New synchronization method for <i>Plasmodium falciparum</i>

&lt;b&gt;Background&lt;/b&gt;: Plasmodium falciparum is usually asynchronous during in vitro culture. Although various synchronization methods are available, they are not able to narrow the range of ages of parasites. A newly developed method is described that allows synchronization of parasites to produce cultures with an age range as low as 30 minutes. &lt;b&gt;Methods&lt;/b&gt;: Trophozoites and schizonts are enriched using Plasmion. The enriched late stage parasites are immobilized as a monolayer onto plastic Petri dishes using concanavalin A. Uninfected erythrocytes are placed onto the monolayer for a limited time period, during which time schizonts on the monolayer rupture and the released merozoites invade the fresh erythrocytes. The overlay is then taken off into a culture flask, resulting in a highly synchronized population of parasites. &lt;b&gt;Results&lt;/b&gt;: Plasmion treatment results in a 10- to 13-fold enrichment of late stage parasites. The monolayer method results in highly synchronized cultures of parasites where invasion has occurred within a very limited time window, which can be as low as 30 minutes. The method is simple, requiring no specialized equipment and relatively cheap reagents. &lt;b&gt;Conclusions&lt;/b&gt;: The new method for parasite synchronization results in highly synchronized populations of parasites, which will be useful for studies of the parasite asexual cell cycle

Pasting properties of high-quality cassava flour of some selected improved cassava varieties in Tanzania for baking

Open Access ArticlePartial substituting wheat with high-quality cassava flour (HQCF) in bread making would be economically beneficial in Tanzania. However, cassava varieties with the best pasting quality for this use are unknown. In addition, the appropriate time of harvesting the varieties to attain the best pasting quality is also unknown. This study, therefore, aimed at identifying the most appropriate cassava varieties and their appropriate harvesting time that could be used for production of HQCF for baking bread. Nine improved cassava varieties namely Kiroba, Mkuranga1, Pwani, Chereko, Mkumba, Hombolo, Orela, Kizimbani and Kipusa and two local varieties, Albert and Kibandameno were planted in 2020/2021 and 2021/2022 seasons at TARI-Ukiriguru using a split plot design. Harvesting was done at 10 and 12 months after planting (MAP). Pasting characteristics of the HQCF samples were determined at the International Centre of Tropical Agriculture, Dar es salaam, Tanzania using Perten Rapid Visco Analyzer (RVA) Tecmaster equipment, Model: N103802. The results indicated that KIPUSA had the lowest significant setback, while Hombolo had the highest significant setback both at 10 and 12 MAP suggesting that HQCF produced from KIPUSA should be considered for partial substitution of wheat in baking bread that is attractive to consumers

Rifapentine and isoniazid for prevention of tuberculosis in people with diabetes (PROTID): protocol for a randomised controlled trial.

BACKGROUND: Diabetes mellitus (DM) increases the risk of tuberculosis (TB) and will hamper global TB control due to the dramatic rise in type 2 DM in TB-endemic settings. In this trial, we will examine the efficacy and safety of TB preventive therapy against the development of TB disease in people with DM who have latent TB infection (LTBI), with a 12-week course of rifapentine and isoniazid (3HP). METHODS: The 'Prevention of tuberculosis in diabetes mellitus' (PROTID) consortium will randomise 3000 HIV-negative eligible adults with DM and LTBI, as evidenced by a positive tuberculin skin test or interferon gamma release assay, to 12 weeks of 3HP or placebo. Participants will be recruited through screening adult patients attending DM clinics at referral hospitals in Tanzania and Uganda. Patients with previous TB disease or treatment with a rifamycin medication or isoniazid (INH) in the previous 2 years will be excluded. The primary outcome is the occurrence of definite or probable TB disease; secondary outcome measures include adverse events, all-cause mortality and treatment completion. The primary efficacy analysis will be intention-to-treat; per-protocol analyses will also be carried out. We will estimate the ratio of TB incidence rates in intervention and control groups, adjusting for the study site using Poisson regression. Results will be reported as efficacy estimates (1-rate ratio). Cumulative incidence rates allowing for death as a competing risk will also be reported. Approximately 1000 LTBI-negative, HIV-negative participants will be enrolled consecutively into a parallel cohort study to compare the incidence of TB in people with DM who are LTBI negative vs positive. A number of sub-studies will be conducted among others to examine the prevalence of LTBI and active TB, estimate the population impact and cost-effectiveness of LTBI treatment in people living with DM in these African countries and address gaps in the prevention and therapeutic management of combined TB-DM. DISCUSSION: PROTID is anticipated to generate key evidence to guide decisions over the use of TB preventive treatment among people with DM as an important target group for better global TB control. TRIAL REGISTRATION: ClinicalTrials.gov NCT04600167 . Registered on 23 October 2020

Indicators of optimal diabetes care and burden of diabetes complications in Africa: a systematic review and meta-analysis.

