In Vitro and In Vivo Anti-Salmonella Evaluation of Pectin Extracts and Hydrolysates from "Cas Mango" (Spondias dulcis).

BACKGROUND: The threat to human health posed by multidrug-resistant strains of Salmonella typhi (S. typhi) and Salmonella paratyphi (S. paratyphi) is of growing concern. Generally, there has been increasing resistance and even multidrug resistance to almost all classes of antibiotics. This has rendered treatment with antibiotics difficult and costly. The present study investigated the bioactivity of pectin and pectin hydrolysates derived from a local fruit, Spondias dulcis, against four strains of Salmonellae. METHODS: Pectin was extracted from alcohol extractives-free peel by acidic hydrolysis at a temperature of 80°C for one hour at pH 2 and 4. The pectin was precipitated with 95% alcohol at an extract to alcohol ratio of 1:10 v/v. Antimicrobial activity was determined using agar well diffusion technique. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were determined using the broth dilution technique. An in vivo study was then carried out with the bioactive extracts against the most resistant bacteria strain, to fully establish the therapeutic effect of these extracts. Balb/C mice were used, and ciprofloxacin was the positive control antibiotic. The extracts were administered to mice at two doses, 5mg/Kg and 10mg/Kg. The efficacy of extracts in the treatment of typhoid was evaluated based on survival rate, change in body weight, and change in bacteria load. RESULTS: Only one of the extracts (crude pectin pH 2.5) was active against all the Salmonellae by well diffusion, and the growth inhibition varied from 12mm to 15mm at100 µg/ml. Three of the extracts (crude pectin pH 2.5, pH 4, 12h hydrolysate, and pH 4, 1h hydrolysate) had MIC and MBC against all four Salmonellae strains with MIC ranging from 5.68 to 44.45 µg/ml and MBC from 11.36 to 44.45 µg/mL. Three treatments, namely, the pH4-12 hr, hydrolysate at 10mg/Kg and 5mg/Kg, and the pH4-1hr, hydrolysate at 10mg/Kg, had therapeutic effects against Salmonella infection in mice. CONCLUSION: The present study highlights the potential of pectin oligosaccharides as new source of anti-Salmonella drugs. Further investigations including exploration of mechanism of action of the most active pectin extracts/hydrolysates are envisaged.

In vitro and in vivo studies on anti-malarial activity of Commiphora africana and Dichrostachys cinerea used by the Maasai in Arusha region, Tanzania.

BACKGROUND: Traditional medicinal plants are one of the potential sources of anti-malarial drugs and there is an increasing interest in the use and development of traditional herbal remedies for the treatment of malaria and other ailments. This study was carried out with the aim to investigate the phytochemical screening, cytotoxic effect and antiplasmodial activities of Dichrostachys cinerea and Commiphora africana. Both plants are used by the Maasai in Tanzania in suspected malaria and other diseases. No previous work appears to have investigated the potential anti-malarial activity of the two plants. METHODS: This study aimed to investigate the in vitro anti-malarial activity of methanol and dichloromethane extracts of the two plants against chloroquine sensitive (D6) and chloroquine resistant (Dd2) strains of Plasmodium falciparum. The anti-malarial property was assessed by the lactate dehydrogenase method (pLDH). The in vivo anti-malarial study was carried out using the Peters' 4-day suppressive test in Plasmodium berghei in Balb/c mice. Cytotoxic tests were carried out using monkey kidney epithelial cell line in [3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Qualitative phytochemical screening was carried out using standard methods of analysis. RESULTS: The phytochemical screening of plant extracts revealed the presence of alkaloids, flavonoids, tannins, steroids, triterpenoids, glycosides and saponins. However, alkaloids were absent in most plant extracts. The dichloromethane extracts of C. africana (stem bark); D. cinerea (stem bark) and methanol extracts of D. cinerea (whole stem) all showed promising in vitro anti-malarial activities. All other extracts did not show any significant anti-malarial activity. The two most promising extracts based on in vitro studies, DCM extracts of C. africana (stem bark) and D. cinerea (stems bark), equally exhibited very significant anti-malarial activities in the mouse model. They exhibited parasite suppression rates of 64.24 and 53.12%, respectively, and considerable improvement in weight and survival rate. Most plant extracts were not cytotoxic except for DCM extract of D. cinerea (whole stem) CC50 (29.44 µg/mL). CONCLUSION: The findings of this study provide scientific evidence supporting the traditional use of the plants in the treatment of malaria by the Maasai in Arusha region, Tanzania. Consequently, further work including bioassay-guided fractionation and advanced toxicity testing may yield new anti-malarial drug candidates from the two plants.

Prevalence and associations of microalbuminuria in proteinuria-negative patients with type 2 diabetes in two regional hospitals in Cameroon: a cross-sectional study.

BACKGROUND: Microalbuminuria (MA) is the earliest clinical evidence of diabetic nephropathy, but most patients in sub-Saharan Africa (SSA) only have access to much cheaper dipstick proteinuria as a means to screen for diabetic nephropathy. The aim of this study was to determine the prevalence and associations of MA among proteinuria-negative type 2 diabetic patients in a SSA setting. METHODS: In this cross-sectional study, patients with type 2 diabetes screened negative for dipstick proteinuria in a primary healthcare hospital were assessed. Detection of microalbuminuria was carried out in two steps: qualitative detection using special microalbumin urine strip, and quantitative laboratory measurement and calculation of urinary albumin-to-creatinine ratio (UACR). Microalbuminuria was defined as UACR of 30-300 mg/g. RESULTS: A total of 162 type 2 diabetic patients were included. Using quantitative assessment, the prevalence of microalbuminuria was 14.2% (95% CI 8.8-19.6) whereas 26.5% (95% CI 19.8-34.0) had microalbuminuria with urine strip. The mean systolic blood pressure (p = 0.032), diastolic blood pressure (p = 0.032) and serum creatinine concentration (p < 0.001) were higher in people with microalbuminuria as compared to those with normoalbuminuria, whereas the mean body mass index (p = 0.046) and mean eGFR (p < 0.001) were lower in the albuminuria group. In multiple linear regression, eGFR (p = 0.001) and serum creatinine concentration (p = 0.003) were independently associated with increased UACR. CONCLUSIONS: One in every seven proteinuria-negative type 2 diabetic patients has microalbuminuria in primary care setting in Cameroon; microalbuminuria is associated with higher systolic and diastolic blood pressure, and declining kidney function. Our results emphasize the urgent need to increase the accessibility to microalbuminuria testing to ensure that all diabetic patients with negative dipstick proteinuria can benefit.

