Attachment role of gonococcal pili. Optimum conditions and quantitation of adherence of isolated pili to human cells in vitro.

Gonoccocal pili facilitate attachment of virulent Neisseria gonorrhoeae to human cells. To characterize this attachment function, purified gonococcal pili isolated from four strains possessing antigenically distinct pili were radiolabeled with 125I and used to measure the attachment of pili to various human cells in vitro. Human buccal and cervical-vaginal mucosal epithealial cells, fallopian tube mucosa, and sperm bound pili in greater numbers per micrometer2 of surface area (1--10) than fetal tonsil fibroblasts, HeLa M cells, erythrocytes, or polymorphonuclear leukocytes. This cell specificity of attachment suggests a greater density of membrane pili binding sites on cells similar or identical to cells from natural sites of infection. The pili binding sites were quantitated as 1 X 10(4) per cervical-vaginal squamous cell. Pili of all antigenic types attached equally to a given cell type, implying that the attachment moiety of each pilus was similar. Attachement of gonoccocal pili to human cells occurred quickly with saturation of presumed receptor sites within 20--60 min. Attachment was temperature dependent (37 degrees greater than 20 degrees greater than 4 degrees C), and pH dependent (3.5 less than 4.5 less than 5.5 less than 7.5). Attachment was inhibited by antibody to pili (homologous pili Ab greater than heterologous Ab). The extent of possible protection against gonococcal infection due to inhibition of pili-mediated attachment might prove limited as a result of the considerable antigenic heterogeneity among pili and the observation that blockage of pili attachment is maximal only with antibody to pili of the infecting strain.


Parathyroid hormone responses to catecholamines and to changes of extracellular calcium in cows.

Modifications of the plasma level of immunoreactive parathyroid hormone (PTH) in cattle were induced by changes of the plasma concentrations of epinephrine, isoproterenol, or calcium. During abrupt hypocalcemia, PTH, obtained by infusions with ethylene glycol-bis (beta-aminoethylether) N, N'-tetraacetate (EGTA), increased during the first 4-8 min. After a transient decline, the hormone levels rose again and remained elevated. Infusions of calcium suppressed the hypocalcemia-induced augmentation of PTH levels within a few minutes. Prolonged epinephrine (and isoproterenol) infusions also rapidly increased PTH levels, however, in this case, they returned to basal concentrations after 50-60 min. Additional epinephrine infusions could not further raise PTH values. Moreover, three short-lasting infusions of epinephrine (7 min each), given at 30-min intervals, increased PTH levels to the same extent, whereas additional infusions were much less effective. The PTH response to epinephrine was completely restored, when the interval after a prolonged epinephrine infusion had been prolonged to > 100 min. During moderate hypocalcemia, occurring at the end of EGTA infusions and lasting for 90 min, the PTH response to a short-lasting epinephrine infusion (7 min) was more pronounced than in normocalcemic animals. During severe hypocalcemia, in which superimposed short-lasting infusions of EGTA (7 min) led to an additional abrupt fall of plasma calcium concentrations but not to a corresponding additional rise of the PTH levels, epinephrine rapidly and further increased PTH concentrations. On the other hand, at the end of prolonged infusions of epinephrine, when additional infusions of epinephrine were ineffective in raising PTH levels, EGTA-induced hypocalcemia consistently increased PTH concentrations. The EGTA-induced augmentation of PTH levels was enhanced by epinephrine and isoproterenol but not by propranolol. The present findings indicate, that variations of the extracellular calcium concentrations and beta-adrenergic agonists modify PTH levels by two different and independent mechanisms. On the other hand, it appears that the magnitude of change of the PTH levels to either stimulus is partially modulated by exposure to the other.


Difference between type I autoimmune inhibitors of fibrin stabilization in two patients with severe hemorrhagic disorder.

Inhibitors of fibrin stabilization of apparently autoimmune origin, found in two severely bleeding unrelated patients (W. G. and G. A.), were compared with regard to their biological target specificities, potencies and immunological characteristics. Both interfered only with the activation of fibrin stabilizing factor (coagulation Factor XIII) and, while totally preventing the conversion of this zymogen to the functional transamidating enzyme, fibrinoligase (Factor XIII(a)), they showed very little inhibition toward the enzyme itself. Thus, according to the classification of Lorand concerning biological specificities, both can be characterized as Type I inhibitors of fibrin stabilization. Potencies of the two inhibitors were quite similar when measured in conjunction with the plasma zymogen, but they differed remarkably in tests with platelet Factor 13. The inhibitor of patient W. G. prevented the activation of the zymogen from platelets, but that of G. A. had no effect on the platelet factor. It may therefore be concluded that the inhibitor of W. G. is directed exclusively against the a subunit which is a common constituent of plasma as well as platelet factors. The inhibitor of G. A., however, must be targeted against determinants uniquely characteristic for the ab ensemble of the plasma zymogen including the b subunit. On the basis of this difference in target specificity, the inhibitor of W. G. is designated as Type I-1 and that of G. A. as Type I-2. The inhibitors of both patients were isolated as immunoglobulins, and neutralization tests revealed that the antibody of W. G. comprised mainly heavy chains of the IgG1 and light chains of the kappa class. The antibody of G. A. proved to be considerably more heterogeneous and contained IgG1 and IgG3 heavy chains as well as kappa- and lambda-light chains. The finding that the antibody of W. G. inhibited conversion of platelet Factor 13 and also its thrombinmodified form, but had no effect on the thrombin and Ca(2+)-activated factor, is an indication that antigenic determinants existing both on the native zymogen and on its hydrolytically modified form become buried in the Ca(2+)-dependent step of activation. This is clear evidence for the occurrence of a significant conformational change in the protein structure attendant to the process of unmasking of its enzymic activity.


Quantitative influence of antibody and complement coating of red cells on monocyte-mediated cell lysis.

Monocyte-mediated lysis in vitro of human red cells coated with measured amounts of immunoglobulin G (IgG) or complement were studied. 1,000-1,500 molecules of IgG anti-D are necessary to effect measurable lysis, and lysis increases linearly with increasing levels of antibody sensitization. 100 microgram/ml of IgG1 abolished lysis even at maximal levels of anti-D sensitization (15,000 molecules/cell). Two isoimmune IgG anti-A or anti-B antisera were 5 to 10-fold less efficient in promoting phagocytosis or lysis per molecule of IgG bound; however, because of the greater antigen density of A or B, more than 100,000 molecules IgG/cell could be bound, producing equivalent lysis to anti-D-coated cells. Although inhibition by IgG1 was similar at equivalent levels of sensitization with anti-A, anti-B, or anti-D at high levels of coating with anti-A or anti-B (not attainable with anti-D), lysis was not inhibited by IgG1. Cells coated with human complement components alone were not lysed by monocytes; however, complement coating augmented IgG-mediated lysis and reduced the quantity of anti-D necessary to produce lysis to less than 1,000 molecules/cell. After thorough degradation of C3b by serum to C3d, complement augmentation persisted.


Deoxyguanosine triphosphate as a possible toxic metabolite in the immunodeficiency associated with purine nucleoside phosphorylase deficiency.

Purine nucleoside phosphorylase (PNP) deficiency is associated with a severe defect in thymus-derived (T)-lymphocyte function combined with normal bone marrow-derived (B)-lymphocyte function. To investigate the role of this enzyme deficiency in the resulting immune dysfunction, we measured the levels of ribonucleoside and deoxyribonucleoside triphosphates in erythrocytes from two unrelated PNP-deficient, T-lymphocyte-deficient patients. Both PNP-deficient patients have abnormally high levels of deoxyguanosine triphosphate (deoxy-GTP) in their erythrocytes (5 and 8 nmol/ml packed erythrocytes). In contrast, normal controls and adenosine deaminase-deficient, immunodeficient patients do not have detectable amounts of deoxyGTP (<0.5 nmol/ml packed erythrocytes). We propose that deoxyguanosine, a substrate of PNP, is the potentially lymphotoxic metabolite in PNP deficiency. The mechanism of toxicity involves phosphorylation of deoxyguanosine to deoxyGTP, which acts as a potent inhibitor of mammalian ribonucleotide reductase.


The kallikrein-kinin system in Bartter's syndrome and its response to prostaglandin synthetase inhibition.

The kallikrein-kinin system was characterized in seven patients with Bartter's syndrome on constant metabolic regimens before, during, and after treatment with prostaglandin synthetase inhibitors. Patients with Bartter's syndrome had high values for plasma bradykinin, plasma renin activity (PRA), urinary kallikrein, urinary immunoreactive prostaglandin E excretion, and urinary aldosterone; urinary kinins were subnormal and plasma prekallikrein was normal. Treatment with indomethacin or ibuprofen which decreased urinary immunoreactive prostaglandin E excretion by 67%, decreased mean PRA (patients recumbent) from 17.3+/-5.3 (S.E.M.) ng/ml per h to 3.3+/-1.1 ng/ml per h, mean plasma bradykinin (patients recumbent) from 15.4+/-4.4 ng/ml to 3.9+/-0.9 ng/ml, mean urinary kallikrein excretion from 24.8+/-3.2 tosyl-arginine-methyl ester units (TU)/day to 12.4+/-2.0 TU/day, but increased mean urinary kinin excretion from 3.8+/-1.3 mug/day to 8.5+/-2.5 mug/day. Plasma prekallikrein remained unchanged at 1.4 TU/ml. Thus, with prostaglandin synthetase inhibition, values for urinary kallikrein and kinin and plasma bradykinin returned to normal pari passu with changes in PRA, in aldosterone, and in prostaglandin E. The results suggest that, in Bartter's syndrome, prostaglandins mediate the low urinary kinins and the high plasma bradykinin, and that urinary kallikrein, which is aldosterone dependent, does not control kinin excretion. The high plasma bradykinin may be a cause of the pressor hyporesponsiveness to angiotensin II which characterizes the syndrome.


Lower levels of thyrotropin-releasing hormone-degrading activity in human cord and in maternal sera than in the serum of euthyroid, nonpregnant adults.

Thyrotropin-releasing hormone (TRH)-degrading activity was investigated in human cord, maternal, and euthyroid adult sera by measuring (a) the rate of disappearance of TRH and (b) the rate of formation of degradation products. The rate of TRH degradation in cord and maternal sera was 25-33% of that in euthyroid adult serum. Concomitantly, in cord and maternal sera, the rate of formation of proline, a major TRH degradation product in serum, was one-quarter to one-third that in euthyroid adult sera. The differences were highly significant (P less than 0.001). The decreased levels of TRH-degrading activity in cord and maternal sera cannot be explained by (a) the presence of a dialyzable inhibitor, (b) the absence of an activator of TRH degradation, or (c) a reversal of the degradation process. There was no difference in the types of radioactive degradation products formed by cord, maternal, and euthyroid adult sera. The low level of TRH-degrading activity and its possible relationship to high thyrotropin-stimulating hormone levels in cord serum suggest that TRH-degrading activity may be a factor to consider in investigations of the perinatal pituitary-thyroid axis, but further studies are needed to determine the role of serum degradation of TRH in regulating physiological levels of TRH.


