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T L Anderson

Publications and source records attributed to T L Anderson.

At least 37 records · Page 2Linked to original sources
PubMed1990

Immunohistochemical localization of epidermal growth factor receptor during implantation in the rabbit.

Epidermal growth factor receptor was localized immunohistochemically during implantation (gestational days 7 through 14) in the rabbit. During early implantation (days 7 through 9), immunostaining was observed in the cytoplasm and on the surface of the syncytiotrophoblastic knobs. By day 8, immunoreactivity was most pronounced in knobs interacting directly with uterine epithelium but was noted in nonknob cytotrophoblast as well. Fetal membranes, identified by day 10, were stained intensely on all days examined. In later gestation the trophoblast was stained intensely on the surface and in the cytoplasm, with some staining over nuclei. No appreciable changes in the staining pattern were observed after day 10. Uterine epithelium demonstrated epidermal growth factor receptor staining first on the antimesometrial (day 7) and then the paraplacental epidermal (day 9). After day 10, most staining was at the embryo-maternal interphase. These data suggest that the embryo and uterine epithelia can receive signals from their environment during and after implantation through the epidermal growth factor receptor.

Animals↗
PubMed1990

Epithelial cells from normal human endometrium express a tumor-associated glycoprotein (TAG-72) epitope in vitro.

Monoclonal antibody B72.3 identifies a tumor-associated glycoprotein (TAG-72) epitope derived from a human breast carcinoma metastasis. Recently, expression of this epitope was noted in normal endometrium during the secretory, but not proliferative, menstrual interval. In light of known hormonal control of normal endometrial growth and differentiation, we investigated in vitro expression of TAG-72 epitope in purified endometrial epithelium cultured under serum-free conditions on Matrigel biomatrix. Cells from secretory endometrium exhibited homogeneous tumor-associated glycoprotein 72 epitope expression. Unexpectedly, epithelium from the proliferative interval developed expression after 5 to 6 days of culture. Epithelial cells from both intervals maintained expression over 12 days of culture without exogenous estradiol and progesterone. Spontaneous, uniform expression of tumor-associated glycoprotein 72 epitope by normal endometrial epithelial cells in vitro is in marked contrast to the cyclic, heterogeneous expression observed in vivo. Such expression also differs from published in vitro observations of cancer cell lines that express this epitope.

Antibodies, Monoclonal↗
PubMed1990

Facioscapulohumeral muscular dystrophy: evidence for selective, genetic electrophysiologic cardiac involvement.

Facioscapulohumeral muscular dystrophy is an autosomal dominant disorder with an incidence of 3 to 10 cases per million. The only type of cardiac involvement ascribed to this neuromuscular disorder is a unique form of heart disease--permanent atrial paralysis. However, reported cases of facioscapulohumeral muscular dystrophy probably represented instead what is now recognized as phenotypically similar Emery-Dreifuss dystrophy. Cardiac involvement, therefore, has not been convincingly reported in facioscapulohumeral muscular dystrophy, but because of the clinical similarity of that disorder to Emery-Dreifuss dystrophy and its genetic variants, a prospective investigation of the electrophysiologic properties of the atria and atrioventricular (AV) node and infranodal conduction was undertaken in 30 rigorously documented cases of facioscapulohumeral muscular dystrophy. All patients had a 12 lead surface electrocardiogram (ECG), 22 had a 24 h ambulatory ECG, 15 patients had two-dimensional echocardiographic/Doppler studies and 10 patients underwent 12 intracardiac electrophysiologic investigations. Left atrial, right atrial or biatrial P wave abnormalities were present in 60% of the surface ECGs. Evidence of abnormal AV node or infranodal conduction was present on intracardiac electrophysiologic study or surface ECG in 27% of patients. Atrial flutter or fibrillation was induced by single atrial extra stimuli in 10 of the 12 intracardiac electrophysiologic studies. Sinus node function was abnormal in three patients. This investigation provides the first secure evidence of cardiac involvement in facioscapulohumeral muscular dystrophy. The involvement is represented by relatively high susceptibility to induced atrial flutter or fibrillation during electrophysiologic study, together with less frequent evidence of abnormal sinus node function and abnormal AV node or infranodal conduction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Progesterone antagonist (RU 486) for cervical dilation, labor induction, and delivery in monkeys: effectiveness in combination with oxytocin.

A progesterone antagonist (RU 486), combined with oxytocin, was effective in achieving cervical dilation, labor induction, and early delivery in near-term monkeys. Effects of RU 486 included accelerated flow of colostrum and transiently enhanced weight gain in infants. No overt toxicity on fetuses, mothers, or newborns was detected with the use of a single oral dose of 25 mg.

Animals↗
PubMed1989

Noncompetitive antiestrogenic effect of RU 486 in blocking the estrogen-stimulated luteinizing hormone surge and the proliferative action of estradiol on endometrium in castrate monkeys.

