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41.
42.
目的了解宁波市江北区发热病人疟原虫血片质量,为镜检质量考核以及疟疾防治效果评价提供科学依据。方法对江北区各级医疗卫生单位已检血片进行随机抽样,抽取所有阳性血涂片和不少于10%的阴性血涂片进行复检。从血片制作、染色、清洁度方面对血片质量进行对比分析和评价。结果共抽查已检血片637张,血片制作、染色和清洁度总体合格率分别为86.03%、89.79%和89.64%,并有逐年增高的趋势。不同月份复检血片质量亦有显著性差异(P〈0.05)。血片质量缺陷以沉渣、厚膜制作不规范以及偏碱性为主。结论宁波市江北区疟原虫血片质量较好,基本达到考核标准。但仍需加强培训和指导,促进血片质量不断提高。 相似文献
43.
《Indian journal of medical microbiology》2016,34(2):193-197
Objective: The present study aims to find out the mutational prevalence of Plasmodium falciparum chloroquine resistance transporter (Pfcrt) gene in Assam and Arunachal Pradesh, India. Methods: To fulfil the objective of the study, a total of 54 P. falciparum malaria positive samples were attempted for genotyping of Pfcrt gene using polymerase chain reaction (PCR) and direct DNA sequencing method. Results: The K76T mutation was observed in 77.78% cases followed by M74I (61.11%), N75E (61.11%) and C72S (16.67%). Triple mutant allele M74I+N75E+K76T was found in 61.11% P. falciparum field isolates. Double mutant allele C72S+K76T was seen among 16.67% samples. Mutation studies have shown existence of three different haplotypes of which two were associated with chloroquine resistance. The haplotype CVIET was found preponderance and circulated in all four districts. The other haplotype SVMNT was observed only in Karbi Anglong district of Assam. Maximum haplotype diversity was also recorded from Karbi Anglong district of Assam. Conclusion: Our study has confirmed high prevalence of mutant Pfcrt genotypes associated with chloroquine resistance in Assam and Arunachal Pradesh, India. 相似文献
44.
Narumon Sereekhajornjaru Chanat Somboon Roonglawan Rattanajak William A. Denny Prapin Wilairat Saranya Auparakkitanon 《Acta tropica》2014
The hematin-targeting properties of pynacrine, an acridine analog of the schizontocidal antimalarial drug, pyronaridine, were evaluated to probe the role of the latter's benzonaphthyridine moiety. Pynacrine was as active as pyronaridine in inhibiting glutathione-induced hematin degradation and in enhancing hematin-mediated membrane lysis. It formed a 1:2 complex with hematin but was 50-fold less effective in inhibiting β-hematin formation. However, pynacrine was as potent as pyronaridine in inhibiting intra-erythrocytic Plasmodium falciparum growth in culture, suggesting that it has other off-target(s) effects. 相似文献
45.
Juan Carlos Quintana Castillo Leidy Johana Vargas Cesar Segura José María Gutiérrez Juan Carlos Alarcón Pérez 《Toxins》2012,4(12):1500-1516
The antimicrobial and antiparasite activity of phospholipase A2 (PLA2) from snakes and bees has been extensively explored. We studied the antiplasmodial effect of the whole venom of the snake Bothrops asper and of two fractions purified by ion-exchange chromatography: one containing catalytically-active phospholipases A2 (PLA2) (fraction V) and another containing a PLA2 homologue devoid of enzymatic activity (fraction VI). The antiplasmodial effect was assessed on in vitro cultures of Plasmodium falciparum. The whole venom of B. asper, as well as its fractions V and VI, were active against the parasite at 0.13 ± 0.01 µg/mL, 1.42 ± 0.56 µg/mL and 22.89 ± 1.22 µg/mL, respectively. Differences in the cytotoxic activity on peripheral blood mononuclear cells between the whole venom and fractions V and VI were observed, fraction V showing higher toxicity than total venom and fraction VI. Regarding toxicity in mice, the whole venom showed the highest lethal effect in comparison to fractions V and VI. These results suggest that B. asper PLA2 and its homologue have antiplasmodial potential. 相似文献
46.
47.
