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Biomedical subjects

C Gottlieb

Publications and source records attributed to C Gottlieb.

At least 73 records · Page 4Linked to original sources
PubMed1987

Role of prostaglandins in human reproduction: recent advances.

Our knowledge of the importance of PGs for the physiological regulation of male and female reproductive organs is rapidly increasing. In this presentation two examples have been described in detail. Data are accumulating indicating that PGs in semen are of major importance for sperm motility and the functional capacity of sperms. Recording of intrauterine pressure in early pregnant patients has shown that treatment with an antiprogestin depriving the myometrium from progesterone influence, will induce regular uterine contractions. The data support the hypothesis that the uterine activity is regulated by the balance between PGF2 alpha and progesterone.

Female↗
PubMed1987

Adenosine triphosphate in human semen: a study on conditions for a bioluminescence assay.

A comparison of different procedures for adenosinetriphosphate (ATP) determination in whole ejaculates showed that it is advantageous to treat the specimens with trichloroacetic acid (TCA before quantification of ATP by bioluminescence). Semen samples from different men were found to cause varying degrees of inhibition of the luciferin-luciferase reaction. Hence, internal ATP standard had to be added to each sample to allow calculation of endogenous ATP. Mean recovery of ATP was 98.5%. The intrassay and interassay coefficients of variation were 3.0% and 3.9%, respectively. A correlation between the number of progressively motile spermatozoa and the ATP concentration was found (r = 0.89, P = 0.0005, n = 22). The mean level of ATP was 0.49 nmol/living sperm X 10(6) in semen with normal sperm motility and sperm density obtained from 22 men attending our fertility clinic. Seminal ATP was detected only in the spermatozoa.

Adenosine Triphosphate↗
PubMed1985

Entrainment of ventricular tachycardia by atrial depolarizations.

Four patients in whom rapid atrial pacing resulted in transient entrainment of a sustained ventricular tachycardia (VT) are reported. Ventricular fusion was seen in 3 of the 4. The following new observations were made: (1) A single atrial depolarization resulted in ventricular fusion and resetting of a VT, while atrial pacing at a faster rate entrained the same VT but without detectable fusion. This suggests that fusion during entrainment may be a rate-dependent phenomenon. (2) The interval between the last paced beat and the first nonpaced VT beat was different from the pacing cycle length in 3 patients. Two mechanisms accounted for this: the initial forces of each entrained QRS occurring as a result of the pacing wavefront, with fusion taking place only during the terminal forces, and the last entrained cycle exceeding the pacing cycle length by an amount related to the nonfused portion of the QRS, and delay in the presumed reentrant circuit responsible for the tachycardia. One VT was entrained with atrial pacing while ventricular pacing at the same rate resulted in termination, suggesting "site specificity" for termination. It is concluded that entrainment can occur without the criteria previously described as characteristic of it and that additional phenomena may be observed after stimulation that further support reentry as the mechanism of VT.

Adult↗
PubMed1985

The effect of naproxen on the concentration of prostaglandins in human seminal fluid.

Whole ejaculates were examined for their content of prostaglandins (PGs) during medication with 250 mg naproxen three times daily for 2 weeks. Six volunteers delivered semen samples before, periodically during, and after the period of medication. During treatment with naproxen, the concentration of PGE, PGF, 19-hydroxy-PGE, and 19-hydroxy-PGF significantly decreased. One week after cessation of medication the PG concentration had returned almost to that found before treatment. The four 19-hydroxy-PGF compounds could be determined separately and the relation between them estimated. The proportion of 8 alpha-19-hydroxy-PGF2 alpha increased, whereas that of 8 beta-19-hydroxy-PGF1 alpha decreased significantly during the medication period. No significant influence of the treatment on sperm density or motility could be observed. It is concluded that treatment with naproxen, a potent inhibitor of PG synthesis, significantly reduces the concentration of all PGs present in human seminal fluid. The implication of the effect on human fertility is discussed.

Alprostadil↗
PubMed1985

Comparative growth of SJL/J lymphomas in irradiated and normal SJL/J mice: cell cycle distribution and tumor cell quantification.