Increased glycosphingolipid excretion associated with proteinuria.

The urine of patients with proteinuria of various etiologies was examined to determine if proteinuria alone was associated with significant glycosphingolipiduria. In all cases of proteinuria examined, the level of glycosphingolipids in the urine was found to be markedly elevated. There was no evidence of a glycosphingolipid storage disorder in any case. It was concluded that significant glycosphingolipiduria may occur in proteinuria as well as in the glycosphingolipid storage disorders.


Hepatic conversion of bilirubin monoglucuronide to diglucuronide in uridine diphosphate-glucuronyl transferase-deficient man and rat by bilirubin glucuronoside glucuronosyltransferase.

The microsomal enzyme uridine diphosphate (UDP) glucuronate glucuronyltransferase (E.C. 2.4.1.17) catalyzes formation of bilirubin mono-glucuronide from bilirubin and UDPglucuronic acid. Bilirubin glucuronoside glucuronosyltransferase (E.C. 2.4.1.95), an enzyme concentrated in plasma membrane-enriched fractions of rat liver, converts bilirubin monoglucuronide to bilirubin diglucuronide. Bilirubin glucuronoside glucuronosyltransferase activity was studied in homogenates of liver biopsy specimens obtained from patients with the Crigler-Najjar syndrome (Type I) and in subcellular liver fractions of rats homozygous for UDP glucuronate glucuronyltransferase deficiency (Gunn strain). In patients with the Crigler-Najjar syndrome (Type I) and in Gunn rats, hepatic UDPglucuronate glucuronyltransferase activity was not measurable; however, bilirubin glucuronoside glucuronosyltransferase activity was similar to that in normal controls. The subcellular distribution of bilirubin glucuronoside glucuronosyltransferase activity in Gunn rat liver was similar to the distribution observed in normal Wistar rat liver.When bilirubin monoglucuronide was infused intravenously into Gunn rats, 29+/-5% of the conjugated bilirubin excreted in bile was bilirubin diglucuronide. After transplantation of normal Wistar rat kidney, which contained UDPglucuronate glucuronyltransferase activity, in Gunn rats, the serum bilirubin concentration decreased by 80% in 4 days. The major route of bilirubin removal was biliary excretion of conjugated bilirubin, approximately 70% of which was bilirubin diglucuronide. Although patients with the Crigler-Najjar syndrome (Type I) and Gunn rats lack UDP glucuronate glucuronyltransferase, their livers enzymatically convert bilirubin monoglucuronide to diglucuronide in vitro. Conversion in bilirubin monoglucuronide to diglucuronide was demonstrated in Gunn rats in vivo.


Cell-mediated immunity to Pityrosporum orbiculare in tinea versicolor.

Pityrosporum orbiculare, the presumed etiologic agent of tinea versicolor, was cultured in vitro and antigenic extracts prepared from the cultured organisms. Studies with lymphocytes from human cord blood and peripheral blood of guinea pigs demonstrated that such extracts were not mitogenic. Further studies in guinea pigs indicated that the animals could be sensitized by the injection of P. orbiculare extract in Freund's complete adjuvant and that this extract could elicit lymphocyte transformation and delayed skin test responses in sensitized animals. A group of 12 tinea versicolor patients and 15 normal subjects were studied in vitro for cell-mediated immunity to P. orbiculare extract. The majority of the subjects tested in both groups demonstrated positive lymphocyte transformation responses to this extract, as well as to standard mitogens and common microbial antigens. However, lymphocytes from tinea versicolor patients produced significantly less leukocyte migration inhibitory factor activity when stimulated by Candida albicans and P. orbiculare extracts than did lymphocytes from normal subjects. This was also true if only subjects with positive lymphocyte transformation responses to these antigens were considered. Leukocyte migration inhibitory factor responses to streptokinase/streptodornase were not significantly different between the two groups. Therefore, it appears that although both normal subjects and tinea versicolor patients demonstrate prior sensitization to antigens of P. orbiculare, the effector function of lymphocytes from most tinea versicolor patients appears to be impaired in that they produce subnormal amounts of the mediator leukocyte migration inhibitory factor when stimulated with antigenic extracts of this organism.


Verification of human fetal breathing with phased array ultrasound imaging.

Continuous observation of fetal movement patterns is a novel and useful capability of new high-speed ultrasound imaging systems. Confirmatory documentation of human fetal breathing as a component of these movement patterns has been achieved using a phased-array real time ultrasound sector scanning system. This system permits direct visualization of fetal breathing movements. Permanent recordings can be made on videotape. Recordings can also be made as a time-motion echocardiograms during continuous observation of the full sector. Fetal breathing movements were seen in five patients. The earliest period of gestation at which fetal breathing was seen was 20 weeks.


B scan detection of pelvic masses: accuracy compared to the barium enema, intravenous pyelogram.

One hundred fifty nine pelvic ultrasonic examinations were performed; 54 were verified. The relative diagnostic accuracy of ultrasound, intravenous pyelograms, and barium enemas in detecting pelvic masses is discussed. Ultrasound is highly accurate except in ascites. While barium enema and intravenous pyelogram are both inaccurate. Ultrasound should be the initial examination for the evaluation of patients with a possible pelvic mass.


The use of ultrasound to diagnose a pseudomass effect secondary to abdominal ascites.

Two cases of abdominal ascites in which a mass lesion was simulated on the roentgenogram are reported. Sonography permits ready differentiation of an encapsulated from a nonencapsulated fluid collection.


Echocardiographic features in a case of intrapericardial teratoma.

An infant presented with symptoms of congestive heart failure. Ultrasound examination revealed a dense layer of echoes at the root of the aorta, a large anterior pericardial effusion, and coarse fluttering of the right ventricular wall. The clinical diagnosis of intrapericardial teratoma was confirmed by cineangiography and surgical resection. The pathological examination was consistent with benign teratoma. A postoperative ultrasound examination revealed absence of pericardial effusion and tumor echoes. This appears to be the first echocardiographic report of a pericardial tumor in an infant.


Echography of splenic infarct in a case of systemic lupus erythematosus.

A 29 year old female with systemic lupus erythematosus had a splenic infarct. The echogram showed a 4 x 4 x 5 cm cluster of echoes. After splenectomy the preoperative echograms were matched to the gross pathological findings and a post mortem water bath scan. In this single patient, the echosplenograms were of considerable aid in confirming the accuracy of the diagnosis of splenic infarct.


Case report: benign liver tumor with central necrosis.

A 38 year old previously well woman had sudden onset of upper abdominal pain and fever. Ultrasound examination revealed a necrotizing lesion in the liver. Arteriography revealed findings consistent with an adenoma or focal nodular hyperplasia. A right lobectomy and wedge resection of a similar lesion in the left lobe were done. Microscopy of both lesions indicated focal nodular hyperplasia. Adenoma is said to be related to the contraceptive oral hormone; focal nodular hyperplasia not. But it is possible that both may have an increased incidence of bleeding in the users of the oral contraceptive hormones.


Anatomic variation of portal venous anatomy in the porta hepatis: ultrasonographic evaluation.

The appearance of the portal vein as it crosses anterior to the inferior vena cava and enters the liver at the porta hepatis was evaluated on 100 longitudinal and 100 transverse ultrasonograms. Three major variations were noted on the parasagittal scans, while four major variations were evident on the transverse images. These variations were primarily related to the size of the left portal vein and the angle at which the left portal vein coursed away from the main portal vein. The appearance and course of the proximal right portal vein was extremely constant and may therefore be used as a landmark to detect pathologic processes in the porta hepatis. Detection of altered anatomy in this region may be especially helpful in correctly differentiating dilated intrahepatic bile ducts from normal portal veins.


Ultrasonographic identification of dilated intrahepatic bile ducts and their differentiation from portal venous structures.

The appearance of dilated intrahepatic bile ducts was evaluated on ultrasonograms of 50 patients with proven extrahepatic biliary obstruction. Five characteristic changes allowed differentiation between biliary and portal venous systems. These changes included: 1) alteration in the anatomic pattern adjacent to the main right portal venous segment and the main portal vein bifurcation. 2) Irregular walls of dilated bile ducts. 3) Stellate confluence of dilated bile ducts. 4) Acoustic enhancement by dilated bile ducts. 5) Peripheral location of dilated bile ducts. Many patients exhibited more than one of these findings. Parasagittal scans of the main right portal vein were the most sensitive for detection of intrahepatic ductal dilatation. Recognition of the characteristic changes and knowledge of the portal venous anatomy makes it possible to diagnose extrahepatic biliary obstruction with a high degree of confidence.


Effects of activated carbon, phenobarbital, and vitamins A, D, and E on polybrominated biphenyl excretion in cows.

Twelve cows environmentally contaminated with polybrominated biphenyl residues were in a balanced two-period changeover experiment. The treatments were activated carbon and sodium phenobarbital; sodium phenobarbital and injections of vitamins A, D, and E; activated carbon, phenobarbital, and vitamins A, D, and E; and control. A standard roughage and concentrate diet was fed. Average initial concentrations of polybrominated biphenyls in the milk fat ranged from 92 to 236 ppm. The experimental treatments did not affect significantly excretion of polybrominated biphenyls in milk and feces or the apparent half-life of residues in milk fat averaged 60 days but ranged from 36 to 301 days. The longer half-life in early lactation than in later lactation indicated an effect of change of body weight on half-life. Milk was the major route of excretion, averaging 6.5 times that of fecal excretion. Polybrominated biphenyl in milk fat, body fat, blood, and feces followed parallel concentrations troughout the study.


Cell binding and growth inhibition by hexachlorophene of decanoate and their reversibility.

More than 80% of the hexachlorophene added to a Bacillus subtilis culture binds to the cells. Complete growth inhibition requires 6 x 10(5) molecules bound per cell. In contrast, more than 99% decanoate remains in solution and 3.8 x 10(7) molecules bound per cell are needed to inhibit growth. Centrifugation and resuspension of cells in growth medium removes only decanoate, whereas the addition of 1% bovine serum albumin to the growth medium removes both inhibitors from their binding sites on the cells. The addition of untreated cells to a hexachlorophene-treated culture enables the hexachlorophene molecules to redistribute among all the cells with the result that the inhibited cells can resume growth.


