In vivo antiplasmodial activity of hydromethanolic leaf extract and solvent fractions of Maytenus gracilipes (Celastraceae) against Plasmodium berghei in mice

BACKGROUND

The incidence of resistance among currently available antimalarial drugs, as well as the high economic cost of malaria, has prompted researchers to look for novel antimalarial molecules. As a result, the current study was proposed to evaluate the antiplasmodial activity (in vivo) of Maytenus gracilipes based on the plant's traditional claims.

METHODS

A cold maceration procedure using 80% methanol as a solvent was employed to obtain a crude extract from M. gracilipes leaves. Chloroform, n-butanol, and pure water were used to fractionate the hydromethanolic extract. Standard procedures were followed for an acute oral toxicity test. The antimalarial effects of the plant at 200, 400, and 600 mg/kg doses were investigated using three rodent malaria models (4-day suppressive, rane's, and repository tests). Thirty mice were utilized in each experiment (3 treatment and 2 control groups, each with six mice). Parasitemia, survival time, body weight, temperature, and packed cell volume were all used to assess the extracts' antiplasmodial activity. To compare results between groups, a one-way ANOVA with Post Hoc Tukey's HSD was used.

RESULTS

In a 4-day suppressive investigation, all doses of the crude extract and fractions suppressed parasitemia significantly (P < 0.001) as compared to the negative control. The crude extract had the greatest chemosuppressive effect (74.15%) at 600 mg/kg dose. Chloroform had the greatest parasitemia suppression among the fractions; however it was less than the crude extract. In Rane's test, all doses of the crude extract produced substantial (P < 0.001) curative effects as compared to the negative control.

CONCLUSION

According to this study, the crude extract and solvent fractions of M. gracilipes leaves contain antimalarial activity with a substantial suppressive effect. The antiplasmodial effects were more active in the chloroform and n-butanol fractions, indicating that the plant's non-polar and medium polar constituents are responsible. Nonetheless, further analysis is required to isolate and characterize the active compounds responsible for the study plant's antimalarial activity.

How We Do Harm: Do Copyrighted Scales Benefit Research in the Developing World?

One of the most difficult challenges in carrying out global health research in the developing world is the issue of copyright protection of questionnaires. The current reality is that research in the developing world is often hampered by inadequate or even non-existent budgetary support. From our point of view, an additional hindrance to carrying out research in developing countries is the insistence by holders of questionnaire copyrights that they are paid for the use of their testing instruments. One adverse consequence of demands for compensation by copyright holders may be that worthwhile research is impeded or even prevented. It is argued that the practice of charging non-funded research projects for the use of copyrighted questionnaires denies inclusion of data on world minorities, and thus prevents the potential benefits that such data could provide. In this commentary, we focus on copyrighted instruments and the restrictions that they often represent for researchers in the developing world. More broadly, we argue that to the extent that research in the developing world is impeded by demands for developed world levels of compensation for the use of proprietary tests, the development of vital health programs that are designed to serve these populations can be adversely affected. Several strategies for rectifying inequities posed by current copyright policies are suggested for the promotion of health research in the developing world.

The global burden of tuberculosis: results from the Global Burden of Disease Study 2015

BACKGROUND

An understanding of the trends in tuberculosis incidence, prevalence, and mortality is crucial to tracking of the success of tuberculosis control programmes and identification of remaining challenges. We assessed trends in the fatal and non-fatal burden of tuberculosis over the past 25 years for 195 countries and territories.

METHODS

We analysed 10 691 site-years of vital registration data, 768 site-years of verbal autopsy data, and 361 site-years of mortality surveillance data using the Cause of Death Ensemble model to estimate tuberculosis mortality rates. We analysed all available age-specific and sex-specific data sources, including annual case notifications, prevalence surveys, and estimated cause-specific mortality, to generate internally consistent estimates of incidence, prevalence, and mortality using DisMod-MR 2.1, a Bayesian meta-regression tool. We assessed how observed tuberculosis incidence, prevalence, and mortality differed from expected trends as predicted by the Socio-demographic Index (SDI), a composite indicator based on income per capita, average years of schooling, and total fertility rate. We also estimated tuberculosis mortality and disability-adjusted life-years attributable to the independent effects of risk factors including smoking, alcohol use, and diabetes.

FINDINGS

Globally, in 2015, the number of tuberculosis incident cases (including new and relapse cases) was 10·2 million (95% uncertainty interval 9·2 million to 11·5 million), the number of prevalent cases was 10·1 million (9·2 million to 11·1 million), and the number of deaths was 1·3 million (1·1 million to 1·6 million). Among individuals who were HIV negative, the number of incident cases was 8·8 million (8·0 million to 9·9 million), the number of prevalent cases was 8·9 million (8·1 million to 9·7 million), and the number of deaths was 1·1 million (0·9 million to 1·4 million). Annualised rates of change from 2005 to 2015 showed a faster decline in mortality (-4·1% [-5·0 to -3·4]) than in incidence (-1·6% [-1·9 to -1·2]) and prevalence (-0·7% [-1·0 to -0·5]) among HIV-negative individuals. The SDI was inversely associated with HIV-negative mortality rates but did not show a clear gradient for incidence and prevalence. Most of Asia, eastern Europe, and sub-Saharan Africa had higher rates of HIV-negative tuberculosis burden than expected given their SDI. Alcohol use accounted for 11·4% (9·3-13·0) of global tuberculosis deaths among HIV-negative individuals in 2015, diabetes accounted for 10·6% (6·8-14·8), and smoking accounted for 7·8% (3·8-12·0).

