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surface antigens of leishmania donovani promastigotes.surface antigen profiles of leishmania donovani promastigote isolates have been studied. surface patterns of brazilian and african isolates display remarkable similarities and are extremely simple, consisting of three major peptides of 65,000, 25,000, and 23,000 mol wt. surface iodination and biosynthetic labeling coupled to immunoprecipitation techniques revealed that a single major determinant of 65,000 mol wt is recognized in all strains by sera from kala-azar patients from both brazil and af ...19836854205
leishmania donovani infections in phlebotomine sandflies from the kala-azar focus at aba roba in ethiopia: dna probe compared with conventional detection methods. 19938369567
animal reservoirs of leishmaniasis in marigat, baringo district, kenya.a total of 1128 rodents belonging to seven genera were examined for leishmanial parasites over a period of sixteen months. parasites were isolated from 36 (12.5%) tatera robusta, 3 (0.5%) arvicanthis niloticus, and 2 (0.8%) mastomys natalensis. all isolates were characterised by isoenzyme analysis using nine enzymes. the enzymes examined were: malate dehydrogenase (mdh), phosphoglucomutase (pgm), glucose phosphate isomerase (gpi), isocitrate dehydrogenase (icd), nucleoside hydrolase (nh), glucos ...19968625862
experimental infection of domestic sheep with culture-derived leishmania donovani promastigotes.domestic sheep were intradermally inoculated with culture-derived stationary phase leishmania donovani promastigotes. sampling of site of inoculation, liver and spleen for 244 days showed that this parasite can stay alive in the skin for up to 28 days post-inoculation. apart from pyrexia that was evident in all the animals for 42 days, no other symptoms of kala-azar were seen. no parasites were recovered from the visceral organs throughout the sampling period, suggesting that sheep are not susce ...19989561716
identification of leishmania from mucosal leishmaniasis by recombinant dna probes.three cases of mucosal leishmaniasis are described. parasites isolated from mucosal lesions were identified by southern blot analysis of their genomic deoxyribonucleic acids (dnas) using recombinant dna probe pdk20. parasites from 2 patients were identified as leishmania donovani s.l. one of the patients had pure mucosal lesions, while in the second patient there was dissemination of the parasite to other organs. the spectrum of the disease caused by l. donovani is discussed. the parasite from t ...19921440775
a new focus of kala-azar due to leishmania donovani sensu lato in kenya.three masai children from kekonyokie south location, kajiado district were diagnosed with visceral leishmaniasis (kala-azar). leishmanial isolates from the patients were characterized as leishmania donovani sensu lato, by cellulose acetate electrophoresis. case histories indicated that the disease was acquired locally. a survey of 409 children at 7 local primary schools and one nursery school revealed no additional case. sandfly surveys using light traps and sticky paper traps recovered 10 speci ...19938337711
rk39 enzyme-linked immunosorbent assay for diagnosis of leishmania donovani infection.the rk39 enzyme-linked immunosorbent assay (elisa) was compared with the direct agglutination test (dat) for leishmania donovani infection in the sudan. rk39 elisa proved more sensitive than dat in diagnosis of kala-azar (93 and 80%, respectively); both tests may remain positive up to 24 months after treatment. for patients with post-kala-azar dermal leishmaniasis and individuals with subclinical infection, rk39 elisa performed as well as dat but could detect infection 6 months earlier in approx ...19989729541
phlebotomine sandflies associated with households of human visceral leishmaniasis cases in baringo district, kenya.a 12-month field study on sandflies was conducted from april 1992 to march 1993 at three locations in baringo district, rift valley province, kenya. study sites were selected based on their close proximity to the households of three patients who had had parasitologically confirmed visceral leishmaniasis in 1988, 1990 or 1991. sandfly populations were highest during the two rainy seasons, april-june and november-december. a significant association was detected between the monthly abundance of san ...19947893180
comparison of three culture media for isolating leishmania donovani from splenic aspirates in kenyan visceral leishmaniasis. 19846545198
visceral leishmaniasis in somalia. circulating antibodies as measured by dat, immunofluorescence and elisa.sera from patients with visceral leishmaniasis (vl) (n = 26), healthy residents of mogadishu (n = 157), inhabitants of a village in an endemic area (n = 276) and healthy swedes (n = 60) were examined using the direct agglutination test (dat), immunofluorescence (if) and elisa for antibodies against leishmania donovani. the study was carried out in order to provide baseline data for antibody responses in visceral leishmaniasis as existing in somalia and to explore which one of these methods would ...19958592766
comparative infectivity of a kenyan strain of leishmania donovani amastigotes for rattus rattus and the laboratory white rat.amastigotes of a kenyan strain of leishmania donovani from a previously infected hamster were used to inoculate rattus rattus and the laboratory white rat intracardially. the animals were sampled at 2, 4, 6, and 12 weeks post-inoculation to determine infectivity and total parasite burdens in the liver and spleen. higher parasite burdens were observed in the livers and spleens of r. rattus. parasite culture indicated more generalized parasite dissemination compared to the white rat. demonstration ...19872894131
evaluation of complement fixation procedures for the diagnosis of visceral leishmaniasis.three complement fixation (cf) procedures were evaluated for their ability to detect serum antibodies to visceral leishmaniasis. these tests differ in their use of buffers, volumes of complement and sensitized erythrocyte concentrations, incubation times and percentage haemolysis endpoints. freeze-thawed sonicates of leishmania donovani promastignotes were used as antigen. test sensitivity was determined using sera from 46 kenyans with parasitologically proven leishmaniasis. the frequencies of p ...19854096564
splenomegaly in baringo district, kenya, an area endemic for visceral leishmaniasis and malaria.the relationship between splenomegaly and visceral leishmaniasis (vl) was investigated during a cross-sectional study in 2,941 individuals in baringo district, kenya, where both malaria and vl are endemic. spleen size was correlated with presence of malaria parasites in thick blood films and with evidence of present or past leishmania donovani infection as determined by serology and history. marked splenomegaly (hackett grade 3 or greater) significantly correlated with present or previous leishm ...19957483000