OBJECTIVE: Contemporary data on the attainment of optimal diabetes treatment goals and the burden of diabetes complications in adult populations with type 2 diabetes in Africa are lacking. We aimed to document the current status of attainment of three key indicators of optimal diabetes care and the prevalence of five diabetes complications in adult African populations with type 2 diabetes. METHODS: We systematically searched Embase, PubMed and the Cochrane library for published studies from January 2000 to December 2020. Included studies reported any information on the proportion of attainment of optimal glycated haemoglobin (HbA1c), blood pressure (BP) and low-density lipoprotein cholesterol (LDLC) goals and/or prevalence of five diabetes complications (diabetic peripheral neuropathy, retinopathy, nephropathy, foot ulcers and peripheral arterial disease). Random effect model meta-analysis was performed to determine the pooled proportion of attainment of the three treatment goals and the prevalence of five diabetes complications. RESULTS: In total, 109 studies with a total of 63 890 participants (53.3% being females) were included in the meta-analysis. Most of the studies were conducted in Eastern African countries (n=44, 40.4%). The pooled proportion of attainment of an optimal HbA1c, BP and LDLC goal was 27% (95% CI 24 to 30, I2=94.7%), 38% (95% CI 30 to 46, I2=98.7%) and 42% (95% CI 32 to 52, I2=97.4%), respectively. The pooled prevalence of diabetic peripheral neuropathy, retinopathy, diabetic nephropathy, peripheral arterial disease and foot ulcers was 38% (95% CI 31 to 45, I2=98.2%), 32% (95% CI 28 to 36, I2=98%), 31% (95% CI 22 to 41, I2=99.3%), 19% (95% CI 12 to 25, I2=98.1%) and 11% (95% CI 9 to 14, I2=97.4%), respectively. CONCLUSION: Attainment of optimal diabetes treatment goals, especially HbA1c, in adult patients with type 2 diabetes in Africa remains a challenge. Diabetes complications, especially diabetic peripheral neuropathy and retinopathy, are highly prevalent in adult populations with type 2 diabetes in Africa

Burden and associated phenotypic characteristics of tuberculosis infection in adult Africans with diabetes: a systematic review.

Diabetes mellitus (DM) increases the risk of developing tuberculosis infection (TBI). However, the evidence on the burden and phenotypic characteristics of TBI in African patients with DM is limited. This study aimed to determine the prevalence and characterisation of TBI in native African patients living with DM. We searched PubMed, EMBASE, and African Journals Online for original studies reporting information on the prevalence and characteristics of TBI in adult Africans with DM. A forest plot was used to describe the pooled prevalence estimate of TBI and the corresponding 95% confidence intervals (CI). Six studies conducted in four African countries involving 721 participants with DM were included in this systematic review. The pooled prevalence estimate of TBI was 40% (95% CI 20-60%, I2 = 98.52%, p < 0.001). Age ≥ 40 years and glycated haemoglobin levels independently predicted TBI positivity in patients with DM in three studies. Africans with DM have a high prevalence of TBI, especially those who are older or with poorly controlled diabetes. This justifies the need for studies to explore how to screen and manage TBI to avert the progression to active TB disease

High Resistance of Plasmodium falciparum to Sulphadoxine/Pyrimethamine in Northern Tanzania and the Emergence of dhps Resistance Mutation at Codon 581

BACKGROUND: Sulphadoxine-pyrimethamine (SP) a widely used treatment for uncomplicated malaria and recommended for intermittent preventive treatment of malaria in pregnancy, is being investigated for intermittent preventive treatment of malaria in infants (IPTi). High levels of drug resistance to SP have been reported from north-eastern Tanzania associated with mutations in parasite genes. This study compared the in vivo efficacy of SP in symptomatic 6-59 month children with uncomplicated malaria and in asymptomatic 2-10 month old infants. METHODOLOGY AND PRINCIPAL FINDINGS: An open label single arm (SP) standard 28 day in vivo WHO antimalarial efficacy protocol was used in 6 to 59 months old symptomatic children and a modified protocol used in 2 to 10 months old asymptomatic infants. Enrolment was stopped early (87 in the symptomatic and 25 in the asymptomatic studies) due to the high failure rate. Molecular markers were examined for recrudescence, re-infection and markers of drug resistance and a review of literature of studies looking for the 581G dhps mutation was carried out. In symptomatic children PCR-corrected early treatment failure was 38.8% (95% CI 26.8-50.8) and total failures by day 28 were 82.2% (95% CI 72.5-92.0). There was no significant difference in treatment failures between asymptomatic and symptomatic children. 96% of samples carried parasites with mutations at codons 51, 59 and 108 in the dhfr gene and 63% carried a double mutation at codons 437 and 540. 55% carried a third mutation with the addition of a mutation at codon 581 in the dhps gene. This triple: triple haplotype maybe associated with earlier treatment failure. CONCLUSION: In northern Tanzania SP is a failed drug for treatment and its utility for prophylaxis is doubtful. The study found a new combination of parasite mutations that maybe associated with increased and earlier failure. TRIAL REGISTRATION: ClinicalTrials.gov NCT00361114

The gut microbiota: a major player in the toxicity of environmental pollutants?

Exposure to environmental chemicals has been linked to various health disorders, including obesity, type 2 diabetes, cancer and dysregulation of the immune and reproductive systems, whereas the gastrointestinal microbiota critically contributes to a variety of host metabolic and immune functions. We aimed to evaluate the bidirectional relationship between gut bacteria and environmental pollutants and to assess the toxicological relevance of the bacteria–xenobiotic interplay for the host. We examined studies using isolated bacteria, faecal or caecal suspensions—germ-free or antibiotic-treated animals—as well as animals reassociated with a microbiota exposed to environmental chemicals. The literature indicates that gut microbes have an extensive capacity to metabolise environmental chemicals that can be classified in five core enzymatic families (azoreductases, nitroreductases, β-glucuronidases, sulfatases and β-lyases) unequivocally involved in the metabolism of >30 environmental contaminants. There is clear evidence that bacteria-dependent metabolism of pollutants modulates the toxicity for the host. Conversely, environmental contaminants from various chemical families have been shown to alter the composition and/or the metabolic activity of the gastrointestinal bacteria, which may be an important factor contributing to shape an individual’s microbiotype. The physiological consequences of these alterations have not been studied in details but pollutant-induced alterations of the gut bacteria are likely to contribute to their toxicity. In conclusion, there is a body of evidence suggesting that gut microbiota are a major, yet underestimated element that must be considered to fully evaluate the toxicity of environmental contaminants