Use of immunocytochemical techniques for the localization of human placental lactogen.

The recent claim by Gau and Chard (Br J Obstet Gynaecol 83:876, 1976) that, on theoretical grounds, it may be impossible to demonstrate the presence of human placental lactogen in placental tissue using the immunoperoxidase technique, has been reinvestigated. Placental tissue fragments fixed in Carnoy's fluid retained their morphologic identity compared with tissue fixed in formalin. Using these nonformalin fixed tissues, human placental lactogen was successfully localized within the cytoplasm of the syncytial layer of the placental villus. It is concluded that placental villi at term do in fact contain sufficient human placental lactogen to be demonstrated using the immunoperoxidase technique in contrast to the observation of Gau and Chard.


A new method for the study of glutaraldehyde-induced crosslinking properties in proteins with special reference to the reaction with amino groups.

A new method for the study of glutaraldehyde reactions with proteins is presented. Glutaraldehyde-reacted protein is in a first step isolated and then in a second step reacted with aminohexyl groups bound to Sepharose particles. This reaction is linear at low protein concentrations and proceeds rapidly when proteins are reacted with 100-fold and 1000-fold molar excess of glutaraldehyde. This method enables the study of glutaraldehyde-induced crosslinking properties of the modified proteins as an isolated property with high reliability.


Genetic control of immunologic unresponsiveness to adjuvant-free solutions of beta-D-galactosidase. I. Inheritance of the Ir-Z1 and ir-Z2 loci in mice.

Two genetic loci, Ir-Z1 and ir-Z2, controlling the immune response to adjuvant-free bacterial beta-D-galactosidase (Z) are present in inbred mouse strains SJL/J and CE/J, respectively. Each locus segregates as a single, autosomal gene: Ir-Z1 as dominant and ir-Z2 as recessive. The response is characterized by production of activating and precipitating IgG. Maximal levels of circulating IgG occur between 16 and 20 days after immunization with a single, 50-microgram dose of enzyme. Failure of proteins other than Z to elicit an immune response indicates that the Ir-Z control is specific for determinant(s) of this enzyme. The immunogenicity of beta-D-galactosidase preparations cannot be attributed to either the catalytic activity of the enzyme or adjuvant contamination. Non-responder mice acquire immunologic memory without detectable increase in circulating specific IgG under the same conditions that elicit antibody production in responder strains.


Immunoglobulin secretion by human splenic lymphocytes in vitro: the effects of antibodies to IgM and IgD.

The effects of F(ab')2 fragments of affinity-purified rabbit anti-human mu chain antibody (RaHmu) and rabbit anti-human delta chain antibody (RaHdelta) on spontaneous and mitogen-stimulated immunoglobulin (Ig) secretion by normal human spleen cells were studied. IgM and IgG secretion by human spleen cells cultured in vitro was measured by incubating the cells with 3H-amino acids precipitating the secreted labeled Ig with anti-Ig, and analyzing the precipitates by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Both RaHmu and RaHdelta suppressed spontaneous and LPS-induced IgM and IgG secretion as well as PWM-stimulated IgG secretion. In different experiments, RaHmu and RaHdelta either suppressed or augmented PWM-induced IgM secretion. The anti-Ig induced augmentation of PWM-triggered IgM secretion was most apparent when spleen cells were cultured at lower cell densities or when lower concentrations of anti-Ig were employed. These date indicate that perturbation of B cell surface immunoglobulin receptors with specific anti-Ig antibody can alter markedly the ability of these cells to differentiate into antibody-secreting cells.


Pre-B cells: bone marrow persistence in anti-mu-suppressed mice, conversion to B lymphocytes, and recovery after destruction by cyclophosphamide.

Chronic treatment of mice from birth with anti-mu antibodies aborts development of B lymphocytes and plasma cells. In these studies we show that bone marrow from anti-mu-treated mice contains a population of cells with cytoplasmic IgM, but which lack detectable cell-surface IgM. These cells are analogous to pre-B cells, defined in ontogenetic studies as the immediate precursors of B lymphocytes. Pre-B cells from bone marrow of anti-mu treated mice retain their functional integrity, as evidenced by their ability to give rise to sIgM+, LPS-responsive lymphocytes in culture. We also show that cyclophosphamide treatment destroys pre-B cells and that recovery of pre-B cells in bone marrow precedes the regeneration of sIgM+ B lymphocytes. Generation of B lymphocytes in adult mice apparently occurs exclusively in the bone marrow because induction of extramedullary hemopoiesis in spleen was not accompanied by the appearance of pre-B cells in that organ.


Linkage between a gene for a serum protein and the gene for the Ig kappa light chain in rabbits.

A rabbit serum protein (Prt) that migrates ahead of transferrin in polyacrylamide gel electrophoresis is inherited in a simple Mendelian fashion. The gene for this protein is linked to the gene for the Ig kappa light chain and the degree of linkage is calculated as 23.5 +/- 4.7 centimorgans.


Alloantigen-induced T helper activity. I. Minimal genetic differences necessary to induce a positive allogeneic effect.

Addition of histoincompatible lymphocytes can influence the course of ongoing immune responses. Such allogeneic effects may either augment or diminish immune responses. We describe here the minimal genetic differences necessary to generate positive allogeneic effects (allohelp) in a humoral immune response. The antibody response to sheep erythrocytes of T cell-depleted mouse spleen cells was reconstituted by addition of syngeneic or allogeneic nylon wool column-passaged spleen T cells. T cells were pretreated with mitomycin C before culture to prevent development of allo-suppression and cytotoxic lymphocytes. Positive allogeneic effects were operationally defined as superior helper effects (to generate greater antibody forming cell responses) with T cells allogeneic rather than syngeneic to the responding B cells. Thus, addition of allogeneic T cells resulted in many more antibody forming cells than did equal numbers of syngeneic T cells, and fewer allogeneic than syngeneic T cells were necessary to generate comparable responses. With congenic, recombinant, and mutant mouse lines, genetic differences in the H-2 complex and those associated with Mls were each sufficient to provide positive allogeneic effects. With intra-H-2 recombinants, differences at either I or D were sufficient. A disparity at H-2K alone, as provided by the H-2 mutant B6.C-H-2ba against the parental line C57BL/6By, also induced helper effects. The significance of these results is discussed.


Magnetically responsive polyacrylamide agarose beads for the preparation of immunoabsorbents.

Glutaraldehyde-activated magnetically responsive polyacrylamide agarose beads have been employed to bind bovine serum albumin and human, sheep and rabbit IgG. These were tested for their effectiveness as immunoabsorbents and were found to allow isolation of pure antibodies in high yields. The use of magnetically responsive beads as the solid support in immunoabsorption procedures renders isolation of antibodies easy and rapid.


[3H]serotonin release: an improved method to measure mast cell degranulation.

A method based on the release of tritium-labelled serotonin by activated mast cells in rodents is described. Mast cells incorporate labelled serotonin selectively and release the label after activation by non-specific stimulators (compound 48/80, polymyxin B sulphate, ATP, bovine chymotrypsin and L-alpha-lysophosphatidylcholine) or anaphylactic antibody and the corresponding antigen. These two types of activation were investigated in comparison with the toluidine blue microscopic rat mast cell degranulation test, and a methodological study of the release of [3H]serotonin is described. The measurement of labelled serotonin release provides a simple and quick assay of mast cell degranulation compared to the time required for the classical rat mast cell degranulation technique and achieves a greater sensitivity.


Identifying immunoglobulin isotypes, allotypes and idiotypes by a hemolytic assay in gel.

We developed a hemolytic radial immunodiffusion assay for identifying immunoglobulin (Ig) isotypes, allotypes and idiotypes by using gels containing erythrocytes coated with anti-Ig antibody or erythrocytes coated with Staphylococcal protein A. These indicator cells lysed specifically when treated sequentially with Ig antigen, the appropriate anti-Ig antiserum (developer) and complement. To identify these Ig subpopulations, we used monospecific indicator cells, e.g. erythrocytes coated with antibody specific for an Ig isotype, and developers with broader specificities ('multispecific'), e.g. antiserum to Fab. Alternatively, we used 'multispecific' indicator cells, e.g. erythrocytes coated with antibody to Fab and monospecific developers, e.g. antiserum to Ig idiotype. To identify Ig subpopulations specifically, either the indicator cells or the developer need to be monospecific. When both the indicator cells and the developer were monospecific, e.g. to allotype and to isotype, the specificity was determined by both reagents and ultimately restricted by the reagent with the narrower specificity, that is, reacting with the smallest Ig subpopulation. This sensitive hemolytic assay may be used to quantitate subpopulations of Ig molecules and may be modified into a reverse plaque forming cell assay to count lymphocytes secreting a given Ig class, type, allotype and idiotype.


Pathogenesis of Pseudomonas aeruginosa pneumonia during immunosuppression.

A guinea pig model of immunosuppression was utilized to study the effects of immunosuppressive chemotherapy on lung response to challenge with Pseudomonas aeruginosa. Study groups included normal guinea pigs, as well as guinea pigs that received a one-week course of cortisone acetate (CA, 100 mg/kg per day) plus 15 mg of cyclophosphamide (CTX)/kg per day (CA + LoCTX group) or 30 mg of cyclophosphamide/kg per day (CA + HiCTX group). Separate groups received CA or HiCTX alone. Intratracheal instillation of P. aeruginosa resulted in bilateral hemorrhagic pneumonia in both normal and immunosuppressed animals. Survival was 100% for normal animals and for those given CA alone, 67% in the CA + LoCTX and the HiCTX groups, and 0 in the CA + HiCTX group. Increased mortality correlated with a diminished polymorphonuclear leukocyte inflammatory response in infected lung tissues and also with the addition of CA to CTX. Clearance of viable P. aeruginosa from lung tissue was significantly reduced in animals receiving the combination CA + HiCTX. Thus, decreased lung inflammation and the addition of CA appeared to be important determinants for fatal pseudomonas pneumonia.


Amino terminal sequence of amyloid P-component isolated from serum.

Amyloid AP (protein SAP) has been isolated from human serum by affinity chromatography using specific antiserum and shown to have the same immunologic and ultrastructural characteristics as the pentagonal protein isolated from amyloid tissue (AP). Polyacrylamide gel electrophoresis in SDS reveals a single subunit of 25,000 daltons for both SAP and AP preparations. N-terminal amino acid sequence of this alpha globulin to 13 residues reveals complete homology with the tissue-extracted protein, suggesting that AP is incorporated into, or adsorbed onto, amyloid fibrils without biochemical alteration.


The picomole determination of free and total cholesterol in cells in culture.