indigenous human cutaneous leishmaniasis caused by leishmania tropica in kenya.six leishmania isolates from 3 indigenous kenyans (2 isolates from one patient) and 2 canadian visitors in kenya were characterized by cellulose acetate electrophoresis. the isolates were compared among themselves and with reference strains of leishmania donovani, l. aethiopica, l. major, l. tropica, and l. arabica using 9 enzymes: malate dehydrogenase (mdh), malic enzyme (me), phosphogluconate dehydrogenase (6pgd), glucose-6-phosphate dehydrogenase (g6pd), aspartate aminotransferase (asat), ade ...19883177740
concurrent infection with leishmania donovani and leishmania major in a kenyan patient: clinical description and parasite characterization.leishmania isolates aspirated a few months apart from the spleen of an indigenous adult male kala-azar patient from baringo district, kenya, were biochemically characterized and compared. the patient lived within a dual focus of l. donovani kalazar and l. major cutaneous leishmaniasis. a primary leishmania isolate from splenic aspirates was cryopreserved (nlb-294). the patient was treated with sodium stibogluconate for kala-azar and discharged. three months later, he had clinical relapse and ret ...19911928563
a killing disease epidemic among displaced sudanese population identified as visceral leishmaniasis.a fatal disease epidemic affected the bentiu area in southern sudan and led to a mass migration of the nuer tribe searching for treatment. the initially available information revealed a high mortality rate due to a possible occurrence of tuberculosis, malaria, enteric fever or visceral leishmaniasis (vl). serological screening of 53 of the most severely affected patients in an enzyme-linked immunosorbent assay (elisa) or an improved direct agglutination test (dat) revealed positivity for vl. in ...19911852133
identification of leishmania donovani using a polymerase chain reaction in patient and animal material obtained from an area of endemic kala-azar in the sudan. 19937903141
identification of phlebotomine sandfly bloodmeals from baringo district, kenya, by direct enzyme-linked immunosorbent assay (elisa).direct enzyme-linked immunosorbent assay (elisa) was used to identify the sources of bloodmeals in phlebotomine sandflies from baringo district, rift valley province, kenya. some bloodmeals had been stored for over 4 years before being analysed. among 356 sandflies identified, 62.9% were phlebotomus martini, 14.8% sergentomyia antennatus, 10% s.schwetzi, 6% s.clydei, 1.9% s.adleri, 1.6% p.duboscqi, 1.4% s.africanus and 0.8% s.bedfordi. out of 224 p.martini bloodmeals, host source was identified ...19921463906
epidemic visceral leishmaniasis in southern sudan: identity and systematic position of the parasites from patients and vectors.twenty-five strains of leishmania donovani isolated from humans and phlebotomus orientalis in an epidemic area of southern sudan were shown to belong to 3 very similar zymodemes: mon 18 (11 strains), mon 30 (1 strain) and mon 82 (13 strains). the 3 zymodemes are very closely related and seem to behave as a single population.19921440811
isolation of leishmania donovani from phlebotomus martini in baringo district, kenya.an 18-month sandfly survey was conducted at 4 locations in baringo district, rift valley province, kenya. 3 collection techniques were used: aspiration, sticky paper trap, and light trap in sites selected because of their proximity to homes of visceral leishmaniasis patients diagnosed and treated within 6 months before the survey. over 2000 female phlebotomus martini were collected of which 6 females were found to have flagellate protozoan infections. 3 of these infections were cultured successf ...19883252587
heat shock and the relative hexokinase activity of leishmania aethiopica and leishmania donovani. 19883215177
leishmania donovani parasites in the nasal secretions, tonsillopharyngeal mucosa, and urine centrifugates of visceral leishmaniasis patients in kenya.in the early 1930s, investigators of visceral leishmaniasis stated that leishman-donovan bodies are found in body fluids of kala-azar patients, for example, in urine, feces, semen, and nasal and pharyngeal secretions. based on this finding, we investigated the diagnostic potential of nasal secretions, tonsillopharyngeal mucosal swabs, and urine centrifugates inoculated into schneider's drosophila medium (containing antibiotics and antifungal agents) as well as with giemsa-stained smears. consequ ...19938480861
evaluation of the direct agglutination test (dat) using freeze-dried antigen for the detection of anti-leishmania antibodies in stored sera from various patient groups in ethiopia.tests on a panel of 421 serum samples from ethiopia and 11 from europe with the direct agglutination test (dat) and freeze-dried antigen (leishmania donovani 1s) showed that a cut-off titre of 1:200 or 1:400 could be employed. using a cut-off titre of 1:400, 181 (88.3%) of 205 serum samples from visceral leishmaniasis (vl) patients tested positive, as did 5 (13.9%) of 36 sera from patients with localized cutaneous leishmaniasis, 5 (71.4%) sera from 7 patients with diffuse cutaneous leishmaniasis ...199910492758
sudanese mucosal leishmaniasis: epidemiology, clinical features, diagnosis, immune responses and treatment.the epidemiology, clinical features, pathology, immune responses, diagnosis and treatment of 14 patients with mucosal leishmaniasis in the sudan are described. the condition occurred mainly in adult males, particularly in certain closely related tribes from the western sudan. it affected the mucosa of the upper respiratory tract and/or the oral mucosa and sometimes followed treated kala azar. the parasites were sometimes confined to the mucosa, sometimes spread to the lymph nodes, and rarely inf ...19958594683
epidemiology and clinical manifestations of visceral and cutaneous leishmaniasis in baringo district, rift valley, kenya. a literature review.visceral leishmaniasis (vl), caused by leishmania donovani, is endemic in baringo district, kenya. the disease has a focal distribution in the dry, hot areas below 1500 metres. infections may be characterized as follows: 1) asymptomatic, 2) subclinical and self-limiting (not medically identifiable), and 3) clinically manifest disease (that is medically identifiable). half of the reported vl patients are between 5 and 14 years of age and 66% of them are males. the reasons for the focal distributi ...19947940999
human cutaneous leishmaniasis caused by leishmania donovani s.l. in kenya.our laboratory is characterizing leishmania stabilates and isolates from active leishmaniasis cases. smears and cultures from aspirates made on different dates from a single lesion on the bridge of the nose of an 18 years old kenyan male from nyandarua district contained leishmania. the isolates, nlb-271 and nlb-271-ia, were characterized by cellulose acetate electrophoresis (cae) using 20 enzyme systems and by southern analysis using 2 deoxyribonucleic acid (dna) probes (pdk10 and pdk20) from a ...19938266420