The noncompetitive antiestrogenic effects of RU 486 were examined using estradiol (E2)-treated ovariectomized monkeys given RU 486, progesterone (P), or both. The E2-induced luteinizing-hormone (LH) surge of control animals was abrogated by P and/or RU 486. Secretory transformation by P was inhibited by RU 486 coadministration. RU 486 alone (1 mg/kg) induced endometrial secretory transformation, but higher doses (5 mg/kg) inhibited proliferation and secretory activity. Thus in the presence of P, RU 486 is antagonistic but, in absence of P, exhibits endometrial progestational effects at low doses and an antiproliferative (antiestrogenic) effect at higher doses. These data encourage continued evaluation of RU 486 as a potential contraceptive agent acting at the pituitary and/or endometrial level.

Animals↗
PubMed1989

Adverse effects of methylene blue on human sperm motility, components of human reproductive tract fluids, and mouse embryo cleavage.

Because methylene blue exhibits germicidal, oxidation, and reduction properties, the authors asked whether this agent causes adverse effects on gametes, embryos, and/or secretions of the reproductive tract. Time- and dose-dependent inhibition of human sperm motility by methylene blue was observed, as was growth inhibition of 2-cell mouse embryos. Furthermore, the presence of methylene blue in uterine, fallopian tube, and peritoneal fluids altered protein mobility in polyacrylamide gels, and yielded apparent values of follicle-stimulating hormone and estradiol up to 260% of actual values (P less than 0.05). These data suggest that the presence of methylene blue in reproductive tract fluids may provide a false impression of their biochemical and biophysical compositions, and that the use of methylene blue as a chromopertubation agent be conducted with appropriate awareness.

Adult↗
PubMed1989

Hormonal manipulation of endometrial maturation.

Three experimental protocols were devised to induce endometrial maturation in 12 women with ovarian failure. Each was planned to serve a dual purpose: to resolve a particular clinical situation related to synchronization between ovum donor and recipient and to answer a specific question about endometrial physiology. A fourth protocol of sequential estrace (2-6 mg/day) and progesterone (P4; 25-50 mg/day, im) simulating the 28-day natural cycle, served as a control protocol (18 cycles). A short follicular phase protocol consisted of only 6 days of estrogen (E) administration before addition of P4 (13 cycles). In the long follicular phase protocol (5 cycles), estrace was given for 3-5 weeks, and P4 administration was accordingly postponed. In 6 accelerated secretory transformation cycles, 150 mg/day P4 were administered, im, from day 15 onward. The adequacy of the induced endometrial cycles was evaluated by hormonal, morphological, and histochemical criteria relevant to endometrial normalcy and receptivity. Serum estradiol levels and the areas under the estradiol curves for the long and short follicular phase protocols differed significantly from those during the control cycles (P less than 0.005). Areas under the estradiol curves in the accelerated secretory transformation protocol yielded significantly higher P4 values than those in all other protocols (P less than 0.05). All biopsies in the 3 experimental protocols compared favorably with those of the control protocol. Glycocalyx intensity (periodic acid-Schiff) and the amount of galactose residues in the glycocalyx (Ricinus communis-I agglutinin) were greatest during the periimplantation interval. We conclude that a very short exposure of the human endometrium to E or, conversely, prolonged E stimulation will allow normal endometrial maturation with the addition of P4. Supraphysiological doses of P4 in the accelerated secretory transformation protocol significantly enhanced endometrial maturational processes.

Adult↗
PubMed1989

Mouse monoclonal antibodies against human sperm: evidence for immunodominant glycosylated antigenic sites.

Thirty mouse monoclonal antibodies (MoAbs) raised against human sperm detect common antigenic determinants on human lymphocytes, erythrocytes, bacteria and endotoxin. Specific chemical, enzymatic and lectin blocking studies indicate that the sperm-associated antigens defined by these MoAbs are glycoconjugates. Further studies including reactivity of these MoAbs with organic sperm extracts indicate that the predominant carriers of these carbohydrate antigens are glycolipids and that the terminal immunodominant monosaccharide may be N-acetyl-glucosamine or N-acetylgalactosamine.

Animals↗
PubMed1989

The acute effect of cordocentesis with or without fetal curarization and of intravascular transfusion upon umbilical artery waveform indices.