An enzymatic, fluorometric method for the determination of free and total cholesterol in cells in culture is presented. The method is simple, requiring one reagent that includes all of the enzymes and a second reagent that increases the pH, which enhances the fluorescence of the product. The method is based on the enzymatic hydrolysis of cholesteryl esters to free cholesterol, the oxidation of cholesterol with the liberation of hydrogen peroxide, and the reaction of this peroxide with a fluorogen to form a fluoresencet product in the presence of a peroxidase. It is rapid, in that free cholesterol can be read in 5 minutes and total cholesterol after 20 minutes. The precision of the method is greater than that obtained from gas-liquid chromatography.


Isolated T wave alternans elicited by hypocalcemia in dogs.

Isolated T wave alternans (TWA) could be consistently induced in 13 dogs by infusion of an acid dextrose solution (ACD) and in nine with a 2% EDTA disodium solution. To study the factors concerned in evoking TWA, serial determinations of total and ionized serum calcium (ICa), Mg, K, pH, pCO2 and pO2 were performed. Arterial or LV pressures and LV dp/dt as well as a standard electrocardiographic lead were monitored. TWA appeared after the QT interval was significantly prolonged and was associated with a fall in LV pressure and with mechanical alternans. QT alternans could also be detected in 50% of the cases. ICa levels were significantly reduced at the moment of appearance of the TWA. Data obtained support the conclusion that TWA was the result of a reduction in the level of the ICa, probably interfering with the calcium transport mechanisms of the myocardial cell, although the possibility that the alternans may be due to other effects of the two agents employed unrelated to calcium lowering cannot be excluded.


Sulphation factor (somatomedin activity) in experimental protein malnutrition in the rat.

In a rat model of protein malnutrition in which the failure of growth is a major feature, a low level of bioassayable sulphation factor activity was present in the serum, associated with normal levels of growth hormone and low insulin in the plasma. The administration of pharmacological doses of human or bovine growth hormone did not increase the amount of sulphation factor activity in the serum or the width of the tibial epiphyses in the protein-malnourished animals. The basal and serum-stimulated incorporation of 35SO2-4 into the costal cartilages of malnourished animals did not differ from that of controls, which suggests that the responsiveness of the end-organs was normal.


Pyroglutamyl-N3im-methyl-histidyl-prolineamide (methyl-thyrotrophin releasing hormone) in the rat hypothalamus.

Pyroglutamyl-N3im-methyl-histidyl-prolineamide (methyl-thyrotrophin releasing hormone, methyl-TRH) is a potent synthetic analogue of TRH. N3im-Methyl-histidine is present in mammalian brain and it has been suggested that methyl-TRH is a physiological releasing hormone normally present in the hypothalamus. A non-gradient cation-exchange chromatography system that uses SP-Sephadex C-25 and completely resolves methyl-TRH and TRH has been developed. Because methyl-TRH cross-reacts in the immunoassay for TRH, this assay was used to measure TRH and methyl-TRH in the chromatographic fractions. By this means it has been demonstrated that the amount of methyl-TRH present in the rat is less than 0.025 ng/hypothalamus.


The efficiency and cost effectiveness of diagnostic tests for infectious mononucleosis.

The problem of diagnosis and appropriate treatment of patients presenting with pharyngitis is a common occurrence in family practice. The study of these patients includes laboratory tests to differentiate between infectious mononucleosis and other bacterial and viral infections. This study reviews the diagnosis of infectious mononucleosis in two large ambulatory populations, where different approaches were used. In one approach, all laboratory tests were concurrent, while in the other, serology was performed only after satisfaction of hematologic criteria for infectious mononucleosis. In the latter case, sequential use of laboratory tests resulted in a significant improvement in cost effectiveness. In both approaches, no appreciable gain was obtained from heterophil titers. Since the heterophil titer in confirmed cases of infectious mononucleosis does not correlate with prognosis or severity of the disease, this procedure can be replaced by the Monospot/"monoscreen" test alone.


Effect of trypsin inhibitors and concanavalin A on the fertilization of Bufo arenarum coelomic oocytes.

The effect of trypsin inhibitors (obtained from soybean, lima bean and ovomucoid) and Concanavalin A on fertilization in Bufo arenarum was tested. In order to study the effect of these substances at the level of the vitelline envelope of the oocytes, a new bioassay was designed. This bioassay employs coelomic oocytes to which some oviducal factors necessary for their fertility was added. Trypsin inhibitors block both the lytic effect of the acrosomal proteases on the vitelline envelope and fertilization. This indicates that the blockade of fertilization is a consequence of the inhibition of the lytic effect of the acrosomal proteases. Concanavalin A is effective as well in blocking the lytic effect of acrosomal proteases and fertilization. These effects are reversed by some sugar antagonists of the lectin, thus indicating that the effect of Concanavalin A is through its saccharide-binding capacity. These results suggested the involvement of glucosidic residues of the vitelline envelope in amphibian fertilization (the saccharide residues might be involved in the attack of the vitelline envelope by the acrosomal proteases). The possible mechanism of action of these substances is discussed.


Gradients of proliferation of ciliary basal bodies and the determination of the position of the oral primordium in Tetrahymena.

The pattern of proliferation of new basal bodies in ciliary rows (somatic proliferation) in Tetrahymena was observed. Starved and refed cells were used, because proliferation in these cells is more pronounced than that under other circumstances. The formation of new basal bodies is locally determined by the position of "old" pre-existing basal body (short range determination). However, the probability of proliferation associated with any given "old" basal body differs very much. This probability is determined by the spatial coordinates of the particular region of the cell (long range determination); however some randomness in this process was also observed. Two different gradients of proliferation were found. The first gradient is circumferential with a maximum number of new basal bodies added in ciliary rows n, 1, 2 and 3 and the minimum number added in ciliary rows 7, 8 and 9. The second is an antero-posterior gradient with the highest number of new basal bodies added in the midbody region. Moreover, at least in some cases, new oral primordia first appear, as a random proliferation of new basal bodies adjacent to a few old cilia of ciliary row No. 1, resembling somatic proliferation. Then 2,3 or even more clumps of basal bodies appear, each having one old cilium posteriorly. These clumps, however, are not linear groups within the ciliary row but instead they form small fields of basal bodies. These findings suggest, that the same two-gradient system for new basal body addition operates during somatic proliferation and also determines the position of the new oral primordium as the site of the highest gradient value at the intersection of two gradients.


Properties of chloride-stimulated 45Ca flux in skinned muscle fibers.

Isometric force and 45Ca loss from fiber to bath were measured simultaneously in skinned fibers from frog muscle at 19 degrees C. In unstimulated fibers, 45Ca efflux from the sarcoplasmic reticulum (SR) was very slow, with little or no dependence on EGTA (0.1-5 mM) or Mg++ (20 micrometer-1.3 mM). Stimulation by high [Cl] at 0.11 mM Mg++ caused rapid force transients (duration approximately 10 s) and 45Ca release. This response was followed for 55 s, with 5 mM EGTA added to chelate myofilament space (MFS) Ca either (a) after relaxation, (b) near the peak of the force spike, or (c) before or with the stimulus. When EGTA was present during Cl application, stimulation of 45Ca release was undetectable. Analysis of the time-course of tracer loss during the three protocols showed that when EGTA was absent, 16% of the fiber tracer was released from the SR within approximately 3 s, and 70% of the tracer still in the MFS near the peak of the force spike was subsequently reaccumulated. The results suggest that (a) the Cl response is highly Ca-dependent; (b) stimulation increases 45Ca efflux from the SR at least 100-200-fold; and (c) the rate of reaccumulation is much slower than the influx predicted from published data on resting fibers, raising the possibility that depolarization inhibits active Ca transport by the SR.


Evidence that the transmission of one source of scrapie agent to hamsters involves separation of agent strains from a mixture.

A previous paper (Kimberlin & Walker, 1977) described an experimental model of scrapie in hamsters in which the incubation period decreased progressively over the first 4 passages before becoming stable at the 5th and subsequent passes. Studies have been made of some of the agent strains present in brains taken from the 2nd, 3rd, 4th and 6th hamster passes. The results indicate the presence of at least two strains of agent at the 3rd passage level. One of these (431K) is highly pathogenic for mice and the other (263K) has an extremely low pathogenicity for mice. However only one of these strains (263K) is present in hamster brain after the 6th serial passage. It is suggested that the 'adaptation' of scrapie to hamsters may involve the selection, from a mixture, of a single strain which is highly pathogenic for hamsters. The possibility of modification of the properties of agent strains on passage discussed.


Therapeutic trials in muscular dystrophy. 1. Gold in murine dystrophy.

A trial of sodium aurothiomalate as an antiproteinase drug in the treatment of murine muscular dystrophy is reported. A blind controlled comparison of high (25 microgram/10 g body weight) and low dose gold (5 microgram/10 g body weight) with saline-injected control animals was made, all injections being given three times weekly. The body weights and functional ability of the mice were assessed at weekly intervals. No significant difference between the groups was observed. A trial of very high dose chrysotherapy (500 microgram of gold/10 g body weight) also showed no therapeutic benefit.


Neurofibrosarcoma of the radial nerve in von Recklinghausen's disease with metastatic angiosarcoma.

A case of von Recklinghausen's disease with multiple neurofibromatosis is described in which death was caused by intracerebral haemorrhage due to metastatic angiosarcoma. The primary site was a peripheral nerve tumour which, on microscopic examination, showed both angiosarcoma and neurofibrosarcoma with transitional zones between the two. This is interpreted as another example of divergent differentiation in malignant nerve sheath tumours, and the case is compared with the two similar examples found in the literature.


An ultrastructural study of subacute combined degeneration of the spinal cord in vitamin B12-deficient rhesus monkeys.

Prolonged deprivation of vitamin B12 in rhesus monkeys produced changes in the central nervous system that were indistinguishable topographically and histologically from those of human subacute combined degeneration. Ultrastructural studies of early lesions of the spinal cord disclosed a degeneration of myelin characterized by separation of myelin lamellae and formation of intramyelinic vacuoles, leading eventually to complete destruction of myelin sheaths. At a later stage, there was degeneration and loss of axons, and marked gliosis. The theories of pathogenesis of subacute combined degeneration are reviewed in the light of these observations.


Effect of load disturbances during centrally initiated movements.

