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11.
Measurement of viral load in plasma remains the best marker for the follow-up of antiretroviral therapy. However, its use is limited in developing countries due to the lack of adequate facilities and equipment, and cryopreservation of plasma during storage and transportation. Practical and reliable methods adapted to field conditions for the collection, transportation and accurate measurement of HIV-1 viral load are needed for the optimum use of antiretroviral therapy in resource-limited countries. This study evaluated the use of dried blood spots (DBS) for the real-time quantitation of HIV-1 RNA levels with the NucliSENS EasyQ((R)) HIV-1 assay (bioMérieux, Lyon, France) under field conditions in Senegal (Africa). Dried blood spots and plasma from 41 patients living in suburban Dakar were used for determination of HIV-1 RNA concentrations and stability at 37 degrees C. Analysis was performed at the Dakar University Hospital laboratory. Extraction was done with the bioMérieux NucliSENS((R)) miniMAGtrade mark, and real-time detection was done with the bioMérieux NucliSENS((R)) EasyQ system. HIV-1 RNA concentrations in plasma were compared with concentrations in dried blood spots after 8 and 15 days at 37 degrees C. The study showed a strong concordance in RNA levels between plasma and dried blood spots, which appear to be very stable over time with no apparent degradation observed after 2 weeks at 37 degrees C (mean difference 0.065logIU/ml). These results suggest that the use of dried blood spots in combination with the NucliSENS EasyQ HIV-1 assay is well adapted for HIV-1 RNA level monitoring in centralized laboratories in developing countries.  相似文献   
12.
Although domestic animals may not be permissive for Plasmodium, they could nevertheless play a role in the epidemiology of malaria by attracting Anopheles away from humans. To investigate interactions between domestic animals and mosquitoes, we assayed immunoglobulin G (IgG) antibodies directed against the salivary proteins of Anopheles gambiae in domestic animals living in Senegalese villages where malaria is endemic. By Western blotting, sera from bovines (n=6), ovines (n=36), and caprines (n=36) did not react with Anopheles whole saliva. In contrast, equine sera recognized proteins in both saliva and salivary gland extracts. Two of the major immunogens (32 and 72 kDa) were also reactive in extracts from other major mosquito genera (Aedes and Culex), but reactions toAnopheles-specific antigens were detected in 12 of 17 horses. These data suggest that horses strongly react to Anopheles bites, and further experiments on horses are warranted to investigate the impact of this domestic animal species on the transmission of human malaria.  相似文献   
13.
Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum drug resistance. There is an urgent need to investigate new sources of antimalarial drugs which are more effective against Plasmodium falciparum. One of the potential sources of antimalarial drugs is traditional medicinal plants. In this work, we studied the in vitro antiplasmodial activity of chloromethylenic, methanolic, and MeOH/H2O (1/1) crude extracts and decoction obtained from eight medicinal plants collected in Burkina Faso and of total alkaloids for five plants. Extracts were evaluated in vitro for efficacy against Plasmodium falciparum strain K1, which is resistant to chloroquine, pyrimethamine and proguanil using the fluorescence-based SYBR Green I assay. The antiproliferative activity on human-derived hepatoma cell line HepG2 and Chinese hamster ovary (CHO) cells was evaluated using the 3-[4,5-dimethylthyazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test in order to determine the selectivity index. Among the plant extracts tested for in vitro antiplasmodial activity, 16 were considered to be inactive (with IC50?>?10 μg/ml), six showed a moderate activity (5?<?IC50?≤?10 μg/ml), and six were found to have a good in vitro activity with IC50 value?≤?5 μg/ml. The highest antiplasmodial activity was found for extracts from: the alkaloid leaf extract and the chloromethylenic extracts of Combretum fragrans (IC50?=?3 μg/ml, IC50?=?5 μg/ml), the total alkaloids and the chloromethylenic leaf extracts of Combretum collinum (IC50?=?4 μg/ml), the MeOH/H2O leaf extract of Terminalia avicennioides (IC50?=?3.5 μg/ml), and the alkaloid leaf extract of Pavetta crassipes (IC50?=?5 μg/ml). Three other extracts showed moderate antiplasmodial activity (5?<?IC50?≤?10 μg/ml): Terminalia avicennioides and Combretum fragrans methanolic extracts and Acacia kirkii alkaloid leaf extract (IC50?=?6.5, 9 and 10 μg/ml respectively). The Terminalia avicennioides crude MeOH/H2O (80:20 v/v) extract of the leaves was submitted to a successive liquid/liquid extraction with ethylacetate and n-butanol respectively. The extracts were investigated for in vitro antiplasmodial activity and antioxidant properties using DPPH, ABTS+ and FRAP methods. The ethylacetate extract showed the best antiplasmodial activity (7 μg/ml) and the active constituent was isolated as ellagic acid by bioguided fractionation with an IC50?=?0.2 μM on Plasmodium falciparum and SI?=?152. Besides, Terminalia avicennioides leaf extract and ellagic acid showed a good antioxidant activity. Our finding confirms the importance of investigating the antimalarial activity of plant species used in traditional medicine. Overall, two plants belonging to the Combretaceae family, Combretum fragrans and Combretum collinum appeared to be the best candidates and will be further investigated for their antiplasmodial properties, in order to isolate the molecules responsible for the antiplasmodial activity.  相似文献   
14.
