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541.
Seringe E Thellier M Fontanet A Legros F Bouchaud O Ancelle T Kendjo E Houze S Le Bras J Danis M Durand R;French National Reference Center for Imported Malaria Study Group 《Emerging infectious diseases》2011,17(5):807-813
Little is known about severe imported Plasmodium falciparum malaria in industrialized countries where the disease is not endemic because most studies have been case reports or have included <200 patients. To identify factors independently associated with the severity of P. falciparum, we conducted a retrospective study using surveillance data obtained from 21,888 P. falciparum patients in France during 1996-2003; 832 were classified as having severe malaria. The global case-fatality rate was 0.4% and the rate of severe malaria was ≈3.8%. Factors independently associated with severe imported P. falciparum malaria were older age, European origin, travel to eastern Africa, absence of chemoprophylaxis, initial visit to a general practitioner, time to diagnosis of 4 to 12 days, and diagnosis during the fall-winter season. Pretravel advice should take into account these factors and promote the use of antimalarial chemoprophylaxis for every traveler, with a particular focus on nonimmune travelers and elderly persons. 相似文献
542.
F Kheirandish MJ Tarahi A Haghighi E Nazemalhosseini- Mojarad M Kheirandish 《Iranian Journal of Parasitology》2011,6(4):76-83
Background
Food contamination may occur through production, processing, distribution and preparation. In Iran especially in Khorramabad, 33° 29'' 16" North, 48° 21'' 21" East, due to kind of nutrition, culture and economic status of people, bread is a part of the main meal and the consumption of bread is high. In this study, the bakery workers were studied for determining of intestinal parasites prevalence.Methods
The study was carried out during September to November 2010 in Khorramabad. All the 278 bakeries and the bakery workers including 816 people were studied in a census method and their feces were examined for the presence of parasites by direct wet-mount, Lugol''s iodine solution, and formaldehyde-ether sedimentation, trichrome staining, and single round PCR (For discrimination of Entamoeba spp).Results
Ninety-six (11.9%) stool specimens were positive for different intestinal parasites. Intestinal parasites included Giardia lamblia 3.7%, Entamoeba coli 5.5%, Blastocystis sp. 2.1%, Entamoeba dispar 0.4%, Hymenolepis nana 0.1%, and Blastocystis sp. 0.1%.Conclusion
In order to reduce the contamination in these persons, some cases such as stool exam every three months with concentration methods, supervision and application of accurate health rules by health experts, training in transmission of parasites are recommended. 相似文献543.
形态学教学为人体寄生虫学教学的重要基础?目前,医学院校形态学教学中存在标本短缺?形态不典型,青年教师寄生虫虫种虫期形态上鉴别能力不足等问题?寄生虫教学资源平台建设由于寄生虫病的流行特点而存在不足,缺乏科学规范的整合标准和现代信息与网络技术支撑,不能形成具有综合集成?优化配置?最大限度发挥资源的效益?中国寄生虫种质资源平台的建立可以实现共享的信息量大?规范的教学资源,为寄生虫学形态学教学?青年教师培养?开放性学习提供了基础? 相似文献
544.
Bolhassani A Zahedifard F 《International journal of cancer. Journal international du cancer》2012,131(8):1733-1743
The design of efficient cancer treatments is one of the major challenges of medical science. Therapeutic vaccines of cancer have been emerged as an attractive approach for their capacity of breaking the immune tolerance and invoking long-term immune response targeting cancer cells without autoimmunity. An efficient antigen delivery system is the key issue of developing an effective cancer vaccine. In this regard, live vaccination strategies including various live bacterial and viral vectors have attracted a great attention. Several bacterial strains such as Salmonella, Listeria monocytogenes and Lactococcus lactis effectively colonize solid tumors and act as antitumor therapeutics. On the other hand, the use of viruses as vaccine vectors such as Vaccinia, Adenovirus, Herpes simplex virus, Paramyxovirus and Retroviruses utilizes mechanisms that evolved in these microbes for entering cells and capturing the cellular machinery to express viral proteins. Viral/bacterial-vectored vaccines induce systemic T-cell responses including polyfunctional cytokine-secreting CD4+ and CD8+ T-cells. However, there is an urgent need for the development of new safe live vaccine vectors that are capable of enhancing antigen presentation and eliciting potent immune responses without the risk of development of disease in humans. Recently, nonpathogenic parasites including Leishmania tarentolae, Toxoplasma gondii and Trypanosoma cruzi have emerged to be a novel candidate for gene delivery and heterologous genes expression. In this review, recent researches on cancer therapy using genetically modified bacteria and virus are summarized. In addition, live parasite-based vectors will be discussed as a novel anticancer therapeutic approach. 相似文献
545.