leishmania donovani parasitaemia in kenyan visceral leishmaniasis.twenty kenyan patients with visceral leishmaniasis were evaluated for the presence of leishmania donovani in their peripheral blood. smears, cultures and hamster inoculations detected parasitaemia in 11, 10 and six patients, respectively, and at least one method detected parasitaemia in 15 patients (75%). the likelihood of detecting parasitaemia correlated with the density of parasites in splenic aspirate smears. it is apparent that parasitaemia with l. donovani occurs frequently in kenyan patie ...19854002290
random amplified polymorphic dna for the differentiation of leishmania donovani isolates from sudan. 19968761592
leishmaniasis in the sudan republic. 29. comparison and epidemiological implications of experimental canine infections with sudanese, mediterranean, and kenyan strains of leishmania donovani. 19705421087
studies on the leishmaniases in the sudan. 3. clinical and parasitological studies on visceral and mucosal leishmaniasis.the epidemiological, clinical and laboratory findings of 27 patients with visceral leishmaniasis (vl) and six with mucosal leishmaniasis (ml) in sudan are described. the diagnosis was confirmed by the demonstration of amastigotes in bone-marrow in 20 cases with vl (80%) and impression smears in 2 cases with ml. the enzyme-linked immunosorbent assay and direct agglutination test were positive in all the sera tested. the leishmanin test was positive in all patients with ml, the diameter of the rea ...19911755050
detection of antibodies to leishmania donovani in animals in a kala-azar endemic region in eastern sudan: a preliminary report.the prevalence of antibodies against leishmania donovani in selected domestic and wild animal species in 2 villages in sudan with active l. donovani transmission in humans was investigated. screening of domestic animals (donkeys, cows, sheep, goats, camels and dogs) with the direct agglutination test (dat) detected reaction rates above the cut-off titres in donkeys (68.7%), cows (21.4%) and goats (8.5%), and which were also found in wild rats (5.5%). sera of sheep, camels and dogs had a weak agg ...200010748894
latex agglutination test for the detection of urinary antigens in visceral leishmaniasis.this paper describes a new latex agglutination test ('katex') for the detection of leishmanial antigen in the urine of patients with visceral leishmaniasis. in preliminary laboratory trials, using urine collected from well-defined cases and controls from brazil, yemen and nepal, the test had 100% specificity and a sensitivity between 68 and 100%. when used in a time-course experiment in cotton rats infected with leishmania donovani, the test became positive 1 week after inoculation and antigen l ...200111164745
infection rates of leishmania donovani in phlebotomus orientalis from a focus of visceral leishmaniasis in eastern sudan. 19989625920
epidemiology of leishmaniases in kenya. natural host preference of wild caught phlebotomine sandflies in baringo district, kenya.host preference of wild caught phlebotomine sandflies was studied in marigat, baringo district, kenya, an endemic focus for both leishmania donovani laveran & mensel and l. major yakimov & schokhov using precipitin test of blood meals. sandflies of the phlebotomus rondani & berte and sergentomyia franc & parrot genera were encountered blood fed and resting in nine different habitats which were investigated. analysis of their blood meals revealed a distinct host preference between the phlebotomus ...19902390954
the interplay between environmental and host factors during an outbreak of visceral leishmaniasis in eastern sudan.parasitic diseases, including human visceral leishmaniasis, are multifactorial. factors that are expected to play an important role in the parasite-human interaction are exposure, parasite "virulence" and host resistance factors. in populations exposed to leishmania donovani most subjects do not allow the parasites to establish themselves or remain asymptomatic. some individuals, however, fail to control parasite expansion and dissemination and develop a visceral disease. we report here the resu ...200212475635
characterization of the glucosyltransferases that assemble the side chains of the indian leishmania donovani lipophosphoglycan.the life cycle of leishmania parasites within its sand fly vector involves the development of extracellular promastigotes from a noninfective, "procyclic" stage into an infective, "metacyclic" stage that is adapted for transmission in the fly and survival in the mammalian host. lipophosphoglycan (lpg), the predominant surface glycoconjugate in both procyclic and metacyclic stages, is a critical virulence determinant. lpg is a multidomain molecule; the structural polymorphisms among species lie i ...199910600177
leishmania donovani: intraspecific polymorphisms of sudanese isolates revealed by pcr-based analyses and dna sequencing.four polymerase chain reaction (pcr)-based approaches were used to analyze diversity within 23 sudanese isolates of leishmania donovani. methods compared were fingerprinting with single nonspecific primers, restriction analysis of the amplified ribosomal internal transcribed spacer (its) locus, single-stranded conformation polymorphism (sscp), and sequencing of the its region. when pcr fingerprinting and restriction analysis of its were applied, highly similar fragment patterns were observed for ...200111207112
genetic control of visceral leishmaniasis in a sudanese population: candidate gene testing indicates a linkage to the nramp1 region.there is some evidence showing that genetic factors are involved in human susceptibility to parasitic diseases such as schistosomiasis and malaria. studies have shown that the nramp1 and h-2 genes are implicated in the control of leishmania donovani infection in mice. we sought genetic loci involved in the control of susceptibility to visceral disease caused by l. donovani in humans. we studied 37 families with at least two affected sibs living in a village in eastern sudan, where an outbreak of ...200312618857
genetic susceptibility to visceral leishmaniasis in the sudan: linkage and association with il4 and ifngr1.longitudinal studies in sudan show ethnic differences in incidence and clinical phenotypes associated with leishmania donovani. immunologically, bias in type 1 vs type 2 cytokine responses is important. to determine whether polymorphisms at il4/il9 or ifngr1 contribute to susceptibility, we examined 59 multicase families of visceral leishmaniasis (vl) with/without post kala-azar dermal leishmaniasis (pkdl). multipoint nonparametric analysis (allegro) linked il4/il9 to vl per se (p=0.002). transm ...200312847550
