Acta Leidensia最新文献_第3页

V-NOW! Symposium on genetic variation of malaria parasites: implications for selection of adequate control strategies. Leiden, The Netherlands, November 14-16, 1990. V-NOW !疟疾寄生虫遗传变异专题讨论会:对选择适当控制策略的影响。1990年11月14日至16日，荷兰莱顿。

Acta Leidensia Pub Date : 1991-01-01

引用次数: 0

Possible mechanisms for the maintenance of polymorphisms in Plasmodium populations. 疟原虫种群中多态性维持的可能机制。

Acta Leidensia Pub Date : 1991-01-01

D E Arnot

引用次数: 0

Malaria control during the nineties: what is to be expected? 九十年代的疟疾控制:可以期待什么?

Acta Leidensia Pub Date : 1991-01-01

H J van der Kaay

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Antigenic diversity in Plasmodium falciparum. 恶性疟原虫抗原多样性研究。

Acta Leidensia Pub Date : 1991-01-01

R F Anders

{"title":"Antigenic diversity in Plasmodium falciparum.","authors":"R F Anders","doi":"","DOIUrl":"","url":null,"abstract":"There are several mechanisms responsible for the extensive antigenic diversity found in the asexual blood stages of Plasmodium falciparum. Failure to express antigens is a feature of many isolates cultured in vitro but probably is not a major cause of antigenic diversity in vivo. Numerous point mutations occur in allelic forms of asexual blood stage antigens and are assumed to contribute to antigenic diversity but as yet few such mutations have been mapped to antigenic epitopes. A major cause of antigenic diversity is the expression of different repetitive sequences in allelic forms of several antigens including the S-antigen and the two merozoite surface antigens, MSA-1 and MSA-2. The sequencing data indicates that S-antigen genes fall into many allelic families whereas both MSA-1 and MSA-2 are dimorphic. Further diversity has arisen as a result of intragenic recombinations between the dimorphic forms of both MSA-1 and MSA-2. In addition to this diversity reflecting the expression of different allelic genes, asexual blood stages of malaria parasites undergo antigenic variation in that clonal parasite populations can vary the form of an antigen on the surface of infected erythrocytes. Antibodies or DNA probes directed against variable repeat sequences can be used to distinguish different isolates of P. falciparum. The use of antibodies to S-antigen repeats has been particularly useful for typing the parasites causing infections. The application of S-antigen typing to field studies in Papua New Guinea has demonstrated marked diversity in the parasites causing infections in one area.","PeriodicalId":7108,"journal":{"name":"Acta Leidensia","volume":"60 1","pages":"57-67"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12983784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Protective immune responses as indicators of antigenic diversity and stability. 保护性免疫反应作为抗原多样性和稳定性的指标。

Acta Leidensia Pub Date : 1991-01-01

K N Brown

引用次数: 0

The need for live parasites for long-term immunity in malaria. 疟疾长期免疫需要活寄生虫。

Acta Leidensia Pub Date : 1991-01-01

W M Eling, C Celluzzi, C C Hermsen, T van de Wiel, J Curfs, P L Liem

{"title":"The need for live parasites for long-term immunity in malaria.","authors":"W M Eling, C Celluzzi, C C Hermsen, T van de Wiel, J Curfs, P L Liem","doi":"","DOIUrl":"","url":null,"abstract":"All of the results of the various experiments support a role for living, proliferating parasites in the efficient induction of anti-parasitic as well as anti-disease (CM) immunity. Non-proliferating parasites or material from disrupted parasites are poor or non-antigens in this respect. Three possibilities as to why living parasites are important in immunity could be considered: 1. circulating parasites contain insufficient antigen to induce protective immunity, but sufficient antigen can be produced during proliferation; 2. only circulating parasites arrive at critical places (e.g. parts of the white pulp of the spleen) for the presentation of the important antigen or induction of appropriate signals. 3. Architectural changes are needed (i.e. formation of barrie-cell-complexes) for the immune response to be effective. The first possibility explains why exoantigens, as well as live, proliferating parasites are efficient inducers of anti-CM immunity. Since these immunizations have no effect on parasitemia, additional/other immune reaction(s) are needed for anti-parasitic immunity. The important role of the spleen in malaria and malaria immunity is well-known. The second possibility includes the idea that live, proliferating parasites circulate through the spleen continuously where unsatisfactory or infected erythrocytes are removed rather than in the liver. Injected killed parasites or material from them when present in the circulation is to a larger extent taken up by the Kupffer cells from the liver rather than the spleen. Presence and uptake of parasites in the spleen may provide the critical confrontation and/or delivery of signals necessary for the development of immunity.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":7108,"journal":{"name":"Acta Leidensia","volume":"60 1","pages":"167-75"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12983775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A live attenuated malaria vaccine: science or fiction? 减毒疟疾活疫苗:科学还是虚构?

Acta Leidensia Pub Date : 1991-01-01

B Mons

引用次数: 0

Conserved polypeptides of Plasmodium falciparum as malaria vaccine candidates? 恶性疟原虫保守多肽作为疟疾候选疫苗?

Acta Leidensia Pub Date : 1991-01-01

S Herrera, M A Herrera, C Clavijo, A Corredor, U Certa

引用次数: 0

The pfmdr gene homologues of Plasmodium falciparum. 恶性疟原虫pfmdr基因同源物。

Acta Leidensia Pub Date : 1991-01-01

A F Cowman, S R Karcz

引用次数: 0

Is Plasmodium falciparum aldolase useful for rational drug design? 恶性疟原虫醛缩酶对合理的药物设计有用吗?

Acta Leidensia Pub Date : 1991-01-01

H Döbeli, C Itin, B Meier, U Certa

{"title":"Is Plasmodium falciparum aldolase useful for rational drug design?","authors":"H Döbeli, C Itin, B Meier, U Certa","doi":"","DOIUrl":"","url":null,"abstract":"P. falciparum lacks a functional citric acid cycle. Unlike most tissues of the mammalian host, it is totally dependent on glycolysis for energy generation. A compound which selectively inhibits the parasite's ATP-generating machinery is therefore a potential antimalarial agent. Such a drug may interact in two ways: a) by inhibiting the activity of an enzyme or b) by disturbing the micro-organization of consecutive enzymes in a metabolic pathway. In mammalian tissues the glycolytic pathway involves the cytoskeleton as a matrix to keep phosphofructokinase, aldolase and glyceraldehyde-3-phosphate dehydrogenase in an optimal sterical position for rapid substrate conversion. For instance, these three enzymes bind to the band 3 protein in erythrocytes or to actin in muscle cells. P. falciparum aldolase binds with very high affinity to the band 3 protein of human erythrocyte ghosts. However, the true in vivo site of association is believed to be actin II of P. falciparum. This actin has a sequence element which is almost identical to that of the band 3 aldolase binding site. We therefore suppose that plasmodia exploit a similar matrix organization. If true, the association of these enzymes with the cytoskeleton is a target for novel antimalarials. In contrast to all vertebrate aldolases, P. falciparum and P. berghei aldolases have two neighbouring lysine residues near the carboxy-terminus. We show here that mutagenesis of these basic residues has an effect on the catalytic constants Vmax and KM and moreover, the ability to bind to band 3 is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)","PeriodicalId":7108,"journal":{"name":"Acta Leidensia","volume":"60 1","pages":"135-40"},"PeriodicalIF":0.0,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12983771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0