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1.
IntroductionCutaneous leishmaniasis (CL) is one of wobbling endemic disease in Iraq, that cause intracellular obligate protistan parasite returned to the genusLeishmania. This study is aimed to identify epidemiology of CL, detect the prevalence of Leishmania tropica and find the phylogenetic relationship.MethodologyThe current study was conducted in the main hospitals of Thi-Qar province-south of Iraq for period from November 2018 to October 2019. Nested-PCR was used to amplify kinetoplast minicircle fragments DNA.ResultsIt was recorded 247 clinical cases with CL, the infections of males were higher than females, while infection rate appeared gradual reduction with age progress. Furthermore, the most CL infections were as single lesions and occurred in December. The infections of upper limbs were high when compared with other body regions. The molecular diagnosis showed L. tropica was more frequently. DNA sequences of kDNA gene of L. tropica showed confirmative genetic detection of local isolates using NCBI-Blast data and phylogenetic tree analysis after comparison with global recorded isolates. The local L. tropica isolates showed genetically closed related to NCBI-Blast L. tropica with accession number AB678350.1. Generally, the analysis of kDNA nitrogen bases sequences showed that all of samples were consistent with those recorded at the NCBI.ConclusionThe kDNA minicircle sequences analysis results showed mismatching of the local isolates decrease whenever approached from the Iranian border. In addition, genetic heterogeneity diagnosis is important for detection of therapy, control and epidemiological studies.  相似文献   

2.
Infection of equids by Leishmania (L.) parasites was previously described in both the Old and New World, particularly in Central and South America. Equine cutaneous leishmaniasis (CL) is caused by the Leishmania species, L. Viannia (V.) braziliensis and L. infantum, previously identified in humans and other parasite hosts living in the same geographic endemic areas. Sporadic autochthonous clinical cases, with no travel history, were documented in several countries including Germany, Portugal, Spain, Texas and Brazil; L. infantum and L. (Mundinia) martiniquensis were the infectious species. Prevalence of subclinical infections is extremely low and CL is observed in only a small proportion of infected animals with the appearance of single or multiple cutaneous lesions located on the head, external ear, scrotum, legs and the neck. To date, there has been no report of visceral abnormalities. However, the mild clinical profile of the disease and its spontaneous regression may indicate that skin lesions related to Leishmania infection is underdiagnosed. Importantly, although the prevalence of Leishmania infections in the equine population is low, a risk may rise from its potential involvement in the parasite transmission cycles as a source of infection for phlebotomine vectors and susceptible mammalian hosts. This review article summarises our current knowledge of the epidemiology, clinical presentation and diagnosis of Leishmania-infected equids.  相似文献   

3.
Leishmania spp. are polarized single-celled eukaryotic parasites, the perpetuation of which relies on two other organisms they “use” as hosts. One of the Leishmania host organisms is a blood-feeding female sand fly, the second host being a mammal that acts as a blood source for the female sand fly. Leishmania-hosting sand flies transmit the metacyclic promastigote developmental stage to the mammal skin. While many mammals are known to act as sand fly blood sources, only some of these mammals are/will be “used” as Leishmania hosts. This host status means that skin as well as skin-distant tissues and cell lineages (mononuclear phagocytes and fibroblasts) of these mammals are rapidly and continuously remodelled as niches where Leishmania will deploy its developmental programs: it is noteworthy that without the deployment of the developmental program underlying Leishmania transmission from the mammal to the blood-searching and blood-feeding sand flies, the perpetuation of Leishmania will be suspended. While post genomic approaches are providing insight about some features of Leishmania major, Leishmania infantum/chagasi and Leishmania braziliensis, such approaches are not yet available for the natural hosts (wild rodents, wild sand flies) these Leishmania species “use” as hosts.  相似文献   

