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Biomedical subjects

J A Collins

Publications and source records attributed to J A Collins.

At least 73 records · Page 4Linked to original sources
PubMed1990

Treatment-dependent and treatment-independent pregnancy among women with periadnexal adhesions.

In an attempt to evaluate the efficacy of salpingoovariolysis we studied 147 women who were found to have periadnexal adhesions on laparoscopic examination. Among these women, 69 were treated by laparotomy and salpingoovariolysis and 78 were not treated. There was no significant difference between the degree of adhesions in the treated group and in the nontreated group. With the use of life table analysis, the cumulative pregnancy rate at 12 and 24 months follow-up was 32% and 45% in the treated group and 11% and 16% in the nontreated group, respectively (p less than 10(-6)). We suggest that although pregnancy might occur in infertile women who have periadnexal adhesions, treatment with salpingoovariolysis is associated with a higher pregnancy rate.

Adnexal Diseases↗
PubMed1990

The value of semen analysis and sperm function assays in predicting pregnancy among infertile couples.

Over a 2-year period, 227 couples were evaluated by an extended assessment of the male partner's ejaculate. This extended assessment comprised sperm penetration of denuded hamster oocytes, ability of sperm to penetrate synthetic mucus, and the adenosine triphosphate (ATP) content of whole semen. In proportional hazards analysis adjusting for the contribution of clinical and other seminal variables, the sperm penetration assay (SPA) test was a predictor of pregnancy in the subgroup with normal conventional seminal variables (greater than 40 million motile sperm per ejaculate). When the SPA result was 20% or more the probability of pregnancy was 3.7 times higher; the performance of the SPA as a diagnostic test was better in the couples with treated tubal disease than in other diagnostic categories.

Acrylamides↗
PubMed1989

Unexplained infertility: evaluation of treatment with clomiphene citrate and human chorionic gonadotropin.

A double-blind, randomized, prospective therapeutic trial was conducted in 148 couples with unexplained infertility. Treatment consisted of 4 consecutive months of placebo or clomiphene citrate (CC) (100 mg) by mouth on cycle days 5 to 9, and placebo or human chorionic gonadotropin (hCG) (5,000 IU) intramuscularly on cycle days 19, 22, 25, and 28. There were 14 pregnancies during the trial and 39 pregnancies during observation before and after the trial. Placebo treatment resulted in no pregnancies over 4 months. Clomiphene citrate was significantly better than placebo (P less than 0.04), with a pregnancy rate of 19% over the course of 4 months. The pregnancy rate with hCG either alone (11%) or in combination with CC (7.6%), was not significantly better than placebo. Treatment-independent pregnancies, defined as those before treatment (but after enrollment), or more than 1 month after therapy, occurred in 16% of the couples, with a mean time to conception of 8.8 months. As part of their follow-up, 39 of the study couples subsequently underwent in vitro fertilization (IVF), and 43% were found to have a previously unrecognized male factor or fertilization defect. A pregnancy rate of 16% was achieved after a mean of 1.1 cycles in these 39 couples. The authors conclude that CC is useful in treating unexplained infertility and is a reasonable initial therapy. For couples who fail to conceive, IVF may be diagnostic as well as therapeutic.

Adult↗
PubMed1989

Age of the female partner is a prognostic factor in prolonged unexplained infertility: a multicenter study.

Among 2,106 couples registered in 12 Canadian infertility clinics, 470 (22.3%) were classed as unexplained infertility after a uniform evaluation of the male ejaculate, ovulation, and tubal patency. The unexplained group included more older female partners; 44% were over 30 years of age at registration in the participating clinics, compared with 36% in other infertility diagnostic groups. The mean duration of infertility was 40.1 months, and the cumulative pregnancy rate was 36.6 +/- 2.9% at 2 years after registration. When the variables were examined with the use of proportional hazards analysis, each additional month of duration of infertility reduced the expected prognosis by 2%, and a history of pregnancy in the partnership improved the prognosis by 80%. Among couples with 3 years or more duration of infertility (cumulative pregnancy rate, 27.5 +/- 3.9%), an additional year in the age of the female partner when conception was first attempted (mean, 26.8 years) reduces the prognosis by 9%.

Adult↗
PubMed1989

Metastatic malignant struma ovarii presenting as paraparesis from a spinal metastasis.

