facioscapulohumeral (FSH) muscular dystrophy due to mitochondrial myopathy, and on a case with lipid storage myopathy are reported. One member of the family with FSH muscular dystrophy died due to a viral pneumonia, during which she developed gross hyperlacticacidaemia and acidosis. Autopsy examination showed that the mitochondrial morphological abnormality was restricted to the skeletal muscle. Two other members of the family, who also had mitochondrial myopathy, have developed a cerebellar syndrome. The skeletal muscle carnitine level in the propositus of this family was normal. A woman with lipid storage myopathy has been shown to have skeletal muscle carnitine deficiency, the plasma carnitine level being only slightly lower than normal.


The cervical somatosensory evoked potential (SEP) in the diagnosis of multiple sclerosis. Abnormalities of the potential evoked by stimulation of the median nerve and recorded over the cervical spine were found in 59% of patients with multiple sclerosis (MS) this proportion increasing to 69% of those in the definite diagnosis category and to 100% in the severely disabled. Abnormalities were often found in the absence of relevant clinical signs and the method appears to be capable of revealing clinically silent plaques. In patients with a single episode of neurological disease, including retrobulbar neuritis, and at least compatible with the onset of MS, the proportion of abnormalities did not rise above 18%. Only prolonged follow-up will permit assessment of the value of this and other evoked potential techniques in the detection of the early case of the disease.


Demyelination of Sternarchus electrocyte fibers by injection of diphtheria toxin. Diphtheria toxin was injected into the electric organ of the gymnotid fish, Sternarchus albifrons. After 10 days, there was extensive demeylination of electrocyte fibers in the area of injection. Electron microscopy showed that paranodal loops of myelin do not separately cleanly from the axon, and remnants of the myelin loops may persist after demyelination of the internodes is nearly complete. The dense cytoplasmic undercoating of the nodal axolemma may disappear before the paranodal junctions are completely gone. Observations of demyelination of internodes between the elaborate, inexcitable nodes suggest that the presence of myelin may not be necessary for the maintenance of structural differentiation of this region of the axolemma. Use of diphtheria toxin to demyelinate Sternarchus electrocytes may provide a useful system for experimental neuropathological studies.


Porphyric polyneuropathy and its pathogenesis in the light of electrophysiological investigations. Twenty-four patients with acute intermittent porphyria were examined by means of routine electromyographic (EMG) tests, measurements of motor and sensory conduction in peripheral nerves and stimulation fatigue tests. The EMG results gave evidence of an initial, reversible disorder of function of the peripheral neuron, only sometimes followed by evidence of axonal degeneration of the "dying back" type. In stimulation fatigue tests there was some evidence of potentiation but none of fatigue. Attention is drawn to some analogies between the electrophysiological changes in porphyric polyneuropathy and in botulism. It seems that the pathogenesis of porphyric polyneuropathy may be dependent upon a block of cholinergic endings.


Freeze-fracturing studies of mitochondrial myopathy. A correlated clinical, biochemical and morphological investigation. Freeze-fracture studies of pathologically changed mitochondria in situ from muscle biopsies of a 9.5-year-old girl with a mitochondrial myopathy were correlated with clinical, biochemical and histochemical investigations. In the ultrathin sections giant mitochondria with densely packed cristae membranes - often reoriented to concentric circles - and, in addition, paracrystalline mitochondrial inclusions were found. The freeze fracture faces of such transformed mitochondria and preparations of their inner and outer membranes provided a morphological insight in the macromolecular structure of the mitochondrial membrane under such pathological conditions. The results lead to the hypothesis that part of the transformed mitochondria stay active functionally for an extended period by maintaining the delimitation from the cytoplasm and by preserving the macromolecular membrane architecture. This hypothesis could explain the slow progression of the myogenic symptoms.


Reduction by linoleic acid of the severity of experimental allergic encephalomyelitis in the guinea pig. This paper reports the effects of supplementation of the diet with linoleic acid on the severity of experimental allergic encephalomyelitis (EAE) in guinea pigs. Clinical signs of disease (e.g. paresis, paraplegia, urinary incontinence), weight loss, frequency of perivascular lesions in the central nervous system and ability of isolated lymph node cells to respond to myelin basic protein in vitro were all reduced by linoleic acid supplementation. Linoleic acid was effective when fed at a dose of 0.5 ml/day from 7 to 21 days after sensitization of the animals with basic protein, i.e., before and during the time in which clinical signs normally appeared. The same daily dose fed from 7 days before to 7 days after sensitization, i.e., ceasing about 7 days before the normal time of appearance of clinical signs, produced no significant effect. Feeding linoleic acid to normal guinea pigs significantly altered the fatty acid composition of their serum and lymph nodes, but not of their brain. Of several possible explantations for the protective effect of lineolic acid in EAE, we considered action by this essential fatty acid on the immune system most likely.