4.
5.
An immunoenzymatic assay (ELISA), an indirect immunofluorescence antibody test (IFAT) with different antigens (ELISA-Leishmania chagasi, ELISA-L. major-like, IFAT-L. chagasi and IFAT-L. major-like), and an immunochromatographic test were assessed for the diagnosis of canine visceral leishmaniasis (CVL). Serum samples from 144 dogs from an endemic area for visceral leishmaniasis in the municipality of Rio de Janeiro were tested. The sensitivities of the serological tests were 93%, 100%, 73%, 60% and 93%, with specificities of 87%, 92%, 77%, 96% and 92% for the ELISA-L. major-like, ELISA-L. chagasi, IFAT-L. major-like, IFAT-L. chagasi and the immuno chromatographic test, respectively. ELISA-L. chagasi was the best test for the diagnosis of CVL, but the immunochromatographic test could be a useful alternative as it offers simple and rapid diagnosis without the need for a specialized laboratory.  相似文献   

6.
The use of non invasive sampling, such as collection of conjunctival swabs, as a diagnostic tool for the detection of Leishmania DNA is of interest. The purpose of this study was to evaluate the diagnostic utility of detecting Leishmania infection with the use of conjunctival swab samples in dogs living in a highly endemic area for leishmaniosis and to investigate, for the first time, the presence of Leishmania DNA in oral swabs in the same population. One hundred sixty-three dogs living outdoor and recruited in various provinces of Sicily were studied. Leishmania infantum indirect fluorescent antibody test (IFAT), delayed-type hypersensitivity reaction to leishmanin (DTH) and real-time PCR of blood (BL), lymph node (LN), conjunctival (CS) and oral swab (OS) samples were performed. The positive PCR percentages in LN, CS, OS and BL samples were: 24.5%, 22.1%, 8.7% and 5.5%, respectively. Serological and DTH positive percentages were 27.0% and 73.8%, respectively. Seropositive and LN-PCR positive dogs had a high likelihood to be positive by CS-PCR. The similar positive PCR percentages found in CS and LN samples suggest the use of CS-PCR as non-invasive alternative technique to LN-PCR for the detection of Leishmania infection in dogs. In addition, this study demonstrated, for the first time, the presence of Leishmania DNA in oral swabs in dogs.  相似文献   

7.
Leishmania infantum infection in wildlife is increasingly reported in Europe, but scant data are available in Italy so far. This study aimed to investigate the circulation of L. infantum among sylvatic hosts in Sicily (southern Italy), a highly endemic area for canine leishmaniosis, through serological and molecular tools. Target tissues (skin, spleen, lymph nodes) collected from 71 European rabbits, 2 European hares, 7 red foxes, 11 European wildcats and 1 pine marten, were qPCR analysed for the detection of L. infantum DNA. Additionally, 40 rabbits, older than one year, were serologically screened for specific anti-Leishmania antibodies. Leishmania infantum was molecularly diagnosed in 5.4% (n = 5) of the examined animals (3/71 European rabbits, 2/7 red foxes). In many of the qPCR positive animals (4/5), the parasite DNA was more prevalent in visceral than cutaneous tissues. None of the positive animal showed signs of disease and/or macroscopic alterations of organs; low parasitic burden in all positive tissue samples was also recorded. Only one rabbit serum (i.e., 2.5%) tested positive for anti-Leishmania antibodies. The seropositive rabbit was in good health status and no amastigotes were observed in lymph-node aspirate and blood smears.This study provides first evidence of L. infantum infection in wild animals from Sicily (southern Italy). Despite the low prevalence of infection here reported, the circulation of the Leishmania in wild reservoirs in Sicily remains worthy of future investigations for a better understanding of their role in the epidemiology of the disease as well as to fine-tune control strategies in the area.  相似文献   

8.
The aims of this study were to evaluate the immunomodulatory role of TGF-β1, IL-10, and INF-γ in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n = 15) and symptomatic (n = 15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-β1, IL-10, and INF-γ. Naturally active in vitro produced TGF-β1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-β1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-γ concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-γ is being produced in canine infection, mean levels of TGF-β1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2.  相似文献   

