Association of seasonal reproductive patterns with changing food availability in an equatorial carnivore, the spotted hyaena (Crocuta crocuta).
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Reproductive seasonality was examined in an equatorial population of free-living spotted hyaenas (Crocuta crocuta) in Kenya. The study population was observed continuously for 10 years, during which time the dates of all births, conceptions, weanings, and cub deaths were recorded. Local prey abundance was estimated two to four times per month, and rainfall was recorded daily throughout the study period. Births occurred during every month of the year, but a distinct trough in births occurred from February to May. This trough occurred approximately one gestation period after the phase of the annual cycle during which prey animals were least abundant in the home range of the hyaenas, and conceptions occurred most frequently when food abundance was greatest. Neither rainfall nor cub mortality were correlated with births or conceptions. Thus, although spotted hyaenas are capable of breeding throughout the year, they exhibit a moderate degree of seasonality that most likely reflects responses to seasonal variation in energy availability. (+info)
Preconception counseling and women's compliance with folic acid supplementation.
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QUESTION: I am counseling patients to take folic acid when they plan pregnancy and during early pregnancy. Is there any proof that counseling really causes women to comply? ANSWER: A recent Motherisk study showed that counseling women who were planning pregnancy about folic acid use is very effective: 71% of those counseled took folic acid, compared with only 17% of those who were not counseled. (+info)
Correlation between disparity for the minor histocompatibility antigen HA-1 and the development of acute graft-versus-host disease after allogeneic marrow transplantation.
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Results of a previous study suggested that recipient mismatching for the minor histocompatibility antigen HA-1 is associated with acute graft-versus-host disease (GVHD) after allogeneic marrow transplantation. In that study, most patients received either cyclosporine or methotrexate for GVHD prophylaxis, and a cytotoxic T-cell clone was used to test for HA-1 disparity. To facilitate large-scale testing, we developed a method that uses genomic DNA to identify HA-1 alleles. A retrospective study was conducted to correlate HA-1 disparity and the occurrence of acute GVHD in 237 HLA-A2-positive white patients who had received a marrow or peripheral blood stem cell transplant from an HLA-identical sibling. All patients received both methotrexate and cyclosporine for GVHD prophylaxis. The presence of HLA-A*0201 was confirmed in 34 of the 36 HA-1 disparate pairs by sequencing the HLA-A locus. Grades II-IV GVHD occurred in 22 (64.7%) of these 34 patients, compared with 86 (42.8%) of the 201 patients without HA-1 disparity (odds ratio, 2. 45; 95% confidence interval [CI], 1.15 to 5.23; P =.02). Recipient HA-1 disparity showed a trend for association with acute GVHD (odds ratio, 2.1; 95% CI, 0.91 to 4.68; P =.08) when a multivariable logistic regression model was used to include additional risk factors. These data are consistent with results of the previous study, suggesting an association between HA-1 disparity and risk of acute GVHD, but the strength of this association may be lower in patients who received both methotrexate and cyclosporine than in those who received methotrexate or cyclosporine alone. (+info)
Urinary incontinence: an unexpected large problem among young females. Results from a population-based study.
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BACKGROUND: The International Continence Society has defined urinary incontinence as a condition in which involuntary loss of urine is objectively demonstrable and is a social or hygiene problem. Urinary incontinence is presumably a common health problem among women even in younger ages. OBJECTIVES: The primary aim was to investigate the prevalence of urinary incontinence (UI) in a female population with a special focus on younger women (18-30 years old). The secondary aim was to investigate the association between UI and number of deliveries, use of contraceptives or oestrogen substitutions, and urinary tract infections (UTIs). METHODS: A population-based study with a self-administered questionnaire was set in the community of Surahammar, Sweden. Subjects were all women (3493) aged 18-70 years living in Surahammar during 1995. The main outcome measures were the prevalence of UI and variables such as number of deliveries, use of contraceptives or oestrogen substitutions, and UTIs. RESULTS: Twenty-six per cent of the women reported problems of UI. The prevalence of UI in younger women was 12%. The number of reported complaints of UTIs was significantly higher in the women with UI compared with women without urinary incontinence (wUI). In the younger women UTI, nulliparous or having given birth to one or two children were most frequent in those with UI. The use of contraceptives was more common in younger women without UI (P < 0.05). However, the use of oestrogen was more common in older women in the age group 51-70 years with UI (P < 0.01). CONCLUSION: Our findings have shown that 26% of the women who took part in the survey reported problems of UI. Among women below 30 years of age, 12% reported complaints of UI. We found a high prevalence of UI in younger women with a UTI, not taking oestrogen, nulliparous or having given birth to one or two children. There are needs for further investigations with a special focus on younger women. (+info)
Transitory expression of the A2b adenosine receptor during implantation chamber development.