[Quantitative study of isolated nerve fibers in alcoholic neuropathy (author's transl)]. This is a report of qualitative and quantitative study of nerve fibres in alcoholic neuropathy. In order to determine the frequency of segmental demyelination in alcoholic neuropathy, 10 nerve biopsies from 9 patients were studied by teasing; 100 consecutive fibres were isolated from each nerve and classified according to their morphology. This study confirms that segmental demyelination is a rare finding in this condition. Segmental demyelination of peripheral nerve fibres occurred in three cases and affected 6 to 8 per cent of the fibres. Wallerian degeneration of nerve fibres was found in all ten nerve biopsy specimens and affected 31 to 98 percent of the isolated fibres.


Neural spread of herpes simplex virus types 1 and 2 in mice after corneal or subcutaneous (footpad) inoculation. Twelve herpes simplex virus (HSV) strains, 6 of each type, were inoculated subcutaneously into the left hind foot and into the cornea of the right eye of 12-day-old Swiss albino mice. The neural spread of virus to trigeminal and spinal ganglia and to brain and spinal cord was studied by demonstration of infective virus, histology and electron microscopy. Type 1 and type 2 infections seemed to spread equally well by intra-axonal transport. Using a protein tracer (horseradish peroxidase) injected into the same site as the virus, transport of the tracer to neurons corresponding to those infected with virus was observed. The extensive destruction of CNS tissue in the transitional region of the trigeminal root where CNS and the peripheral nervous system meet is discussed with reference to the pathogenesis of HSV encephalitis.


Cerebral cysticercosis.

Cerebral cysticercosis. Twenty cases of cysticerosis involving the central nervous system were seen during a 6-year period. Twelve patients presented with symptom and signs of raised intracranial pressure, 6 with seizures and 1 each with subacute meningitis and psychosis. The diagnosis of cerebral cysticercosis was established by brain biopsy in 8 patients, at autopsy in 3, and by biopsy of a subcutaneous nodule in 7. It was presumed on the basis of typical intracranial calcification in 1 case and soft tissue calcification in another. The protean clinical manifestations of this condition and the diagnostic difficulties it raises are discussed.


Herpes simplex virus antibodies in patients with Parkinson's disease. Sera from 40 patients with idiopathic Parkinson's disease and their age- and sex-matched controls were assayed for immunoglobulin G (IgG) antibodies against herpes simplex virus (HSV) type 1-induced cell surface antigens with the indirect immunofluorescent test. An increased level of HSV antibodies was found among the patients with Parkinson's disease when the distribution of titres (P less than 0.001), the mean titres (P less than 0.001), or the mean paired titre difference (P less than 0.001) was compared with the controls. This may suggest a part of HSV in the pathogenesis of Parkinson's disease. Alternatively, the increased HSV antibody response might be an epiphenomenon indirectly associated with Parkinson's disease.


14-3-2 protein in rat brain.

14-3-2 protein in rat brain. The distribution of the 14-3-2 protein in rat brain was investigated by immuno-electron microscopy using antiserum to the protein conjugated with peroxidase. 14-3-2 was demonstrated in the nuclear membrane, the endoplasmic reticular membranes and in the plasma membrane of nerve cells. The protein was also localized to the presynaptic densities and to the pre- and postsynaptic membranes. It could not be demonstrated in the membranes of the Golgi complex, inner membrane of mitochondria or in the nucleoplasm of neurons. No 14-3-2 protein was found in astrocytes, oligodendrocytes or in non-neuroectodermal tissue elements.


