RESUMEN

Global oceanic regions are rapidly changing in terms of their temperature, oxygen, heat content, salinity and biogeochemistry. Since the biogeochemistry of the oceans is important and pivotal for global food production, and a major part of the world population relies on marine resources for their daily life and livelihood, it is imperative to monitor and find the spatio-temporal changes in the primary productivity of oceans. Here, we estimate the changes in Chlorophyll-a (Chl-a) and Net Primary Productivity (NPP) in the north Indian Ocean (NIO) basins of Bay of Bengal and Arabian Sea for the period 1998-2019. We find a substantial reduction of NPP in NIO since 1998 (-0.048 mg m-3 day-1 yr-1) and the increase in sea surface temperature (SST) (+0.02 °C yr-1) is the primary driver of this change. Furthermore, there is a significant (10-20%) change in the air mass or dust transport to NIO from the period Decade 1 (1998-2008) to Decade 2 (2009-2019). This change in air mass trajectories has also altered NPP in both basins through the changes in nutrient input and associated biogeochemistry. Henceforth, this study cautions the changes in primary productivity of NIO, and suggests regular assessments and continuous monitoring of the physical and biological processes from a perspective of food security and ecosystem dynamics.

RESUMEN

Anthropogenic emissions have produced significant amount of carbon dioxide (CO2) in the atmosphere since the beginning of the industrial revolution. High levels of atmospheric CO2 increases global temperature as CO2 absorbs outgoing longwave radiation and re-emits. Though a well-mixed greenhouse gas, CO2 concentration is not uniform in the atmosphere across different altitudes and latitudes. Here, we uncover a region of high CO2 concentration (i.e. CO2 pool) in the middle troposphere (500-300 hPa) over the Indo-Pacific Warm Pool (IPWP, 40° E-140° W, 25° S-25° N), in which the CO2 concentration is higher than that of other regions in the same latitude band (20° N-20° S), by using CO2 satellite measurements for the period 2002-2017. This CO2 pool extends from the western Pacific to the eastern Indian Ocean. Much of the CO2 pool is over the western Pacific Ocean (74.87%), and the remaining lies over the eastern Indian Ocean (25.13%). The rising branch of Walker circulation acts as a "CO2 Chimney" that constantly transports CO2 released from the natural, human-induced and ocean outgassing processes to the middle and upper troposphere. The CO2 pool evolves throughout the year with an average annual trend of about 2.17 ppm yr-1, as estimated for the period 2003-2016. Our analysis further reveals that La Niña (El Niño) events strengthen (weaken) the CO2 pool in the mid-troposphere. The radiative forcing for the CO2 pool suggests more warming in the region and is a grave concern for global warming and climate change.

RESUMEN

Hypertension is recognized as a key risk factor for cardiovascular disease mortality and morbidity. Early detection of prehypertensive stage may help an individual to lead a healthy life by altering the life style. The present study was attempted to compare blood pressure response and anthropometric parameter in children of hypertensive and non hypertensive parents. The study was conducted on total 120 participants, 60 in control and 60 in test group. Cardiovascular response to stress was determined by Harvard step test. Heart rate (HR) and blood pressure response to exercise were measured in supine position before exercise and at 1, 2, 3, 4, 5, 7 and 10 minutes after the exercise. The results were expressed as Mean±SD and analyzed using Independent t- test (unpaired t-test) for comparison between the control group and the test group and one way ANOVA test. The "P" value < 0.05 was considered statistically significant. In the present study, body mass index (BMI), waist hip ratio (WHR) and waist circumference (WC) were found to be significantly higher in normotensive individuals with family history of hypertension. Stress induced changes in systolic blood pressure SBP), diastolic blood pressure (DBP), heart rate (HR) were found to be significantly higher in normotensive individuals with family history of hypertension as compared to normotensive individuals without family history of hypertension. The increased blood pressure and heart rate observed in the individual of hypertensive parents emphasizes the importance of genetic influence on hypertension. This blood pressure elevation may be considered as a permanent abnormality characterizing a prehypertensive stage early in life.

Asunto(s)

RESUMEN

BACKGROUND: Atherosclerosis is a multi-factorial disease involving the interplay of genetic and environmental factors. Studies highlighting the public health importance of risk factors like chronic infections causing acute myocardial infarction (AMI) in the Indian context are scarce. This study was undertaken to study the association of socio-demographic and life-style factors with acute myocardial infarction in central India. MATERIALS AND METHODS: The cases and controls were group-matched for age, gender, and socio-economic status. A blinded research associate administered the study questionnaire. We performed an unconditional multiple logistic regression analysis. RESULTS: The case-control study included 265 cases of AMI and 265 controls. The results of final model of logistic regression analysis for risk factors of AMI included 11 risk factors at α = 0.05. They were waist hip ratio, body mass index, stress at home in last 1 year, hypertension, family history of CHD, past history of gingival sepsis, tobacco smoking, raised total serum cholesterol, Chlamydia pneumoniae, Helicobacter pylori and raised C-reactive protein. CONCLUSION: The findings confirm the role of conventional risk factors for cardiac disease and highlight need for research into the association between chronic infections with AMI.

