New acylated triterpenoid saponins from the roots of Acacia polyacantha Willd. (Fabaceae).

In our continuing search of saponins from the plants of Fabaceae family, phytochemical investigation of the roots of Acacia polyacantha, led to the isolation and structural characterization of six undescribed triterpenoid saponins, named polyacosides A-F (1-6). Their structures were established, using extensive analysis by NMR techniques, mainly 1D NMR (H, C, and DEPT) and 2D NMR (COSY, NOESY, HSQC, TOCSY and HMBC) experiments, HRESIMS and by comparison with the literature data, as 3-O-[β-d-xylopyranosyl-(1 → 4)- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)]-α-l-arabinopyranosyl]-21-O-[Cis-2-methoxycinnamoyl] machaerinic acid (1), 3-O-[β-d-xylopyranosyl-(1 → 4)- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)]-α-l-arabinopyranosyl]-21-O- [Cis-3,4-dimethoxycinnamoyl] machaerinic acid. (2), 3-O- [β-d-galactopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)-α-l-arabinopyranosyl]-21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (3), 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Cis-3,4-dimethoxycinnamoyl] machaerinic acid (4), 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Cis-2-methoxycinnamoyl] machaerinic acid (5) and 3-O- [β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl] -21-O- [Trans-4-methoxycinnamoyl] machaerinic acid (6).

Role of Anopheles (Cellia) rufipes (Gough, 1910) and other local anophelines in human malaria transmission in the northern savannah of Cameroon: a cross-sectional survey.

Background: As part of a study to determine the impact of insecticide resistance on the effectiveness of long-lasting insecticide treated nets (LLINs) in the north of Cameroon, the unexpectedly high density and anthropophilic behaviour of Anopheles rufipes lead us to investigate this species bionomics and role in human malaria parasite transmission.

Methods: For four consecutive years (2011-2014), annual cross-sectional sampling of adult mosquitoes was conducted during the peak malaria season (September-October) in three health districts in northern Cameroon. Mosquitoes sampled by human landing catch and pyrethrum spray catch methods were morphologically identified, their ovaries dissected for parity determination and Anopheles gambiae siblings were identified by molecular assay.

Anopheles ziemanni a locally important malaria vector in Ndop health district, north west region of Cameroon.

Background: Malaria transmission in Cameroon is mediated by a plethora of vectors that are heterogeneously distributed across the country depending on the biotope. To effectively guide malaria control operations, regular update on the role of local Anopheles species is essential. Therefore, an entomological survey was conducted between August 2010 and May 2011 to evaluate the role of the local anopheline population in malaria transmission in three villages of the Ndop health district in the northwest region of Cameroon where malaria is holoendemic, as a means to acquiring evidence based data for improved vector intervention.

Clinical, ultrasonographic, and pathologic characteristics of patients with chronic right-lower-quadrant abdominal pain that may benefit from appendectomy.

Background: Chronic pains of the right lower quadrant of the abdomen (RLQA) remain a challenging problem worldwide, especially in areas with limited technical background; chronic appendicitis is still a subject of controversy. The aim of this study was to analyze the clinical and paraclinical data of patients with chronic pains of RLQA who had an appendectomy performed.

Methods: During a period of 4 years, all patients presenting with a chronic pain of the RLQA were selected for our study and underwent clinical assessment and systematic ultrasonography of the abdomen; these served as a basis of selecting candidates for appendectomy.

The distribution of insecticide resistance in Anopheles gambiae s.l. populations from Cameroon: an update.

Insecticides are a key component of vector-based malaria control programmes in Cameroon. As part of ongoing resistance surveillance efforts, Anopheles gambiae s.l.

Relationship between kdr mutation and resistance to pyrethroid and DDT insecticides in natural populations of Anopheles gambiae.

The spread of insecticide resistance genes in Anopheles gambiae Giles sensu stricto threatens to compromise vector-based malaria control programs. Two mutations at the same locus in the voltage-gated sodium channel gene are known to confer knockdown resistance (kdr) to pyrethroids and DDT. Kdr-e involves a leucine-serine substitution, and it was until recently thought to be restricted to East Africa, whereas kdr-w, which involves a leucine-phenylalanine substitution, is associated with resistance in West Africa.

Malaria transmission and rice cultivation in Lagdo, northern Cameroon.

Cross-sectional entomological surveys were carried out during the 2006 dry and rainy seasons in Lagdo, Cameroon to measure the impact of rice cultivation on malaria transmission and to monitor vector susceptibility to insecticides. Adult anopheline mosquitoes were captured on human volunteers and by pyrethrum spray collections. A total of 4740 mosquitoes was collected during the study.