Biomedical subjects

C B Smikle

Publications and source records attributed to C B Smikle.

10 recordsLinked to original sources

PubMed1998

Elevated ovarian follicular fluid stem cell factor concentrations are associated with improved pregnancy rates in in-vitro fertilization cycles.

OBJECTIVE: To determine whether ovarian follicular fluid (FF) stem cell factor concentrations are associated with successful IVF pregnancies. DESIGN: Nested case-control design evaluation of stem cell factor levels from the FF of oocytes fertilized and transferred after controlled ovarian hyperstimulation. SETTING: University-based ART program. PATIENT(S): Infertile women undergoing IVF in a university-based ART program. INTERVENTION(S): Fifty-seven FF samples from a cohort of patients (n = 13) with tubal factor and unexplained infertility were stored at -80 degrees C and subsequently evaluated for stem cell factor concentration. Patients with endometriosis, polycystic ovary disease, and male factor infertility were excluded. Stem cell factor concentrations were measured using a commercially available ELISA kit according to the manufacturer's specifications. The groups were analyzed using a one-way analysis of variance, and significance was determined using the chi2 analysis of contingency table, the unpaired t-test, or the Mann-Whitney rank-sum test. MAIN OUTCOME MEASURE(S): FF stem cell factor concentration, pregnancy. RESULT(S): Stem cell factor concentrations were significantly higher in the FF of the patients who achieved successful pregnancies than in those who did not (641.7+/-75.2 pg/mL versus 475.5+/-50.58 pg/mL). CONCLUSION(S): Elevated FF stem cell factor concentrations are associated with an increased likelihood of IVF success. Therefore, stem cell factor may play a role in human follicular and oocyte development, and increasing infrafollicular stem cell factor concentrations may improve pregnancy rates after oocyte retrieval, fertilization, and ET.

Adult↗

PubMed1997

Hypo-osmotic swelling can accurately assess the viability of nonmotile sperm.

Viable, healthy sperm are preferred for oocyte fertilization with intracytoplasmic sperm injection. Currently, motility is the most widely applied measure of sperm viability. However, with this criterion, viable but immotile sperm are overlooked as candidates for micromanipulation. Supravital stains identify viable sperm but may be toxic to the gamete or embryo. We tested the hypothesis that hypo-osmotic swelling, developed to assess sperm membrane integrity, can accurately determine sperm viability. Thawed sperm from 12 fertile donors were exposed to a hypo-osmotic solution and to two supravital stains. A total of 2,010 sperm were assessed for tail coiling after a 30-min exposure to hypoosmotic solution. By supravital stains, 31% of thawed sperm were viable; 23% showed tail coiling. Among coiled-tail sperm, 100% were viable by supravital stain. As a measure of viability, tail coiling exhibited a sensitivity of 30%, specificity of 100%, and positive predictive value of 100% compared to supravital stains. With a 60-min hypo-osmotic incubation, the specificity (89%) and positive predictive value (78%) decreased significantly (P < 0.05). Therefore, hypo-osmotic swelling accurately detects viable sperm among a nonmotile population. Assay accuracy, however, is very sensitive to the incubation time in hypo-osmotic solution.

Benzimidazoles↗

PubMed1997

Effect of excessive GnRH-binding substance on circulating maternal hCG in human pregnancy.

Gonadotropin-releasing hormone (GnRH) can stimulate the release of placental human chorionic gonadotropin (hCG). Thus, at the onset of these studies it was the objective to define the relationship of hCG to GnRH in the maternal circulation throughout pregnancy, focusing on early pregnancy. Blood samples were collected at 8, 10, 12, 14, 16, 28 and 36 weeks of gestation during labor and the GnRH and hCG levels were determined by radioimmunoassay. Of 39 pregnancies, a GnRH-binding substance was found in the maternal circulation of three. This GnRH-binding substance resulted in erroneous GnRH levels, due to the very high non-specific binding. In the pregnant women without this GnRH-binding substance, GnRH attained highest concentrations at 12-14 weeks. The typical peak of hCG at 8-10 weeks of gestation was observed in this group, while the group of patients having the GnRH-binding substance had significantly lower hCG levels. Each of the patients with circulating GnRH-binding substance had prior pregnancy(s) and two of the three had a prior pregnancy loss. The nature of this GnRH-binding substance was investigated using gel chromatography. After incubation of [125I]GnRH with patient plasma for 3 days this substance was shown to be of high molecular weight which was ethanol precipitable. This binding substance may therefore be an antibody, since it appears to be a high molecular weight protein requiring a number of days to bind the [125I] GnRH. This GnRH-binding substance may be of physiological importance, since the circulating hCG level was significantly less in the group of patients with this substance than in those without.

