Biomedical subjects

Michael J Zinaman

Publications and source records attributed to Michael J Zinaman.

4 recordsLinked to original sources

PubMed2006

Using cervical mucus and other easily observed biomarkers to identify ovulation in prospective pregnancy trials.

To help fulfil the objectives of prospective studies of pregnancy and human development, such as the National Children's Study, there is a need to pinpoint ovulation and conception in a cohort of women. This paper discusses the suitability of using natural and easily observed markers of ovulation for detection of the most likely day of ovulation and conception. Of the biomarkers supported by clinical data, the use of cervical mucus is emphasised as it appears most promising. A considerable amount of data suggests that observation of changes in vaginal discharge from cervical mucus can closely approximate the day of ovulation, is easy to learn and suitable for a large group of women. While this approach could also be cost-effective, a significant drawback may be the learning phase which may take 2-3 instructional sessions for women to fully identify recurring changes across the menstrual cycle.

Biomarkers↗

PubMed2004

Relationship between soft tissue body composition and bone mass in perimenopausal women.

OBJECTIVES: Perimenopause, the transition into menopause, marks the beginning of accelerated bone loss, contributing to the development of osteoporosis, a major public health problem. This perimenopausal transition has also been associated with a decrease in body lean mass, an increase in fat mass, and an increase in body weight. How these changes in fat mass and lean mass may influence bone mineral density (BMD) is currently unknown. The purpose of this study is to determine the independent effect and relative contribution of lean mass and fat mass to BMD in perimenopausal women. MATERIAL AND METHODS: The sample consisted of 43 sedentary perimenopausal women (age: mean = 49.6; S.D. = 3.2) with an intact uterus and ovaries, participating in a study of exercise and perimenopausal symptoms. Total body BMD, regional BMD, and soft tissue body composition were measured by dual-energy X-ray absorptiometry. Other measures including age, height, weight, and serum FSH and E2 were also obtained. RESULTS: Findings revealed that 14% of these perimenopausal women had low bone mass (osteopenia) in the lumbar spine and/or the femoral neck. Overall body fat mass and lean mass had positive relationships with BMD of lumber spine and the femur. However, using multiple regression analyses, only lean mass and ethnicity remained significant predictors for BMD of the femoral neck (r2 = 45%) with lean mass explaining more variance than ethnicity. Lean mass was the sole predictor of total proximal femur BMD explaining 38% of the variance. Fat mass was not a significant predictor of BMD at any skeleton site. CONCLUSIONS: These findings suggest that body lean mass, not fat mass, is a significant contributor to femoral BMD in perimenopausal women.

Absorptiometry, Photon↗

PubMed2003

Relationship between sperm characteristics and hormonal parameters in normal couples.

OBJECTIVE: To examine the relationships between hormone profiles and semen analysis measures and fertility in the male partners of presumed normal couples. DESIGN: Prospective clinical study. SETTINGS: Healthy volunteers in an academic research environment. PATIENT(S): One hundred forty-five reproductive age couples without known risk factors for infertility and who had discontinued contraception to achieve pregnancy completed this component of this study. Each couple was followed for < or =12 menstrual cycles while they attempted to conceive. INTERVENTION(S): Semen quality measures for the first ejaculates were obtained at the start of the study along with a single blood sample. Levels of FSH, bioactive FSH, inhibin B, LH, and T were measured for each man. MAIN OUTCOME MEASURE(S): Semen analysis, FSH, inhibin B, LH, T, and clinical pregnancy. RESULTS: Significant positive relationships were observed between the two measures of FSH as well as between both of the FSH measures and LH. Follicle-stimulating hormone as measured by RIA was significantly negatively correlated with inhibin B. Inhibin B showed a marginally significant negative correlation with LH, and LH and T had a marginally significant positive correlation. Inhibin B increased significantly, and both measures of FSH activity showed significant decreases, with increasing levels in several semen quality measures. There was no significant relationship between the measured hormones and the pregnant and nonpregnant groups or time to pregnancy. CONCLUSION(S): These results contribute additional information on the utility of reproductive hormone measurements for predicting semen quality in couples without known reduced fertility.

Adult↗

PubMed2003

Laparoscopic appendectomy in an outpatient setting.

STUDY OBJECTIVE: To determine the ability to perform laparoscopic appendectomy on an outpatient basis. DESIGN: Prospective study (Canadian Task Force classification II-2). SETTING: University ambulatory surgery center. PATIENTS: Forty-two consecutive patients. INTERVENTION: Laparoscopic appendectomy. MEASUREMENTS AND MAIN RESULTS: After performing five laparoscopic appendectomies, three women required hospitalization. Thus a new multimodal protocol was implemented and admission and recovery times were monitored. After the new protocol was implemented, only 1 of 37 patients required hospitalization. Discharge times were similar to those for women undergoing gynecologic laparoscopy without appendectomy. CONCLUSION: With attention to surgical and anesthetic protocols, appendectomy can be performed at the time of gynecologic laparoscopy in an ambulatory setting without a significant delay in discharge.

Adolescent↗