Biomedical subjects

Shyam Thapa

Publications and source records attributed to Shyam Thapa.

8 recordsLinked to original sources

PubMed2025

Adrenomedullin overexpression protects mice from experimental bronchopulmonary dysplasia and associated pulmonary hypertension.

Bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PH) or BPD-PH is a lung disease of infants with significant morbidity. Adrenomedullin (Adm) is an angiogenic peptide that signals through calcitonin receptor-like receptor (Calcrl) and receptor activity modifying protein 2 (RAMP2). Adm deficiency potentiates hyperoxia-induced experimental BPD-PH in mice; however, whether Adm overexpression can mitigate this lung disease is unclear. Thus, we tested the hypothesis that Adm overexpression attenuates hyperoxia (HO)-induced murine experimental BPD-PH by using a novel transgenic mouse that overexpresses Adm globally (Admhi/hi mice). One-day-old Admhi/hi mice or their wild-type littermates (Adm+/+ mice) were exposed to HO ([Formula: see text] 70%) for 14 days and allowed to recover in normoxia (NO, [Formula: see text] 21%) for an additional 14 days. Controls were maintained in NO for 28 days. On postnatal day (P) 14, we harvested the lungs to determine the extent of Adm expression and apoptosis. On P28, we quantified alveolarization, lung vascularization, and PH. HO-exposed Adm+/+ mice demonstrated increased lung apoptosis, decreased alveolarization and lung vascularization, and indices of PH, indicating that neonatal HO exposure causes BPD-PH. However, Adm overexpression attenuated experimental BPD-PH, as evident by the decreased extent of hyperoxia-induced lung apoptosis and inflammation, alveolar and vascular simplification, pulmonary vascular remodeling, and PH in Admhi/hi mice than in Adm+/+ mice. Collectively, our results demonstrate that Adm overexpression attenuates HO-induced murine experimental BPD-PH, emphasizing the therapeutic potential of Adm for BPD-PH in preterm infants.NEW & NOTEWORTHY The deficiency of the proangiogenic peptide, adrenomedullin (Adm), exacerbates the severe infantile lung disorder, bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH), in mice. However, whether Adm therapy can mitigate this disease is unclear. Our study, conducted with a rigorous methodology, suggests a potential solution. Using a novel mouse that overexpresses Adm to overcome the pharmacological limitations of the peptide, we demonstrate that Adm can mitigate this disorder, highlighting the therapeutic potential of Adm for human BPD-PH.

Animals↗

PubMed2005

Early marriage and early motherhood in Nepal.

This paper examines age patterns of first marriage and motherhood and covariates of early marriage, delayed consummation of marriage and early motherhood in Nepal using data from the 2000 Nepal Adolescent and Young Adult Survey (NAYA). Both unmarried and married male and female youths (age 14-22) were included in the survey. The analysis is based on 2800 urban youths and 5075 rural youths with complete information on the variables examined. Proportional hazard models are used to estimate covariates of early marriage and early motherhood, and logistic regression models are used to estimate covariates of delayed consummation of marriage. The results show that early marriage and early motherhood are quite common among Nepalese women, especially in rural areas. Early marriage is much less common among men. Delayed consummation of marriage is common among very young brides, especially in rural areas. The main covariates associated with early marriage and early motherhood are respondent's education, region of residence and ethnicity. The main covariates of delayed consummation of marriage are age at first marriage, region of residence and ethnicity. The study highlights the need to focus on less educated female youths in the Terai region in order to reduce the reproductive and child health risks associated with early marriage and early childbearing.

Adolescent↗

PubMed2005

Effects of vitamin A supplementation on child mortality: evidence from Nepal's 2001 Demographic and Health Survey.

OBJECTIVE: To assess the effect of Nepal's vitamin A supplementation programme on child mortality at age 12-59 months. MATERIALS AND METHODS: Logistic regression, applied to retrospective data from Nepal's 2001 Demographic and Health Survey. RESULTS: After a number of potentially confounding variables are controlled, the effect of 100% community-level vitamin A coverage since the child's birth, relative to no coverage, is to reduce the odds of dying at age 12-59 months by slightly more than half (OR = 0.47, P = 0.03). CONCLUSIONS: The estimated beneficial effect of vitamin A supplementation on child mortality is larger than that found in most earlier clinical studies. This larger effect may be due mainly to the other health-related activities undertaken by the female community health volunteers who distribute vitamin A capsules.

Child Mortality↗

PubMed2005

Effect of iron supplementation during pregnancy on birthweight: evidence from Zimbabwe.

BACKGROUND: Iron deficiency in pregnant women has been shown to reduce the oxygen supply to the fetus, cause intrauterine growth retardation, and increase the risk of premature delivery and reduced birthweight. Yet the effects of iron supplementation programs on pregnancy outcomes are not well documented for developing countries. OBJECTIVE: To examine the relation between iron supplementation of mothers during pregnancy and children's birthweight using data from a national population-based survey in Zimbabwe. METHODS: The analysis uses information on 3559 births during the five years preceding the 1999 Zimbabwe Demographic and Health Survey. The effect of iron supplementation during pregnancy on birthweight was estimated by multiple regression, controlling for potential confounding effects of prenatal care, child's sex and birth order, mother's education and nutritional status (measured by body-mass index), household living standard, smoke exposure, and other variables. RESULTS: Babies born to mothers who received iron supplementation during pregnancy were 103 g heavier (95% confidence interval, 42-164; p = .001), on average, than babies born to mothers who did not receive iron supplementation during pregnancy. The difference was 64 g (95% confidence interval, 2-125; p = .043) for children whose birthweights were taken from health cards and 163 g (95% confidence interval, 44-281; p = .008) for children whose birthweights were reported by their mothers. CONCLUSIONS: Iron supplementation during pregnancy is associated with significantly higher birthweight, independent of other pregnancy care factors, mother's nutritional status, smoke exposure, and a number of demographic and socioeconomic factors. Prenatal iron supplementation programs can improve pregnancy outcomes and promote child survival in developing countries.

