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1.
BackgroundVisceral leishmaniasis (VL) in HIV-positive individuals is a global health problem. HIV-Leishmania coinfection worsens prognosis and mortality risk, and HIV-Leishmania coinfected individuals are more susceptible to VL relapses. Early initiation of antiretroviral therapy can protect against Leishmania infection in individuals living in VL-endemic areas, and regular use of antiretrovirals might prevent VL relapses in these individuals. We conducted a cross-sectional study in Petrolina, Brazil, an VL-endemic area, to estimate the prevalence of asymptomatic Leishmania cases among HIV-positive outpatients.MethodsWe invited any HIV-positive patients, aged ≥ 18-years-old, under antiretroviral therapy, and who were asymptomatic for VL. Patients were tested for Leishmania with enzyme-linked immunosorbent assays (ELISA)-rK39, immunochromatographic test (ICT)-rK39, direct agglutination test (DAT), latex agglutination test (KAtex), and conventional polymerase chain reaction (PCR). HIV-Leishmania coinfection was diagnosed when at least one VL test was positive.ResultsA total of 483 patients were included. The sample was predominantly composed of single, < 48-years-old, black/pardo, heterosexual males, with fewer than 8 years of schooling. The prevalence of asymptomatic HIV-Leishmania coinfection was 9.11% (44/483). HIV mono-infected and HIV-Leishmania coinfected groups differed statistically significantly in terms of race (p = 0.045), marital status (p = 0.030), and HIV viral load (p = 0.046). Black/pardo patients, married patients, and those with an HIV viral load up to 100,000 copies/ml presented higher odds for HIV-Leishmania coinfection.ConclusionsA considerable number of asymptomatic Leishmania cases were observed among HIV-positive individuals in a VL-endemic area. Given the potential impact on transmission and health costs, as well as the impact on these coinfected individuals, studies of asymptomatic Leishmania carriers can be useful for guiding public health policies in VL-endemic areas aiming to control and eliminate the disease.  相似文献   

2.
The effects of human immunodeficiency virus (HIV) on the immune response in patients with cutaneous leishmaniasis have not yet been fully delineated. This study quantified and evaluated the function of memory T-cell subsets in response to soluble Leishmania antigens (SLA) from patients coinfected with HIV and Leishmania with tegumentary leishmaniasis (TL). Eight TL/HIV coinfected subjects and 10 HIV seronegative subjects with TL were evaluated. The proliferative response of CD4+and CD8+T-cells and naïve, central memory (CM) and effector memory (EM) CD4+T-cells in response to SLA were quantified using flow cytometry. The median cell division indices for CD4+and CD8+T-cells of coinfected patients in response to SLA were significantly lower than those in patients with Leishmania monoinfection (p < 0.05). The proportions of CM and EM CD4+T-cells in response to SLA were similar between the coinfected patients and patients with Leishmania monoinfection. However, the median CM and EM CD4+T-cell counts from coinfected patients were significantly lower (p < 0.05). The reduction in the lymphoproliferative response to Leishmania antigens coincides with the decrease in the absolute numbers of both EM and CM CD4+T-cells in response to Leishmania antigens in patients coinfected with HIV/Leishmania.  相似文献   

3.
BackgroundVisceral leishmaniasis (VL) is an emerging condition affecting HIV-infected patients living in Latin America, particularly in Brazil. Leishmania-HIV coinfection represents a challenging diagnosis because the clinical picture of VL is similar to that of other disseminated opportunistic diseases. Additionally, coinfection is related to treatment failure, relapse and high mortality.ObjectiveTo assess the clinical-laboratory profile and outcomes of VL-HIV-coinfected patients using a group of non HIV-infected patients diagnosed with VL during the same period as a comparator.MethodsThe study was conducted at a reference center for infectious diseases in Brazil. All patients with suspected VL were evaluated in an ongoing cohort study. Confirmed cases were divided into two groups: with and without HIV coinfection. Patients were treated according to the current guidelines of the Ministry of Health of Brazil, which considers antimony as the first-choice therapy for non HIV-infected patients and recommends amphotericin B for HIV-infected patients. After treatment, all patients with CD4 counts below 350 cells/mm3 received secondary prophylaxis with amphotericin B.ResultsBetween 2011 and 2013, 168 patients with suspected VL were evaluated, of whom 90 were confirmed to have VL. In total, 51% were HIV coinfected patients (46 patients). HIV-infected patients had a lower rate of fever and splenomegaly compared with immunocompetent patients. The VL relapse rate in 6 months was 37% among HIV-infected patients, despite receiving secondary prophylaxis. The overall case-fatality rate was 6.6% (4 deaths in the HIV-infected group versus 2 deaths in the non HIV-infected group). The main risk factors for a poor outcome at 6 months after the end of treatment were HIV infection, bleeding and a previous VL episode.ConclusionAlthough VL mortality rates among HIV-infected individuals are close to those observed among immunocompetent patients treated with amphotericin B, HIV coinfection is related to a low clinical response and high relapse rates within 6 months.  相似文献   

4.