oronasal leishmaniasis caused by a parasite with an unusual isoenzyme profile.a 45-year-old sudanese man from western sudan presented with oronasal leishmaniasis of three years duration. he had no history of previous kala-azar or cutaneous leishmaniasis. the parasite isolated from the oral mucosa was characterized by isoenzymes using 12 enzymes and by polymerase chain reaction amplification of kinetoplast dna using species-specific primers. the specific primers gave products indistinguishable from those of the leishmania donovani complex. however, the isoenzyme profile sh ...19979063369
ancistrotanzanine a, the first 5,3'-coupled naphthylisoquinoline alkaloid, and two further, 5,8'-linked related compounds from the newly described species ancistrocladus tanzaniensis.the first phytochemical investigation of the recently discovered east african liana ancistrocladus tanzaniensis is described, resulting in the isolation and structural elucidation of two new naphthylisoquinoline alkaloids, ancistrotanzanines a (5) and b (6), and the known compound ancistrotectoriline a (7). ancistrotazanine a (5) represents a hitherto unprecedented 5,3'-coupling type between the naphthalene and isoquinoline portions, while 6 and 7 are 5,8'-coupled. the structures of the compound ...200314510589
visceral leishmaniasis in somalia: prevalence of leishmanin-positive and seropositive inhabitants in an endemic area.in an endemic area of somalia both humoral and cell mediated immunity against leishmania donovani was demonstrated in 246 inhabitants. in a study of 14 patients with active visceral leishmaniasis, we found that antibodies appear early in infection and that they are then demonstrable for a limited period only. leishmanin positivity develops later and persists longer, but does not seem to be lifelong. the majority of the immunoreactive individuals were either sero- or leishmanin positive. this fin ...19957747298
epidemiology and clinical manifestations of leishmania donovani infection in two villages in an endemic area in eastern sudan.we conducted a longitudinal study in an endemic area for visceral leishmaniasis (vl) in eastern sudan to compare the epidemiology and clinical spectrum of leishmania donovani infection in two populations differing in ethnic background and duration of residence in the area. the study took place in two villages from april 1994 to april 1996. in um-salala village, which is inhabited by members of the masaleet tribe, half of the villagers had previous exposure to cutaneous leishmaniasis (leishmaria ...200211851953
the egyptian mongoose, herpestes ichneumon, is a possible reservoir host of visceral leishmaniasis in eastern sudan.investigations were made on possible reservoir hosts of leishmania donovani in 2 zoonotic foci of visceral leishmaniasis (vl) in dinder national park (dnp) and the peri-domestic habitats of adjacent villages of eastern sudan. animals were captured, in november 1997-1998 and april-may 1999 and examined for l. donovani infection using light microscopy and 2 sensitive polymerase chain reaction (pcr) systems. microscopy and pcr investigations were also used to determine the infection rates of l. don ...200111393826
comparison of two geographic strains of leishmania donovani by resistance of mice to superinfection.groups of mice were injected with leishmania donovani strains et (burma) or is (sudan) and the courses of infection were followed. between days 20 and 30 after infection by treatment with pentostam. et- and 1s-recovered mice were challenged by intravenous injection of amastigotes of each strain. although resistance to superinfection was apparent the l. donovani strains could not be differentiated by this method.1975125553
post-kala-azar dermal leishmaniasis: does it play a role in the transmission of leishmania donovani in the sudan?in 1997 a sudden outbreak of visceral leishmaniasis (vl) occurred in eastern sudan, coinciding with an increase of post-kala-azar dermal leishmaniasis (pkdl) cases which may in part be because of sylvatic and anthroponotic transmission. paradoxically, the more vl patients are treated, the higher the frequency of pkdl. if pkdl plays a role in transmission, its treatment would be expected to reduce infection in the area. treatment of pkdl, however, requires four times the amount of pentostam used ...200111555443
kala-azar in a high transmission focus: an ethnic and geographic dimension.in 1994-1996, we studied a group of 58 game wardens stationed in an area known to be highly endemic for visceral leishmaniasis (kala-azar) for evidence of infection with leishmania donovani. leishmania dna was detected by the polymerase chain reaction in the peripheral blood of cases of active kala-azar, former patients with visceral leishmaniasis, patients, and asymptomatic subjects. using the cloned antigen rk39, antibodies were detected in 44.2% of the game wardens while leishmanin skin test ...199910674674
first identification of the causative agent of visceral leishmaniasis in djibouti: leishmania donovani.the first identification of the leishmania species responsible for visceral leishmaniasis in djibouti is described. four strains, obtained from three autochthonous cases, were identified by starch-gel electrophoresis and iso-enzyme analysis of 15 enzymatic systems. the strains were found to belong to two newly recognized zymodemes of l. donovani: mon-268 and mon-287.200515701251
diagnosis of visceral leishmaniasis by the polymerase chain reaction using blood, bone marrow and lymph node samples from patients from the sudan.we have evaluated the sensitivity of the polymerase chain reaction (pcr) as a diagnostic tool for leishmania donovani using blood, bone marrow and lymph node samples from sudanese patients with a confirmed infection. forty patients were diagnosed by microscopic examination of bone marrow or lymph node samples. the pcr was able to detect parasite dna in 37 out of 40 blood samples. in bone marrow and lymph node samples, the pcr was able to detect parasite dna in all 7 and 6 samples, respectively. ...19979217699
bronchopulmonary and mediastinal leishmaniasis: an unusual clinical presentation of leishmania donovani infection.we describe a case of unusual leishmaniasis in a sudanese man with a history of progressively enlarging granulomatous mediastinal lymphadenopathy, worsening hemoptysis, and an intense mucosal granulomatous inflammatory response in the large bronchi. leishmania donovani dna was detected in bronchial biopsies by polymerase chain reaction. this is a novel description of human leishmanial infection in an immunocompetent patient involving this anatomical site. the patient's condition improved clinica ...200010816146
a phase ii dose-increasing study of sitamaquine for the treatment of visceral leishmaniasis in kenya.sitamaquine (wr6026) is an 8-aminoquinoline in development for the oral treatment of visceral leishmaniasis (vl). this was an open-label, dose-increasing study to determine the dose-response and safety profile for sitamaquine in kenyan patients with vl caused by leishmania donovani. patients (mean age 15.9 [range = 5-47] years) received sitamaquine daily for 28 days at one of four doses: 1.75 (n = 12), 2.0 (n = 61), 2.5 (n = 12), or 3.0 (n = 12) mg/kg/day. the primary efficacy outcome was cure ( ...200516282296