Antimicrobial Activities of a Plethora of Medicinal Plant Extracts and Hydrolates against Human Pathogens and Their Potential to Reverse Antibiotic Resistance.

Microbial infections till date remain a scourge of humanity due to lack of vaccine against some infections, emergence of drug resistant phenotypes, and the resurgence of infections amongst others. Continuous quest for novel therapeutic approaches remains imperative. Here we (i) assessed the effects of extracts/hydrolates of some medicinal plants on pathogenic microorganisms and (ii) evaluated the inhibitory potential of the most active ones in combination with antibiotics. Extract E03 had the highest DZI (25 mm). Extracts E05 and E06 were active against all microorganisms tested. The MICs and MBCs of the methanol extracts ranged from 16.667 × 10(3) µg/mL to 2 µg/mL and hydrolates from 0.028 to 333333 ppm. Extract E30 had the highest activity especially against S. saprophyticus (MIC of 6 ppm) and E. coli (MIC of 17 ppm). Combination with conventional antibiotics was shown to overcome resistance especially with E30. Analyses of the extracts revealed the presence of alkaloids, flavonoids, triterpenes, steroids, phenols, and saponins. These results justify the use of these plants in traditional medicine and the practice of supplementing decoctions/concoctions with conventional antibiotics. Nauclea pobeguinii (E30), the most active and synergistic of all these extracts, and some hydrolates with antimicrobial activity need further exploration for the development of novel antimicrobials.

Control of malaria and other vector-borne protozoan diseases in the tropics: enduring challenges despite considerable progress and achievements.

Vector-borne protozoan diseases represent a serious public health challenge, especially in the tropics where poverty together with vector-favorable climates are the aggravating factors. Each of the various strategies currently employed to face these scourges is seriously inadequate. Despite enormous efforts, vaccines-which represent the ideal weapon against these parasitic diseases-are yet to be sufficiently developed and implemented. Chemotherapy and vector control are therefore the sole effective attempts to minimize the disease burden. Nowadays, both strategies are also highly challenged by the phenomenon of drug and insecticide resistance, which affects virtually all interventions currently used. The recently growing support from international organizations and governments of some endemic countries is warmly welcome, and should be optimally exploited in the various approaches to drug and insecticide research and development to overcome the burden of these prevalent diseases, especially malaria, leishmaniasis, Human African Trypanosomiasis (HAT), and Chagas disease.

The Burden of Orphans and Vulnerable Children Due to HIV/AIDS in Cameroon.

HIV/AIDS is a major public health problem in Cameroon and Africa, and the challenges of orphans and vulnerable children are a threat to child survival, growth and development. The HIV prevalence in Cameroon was estimated at 5.1% in 2010. The objective of this study was to assess the burden of orphans and vulnerable children due to HIV/AIDS in Cameroon. A structured search to identify publications on orphans and other children made vulnerable by AIDS was carried out. A traditional literature search on google, PubMed and Medline using the keywords: orphans, vulnerable children, HIV/AIDS and Cameroon was conducted to identify potential AIDS orphans publications, we included papers on HIV prevalence in Cameroon, institutional versus integrated care of orphans, burden of children orphaned by AIDS and projections, impact of AIDS orphans on Cameroon, AIDS orphans assisted through the integrated care approach, and comparism of the policies of orphans care in the central African sub-region. We also used our participatory approach working experience with traditional rulers, administrative authorities and health stakeholders in Yaounde I and Yaounde VI Councils, Nanga Eboko Health District, Isangelle and Ekondo Titi Health Areas, Bafaka-Balue, PLAN Cameroon, the Pan African Institute for Development-West Africa, Save the orphans Foundation, Ministry of Social Affairs, and the Ministry of Public Health. Results show that only 9% of all OVC in Cameroon are given any form of support. AIDS death continue to rise in Cameroon. In 1995, 7,900 people died from AIDS in the country; and the annual number rose to 25,000 in 2000. Out of 1,200,000 orphans and vulnerable children in Cameroon in 2010, 300,000(25%) were AIDS orphans. Orphans and the number of children orphaned by AIDS has increased dramatically from 13,000 in 1995 to 304,000 in 2010. By 2020, this number is projected to rise to 350,000. These deaths profoundly affect families, which often are split up and left without any means of support. Similarly, the death of many people in their prime working years hamper the economy. Businesses are adversely affected due to the need to recruit and train new staff. Health and social service systems suffer from the loss of health workers, teachers, and other skilled workers. OVC due to HIV/AIDS are a major public health problem in Cameroon as the HIV prevalence continues its relentless increase with 141 new infections per day. In partnership with the Ministry of Social Affairs and other development organizations, the Ministry of Public Health has been striving hard to provide for the educational and medical needs of the OVC, vocational training for the out-of- school OVC and income generating activities for foster families and families headed by children. A continous multi-sectorial approach headed by the government to solve the problem of OVC due to AIDS is very important. In line with the foregoing, recommendations are proposed for the way forward.