Undifferentiated embryonal sarcoma of the liver is rare. It is usually observed in children and adolescents. We report one case of embryonal sarcoma of the liver arising in patient without any antecedent. The only symptom was right scapular pain. The liver scan showed a multicystic lesion suspicious for infectious origin or a tumor. Serologies for ecchinococcus, schistosomiasis and brucellosis were negative. The treatment was a right hepatectomy. On gross examination, the tumor was unencapsulated, multicystic and contained large areas of necrosis admixed with gelatinous areas. Microscopically, there were epithelioid and spindle tumor cells in a myxo?d stroma. Lipoblastic-like or rhabdomyoblastic-like, giant cells and PAS positive hyaline globules in the cell cytoplasm were present. The tumor cells expressed vimentin, cytokeratin (KL1), alpha-1-antitrypsin and smooth muscle actin. This observation shows that embryonal sarcoma of the liver may develop in adult patients and should be taken into consideration in any differential diagnosis of cystic hepatic tumor.  相似文献   
15.
OBJECTIVES: Human immunodeficiency virus type 2 (HIV-2) progression to disease is significantly slower than that of human immunodeficiency virus type 1 (HIV-1). Genetic determinants for susceptibility to disease progression were hypothesized to play a more significant role in this infection compared with HIV-1. We sought to identify common human lymphocyte antigen (HLA) alleles in the Senegalese population and to compare HLA profiles between HIV-2-infected individuals with low and high risk for disease progression. STUDY DESIGN/METHODS: We conducted a case-control study investigating possible associations between MHC class I genes and the risk of disease progression in HIV-2-infected individuals. The MHC class I genotype was molecularly defined using polymerase chain reaction with sequence specific primers (PCR-SSP) in 62 female sex workers from the Dakar, Senegal cohort. Lack of antibodies to the HIV-2 antigen p26 has been previously shown to predict disease progression and was used in this study as a surrogate marker. Twenty-one cases were identified lacking antibodies to p26, therefore at a higher risk of disease progression, and were compared with 41 p26 antibody-positive, randomly selected controls. RESULTS: Statistical analysis showed that HLA B35 was significantly associated with lack of p26 antibodies, and higher risk of disease progression ( < 0.05). The same association was found for the self-defined class I haplotypes B35-Cw4 and A23-Cw 7 ( < 0.05). The HLA B 53 allele was associated with slower disease progression; however, this association was not statistically significant. We observed a trend whereby heterozygotes were at lower risk for HIV-2 disease progression, as previously reported in HIV-1 disease. CONCLUSIONS: In this West African population, a distinct profile of HLA class I alleles was observed, and many of these appear to influence disease progression in HIV-2 infection.  相似文献   
16.
Cerebral malaria (CM) is a neurological complication of infection with Plasmodium falciparum that is partly caused by cytokine-mediated inflammation. It is not known whether interleukin-17 (IL-17) cytokines, which regulate inflammation, control the development of CM. To evaluate the involvement of IL-17 cytokines in CM, we analyzed 46 common polymorphisms in IL17A, IL17F, and IL17RA (which encodes the common receptor chain of the members of the IL-17 family) in two independent African populations. A case-control study involving 115 Nigerian children with CM and 160 controls from the community (CC) showed that IL17F reference single nucleotide polymorphism (SNP) 6913472 (rs6913472) (P = 0.004; odds ratio [OR] = 3.12), IL17F rs4715291 (P = 0.004; OR = 2.82), IL17RA rs12159217 (P = 0.01; OR = 2.27), and IL17RA rs41396547 (P = 0.026; OR = 3.15) were independently associated with CM. A replication study was performed in 240 nuclear Malian family trios (two parents with one CM child). We replicated the association for 3 SNPs, IL17F rs6913472 (P = 0.03; OR = 1.39), IL17RA rs12159217 (P = 0.01; OR = 1.52), and IL17RA rs41396547 (P = 0.04; OR = 3.50). We also found that one additional SNP, IL17RA rs41433045, in linkage disequilibrium (LD) with rs41396547, was associated with CM in both Nigeria and Mali (P = 0.002; OR = 4.12 in the combined sample). We excluded the possibility that SNPs outside IL17F and IL17RA, in strong LD with the associated SNPs, could account for the observed associations. Furthermore, the results of a functional study indicated that the aggravating GA genotype of IL17F rs6913472 was associated with lower IL-17F concentrations. Our findings show for the first time that IL17F and IL17RA polymorphisms modulate susceptibility to CM and provide evidence that IL-17F protects against CM.  相似文献   
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19.
The traditional products used to treat some pains can cause serious complications of which surgical abdomen. We listed in two years five cases of surgical abdomen complicating a traditional treatment in the service of digestive and general surgery of the hospital complex Yalgado Ouédraogo. There were two men and three women with an average age of 34,4 years. These traditional products were used to treat constipation, sexual impotence, sterility and to “posses” her husband. Oral and rectal routes were used by one and three patients respectively, another patient used triple routes (oral, rectal and vaginal). The digestive lesions were in the upper tract in one case (gastric phytobezoar), two patients presented acute intestinal occlusion and two others acute generalized peritonitis. All the five patients underwent laparotomy. Two patients died in immediately post-operative course. The prevention of severe surgical complications of the digestive tract induced by traditional treatments has to be broadcasted through information, education and communication.  相似文献   
20.