1. We have investigated the relative contributions of mechanical and reflex mechanisms in generating the forces produced by the neck muscles when loads were unexpectedly applied during centrally programmed head movements in monkeys. These movements, subserved by muscles well endowed with muscle spindles, are part of the coordinated eye-head response to the appearance of a stimulus in the animal's visual field. Our preparation was a chronically vestibulectomized monkey trained to make a visual discrimination. 2. Two procedures were used to evaluate the torque generated by the neck musculature when an unexpected load disturbance was applied: first, by surgically interrupting the afferent loop subserving the reflex action (section of cervical dorsal roots) and second, by building a mathematical model of the head-neck system and carrying out a process of simulation. 3. Our results indicated that the compensatory torque of reflex origin stimulated by the application of an opposing force was less than 10--30% of that required for perfect compensation, and the larger fraction of the observed compensation was due to the mechanical properties (inertial, viscous, and elastic) of the neck musculature. The combined action of reflex and mechanical processes never completely compensated for the disturbance.


Color vision mechanisms in monkey striate cortex: dual-opponent cells with concentric receptive fields.

1. I have recorded with tungsten microelectrodes from single cells in the monkey's visual cortex and have specifically studied those neurons which were sensitive to the color of the stimulus. In the primate striate cortex there are four classes of color-coded cells. The cells described in this paper have concentric receptive fields with  one red-green opponent-color system in the field center and the opposite organization in the surround. These dual-opponent cells were nost sensitive to the simultaneous presentation of two different colors, one covering the field center and the other illuminating the surround. They are probable involved in the perception of simultaneous color-contrast phenomena. 2. Spectral sensitivity curves revealed that both the field centers and the surrounds received opposite types of inputs from red-sensitive and green-sensitive cones. None of the cells tested had inputs from rods. 3. Area-sensitivity curves showed that peripheral suppression was present for both phases of the center opponent-color system. The boundary between the center and the surround was the same for both sets of opponent systems. Some cells had "silent" surrounds, which did not respond to annular stimuli. 4. Multiple-unit recordings from a concentric cell and one of its presumed afferents yielded information regarding its possible synaptic inputs. In some cases the cells appeared to receive contacts from red/green opponent-color geniculated fibers with circular receptive fields that lacked an antagonistic surround (similar to Wiesel and Hubel's (37) type II class). In other instances the afferents had on-center, off surround receptive fields or the reverse, but received inputs from only one cone type, either red or green (similar to Wiesel and Hubel's type III class). 5. Concentric cells were always driven by only one eye. 6. The laminar distribution of these cells was limited almost entirely to layer IV and its subdivisions. 7. The cumulative evidence presented in this paper indicates that the concentric cells probably received direct geniculate inputs and, therefore, they are the first cortical stage in the integration of color-contrast information.


Correlation of neural discharge with pattern and force of muscular activity, joint position, and direction of intended next movement in motor cortex and cerebellum.

1. Monkeys were trained to grasp a rod movable in a horizontal arc (Fig. 1), and to hold the rod by angulation of the wrist in each of three positions (A,B, C). A maintained load was placed on the rod alternately to oppose flexion and extension. At a light signal, the monkey had to move to the next position in a prescribed sequence (ABCBABCBA, ETC.). The task was designed to dissociate, while holding in position, the following variables: 1) pattern of muscular activity in the forearm required to hold the wrist in position, determined by the direction of the load (flexor or extensor muscles); 2) position of the rod, and thus angulation of the wrist joint (A, B, and C); and 3) set for the direction of the intended next movement (flexor or extensor). These variables are subsequently referred to as MPAT, JPOS, and DSET, respectively. 2. After training, recordings were made of the EMG activity of muscles used in the task and of the discharge of single neurons in the motor cortex of the cerebrum and the interposed and dentate nuclei of the cerebellum. 3. While holding the wrist in position, EMG and interpositus behaved uniformly, with higher discharge frequency under load in one direction and lower discharge frequency under load in the opposite direction. This relation was relatively independent of the position held and of the direction of the intended next movement. Thus, interpositus and EMG both seemed best related to the MPAT variable, as opposed to JPOS and DSET variables. By contrast, neurons in motor cortex and in dentate fell into three categories: one category discharged in relation to the pattern of muscular activity (MPAT), a second to the position of the wrist (JPOS), and a third to the direction of the intended next movement (DSET). While MPAT neurons formed a distinct dissociated group, neurons that were best related to JPOS were often related to DSET, and vice versa. 4. A few of the MPAT neurons in interpositus and motor cortex were further studied by varying the magnitude (as well as the direction) of the loads. Both interpositus and motor cortex MPAT neurons changed firing frequency in relation to the magnitude of load, and though few neurons were thus studied, the relation seemed clearer for interpositus than for motor cortex. 5. Anatomically, the three types of neurons thus classified by firing pattern during the hold periods were intermixed in the arm area of motor cortex. In dentate and interpositus, those neurons thus related to the performance were localized to a narrow strip across the posterior part of both nuclei. Neurons apparently related to eye and drinking movements were located more posteriorly still, suggesting somatotopic representation.


Auditory nerve fiber response to wide-band noise and tone combinations.

1. Responses of single auditory nerve fibers to combinations of noise and tone were obtained. The results were found to depend on the relative effectiveness of each stimulus when presented alone. 2. When the response rate to one stimulus presented alone was considerably greater than the response rate to the other stimulus presented alone, the more effective stimulus dominated the responses when the two stimuli were combined. The more effective stimulus captured the response of the neuron. Thus, intense noise was found to mask responses to weaker tones, and intense tones were found to mask responses to weaker noise. This masking of the weaker stimulus is thought to enhance the signal-to-noise ratio of the most prominent response component. 3. When the two stimuli had similar effectiveness, complex interactions occurred. When the tone was near best (characteristic) frequency, partial summation effects occured. The tone partially suppressed the responses to the noise if other frequencies were used. Tones above best frequency caused particularly powerful suppression. 4. The bandwidth of the noise was varied somewhat. While bandwidth affected the effectiveness of the noise, it did not affect the types of interactions observed. 5. For a neuron which was essentially silent in the absence of acoustic stimuli, adding a weak level of noise lowered the threshold of responsiveness to the tone.


Role of primate flocculus during rapid behavioral modification of vestibuloocular reflex. I. Purkinje cell activity during visually guided horizontal smooth-pursuit eye movements and passive head rotation.

1. Extracellular recordings were obtained from 124 Purkinje cells (P-cells) in the flocculus of alert monkeys. P-cell simple spike-firing rate was analyzed quantitatively during various combinations of smooth-pursuit eye movement and passive head rotation. 2. During sinusoidal smooth eye movements, 80% of the P-cells displayed increased firing rate during ipsilateral and 20% during contralateral eye movement. Over the frequency range 0.3--1.4 Hz, firing-rate modulation was proportional to and in phase with maximum eye velocity. During the steady state of triangle-wave tracking, firing rate increased monotonically as a function of eye velocity. Since firing rate was uncorrelated with retinal-error velocity, one component of P-cell firing rate was related to eye velocity. 3. During the transient phase of triangle-wave tracking, when an instantaneous change in the direction of target movement caused a large retinal-error velocity, 40% of the P-cells were related only to eye velocity. Sixty percent of the P-cells displayed an overshoot or undershoot in firing rate, indicating a relationship to either retinal-error velocity or eye acceleration as well as to eye velocity. 4. During the vestibuloocular reflex (VOR), evoked by head rotation in the dark, P-cell firing rate was only weakly modulated. In contrast, when the monkey suppressed the VOR by fixating a target that rotated with him, P-cell rate was deeply modulated. Since the modulation was proportional to and in phase with maximum head velocity, another component of P-cell firing rate was related to head velocity. 5. Of 36 P-cells tested, 35 displayed firing-rate modulation during both suppression of the VOR and smooth-pursuit eye movement. P-cells that reached peak firing rate during ipsilateral head rotation also reached peak firing rate during ipsilateral smooth eye rotation. Average population sensitivitites to head velocity and eye velocity were equal. In three conditions in which eye and head velocity were elicited simultaneously, P-cell firing rate could be predicted by the linear, vector addition of the separate eye and head velocity components of firing rate. Therefore, the relatively weak modulation of P-cell firing rate during the VOR in the dark can be accounted for by the cancellation of equal but opposite head and eye velocity components. 6. The connections of flocculus P-cells to interneurons in the brain stem VOR pathways have been established in other mammals. In the context of those connections, P-cell firing patterns were appropriate to facilitate the eye movements the monkey was required to make. We conclude that the flocculus is important for sustaining any smooth eye movements that are different from those evoked by head rotation in the dark. The eye velocity component may represent an efference copy signal that sustains ongoing eye velocity during smooth pursuit.


Role of primate flocculus during rapid behavioral modification of vestibuloocular reflex. II. Mossy fiber firing patterns during horizontal head rotation and eye movement.

1. Extracellular recordings were obtained from 113 mossu fibers (MFs) in the flocculus of alert monkeys trained to perform a visual tracking task during sinusoidal, horizontal head rotation. The analysis of MF discharge patterns was designed to allow quantitative comparison of the discharge properties of flocculus MFs with brain stem cell populations from which the MFs might originate and with flocculus Purkinje cells (P-cells). Based on their firing patterns, MFs were divided into two classes. Vestibular MFs discharged in relation to head velocity and, in some cases, also in relation to eye movement. Eye movement MFs discharged only in relation to one or more components of eye movement. 2. Vestibular MFs were subdivided into three classes. Vestibular-only MFs (n = 15) displayed a modulation in firing rate during head rotation but exhibited no relationship to spontaneous eye movements. Vestibular-plus-saccade MFs (n = 14) displayed a modulation in firing rate during head rotation that quantitatively resembled the modulation in vestibular-only MFs. In addition, a pause in firing rate interrupted the vestibular modulation during saccades in one or more directions. Vestibular-plus-position MFs (n = 4) exhibited steady firing rates that were linearly related to horizontal eye position in the absence of vestibular stimulation. Sinusoidal head rotation evoked a modulation ofiring rate above and below the firing rate set by the eye position. 3. during sinusoidal head rotation, vestibular MF firing rate led head velocity by an average of 24 degrees. The amplitude of MF firing-rate modulation increased as a function of the frequency of head rotation and, hence, maximum head velocity. Since these characteristics are similar to those displayed by P-cells during suppression of the VOR, vestibular MFs probably transmit the head velocity component of P-cell firing rate to the flocculus. Based on evidence from other mammals and a quantitative comparison of population discharge characteristics, it is likely that vestibular MFs originate from the vestibular nerve and from cells in the medial vestibular nucleus. 4. Based on their discharge patterns, eye movement MFs were also subdivided into three classes. Burst MFs (n = 14) emitted a high-frequency burst of spikes prior to and during saccades in one or more direction, but were silent during steady fixation. Burst-tonic MFs (n = 53) emitted a burst of spikes prior to saccades in a preferred ("on") direction, ceased firing during saccades in the opposite ("off") direction, and exhibited steady firing rates that increased as steady gaze shifted in the on direction. Tonic MFs (n = 13) displayed steady firing rates that increased as the position of steady gaze shifted in the on direction, and either paused or exhibited step changes in firing rate during saccades. 5. During steady fixation, 64% of tonic and burst-tonic MFs were recruited into maintained firing within +/- 10 degrees of the primary direction of gaze...


