Difference in susceptibility to malaria between two sympatric ethnic groups in Mali

We compared malaria indicators among sympatric groups to study human heterogeneities in the response to Plasmodium falciparum malaria infection. Four cross-sectional surveys and two longitudinal surveys in two sympatric ethnic groups (Dogon and Fulani) in Mali were carried out from 1998 to 2000. Spleen and parasite rates were evaluated during the cross-sectional surveys and disease incidence was assessed during longitudinal surveys. In spite of similar sociocultural factors and entomologic inoculation rates between ethnic groups, the Fulani had a significantly higher spleen enlargement rate, lower parasite rate, and were less affected by the disease than the Dogon group, whose frequency of hemoglobin C was higher than that recorded among the Fulani group. The Fulani group had significantly higher levels of IgG and IgE against crude malaria antigen than the Dogon group, suggesting a role of anti-malaria antibodies in the immune protection seen in this group.     

The effects of intranasal dexmedetomidine premedication in children: a systematic review and meta-analysis

Purpose

Intranasal dexmedetomidine premedication is a newly introduced method for reducing stress and anxiety before general anesthesia in children. We performed a meta-analysis to identify the effects of intranasal dexmedetomidine premedication in children.

Source

We conducted a systematic review to find published randomized-controlled trials using intranasal dexmedetomidine as premedication. We searched databases in EMBASE?, MEDLINE®, and the Cochrane Controlled Trials Register using the Ovid platform. This study was conducted based on the Cochrane Review Methods.

Principal findings

This review included 1,168 participants in 13 studies. Intranasal dexmedetomidine premedication provided more satisfactory sedation at parent separation (relative risk [RR], 1.45; 95% confidence interval [CI], 1.19 to 1.76; P = 0.0002; I² = 80%) than other premedication regimes. In addition, it reduced the need for rescue analgesics (RR, 0.58; 95% CI, 0.40 to 0.83; P = 0.003; I² = 0%). Nevertheless, there were no differences in sedation at mask induction (RR, 1.25; 95% CI, 0.98 to 1.59; P = 0.08; I² =71%) or in the incidence of emergence delirium (RR, 0.52; 95% CI, 0.24 to 1.13; P = 0.10; I² = 67%). Intranasal dexmedetomidine was associated with a significantly lower incidence of nasal irritation (RR, 0.05; 95% CI, 0.01 to 0.36; P = 0.003; I² = 0%) and postoperative nausea and vomiting (RR, 0.63; 95% CI, 0.40 to 0.99; P = 0.04; I² = 0%) than other premedication treatments. It also showed significantly lower systolic blood pressure (weighted mean difference [WMD], ?6.7 mmHg; 95% CI, ?10.5 to ?2.9; P = 0.0006; I² = 96%) and heart rate (WMD, ?6.8 beats·min^?1; 95% CI, ?11.3 to ?2.6; P = 0.002; I² = 98%).

Conclusions

Intranasal dexmedetomidine provided more satisfactory sedation at parent separation and reduced the need for rescue analgesics and the incidence of nasal irritation and postoperative nausea and vomiting when compared with other premedication treatments.

     

Expression of Vimentin and Cytokeratin in Eutopic and Ectopic Endometrium of Women with Adenomyosis and Ovarian Endometrioma

PROBLEM: To determine the expression of vimentin and cytokeratin in eutopic and ectopic endometrium of women with both adenomyosis and ovarian endometrioma and to evaluate their cyclic changes during the menstrual cycle. METHOD OF STUDY: Twenty patients requiring hysterectomy with salpingo-oophorectomy were studied by immunohistochemistry according to their menstrual cycles. RESULTS: Cyclic expression of vimentin was noted in eutopic endometrium and adenomyosis, but not in endometrioma. Cytokeratin expression did not change during the menstrual cycles. The mean intensities of epithelial vimentin were significantly different from each other, being the lowest in endometrioma, intermediate in adenomyosis, and the highest in eutopic endometrium. There was no significant difference in intensities of cytokeratin between adenomyosis and endometrioma, but these intensities were significantly lower than that of eutopic endometrium. CONCLUSIONS: Lower intensities of cytokeratin in adenomyosis and endometrioma than in eutopic endometrium suggest that the ectopic endometria may have a lower degree of differentiation regardless of the site. The lower intensity of epithelial vimentin in endometrioma than in adenomyosis during the proliferative phase may reflect decreased functional activity, probably because of a pressure effect on the lining epithelium within the endometrioma.     

