Annals of Tropical Medicine & Parasitology最新文献

{"title":"Molecular markers for chloroquine-resistant Plasmodium falciparum malaria in Thailand and Laos","authors":"Annie-Claude Labbé, P. Bualombai, Dylan R. Pillai, K. Zhong, V. Vanisaveth, B. Hongvanthong, S. Looareesuwan, Kevin C. Kain","doi":"10.1080/00034983.2001.11813697","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813697","url":null,"abstract":"Chloroquine-resistant Plasmodium falciparum is well documented in Thailand. Laos, however, continues to use chloroquine (CQ) as the first-line therapy for the treatment of P. falciparum malaria. The objective of the present study was to determine the prevalence, in these two areas, of the cg2, pfmdrl and pfcrt allelic types that have previously been associated with CQ_resistance. Isolates of P. falciparum were collected from participants in ongoing treatment studies conducted in Thailand (near the Thai-Cambodian border) and in Laos (Vang Vieng district). The pfmdrl and pfcrt alleles were characterized by PCR-RFLP and mutations in cg2 were characterized by PCR and single-stranded-conformation-polymorphism (SSCP) electrophoresis. Eight (32%) of the 25 Laotian isolates but only one (4%) of the 25 Thai isolates were found to contain the pfmdr1 mutation N86Y (P = 0.02). In contrast, the cg2 polymorphisms previously associated with CQ resistance were present in only 10 of the isolates from Laos but 24 of those from Thailand (40% v. 96%; P < 0.001). All the samples from both countries contained the pfcrt K76T mutant allele reported to confer resistance to CQ. The results may indicate that drug pressure for the maintenance of the pfmdrl and cg2 alleles varies in intensity in the Thai and Laotian study areas, probably reflecting differences in the national malaria-treatment policies of Thailand and Laos.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86681602","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}

{"title":"Subconjunctival zoonotic Onchocerca in an Albanian man","authors":"S. Pampiglione, N. Vakalis, A. Lyssimachou, G. Kouppari, T. C. Orihel","doi":"10.1080/00034983.2001.11813702","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813702","url":null,"abstract":"A case of subconjunctival infection with a zoonotic species of Onchocerca is described, in a 16-year-old Albanian man who had immigrated to Greece. This is the first report of human infection with Onchocerca in this tissue location and only the eighth report of zoonotic Onchocerca in man.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75423626","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}

{"title":"Trypanosoma brucei infection induces apoptosis and up-regulates neuroleukin expression in the cerebellum","authors":"J. Stiles, J. Meade, Z. Kučerová, D. Lyn, W. Thompson, Z. Zakeri, J. Whittaker","doi":"10.1080/00034983.2001.11813699","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813699","url":null,"abstract":"Human infection with Trypanosoma brucei may result in meningo-encephalitis, neuronal demyelination, blood-brain-barrier dysfunction, peri-vascular infiltration, astrocytosis and neuronal apoptosis. Prevention of the short- or long-term, parasite-induced, neuronal assault requires a better understanding of the host's responses to the infection at the molecular level. Northern analysis, cDNA micro-arrays, reverse-transcrip-tase-PCR (RT-PCR), SDS-PAGE and immunohistology were therefore used to investigate global gene and protein expression in the brains of mice infected with T. brucei. Temporal and spatial expression of neuroleukin (NLK), a predominant neurotrophin which is associated with neuronal protection and regeneration during neuronal assault in the brain, was then assessed. Expression of 20 of the 588 genes investigated (representing pro- and anti-inflammatory immuno-modulators, growth factors, neurotransmitters, and pro- and anti-apoptosis factors) was significantly altered (P < 0.05). TUNEL analysis revealed extensive apoptosis at peak parasitaemia, mainly in the cerebellum. RT-PCR analysis of two regulators of apoptosis, Bcl-x(L) (anti-apoptotic) and Bax (pro-apoptotic), revealed equivalent increases in levels of expression. NLK expression was up-regulated in punctated fashion in brain and was mainly localized to abnormal (stellate) catecholamine neurons (CN) in the locus coeruleus (LC) of infected [and, to a lesser degree, the normal (polygonal) cells of uninfected] brainstem. Expression of NLK receptor (NLK-R) was inversely correlated with that of NLK. At peak parasitaemia, trypanosome infection apparently induces cerebellar apoptosis and a corresponding increase in NLK expression. NLK may be modulating inflammation and is probably involved in protecting CN and the cerebellum against apoptosis.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74518790","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}