Background

Hepatitis C virus (HCV) coinfection was reported to negatively affect HIV disease and HIV infection has a deleterious effect on HCV-related liver disease. However, despite common occurrence of HCV/HIV coinfection little is known about the mechanisms of interactions between the two viruses.

Methods

We studied CD4+ and CD8+ T cell and CD19+ B cell apoptosis in 104 HIV-positive patients (56 were also HCV-positive) and in 22 HCV/HIV-coinfected patients treated for chronic hepatitis C with pegylated interferon and ribavirin. We also analyzed HCV/HIV coinfection in a Daudi B-cell line expressing CD4 and susceptible to both HCV and HIV infection. Apoptosis was measured by AnnexinV staining.

Results

HCV/HIV coinfected patients had lower CD4+ and CD8+ T cell apoptosis and higher CD19+ B cell apoptosis than those with HIV monoinfection. Furthermore, anti-HCV treatment of HCV/HIV coinfected patients was followed by an increase of CD4+ and CD8+ T cell apoptosis and a decrease of CD19+ B cell apoptosis. In the Daudi CD4+ cell line, presence of HCV infection facilitated HIV replication, however, decreased the rate of HIV-related cell death.

Conclusion

In HCV/HIV coinfected patients T-cells were found to be destroyed at a slower rate than in HIV monoinfected patients. These results suggest that HCV is a molecular-level determinant in HIV disease.  相似文献   

5.
Visceral leishmaniasis (VL) is an endemic zoonotic disease in Latin America caused by Leishmania (Leishmania) infantum, which is transmitted by sand flies from the genus Lutzomyia. VL occurs in 12 countries of Latin America, with 96% of cases reported in Brazil. Recently, an increase in VL, primarily affecting children and young adults, has been observed in urban areas of Latin America. The area in which this spread of VL is occurring overlaps regions with individuals living with HIV, the number of whom is estimated to be 1.4 million people by the World Health Organization. This overlap is suggested to be a leading cause of the increased number of reported VL-HIV coinfections. The clinical progression of HIV and L. infantum infections are both highly dependent on the specific immune response of an individual. Furthermore, the impact on the immune system caused by either pathogen and by VL-HIV coinfection can contribute to an accelerated progression of the diseases. Clinical presentation of VL in HIV positive patients is similar to patients without HIV, with symptoms characterized by fever, splenomegaly, and hepatomegaly, but diarrhea appears to be more common in coinfected patients. In addition, VL relapses are higher in coinfected patients, affecting 10% to 56.5% of cases and with a lethality ranging from 8.7% to 23.5% in Latin America, depending on the study. With regards to the diagnosis of VL, parasitological tests of bone marrow aspirates have proven to be the most sensitive test in HIV-infected patients. Serologic tests have demonstrated a variable sensitivity according to the method and antigens used, with the standard tests used for diagnosing VL in Latin America displaying lower sensitivity. For this review, few articles were identified that related to VL-HIV coinfections and originated from Latin America, highlighting the need for improving research within the regions most greatly affected. We strongly support the formation of a Latin American network for coinfections of Leishmania and HIV to improve the consistency of research on the current situation of VL-HIV coinfections. Such a network would improve the collection of vital data and samples for better understanding of the clinical manifestations and immunopathogenic aspects of VL in immunosuppressed patients. Ultimately, a concerted effort would improve trials for new diagnostic methodologies and therapeutics, which could accelerate the implementation of more specific and effective diagnosis as well as public policies for treatments to reduce the impact of VL-HIV coinfections on the Latin American population.  相似文献   