Flow cytometric and biological quantification of tumor cells revealed that 650 rad gamma-radiation 1 day prior to iv injection of H-2Ds negative lymphoma cells into SJL/J mice resulted in approximately a fourfold (day 3) to twelvefold (day 7) decrease in the tumor cell content of lymphoid organs as compared to that in unirradiated mice. Approximately 1.6-fold less tumor growth was noted (day 7) in 700-rad gamma-irradiated as compared to growth in unirradiated (SJL/J X CBA/J)F1 mice. Distributions of tumor cells in S-phase of the cell cycle were comparable at days 3, 5, and 7 in irradiated and unirradiated mice. Although approximately 26% of splenic tumor cells were in S-phase at days 5 and 7 in irradiated SJL/J mice, splenic tumor cell content did not increase during this time period. The data indicate that early (prior to day 3) and late (after day 5) events are responsible for decreased tumor growth in irradiated mice.

Animals↗
PubMed1984

The natural variations in prostaglandin concentration in human seminal fluid and its relation to sperm quality.

Prostaglandins E, F, 19-hydroxy E, and 19-hydroxy F (PGE, PGF, 19-OH-PGE, and 19-OH-PGF) in human semen were determined by a new chemical method. The method allows liquefaction to occur, a prerequisite for simultaneous estimation of PG concentration and sperm characteristics in the same ejaculate. The present study showed also that the variation in PG concentration between different individuals was more pronounced than in repeated ejaculates from the same individual. Sperm density and sperm motility seemed related to PG concentration. A high density was associated with a low PG concentration. The concentration of 19-OH-PGE was higher and that of 19-OH-PGF lower in ejaculates with a normal sperm motility than in those with an abnormal motility. It seems that functional requisites of sperm depend upon optimal seminal PG concentration.

Alprostadil↗
PubMed1982

Anaerobic bacteria in uterine infection following first trimester abortion.

Samples of uterine fluid and cervical mucus for bacterial culture were obtained from 23 patients with endometritis following first trimester abortion. Uterine samples were obtained via a sheathed system which minimizes contamination by the cervical flora. A mean of 3.4 isolates were identified in cervical samples as compared to 1.8 in uterine samples. Anaerobic bacteria were found in 57% of the uterine samples and dominated in both uterine and cervical samples. Peptostreptococcus species dominated in cervical samples and Bacteroides species in uterine samples. Significantly more bacterial species were found in uterine samples from patients with a high erythrocyte sedimentation rate. Since no bacteria were found in 39% of uterine samples a possible role of nonmicrobial pyrogenic substances is suggested.

Abortion, Induced↗
PubMed1980

Investigation of different combinations of estrogen therapy and radiation therapy on prostatic adenocarcinoma (R-3327).

The relative effectiveness of different combinations of estrogen therapy and radiation therapy against the R-3327 prostatic adenocarcinoma of the Copenhagen rat was studied. Because of similar actions of estrogens and radiation in the cell cycle, and possibly antagonistic effects reported in the clinical literature, we looked for an antagonism between these two therapeutic modalities. Radiation therapy consistently showed a greater tumor inhibitory effect than estrogen therapy alone at the dose tested. Combinations of radiation therapy with hormonal manipulation did not appear to show a greater inhibition of tumor growth than radiation therapy alone. There also did not appear to be an antagonistic effect between these two modalities in this system.

Adenocarcinoma↗
PubMed1979

Restricted replication of two alphaviruses in ricin-resistant mouse L cells with altered glycosyltransferase activities.

Two mouse L cell variant lines (CL 3 and CL 6) selected for resistance to the toxic plant lectin ricin were restricted in their ability to replicate the two alphaviruses Sindbis virus and Semliki Forest virus. CL 3 cells have been shown to exhibit increased CMP-sialic acid:glycoprotein sialyltransferase and GM3 synthetase activities, whereas CL 6 cells have been shown to contain decreased UDPgalactose:glycoprotein galactosyltransferase and UDP-N-acetylglucosamine:glycoprotein N-acetylglucosaminyltransferase activities. The adsorption of Sindbis virus to CL 6 cells was considerably reduced, suggesting that the loss or inaccessibility of the receptors for Sindbis virus accounted for a major defect in virus production in these cells. In contrast, CL 3 synthesized Sindbis viral RNA and proteins but were unable to convert the precursor glycoprotein PE2 to the structural protein E2. The cleavage of PE2 to E2 was also blocked in both CL 3 and CL 6 cells infected with Semliki Forest virus.

Galactosyltransferases↗
PubMed1977

Humoral immunostimulation. VII. Sialic acid masks antigenic sites on an antibody-selected bariant cell line.

