A Comparative Investigation on Petroleum Demulsification Techniques (Centrifuge and Green Chemicals Versus Conventional Chemicals)

The breaking (demulsification) of 50-50% w/o petroleum emulsions of two oils (A and B) by Green (chemical and centrifuge) methods were studied in comparison to conventional (chemical) method. The green methods consisted of silicon based chemical demulsifiers and high-speed centrifuge operated at 12,000 RPM, while the conventional method consisted of Amine group based demulsifiers. In chemical method, the concentrations were varied (0.5%, 1.5% and 3%), while in centrifuge method, the processing time was varied (10 and 30 minutes). The efficiency of these methods was determined by measuring the amount of water separated from the emulsion after being treated. The maximum separation efficiencies for Silicon demulsifiers were 93 and 88% for oils A and B respectively, and that of Amine group demulsifiers were 72 and 86% for oils A and B respectively, While centrifuge demulsification gave maximum separations of 39 and 24% for oils A and B respectively. Based on these results, Silicon based demulsifiers are very effective and reliable method to treat emulsions for different types of oils with different composition, and have the potential to be used as an alternative method in the demulsification or breaking of water-in-crude oil emulsions

Different methodological approaches to the assessment of in vivo efficacy of three artemisinin-based combination antimalarial treatments for the treatment of uncomplicated falciparum malaria in African children.

BACKGROUND: Use of different methods for assessing the efficacy of artemisinin-based combination antimalarial treatments (ACTs) will result in different estimates being reported, with implications for changes in treatment policy. METHODS: Data from different in vivo studies of ACT treatment of uncomplicated falciparum malaria were combined in a single database. Efficacy at day 28 corrected by PCR genotyping was estimated using four methods. In the first two methods, failure rates were calculated as proportions with either (1a) reinfections excluded from the analysis (standard WHO per-protocol analysis) or (1b) reinfections considered as treatment successes. In the second two methods, failure rates were estimated using the Kaplan-Meier product limit formula using either (2a) WHO (2001) definitions of failure, or (2b) failure defined using parasitological criteria only. RESULTS: Data analysed represented 2926 patients from 17 studies in nine African countries. Three ACTs were studied: artesunate-amodiaquine (AS+AQ, N = 1702), artesunate-sulphadoxine-pyrimethamine (AS+SP, N = 706) and artemether-lumefantrine (AL, N = 518).Using method (1a), the day 28 failure rates ranged from 0% to 39.3% for AS+AQ treatment, from 1.0% to 33.3% for AS+SP treatment and from 0% to 3.3% for AL treatment. The median [range] difference in point estimates between method 1a (reference) and the others were: (i) method 1b = 1.3% [0 to 24.8], (ii) method 2a = 1.1% [0 to 21.5], and (iii) method 2b = 0% [-38 to 19.3].The standard per-protocol method (1a) tended to overestimate the risk of failure when compared to alternative methods using the same endpoint definitions (methods 1b and 2a). It either overestimated or underestimated the risk when endpoints based on parasitological rather than clinical criteria were applied. The standard method was also associated with a 34% reduction in the number of patients evaluated compared to the number of patients enrolled. Only 2% of the sample size was lost when failures were classified on the first day of parasite recurrence and survival analytical methods were used. CONCLUSION: The primary purpose of an in vivo study should be to provide a precise estimate of the risk of antimalarial treatment failure due to drug resistance. Use of survival analysis is the most appropriate way to estimate failure rates with parasitological recurrence classified as treatment failure on the day it occurs

Polymorphisms in Plasmodium falciparum chloroquine resistance transporter and multidrug resistance 1 genes: parasite risk factors that affect treatment outcomes for P. falciparum malaria after artemether-lumefantrine and artesunate-amodiaquine.