Background

Despite the use of combined antiretroviral therapy, HIV-infected individuals have a higher risk of developing B-cell lymphoma compared to the general population. We aim to explore whether lymphocyte activation, increase in Th1 response as well as markers of EBV reactivation, may precede lymphoma diagnosis.

Methods

Thirteen cases and 26 controls matched on CD4+ T-cell count and HIV plasma viral load were identified. Samples were collected 0 to 5 years prior to B-cell lymphoma diagnosis. Seven out of 13 (54 %) and 16/26 (61.5 %) of cases and controls were receiving antiretroviral therapy at the time of sampling, respectively. CD8+ T-cell activation and Th1 cytokine concentrations were measured before lymphoma onset, together with IgG antibodies directed against viral capsid antigen (VCA) and serum levels of EBV DNA.

Results

A higher level of CD8+ T-cell activation was observed in patients developing lymphoma. Four out of seven Th1 cytokine serum concentrations were significantly higher in patients with lymphoma than in the control group: IL-2R, IL-12p40/70, IFN-γ-inducible protein 10 (IP-10) and monokine induced by IFN-γ (MIG). Anti-VCA IgG level were significantly higher in cases than in controls. Four cases (30 %) but no controls had detectable EBV DNA in serum.

Conclusion

A higher level of T-cell activation, Th1 cytokine serum concentration and markers of EBV replication, preceded B-cell lymphoma diagnosis. This may suggest that viral antigen stimulation is associated with the genesis of lymphoma in HIV-infected patients.  相似文献   
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