9.
Allometric scaling is widely used for the determination of first dosage regimen and the interpolation or extrapolation of pharmacokinetic parameters across many animal species during drug development. In this article, 85 drugs used in veterinary medicine obtained from the Food Animal Residue Avoidance Databank database were selected for allometric scaling analysis. Outlier species were identified by statistical methods. The results showed that 77% and 88% of drugs displayed significant correlations between total systemic clearance (CL) and volume of distribution at steady status (Vss) vs. body weight (< 0.05) on a log‐log scale, respectively. The distribution of the allometric exponent b for CL and Vss displays approximate normal distribution, with means (0.87 and 0.99) and standard deviations (0.143 and 0.157) for CL and Vss, respectively. Twelve drugs were identified to have at least one outlier species for CL and ten drugs for Vss. The human CL and Vss were predicted for selected drugs by the obtained allometric equations. The predicted CL and Vss were within a threefold error compared to observed values, except the predicted CL values for antipyrine, warfarin and diazepam. The results can be used to estimate cross‐species pharmacokinetic profiles for predicting drug dosages in veterinary species, and to identify those species for which interpolation or extrapolation of pharmacokinetics properties may be problematic.  相似文献   

10.
Canine leishmaniosis (CanL) caused by the parasite Leishmania infantum is a systemic disease with variable clinical signs. The disease is endemic in the Mediterranean countries and dogs are the main domestic reservoir of the parasite. The quite complicated immune response against the parasite is crucial for the evolution of CanL infection with the skin playing a major role in its immunopathogenesis.After the inoculation of Leishmania promastigotes into the dermis by sand fly bites, complement factors, Langerhan's cells, neutrophils, fibroblasts and keratinocytes are involved in the activation of the innate arm of the skin immune system, with the macrophages and dendritic cells to play a major key role.The effective activation of cellular immunity is the cornerstone of dog's resistance against the parasite. Promastigotes reaching the dermis are engulfed, processed and transferred by APCs to draining lymph nodes to stimulate naïve T-cells for proliferation and differentiation into armed effector T-cells. Th1 cells activate the infected macrophages to kill Leishmania, whereas Th2 cells divert the immune response to humoral immunity and down regulation of cellular immunity with Th1 cell anergy. Inhibition of co-stimulatory molecules expression by infected macrophages contributes to T-cell anergy. In canine subclinical infections cutaneous lymphocytic infiltrate and parasites are absent, as opposed to dogs with clinical leishmaniosis. CD8+ cells constitute a significant population of cellular immunity in CanL since they outnumber CD4+ cells in the dermis, producing IFN-γ in sub clinically infected dogs and high levels of IL-4 in dogs with clinical leishmaniosis.Numerous B-lymphocytes have been shown to heavily infiltrate the dermis at least in exfoliative dermatitis in CanL. A mixed Th1/Th2 cytokine profile has been found in the dermis of naturally infected with L. infantum dogs. In the skin of dogs with clinical leishmaniosis, where plasma cells outnumber T lymphocytes in the dermal infiltrate, there is an overproduction of IL-4, IL-13 and TNF-α leading to Th2-biased humoral immune response. The issue of humoral immunity polarization in CanL remains controversial. Much still needs to be learned about other mechanisms underlying the complex interaction between the skin immune system and the parasite.  相似文献   

11.
Two sibling foxhounds born to a Leishmania seropositive bitch were presented after testing seropositive for Leishmania. Leishmania infantum infection was detected via histopathology, culture, and quantitative polymerase chain reaction (q-PCR). This is the first report of natural infection with Leishmania infantum with the possibility for vertical transmission in North America.  相似文献   

12.