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Adenosine is a short-range signal molecule that surges in the mouse uterus immediately after blastocyst implantation (Blackburn et al. [1992] Dev. Dyn. 194:155-168). The present study has investigated patterns of uterine adenosine receptor expression during early post-implantation development. Strong expression of the A2b adenosine receptor was observed. Utilizing northern blot analysis, in situ hybridization, and immunostaining, the source of expression was mapped to the primary and secondary decidua of the antimesometrial region, between days 4-8 of gestation. Distribution of the A2b receptor protein followed that of the corresponding transcript by about one gestational day and reflected the dynamics of antimesometrial tissue organization during implantation chamber development. Uterine adenosine surges to levels sufficient for A2b receptor engagement during a defined period (i.e., days 4-6) after blastocyst implantation. Decidual A2b receptor expression thus defines a transitory window of murine gestation that corresponds to a period of human gestation encompassing most spontaneous pregnancy losses. Because adenosine receptors are sensitive to metabolically stable adenosine analogues, their differential expression during implantation chamber development may hold therapeutic potential in the prevention of early pregnancy loss. Dev Dyn 1999;216:127-136. (+info)
Risk factors for coronary heart disease in African American women.
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There have been few studies of risk factors for coronary heart disease in African American women. The authors investigated factors associated with prevalent coronary heart disease in data provided by participants in the Black Women's Health Study. In 1995, 64,530 US Black women aged 21-69 years completed postal health questionnaires. The 352 women who reported having had a heart attack (cases) were frequency matched 5:1 on age with 1,760 women who had not (controls); medical record review for 35 cases indicated that two-thirds had had a heart attack and the remainder had other coronary heart disease. Odds ratios, obtained from multiple logistic regression analyses, were significantly elevated for cigarette smoking, drug-treated hypertension, drug-treated diabetes mellitus, elevated cholesterol level, and history of heart attack in a parent. High body mass index (kg/m2) was associated with coronary heart disease in the absence of control for hypertension, diabetes mellitus, and elevated cholesterol but not when they were controlled, suggesting that obesity may influence risk as a result of its effects on blood pressure, glucose tolerance, and cholesterol levels. Odds ratios increased with increasing parity and with decreasing age at first birth. These data suggest that important risk factors for coronary heart disease are similar in Black women and White women. (+info)
Sex ratios, family size, and birth order.
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In many countries, the male:female ratio at birth has varied significantly over the past century, but the reasons for these changes have been unclear. The authors observed a close parallel between decreasing family size and declining male:female sex ratio in Denmark from 1960 to 1994. To explain this finding, they examined the sex ratio and birth order of 1,403,021 children born to 700,030 couples. Overall, 51.2% of the first births were male. However, families with boys were significantly more likely than expected to have another boy (biologic heterogeneity). By the fourth birth to families with three prior boys, 52.4% were male. The increase varied directly with the number of prior boys (p for trend = 0.0007). Furthermore, couples with boys were more likely to continue to have children. In summary, the authors found that the declining male:female ratio in Denmark and probably other European populations is mainly attributable to three effects: declining family size, biologic heterogeneity, and child sex preference. Why families with boys are more likely to have additional boys is unknown. (+info)
Donor age is paramount to success in oocyte donation.
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Several reports suggest increasing age in oocyte donors decreases the chances of in-vitro fertilization (IVF) success, while others describe no effect. The published data concerning gravidity and parity are similarly conflicting. To further address these questions, we retrospectively studied 445 consecutive donor IVF cycles at two large university-based IVF practices. Donor cycles were analysed for the number of oocytes retrieved, gravidity, parity, and age of the donor, and pregnancy outcome in recipients. The previous gravidity and parity of the donor were not associated with successful pregnancy in recipients. The number of oocytes retrieved was positively correlated with pregnancy. However, after adjusting for donor age, neither prior fertility nor the number of oocytes retrieved were significant predictors. In contrast, the donor's age was highly associated with recipient success. We conclude that the age of the oocyte donor is a significant predictor of pregnancy success and should be a major factor in selecting prospective candidates. The gravidity and parity of the donor are insignificant predictors, as are the total number of oocytes retrieved at the time of oocyte harvest. (+info)