{"title":"Therapeutic efficacy of chloroquine against uncomplicated, Plasmodium falciparum malaria in south-western Saudi Arabia","authors":"H. Ghalib, S. Al-ghamdi, M. Akood, A. Haridi, A. A. Ageel, R. E. Abdalla","doi":"10.1080/00034983.2001.11813696","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813696","url":null,"abstract":"The results of annual random screening indicated that Plasmodium falciparum strains showing chloroquine (CQ) resistance in vitro became increasingly common in the Jazan region of south-western Saudi Arabia between 1986 and 1998 (χ2 for trend = 50.027; P < 0.001). This worrying trend and the emergence of a micro-epidemic in 1997–1998 prompted an assessment of the therapeutic efficacy of CQ against uncomplicated, P. falciparum malaria in the area. The in-vivo testing of sensitivity to CQ was carried out in 291 clinically manifest, microscopically positive cases of P. falciparum malaria. Most of these patients (88%) were successfully treated with a single standard regimen of CQ therapy. The other 36 patients (12%) showed early treatment failure or a poor response to the CQ, although all of these were then successfully treated with a single standard dose of sulfadoxine-pyrimethamine (Fansidar), as a replacement therapy. Those unsuccessfully treated with CQ were generally younger (t = 2.625; P = 0.01) and tended to have higher body temperatures (t= -2.62; P= 0.012) and higher levels of parasitaemia at initial presentation (P> 0.000) than those who responded well to the drug. Although CQ remains a reasonably effective drug for the treatment of malaria in the Jazan region, and therefore will be kept as the first-line drug for the foreseeable future, failure of CQ efficacy must be carefully monitored in the area.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74218089","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}

{"title":"Cuticular-hydrocarbon discrimination between Anopheles gambiae s.s. and An. arabiensis larval karyotypes","authors":"G. Anyanwu, D. Davies, D. Molyneux, A. Priestman","doi":"10.1080/00034983.2001.11813704","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813704","url":null,"abstract":"Examination of chromatograms of karyotyped larvae of Anopheles gambiae s.s. and Anopheles arabiensis has revealed that there are differences in the profile of their epicuticular hydrocarbons. A discriminant analysis of the quantitative hydrocarbon data has shown that the An. gambiae Mopti 2Rbc/bc karyotype from Mali could be separated from the Forest 2La/a karyotype from Liberia in >80% of cases. Similar analysis permitted > 80% separation of individuals of two karyotypes of Anopheles arabiensis: 2Rab/ + from Burkina Faso, and 2Rb/b from Madagascar.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75204526","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}

{"title":"A rapid-cooling method for cryopreserving Entamoeba histolytica","authors":"N. Samarawickrema, J. Upcroft, N. Thammapalerd, P. Upcroft","doi":"10.1080/00034983.2001.11813705","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813705","url":null,"abstract":"Entamoeba histolytica, the causative agent of human amoebiasis, is a very difficult organism to culture and cryopreserve (Mirelman, 1992; Spice and Ackers, 1992; Diamond, 1995). Several cooling techniques to preserve E. histolytica, involving a range of rapid to slow (Diamond, 1964) and uncontrolled Games, 1988) cooling procedures using cryoprotectants, have been described. As cryopreservation is dependent on several factors, including the rapidity of cooling, the presence of cryoprotectants and serum proteins, bacterial associates and minor variations in the membrane components of E. histolytica strains, the success of these methods varies. When used at the Q!.teensland Institute of Medical Research (QIMR) in Brisbane, several of the more established methods, including step-wise, slow cooling-at 1°C/min from 0°C to 25°C and then at 5°C/min to 196°C (Phillips et al., 1984) or at 1 °C/min from room temperature to 100°C (Diamond, 1964; Farri et al., 1983) or at 1 °C/min from 37°C to 60°C followed by immersion in liquid nitrogen Games, 1988)-and uncontrolled fast cooling-to 25°C in a methanol bath followed by subsequent immersion in liquid nitrogen Games, 1988) or direct transfer to -70°Conly yielded viable parasites on thawing when xenic (not axenic) strains of E. histolytica were used (unpubl. obs.). The simple method of preserving E. histolytica described below, involving a high concentration of serum and an uncontrolled cooling rate, consistently gave a good recovery of the trophozoites of an axenic strain of E. histolytica on thawing. The strain used, HTH-56:MUTM, was originally isolated from a liver abscess (Thammapalerd et al., 1993). Parasite cultures containing approximately 3.0 X 105 parasites/10-m! culture tube were chilled, 72 h after they had been sub-cultured, in an ice bath for 5 min and then centrifuged at 120 X g for 5 min. The supernatant solution was decanted off and the parasite pellet resuspended in 0.5 ml TYI-S-33 medium (Diamond et al., 1978) supplemented with 0%, 10%, 20%, 50%, 60% or 75% heat-inactivated horse serum (Gibco BRL, Rockville, MD). The parasite suspension was then transferred to a Nunclon® cryotube (Nalge Nunc International, Rochester, NY) containing 0.5 ml of a cryoprotectant solution [15% dimethylsulphoxide (DMSO; Sigma) prepared in TYI-S-33 containing the same concentration of horse serum as used to resuspend the parasites] such that the total volume of suspension in each cryotube was 1.0 ml. The parasites were incubated at 37°C for 15 min, to allow them to take up the DMSO (Farri et al., 1983), and then subjected to rapid cooling by transferring the cryotubes directly into a bath of liquid isopropanol (of analytical grade) pre-chilled to 70°C. The isopropanol bath was in turn placed in a freezer at 70°C for 48 h and then the cryotubes were transferred directly into the liquid phase of liquid nitrogen (at 196°C) for storage for a minimum period of 7 days. Routinely, five replicate vials were processed at a tim","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79187106","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}