Background

Leishmania spp. are zoonotic protozoans that infect humans and other mammals such as dogs. The most significant causative species in dogs is L. infantum. In dogs, leishmaniosis is a potentially progressive, chronic disease with varying clinical outcomes. Autochthonous cases of canine leishmaniosis have not previously been reported in the Nordic countries.

Results

In this report we describe the first diagnosed autochthonous cases of canine leishmaniosis in Finland, in which transmission via a suitable arthropod vector was absent. Two Finnish boxers that had never been in endemic areas of Leishmania spp., had never received blood transfusions, nor were infested by ectoparasites were diagnosed with leishmaniosis. Another dog was found with elevated Leishmania antibodies. A fourth boxer dog that had been in Spain was considered to be the source of these infections. Transmission occurred through biting wounds and semen, however, transplacental infection in one of the dogs could not be ruled out.Two of the infected dogs developed a serious disease and were euthanized and sent for necropsy. The first one suffered from membranoproliferative glomerulonephritis and the second one had a chronic systemic disease. Leishmania sp. was detected from tissues by PCR and/or IHC in both dogs. The third infected dog was serologically positive for Leishmania sp. but remained free of clinical signs.

Conclusions

This case report shows that imported Leishmania-infected dogs may pose a risk for domestic dogs, even without suitable local arthropod vectors.  相似文献   

13.
Leishmania spp. are digenetic parasites whose infection occurs inside the mononuclear phagocitary system. The iron superoxide dismutase secreted (Fe-SODe) by promastigotes of Leishmania spp. seems to plays an important role in the defense to environmental detoxification and neutralization of oxidative stress damage caused by reactive oxygen species (ROS) produced by macrophages during the infection. Parasites Fe-SODe is involved in establishing the infection and manifestation of Leishmaniasis. Its high immunogenicity makes it a useful molecular marker in diagnosing trypanosomatids infections. The aim of this study is demonstrate that purified Fe-SODe from Leishmania infantum is much more sensitive than un-purified Fe-SODe for diagnosis canine Leishmaniasis. We have purified a Fe-SODe of L. infantum using an ion exchange and a molecular sieve chromatographies and its application in diagnosis of canine Leishmaniasis was tested. One hundred and forty-five dogs’ sera from Andalusia Autonomous Community, Spain were tested by ELISA and Western blot and the antigen Fe-SODe purified is compared with two different antigens: the total parasites soluble lysate and the unpurified Fe-SODe. To validate the results obtained using the Fe-SODe purified we tasted 10 L. infantum infected dogs’ sera from Lombardy, Italy as positive control.  相似文献   

14.
Leishmaniases are endemic in many countries, mainly in rural areas. In Brazil, Leishmania infection is responsible for many cases of Leishmaniases, including recent reports in urban regions. Despite their sensitivity, traditional serological and parasitological methods for detecting Leishmaniases have proven inadequate for species discrimination. This study aimed to identify Leishmania species in biological samples by a fast methodology, avoiding "in vitro" cultivation. Knowledge of the Leishmania species is an important tool in regions where both New World visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are prevalent. As these new foci appear in areas not traditionally endemic for VL, the main problem is to distinguish between true autochthonous infections and infections acquired in other well-known endemic areas. Since, domestic dogs are known to be the main VL and CL reservoir, they are regularly investigated in endemic areas to prevent, principally, severe and often fatal VL in humans. However, several infected dogs present no clinical signs or clinical signs similar to other canine diseases. Here, we evaluated the ability of PCR to diagnose VL and distinguish L. (L.) chagasi from other Leishmania species in domestic dogs. Samples from 114 dogs from 30 cities (Sao Paulo, Brazil) were divided into two groups: 44 symptomatic and 70 asymptomatic. They were assayed by parasitological methods (culture and microscopic examination) and PCR to determine L. (L.) chagasi, L. (V.) braziliensis; and in some cases, Leishmania spp. Parasitological tests and PCR-L. chagasi were concordant in 105 samples (92%). VL was confirmed in 49 dogs, while 56 had negative results. Of the 114 samples, 9 had discordant results, but were further tested by PCR-Leishmania spp. with positive results. VL was also confirmed in 4 dogs having negative parasitological tests and positive PCR-L. chagasi. Consequently, this PCR was positive for 100% (53/49) of dogs with parasites detected in parasitological tests. Also, PCR demonstrated high specificity detecting 61 dogs negative for VL. Leishmania infection was negative in 56 dogs, and 5 with positive culture and PCR-Leishmania spp. had CL since they were positive in PCR-L. braziliensis. This study shows the importance of including PCR in diagnosis of Leishmaniases by differential diagnosis contributing to the surveillance and control of VL programs.  相似文献   