protective efficacy of lambdacyhalothrin-impregnated bednets against phlebotomus orientalis, the vector of visceral leishmaniasis in sudan.field investigations on the sandfly phlebotomus orientalis (diptera: psychodidae), the vector of leishmania donovani causing visceral leishmaniasis (vl) in sudan, were undertaken in two villages (bellow and elgamel) and dinder national park, to determine the protective value of bednets (polyester, 100 denier) impregnated with lambda-cyhalothrin 10 mg a.i./m2 pyrethroid insecticide. after exposure to treated netting for 30 s, p. orientalis females all died within 1 h. when field-tested in acacia ...199910514058
arbitrary-primed pcr for genomic fingerprinting and identification of differentially regulated genes in indian isolates of leishmania donovani.the arbitrary-primed pcr (ap-pcr) technique was employed with the twin goals of identifying genetic polymorphisms within the indian isolates and to identify differentially expressed gene sequences. the parasite isolates from indian kala-azar patients could be differentiated from leishmania donovani isolates from distinct geographic regions. moreover, differences within the indian isolates could also be identified. a majority (17/19) of the indian isolates gave identical ap-pcr pattern, while two ...200415172218
sudanese mucosal leishmaniasis: isolation of a parasite within the leishmania donovani complex that differs genotypically from l. donovani causing classical visceral leishmaniasis.mucosal leishmaniasis, which is a sporadic disease in the sudan, was shown by isoenzyme characterization and pcr to be caused by leishmania donovani. however, it was not clear if the parasite was exactly the same strain as that causing visceral leishmaniasis (vl), or of a different strain. we utilized a new generation of molecular dna markers, minisatellites and kinetoplast dna, for rapid characterization of the parasite. the results show that the genotypes of some of the parasites causing vl ar ...200515567136
detection of high rates of in-village transmission of leishmania donovani in eastern sudan. 200415301978
visceral leishmaniasis in eastern sudan: parasite identification in humans and dogs; host-parasite relationships.in 1996, an epidemic outbreak of visceral leishmaniasis (vl) started in barbar el fugara, a village in gedarif state (eastern sudan). from 1997 to 2000, regular epidemiological studies were carried out in the human population, as well as in mammals and sand flies. in symptomatic patients, 46/69 lymph node, 6/20 post kala-azar dermal leishmaniasis (pkdl) and 1/4 cutaneous cultures in nnn medium were positive. in 69 dogs, 23/79 lymph node cultures were positive. in other mammals (47 rodents, five ...200314554251
elevated plasma levels of interferon (ifn)-gamma, ifn-gamma inducing cytokines, and ifn-gamma inducible cxc chemokines in visceral leishmaniasis.interferon (ifn)- gamma plays an important role during immune responses against leishmaniasis. production of ifn-gamma is regulated by interleukin (il)-12, il-18, and il-15. interferon-gamma-inducible protein (ip)-10 and monokine induced by ifn-gamma (mig) are cxc chemokines, the production of which, at least in part, is ifn-gamma dependent. a follow-up study of individuals infected with leishmania donovani was undertaken in an area of ethiopia endemic for visceral leishmaniasis (vl). plasma lev ...200415569785
leishmaniasis in sudan. post kala-azar dermal leishmaniasis.post kala-azar dermal leishmaniasis (pkdl) is increasingly recognized in sudan as a complication of visceral leishmaniasis (vl), occurring in c. 55% of patients after, or during treatment of, vl. the development of pkdl seems to be restricted to parasites of the leishmania donovani sensu stricto cluster; no particular zymodeme has been found to be associated with it. in contrast to pkdl in india, pkdl in sudan occurs within 0-6 months after treatment for vl. the rash may be macular, maculo-papul ...200111370251
slc11a1 (formerly nramp1) and susceptibility to visceral leishmaniasis in the sudan.genetic susceptibility to visceral leishmaniasis (vl) is indicated by differences in incidence and clinical phenotypes between ethnic groups in sudan. in mice, innate susceptibility to leishmania donovani, the etiological agent of vl, is controlled by slc11a1 (formerly nramp1). we therefore examined polymorphisms at slc11a1 in 59 multicase families of vl from the high-incidence masalit tribe in sudan. multipoint nonparametric analysis in allegro shows a significant linkage across slc11a1 (zlr sc ...200414523377
post-kala-azar dermal leishmaniasis.post-kala-azar dermal leishmaniasis (pkdl) is a complication of visceral leishmaniasis (vl); it is characterised by a macular, maculopapular, and nodular rash in a patient who has recovered from vl and who is otherwise well. the rash usually starts around the mouth from where it spreads to other parts of the body depending on severity. it is mainly seen in sudan and india where it follows treated vl in 50% and 5-10% of cases, respectively. thus, it is largely restricted to areas where leishmania ...200312560194
leishmaniasis in sudan. mucosal leishmaniasis.sudanese mucosal leishmaniasis is a chronic infection of the upper respiratory tract and/or oral mucosa caused mainly by leishmania donovani. the disease occurs in areas of the country endemic for visceral leishmaniasis, particularly among masalit and other closely related tribes in western sudan. the condition may develop during or after an attack of visceral leishmaniasis, but in most cases it is a primary mucosal disease. unlike south american mucocutaneous leishmaniasis, mucosal leishmaniasi ...200111370249
the origin and evolution of the leishmania donovani complex as inferred from a mitochondrial cytochrome oxidase ii gene sequence.members of the leishmania donovani complex are parasites of the reticulo-endothelial system that are often associated with serious epidemics of a life threatening disease known as visceral leishmaniasis or kala-azar. twenty-two leishmania isolates representative of the geographical range of the parasite were analysed for sequence variations in their cytochrome oxidase ii gene. in performing phylogenetic analysis, the maximum parsimonious, neighbour joining and maximum likelihood trees were congr ...200112798051
leishmania donovani is the only cause of visceral leishmaniasis in east africa; previous descriptions of l. infantum and "l. archibaldi" from this region are a consequence of convergent evolution in the isoenzyme data.isoenzyme-based studies have identified 3 taxa/species/'phylogenetic complexes' as agents of visceral leishmaniasis in sudan: l. donovani, l. infantum and "l. archibaldi". however, these observations remain controversial. a new chitinase gene phylogeny was constructed in which stocks of all 3 putative species isolated in sudan formed a monophyletic clade. in order to construct a more robust classification of the l. donovani complex, a panel of 16 microsatellite markers was used to describe 39 st ...200415521628