Adequate clinical and parasitologic cure by artemisinin combination therapies relies on the artemisinin component and the partner drug. Polymorphisms in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multidrug resistance 1 (pfmdr1) genes are associated with decreased sensitivity to amodiaquine and lumefantrine, but effects of these polymorphisms on therapeutic responses to artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) have not been clearly defined. Individual patient data from 31 clinical trials were harmonized and pooled by using standardized methods from the WorldWide Antimalarial Resistance Network. Data for more than 7,000 patients were analyzed to assess relationships between parasite polymorphisms in pfcrt and pfmdr1 and clinically relevant outcomes after treatment with AL or ASAQ. Presence of the pfmdr1 gene N86 (adjusted hazards ratio = 4.74, 95% confidence interval = 2.29 - 9.78, P < 0.001) and increased pfmdr1 copy number (adjusted hazards ratio = 6.52, 95% confidence interval = 2.36-17.97, P < 0.001 : were significant independent risk factors for recrudescence in patients treated with AL. AL and ASAQ exerted opposing selective effects on single-nucleotide polymorphisms in pfcrt and pfmdr1. Monitoring selection and responding to emerging signs of drug resistance are critical tools for preserving efficacy of artemisinin combination therapies; determination of the prevalence of at least pfcrt K76T and pfmdr1 N86Y should now be routine

Household food consumption and nutritional status of children aged 6 to 59 Months in Zinder, Niger Republic

Malnutrition exists in both urban and rural areas in Niger. An analysis of food and nutrition situation was carried out in the urban&nbsp; municipality of Zinder in order to contribute to a better understanding of the situation. This work was done from February to March 2018, at the household level, sampled by probabilistic method. The study involved 168 children from 6 to 59 months selected from 150 households in 15neighborhoods in the urban municipalities of Zinder. An analysis of the Food Consumption Score and Household Food Diversity Score showed acceptable food consumption and high food diversity respectively in58.7% and 67.3% of households. Furthermore, the results showed that the socio-economic characteristics that determined Score of food consumption were the main activities of heads of households and their wives. Food diversity was generally acceptable, although 2.7 % of households still had low dietary diversity in the study area. Also, food diversity remained low overall for nearly 8.9% of children with a rate of 6.0% for&nbsp; households headed by a woman. Nevertheless, the latter female-headed households had an estimated 13.7% of children with average individual food diversity. The prevalence of acute global malnutrition is 13.1% with the severe form at3%. It should be noted that girls were much more affected by this severe form (3.4%) compared to 2.5% for boys. However, stunting was more prevalent in males than in females with 57.5% and 46.6%,respectively. Moderate form accounting for 28.4% in females compared to 17.5% in males. This&nbsp; nutritional status reflects the relatively acceptable food situation in which these children lived. Furthermore, the appreciation of different foods and modes of consumption have shown on the one hand that the diet remains monotonous. On the other hand, this analysis revealed that cereal-based dishes accompanied by vegetable/leafy sauces predominated in these households in the study area. This situation exposes the members of these households and especially young children to the risk of malnutrition. Key words: Characterization, food consumption, food diversity, nutritional status, children, household, socioeconomics, Zinde

HRP2 and pLDH-Based Rapid Diagnostic Tests, Expert Microscopy, and PCR for Detection of Malaria Infection during Pregnancy and at Delivery in Areas of Varied Transmission: A Prospective Cohort Study in Burkina Faso and Uganda.

BACKGROUND: Intermittent screening and treatment (IST) of malaria during pregnancy has been proposed as an alternative to intermittent preventive treatment in pregnancy (IPTp), where IPTp is failing due to drug resistance. However, the antenatal parasitaemias are frequently very low, and the most appropriate screening test for IST has not been defined. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a multi-center prospective study of 990 HIV-uninfected women attending ANC in two different malaria transmission settings at Tororo District Hospital, eastern Uganda and Colsama Health Center in western Burkina Faso. Women were enrolled in the study in the second or third trimester of pregnancy and followed to delivery, generating 2,597 blood samples for analysis. Screening tests included rapid diagnostic tests (RDTs) targeting histidine-rich protein 2 (HRP2) and parasite lactate dehydrogenase (pLDH) and microscopy, compared to nPCR as a reference standard. At enrolment, the proportion of pregnant women who were positive for P. falciparum by HRP2/pan pLDH RDT, Pf pLDH/pan pLDH RDT, microscopy and PCR was 38%, 29%, 36% and 44% in Uganda and 21%, 16%, 15% and 35% in Burkina Faso, respectively. All test positivity rates declined during follow-up. In comparison to PCR, the sensitivity of the HRP2/pan pLDH RDT, Pf pLDH/pan pLDH RDT and microscopy was 75.7%, 60.1% and 69.7% in Uganda, 55.8%, 42.6% and 55.8% in Burkina Faso respectively for all antenatal visits. Specificity was greater than 96% for all three tests. Comparison of accuracy using generalized estimating equation revealed that the HRP2- detecting RDT was the most accurate test in both settings. CONCLUSIONS/SIGNIFICANCE: The study suggests that HRP2-based RDTs are the most appropriate point-of-care test currently available for use during pregnancy especially for symptomatic women, but will still miss some PCR-positive women. The clinical significance of these very low density infections needs to be better defined

PlasmoView: a web-based resource to visualise global Plasmodium falciparum genomic variation.