A 42-yr-old woman had a solitary metastases to her spine (T2) from a malignant struma ovarii. The thyroid was excluded as the site of the primary cancer. The lesion caused paraparesis. The spinal metastasis was treated by surgery and two doses of 131I (200 mCi each time). The patient responded very well and is entirely free of symptoms and signs. Repeat whole-body 131I scan shows no abnormality.

Adult↗
PubMed1988

Evaluation of technetium pertechnetate as a radionuclide marker of pulmonary aspiration of gastric contents in rabbits.

At present, there is no sensitive and specific test to confirm the clinical impression that a respiratory disorder is due to aspiration of gastric contents. Since intravenous technetium pertechnetate (99mTcO4-) has been shown to be safe, actively concentrated in the gastrointestinal tract, and secreted into gastric juice, we sought to determine whether 99mTcO4-, when given intravenously, is suitable to detect pulmonary aspiration of small amounts of gastric contents in rabbits. Biodistribution studies over 24 h revealed that 99mTcO4- persistently appeared in the stomach, thyroid, and salivary glands and did not appear in the lungs. Pharmacokinetic studies showed that 99mTcO4- was rapidly picked up by the stomach wall and secreted promptly into the stomach lumen and that the stomach wall persistently secreted 99mTcO4- into stomach contents for 24 h. By injecting 99mTcO4- through an intratracheal catheter in order to simulate aspiration, the radioactive threshold for imaging intrapulmonary 99mTcO4- was determined to range between less than 0.5 microCi and 2 microCi, depending on the amount of background activity in the blood pool. By measuring the radioactivity in stomach contents (microCi/g), over 24 h after intravenous injection of 2 mCi of 99mTcO4-, we were able to calculate the amount of aspirated stomach contents that our technique should reveal at various time points. We concluded from this preliminary feasibility study that 99mTcO4-, when given intravenously, is suitable to detect pulmonary aspiration of small amounts (less than or equal to 4 ml for 8 h after an intravenous dose of 2 mCi) of gastric contents in human patients. Since our biodistribution studies show that saliva as well as stomach contents are potential sources for any aspirated 99mTcO4-, how to distinguish aspiration of oropharyngeal from stomach contents remains to be determined. It also remains to be determined how long 99mTcO4- remains in the lungs after it has been instilled; clearance that is too rapid significantly decreases the ability of this agent to reveal aspiration.

Animals↗
PubMed1987

Interpretation of semen analysis among infertile couples.

Among the male partners of 1074 infertile couples the mean results of semen analysis were sperm count 78 X 10(6)/ml, seminal volume 4.0 ml, proportion of progressively motile sperm 54%, proportion of sperm with normal morphologic features 81.4% and total motile sperm count 152.3 X 10(6) per ejaculate. After excluding 65 couples who chose donor insemination and 300 with known female causes of infertility, the cumulative pregnancy rates in the remaining 709 couples were higher with increasing sperm density and motility and seminal volume, but the higher rates were significant only when these variables were combined into total motile sperm count per ejaculate. The cumulative pregnancy rates were 20% with a total motile sperm count of 9 X 10(6) or less, 37% with a count of 10 to 19 X 10(6) and 52% with a count of 20 X 10(6) or more (p = 0.001). Counts higher than 20 X 10(6) were not associated with a further improvement in pregnancy rates, but variability in the results was high, which suggests that the test should be repeated as necessary to determine the true range. Although standards for these and other seminal variables are ill defined, the total motile sperm count incorporates the most useful prognostic information from semen analysis, and the associated pregnancy rates can help guide clinical decisions.

Female↗
PubMed1987

Receiver-operating characteristics curves for semen analysis variables: methods for evaluating diagnostic tests of male gamete function.

This study draws on decision analysis to estimate the utility of seminal variables in predicting pregnancy. The infertile couples selected (n = 709) excluded those who had donor insemination or known female factors (history of pelvic infection, ovulatory disorders, endometriosis, and tubal disease). Diagnostic test properties were calculated with respect to pregnancy for two variables derived from the semen analysis report: sperm density, and the total number of motile sperm in the ejaculate (TMS). Receiver-operating characteristic (ROC) curves based on sensitivity and specificity revealed that none of the proposed thresholds for sperm density or TMS is clearly a best choice. The highest positive predictive values for sperm density (75%) and TMS (75%) were associated with cutoff points at five million sperm per milliliter and five million motile sperm per ejaculate, respectively. The false positive rates when these cutoff points were used were 4.3% (sperm density) and 5.6% (TMS). ROC analysis provides visual and numeric evidence of the quality of a diagnostic test and constitutes a set of procedures for incorporating information from new tests of male gamete function into the diagnostic assessment of infertility.