concordant hiv infection and visceral leishmaniasis in ethiopia: the influence of antiretroviral treatment and other factors on outcome.coinfection with human immunodeficiency virus (hiv) and leishmania donovani visceral leishmaniasis (vl) in africa is an emerging, poorly understood disease.200818419422
a diagnostic assay based on variable intergenic region distinguishes between leishmania donovani and leishmania infantum.we have developed a pcr assay that in a single reaction distinguishes between leishmania infantum and leishmania donovani strains on the basis of different size of the amplicon. the targeted intergenic region between putative biopterin transporter and nucleotide binding protein on chromosome 35 is highly variable, species-specific and can be amplified from clinical samples. based on the assay, five tested leishmania archibaldi and l. infantun strains from the sudan and ethiopia clearly belong to ...200818578169
a neglected disease of humans: a new focus of visceral leishmaniasis in bakool, somalia.visceral leishmaniasis (vl) was observed in children in bakool region, somalia, an area where vl has not been reported before. we describe the extent of the problem in this war- and famine-stricken area. a retrospective analysis was done of all cases admitted to a vl treatment centre between july 2000 and august 2001. patients with longstanding fever, splenomegaly and a positive direct agglutination test (dat; titre > 1:3200) were treated as suspected vl cases. a rapid epidemiological and entomo ...200316117959
the pathogenesis of post kala-azar dermal leishmaniasis from the field to the molecule: does ultraviolet light (uvb) radiation play a role?post kala-azar dermal leishmaniasis (pkdl) is a dermatosis caused by persistence of leishmania donovani parasites in the skin following apparently successful treatment of visceral leishmaniasis. the distribution of pkdl lesions in sudanese patients often mirrors the clothing habits of those affected. it is most severe in or confined to the sun-exposed parts of the skin. it is well established that elimination of leishmania parasites requires activation of parasitised macrophages by a th1 immune ...200616386855
diverse viscerotropic isolates of leishmania all express a highly conserved secretory nuclease during human infections.previously, we characterized a gene encoding the unique nuclease (ldnuc(s)) from a sudanese isolate of the human pathogen leishmania donovani. this parasite secretory enzyme is involved in the salvage of host-derived purines and is constitutively expressed by both developmental forms of the parasite. currently, we assessed whether an ldnuc(s)-like nuclease was conserved among other geographically disparate isolates of l. donovani and whether this enzyme was produced by intracellular amastigotes ...201222020747
factors affecting variations in exposure to infections by leishmania donovani in eastern sudan.a cross-sectional survey was carried out in gedaref state, eastern sudan to investigate the prevalence of positive leishmanin skin tests and environmental factors related to leishmania donovani infection. a total of 3835 people living in 11 villages in 3 regions were screened. soil types and tree densities were determined in 33 villages inhabited by 44 different tribes. the highest rates of positive skin tests were in rahad region (33.9%), atbara (21.6%) and gedaref (10.6%), with an average of 2 ...200315748079
isolation and identification of leishmania donovani from phlebotomus orientalis, in an area of eastern sudan with endemic visceral leishmaniasis. 200818782494
biochemical and molecular characterization of leishmania parasites isolated from an endemic focus in eastern sudan.twelve leishmania isolates from visceral leishmaniasis patients in eastern sudan were characterized using isoenzyme analysis, southern blotting and polymerase chain reaction (pcr) 'fingerprinting'. isoenzyme analysis revealed the presence of 3 zymodemes: mon-18, mon-30 and mon-82, corresponding to leishmania donovani sensu stricto, l. infantum and l. archibaldi (still of uncertain taxonomic status), respectively. southern blotting and pcr 'fingerprinting' revealed identical patterns for all 3 zy ...19989692173
quantifying the contribution of hosts with different parasite concentrations to the transmission of visceral leishmaniasis in ethiopia.an important factor influencing the transmission dynamics of vector-borne diseases is the contribution of hosts with different parasitemia (no. of parasites per ml of blood) to the infected vector population. today, estimation of this contribution is often impractical since it relies exclusively on limited-scale xenodiagnostic or artificial feeding experiments (i.e., measuring the proportion of vectors that become infected after feeding on infected blood/host).201425356795
antiprotozoal polyacetylenes from the tanzanian medicinal plant cussonia zimmermannii.from the petroleum ether extract of the root bark of cussonia zimmermannii four polyacetylenes, 1- 4, were isolated, three of which ( 1- 3) were active against trypanosoma brucei rhodesiense, trypanosoma cruzi, plasmodium falciparum, and leishmania donovani.200717922552
infection rates with leishmania donovani and mycobacterium tuberculosis in a village in eastern sudan.leishmania-tuberculosis co-infection is not uncommon in clinical practice in east africa, but little is known about the epidemiology of this problem at population level. a cross-sectional household survey was carried out in an active visceral leishmaniasis (vl) focus in eastern sudan in february 2002.200415598262
qualitative and semi-quantitative comparison of an rk39 strip test and direct agglutination test for detection of anti-leishmania donovani antibodies in the sudan.until now, the comparison of the rk39 strip test (rkt) and direct agglutination test (dat) for detection of visceral leishmaniasis (vl) is exclusively based on either positive or negative qualification of the reaction outcome.200920054109
humoral and cellular immune responses to glucose regulated protein 78 -- a novel leishmania donovani antigen.the recently cloned glucose regulated protein 78 (grp78) of leishmania donovani has been suggested as a new and promising leishmania vaccine candidate. we assessed antibody and t-cell reactivity to grp78 in an enzyme-linked immunosorbent assay (elisa) and in lymphoproliferative assays. serological evaluation of plasma samples obtained in sudan revealed that 89% of patients with visceral leishmaniasis (vl), 78% with post kala-azar dermal leishmaniasis (pkdl), and 85% with cutaneous leishmaniasis ...200212000658
leishmania donovani: an in vitro study of antimony-resistant amphotericin b-sensitive isolates.drug sensitivity of clinically antimony-unresponsive leishmania donovani isolates from eastern sudan was evaluated in an in vitro culture system against sodium stibogluconate (pentostam) and amphotericin b. eight isolates, six from antimony-resistant and two from clinically responsive patients were included in the study. parasites were tested as promastigotes and four of them were selected to be tested as amastigotes using a murine macrophage-like cell line. the results indicated that the conven ...200616716301