6.
In this work, we have found an antiproliferative effect on Leishmania sp. promastigotes and axenic amastigotes by the human immunodeficiency virus (HIV) aspartyl-proteinase inhibitors, Ac-Leu-Val-Phenylalaninal, Saquinavir mesylate and Nelfinavir, the latter two being used as part of antiretroviral therapy. This effect appears to be the result of cell division blockage. In addition, these drugs induced in culture a decrease in the percentage of co-infected HIV/Leishmania monocytes and amastigotes of Leishmania per macrophage. The finding of a dose-dependent inhibition of Leishmania promastigotes aspartyl-proteinase activity by these drugs allows us to propose this activity as the drug parasite target. A direct action of these HIV aspartyl-proteinase inhibitors on the parasite, would be correlated with the effect that highly active antiretroviral therapy have had in the decrease of HIV/Leishmania coinfection, opening an interesting perspective for new drugs research development based on this novel parasite proteinase family.  相似文献   

7.
8.
BackgroundDecreased hepatitis C virus (HCV) clearance, faster cirrhosis progression and higher HCV RNA levels are associated with Human Immunodeficiency virus (HIV) coinfection. The CD4+ T helper cytokines interleukin (IL)-21 and IL-17A are associated with virus control and inflammation, respectively, both important in HCV and HIV disease progression. Here, we examined how antigen-specific production of these cytokines during HCV mono and HIV/HCV coinfection was associated with HCV virus control.MethodsWe measured HCV-specific IL-21 and IL-17A production by transwell cytokine secretion assay in PBMCs from monoinfected and coinfected individuals. Viral control was determined by plasma HCV RNA levels.ResultsIn acutely infected individuals, those able to establish transient/complete HCV viral control tended to have stronger HCV-specific IL-21-production than non-controllers. HCV-specific IL-21 production also correlated with HCV viral decline in acute infection. Significantly stronger HCV-specific IL-21 production was detected in HAART-treated coinfected individuals. HCV-specific IL-17A production was not associated with lower plasma HCV RNA levels in acute or chronic HCV infection and responses were stronger in HIV coinfection. HCV-specific IL-21/ IL-17A responses did not correlate with microbial translocation or fibrosis. Exogenous IL-21 treatment of HCV-specific CD8+ T cells from monoinfected individuals enhanced their function although CD8+ T cells from coinfected individuals were somewhat refractory to the effects of IL-21.ConclusionsThese data show that HCV-specific IL-21 and IL-17A-producing T cells are induced in HIV/HCV coinfection. In early HIV/HCV coinfection, IL-21 may contribute to viral control, and may represent a novel tool to enhance acute HCV clearance in HIV/HCV coinfected individuals.  相似文献   

9.

Background

Visceral leishmaniasis has now emerged as an important opportunistic disease in patients coinfected with human immunodeficiency virus type-1 (HIV-1). Although the effectiveness of HIV-1 protease inhibitors, such as nelfinavir, in antiretroviral therapies is well documented, little is known of the impact of these drugs on Leishmania in coinfected individuals.

Methodology and Principal Findings

Here, we show that nelfinavir generates oxidative stress in the parasite, leading to altered physiological parameters such as an increase in the sub-G1 DNA content, nuclear DNA fragmentation and loss of mitochondrial potential, which are all characteristics of apoptosis. Pretreatment of axenic amastigotes with the caspase inhibitor z-VAD-fmk did not inhibit the increase in sub-G1 DNA content in nelfinavir-treated parasites, suggesting therefore that this antiviral agent does not kill Leishmania amastigotes in a caspase-dependent manner. Furthermore, we observed that the mitochondrial resident protein endonuclease G is involved. We also demonstrate that parasites overexpressing GSH1 (the rate limiting enzyme of glutathione biosynthesis) were more resistant to nelfinavir when compared to untransfected controls.

Conclusions and Significance

These data suggest that nelfinavir induces oxidative stress in Leishmania amastigotes, culminating in caspase-independent apoptosis, in which DNA is degraded by endonuclease G. This study provides a rationale for future, long-term design of new therapeutic strategies to test nelfinavir as a potential antileishmanial agent as well as for possible future use in Leishmania/HIV-1 coinfections.  相似文献   