15.
The Leishmania species present a genetic homology that ranges from 69 to 90%. Because of this homology, heterologous antigens have been used in the immunodiagnosis and vaccine development against Leishmania infections. In the current work, we describe the identification of species-specific and cross-reactive antigens among several New World Leishmania species, using symptomatic and asymptomatic naturally Leishmania chagasi-infected dog sera. Soluble antigens from five strains of New World Leishmania were separated by electrophoresis in SDS-PAGE and immunoblotted. Different proteins were uniquely recognized in the L. chagasi panel by either symptomatic or asymptomatic dog sera suggesting their use as markers for the progression of disease and diagnosis of the initial (sub-clinical) phase of the infection. Cross-reactive antigens were identified using heterologous antigenic panels (L. amazonensis strains PH8 and BH6, L. guyanensis and L. braziliensis). L. guyanensis panel showed the highest cross-reactivity against L. chagasi specific antibodies, suggesting that proteins from this extract might be suitable for the diagnosis of visceral canine leishmaniasis. Interestingly, the 51 and 97 kDa proteins of Leishmania were widely recognized (77.8% to 100%) among all antigenic panels tested, supporting their potential use for immunodiagnosis. Finally, we identified several leishmanial antigens that might be useful for routine diagnosis and seroepidemiological studies of the visceral canine leishmaniasis.  相似文献   

16.
Clinically available synthetic chemotherapeutics to treat the vector-borne protozoan infection, leishmaniasis, are associated with serious complications such as toxicity and emergence of resistance. Natural products from plants consist of interesting biomolecules that may interfere with DNA or membrane integrity of the parasite and can possibly minimise the associated side effects. In the present study, various fractions of Euphorbia wallichii (EW) root extracts including n-hexane (EWNX), ethyl acetate (EWEA), chloroform (EWCH) and aqueous (EWAQ), were evaluated for their antileishmanial potential against Leishmania tropica followed by investigation of the possible mechanism of action via reactive oxygen species (ROS) quantification, membrane permeability (via sytox green dye) and apoptotic assay (via AO/EB method) using fluorescent microscopy. Two of the fractions i.e. EWEA and EWAQ inhibited the growth of promastigotes (IC50 7.8 and 10.2 μg/mL, respectively) and amastigotes (IC50 9.9 and 13.3 μg/mL, respectively) forms almost at similar concentrations as found for the standard antileishmanial drugs, tartar emetic (TA) and Glucantime (IC50 9.4 and 21.5 μg/mL, respectively). Both the active fractions remained non-toxic towards human blood erythrocytes and were able to cause membrane permeability and apoptotic induction (using Triton X-100 as a positive control) leading to death of Leishmania parasites. However, both the fractions could not triger significant and persistent ROS generation, compared to hydrogen peroxide used as a positive control. Antilesihmanial activity of the two active fractions might be attributed to the presence of high quantity of tannins and saponins.  相似文献   