serological evidence of leishmania donovani infection in apparently healthy dogs using direct agglutination test (dat) and rk39 dipstick tests in kafta humera, north-west ethiopia.leishmania (kinetoplastida: trypanosomatidae) are protozoan parasites of significant medical and veterinary importance. over the last decade, visceral leishmaniasis (vl) has emerged as a major opportunistic infection associated with hiv/aids in north western ethiopia. this paper reports on serological evidence of possible leishmania donovani (l. donovani) infection in dogs using two serological tests: direct agglutination test (dat) and kalazar detect rapid test (kdrt). two hundred and seventeen ...201121371289
the paraphyletic composition of leishmania donovani zymodeme mon-37 revealed by multilocus microsatellite typing.multilocus microsatellite typing (mlmt) was employed to compare strains of leishmania donovani belonging to the mon-37 zymodeme (mon-37 strains) from cyprus and israel to mon-37 strains from the indian subcontinent, the middle east, china and east africa as well as strains of other zymodemes. the mlmt data were processed with a distance-based method for construction of phylogenetic trees, factorial correspondence analysis and a bayesian model-based clustering algorithm. all three approaches assi ...200919376262
essential-oil composition, antileishmanial, and toxicity study of artemisia abyssinica and satureja punctata ssp. punctata from ethiopia.essential oils of artemisia abyssinica and satureja punctata ssp. punctata from ethiopia were analyzed by gc and gc/ms, and screened for leishmanicidal activity against promastigote and axenic amastigotes of leishmania donovani and l. aethiopica, including toxicity studies on human monocytic leukemia cells (thp-1) and erythrocytes in vitro. gc/ms of a. abyssinica oil revealed 67 compounds (99.94%) with the major constituents yomogi alcohol (38.47%), artemisyl acetate (24.88%), and artemisia alco ...201020397218
immunogenicity and safety of autoclaved leishmania major plus bcg vaccine in healthy sudanese volunteers.in a longitudinal study in the epidemiology of leishmania donovani infection in an endemic focus in eastern sudan, we observed that previous exposure or infection with leishmania major appeared to protect against visceral leishmaniasis caused by l. donovani. we therefore conducted a study to test the safety and immunogenicity of a vaccine consisting of autoclaved l. major (alm) plus bcg in inducing protection in vaccinated individuals. leishmanin-negative healthy sudanese volunteers were enrolle ...200111228382
disseminated cutaneous leishmaniasis resembling post-kala-azar dermal leishmaniasis caused by leishmania donovani in three patients co-infected with visceral leishmaniasis and human immunodeficiency virus/acquired immunodeficiency syndrome in ethiopia.abstract. we report paired strains of leishmania parasites, one from the viscera and the other from skin lesions that were isolated from three patients with visceral leishmaniasis and disseminated cutaneous leishmaniasis that were co-infected with human immunodeficiency virus. the causative parasites were characterized by polymerase chain reaction-restriction length polymorphism of the ribosomal dna internal transcribed spacer 1 and by a panel of multilocus microsatellite markers. we demonstrate ...201121633027
Multifaceted Population Structure and Reproductive Strategy in Leishmania donovani Complex in One Sudanese Village.Leishmania species of the subgenus Leishmania and especially L. donovani are responsible for a large proportion of visceral leishmaniasis cases. The debate on the mode of reproduction and population structure of Leishmania parasites remains opened. It has been suggested that Leishmania parasites could alternate different modes of reproduction, more particularly clonality and frequent recombinations either between related individuals (endogamy) or between unrelated individuals (outcrossing) withi ...201122206035
use of a newly developed beta-mercaptoethanol enzyme-linked immunosorbent assay to diagnose visceral leishmaniasis in patients in eastern sudan.corroboration of serology results is essential for restricting the risk of inappropriate antileishmanial prescription. a direct agglutination test (dat) and a recently developed beta-mercaptoethanol-modified enzyme-linked immunosorbent assay (beta-me elisa) based on the use of antigen prepared as described for the dat were applied to 416 sera from two sudanese populations with and without clinical evidence of visceral leishmaniasis (vl). of 285 sera with the lowest antileishmanial dat titers (</ ...200717942614
first report on ambisome-associated allergic reaction in two sudanese leishmaniasis patients.post kala-azar dermal leishmaniasis (pkdl) and mucosal leishmaniasis (ml) are serious clinical forms of leishmaniasis caused by leishmania donovani parasites in sudan. although pentavalent antimonys are used as the first line of treatment of all clinical forms of leishmaniasis, persistent pkdl and ml patients are treated with liposomal amphotericin b (ambisome) as a second-line drug. in this work, we report the development of allergic reactions by a pkdl and a ml sudanese patient to ambisome. th ...201121976565
validation of a β-me elisa for detection of anti leishmania donovani antibodies in eastern sudan.a β-mercaptoethnol (β-me)-treated promastigote antigen of l. donovani was successfully employed in direct agglutination test (dat) for the diagnosis of visceral leishmaniasis (vl).201121931201
optimization of loop-mediated isothermal amplification (lamp) assays for the detection of leishmania dna in human blood samples.visceral leishmaniasis (vl), one of the most important neglected tropical diseases, is caused by leishmania donovani eukaryotic protozoan parasite of the genus leishmania, the disease is prevalent mainly in the indian sub-continent, east africa and brazil. vl can be diagnosed by pcr amplifying its1 and/or kdna genes. the current study involved the optimization of loop-mediated isothermal amplification (lamp) for the detection of leishmania dna in human blood or tissue samples. three lamp systems ...201627288706
development and comparative evaluation of two antigen detection tests for visceral leishmaniasis.visceral leishmaniasis (vl) can be fatal without timely diagnosis and treatment. treatment efficacies vary due to drug resistance, drug toxicity and co-morbidities. it is important to monitor treatment responsiveness to confirm cure and curtail relapse. currently, microscopy of spleen, bone marrow or lymph node biopsies is the only definitive method to evaluate cure. a less invasive test for treatment success is a high priority for vl management.201526395447
