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云南省边境地区疟疾防治资源分配分析 总被引:2,自引:2,他引:0
目的 分析云南省边境地区疟疾资源分配状况与疟疾传播的关系,为合理分配疟疾资源提供依据。方法 收集中老、中缅、中越边境地区有关疟疾统计资料,研究导致疟疾流行的危险因素。结果 结果表明来自国外和国内的波及效应数值和强度效应综合反映了这些边境县所面临的潜在疟疾传播危险因素。结论 该地区的疟疾防治资源分配不合理,有待进一步改善。 相似文献
3.
P. Carnevale P. Guibert S. Manguin 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2010,104(7):484-489
The purpose of our entomological survey was to estimate mosquito biodiversity, infectivity rates and insecticide resistance levels in Anopheles species in four study sites in a mining area with high malaria transmission in southeastern Guinea. Anopheles gambiae s.l. (77%) was the most common Anopheles collected followed by An. funestus (20%). The specimens of the An. gambiae complex were predominantly An. gambiae S form (97.6%) with 1.4% of An. gambiae M form found in Kérouané only, and 1% of An. arabiensis which was present in all four study sites. Anopheles gambiae S form and An. funestus were found to be infected with Plasmodium falciparum, with infectivity rates of 4.1% and 4.4% and inoculation rates of 0.60 and 0.19 infected bite/person/night, respectively. In addition, a high level (79%) of the knockdown resistance (kdr) L1014F mutation was reported in the populations of An. gambiae S form. The high malaria transmission that occurs in the prospected area of Guinea requires a long-term vector control programme. However, such a control programme will have to consider the presence of the kdr gene at a surprisingly high level within the dominant vector, which could reduce the expected impact of vector control. 相似文献
4.
2001年广西疟疾防治效果及流行特征分析 总被引:3,自引:0,他引:3
目的:分析2001年全区疟疾防治效果、流行趋势、流行特征,为疟疾防治与监测提供依据。方法:对全区2001年疟疾监测结果和调查结果资料进行分析研究。结果:2001年全区疟疾发病率、居民原虫阳性率分别比上年降低21.74%及16.67%,91.49%的当地感染的病人分布在山区县,86.02%的病灶村为1例病人。流动人口检出疟疾病例数占各类人群血检检出疟疾病例总数的87.89%,外出回归人员检出病例中84.79%的病人从事与野外作业相关的工种。结论:全区大部分地区为低疟区,局部地区疟疾传播仍未阻断。流动人口和山区复媒地区是当前疟疾监测的重点。 相似文献
5.
Merozoites of the malaria parasite Plasmodium falciparum possess on their surface proteolytically processed fragments of the merozoite surface protein-1 (MSP1). Secondary processing of one of these fragments, MSP142, always occurs prior to, or at the point of successful erythrocyte reinvasion. It is shown that a product of this secondary processing, MSP133, is shed in the form of a noncovalently-associated complex with a number of other proteins, including the MSP1-derived species MSP138 and MSP183. Secondary processing of MSP142, is inhibited by the chelating agents ethylenediaminetetraacetic acid (EDTA) and ethyleneglycol-bis-(β-aminoethyl ether)-tetraacetic acid (EGTA), and this inhibition is reversible by addition of excess calcium. Secondary processing occurs in preparations of washed, disrupted merozoites, and is inhibited by the protease inhibitors phenylmethylsulphonyl fluoride (PMSF) and diisopropyl fluorophosphate (DFP), indicating that the protease responsible is a membrane-associated serine protease. 相似文献
6.
Danila Valmori Jackeline F. Romero Ying Men Janet L. Maryanski Pedro Romero Giampietro Corradin 《European journal of immunology》1994,24(6):1458-1462
We have previously demonstrated that it is possible to induce a consistent and strong cytolytic T lymphocyte (CTL) response to synthetic peptides, corresponding to poorly immunogenic malaria CTL epitopes, by co-injecting them with peptides representing defined T helper (Th) epitopes in incomplete Freund's adjuvant (IFA). In this study we have tested different immunization protocols to improve further the elicitation of the CTL response. We show that the CTL response to a mixture of Th + CTL peptides administered in IFA was further enhanced by a previous injection of the Th epitope peptide in IFA. Moreover, we found that the response could be significantly augmented by a pre-injection of IFA alone. This enhancement was observed only if the Th epitope was also present in the second injection. The number of lymph node cells recovered was 2–3-fold higher in mice pre-injected with IFA, but the increase in specific CTL activity, expressed as lytic units per animal, by pre-injection of IFA was at least 10–20-fold. Thus, pre-injection of IFA clearly increases the magnitude of a subsequent CTL response. 相似文献
7.
