Malaria vectors and transmission dynamics in coastal south-western Cameroon

Background

Malaria is a major public health problem in Cameroon. Unlike in the southern forested areas where the epidemiology of malaria has been better studied prior to the implementation of control activities, little is known about the distribution and role of anophelines in malaria transmission in the coastal areas.

Methods

A 12-month longitudinal entomological survey was conducted in Tiko, Limbe and Idenau from August 2001 to July 2002. Mosquitoes captured indoors on human volunteers were identified morphologically. Species of the Anopheles gambiae complex were identified using the polymerase chain reaction (PCR). Mosquito infectivity was detected by the enzyme-linked immunosorbent assay and PCR. Malariometric indices (plasmodic index, gametocytic index, parasite species prevalence) were determined in three age groups (<5 yrs, 5–15 yrs, >15 yrs) and followed-up once every three months.

Results

In all, 2,773 malaria vectors comprising Anopheles gambiae (78.2%), Anopheles funestus (17.4%) and Anopheles nili (7.4%) were captured. Anopheles melas was not anthropophagic. Anopheles gambiae had the highest infection rates. There were 287, 160 and 149 infective bites/person/year in Tiko, Limbe and Idenau, respectively. Anopheles gambiae accounted for 72.7%, An. funestus for 23% and An. nili for 4.3% of the transmission. The prevalence of malaria parasitaemia was 41.5% in children <5 years of age, 31.5% in those 5–15 years and 10.5% in those >15 years, and Plasmodium falciparum was the predominant parasite species.

Conclusion

Malaria transmission is perennial, rainfall dependent and An. melas does not contribute to transmission. These findings are important in the planning and implementation of malaria control activities in coastal Cameroon and West Africa.

     

Curcumin mediated epigenetic modulation inhibits TREM-1 expression in response to lipopolysaccharide

Triggering receptor expressed on myeloid cells 1 (TREM-1) is a member of the immunoglobulin superfamily expressed on macrophage and neutrophils and is emerging as a potent amplifier of TLR initiated inflammatory responses. Blockade of TREM-1 improves survival in animal models of sepsis. In this study, we show that curcumin or diferuloylmethane, a yellow pigment present in turmeric, a major ingredient of curry spice inhibited the expression of TREM-1 in vitro in primary bone marrow derived macrophages and in vivo in lungs of mice with sepsis. Chromatin immunoprecipitation assay confirmed that curcumin inhibits the binding of p65 to TREM-1 promoter in response to LPS. Further we show that curcumin inhibited p300 activity in the TREM-1 promoter region leading to hypoacetylation of histone 3 and 4 in the lysine residues. Inhibition of TREM-1 by curcumin is oxidant independent. These studies are the first report to define a detailed molecular mechanism by which curcumin exerts anti-inflammatory effects through regulation of TREM-1 gene activity and provide additional mechanistic insights into the anti-inflammatory effect of curcumin.     

Ethanol production by genetically modified strains of Saccharomyces

Summary Two polyploid yeast strains and two genetically manipulated yeast strains were subjected to anaerobic fermentations in whole corn mash and defined media. Carbohydrate utilization and ethanol production rates were investigated. Whilst the polyploid strains exhibited superior performance in the whole corn mash, the genetically manipulated strains were so in defined media with glucose as the substrate. The overall fermentation performance of the novel strains however was comparable to the polyploid strains with corn mash as the substrate when most of the solid material had been removed. The flocculating and dextrin utilizing properties of the yeast strains examined play an important role in such fermentations.     

Mortality from an aspiration of dental crown during extraction

An aspiration of a dental crown during a dental extraction requires appropriate and timely diagnosis and management. While foreign body aspiration in dental procedures is relatively uncommon, it constitutes a true medical emergency and is associated with significant morbidity and mortality. We report a case of mortality from a foreign body aspiration and discuss the epidemiology, risk factors, signs and symptoms, management, and prevention of foreign body ingestion and aspiration events.     

Purification of Monomeric Prolactin Charge Isoform from Buffalo Pituitaries

Abstract

A standard protocol for isolation of buffalo prolactin (buPRL) was modified at the alcohol precipitation step. This modification could separate lower molecular weight prolactin from the higher molecular weight prolactin (PRL). Reloading the prolactin onto a Sephacryl S‐200 gel purified the buPRL monomer. The purity of buPRL monomer was confirmed by 15% SDS PAGE. The buPRL monomer was >90% pure. It was characterized by specific anti‐buPRL serum in ELISA and Western blot. A native PAGE of the PRL showed three charge isoforms. A protocol was standardized to separate prolactin monomeric least acidic isoforms using an anion exchanger.     

Increased osmotolerance of genetically modified ethanol producing strains of Saccharomyces Sp.

Summary A stable spheroplast fusion product of the polyploid brewing strain Saccharomyces uvarum (cares bergensis) , strain 21 and a genetically constructed diploid Saccharomyces diastaticus, strain 1384 has been shown to have improved ethanol producing capability in defined media (Panchal et al., 1982). This fusion product, strain 1400 was further subjected to fermentations in defined media containing glucose substrate and varying concentrations of the non-metabolized sugars sorbitol or mannitol.While the fermentation efficiencies of all the three strains decreased with increasing osmotic pressure imparted by sorbitol or mannitol, the detrimental effect was least apparent with the fusion product than with either of the fusion partners. This attribute of the stable fusion product has major significance in relation to its potential for industrial ethanol production.