Atypical progressive multifocal leukoencephalopathy and primary cerebral malignant lymphoma. Atypical progressive multifocal leukoencephalopathy occurred in an 82-year-old man with long-standing chronic lymphocytic leukemia. The multifocal white matter lesions revealed demyelination and gliosis, relative preservation of axons and a prominent plasma cell infiltrate. Bizarre astrocytes were uncommon. There were no changes in the oligodendroglial nuclei and no inclusion bodies. Electron and immunohistofluorescence microscopy for papova virus were negative. In addition to this leukoencephalopathy a small primary cerebral lymphoma was present in the right occipital lobe. The tumor cells were plasmacytoid in appearance and their cytoplasm stained well with pyronin. They contained IgG by immunohistofluorescence microscopy. The neoplasm was considered an immunoblastic sarcoma (reticulum cell sarcoma) and thought to arise directly within foci of demyelination. Both disease processes, leukoencephalopathy and lymphoma, may have occurred on a background of immunosuppression.


The cytogenetic basis for classifying ependymomas. The phylogeny of ependymal cells and astrocytes can be traced to a single primitive progenitor the ependymoglia or the tanycyte, respectively. Ependymoglia cells have ependymal perikarya having astrocyte-like processes that terminate subpially in primitive glial footplates. Such cells prevail in primitive nervous systems, but they also persist regionally in the mature mammalian brain. Their fine structure has been studied in many species. An electronmicroscopic study of 8 ependymomas reveals that the neoplastic cells possess features characteristic of primitive ependymoglia; in particular they possess cell processes filled with glial filaments, terminating submesenchymally in a primitive, piston-shaped footplate. The perivascular pseudorosettes of ependymomas are the equivalents of these cell poles. The dominant phenomenon of ependymoma structure appears to be a reversion of cellular organization to the stage of primitive ependymoglia cells. On reviewing 43 ependymomas and 71 astrocytomas 11 neoplasms were found having a tissue structure reminiscent of the evolution of piloid astrocytes from ependymoglia or tanycytes, respectively. These features correspond to transitional stages seen in normal primitive brains. Tumors of this type may be characterized as a tanycytic variant of ependymomas. They appear to be relatively common in the spinal cord and present a source of confusion with piloid astrocytomas.


Substance P-like immunoreactivity in cultured spinal ganglia from chick embryos. The localization of substance P (SP) or a SP-like peptide in cultured ganglia from chick embryos was studied by the indirect immunofluorescence technique. Ganglia from 8-16 days old chick embryos and from newly hatched chickens were cultured in a control medium or in the presence of nerve growth factor (NGF). Addition of colchicine and exposure to different explanted peripheral tissues were also tried. Ganglia from the younger embryos (8-12 days) cultured for 24 h with added NGF showed a weak SP-like immunoreactivity (SPLI) in some cell bodies and strong specific immunofluorescence in nerve fibres growing out from the ganglia. In spinal ganglia of the older embryos (14 and 16 days) and newly hatched chickens cultured with and without NGF the concentration of SPLI in the cell bodies was considerably higher. Addition of colchicine to spinal ganglia cultured 12 h in NGF-medium, resulted in retraction of nerve fibres and strongly fluorescent, expanded nerve fibres were observed in peripheral parts of the ganglia. Explants of skin placed near the spinal ganglia stimulated the outgrowth of fibres, some of them containing SPLI. A few fluorescent fibres were also seen within the skin explants. Also heart tissue explants stimulated outgrowth of nerve fibres, but innervation of these explants with SPLI-containing nerves could not be observed. Nerve fibre-extension from the spinal ganglia was not stimulated by spinal cord explants. The present results support the existence of SP-containing primary sensory neurons in chickens.