A subcellular fraction enriched in erythrocyte membranes has been isolated from rhesus monkey erythrocytes infected with Plasmodium knowlesi. Infected cells were lysed by centrifugation through a zone of hypotonic buffer and membranes isolated by equilibrium density gradient centrifugation in the same tube. The purified membrane fraction was shown to include the erythrocyte surface membrane by several methods: electron microscopy, identification of Coomassie Blue stained erythrocyte membrane proteins, identification of band 3 with a monoclonal antibody, and identification of radioiodinated cell surface proteins. The resulting ghosts were shown to be specifically reactive with monkey sera against the variant surface antigens of P. knowlesi by indirect immunofluorescence and membrane agglutination. No reactivity was seen with a monoclonal antibody (13C11) against the intracellular schizont surface. A number of metabolically labelled parasite proteins were enriched in this membrane function, including peptides of 277, 208, 173, 153, 134, 109, 80, 60 and 48 kDa and the variant surface antigens of variable molecular mass (180-207 kDa). These proteins were distinct from the major parasite proteins of total infected erythrocytes and isolated merozoites. The major glucosamine labelled glycoprotein of the internal schizont (230 kDa) was not found in this fraction. Moreover, no fragment of this parasite glycoprotein was found in this membrane fraction, indicating that no part of this molecule is transported to the erythrocyte surface. In contrast, the variant antigen of P. knowlesi, known to be on the erythrocyte surface, could be readily identified as peptides unique to specific cloned parasite lines. We propose that the other nine parasite proteins found within this membrane fraction represent a starting point for the identification of other parasite proteins transported to the surface membrane of the infected erythrocyte. 相似文献
8.
Hansen DS Siomos MA De Koning-Ward T Buckingham L Crabb BS Schofield L 《European journal of immunology》2003,33(9):2588-2598
CD1d-restricted NKT cells are a novel T cell lineage with unusual features. They co-express some NK cell receptors and recognize glycolipid antigens through an invariant T cell receptor (TCR) in the context of CD1d molecules. Upon activation through the TCR, NKT cells produce large amounts of IFN-gamma and IL-4. It has been proposed that rapid cytokine output by activated NKT cells may induce bystander activation of other lymphoid lineages. The impact of CD1d-restricted NKT cell activation in the induction of B cell-mediated immune responses to infection is still unclear. We show here that CD1-restricted NKT cells contribute to malarial splenomegaly associated with expansion of the splenic B cell pool and enhance parasite-specific antibody formation in response to Plasmodium berghei infection. The increased B cell-mediated response correlates with the ability of NKT cells to promote Th2 immune responses. Additionally, antibody responses against the glycosylphosphatidylinositol (GPI)-anchored protein merozoite surface protein 1 (MSP-1) were found to be significantly lower in CD1(-/-) mice compared to wild-type animals. P. berghei-infected MHC class II (MHCII)(-/-) mice also generated antibodies against MSP-1, suggesting that antibody production against GPI-anchored antigens in response to malaria infection can arise from both MHCII-dependent and independent pathways. 相似文献
9.
David R. Allred Charles R. Sterling Philip D. Morse 《Molecular and biochemical parasitology》1983,7(1):27-39
The fluidity of Plasmodium berghei-infected mouse red cell membranes is increased over that of uninfected cells at both 24°C and 37°C. This was demonstrated by electron spin resonance spectroscopy using the hydrocarbon spin labels 2-dodecyl-2′,5,5′-trimethyloxazolidine-N-oxyl and 2-heptyl-2′ -hexyl-5,5′-dimethyloxazolidine-N-oxyl to label regions of the bilayer near its surface, and deeper within the hydrocarbon region, respectively. Arrhenius plots of the ‘empirical motion parameter’ (Ri) obtained from 2-heptyl-2′-hexyl-5,5′-dimethyloxazolidine-N-oxyl-labeled cells versus temperature over the range from 0 to 45°C showed an hysteretic behavior of the spin labels in the membranes of both mature and immature uninfected cells. Such hysteretic behavior was consistently lacking in membranes of infected cells. These differences in membrane fluidity and spin label behavior are interpreted to reflect biochemical modifications of the red cell membrane which occur with infection by the malarial parasite. 相似文献
10.
伯氏疟原虫对青蒿素抗药性的研究 总被引:1,自引:0,他引:1
仿Peters剂量递增法用伯氏疟原虫ANKA株及N株对QHS进行了抗药性的研究。经14个月的培育至第58代,QHS im注射“4日抑制性实验”的ED50在RQ/ANKA系及RQ/N系分别为其亲代系的53.4及54.6倍,但经蚊传未获成功。在第40代(I50=25)时,其50%的治愈剂量为其亲代系的5.4倍。停药传代其抗性会逐渐消失。该虫系对青蒿酯钠及蒿甲醚有明显的交叉抗性,其ED50分别为其亲代系的13.1及11.7倍,对伯喹的抗性为2.9倍,对氯喹未见明显交叉抗性。 相似文献