Functional specificity of lateral geniculate nucleus laminae of the rhesus monkey.

1. This study investigated the functional specificity of the lateral geniculate mucleus (LGN) of the rhesus monkey using microelectrode-recording techniques. 2. The parvocellular laminae of the LGN receive input predominantly from medium-conduction-velocity optic tract fibers, while the magnocellular laminae receive fast-conducting axons from the retina. 3. Cells projecting from the parvocellular layers to area 17 have medium-conduction velocities, while those from the magnocellular layers are fast conducting. 4. The majority of cells in the parvocellular layers have a concentric color-opponent receptive-field organization. The receptive fields of magnocellular layers cells are also concentrically organized, but their center-surround organization is independent of wavelength. 5. Responses in the parvocellular layers are more sustained than in the magnocellular layers. 6. Cells in the dorsal pair of parvocellular layers are predominantly on-center. In the ventral pair of parvocellular layers, most cells are off-center. 7. Blue-selective cells are found predominantly in the ventral pair of parvocellular layers. All of these found gave on-responses to blue stimuli.


Direct administration of methotrexate into the central nervous system of primates. Part 1: Distribution and degradation of methotrexate in nervous and systemic tissue after intraventricular injection.

Levels of methotrexate (MTX) measured by both 3H radioactivity and dihydrofolate reductase assays were determined in cerebrospinal fluid (CSF), plasma, urine, and both neural and non-neural tissues at varying times after a single intraventricular injection into Cynomolgus monkeys (Macaca fascicularis). Clearance of the MTX from CSF was rapid after injection. A relatively constant level of 3HMTX was reached in plasma 2 1/2 hours after injection, and about 30% of the 3HMTX dose was excreted in the urine within 4 hours after injection. Maximum levels in CNS tissues were obtained by 4 hours after injection, and average concentrations of 10(-6) M MTX (moles/kg wet weight) were maintained in CSF for up to 12 hours and in brain for up to 24 hours after injection. Conversion of MTX to non-MTX products was detected in CSF between 4 and 12 hours, and in brain tissue between 12 and 24 hours after injection, and the amount of these products increased with time. Regional distribution studies in the cerebrum showed a U-shaped distribution curve for 3HMTX up to 12 hours after injection, which closely followed the 14C inulin distribution. Thus, the levels in deep cerebral tissue were less than the average level for brain, and this suggests that treatment of CNS tumors by intraventricular injection may have variable results, partly due to complex tissue distribution patterns.


Direct administration of methotrexate into the central nervous system of primates. Part 2: Distribution of 3H methotrexate after intrathecal lumbar injection.

The kinetics of distribution of 3H methotrexate (3HMTX) in the central nervous system, plasma, and urine after intraventricular, lumbar percutaneous puncture, and spinal catheter injections were compared. Levels of 3HMTX in whole brain after lumbar percutaneous injection were 40 times less than after intraventricular injection. Injection of 3HMTX via a spinal catheter increased the level of 3HMTX in whole brain but this was still tenfold less than after direct intraventricular instillation. Also, it was found that a disproportionately high amount of 3HMTX was in the brain-stem-cerebellum region which would further reduce the concentration of methotrexate in the cerebral hemispheres. Both intraventricular and lumbar spinal catheter administration of 3HMTX produced 3HMTX levels greater than 10(-6)M (moles/kg wet weight) in spinal cord tissue as measured by 3H specific activity between 2 to 8 hours after injection. Administration by lumbar percutaneous puncture, however, rarely resulted in this suggested therapeutic level of 10(-6)M. Initial 3HMTX levels in plasma after lumbar percutaneous instillation was 24 times greater than after intraventricular or lumbar spinal catheter injections. This indicated significant and unavoidable extradural leakage after lumbar percutaneous puncture, which may account for the substantially lower levels of 3HMTX in the brain and spinal cord tissue. It is concluded that intraventricular instillation of methotrexate is the best route of administering the drug to achieve therapeutic levels of methotrexate in both whole brain and throughout the spinal cord.


Lumbosacral intradural periradicular ossification. Case report.

Intrathecal ossification causing progressive myelopathy or radiculopathy does not occur frequently. The majority of the reported lesions have been in the thoracic spine and seldom in the sacral canal. This report presents the occurrence of disabling low backache and sciatica from intradural periradicular ossification in the lumbosacral region in a previously healthy man.


Cerebral arterial responses to induced hypertension following subarachnoid hemorrhage in the monkey.

Regional cerebral blood flow (rCBF), angiographic cerebral arterial caliber, and cerebrospinal fluid (CSF) pressure were measured in rhesus monkeys to determine the effect of experimentally induced subarachnoid hemorrhage (SAH) on cerebral arterial responses to graded increases in blood pressure. These measurements were also performed in a control group of monkeys subjected to a mock SAH by injection of artificial CSF into the cerebral space. Before subarachnoid injection of blood or artificial CSF, graded increases in mean arterial blood pressure (MABP) to a level 40% to 50% above baseline values had no effect on rCBF. The major cerebral arteries constricted and CSF pressure remained unchanged. Similar responses were observed after injections of artificial CSF. When MABP was increased in animals that had been subjected to subarachnoid injection of blood, rCBF increased and was associated with dilatation of the major cerebral arteries and moderate increases in CSF pressure. These results demonstrate that cerebral arterial responses to increases in blood pressure may be abnormal in the presence of subarachnoid blood. The manner in which abnormal cerebral arterial reactivity, changes in blood pressure, and vasospasm combine to determine the level of cerebral perfusion following SAH is postulated.


L-alanyl-L-tyrosine as a tyrosine source during intravenous nutrition of the rat.

Tyrosine is considered an essential amino acid for some premature infants, but its limited solubility prevents addition to intravenous solutions in adequate amounts. Tyrosine peptides with solubilities greater than tyrosine were synthesized to evaluate potential for intravenous use. Intraperitoneal injection of L-alanyl-L-[U-14C]tyrosine (0.5 mmoles/kg) into adult rats resulted in a rapid labeling of tissue pools and production of 14C-CO2. When the peptide was infused as part of an intravenous nutrition solution (0.5 mmoles/kg/24 hours) into adult rats, plasma and tissue tyrosine pools were rapidly labeled. The radioactivity distribution after 24 hours of infusion was: 41% CO2, 13.4% muscle, 7.7% urine, 7.1% liver, 5.5% intestine, 1.4% kidney, with the remainder in other carcass organs. No unhydrolyzed peptide was found in tissue homogenates. Between 9% and 17% of the radioactivity present in tissue was free tyrosine, with the remainder in tissue protein. Tyrosine accounted for more than 96% of this protein bound radioactivity. The data indicate good utilization of alanyl-tyrosine as a tyrosine source when administered intravenously.


Polyanomalodontia.

Reported is a case of multiple anomalies in dental morphology. The morphological anomalies comprised macrodontia, multituberculism, invaginations, and single conical molar roots. The gross morphological, radiological, histological and ultrastructural findings are presented and compared to similar forms of multiple anomalies in dental morphology.


Ultrastructural study of tumor cell differentiation in osteosarcoma of jaw bones.

Tw osteosarcomas of jaw bones have been studied by electron microscopy. The objectives were to examine the specific cell types in relation to functions and ultrastructural features, and to examine matrices produced by tumor cells. The osteosarcoma cells were subdivided into four cell types: anaplastic, chondroblastic, osteoblastic, and osteocytic--giant cells were not considered in the present investigation. Compared to normal bone cells, no specific sign of malignancy was found. However, tumor cells seem to lose functional abilities, i.e. a modification of matrix. Consequently, tumor matrix has altered organic and inorganic components with impairment of collagen maturation and matrix mineralization. The alteration in both processes may be related to a diminished production of proteoglycans. The cytogenic hypothesis of a tumor stem cell may be supported by the identification of anaplastic osteosarcoma cells resembling immature reticulum cells. One may speculate on transformation of this cell type as a genetically predetermined osteoprogenitor cell of malignant potential.


Vitamin A deficiency and new bone growth: histologic changes.

Using a standardized guinea pig model system, the histologic appearance of newly formed bone from vitamin A deficient, vitamin A adequate and retinoic acid treated animals was compared. Microscopic examination of the histologic sections of bone collected from vitamin A deficient guinea pigs indicated the presence of highly cellular and loosely woven bone spicules. This model system is an osteoblastic model, since osteoclasts are essentially absent in tissue formed in 14-day implants. Thus, new bone formation in the vitamin A deficient guinea pig reveals morphologic changes which are principally mediated through the osteoblastic process.


Neurofibromatosis and childhood leukemia.

Twelve new cases of childhood leukemia and neurofibromatosis were ascertained and evaluated in conjunction with 17 previously well-documented cases. The ratio of ALL:nonlymphocytic leukemia was 9:20, markedly different from the 4:1 ratio in children without NF. Rarer subtypes predominated: 8 CML and 8 AMML. The peculiar distribution of leukemia by cell type and the number of cases observed in the United States indicate that the risk of childhood leukemia in NF is increased. Two possible variants were noted: NF with "transient leukemia," and multiple skin xanthomas with nonlymphocytic leukemia.


Thyroid function in healthy premature infants.

Thyroid function was studied in healthy premature and term infants between 12 hours and 3 months of age. T4 and FT4I followed parallel courses in both groups; during the first 45 days, however, the values were significantly lower in premature infants under 34 weeks' EGA than in term infants (P less than 0.001). The post-delivery peak in TSH concentration (mean +/- SD) was 71.8 +/- 19.2 microunits/ml in the premature infants. In five premature infants, injection of TRH elicited a TSH increment of 29.4 +/- 20.7 microunits/ml at 30 minutes. T3 concentration was not significantly different in premature and term infants.


Lipid metabolism in the neonate. III. The ketogenic effect of Intralipid infusion in the neonate.

The ketogenic potential of Intralipid was studied in two groups of infants: 12 were SGA and 15 AGA; all were clinically stable and less than 48 hours of age. During four-hour Intralipid tolerance tests, the SGA infants achieved significantly higher plasma TG and FFA levels. Both groups of infants significantly increased the concentration of ketone bodies; however, there was no difference in the levels achieved. In view of the slower clearance rate of TG and the higher levels of FFA in SGA infants, it is speculated that in addition to a possible defective lipoprotein lipase system and a decrease in number and size of the adipose cells, beta-oxidation of FFA to ketones may be occurring at a slower rate. The generation of high levels of ketones during Intralipid infusion period in both groups of infants indicates that SGA infants can handle ketone bodies as readily as AGA infants.