R. J. PLEASS 《Parasite immunology》2009,31(2):61-63
Immune complexes (ICs) are believed to play an important role in malaria pathology, and an interesting article by Mibei et al. recently published by Parasite Immunology suggests that IgG4 and IgE are particularly important. However, researchers should be aware of potential pitfalls to current assays aimed at measuring plasma ICs and correlating these to deposition in tissues. 相似文献
48.
MARKUS KAMBER‡ MICHAEL BLACKMAN§ PECK-SUN LIN JAMES BROWN† HILTON WHITTLE† RUPERT SCHMIDT-ULLRICH 《Parasite immunology》1992,14(4):451-456
Nine human monoclonal antibodies (MoAbs) recognizing 7 different antigenic structures of blood-stages of the human malarial parasite P. falciparum (Pf) were produced by Epstein-Barr virus transformed B-cell lines (EBV-TCL) with or without fusion to the lymphoblastoid cell line KR4. The peripheral blood B-lymphocytes were obtained from 8 Gambian donors immune to Pf malaria. Two of the EBV-TCL could be expanded and maintained for more than 6 months but neither one could be cloned. Six additional EBV-TCL were stabilized after fusion with the KR4 lymphoblastoid cell line. All resulting hybridomas permitted easy cloning. Some of the MoAbs produced distinct fluorescent staining patterns of asexual Pf blood-stage parasites when using high-resolution digitized video-intensified fluorescence microscopy. Antigens on 195 kD and 155 kD proteins were recognized by 3 and 1 MoAb, respectively, using Western blotting and immunoprecipitation techniques. 相似文献
49.
Summary The extent of reduced glutathione, activity of glutathione peroxidase, amount of membrane lipid peroxidation products, and the extent of hemoglobin release from host erythrocytes during in vitroPlasmodium falciparum growth was studied. Highly synchronized parasite cultures were studied to examine the alterations caused by different growth stages of the parasite. There was a moderate increase in the reduced glutathione content as the parasite matured, which was significant only in schizontrich erythrocyte lysates (p<0.05) whereas the activity of glutathione peroxidase was significantly low in all the parasitized red blood cells (ring-infected RBC,p<0.005; trophozoite- and schizont-infected RBC,p<0.001). The lipid peroxidation product, malonyldialdehyde, of the host red cells increased gradually to more than fourfold in schizont-rich cells as compared with normal erythrocytes (p<0.001). The hemoglobin release from cultured cells was significantly higher in all parasitized red cell cultures as well as in uninfected cells kept in in vitro, as compared with normal erythrocytes. The consequence of such changes induced by the malarial parasites in the host red cells in the pathogenesis of erythrocyte destruction and anemia ofP. falciparum malaria is discussed. 相似文献
50.
Chaiyaroj SC Rutta AS Muenthaisong K Watkins P Na Ubol M Looareesuwan S 《Acta tropica》2004,89(3):319-327
In the present study, we investigated plasma levels of interleukin (IL)-12 and transforming growth factor (TGF-beta1) in malaria patients as these two cytokines regulate the balance between pro- and anti-inflammatory cytokines. We compared plasma IL-12 and TGF-beta1 levels in groups of malaria patients categorized as uncomplicated, severe, cerebral and placental malaria. Both TGF-beta1 and IL-12 levels were significantly reduced in peripheral plasma of adults with severe and cerebral malaria as well as in plasma of Tanzanian children with cerebral malaria (P<0.05). Similar results were observed with both placental and peripheral plasma of pregnant women who were infected with Plasmodium falciparum. IL-18, a cytokine known to be critical for the induction of IFN-gamma along with IL-1, was produced more in uncomplicated adult patients than in aparasitimic healthy controls (P<0.05). However, IL-18 response rate declined as the symptoms of the disease became more severe suggesting that the IL-18 response may be impaired with increased malaria severity. Together, the results of the three cytokines support the notion that imbalance between pro- and anti-inflammatory cytokines may contribute to the development of severe malaria infection. With malaria infection during pregnancy, we demonstrated that macrophage migration inhibitory factor (MIF) levels in infected placental plasma were significantly higher than those in the paired peripheral plasma (P<0.05). MIF, therefore, may play an important role in the local immune response to placental P. falciparum infection. 相似文献