Variant cell lines (LC1, LC2) obtained by growth of mouse L cells (L) in cytostimulatory and cytotoxic doses, respectively, of rabbit anti-L cell antiserum AL) were found previously to be altered in many ways relative to the parent cell line. A major change was the reduction of those surface membrane antigens that AL recognizes. These cell variants have now been found to have increased membrane sialic acid relative to L. Treatment of intact variant cells with neuraminidase (50 units/ml, 37 degrees C, 1 hr) greatly restored the susceptibility of LC1 to lysis with AL. In the presence of 1/100 dilution of AL and 5% complement the viability indices (1.00 = no cell kill) of untreated and neuraminidase-treated cells were respectively: L 0.10 and 0.03 and LC1 0.91 and 0.40. Neuraminidase-treated LC2 cells retained their resistance to AL. Parallel studies with 125I-ALIgG showed increased binding to neuraminidase-treated LC1 relative to native LC1. These findings suggest that the altered membrane sialic acid content affects the immunologic behavior of this cell variant by masking the original cell surface antibody-binding sites. This represents a possible mechanism for tumors to escape immunologic control.

Antibodies↗
PubMed1976

Isolation and characterization of two mouse L cell lines resistant to the toxic lectin ricin.

Two variant mouse L cell lines (termed CL 3 and CL 6) have been selected for resistant to ricin, a galactose-binding lectin with potent cytotoxic activity. The resistant lines exhibit a 50 to 70% decrease in ricin binding and a 300- to 500-fold increase in resistance to the toxic effects of ricin. Crude membrane preparations of CL 3 cells have increased sialic acid content (200% of control), while the galactose, mannose, and hexosamine content is within normal limits. Both the glycoproteins and glycolipids of CL 3 cells have increased sialic acid, with the GM3:lactosylceramide ratios for parent L and CL 3 cells being 0.29 and 1.5, respectively. In contrast, the membranes of CL 6 cells have a decrease in sialic acid, galactose, and hexosamine content with mannose being normal. Both cell lines have specific alterations in glycosyltransferase activities which can account for the observed membrane sugar changes. CL 3 cells have increased CMP-sialic acid:glycoprotein sialyltransferase and GM3 synthetase activities, while CL 6 cells have decrease UDP-GlcNAc:glycoproteinN-acetylglucosaminyltransferase and DPU-galactose:glycoprotein galactosyltransferase activities. The increased sialic acid content of CL 3 cells serves to mask ricin binding sites, since neuraminidase treatment of this cell line restores ricin binding to essentially normal levels. However, the fact that neuraminidase-treated CL 3 cells are still 45-fold resistant to ricin indicates that either a special class of productive ricin binding sites is not being exposed or that the cell line has a second mechanism for ricin resistance.

Carbohydrates↗
PubMed1975

Deficient uridine diphosphate-N-acetylglucosamine:glycoprotein N-acetylglucosaminyltransferase activity in a clone of Chinese hamster ovary cells with altered surface glycoproteins.

We have reported the isolation of a clone (termed 15B) of Chinese hamster ovary (CHO) cells which are deficient in certain plant lectin-binding sites and have decreased amounts of sialic acid, galactose, and N-acetylglucosamine in its membranes (Gottlieb et al. (1974) Proc. Natl. Acad. Sci. U.S.A. 71, 1078-1082). This study demonstrates that extracts of 15B cells, in contrast to the parent cell line, do not transfer N-acetylglucosamine residues from UDP-GlcNAc to certain glycopeptide and glycoprotein acceptors containing terminal nonreducing alpha-linked mannose residues. The decreased enzyme activity could not be accounted for by the presence of inhibitors, altered pH, or Mn2+ requirements of the glycosyltransferase or increased N-acetylglucosaminidase activity in the extracts. The finding that the 15B cell extracts have significant but reduced N-acetylglucosaminyltransferase activity toward a degraded orosomucoid acceptor suggests that these cells have a selective loss of one of several specific N-acetylglucosaminyltransferases which are present in the parent CHO cells. The sialyl- and galactosyltransferase activities of 15B and parent CHO cells are comparable. Parent CHO and 15B cells were grown in radioactive glucosamine to label the membrane glycoproteins. Solubilization of these glycoproteins and passage over a Ricinus communis agglutinin I (RCA I) Sepharose affinity column revealed that no labeled 15B glycoprotein material bound, whereas 50 percent of the CHO membrane glycoproteins bound and could be eluted with the haptene lactose, demonstrating that 15B cells are virtually devoid of membrane oligosacharides capable of binding to the RCA I lectin. The 15B membrane glycoproteins exhibited a marked shift toward glycoprotein species of lower molecular weight when examined by gel electrophoresis in sodium dodecyl sulfate. It is proposed that this shift in the mobility of the 15B membrane glycoproteins results from a decreased glycosylation of a number of membrane glycoproteins relative to their counterparts in CHO cells. The deficient N-acetylglucosaminyltransferase activity in 15B cells can account for the decreased glycosylation of the 15B cell membrane glycoproteins.