Adolescent↗

PubMed2004

Abortion law in Nepal: the road to reform.

In 2002 Nepal's parliament passed a liberal abortion law, after nearly three decades of reform efforts. This paper reviews the history of the movement for reform and the combination of factors that contributed to its success. These include sustained advocacy for reform; the dissemination of knowledge, information and evidence; adoption of the reform agenda by the public sector and its leadership in involving other stakeholders; the existence of work for safe motherhood as the context in which the initiative could gain support; an active women's rights movement and support from international and multilateral organisations; sustained involvement of local NGOs, civil society and professional organisations; the involvement of journalists and the media; the absence of significant opposition; courageous government officials and an enabling democratic political system. The overriding rationale for reforming the abortion law in Nepal has been to ensure safe motherhood and women's rights. The first government abortion services officially began in March 2004 at the Maternity Hospital in Kathmandu; services will be expanded gradually to other public and private hospitals and private clinics in the coming years.

Abortion, Induced↗

PubMed2004

Recent trends and components of change in fertility in Nepal.

The objectives of this article are, first, to provide improved estimates of recent fertility levels and trends in Nepal and, second, to analyse the components of fertility change. The analysis is based on data from Nepal's 1996 and 2001 Demographic and Health Surveys. Total fertility rates (TFR) are derived by the own-children method. They incorporate additional adjustments to compensate for displacement of births, and they are compared with estimates derived by the birth-history method. Fertility is estimated not only for the whole country but also by urban/rural residence and by woman's education. The own-children estimates for the whole country indicate that the TFR declined from 4.96 to 4.69 births per woman between the 3-year period preceding the 1996 survey and the 3-year period preceding the 2001 survey. About three-quarters of the decline stems from reductions in age-specific marital fertility rates and about one-quarter from changes in age-specific proportions currently married. Further decomposition of the decline in marital fertility, as measured by births per currently married woman during the 5-year period before each survey, indicates that almost half of the decline in marital fertility is accounted for by changes in population composition by ecological region, development region, urban/rural residence, education, age at first cohabitation with husband, time elapsed since first cohabitation, number of living children at the start of the 5-year period and media exposure. With these variables controlled, another one-third of the decline is accounted for by increase in the proportion sterilized at the start of the 5-year period before each survey.

Adolescent↗

PubMed2004

Triaging patients with post-abortion complications: a prospective study in Nepal.

The first manual vacuum aspiration (MVA) services unit in Nepal was established in 1995 at the country's largest national maternity hospital in Kathmandu. This research sought to assess and evaluate the safety, acceptability, and effectiveness of MVA services. This prospective study was conducted during 12 months in 1998, and follow-up was made at six weeks. Two groups of patients were compared: 529 patients treated in the MVA unit and 236 patients who were clinically eligible for treatment in the MVA unit but were treated instead in the main operation theatre (OT) owing to the unavailability of services in the MVA unit during the hours of their admission. The two groups differed with respect to some of their background characteristics but were similar in their clinical characteristics. The MVA group received contraceptive counselling and services and had significantly shorter stays in hospital. However, the direct cost incurred by the patients, regardless of the type of facility they used, was about the same. Follow-up at six weeks revealed that the MVA patients had significantly fewer complaints and were generally more satisfied with the services they had received than their counterparts. Slightly more than half of the women in the MVA group were using contraception at the time of follow-up compared to no women in the OT group. It is concluded that the MVA unit provided safe, effective, and efficient services to about 50% of all the patients admitted to the hospital with post-abortion complications. An additional 25% of the post-abortion patients could be served if the unit were kept open 24 hours a day, saving resources and time for patients and hospital staff. As a parallel development, both MVA and main OT services would need to be more effectively integrated with outside antenatal and family-planning clinics to address the reproductive health needs of women, thereby reducing the number of patients requiring post-abortion care.

Abortion, Induced↗

PubMed2003

Vasectomy effectiveness in Nepal: a retrospective study.

The main purpose of this retrospective, cross-sectional study was to evaluate the effectiveness of vasectomy in an ongoing public sector program in Nepal. We evaluated semen samples from men who had previously had a vasectomy, and asked about the occurrence of pregnancies in the men's partners. In addition, the surgeons who performed the vasectomies completed a questionnaire about their techniques. A two-stage stratified sampling procedure was used to select 1263 men from among over 30,000 men, who had previously undergone a no-scalpel vasectomy, mostly by ligation and excision, in 32 districts between July 1996 and June 1999. Semen samples were preserved and analyzed at a central laboratory. A US andrology laboratory validated the lab results. Twenty-three men (2.3%, 95% confidence interval [CI] 1.1-3.6) had >/=500,000 sperm/mL in their semen. Fifteen of those men reported pregnancies conceived after their vasectomy. In addition, six men with azoospermia reported pregnancies for which conception occurred within 3 months after vasectomy. Eleven men with azoospermia reported pregnancies for which conception occurred more than 3 months after vasectomy. Reported pregnancy was more likely in younger partners. The life table pregnancy rates for all men interviewed were 0.7 (95% CI 0.2-1.1), 1.7 (95% CI 1.4-2.1) and 4.2% (95% CI 3.2-5.2) at 3, 12 and 36 months, respectively. In low-resource, programmatic settings, vasectomy failure rates may be higher than commonly cited rates, especially in younger populations. Additional research is needed to determine if other occlusion techniques could reduce failure rates. Counseling on vasectomy should always convey the possibility of failure and partner pregnancy.

Adult↗