Tissue tropism of different Trypanosoma cruzi strains.

A systematic study of the distribution of intracellular parasites in the organs and tissues was performed in groups of mice inoculated with 4 different Trypanosoma cruzi strains. An extremely high parasitism of spleen, liver, and bone marrow was observed in mice inoculated with Y and Berenice strains; with CL strain, however, parasites were almost absent in those organs. Bloodstream forms apparently present differences which facilitate or prevent their uptake by macrophages from the mononuclear phagocytic system. Parasitism of the smooth muscle from hollow organs was significantly higher with ABC and Berenice strains than with Y and CL. The importance of the distribution of intracellular stages in the pathogenesis of the disease is discussed.


Studies on the Burma (Thau.) strain of Plasmodium falciparum in Aotus trivirgatus monkeys.

The Burma (Thau.) strain of Plasmodium falciparum was established in 3 Aotus trivirgatus monkeys by the inoculation of parasitized blood from man. Subsequently, passage from monkey to monkey was obtained through subinoculation of blood parasites to 15 Aotus monkeys. Anopheles freeborni mosquitoes were fed on these infections on 207 occasions; in 105 of these trials, mosquitoes became infected. A total of 335 (9.9%) of the 3,378 individual mosquitoes dissected were infected. Passage of the infection by the bites of infected A. freeborni was attempted on 7 occasions; 4 of these transmission attempts were successful with prepatent periods ranging from 19 to 69 days.


Methods for storage of antimicrobial effectiveness test inoculum suspensions below freezing.

Studies were conducted to determine the suitability of storage below freezing of some antimicrobial effectiveness test inoculum organisms: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. Several solutions used for protecting microorganisms subjected to storage below freezing were compared. Comparison of 10% dextrose with other solutions (distilled water; 0.07 M phosphate buffer, H 7.0, with 15% glycerol; and 0.07 M phosphate buffer, pH 7.0, with 7.5% dimethyl sufoxide) demonstrated that inoculum suspensions were most stable when prepared with 10% dextrose. After storage for 6 months at-50 degrees in a freezer, inoculum suspensions prepared with 10% dextrose retained viability and demonstrated suitability for use in antimicrobial effectiveness tests of dosage forms containg preservatives.


Pharmacokinetics of iodoxamic acid in rhesus monkey: biliary excretion, plasma protein binding, and enterophepatic circulation.

The previously reported steady-state method allowed estimation of the capacity-limited pharmacokinetics of the cholangiographic agent, iodipamide. To circumvent the long time period required to establish each steady-state level, a dynamic method was applied to the study of the rate processes involved in the hepatic uptake and biliary excretion of a new cholangiographic agent, iodoxamic acid, in rhesus monkeys. The dynamic method has the advantage that the pharmacokinetic parameters involved in capacity-limited hepatic uptake or biliary excretion can be obtained from a single infusion experiment. The V max was 1.03 +/- 0.25 mumoles/kg/min (mean +/- SD); Km varied from animal to animal and ranged from 1.5 to 16.4 micrometer. Protein binding was estimated using equilibrium dialysis. The Freundlich isotherm yielded a linear plot when the natural logarithm of unbound iodoxamic acid concentration in plasma was plotted against the natural logarithm of its blood concentration. The plasma protein binding data also could be fitted to the Langmuir isotherm, presuming two independent classes of binding.


The placental transfer and materno-fetal disposition of methadone in monkeys.

A method is described for the quantitation of levo-methadone[3H] in biological samples which involves sample extraction and thin-layer chromatographic separation. Four pregnant Macaca mulata monkeys, two in early gestation and two in late gestation, were given single i.m. injections of levo-methadone[3H]. Twenty-nine fetal and maternal tissues and fluids were assayed to provide quantities of unchanged methadone and methadone plus metabolites. Little placental transfer of methadone or its metabolites occurred during early gestation, but equivalent concentrations of unchanged methadone were found in maternal and fetal tissues during late gestation (maternal brain, 172 ng/g; fetal brain, 123 ng/g). With few exceptions, tissues or fluids from the late gestation mothers showed higher levels of unchanged methadone than those from early gestation mothers at both 1 hour (P less than .001) and 6 hours (P less than .010) after administration. The late gestation mother had a 40.2% greater concentration of unchanged methadone at 6 hours and a 50.1% greater concentration at 1 hour than the early gestation mothers. These data suggest a slowing of metabolism during advanced pregnancy. At 6 hours after administration the eyes of both early and late gestation mothers and late gestation fetuses showed the highest concentrations of unchanged methadone of any maternal or fetal tissue. This localization of methadone appears to be associated with pigmented epithelium.


Hemodynamic effects of systemic and central administration of alpha-methyldopa.

Systemic and regional hemodynamic changes were measured in five restained conscious rhesus monkeys before and after a 2-hour intravenous infusion of 50 mg/kg of alpha-methyldopa and, in another group of five monkeys, 5 to 10 mg injected into a lateral cerebral ventricle. Both routes of administration evoked similar degrees of hypotension, bradycardia and decreased cardiac output, although  the cerebral intraventricular (i.c.v.) injections had more immediate and long-lasting effects. Both groups had a similar pattern of changes in the redistribution of cardiac output and blood flow that lasted at least 4 hours. Blood flow was maintained in the hepatic and renal arteries and decreased in skeletal muscle, heart, brain and skin. In contrast, i.c.v. injections of alpha-methyldopamine and alpha-methylnorepinephrine given at the same site evoked dose-related pressor responses that lasted up to 4 hours. The data suggest that alpha-methyldopa has important central action that inhibits sympathetic outflow, but that its hypotensive effect is either mediated only by endogenously formed metabolites or that its mechanism of action is not directly related to these metabolites at sites around the lateral and third cerebral ventricles in the monkey.


Paradoxical effects of cobaltous chloride and salts of other divalent metals on tissue levels of reduced glutathione and microsomal mixed-function oxidase components.

Treatment of animals with cobaltous chloride caused decreases in hepatic, pulmonary and renal cytochrome P-450, and alterations in levels of other components of microsomal mixed-function oxidases, which can alter the rate of biotransformation of certain drug substrates. The treatment also caused a striking, dose-dependent elevation in tissue levels of reduced glutathione (GSH), within 2 to 8 hours. The effect of cobalt on GSH occurred in all tested animal species and strains. Actinomycin-D partially prevented the cobalt-stimulated rise in hepatic GSH. Salts of several other divalent metals also produced sharply elevated levels of hepatic GSH, occurring concomitantly with decreased microsomal content of cytochrome P-450. These results suggest that pretreatment of animals with cobaltous chloride, or other divalent metal salts, could alter the disposition of certain toxic, alkylating drug metabolites not only by decreasing the rate of formation of the reactive metabolites, but also by increasing the amount of GSH available for the formation of their less reactive, less toxic, GSH conjugates.


Transformation in Tetrahymena pyriformis: description of an inducible phenotype.

Transformation of Tetrahymena pyriformis to a rapid-swimming (presumably dispersal) form can be induced by washing cells and suspending them in distilled H2O, Dryl's solution or 10 mM Tris. Transformation is possible with high efficiency in mass cultures of axenically grown cells within approximately 5 h at 30 C. The radically different phenotype produced during transformation is characterized by a more elongate body form, increased numbers of somatic basal bodies and cilia, a long caudal cilium and oral membranelles positioned beneath the cell surface. DNA quantities characteristic of G1, S, and G2 cells are found in these transformed ciliates, suggesting that achievement of a particular stage in the DNA-division cycle is not a prerequisite for transformation. Preliminary observations on cells belonging to syngens 2-12 indicate that they also have a capacity to form a caudal cilium, but that the amicronucleate strain GL-C does not. Possible relevance of the transformed phenotype for taxonomy of Tetrahymena is discussed.


Mitomycin antibiotics. Synthesis of 7-methoxy-1-(N-pyrrolidino)mitosene and its methiodide.

7-Methoxy-1-(N-pyrrolidino)mitosene and its methiodide were synthesized. The latter compound was a potential bifunctional alkylating agent because of its two good leaving groups appropriately situated with respect to the indoloquinone chromophore. However, it was inactive in bacteriophage induction and P388 murine leukemia assays. Both compounds showed antibacterial activity in culture, and the former compound was very weakly active in inducing lysogenic bacteriophage.


Experimental studies of the pathogenesis of Pseudomonas aeruginosa infection: evidence for the in-vivo production of a lethal toxin.

Evidence is presented that a lethal toxin is produced by P. aeruginosa growing in the burned skin of experimental mice. After injection of approximately 100 P. aeruginosa cells into the burned skin there was a rapid proliferation of organisms at the site of inoculation. When the organisms in the burned skin tissue reached a critical concentration, there was generalised toxaemia with subsequent mortality; the process was not reversible at this stage, even by reducing substantially the numbers of infecting organisms. However, when the reduction was accompanied by administration of rabbit serum prepared against filter-sterilised extracts of infected burned tissues, approximately 40% of the animals survived for at least 96 h. The data suggests that the antiserum afforded protection by inactivating a toxin produced by the organisms growing in the infected burned tissues rather than by further reducing the numbers of infecting organisms.


Experimental infections with protease-deficient mutants of Pseudomonas aeruginosa in mice.

The virulence of a protease-producing strain of Psuedomonas aeruginosa was compared with that of mutants that had lost the ability to produce proteases and other extracellular enzymes. Lethal infections were produced by inoculating mice intraperitoneally with bacteria in mucin, or by inoculating mice intraperitoneally or intravenously with bacteria 4 days after treatment with cyclophosphamide, 200 mg per kg body weight. No significant difference in virulence between the wild-type parent strain and some of its protease-deficient mutants was found. Histopatholoical examination of different organs in the cyclophosphamide-treated and infected mice showed striking fatty infiltration and focal necrosis of liver, multiple necrotic foci in the spleen and haemorrhagic cystitis with necorsis. The cystitis was produced by cyclophosphamide alone but was aggravated by the infection. In conclusion, no correlation between the production of protease in broth culture and the ability to produce lethal septicaemia in mice was found, and extracellular proteases probably didnot contribute to the virulence of P. aeruginosa. However, the histopathological changes in the liver suggested a role for exotoxin A insystemic infections.


Comparison of several culture media used for studies on mycobacteriophages.