{"title":"Misidentification of Onchocerca volvulus as guinea worm","authors":"M. Eberhard, G. Melemoko, A. Zee, M. Weisskopf, E. Ruiz-Tiben","doi":"10.1080/00034983.2001.11813701","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813701","url":null,"abstract":"Over the past 10 years, the status of human infection with guinea worm (Dracunculus medinensis) in the Central African Republic (CAR) has been difficult to ascertain. It is unclear if indigenous cases are occurring and whether cases are migrating into the CAR from surrounding countries. A team of investigators visited the CAR in July-August 2000, to attempt to ascertain the presence of indigenous transmission. No cases of true guinea-worm infection (i.e. dracunculiasis) were detected, but three cases of human infection with Onchocerca volvulus, each of which had been misidentified as dracunculiasis, were detected. The unusual presentation of skin blisters and extraction of an intact female O. volvulus are described. As a result of this investigation, and the confusion of onchocerciasis being misidentified as dracunculiasis, the presence of endemic transmission of guinea worm in the CAR remains in question.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89551454","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}

{"title":"R. C. Muirhead-Thomson","authors":"M. Service","doi":"10.1080/00034983.2001.11813706","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813706","url":null,"abstract":"Regretfully-because his wife, Catherine, predeceased him and he had no children and left no other close relatives-the death on 4 October 2000 of Robert Charles Muirhead-Thomson, a world renowned medical entomologist, has only just come to my attention. Muirhead-Thomson was born in Kilmaurs, Scotland, on 2 May 1914. He entered Glasgow University to study Zoology, obtaining his B.Sc. in 1936 and D.Sc. in 1942. (His time as an undergraduate overlapped that of D. S. Bertram and W. H. R. Lumsden.) In 1937, after his first degree, he obtained a Royal-Society grant and conducted research on mosquitoes at the London School of Hygiene and Tropical Medicine. This prepared him for his detailed investigations in the early 1940s on the behaviour of malaria vectors, especially on Anopheles minimus, in Assam, India. These studies were supported in part by another Royal-Society grant and in part by funding from the Colonial Medical Research Service. The latter continued to finance his research from the mid-1940s to early 1950s, in Ghana, Sierra Leone, Nigeria and Tanzania, on the biology of malaria vectors, in particular An. gambiae and An. melas. From 1955-1957, with funding from the U.S. National Institutes of Health, Muirhead-Thomson worked on malaria epide~ology in Liberia. For the following 9 years he worked for the World Health Organization, in India and Zimbabwe as well as at their headquarters in Geneva. He then returned briefly to the London School of Hygiene and Tropical Medicine. Although mainly known for his studies on anopheline biology in India and West Africa, he also worked on mosquito behaviour in South Africa, Jamaica and Trinidad. In 1956 he published results of his studies on the transnuss10n, by mosquitoes as well as by fleas, of myxomatosis in England. He thus had experience of mosquito biology in four continents. In 1966, Muirhead-Thomson's career changed direction and he began investigating the effects of insecticides on the larvae of simuliid blackflies, at the then University of Rhodesia. He then returned and settled· in England. With funding from the Leverhulme Foundation and the Medical Research Council, he went firstly to Reading University and then to Royal Holloway College, London University, where he studied the impact pesticides had on simuliids and other aquatic macro-invertebrates. Muirhead-Thomson published about 54 pa· pers, many of which were long and accompanied by his photographs (he was an enthusiastic photographer). His first, on myiasis in sheep in south-western Scotland and· co-authored by A. J. Haddow, was published in 1937 in Parasitology. In his last article, which appeared in 1998 in the Annals of Tropical Medicine and Parasitology (92, 891-893), he vigorously argued that xenodiagnosis of malaria cases had many advantages over taking blood films. Not many of us can claim publications spanning 61 years! In addition to scientific papers, MuirheadThomson wrote seven books (1948-1991). The first was entitled Assam Vall","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89883591","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}