Objectives:
The aim of this work is to determine the prevalence of intestinal parasites and bacteria among the food handlers.Materials and Methods:
Two hundred food-handlers were subjected to a cross-sectional study working in the kitchen of a tertiary care hospital, i.e., Alnoor Specialist Hospital, Makkah, Saudi Arabia from February 2 to 27, 2009. The stool samples were examined for intestinal parasites following direct microscopic examination, formol ether concentration (Ritchie), and staining with modified acid fast staining techniques. For enteropathogenic bacteria samples were inoculated onto MacConkey''s agar, deoxycholate citrate agar, xylose lysine deoxycholate agar as per the World Health Organization protocol. Fingernail materials were examined microscopically for enteropathogenic bacteria and parasites.Results:
The majority (80%) of the food-handlers were young adults aged from 22 to 42 years. No intestinal parasites were detected from fingernail contents. Forty six (23%) stool specimens were positive for intestinal para¬sites. Giardia lamblia 18 (9%) was most frequent among the 10 different types of detected intestinal parasites followed by Entamoeba histolytica 9 (4.5%). No pathogenic bacteria were detected in all stool samples, whereas finger nails showed isolation of microorganisms as coagulase-negative staphylococci 79 (39.5%), followed by Staphylococcus aureus 35 (17.5%).Conclusion:
The findings emphasized the importance of food handlers as potential sources of infections and suggested health institutions for appropriate hygienic and sanitary control measures. 相似文献546.
Ethnopharmacological relevance
Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils.Aim of the review
To provide a comprehensive overview of the ethnobotany, phytochemistry and biological activity of H. procumbens and possibly make recommendations for further research.Materials and methods
Peer-reviewed articles on H. procumbens were acquired on Scopus, ScienceDirect and SciFinder, there was no specific timeline set for the search. A focus group discussion was held with different communities in Botswana to further understand ethnobotanical uses of the plant.Results
Harpogophytum procumbens is used for a wide variety of health conditions in the form of infusions, decoctions, tinctures, powders and extracts. In addition to the common local use for arthritis and pain, other ethnomedicinal uses include dyspepsia, fever, blood diseases, urinary tract infections, postpartum pain, sprains, sores, ulcers and boils. Scientific studies revealed that H. procumbens exhibits analgesic, anti-oxidant, anti-diabetic, anti-epileptic, antimicrobial and antimalarial activities amongst others. Iridoid glycosides and phenylpropanoid glycosides have been the focus of phytochemical investigations as the biological activity has been ascribed to the iridoid glycosides (such as harpagoside and harpagide), which are common in nature and are known to possess anti-inflammatory activity. In addition, it has been shown that the hydrolysed products of harpagoside and harpagide have more pronounced anti-inflammatory activity when compared to the unhydrolysed compounds. Harpagophytum zeyheri is a close taxonomic ally of H. procumbens but H. procumbens is the favoured species of commerce, and contains higher levels of the pharmacologically active constituents. The two are used interchangeably and H. procumbens raw material is often intentionally adulterated with H. zeyheri and this may impact on the efficacy of inadequately controlled health products. The main exporter of this highly commercialised plant is Namibia. In 2009 alone, Harpagophytum exports were worth approximately €1.06 million. The high demand for health products based on this plant has led to over-harvesting, raising concerns about sustainability. Although only the secondary tubers are utilised commercially, the whole plant is often destroyed during harvesting.Conclusions
Harpagophytum procumbens is used to treat a wide range of ailments. Some of the ethnobotanical claims have been confirmed through in vitro studies, however, when the constituents deemed to be the biologically active compounds were isolated the efficacy was lower than that of the whole extract. This necessitates the use of a different approach where all the metabolites are considered using a robust method such as spectroscopy; the phytochemical data can then be superimposed on the biological activity. Furthermore, there is a need to develop rapid and efficient quality control methods for both raw materials and products because the orthodox methods in current use are time-consuming and labour intensive. 相似文献547.