INTERPRETATION

Despite a concerted global effort to reduce the burden of tuberculosis, it still causes a large disease burden globally. Strengthening of health systems for early detection of tuberculosis and improvement of the quality of tuberculosis care, including prompt and accurate diagnosis, early initiation of treatment, and regular follow-up, are priorities. Countries with higher than expected tuberculosis rates for their level of sociodemographic development should investigate the reasons for lagging behind and take remedial action. Efforts to prevent smoking, alcohol use, and diabetes could also substantially reduce the burden of tuberculosis.

FUNDING

Bill & Melinda Gates Foundation.

Global, Regional, and National Cancer Incidence, Mortality, Years of Life Lost, Years Lived With Disability, and Disability-Adjusted Life-years for 32 Cancer Groups, 1990 to 2015: A Systematic Analysis for the Global Burden of Disease Study

IMPORTANCE

Cancer is the second leading cause of death worldwide. Current estimates on the burden of cancer are needed for cancer control planning.

OBJECTIVE

To estimate mortality, incidence, years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs) for 32 cancers in 195 countries and territories from 1990 to 2015.

EVIDENCE REVIEW

Cancer mortality was estimated using vital registration system data, cancer registry incidence data (transformed to mortality estimates using separately estimated mortality to incidence [MI] ratios), and verbal autopsy data. Cancer incidence was calculated by dividing mortality estimates through the modeled MI ratios. To calculate cancer prevalence, MI ratios were used to model survival. To calculate YLDs, prevalence estimates were multiplied by disability weights. The YLLs were estimated by multiplying age-specific cancer deaths by the reference life expectancy. DALYs were estimated as the sum of YLDs and YLLs. A sociodemographic index (SDI) was created for each location based on income per capita, educational attainment, and fertility. Countries were categorized by SDI quintiles to summarize results.

FINDINGS

In 2015, there were 17.5 million cancer cases worldwide and 8.7 million deaths. Between 2005 and 2015, cancer cases increased by 33%, with population aging contributing 16%, population growth 13%, and changes in age-specific rates contributing 4%. For men, the most common cancer globally was prostate cancer (1.6 million cases). Tracheal, bronchus, and lung cancer was the leading cause of cancer deaths and DALYs in men (1.2 million deaths and 25.9 million DALYs). For women, the most common cancer was breast cancer (2.4 million cases). Breast cancer was also the leading cause of cancer deaths and DALYs for women (523 000 deaths and 15.1 million DALYs). Overall, cancer caused 208.3 million DALYs worldwide in 2015 for both sexes combined. Between 2005 and 2015, age-standardized incidence rates for all cancers combined increased in 174 of 195 countries or territories. Age-standardized death rates (ASDRs) for all cancers combined decreased within that timeframe in 140 of 195 countries or territories. Countries with an increase in the ASDR due to all cancers were largely located on the African continent. Of all cancers, deaths between 2005 and 2015 decreased significantly for Hodgkin lymphoma (-6.1% [95% uncertainty interval (UI), -10.6% to -1.3%]). The number of deaths also decreased for esophageal cancer, stomach cancer, and chronic myeloid leukemia, although these results were not statistically significant.

CONCLUSION AND RELEVANCE

As part of the epidemiological transition, cancer incidence is expected to increase in the future, further straining limited health care resources. Appropriate allocation of resources for cancer prevention, early diagnosis, and curative and palliative care requires detailed knowledge of the local burden of cancer. The GBD 2015 study results demonstrate that progress is possible in the war against cancer. However, the major findings also highlight an unmet need for cancer prevention efforts, including tobacco control, vaccination, and the promotion of physical activity and a healthy diet.

Treatment Outcomes of Nevirapine- Versus Efavirenz-Based Highly Active Antiretroviral Therapy Regimens Among Antiretroviral-Naive Adult Patients in Ethiopia: A Cohort Study

BACKGROUND

Despite wide use of nevirapine- and efavirenz-based highly active antiretroviral therapy regimens in Ethiopia, their treatment outcome has not been well studied. The objective of this study was to compare treatment outcome of nevirapine- and efavirenz-based regimens.

METHODS

This retrospective cohort study was conducted on antiretroviral-naive adult patients with human immunodeficiency virus (HIV) who had started antiretroviral therapy. Study participants were excluded after treatment failure, regimen change, loss to follow-up, or transfer to other health facility. The outcomes of interest included immunologic recovery, immunologic failure, clinical failure, and treatment failure.

RESULTS

There were 1064 HIV patients in the study; an equal proportion (1:1) from both efavirenz- and nevirapine-based regimens was included. Patients in both regimens had similar baseline CD4 cells count ( P = .876). In multivariate analysis, efavirenz-based regimens showed more likelihood of immunologic recovery, whether defined as a CD4 cell count of >200 cells/mm³ (hazard ratio [HR] = 1.31 [95% CI, 1.05-1.59]), >350 cells/mm³ (HR = 1.26 [95% CI, 1.08-1.47]), or >500 cells/mm³ (HR = 1.95 [95% CI, 1.57-2.41]). Moreover, efavirenz-based regimens showed a lower hazard of treatment failure (HR = 0.66 [95% CI, 0.49-0.88]).

CONCLUSION

Although the finding of retrospective study should be interpreted with caution, efavirenz-based regimens were associated with superior treatment outcome.