10.
BackgroundIntroduction of combined antiretroviral therapy (cART) has improved survival of HIV infected individuals, while the relative contribution of liver-related mortality increased. Especially in HIV/HCV-coinfected patients hepatic fibrosis and portal hypertension represent the main causes of liver-related morbidity and mortality. Circulating miRNA-122 levels are elevated in HIV patients and have been shown to correlate with severity of liver injury. However, the association of miRNA-122 levels and hepatic fibrosis and portal hypertension remains to be explored in HIV/HCV coinfection.MethodsFrom a total of 74 (31% female) patients with HIV/HCV coinfection were included. Serum levels of miRNA-122 were analyzed by quantitative polymerase chain reaction (PCR) and normalized to SV-40 spike-in RNA. Hepatic venous pressure gradient (HVPG) was measured in 52 (70%) patients and the fibrosis stage was determined in 63 (85%) patients using transient elastography.ResultsThe levels of circulating miRNA-122 were increased in HIV/HCV coinfected patients and significantly correlated with the alanine aminotransferase (ALT) (rs = 0.438; p<0.001) and aspartate transaminase AST values (rs = 0.336; p = 0.003), but not with fibrosis stage (p = n.s.). Interestingly, miRNA-122 levels showed an inverse correlation with hepatic venous pressure gradient (HVPG) (rs = −0.302; p = 0.03).ConclusionElevated miRNA-122 levels are associated with liver injury, and with low HVPG. Though, miRNA-122 levels are not suitable to predict the degree of fibrosis, they might function as indicators for portal hypertension in HIV/HCV coinfected patients.  相似文献   

11.

Background

Host genetic factors such as MBL2 gene polymorphisms cause defects in the polymerization of MBL protein and result in a functional deficiency and/or in low serum levels that can influence susceptibility to various viral infections. The aim of this study was to estimate the frequency of alleles, genotypes and haplotypes related to -550, -221 and exon 1 polymorphisms of the MBL2 gene and investigate their association with HHV-8 in people living with HIV/AIDS (PLWHA), as well as the impacts on CD4 cell count and HIV viral load in HIV/HHV-8 coinfected and HIV monoinfected patients.

Results

A cross sectional study in PLWHA, with and without HHV-8 infection, exploring associations between different factors, was performed in the outpatient infectious and parasitic diseases clinic at a referral hospital. Genomic DNA extractions from leukocytes were performed using a commercial Wizard® Genomic DNA Purification kit (Promega, Madison, WI). The promoter region (-550 and -221) was genotyped with the TaqMan system (Applied TaqMan Biosystems® genotyping Assays), and the structural region (exon1) was genotyped with Express Sybr Greener Supermix kit (Invitrogen, USA). In total, 124 HIV/HHV-8 coinfected and 213 HIV monoinfected patients were analysed. Median TCD4 counts were significantly lower in HIV/HHV-8 coinfected patients, whereas the mean of the first and last viral load of HIV did not present significant difference. There was no difference in frequency between the LL, YY and AA genotypes between the HIV/HHV-8 coinfected or HIV monoinfected patients. However, in a multivariate analysis, coinfected patients with the intermediate expression haplotype of the MBL2 gene had an odds ratio of 3.1-fold (CI?=?1.2–7.6) of their last CD4 cell count being below 350 cells/mm3. Among the coinfected individuals, four developed KS and presented the intermediate expression MBL haplotype, with three being HYA/LXA and one being LYA/LYO.

Conclusions

Host genetic factors, such as -550, -221 and exon 1 polymorphisms, can be related to the may modify coinfections and/or to the development clinical manifestations caused by HHV-8, especially in HIV/HHV-8 coinfected patients who present the intermediate expression haplotypes of MBL.
  相似文献   

12.
The HAART therapy has improved life expectancy enabling long latency conditions caused by the hepatitis viruses that became the leading cause of death in HIV infected patients. In this study a group of 300 patients aged from 18 to 63 years were selected in order to assess the prevalence and consequences of HIV and the hepatitis B (HBV), C (HCV) and D (HDV) viruses coinfections. Study groups were designed for each coinfection. These groups were in turn divided in case groups formed of coinfected participants and control groups consisting of mono-infected participants. This classification was obtained by testing the participants for the presence of specific infection markers using the ELISA technique. As a result, in regard to the HIV/HBV coinfection the study group consisted of 16 coinfected participants and 114 HBV-infected participants resulting in a prevalence of the coinfection of 14%. In the case of the HIV/HDV coinfection the study group consisted of 5 coinfected participants and 45 HDV-infected participants. The prevalence of the HIV/HCV coinfection was 25% out of the 170 HCV-infected participants. The effect of the coinfections on the expression and levels of the infection markers was analyzed in constrast to those encountered in the case of the mono-infection. The observed changes in the expression of the specific hepatitis markers indicate the impact of the coinfection with HIV on the progression of the hepatitis infections. In addition, the inadequate immune response towards the hepatitis viruses in the case of the coinfected participants leads to the development of cirrhosis and end stage liver disease.  相似文献   