RESUMEN

BACKGROUND: Coronary heart disease is multi-factorial in origin and its burden is expected to rise in developing countries, including India. Evidence suggests that the inflammation caused by infection is associated with the development of atherosclerosis and heart disease. An increasing number of clinical and experimental studies point to a contribution of various infectious organisms to the development of atherosclerosis in humans. Acute myocardial infarction (AMI) is associated with atherosclerosis. OBJECTIVES: The objective of the following study is to study the association between Helicobacter pylori, Chlamydia pneumoniae and C-reactive protein (CRP) with AMI. MATERIALS AND METHODS: This group-matched case-control study was carried out in Government Medical College, Nagpur, Maharashtra, India. The study compared the risk of occurrence of AMI (outcome) if subjects were ever-infected with H. pylori or C. pneumoniae; and their CRP positivity (exposure). Incident cases of myocardial infarctions in a tertiary care hospital were included as cases. RESULTS: The study recruited 265 cases and 265 controls and detected an odds ratio (OR) of 2.50 (95% confidence interval [CI]: 1.69-3.70) and an OR of 2.50 (95% CI: 1.71-3.65) for C. pneumoniae and H. pylori, respectively. Raised CRP levels had an OR of 3.85 (95% CI: 2.54-5.87). CONCLUSION: Although our study indicates the role of infections in the etiology of AMI in study population, the relative public health impact of these agents in the overall prevalence of AMI needs urgent research attention.

Asunto(s)

RESUMEN

BACKGROUND: The study was undertaken to estimate the effectiveness of BCG vaccination in relation to scar size in the prevention of tuberculosis and leprosy. METHODS: The present study was designed as hospital-based pair-matched case-control study and was carried out at Government Medical College Hospital, Nagpur, Maharashtra, India. It included 877 cases of tuberculosis and 292 cases of leprosy (diagnosed by WHO criteria), born onwards 1962. Each case was pair-matched with one control for age, sex and socio-economic status. BCG vaccination status was assessed by examination for the presence of BCG scar, immunisation records if available and information from subjects/parents of children. Subjects uncertain about BCG vaccination were not included. The diameter of the BCG scar was measured both across and along the arm in millimeters using a plastic ruler. The average was then calculated. RESULTS: A significant protective association between BCG vaccination and tuberculosis (OR=0.38, 95% CI 0.31-0.47) and leprosy (OR = 0.38, 95% CI 0.26-0.55) was observed. The overall vaccine effectiveness (VE) was 62% (95% CI 53-69) against tuberculosis and 62% (95% CI 45- against leprosy. Vaccine effectiveness against tuberculosis and leprosy was non-significantly greater in the group who had BCG scar size < or =5 mm as compared to subjects who had BCG scar size > 5 mm. Thus there was no clear association between BCG scar size and its effectiveness. CONCLUSION: The current study did not identify any significant association between BCG scar size and its effectiveness against tuberculosis or leprosy.

Asunto(s)

RESUMEN

OBJECTIVE: To study association between the geographic location (latitude) of studies evaluating protective effect of BCG vaccine and it's efficacy / effectiveness against tuberculosis. METHODS: A comprehensive literature search was carried out to identify relevant studies. Data extraction from these studies included place of study (geographic latitude), study design and reported point estimate of protective effect of BCG vaccine against tuberculosis. Information on latitude was obtained from Oxford School Atlas for World Geography. A spearman rank correlation coefficient was estimated to study the association between the latitude of studies and protective effect of BCG vaccine. RESULTS: The Spearman's rank correlation coefficient was significant for all studies grouped together & trials and marginally non-significant for other observational studies. However it was not statistically significant for case-control studies and cohort studies. Overall rho (for 80 studies) between latitude and protective effect of BCG was calculated to be 0.3853 (p = 0.0004). The results thus demonstrated that, in general BCG appeared to provide greater protection at higher latitudes. Thus a correlation coefficient of 0.3853 between latitude and protective effect would indicate that (0.3853)(2) or 15% of the variance in protective effect was accounted for by latitude. CONCLUSION: The study recognized an association between geographic locations of studies and reported protective effects of BCG vaccine against tuberculosis.

Asunto(s)

RESUMEN

A hospital-based, pair-matched, casecontrol study was carried out at Government Medical College Hospital in Nagpur in central India to estimate the effectiveness of BCG vaccination in the prevention of leprosy. The study included 314 incidence cases of leprosy [diagnosed by World Health Organization (WHO) criteria] below the age of 32 years. Each case was pair matched with one control for age, sex and socioeconomic status. Controls were selected from subjects attending this hospital for conditions other than tuberculosis and leprosy. A significant protective association between BCG and leprosy was observed (OR 0.29, 95% CI 0.21-0.41). The vaccine effectiveness (VE) was estimated to be 71% (95% CI 59-79). The BCG effectiveness against multibacillary and paucibacillary leprosy was 79% (95% CI 60-89) and 67% (95% CI 45-78), respectively. It was more effective during the first decade of life (VE 74%; 95% CI 38-90), among females (VE 82%; 95% CI 64-90), and in the lower socioeconomic strata (VE 75%; 95% CI 32-92). The prevented fraction was calculated to be 51% (95% CI 38-62). In conclusion, this study has identified a beneficial role of BCG vaccination in the prevention of leprosy in central India.

Asunto(s)