Clinical Laboratory Techniques↗
PubMed1986

The better prognosis in secondary infertility is associated with a higher proportion of ovulation disorders.

To determine the reason for the higher pregnancy rate in couples with secondary infertility, the authors compared 237 infertile couples who had a previous pregnancy in the current partnership (secondary infertility) with 135 infertile couples in whom the woman had been pregnant only in a previous partnership and 925 couples with primary infertility. Couples with secondary infertility had the highest proportion of ovulation disorders (36%); these couples with secondary infertility and an ovulation disorder had the shortest duration of infertility (26 months). Cumulative pregnancy rates at 36 months were 56% in secondary fertility, 44% in primary infertility, and 42% in pregnancy in a previous partnership (P = 0.001). In this study, the better prognosis in secondary infertility may be related to the higher proportion of couples with ovulation disorders, who had a shorter duration of infertility. Abortion rates in the earlier pregnancies with current or previous partners were 37% and 30%, respectively; after the period of infertility, the abortion rates were 14% and 12%, respectively.

Abortion, Spontaneous↗
PubMed1986

The effects of prostaglandin E1 on the adult respiratory distress syndrome in septic primates.

The effects of prostaglandin E1 (PGE1) on the adult respiratory distress syndrome were studied in the septic primate (Macaca fascicularis). A 30-min infusion of Escherichia coli (1 X 10(10)/kg) resulted in severe septic shock and adult respiratory distress syndrome. Primates, if living, were killed 4 h after completion of the E. coli infusion. Three groups of primates were studied (n = 4 in each group). The control group (Group 1) received PGE1 at 100 ng/kg/min throughout the experiment. The septic group (Group 2) received a 30-min infusion of E. coli. The treatment group (Group 3) received a continuous PGE1 infusion (100 ng/kg/min) along with the E. coli infusion which was begun 30 min after the PGE1 infusion was started. Control primates had hemodynamic changes consistent with the vasodilatory effect of PGE1 (heart rate and cardiac output increased; blood pressure and systemic vascular resistance (SVR) decreased). All control animals survived the experiment and had no evidence of pulmonary damage. Primates given E. coli developed severe hypotension, decreased SVR, and lung injury evidenced by pulmonary edema, decreased oxygenation, and increased extravascular lung water. Primates treated with both PGE1 and E. coli developed similar cardiovascular and pulmonary changes as the septic group. There was no statistically significant difference between Group 2 and Group 3 animals with regard to mean arterial blood pressure, SVR, extravascular lung water, alveolar-arterial oxygen difference, or survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Alprostadil↗
PubMed1986

Effects of anti-C5a antibodies on the adult respiratory distress syndrome in septic primates.

In vitro and in vivo studies have suggested that human complement component C5a plays a key role in neutrophil injury in the adult respiratory distress syndrome (ARDS). First, using leukocyte aggregometry, we demonstrated that the addition of a recently developed rabbit anti-human polyclonal antibody to C5a des arg to endotoxin-activated plasma prevented leukocyte aggregation in vitro. We then administered the anti-C5a des arg antibody to septic primates (Macaca fascicularis). Three groups of primates, control, septic, and anti-C5a antibody treated septic, were studied (n = 4 in each group). A 30-min infusion of Escherichia coli (1 X 10(10)/kg) resulted in severe sepsis and ARDS. Primates were killed 4 h after completion of the E. coli infusion. Septic animals not treated with anti-C5a antibody had 75% mortality (3/4), decreased oxygenation, severe pulmonary edema, and profound hypotension. Septic primates treated with anti-C5a antibodies did not die and did not develop decreased oxygenation (P less than 0.05) or increased extravascular lung water (P less than 0.05). They also had a marked recovery in their mean arterial blood pressure (P less than 0.05). This study demonstrates that treatment with rabbit anti-human C5a des arg antibodies attenuates ARDS and some of the systemic manifestations of sepsis in nonhuman primates.

Animals↗