Adolescent↗

PubMed1996

Circulating maternal corticotropin-releasing hormone and gonadotropin-releasing hormone in normal and abnormal pregnancies.

OBJECTIVE: Corticotropin-releasing hormone and gonadotropin-releasing hormone are produced by the human placenta and have been measured in the maternal circulation during pregnancy. Our objective was to determine concentrations of these substances in maternal plasma throughout normal pregnancies and in early pregnancy loss. STUDY DESIGN: Fifty-one pregnant women were followed up prospectively and plasma samples were drawn at 8, 10, 12, 14, 16, 28, and 36 weeks' gestation and during labor. Specific and sensitive radioimmunoassays were used to determine corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations in these samples. RESULTS: Blood samples were drawn at all time points and outcome data were available from 33 women who completed their pregnancies at term without complications. In this normal group circulating corticotropin-releasing hormone concentrations increased from low or undetectable concentrations at 8 weeks (< or = 23.2 +/- 1.3 pg/ml, mean +/- SEM) to measurable values at 16 weeks (34.3 +/- 2.2 pg/ml). Thereafter there was a significant increase to 1294 +/- 113 pg/ml in labor. Gonadotropin-releasing hormone demonstrated a trimodal distribution, increasing significantly from 8 to 14 weeks, decreasing at 16 weeks, and increasing again by term. The ratio of corticotropin-releasing hormone to gonadotropin-releasing hormone in the normal group demonstrated a 30-fold increase from 8 weeks to term. In eight cases of early pregnancy loss corticotropin-releasing hormone and gonadotropin-releasing hormone concentrations were not significantly different from those of the normal group in early pregnancy. In two cases of premature delivery gonadotropin-releasing hormone concentrations and ratios were within the normal range; corticotropin-releasing hormone levels were normal in both cases of premature delivery. CONCLUSION: In this study we determined maternal concentrations of corticotropin-releasing hormone and gonadotropin-releasing hormone in normal pregnancies and in labor at term. Neither maternal concentrations of corticotropin-releasing hormone nor gonadotropin-releasing hormone were useful in identifying pregnant women at risk for early pregnancy loss.

Abortion, Spontaneous↗

PubMed1996

Physical and sexual abuse in a middle-class obstetric population.

To evaluate the prevalence of a history of physical and sexual abuse in pregnant, economically stable, middle-class women with access to comprehensive health care, we issued self-report questionnaires to prenatal orientation classes at Wilford Hall Medical Center from October 19, 1992, to March 15, 1993. After identifying women who had been physically or sexually abused, we identified the assailant, the number of occurrences, and injuries resulting from the abuse. Of the 563 women who responded, 100 (18%) reported previous physical or sexual abuse. Seven women (1%) stated that they were physically abused during the pregnancy. Women were more likely to be physically than sexually abused by a spouse or lover (46% versus 13%). To identify women who have a history of abuse and to address their needs, practitioners should incorporate taking a history of physical and sexual abuse during the routine new obstetric visit.

Adult↗

PubMed1996

The impact of sexual abuse on job attrition in military recruits.

OBJECTIVE: To determine whether recruits entering the U.S. Air Force with a history of sexual abuse had a higher attrition rate from basic military training (BMT). METHODS: Retrospective, case-control study involving 28,918 recruits entering BMT from October 1, 1991, to September 30, 1992. Self-report questionnaires were given to all recruits on the second day of BMT. We compared recruits revealing a history of sexual abuse to all other recruits at the end of BMT and at the end of the next fiscal year. RESULTS: We found that victims of sexual abuse had a higher attrition rate from BMT than non-victims (10.6 versus 4.1%, p < 0.0001). Four and one-tenth percent of all recruits (1,289) reported a history of sexual abuse, and fewer male than female recruits reported a history of sexual abuse (1.5 versus 15.1%, p < 0.0001). However, after BMT there were no differences in any job performance indicators between victims and non-victims. CONCLUSION: We conclude that recruits with a history of sexual abuse had a higher attrition rate from BMT than those without a history of abuse; however, those recruits who did complete BMT were as successful as those who did not report a similar history of abuse.

Adult↗

PubMed1995

Physical and sexual abuse. A middle-class concern?