Biochemical studies in a patient with a Tangier syndrome. The chemical composition of the major classes of lipids were evaluated in the plasma and in various other tissues of a 68-year-old woman with a syringomyelia-like syndrome affecting cranial, cervical and brachial regions. No tonsillar abnormalities were apparent on visual examination of the oropharynx but the absence of alpha-lipoproteins on serum lipoprotein electrophoresis prompted the tentative diagnosis of Tangier disease. The diagnosis was confirmed by lipid, lipoprotein and apolipoprotein analyses of the plasma. The plasma cholesterol was low (93-113 mg/dl) and the triglyceride concentration normal (133-160 mg/dl). The very low density lipoproteins had normal chemical composition and morphology, but migrated with beta rather than pre-beta mobility on paper electrophoresis. Low density lipoproteins were deficient in cholesteryl esters and enriched in triglycerides; their electrophoretic mobility and morphology were normal. A small amount of high density lipoprotein (approximately 1.4 mg/dl) was recovered from the plasma. This contained few particles of the size of normal high density lipoprotein and polyacrylamide gel electrophoresis of the lipid-free protein demonstrated a disproportionate increase in the A-II apolipoprotein. All of these abnormalities are consistent with Tangier disease. The serum concentration of glycosphingolipids was approximately 40% lower than normal, with the most marked reductions in the glucosylceramide (GL-1a) and trihexosylceramide (GL-3a) fractions. The relative quantity of long chain fatty acids (23 or more carbons) in serum sphingomyelin was reduced about 38% of that in control sera. Serum lecithin:cholesterol acyltransferase (EC 2.3.1.43; LCAT) activity was 25% of normal and the reduced activity was shown not to be related to a change of enzyme specificity or to a lack of appropriate substrate. These findings are likely related to the HDL deficiency which characterizes Tangier disease. A biopsy sample of apparently normal tonsil contained three to four times the normal amount of cholesterol, and the increase was due entirely to abnormal quantities of cholesteryl esters. Of great interest was the chemical documentation of increased cholesteryl esters in a nerve biopsy specimen. These findings indicate that the neurologic as well as the reticuloendothelial manifestations of Tangier disease may be related to cholesteryl ester accumulation. Lipoprotein profiles, their triglyceride and cholesterol concentration, and LCAT activity were obtained on the plasma of 7 closely related members of the kinship. None of these relatives were found to have the biochemical derangement of Tangier disease.


Effects of ageing on the histochemically demonstrable catecholamines and acetylcholinesterase of human sympathetic ganglia. The sympathetic ganglia of adult and aged humans were obtained during vascular, gynaecological and urological surgery, and studied using the formaldehyde-induced fluorescence (FIF) method for histochemical demonstration of catecholamines. Microspectrofluorimetry was applied to characterize the emission spectra of the flurophores. The sympathetic ganglia contained two types of cells exhibiting FIF: the adrenergic neurons and the small, intensely fluorescent (SIF) cells. The adrenergic neurons contained pigment granules exhibiting autofluorescence with emission maximum at 530---540 nm. The number of these granules increased with age while the FIF of the neurons decreased. In the oldest patients, most of the neurons in the sympathetic ganglia showed only pigment fluorescence but not FIF. The decrease of the perikaryonal catecholamine stores is interpreted as a degenerative change leading to impaired function of the neurons. The patterns of AChE did not change with age. The SIF cells were sparse and were mostly observed near the ganglia, forming paraganglia of varying size. Because of the rarity of the SIF cells, the effect of ageing could not be judged reliably.


The effect of levamisole on the canine central nervous system. Levamisole was given orally to 3 groups of dogs, totaling 56 animals. Drug administration period varied from 1 to 120 days. All animals were killed and the central nervous system was examined histologically. Lesions were found in 44 of 56 dogs. These consisted of disseminated perivascular cuffing with mononuclear cells throughout the brain and meninges. The severity of the perivascular cuffing varied considerably and could not be correlated to the length of the drug administration period nor to any other variables. There was no damage to the neural tissues associated with the perivascular cuffing. There was evidence of regression of the lesions whether levamisole treatment was continued or not. The changes observed in this study were considered to be related to the known immunomodulating properties of levamisole. The pathogenesis of this change in uncertain.


Postsynaptic specializations at excitatory and inhibitory cholinergic synapses. In serial sections of neurons in the paravertebral ganglia of the frog (Limmodynastes dumerili), the postsynaptic structures termed 'postsynaptic bar' (PSB) and 'junctional subsurface organ' (JSO) were never observed in the same ganglion cell. Further, PSBs were found mostly in small ganglion cells (less than 22 micrometer), while JSOs were found mostly in large ganglion cells (up to 45 micrometer). Between 10 and 22 PSBs were located at both 'spine' and 'non-spinous' somatic synapses of the smaller ganglion cells; while 8 to 16 JSOs were located largely in the axon hillock region of the larger ganglion cells. Based on these observations, it is suggested that the two ganglion cell populations represent the B and C cell types defined according to electrophysiological data. Further, since the nerve terminals adjacent to both these postsynaptic structures appear to be cholinergic according to their vesicular content, this provides some basis for suggesting that JSOs are associated with slow excitatory synapses, while PSBs are present at slow inhibitory synapses.