Jason Lei 《Biochemical pharmacology》2010,79(7):1062-1071
In vitro cultures of two nematodes (Caenorhabditis elegans and Ascaris suum) were established to study the nematicidal activity of three monoterpenoids (thymol, carvacrol and p-cymene). Toxicity of thymol and carvacrol was found for the two nematodes tested. The study was then aimed to address whether nematode tyramine receptor (TyrR) could interact with the two compounds by using HEK293 mammalian cells transfected with a C. elegans TyrR (ser-2) sequence, in hope of developing a high-throughput cell-based platform for future screening of new antihelminthic compounds. SER-2 expression and functionality in the transfected cells was first confirmed by green fluorescent protein tagging, competitive receptor binding, intracellular cyclic AMP, and intracellular calcium [Ca2+]i mobilization assays. Thymol and carvacrol were then tested and demonstrated to interact with TyrR in desensitizing SER-2 for tyramine activation in [Ca2+]i mobilization assay, and in translocating SER-2 from membrane to cytoplasm in receptor internalization assay. Receptor internalization activity of thymol and carvacrol was significantly blocked in cells expressing mutant SER-2 with the S210A/S214A double mutations, thus confirming specificity of the interactions. In summary, the current study showed that the nematicidal activity of thymol and carvacrol might be mediated through TyrR as the two compounds could trigger the signaling cascade downstream from the receptor in cells expressing wild-type but not a mutant SER-2. The TyrR-expressing cell system may prove to be a good screening platform for developing new antihelmintic compounds that may overcome parasite drug resistance, especially when such chemicals are used in combination with commercial drugs. 相似文献
548.
目的对江阴市农田土壤中重金属铅、镉及寄生卵的污染进行调查,为客观评价农村土壤卫生状况提供科学依据。方法对江阴市的15个镇(街道)的60个行政村的农田土壤进行采样分析。结果以国家《土壤环境质量标准》(GB 15618-1995)二级标准作为评价标准,只有一个土样中镉含量超过国家标准限值,达标准限值的1.10倍,为轻度污染,其余土样均在国家二级标准的限值范围内。以当地的背景值作为评价依据,有63.33%的铅和31.67%的镉均超过背景值;11.67%的农田土壤中检出活的寄生虫卵。结论江阴市农田土壤总体受到轻度重金属污染,应当加强管理和防范工作。 相似文献
549.
550.
《Expert review of anti-infective therapy》2013,11(6):867-885
Following the discovery of innate immune receptors, the topics of innate immunity and its role in defense against infective agents have recently blossomed into very active research fields, after several decades of neglect. Among innate immune cells, natural killer (NK) cells are endowed with the unique ability to recognize and kill cells infected with a variety of pathogens, irrespective of prior sensitization to these microbes. NK cells have a number of other functions, including cytokine production and immunoregulatory activities. Major advances have recently been made in the understanding of the role of NK cells in the physiopathology of infectious diseases. The cellular and molecular mechanisms regulating the acquisition of effector functions by NK cells and their triggering upon pathogenic encounters are being unraveled. The possibility that the power of NK cells could be harnessed for the design of innovative treatments against infections is a major incentive for biologists to further explore NK cell subset complexity and to identify the ligands that activate NK cell receptors. 相似文献