The systolic/end-diastolic ratio (S/D) and pulsatility and resistance indices were calculated before and after diagnostic cordocentesis in 46 fetuses, after 19 intravascular transfusions in eight fetuses, and on two occasions 45 minutes apart in eight controls. The fetus was paralyzed with pancuronium (0.3 mg/kg sonographic estimate of fetal weight) for diagnostic cordocentesis on 19 occasions (intravascularly in 17 and intramuscularly [IM] in two). Pancuronium (intravascularly in 16; IM in three) and furosemide (4 mg/kg intravenously) were administered during each transfusion. There were no significant differences between the first and second measurements for any of the three indices in the control group. Significant reductions were documented in the S/D ratio (P less than .0001), the pulsatility index (P = .043), and the resistance index (P less than .0001) after diagnostic cordocentesis. Pancuronium administration did not alter the magnitude of the decline, nor was there an association between the decline and the volume of blood removed. Significant relationships were observed between the magnitude of the decline and several respiratory blood gas measurements. As in the diagnostic cordocentesis group, there were significant reductions in each Doppler index after transfusion (S/D ratio, P = .003; pulsatility index, P = .002; resistance index, P = .0001). In addition, there was a significant relationship between gestational age and S/D ratio (r = 0.70, P = .002) in fetuses undergoing intravascular transfusion. The S/D ratio was most sensitive to changes in fetal oxygenation. We conclude that both diagnostic cordocentesis and intravascular transfusion as performed at the University of Iowa acutely lower the studied Doppler waveform indices.

Blood Flow Velocity↗
PubMed1988

Transplacental passage of a progesterone antagonist in monkeys.

The progesterone antagonist RU 486 dramatically increases myometrial contractility of the pregnant uterus, making it a potential adjunctive therapy for labor induction or therapeutic pregnancy termination. Sixteen female cynomolgus monkeys were studied during the second or third trimester of pregnancy. Hysterotomies were performed with the animals under anesthesia, providing access to the intact placental vasculature. RU 486 (25 mg) was injected intravenously into the mothers. Serial blood samples were drawn from the maternal and fetal-placental compartments for a period of 2 hours. RU 486 achieved a gradient equilibrium between the maternal and fetal-placental circulation within 5 minutes, suggesting free passage by simple diffusion. The clearance kinetics of immunoreactive RU 486 are consistent with an open three-compartment system in mother and fetus. The fetal-placental index decreased from 31.2% to 17.8% between the second and the third trimester of pregnancy. There was no acute toxicity of the RU 486 noticed during the experimental course.

Animals↗
PubMed1987

Identification of gonadotropin surge-inhibiting factor (GnSIF) in follicular fluid and its differentiation from inhibin.

Exposure of rat pituitary cell cultures to charcoal-extracted porcine follicular fluid (pFF) inhibits gonadotropin-releasing hormone (GnRH) stimulation of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release in a dose-dependent manner. The inhibition of GnRH-stimulated gonadotropin secretion (gonadotropin surge-inhibiting factor [GnSIF] activity) by pituitary cells in vitro requires up to 24-48 h preexposure to pFF. One microliter of pFF inhibits approximately 50% of the GnRH-stimulated LH release and is defined as 1 unit of GnSIF activity. Basal LH secretion is unaltered under these conditions. GnSIF activity is distinct from that of inhibin, which selectively suppresses basal release of FSH but not LH. A partially purified preparation of inhibin contains less than 1% as much GnSIF activity as inhibin activity. GnSIF activity is resistant to moderate heat treatment (60 degrees C for 60 min) and is fully recovered after acetone precipitation. Chromatography of pFF on heparin/Sepharose affinity matrix effectively separates inhibin from GnSIF. Whereas inhibin has a high affinity for heparin, GnSIF activity does not associate with this affinity matrix and is recovered in the column void volume. In summary, we have developed an in vitro bioassay for the detection of GnSIF activity in pFF. Moreover GnSIF activity seemingly derives from a molecular entity distinct from inhibin, having different physicochemical characteristics and differential effects on pituitary gonadotropin secretion.

Animals↗
PubMed1987

Trends in teenage pregnancy. A comparison of Douglas County, Nebraska, and national statistics.

Teenage pregnancy is a significant health and economic problem in the United States. However, both national and Nebraska statistics show that teenage fertility rates and the percentage of teen births vs. total births are decreasing. The national rate decreased from 19% in 1975 to 13.7% in 1984. The Nebraska rate paralleled the national rate, decreasing from 13% in 1977 to 9.7% in 1984. The Douglas County, Nebraska, rate also decreased, from 21.8% in 1978 to 17.5% in 1985. These trends have been noted for both black and white teens and are statistically significant. The percentage of abortions and births to unmarried teens vs. nonteens has also decreased both nationally and statewide.

Abortion, Induced↗
PubMed1986

Stage-specific alterations in the apical membrane glycoproteins of endometrial epithelial cells related to implantation in rabbits.