mucosal leishmaniasis in a sudanese patient.mucosal leishmaniasis (ml) is an oral disease caused by the parasite leishmania donovani. the disease has been proven to be pandemic in many areas of the world. it affects young men living in leishmaniasis-endemic areas. ml might be accompanied or proceeded by visceral leishmaniasis (vl), although in most of the cases seen in sudan, ml occurs as a primary lesion. ml can mimic oral cancer or fungal infections, with ulceration as the most common finding in ml lesions. in this report, the patient c ...200919478252
multilocus microsatellite typing revealed high genetic variability of leishmania donovani strains isolated during and after a kala-azar epidemic in libo kemkem district, northwest ethiopia.in 2004, an outbreak of kala-azar (ka) occurred for the first time in libo kemkem district, in the highland area of northwest ethiopia. in order to track the possible origins of the outbreak parasites, we have investigated 19 strains of leishmania donovani that were collected during (n = 6) and after (n = 13) the outbreak by using 14 highly polymorphic microsatellite markers. unique microsatellite profiles were obtained for all strains from libo kemkem. when compared to those of l. donovani stra ...201121382503
exposure to leishmania spp. and sand flies in domestic animals in northwestern ethiopia.human visceral leishmaniasis caused by leishmania donovani is considered an anthroponosis; however, leishmania-infected animals have been increasingly reported in l. donovani foci, and the role of these animals as reservoirs for human l. donovani infection remains unclear.201526152578
nocturnal periodicity of phlebotomus (larroussius) orientalis (diptera: psychodidae) in an endemic focus of visceral leishmaniasis in northern ethiopia.phlebotomus orientalis is the major vector of the intramacrophage protozoa, leishmania donovani, the etiological agent of visceral leishmaniasis (vl) in northern ethiopia and sudan. the objective of this study was to determine the nocturnal periodicity of p. orientalis in the vl endemic focus of tahtay adiyabo district, northern ethiopia.201525889314
y chromosome lineage- and village-specific genes on chromosomes 1p22 and 6q27 control visceral leishmaniasis in sudan.familial clustering and ethnic differences suggest that visceral leishmaniasis caused by leishmania donovani is under genetic control. a recent genome scan provided evidence for a major susceptibility gene on chromosome 22q12 in the aringa ethnic group in sudan. we now report a genome-wide scan using 69 families with 173 affected relatives from two villages occupied by the related masalit ethnic group. a primary ten-centimorgan scan followed by refined mapping provided evidence for major loci at ...200717500593
genes and environment in susceptibility to visceral leishmaniasis.kala azar (ka) is a lethal disease caused by leishmania parasites (leishmania donovani s.l.) that multiply in large numbers in deep organs such as spleen and liver. the host immunological response to these organisms is complex and experimental studies in animals have detected a large number of genetic loci involved in the control of infection and disease. we report here on a study in a human population of sudan carried out during an outbreak of ka. the following conclusions are presented: (1) en ...200617067929
identification of leishmania donovani as a cause of cutaneous leishmaniasis in sudan.eight patients with cutaneous ulcers were referred to the institute of endemic diseases, khartoum, sudan, from june 2000 to march 2002 for the diagnosis of suspected cutaneous leishmaniasis (cl). diagnosis was confirmed parasitologically by both positive giemsa-stained smears and successful culture of leishmania promastigotes in nnn medium. the eight parasite isolates were shown to belong to the leishmania donovani complex by kdna pcr. isoenzyme typing of three isolates revealed that they were i ...200818037149
nocturnal activities and host preferences of phlebotomus orientalis in extra-domestic habitats of kafta-humera lowlands, kala-azar endemic, northwest ethiopia.phlebotomus orientalis feeds on a variety of wild and domestic animals and transmits leishmania donovani from hitherto unknown reservoir hosts to humans in extra-domestic habitats in the metema-humera lowlands. the aim of this study was to determine the nocturnal activities of p. orientalis and its preferred blood meal hosts.201425515239
inference of population structure of leishmania donovani strains isolated from different ethiopian visceral leishmaniasis endemic areas.parasites' evolution in response to parasite-targeted control strategies, such as vaccines and drugs, is known to be influenced by their population genetic structure. the aim of this study was to describe the population structure of ethiopian strains of leishmania donovani derived from different areas endemic for visceral leishmaniasis (vl) as a prerequisite for the design of effective control strategies against the disease.201021103373
multilocus sequence and microsatellite identification of intra-specific hybrids and ancestor-like donors among natural ethiopian isolates of leishmania donovani.protozoan parasites of the genus leishmania (kinetoplastida: trypanosomatidae) cause widespread and devastating human diseases. visceral leishmaniasis is endemic in ethiopia where it has also been responsible for fatal epidemics. it is postulated that genetic exchange in leishmania has implications for heterosis (hybrid vigour), spread of virulent strains, resistance to chemotherapeutics, and exploitation of different hosts and vectors. here we analyse 11 natural ethiopian leishmania donovani is ...201424995620
leishmania donovani: genetic diversity of isolates from sudan characterized by pcr-based rapd.drug unresponsiveness in patients with visceral leishmaniasis (vl) is a problem in many endemic areas. this study aimed to determine genetic diversity of leishmania donovani isolates from a vl endemic area in sudan as a possible explanation for drug unresponsiveness in some patients. thirty clinically stibogluconate (ssg)-sensitive isolates were made ssg-unresponsive in vitro by gradually increasing ssg concentrations. the sensitive isolates and their ssg-unresponsive counterparts were typed usi ...201020346944
risk factors of visceral leishmaniasis in east africa: a case-control study in pokot territory of kenya and uganda.in east africa, visceral leishmaniasis (vl) is endemic in parts of sudan, ethiopia, somalia, kenya and uganda. it is caused by leishmania donovani and transmitted by the sandfly vector phlebotomus martini. in the pokot focus, reaching from western kenya into eastern uganda, formulation of a prevention strategy has been hindered by the lack of knowledge on vl risk factors as well as by lack of support from health sector donors. the present study was conducted to establish the necessary evidence-b ...200818184669
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