Analysis of the human antibody response to thrombospondin-related anonymous protein of Plasmodium falciparum.

Thrombospondin-related anonymous protein (TRAP) of the malaria parasite Plasmodium falciparum shares two sequence motifs with other proteins which possess adhesive properties. Recently, findings indicate that TRAP is an antigen which contributes to antisporozoite immunity. We have cloned and expressed the TRAP coding sequences in Escherichia coli to investigate the human humoral immune response against this protein in a region of malaria endemicity of West Africa characterized by a seasonal transmission. Our results show that antibodies against TRAP are present in infected individuals. The anti-TRAP antibodies were analyzed in both a longitudinal and a prospective study. The longitudinal analysis shows seasonal fluctuations of the levels of specific antibodies as well as age-dependent quantitative differences. The immune response is long-lived in most of the adults and some of the older children but short-lived in young children. More importantly, the prospective analysis suggests that the presence of anti-TRAP antibodies in older children before the beginning of malaria transmission correlates with the subsequent control of parasite densities.     

A molecular marker for chloroquine-resistant falciparum malaria

BACKGROUND: Chloroquine-resistant Plasmodium falciparum malaria is a major health problem, particularly in sub-Saharan Africa. Chloroquine resistance has been associated in vitro with point mutations in two genes, pfcrt and pfmdr 1, which encode the P. falciparum digestive-vacuole transmembrane proteins PfCRT and Pgh1, respectively. METHODS: To assess the value of these mutations as markers for clinical chloroquine resistance, we measured the association between the mutations and the response to chloroquine treatment in patients with uncomplicated falciparum malaria in Mali. The frequencies of the mutations in patients before and after treatment were compared for evidence of selection of resistance factors as a result of exposure to chloroquine. RESULTS: The pfcrt mutation resulting in the substitution of threonine (T76) for lysine at position 76 was present in all 60 samples from patients with chloroquine-resistant infections (those that persisted or recurred after treatment), as compared with a base-line prevalence of 41 percent in samples obtained before treatment from 116 randomly selected patients (P<0.001), indicating absolute selection for this mutation. The pfmdr 1 mutation resulting in the substitution of tyrosine for asparagine at position 86 was also selected for, since it was present in 48 of 56 post-treatment samples from patients with chloroquine-resistant infections (86 percent), as compared with a base-line prevalence of 50 percent in 115 samples obtained before treatment (P<0.001). The presence of pfcrt T76 was more strongly associated with the development of chloroquine resistance (odds ratio, 18.8; 95 percent confidence interval, 6.5 to 58.3) than was the presence of pfmdr 1 Y86 (odds ratio, 3.2; 95 percent confidence interval, 1.5 to 6.8) or the presence of both mutations (odds ratio, 9.8; 95 percent confidence interval, 4.4 to 22.1). CONCLUSIONS: This study shows an association between the pfcrt T76 mutation in P. falciparum and the development of chloroquine resistance during the treatment of malaria. This mutation can be used as a marker in surveillance for chloroquine-resistant falciparum malaria.     

Oblique decision trees for spatial pattern detection: optimal algorithm and application to malaria risk

Background  

In order to detect potential disease clusters where a putative source cannot be specified, classical procedures scan the geographical area with circular windows through a specified grid imposed to the map. However, the choice of the windows' shapes, sizes and centers is critical and different choices may not provide exactly the same results.     

Reduction of Squalene Epoxidase by Cholesterol Accumulation Accelerates Colorectal Cancer Progression and Metastasis

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Malaria and primary education in Mali: A longitudinal study in the village of Donéguébougou

This article assesses the role of malaria and certain social determinants on primary education, especially on educational achievement in Donéguébougou, a small village in a malaria-endemic area near Bamako, Mali. Field data was collected by the authors between November 2007 and June 2008 on 227 schoolchildren living in Donéguébougou. Various malaria indicators and econometric models were used to explain the variation in cognitive abilities, teachers’ evaluation scores, school progression and absences. Malaria is the primary cause of school absences. Fixed-effects estimates showed that asymptomatic malaria and the presence of falciparum malaria parasites had a direct correlation with educational achievement and cognitive performance. The evidence suggests that the correlation is causal.