The value of RVA, N-1, 7H10, 7H11 and Sauton's media for studies on mycobacteriophage infeciton and lysis of mycobacteria was assessed. Experiments were made with mycobacteriophages BGI, BKI, CRI-3, G37, and LG, all of which lyse Mycobacterium smegmatis strain 607B, and with mycobacteriophage DS6A which lyses Mycobacterium tuberculosis strain H37Rv. The methods involved "direct lysis", the measurement of "routine test dilutions" and counts of plaque-forming units. It was found that N-1, 7H10 and 7H11 media gave better overall results than RVA medium for M. smegmatis strain 607B and its phages, and that RVA medium was generally the most useful for M. tuberculositems employed.


Fibrinolytic activity associated with established lymphoblastoid cell lines and fresh peripheral blood lymphocytes of human and nonhuman primate origin.

Established lymphoblastoid cell lines and normal peripheral blood lymphocytes were examined for their ability to induce fibrinolysis, a property associated with oncogenic transformation, using a 3H-fibrin plate technique. Fibrinolytic activity showed serum preferences with dog serum being most active. Most cell lines (14/18) induced greater than 40% release, while normal lymphocytes were generally less active. Only one cell line tested released plasminogen activator into the medium. No correlation was shown between fibrinolytic activity and growth in soft agar. Normal rhesus lymphocytes showed fibrinolytic activity in B cell-enriched populations with no evidence of interaction between B cells and T cells.


Photic and pentylenetetrazol-induced seizure susceptibility in Macaca mulatta.

Ninety-five out of 100 male Macaca mulatta of varying ages from a restricted habitat in N. India showed no abnormal seizure susceptibility or EEG response to photic stimulation and no electro-clinical features of epilepsy after pentylenetetrazol, 40 mg/kg sc.c. Autopsy studies on the remaining five monkeys with increased seizure proneness revealed depressed skull fractures with cortical trauma in four and a neoplasm in one. Presumably, these factors were responsible for the lowered seizure susceptibility to photic stimulation and pentylenetetrazol activation.


Genital Ureaplasmas in nonhuman primates.

Ureaplasmas were isolated from the genital tracts of four of 22 (18.4%) male chimpanzees and eight of 23 (34.8%) female chimpanzees. Twenty-nine female rhesus monkeys, 38 female baboons, one gibbon, and black ape and one Java monkey were shown to be free of genital Ureaplasmas. The rate of reproductive failure among the chimpanzees was high and it is suggested that Ureaplasma may be responsible in part. The chimpanzee may serve as a useful model for human Ureaplasma genital infections.


Plasma amine oxidase activity in 136 normal rhesus monkeys: relationships between enzyme activity and age, sex and genetic factors.

Normative data on plasma amine oxidase activity were obtained for four primate species, M. mulatta, M. arctoides, C. aethiops and H. sapiens. Significant between-species differences in activity were observed. In a large sample of M. mulatta, no significant relationship between age and plasma amine oxidase activity was observed, but adult males had significantly higher enzyme activities than adult females.


Comparative metabolism of the amphetamine drugs of dependence in man and monkeys.

The use of animal models to study drug dependence and tolerance requires that the species used metabolizes the drugs like man, a condition frequently not fulfilled by non-primate species. The metabolic fate of several amphetamine drugs, namely amphetamine, norephedrine, chlorphentermine and phenmetrazine, in the rhesus monkey and the tamarin and two non-primate species has been investigated and compared to that found for man. The findings show that the two primate species metabolize these drugs in a manner similar to that in man.


Closed needle liver biopsy for assessment of monooxygenase activity in rhesus monkeys (Macaca mulatta).

Closed needle liver biopsy routinely provides 60-100 mg tissue from rhesus monkeys (Macaca mulatta). No mortality or morbidity was observed in over 400 needle biopsies during a two-year period in which some monkeys were biopsied over 30 times. Biopsy tissue was used as enzyme source in low-volume in vitro systems for measurement of hepatic monooxygenase activity.


The pyramidal system of the cat and of the monkey: neurophysiologic aspects of phylogenetic advancement.

The pyramidal motor system underwent dramatic phylogenetic developments. Ethologically, this has found expression in higher capacities for accurate movements. An hypothesis and supporting data are offered that this depends on the advancement in the higher species of a system based on the attainment of higher accuracy by an increase in the number of channels, an increased range of conduction velocity values, an increase in surround effects of the PTN and the evolvement of a stochastically based mechanism the accuracy of operation of which depends at least on the above-mentioned factors.


Dysgerminoma in a rhesus monkey: morphologic and biological features.

A female Macaca mulatta was observed for 31 months after the initial surgical removal of an ovarian tumor. Solitary metastatic lesions were surgically removed 26 and 28 months after excision of the primary tumor. The animal was killed after 31 months because of additional metastatic lesions. Histological evaluation by light microscopy was not conclusive in determining the origin of neoplasm. Transmission electron microscopy, lymphocyte marker studies, and hormone assays were utilized to confirm the diagnosis of dysgerminoma.


Pregnancy diagnosis in squirrel monkeys: hemagglutination test, radioimmunoassay, and bioassay of chorionic gonadotropin.

The Nonhuman Primate Pregnancy Test may be useful for diagnosis of pregnancy in squirrel monkeys between 40 and 60 days in pregnancy. However, single determinations have an inherent 10% risk of false negative responses caused by low chorionic gonadotropin levels; thus, initial negative test responses should be followed within one week by an independent confirmatory test. Preliminary results with this hemagglutination inhibition test compare favorably with bioassay and may be useful, in conjunction with conventional uterine palpation, for diagnosis of pregnancy in squirrel monkeys.


Red cell and serum enzymes of Guinea baboon (Papio papio).

Variants of some erythrocyte and serum enzymes have been studied among several blood samples of Guinea baboon (Papio papio). Variation occurred in two red cell enzymes, G6PD and NADH diaphorase, and in serum esterase. All studied animals had a complete uniformity in other enzyme systems (acP, 6PGD, CA, AK, and cholinesterase at E1 locus). Data obtained in the present work have been discussed and compared with those reported among other baboon species.


Biological and artificial ion exchangers: electrical measurements with glass microelectrodes.

Biological (stratum corneum) and artificial (cation-exchange resin beads, Bio-Rad AG 50W-X2) ion exchangers were impaled by glass microelectrodes filled with KCl solution. The electrical potential difference recorded in these structures in reference to the external bathing medium was shown to be dependent on the KCl concentration of both the external and the microelectrode filling solutions. The potentials were interpreted on the grounds of the fixed charge theory of membrane potentials as a consequence of two phase boundary potentials (Donnan potentials), one at the matrix-external solution interface and the other at the matrix-microelectrode solution interface. The contribution of a diffusion component for the recorded potential was considered.


Cellular changes in the toad urinary bladder in response to metabolic acidosis.

The urinary bladder of Bufo marinus excretes H+ and NH+4, and the H+ excretion is increased when the animal is placed in metabolic acidosis. The mitochondria-rich (MR) cells mediate the H+ excretion by the bladder. The purpose of this study was to determine if there is a change in MR cells of the bladder during metabolic acidosis. Bladders from normal toads and from toads that had been placed in metabolic acidosis were used. The bladders were mounted between plastic chambers and H+ excretion measured. The bladder was then fixed and prepared for scanning (SEM) and transmission (TEM) electron micrograph studies. SEM's at low magnification were used to count the various cell types and the TEM's were used to confirm the different cell types. Fields were randomly selected and a total of 2500 cells counted in each group. The bladders from toads in metabolic acidosis had a consistently higher ratio of MR cells to granular cell than did the normal bladders. These results indicate that during metabolic acidosis there is an increased number of MR cells in the bladder, and this increased the bladder's capacity to excrete H+.


Evidence for involvement of microtubules in the action of vasopressin in toad urinary bladder. II. Colchicine binding properties of toad bladder epithelial cell tubulin.

Colchicine, podophyllotoxin and vinblastine have been found to inhibit the action of vasopressin on water movement in the toad urinary bladder. Tubulin is the major colchicine binding component of toad bladder epithelial cells, accounting for approximately 3.3% of the total cell protein. More than 99% of the tubulin is found in the soluble fraction after sonication, the remainder is in the particulate fraction. Similar to the characteristics of the binding of colchicine to tubulins from other sources, the binding of colchicine to toad bladder tubulin is temperature- and time-dependent, is inhibited competitively by podophyllotoxin (Ki= 5.5 x 10(-7)m), and has a binding constant of 1 X 10(6) liters/mole at 37 degrees. Binding activity decays according to first-order kinetics and is stabilized by vinblastine. The characteristics of the interactions of colchicine and podophyllotoxin with epithelial cell tubulin in vitro closely parallel the ability of these drugs to inhibit the response to vasopressin in vivo. These results, coupled with those of functional and morphological studies, support the view that the ability of these drugs to affect vasopressin-induced water movement across toad bladder epithelial cells is related to the depolymerization of cytoplasmic microtubules.


An evaluation of surgical and conservative treatment of fractures of the ankle in 200 patients.

The longterm results of surgical and conservative treatment in two almost identical groups of patients with fractures of the ankle have been analyzed. The results were better after conservative treatment; delayed operation and repeated manipulations were found to be the main reason for the poorer postoperative results, especially in elderly osteoporotic patients. The damage consequent to repeated manipulations, the difficulties resulting from delaying operation, and the advantages of early open reduction are discussed. It may be that under certain conditions of unavoidable delay, a mild residual displacement should be accepted rather than repeated manipulation and delayed open reduction. It is concluded that, when indicated, operations should be performed as early as possible after injury, probably giving the best end results as evidenced by the preliminary findings of a prospective study currently under way.


Progesterone and glucocorticoid in relation to the growth and differentiation of mammary epithelium.

In pursuit of a model system in which to determine whether exposure to progesterone is necessary for mammary epithlial cells to develop their differentiative potential, hormone-dependent growth of the mammary epithelial rudiment in adult male mice has been reexplored. The formation of ductal cells can be effected by administration of estradiol in the absence of endogenous progesterone and glucocorticoid, using adrenalectomized-castrated animals. The resulting epithlium contains three times more lactose synthetase activity, per epithelial cell, than that in midpregnant mice. The blood spermidine level in these doubly operated animals was similar to the concentration of spermidine required to substitute effectively for glucocorticoid during mammary differentiation in vitro, It is suggested that spermidine can partially supplant glucocorticoid in vivo in milk protein synthesis. It is also concluded that, unlike other secondary sex tissues, mammary cells do not require exposure to progesterone during their ontogeny in order to realize their differentiative potential. The positive role of this steroid in mammary development is apparently limited to its effect on the formation of alveolar structures.