Cell Membrane↗
PubMed1975

Growth of enveloped RNA viruses in a line of chinese hamster ovary cells with deficient N-acetylglucosaminyltransferase activity.

Sindbis and vesicular stomatitis viruses were grown in a line (termed 15B) of Chinese hamster ovary (CHO) cells that is deficient in a specific UDP-N-acetyl-glucosamine:glycoprotein N-acetylglucosaminyltransferase. Both viruses replicated normally in the cell line, but the glycoproteins of the released virus migrated faster on sodium didecyl sulfate-polyacrylamide gels than did glycoproteins of virus grown in parent CHO cells. Digestion of the viral glycoproteins with Pronase followed by gel filtration demonstrated that the glycoproteins with Pronase followed by gel filtration demonstrated that the glycopeptides of Sinbis-15B virus were much smaller than the glycopeptides of Sindbis-CHO virus. In addition, Sindbis-15B viral glycopeptides but not Sindbis-CHO viral glycopeptides contained terminal alpha-mannose residues as shown by their susceptibility to alpha-mannosidase digestion. These findings demonstrate that the oligosaccharide units of the glycoproteins of vesicular stomatitis and Sinbis viruses are altered when the viruses are grown in 15B cells. We conclude that the N-acetylglucosaminyltransferase that is missing in 15B cells normally participates in the biosynthesis of the oligosaccharide units of the viral glycoproteins, and in the absence of this enzyme incomplete oligosaccharide chanis are produced. Viruses released from 15B cells appear to retain full infectivity; Sindbis-15B virus, however, showed a significant decrease in hemagglutination titer compared with that of Sindbis-CHO virus.

Animals↗
PubMed1974

Isolation of a clone of Chinese hamster ovary cells deficient in plant lectin-binding sites.

Ricin, a galactose-binding lectin with potent cytotoxic activity, was used to select a clone of Chinese hamster ovary cells with altered plant lectin-binding properties. The clone (15B) is 80-fold less sensitive to the toxic action of ricin than the parent line. In the absence of ricin, it grows both in monolayer and suspension culture with a normal generation time. Plating efficiency, however, is significantly reduced. Relative to the parent cells, its binding of the Ricinus communis lectins, Phaseolus vulgaris erythroagglutinating phytohemagglutinin, Abrus precatorius phytohemagglutinin, and soybean phytohemagglutinin is less than 7%, while binding of lentil phytohemagglutinin, wheat-germ agglutinin, and mushroom phytohemagglutinin is 17%, 40%, and 109%, respectively. In contrast, its concanavalin A binding is increased by 70%. Consistent with these alterations, crude membrane preparations of the 15B cells were found to contain the same sugars as the parent-cell membranes but in different proportions. The 15B membranes have 28% less sialic acid, 38% less N-acetylglucosamine, 49% less galactose, the same amount of N-acetylgalactosamine, and 53% more mannose than the membranes of the parent cells.

Animals↗
PubMedDate not supplied

Dynamic laser light scattering compared with video micrography for analysis of sperm velocity and sperm head rotation.

A new method which allows separation of the rotational and translational components of human sperm motility, based on the angular dependence of the dynamic laser light scattering (DLS) has been developed. The technique was used in a clinical study and was compared with an independent evaluation by video micrography. A good correlation was found between the two techniques when applied on different semen samples (r = 0.90; P less than 0.01 and r = 0.96; P less than 0.01 for rotation and translation, respectively) and when applied on the same semen sample at different temperatures. The rapid evaluation of these parameters using DLS technique opens the possibility to study large number of semen samples under physiological and pathological conditions at a lower cost.

Hot Temperature↗