兴宁市人体肠道寄生虫感染现状调查

目的了解和分析兴宁市人体肠道寄生虫感染现状与防治效果。方法采用改良加藤涂片法检查肠道寄生虫卵;采用试管滤纸培养法检查钩虫;用肛门透明胶纸拭擦法检查蛲虫卵。结果共调查1663人,查出肠道寄生虫4种,有200人感染,总感染率为12.03％,其中感染钩虫、蛔虫、鞭虫和蛲虫者分别为38人、117人、45人和87人;感染率分别为2.28％、7.03％、2.70％和23.84％。男女感染率为11.74％和12.29％,差异无统计学意义(x2:0.12,P>0.05);小于7岁儿童总感染率为11.76％,7～14岁学生总感染率为15.82％,大于14岁的人群总感染率为10.17％,差异有统计学意义(X2=9.91,P<0.01);不同镇的感染率,差异有统计学意义(X2=23.81,P<0.01);结论肠道寄生虫感染与生活居住环境、卫生条件、生活习惯等因素有关。广泛宣传教育,增强人们的卫生意识,提高自我保健能力是控制或消除人体肠道寄生虫感染的有效措施。     

Periodate treatment of Anisakis simplex allergens

Moneo I, Audicana MT, Alday E, Curiel G, del Pozo MD, García M. Periodate treatment of Anisakis simplex allergens.
Anaphylactic reactions after parasitized fish consumption are mediated by an IgE response. However, positive skin tests and specific IgE can also be found in many asymptomatic subjects who recognize a single medium mol.-wt. antigen by IgE immunoblot. The study aimed to find out whether this unspecificity was due to the carbohydrate moieties of parasite antigens. Sixty-two patients with suspected parasite allergy, 51 blood donors, 18 bakers, and 38 atopic patients were studied by blotting. Parasite proteins were treated with periodate. Several selected sera were inhibited with a crude wheat extract and fungal amylase. Twelve patients '19%', eight donors '16%', six bakers '33%', and one atopic patient '3%' recognized a single mediummol.-wt. band in blotting and should be considered false-positive. This band was periodate-sensitive, but specific IgE to this allergen could not be inhibited by a wheat extract nor by fungal amylase and was clinically irrelevant. Diagnosis of Anisakis simplex hypersensitivity by skin tests and/ or specific IgE values should always be confirmed by specific IgE immunoblotting in order to detect the presence of clinically unrelated antibodies directed to periodate-sensitive allergens. These allergens are probably not a carbohydrate moiety of a parasite glycoprotein.     

The role of low level Plasmodium falciparum parasitaemia in anaemia among infants living in an area of intense and perennial transmission

Summary Children under one year of age in an area of intense and perennial Plasmodium falciparum transmission were followed up for one year to establish to what extent chronic, low parasitaemia was associated with severe anaemia. There was a significant increase in the prevalence of anaemia (PCV ≥ 25%) with increase in parasite density. PCV levels were related not only to concurrent parasite density but also decreased with densities measured one month previously. At any point in time, the mean PCV level in infants with low parasitaemia (<1000 parasites/μ1) was higher than that of infants with intermediate (1000–9999/μ1) and high parasite densities (≥10 000/μl). After the age of 7 months, infants with low parasite densities tend to recover, probably as a result of developing immunity. At the age of 12 months, they have similar PCV levels to infants with no detectable parasitaemia by microscopy. The maintenance of low parasite density appears crucial to the survival of infants in malaria endemic areas. The findings suggest that interventions which lower parasite densities in areas of intense transmission reduce the development of severe malarial anaemia and thus malaria-related mortality and morbidity in infants.     

Evolution and immunity

This report describes a meeting organized by Ken Smith and Jim Kaufman, entitled Evolution and Immunity, which took place at the University of Cambridge on 24 September 2009 to honour the anniversaries of the birth of Darwin and the first publication of The Origin of Species. Ten internationally‐known speakers described the effects of evolution on immunity, ranging in timescales from the deep‐time evolution of adaptive immune systems in vertebrates and invertebrates to the evolution of pathogens and lymphocytes within a single individual. The final talk explored the application of phylogenetic analysis to non‐biological systems.     

A perspective on periodontal diagnosis

Periodontal diseases are best considered as the outcome of an imperfect host-parasite interaction. In most cases, diagnosis involves labelling certain clinical manifestations without a complete understanding of the causes of the disease. Therefore, treatment based on the "diagnosis" is not necessarily logical or effective. As the causes which underly the disease become more evident, the underlying mechanisms of disease can be used to refine our diagnostic methods. For example, deficiencies in host defenses, or the presence or increased proportions of certain bacterial pathogens may be indicative of imbalances in the normal host-parasite equilibrium. For a laboratory test to be reliably applied to the diagnosis of a clinical condition, it is essential that an absolute criterion of the clinical disease first be established. Then the sensitivity and the specificity of the test can be determined using appropriate experimental designs. The demonstration of a good correlation between a test outcome and a clinical condition is, of itself, insufficient grounds to use the test for diagnostic purposes.     