This study evaluated the prevalence of physical and/or sexual abuse in a population of employed, middle-class women who all have access to health care. Questionnaires were given to all patients who came to the ambulatory gynecology clinic at Wilford Hall Medical Center from October 19, 1992, to November 13, 1992. Questions were asked to ascertain the number of women who had experienced at least one episode of forced sexual contact or physical abuse. Other questions allowed identification of the relationship of the assailant to the respondent, number of occurrences and injuries resulting from the abuse. Of the 531 women who responded, 72 reported a history of only physical abuse, and 37 reported a history of only sexual abuse. Forty women reported that they were both physically and sexually abused. The typical victim of abuse was younger (32.6 vs. 39.8 years old, P < .001) and was more likely to work outside the home (63.1% vs. 47.9%, P < .005). Women were significantly more likely to be battered by a husband or lover than to be sexually assaulted by an intimate partner (75% vs. 16%, P < .001). Women who were both physically and sexually abused were injured more often than women who were only physically or sexually abused (60% vs. 28%, P < .01, and 60% vs. 24%, P < .01, respectively). Victims abused by an intimate partner were more likely to be abused on more than one occasion. All women should be asked about a recent history of abuse so that individuals identified can be counseled appropriately and attempts can be made to intervene to prevent further episodes of abuse.

Adult↗

PubMed1995

Measuring quantitative serum human chorionic gonadotropin. Variations in levels between kits.

Human chorionic gonadotropin (hCG) may be used in the monitoring of early pregnancy. It may also be used as a tumor marker in the diagnosis and follow-up of gestational trophoblastic disease, choriocarcinoma and testicular carcinoma. The combination of maternal serum unconjugated estriol, alpha-fetoprotein and quantitative hCG has shown promise as an antepartum screen for Down syndrome. In the quantitative assessment of hCG, the calibrators used by various kits are standardized to one of two different standards, either the Second International Standard or the First International Reference Preparation (IRP), established by the World Health Organization in 1968 and 1975, respectively. The IRP is now considered the Third International Standard, and both terms may be used interchangeably. Confusion may exist in clinical situations if quantitative hCG levels determined by assays in different laboratories using different standards are compared or used simultaneously. Practitioners are advised to be aware of which calibration standard is utilized in their laboratory and to interpret the results accordingly.

Chorionic Gonadotropin↗

PubMed1995

Clinical predictors in the evaluation of a pelvic mass.

OBJECTIVE: To determine the frequency by age of ovarian malignancies in women with a pelvic mass and to assess preoperative indicators for ovarian cancer. METHODS: Inpatient charts from June 1, 1990, to August 30, 1992, were reviewed with preoperative diagnoses of a pelvic mass. Preoperative evaluation, surgical procedure, and pathologic diagnoses were recorded. Comparisons were made using the Fisher exact test. RESULTS: In patients with ovarian disease, benign masses were found more commonly than malignancies (72 versus 13%, respectively). Ovarian malignancies were more common in patients over age 50 than in patients younger than 50 (25.6 versus 5.1%; p < 0.001). Preoperative platelet count, CA 125, and ultrasound findings did not identify patients with ovarian malignancy. CONCLUSIONS: Ovarian malignancies are uncommon in young women, but the risk of malignancy increases with age. Elevated CA 125 levels may prove to be helpful in evaluating pelvic masses in postmenopausal women.

Adult↗

PubMed1995

Surgical correction of severe vaginal introital stenosis in female baboons (Papio sp.) infected with simian agent 8.

Simian agent 8 (SA8) is a neurotropic, endemic alphaherpesvirus in Papio sp. Lesions associated with simian agent 8 infections usually involve the genitalia of sexually mature baboons. In females, secondary bacterial infections may lead to scarring of the vulva and perineum, with resulting vaginal obstruction. Affected baboons are poor breeders and often develop urinary tract infections due to retention of urine in the vagina. Reconstructive vaginal surgery was performed on seven baboons with vaginal obstruction. Four weeks before surgery, 50 mg of Depo-Provera was administered intramuscularly to each animal to arrest the estrous cycle, reduce swelling, and allow adequate surgical exposure of the vagina. Ventral and circular incisions were made around the constricted vagina. The peripheral skin was excised to break down the underlying connective tissue, allowing access to the vaginal mucosa. Healthy vaginal tissue was then opposed to the incised skin edges with 3-0 Vicryl in an interrupted pattern. Once healed, the vaginas remained patent, allowing normal mating and urination. Nine months after surgery, five baboons had healthy infants, and pregnancy was confirmed in the other two animals. The described procedure may allow female baboons previously infertile and at risk of urinary tract infections to be returned to a healthy reproductive state.

Animals↗