The impact of climate on the prevalence of respiratory tract infections in early childhood in Lahore, Pakistan.

BACKGROUND: Respiratory tract infections are a major health problem in developing countries. The aim of this study was to analyse the impact of the climate on the prevalence of upper respiratory tract infection (URTI) and lower respiratory tract infection (LRTI) in four socioeconomically different groups in a developing country. METHODS: A prospective cohort study was conducted among children in four socioeconomically different groups in Lahore, Pakistan. Monthly observations were made on 1476 infants born during 1984-1987 and followed for 24 months. Prevalence of URTI and LRTI was analysed according to age, area of living, family size, time of birth, the season of the year and climate variables such as rain, temperature and humidity. RESULTS: Low monthly average minimum day temperature was associated with high prevalence of URTI and LRTI. For LRTI the impact of temperature was larger for boys, children living in larger families and children living in the poorer areas. This pattern was not seen for URTI. A peak in prevalence for LRTI was shown at 5-6 months of age for LRTI and at 10-12 months of age for URTI. CONCLUSIONS: Temperature is related to prevalence of URTI and LRTI in a developing society. The effect of temperature on health varies between different subgroups. These effects should be considered in planning health actions to prevent respiratory tract infections.     

Early-life risk factors for adult chronic disease: follow-up of a cohort born during 1964-1978 in an urban slum of Lahore, Pakistan

Evidence suggests that risk of chronic diseases may be programmed during the foetal and early life of the infant. With high rates of low birthweight coupled with a rapid nutritional transition, low-income countries are facing an epidemic of chronic diseases. Follow-up of a cohort of adults born during 1964-1978 in an urban slum in Lahore, Pakistan, is presented in this paper. In 695 of these adults (mean age=29.0 years, males=56%), blood pressure, fasting blood glucose, and body mass index (BMI) were measured to assess early-life predictors of risk of chronic diseases. Sixteen percent of the study population was born with a low birthweight (<2,500 g). A significant positive association (p=0.007) was observed between birthweight and BMI; additionally, adjusting for age and gender, the association with BMI was highly significant (p=0.000). Conversely, a significant negative association (p=0.016) was observed between birthweight and adult levels of fasting plasma glucose; after adjustment for age and gender, the association was more significant (p=0.005) No association was observed between birthweight and adult blood pressure. The results suggest that low birthweight may increase later risk of impaired glucose tolerance in urban Pakistani adults. Further research in this area is warranted.     

Biocompatibility of silica coated NaYF(4) upconversion fluorescent nanocrystals

Here we report the synthesis of uniform silica coated hexagonal-phase NaYF(4) nanocrystals with strong NIR-to-visible upconversion fluorescence and its cytotoxicity and biodistribution in a rat model. The silica coated NaYF(4) nanocrystals were incubated with rat skeletal myoblasts and bone marrow-derived mesenchymal stem cells and cytotoxicity was assessed by using MTS and LDH assay. Healthy rats were injected intravenously with the nanocrystals so as to further investigate their biocompatibility and tissue distribution. The results from this study revealed that the silica coated NaYF(4) upconversion nanocrystals displayed good in vitro and in vivo biocompatibility, demonstrating their potential applications in both cellular and animal imaging systems.     

Vasopressin: behavioral roles of an "original" neuropeptide

Vasopressin (Avp) is mainly synthesized in the magnocellular cells of the hypothalamic supraoptic (SON) and paraventricular nuclei (PVN) whose axons project to the posterior pituitary. Avp is then released into the blood stream upon appropriate stimulation (e.g., hemorrhage or dehydration) to act at the kidneys and blood vessels. The brain also contains several populations of smaller, parvocellular neurons whose projections remain within the brain. These populations are located within the PVN, bed nucleus of the stria terminalis (BNST), medial amygdala (MeA) and suprachiasmatic nucleus (SCN). Since the 1950s, research examining the roles of Avp in the brain and periphery has intensified. The development of specific agonists and antagonists for Avp receptors has allowed for a better elucidation of its contributions to physiology and behavior. Anatomical, pharmacological and transgenic, including "knockout," animal studies have implicated Avp in the regulation of various social behaviors across species. Avp plays a prominent role in the regulation of aggression, generally of facilitating or promoting it. Affiliation and certain aspects of pair-bonding are also influenced by Avp. Memory, one of the first brain functions of Avp that was investigated, has been implicated especially strongly in social recognition. The roles of Avp in stress, anxiety, and depressive states are areas of active exploration. In this review, we concentrate on the scientific progress that has been made in understanding the role of Avp in regulating these and other behaviors across species. We also discuss the implications for human behavior.     

Snake bite in Chittagong Division, Bangladesh: a study of bitten patients who developed no signs of systemic envenoming

The demographics, epidemiology, first aid, clinical management, treatment and outcome of snake bites causing no significant signs of systemic envenoming were documented in Chittagong Medical College Hospital, Bangladesh, between May 1999 and October 2002. Among 884 patients admitted, 350 were systemically envenomed and 534 were without signs of either systemic or significant local envenoming. The average age of patients with physical evidence of snake bite but no systemic envenoming was 26.4 years. Most had been bitten on their feet or hands. Ligatures had been applied proximal to the bite site in >95% of cases and the bite site had been incised in 13%. Patients were typically discharged at 24 h. Those with clinical signs of systemic envenoming resembled the non-envenomed cases demographically and epidemiologically except that they arrived at hospital significantly later than non-envenomed patients, having spent longer with traditional healers. No non-envenomed patient was treated with antivenom and none went on to develop symptoms of systemic envenoming after discharge. The potential complications and confusing signs caused by ligatures and incision demand that all patients admitted with a history of snake bite be kept under observation for 24 h after admission even if they have no signs of systemic envenoming.     

Patterns of metastasis and survival in breast cancer patients: a preliminary study in an Iranian population

Due to lack of sufficient data on characteristics of breast cancer patients and risk factors for developing metastasis in Iran this study was designed to understand clinical aspects impacting on survival. A cross-sectional study on breast cancer patients was conducted in an oncology clinic of the university hospital between 1995 and 2010. Data were retrieved from medical records and included age, menopausal status, tumor diameter, number of involved nodes, histopathological type, estrogen and progesterone receptor expression, c-erbB-2, primary and secondary metastasis sites, overall survival, disease free interval and type of chemotherapy protocol. The results were analyzed with SPSS 13 software.The mean age of the patients was 49.2 (27-89) years. The primary tumors were mainly ER positive (48%) and PR negative (49.3%). The status of lymph nodes dissected and examined in these patients was unknown in 19 patients (25.3%) while 18 patients (24%) had positive lymph nodes with no report on the number of involved nodes. All of the patients had received antracyclin based chemotherapy in an adjuvant or metastatic setting. Adjuvant hormonal therapy was administered to receptor positive patients. In average, overall survival after recurrence was 30 months (95%CI 24.605-35.325) for non-skeletal versus 42 months (95%CI 31.211-52.789) for skeletal metastasis (P= 0.002). The median survival was also greater for receptor positive patients; 39 months (95%CI 33.716-44.284) for PR+ versus 26 months (95%CI 19.210-32.790) for PR- (P=0.047) and 38 months (95%CI 32.908-43.092) for ER+ versus 27 months (95%CI 18.780-35.220) for ER- patients (P=0.016). No relation was found between site of first metastasis and hormone receptor, age, tumor diameter, DFI and menopausal status. Sites of metastasis were independent of age, size of the tumor, menopausal and hormone receptor status in this study. Overall survival provided significant relations with respect to receptor status and bone metastasis.