17.
Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of a widespread serious zoonotic disease that affects both humans and dogs. Prevalence and incidence of the canine infection are important parameters to determine the risk and the ways to control this reemergent zoonosis. Unfortunately, there is not a gold standard test for Leishmania infection. Our aim was to assess the operative validity of commercial tests used to detect antibodies to Leishmania in serum samples from experimental infections. Three ELISA tests (LEISCAN® Leishmania ELISA Test, INGEZIM® LEISHMANIA, and INGEZIM® LEISHMANIA VET), three immunochromatographic tests (INGEZIM® LEISHMACROM, SNAP® Leishmania, and WITNESS® Leishmania), and one IFAT were evaluated. LEISCAN® Leishmania ELISA test achieved the highest sensitivity and accuracy (both 0.98). Specificity was 1 for all tests except for IFAT. All tests but IFAT obtained a positive predictive value of 1, while the maximum negative predictive value was achieved by LEISCAN® Leishmania ELISA Test (0.93). The best positive likelihood ratio was obtained by INGEZIM® LEISHMANIA VET (30.26), while the best negative likelihood ratio was obtained by LEISCAN® Leishmania ELISA Test (0.02). The highest diagnostic odds ratio was achieved by LEISCAN® Leishmania ELISA Test (729.00). The largest area under the ROC curve was obtained by LEISCAN® Leishmania ELISA Test (0.981). Quantitative ELISA based tests performmed better than qualitative tests (“Rapid Tests”), and the test best suited to detect Leishmania in infected dogs and to provide clinically useful information was LEISCAN® Leishmania ELISA Test. This and other results point also to the need of revising the status of IFAT as a gold standard for the diagnosis of leishmaniasis.  相似文献   

18.
Leishmania spp. infection was investigated in tissue samples of wild carnivores from the Spanish Basque Country (BC), by PCR and DNA sequencing. The region is at the northern periphery of Leishmania infantum endemic Iberian Peninsula and infection in the dog (reservoir) or other species has not been previously reported. Leishmania kinetoplast DNA was detected by real-time PCR (rtPCR) in 28% (44/156) of animals. Specifically, in 26% of Eurasian badgers (n = 53), 29% of foxes (n = 48), 29% of stone martens (n = 21) and in 25–50% of less numerous species including genets, wild cats, pole cats, European mink and weasels. Infected animals particularly badgers, were most prevalent in the southernmost province of the BC (Araba) in areas dominated by arable land. Subsequent amplification and sequencing of a fragment of the rRNA internal transcribed spacer 2 (ITS2) from a subset of rtPCR positives samples confirmed the species as L. infantum, showing a high sequence homogeneity with ITS2 sequences of L. infantum from dogs and humans from southern Spain. In summary, this study reports for the first time L. infantum infection in wild carnivores from the BC including in stone martens, pole cats and minks in which infection has not been previously described. It supports the need to study infection in dogs and people in this region and is an example of the value of infection surveillance in wildlife to assess potential risks in the domestic environment and their role in spreading infections in non-endemic areas.  相似文献   

19.
20.
Sebaceous adenitis (SA) may be idiopathic (ISA) or associated with other disorders. The purpose of the present study was to compare the cutaneous histopathology of SA in cases in which Leishmania organisms were detected by immunohistochemistry (IHC) with that of cases diagnosed as ISA. Skin sections of 29 patients were evaluated histologically and divided into two groups, one characterized by several epidermal and subepidermal lesions, a granulomatous to pyogranulomatous nodular to diffuse dermatitis involving the sebaceous glands and a positive IHC for Leishmania spp. The other group was characterized by orthokeratotic hyperkeratosis, follicular keratosis with different degrees of pyogranulomatous to granulomatous SA, lack of nodular dermatitis and a negative IHC for Leishmania spp. Hidradenitis was present in both groups. From these results it can be concluded that SA in canine Leishmaniosis (CL) is usually present together with a nodular to diffuse dermal infiltrate and epidermal and subepidermal lesions, and that SA in the absence of dermal inflammation is probably not associated with or suggestive of CL, even in regions where the disease is endemic.  相似文献   

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