Malaria is a global public health challenge, with drug resistance a major barrier to disease control and elimination. To meet the urgent need for better treatments and vaccines, a deeper knowledge of Plasmodium biology and malaria epidemiology is required. An improved understanding of the genomic variation of malaria parasites, especially the most virulent Plasmodium falciparum (Pf) species, has the potential to yield new insights in these areas. High-throughput sequencing and genotyping is generating large amounts of genomic data across multiple parasite populations. The resulting ability to identify informative variants, particularly single-nucleotide polymorphisms (SNPs), will lead to the discovery of intra- and inter-population differences and thus enable the development of genetic barcodes for diagnostic assays and clinical studies. Knowledge of genetic variability underlying drug resistance and other differential phenotypes will also facilitate the identification of novel mutations and contribute to surveillance and stratified medicine applications. The PlasmoView interactive web-browsing tool enables the research community to visualise genomic variation and annotation (eg, biological function) in a geographic setting. The first release contains over 600,000 high-quality SNPs in 631 Pf isolates from laboratory strains and four malaria-endemic regions (West Africa, East Africa, Southeast Asia and Oceania)

Myrmécofaune arboricole associée aux couples Phragmanthera capitata (Sprengel) S. Balle/ hôte au verger de la chefferie de Ndogbong (Douala, Cameroun)

Parmi les Loranthaceae, l’espèce Phragmanthera capitata s’est mieux adaptée aux conditions du milieu modifié par l’homme et aux arbres cultivés ou spontanés devenant un véritable fléau agronomique. La méthode de lutte ciblée plus prometteuse ne peut être satisfaisante que si les mécanismes qui régulent l’adaptation des Loranthaceae à leurs hôtes cultivés ou spontanés sont identifiés et maîtrisés. Dans cette optique, une étude de la myrmécofaune arboricole a été menée sur trois couples P. capitata/hôte au verger de la chefferie de Ndogbong. Auparavant, un inventaire exhaustif de tous les arbres parasités ou non et de la myrmécofaune du verger de la chefferie de Ndogbong (Douala) a été entrepris et toutes les touffes de P. capitata comptabilisés sur les arbreshôtes qui en possédaient. Tous les arbres du verger sont exotiques excepté Spondias mangifera. Le taux de parasitisme est de 42,85%. Quatre espèces de fourmis (Crematogaster sp. 1, Crematogaster sp.2, Pheidole megacephala et Camponotus sp.) ont une activité fourragère notamment florifère sur les individus de P. capitata. Leur densité varie avec la floraison et semble liée à la chute des boutons floraux et des fleurs. Ces fourmis pourraient constituer des forces d’organisation et d’évolution exploitables dans la lutte biologique contre les Loranthaceae. Mots clés: Loranthaceae, myrmécofaune arboricole, plantes hôtes

Pharyngeal carriage of Neisseria species in the African meningitis belt.

OBJECTIVES: Neisseria meningitidis, together with the non-pathogenic Neisseria species (NPNs), are members of the complex microbiota of the human pharynx. This paper investigates the influence of NPNs on the epidemiology of meningococcal infection. METHODS: Neisseria isolates were collected during 18 surveys conducted in six countries in the African meningitis belt between 2010 and 2012 and characterized at the rplF locus to determine species and at the variable region of the fetA antigen gene. Prevalence and risk factors for carriage were analyzed. RESULTS: A total of 4694 isolates of Neisseria were obtained from 46,034 pharyngeal swabs, a carriage prevalence of 10.2% (95% CI, 9.8-10.5). Five Neisseria species were identified, the most prevalent NPN being Neisseria lactamica. Six hundred and thirty-six combinations of rplF/fetA_VR alleles were identified, each defined as a Neisseria strain type. There was an inverse relationship between carriage of N. meningitidis and of NPNs by age group, gender and season, whereas carriage of both N. meningitidis and NPNs was negatively associated with a recent history of meningococcal vaccination. CONCLUSION: Variations in the prevalence of NPNs by time, place and genetic type may contribute to the particular epidemiology of meningococcal disease in the African meningitis belt