甘草甜素治疗慢性乙型肝炎疗效观察

甘草甜素治疗慢性乙型肝炎疗效观察宋星宏自１９９１～１９９６年，我们用甘草甜素配合其他保肝药物治疗慢性乙型肝炎５６例，并与单用保肝药治疗的４７例作对照观察，现将结果总结如下。临床资料全部病例符合１９９５年第五次全国传染病寄生虫病学术会议讨论修定的病毒性...     

Molecular biology of rickettsiae

Our understanding of the biology of the rickettsiae, organisms that are the archetype of the obligate intracytoplasmic bacterial parasites, remains muddy and fragmentary. For example although we all appreciate that the rickettsiae can exploit their unique environment, the host cell cytoplasm, but are unable to grow axenically, the basis of this fact is still one of microbiology's central mysteries. It is unfortunate, but true, that because of the inherent difficulty of working within this system, progress on the answers to such questions will be slow and laborious. However, with the application of molecular biological methods, that is, the powerful modern approaches of genetics and biochemistry, the rickettsiology community has the realistic prospect that this field is far from being at a stand-still and that significant increases in our comprehension of the fundamental problems of rickettsial biology are occurring and will continue to occur at ever accelerating rates. Some examples, both in terms of scientific conclusions and technical approaches, of the progress made in recent years and expectations for the near future will be presented.Presented at the 4th International Symposium on Rickettsiae and Rickettsial Diseases, Pietany, C.S.F.R., 1–6 October, 1990.     

大理市凤仪镇肠道寄生虫感染调查

目的：了解农村肠道寄生虫病的流行状况。方法：粪便生理盐水直接涂片法,粪便涂片碘染液法。结果：调查 1012人,查出寄生虫感染 426人,人群感染率 42. 09％,共检出蛔虫、鞭虫、带绦虫、钩虫四种寄生虫感染。其中蛔虫感染率最高,达 40. 12％。其余虫种的感染率不超过 2％。学龄前儿童的感染率为 58. 25％,在校小学生的感染率为 47. 36％,成人感染率为 39. 24％,三者具有显著性差异。 (χ 2=305. 41 P<0 01)结 论 ： 调 查 结 果 表 明 蛔 虫 在 当 地 感 染 较 严 重 , 农 村 寄 生 虫 感 染 以 低 龄 儿 童 及 小 学 生 为 主 , 且 随 着 年 龄 的 增 长 , 感 染 率 呈 逐 渐 下 降 趋 势 。     

Of parasites and men

The living world has evolved and is evolving through interspecific relationships between organisms. The diversity of these interactions is enormous going from mutualism to parasitism. Humans live with a multitude of microorganisms, essential for their biology. However, interactions are not always advantageous. Indeed, many organisms might become pathogens, such as the Plasmodium species, the causative agents of malaria. Like many other microorganisms, they are «Machiavellian» in their capacity to elaborate a range of reproduction strategies, giving them a huge advantage in terms of adaptation. Here, we discuss the role played by parasites in the ecology and evolution of living organisms and particularly of humans. In the study of infectious diseases, humans are legitimately the focal point, although they represent only one ecosystem among many others and not taking this into account certainly biases our global view of the system. Indeed, we know only a minimal fraction of the microorganisms we live with. However, parasites have shaped and are still shaping the human genome. Several genetic signatures are the proofs of the selection pressures by parasites that humankind has endured during its evolution.But, ultimately, what are the solutions for living with pathogens? Should we eradicate them or should we learn how to control and manage them?     

Approaches to the identification of susceptibility genes

Although previous studies have revealed a great deal about the genetic basis of susceptibility and resistance to parasite infection, there is now an opportunity to considerably enhance understanding through genome-wide association mapping. The application of association mapping to complex inheritance has recently become achievable given reduced costs, sophisticated genotyping platforms and powerful statistical methods which build upon increased knowledge of the linkage disequilibrium structure of the human genome. Linkage mapping and related approaches remain useful for the localization of the rarer genetic variants and candidate region association studies can be a very cost-effective route to progress. However, genome-wide association offers the greatest promise, despite the challenges posed by phenotype complexity, ensuring genotype coverage/quality and robust statistical analysis. The available approaches for mapping genes underlying susceptibility are reviewed here, emphasizing their relative merits and drawbacks and highlighting specific software tools and resources that enable successful mapping.