{"title":"Malaria epidemiology and control in refugee camps and complex emergencies","authors":"M. Rowland, F. Nosten","doi":"10.1080/00034983.2001.11813694","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813694","url":null,"abstract":"Owing to the breakdown of health systems, mass population displacements, and resettlement of vulnerable refugees in camps or locations prone to vector breeding, malaria is often a major health problem during war and the aftermath of war. During the initial acute phase of the emergency, before health services become properly established, mortality rates may rise to alarming levels. Establishing good case management and effective malaria prevention are important priorities for international agencies responsible for emergency health services. The operational strategies and control methods used in peacetime must be adapted to emergency conditions, and should be regularly re-assessed as social, political and epidemiological conditions evolve. During the last decade, research on malaria in refugee camps on the Pakistan-Afghanistan and Thailand-Burma borders has led to new methods and strategies for malaria prevention and case management, and these are now being taken up by international health agencies. This experience has shown that integration of research within control programmes is an efficient and dynamic mode of working that can lead to innovation and hopefully sustainable malaria control. United Nations' humanitarian and non-governmental agencies can play a significant part in resolving the outstanding research issues in malaria control.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80436106","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}

{"title":"Evaluation of a PCR-ELISA to detect Wuchereria bancrofti in Culex pipiens from an Egyptian village with a low prevalence of filariasis","authors":"Ibrahim H. Kamal, Peter U. Fischer, M. Adly, A. S. E. Sayed, Z. S. Morsy, Reda M. R. Ramzy","doi":"10.1080/00034983.2001.11813703","DOIUrl":"https://doi.org/10.1080/00034983.2001.11813703","url":null,"abstract":"The programmes for the elimination of bancroftian filariasis that have been implemented in the Nile delta of Egypt are expected to lead to substantial reductions in filarial loads in the treated populations. Better methods than those currently available are needed for monitoring the efficacy of these and similar efforts at intervention. A PCR-ELISA was therefore evaluated as an epidemiological tool for the detection of the Wuchereria-bancrofti-specific SspI repeat in pools of Culex pipiens collected in a village with a low prevalence of filarial infection in its human residents (2.1%). Indoor-resting mosquitoes were collected by aspiration from 114 randomly selected houses (during one to nine visits/house) and separated into 673 pools, each of which held the mosquitoes collected during one night from one house. Although 18 (2.7%) of the pools showed PCR inhibition and had to be excluded, filarial DNA was detected, using the PCR-ELISA, in 91 (13.9%) of the 655 remaining mosquito pools. The minimum prevalence of W. bancrofti infection in the mosquitoes caught (assuming one infected mosquito/positive pool) was 2.8%. The mean (s.d.) number of mosquitoes/pool did not vary significantly between positive [5.5 (3.4)] and negative [4.9 (3.5)] pools. The assay detected parasite DNA in mosquitoes from 19.3% of 114 houses when only the first visit was considered and from 73.9% of the 88 houses visited more than once. The PCR-ELISA yielded results comparable with those of the regular PCR-SspI assay. The latter assay is recommended for the routine examination, in laboratories in endemic areas, of mosquito pools from randomly selected houses, as the ELISA component of the PCR-ELISA is exceedingly time-consuming, expensive and requires special equipment.","PeriodicalId":8038,"journal":{"name":"Annals of Tropical Medicine & Parasitology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75147881","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}