The rabbit endometrial epithelium undergoes differentiation prior to the time of blastocyst implantation, including loss of surface negativity and a change in glycocalyx morphology. Nonpregnant (estrous) and pseudopregnant rabbits were used to study specific alterations in proteins and saccharide composition of the luminal epithelial membrane and its glycocalyx related to the acquisition of receptivity to implantation. Pregnant animals were used to study further modification of the luminal surface by implanting blastocysts. The apical surface of luminal epithelial cells was solubilized by a 15-min intraluminal incubation of 1% Triton X-100 containing protease inhibitors. Proteins in extract solutions were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Three new polypeptides (24 kDa, 42 kDa and 58 kDa) were identified in uteri from receptive rabbits. Binding of succinyl Wheat Germ Agglutinin (sWGA) and Ricinus communis Agglutinin (RCA-I) lectins to the 24 kDa and 42 kDa components on Western blots of extracts separated by SDS-PAGE identified them as glycoproteins. Additionally, other polypeptides (26 kDa, 80-86 kDa and 145 kDa) showed changes in affinity for WGA, RCA-I or concanavalin A (Con A), depending on the hormonal state. Correlating with these findings was an increased binding of these lectins to intact nonciliated cells in uteri of receptive rabbits compared to estrous animals; ciliated cells bound Dolichos biflorus Agglutinin (DBA) specifically, regardless of the hormonal condition. Treatment of uteri from estrous animals, or Western blots of proteins from these animals, with neuraminidase prior to lectin exposure suggested the presence of glycoproteins having a sialic acid-D-galactose terminus in nonreceptive rabbits. Reduced binding of lectin to intact cells at implantation sites and to blots of proteins isolated from these sites, compared to nonimplantation sites, was noted. These results provide evidence for stage-specific alterations in protein and saccharide composition of the apical surface of endometrial epithelium prior to implantation, and indicate that implanting blastocysts further modify the luminal surface.

Animals↗
PubMed1986

Monoclonal antibodies recognize a cell surface marker of epithelial differentiation in the rabbit reproductive tract.

Monoclonal antibodies against the cell surface were produced by immunizing mice with endometrial scrapings prepared from 6-day pregnant rabbits. Spleen cells from an immune mouse were fused with myeloma cells and cultured by standard hybridoma technology methods. Hybridoma supernatants were screened for reaction with the apical epithelial surface by immunohistochemistry on frozen sections of uterus from 6-day pregnant rabbits, and positive colonies were cloned by limiting dilution. Ascites fluid was produced in mice from hybridoma clones that gave a consistent pattern of apical epithelial surface staining through 6 sub-clonings. Antibodies in the ascites fluid were tested by immunohistochemistry on frozen sections of uterus, oviduct, lung, liver and kidney from nonpregnant or 6-day pregnant rabbits. At a dilution of 1:5000, the antibodies recognized an antigen that was specific to the apical surface of luminal but not glandular epithelium of the 6-day pregnant uterus and could not be detected in the nonpregnant uterine epithelium. At higher concentrations of antibody (1:100 to 1:1000), crossreaction was seen with antigens in stromal and myometrial cells of pregnant and nonpregnant uterus. At a dilution of 1:5000, the antibody also crossreacted with some components of lung, liver and kidney but without discriminating between the two reproductive states. In the oviduct, staining of the surface epithelium was specific to the pregnant state. We conclude that this monoclonal antibody has a high affinity for a luminal epithelial cell surface antigen in the reproductive tract of the pregnant rabbit and shows multiple organ reactivity with other tissues that is not affected by pregnancy. This antigen will provide a useful cell surface marker of epithelial differentiation in the progestational reproductive tract.

Animals↗
PubMed1985

The glycocalyx of the mouse uterine luminal epithelium during estrus, early pregnancy, the peri-implantation period, and delayed implantation. I. Acquisition of Ricinus communis I binding sites during pregnancy.

Mouse uteri were examined during estrus, early pregnancy, the peri-implantation period, and delayed implantation to determine whether changes in the surface coat of the luminal epithelium could be associated with receptivity of the uterus to the presence of blastocyst-stage embryos or blastocyst adhesion. By using alkaline bismuth subnitrate to label periodate-oxidized glycols within the glycocalyx we were able to measure the thickness and examine the morphology of the glycocalyx by electron microscopy. Ferritin-conjugated Ricinus communis agglutinin (RCA-I) demonstrated the presence of D-galactose at terminal, nonreducing positions within the glycocalyx. A relatively thick (0.06-0.1-micron) surface coat was present during estrus, but contained almost no RCA-I binding sites. During Day 3 of pregnancy the surface coat remained up to 0.1 micron thick and RCA-I binding sites were present. At Day 4 and during delay the glycocalyx had a fibrillar appearance, contained RCA-I binding sites, and was reduced to 0.06-0.08 micron in thickness. During Day 5 of pregnancy the thickness of the surface coat was greatly reduced, but there remained uniform lectin binding adjacent to the plasma membrane both at sites of blastocyst attachment and between implantation sites. The results indicate that the luminal epithelium of the mouse uterus acquired RCA-I binding sites during pregnancy and that the thickness of the surface coat was greatly reduced at the time of implantation.

Animals↗