13.
Diagnostic tests for visceral leishmaniasis that are based on antigens of a single Leishmania strain can have low diagnostic performance in regions where heterologous parasites predominate. The aim of this study was to investigate and compare the performance of five serological tests, based on different Leishmania antigens, in three endemic countries for visceral leishmaniasis. A total number of 231 sera of symptomatic and asymptomatic cases and controls from three endemic regions of visceral leishmaniasis in East Sudan, North India and South France were evaluated by following serological tests: rKLO8- and rK39 ELISA, DAT (ITMA-DAT) and two rapid tests of rK39 (IT LEISH) and rKE16 (Signal-KA). Overall, rKLO8- and rK39 ELISA were most sensitive in immunocompetent patients from all endemic regions (96–100%) and the sensitivity was reduced to 81.8% in HIV co-infected patients from France. Sera of patients from India demonstrated significantly higher antibody responses to rKLO8 and rK39 compared with sera from Sudan (p<0.0001) and France (p<0.0037). Further, some Indian and Sudanese patients reacted better with rKLO8 than rK39. Sensitivity of DAT (ITMA-DAT) was high in Sudan (94%) and India (92.3%) but low in France being 88.5% and 54.5% for VL and VL/HIV patients, respectively. In contrast, rapid tests displayed high sensitivity only in patients from India (96.2%) but not Sudan (64–88%) and France (73.1–88.5% and 63.6–81.8% in VL and VL/HIV patients, respectively). While the sensitivity varied, all tests showed high specificity in Sudan (96.7–100%) and India (96.6%).Heterogeneity of Leishmania parasites which is common in many endemic regions complicates the diagnosis of visceral leishmaniasis. Therefore, tests based on homologous Leishmania antigens are required for particular endemic regions to detect cases which are difficult to be diagnosed with currently available tests.  相似文献   

14.
Leishmaniasis is caused by protozoa of the genus Leishmania and transmitted by sand flies from mammalian reservoirs to humans. In recent years, a northward spread of L. infantum from highly endemic Mediterranean countries into previously non-endemic Central European areas has been suspected based on presumed sporadic cases of autochthonous leishmaniasis. Here, we investigated whether sand flies are prevalent in Bavaria in Southern Germany, a federal state in which autochthonous cases have previously been reported. Considering the present and future climatic conditions, we determined whether Bavaria is suitable for five sand fly species with assumed spreading tendencies towards Central Europe: Phlebotomus ariasi, P. neglectus, P. perfiliewi and P. perniciosus that are known vectors for Leishmania in Europe, and P. mascittii, a suspected but not proven vector. Within Bavaria we defined sampling regions based on their climatic suitability and their spatial distance to the sites of the autochthonous cases and/or to areas of reported sand fly detection in states adjacent to Bavaria. At 155 locations in 7 sampling regions, CDC light traps were placed during 38 nights in the summers of 2009 and 2010, resulting in 202 trap-nights. All traps were negative for sand flies. The results suggest that Bavaria is not yet endemic for sand flies, but do not exclude the possibility of sporadic cases of autochthonous human or zoonotic Leishmania infections. This study, which combined methodological approaches from different disciplines, serves as reference for future surveys and risk analyses of sand flies and leishmaniasis in so far non-endemic areas of Europe.  相似文献   

15.

Background

Reactivation of chronic Chagas disease, which occurs in approximately 20% of patients coinfected with HIV/Trypanosoma cruzi (T. cruzi), is commonly characterized by severe meningoencephalitis and myocarditis. The use of quantitative molecular tests to monitor Chagas disease reactivation was analyzed.

Methodology

Polymerase chain reaction (PCR) of kDNA sequences, competitive (C-) PCR and real-time quantitative (q) PCR were compared with blood cultures and xenodiagnosis in samples from 91 patients (57 patients with chronic Chagas disease and 34 with HIV/T. cruzi coinfection), of whom 5 had reactivation of Chagas disease and 29 did not.

Principal Findings

qRT-PCR showed significant differences between groups; the highest parasitemia was observed in patients infected with HIV/T. cruzi with Chagas disease reactivation (median 1428.90 T. cruzi/mL), followed by patients with HIV/T. cruzi infection without reactivation (median 1.57 T. cruzi/mL) and patients with Chagas disease without HIV (median 0.00 T. cruzi/mL). Spearman''s correlation coefficient showed that xenodiagnosis was correlated with blood culture, C-PCR and qRT-PCR. A stronger Spearman correlation index was found between C-PCR and qRT-PCR, the number of parasites and the HIV viral load, expressed as the number of CD4+ cells or the CD4+/CD8+ ratio.

Conclusions

qRT-PCR distinguished the groups of HIV/T. cruzi coinfected patients with and without reactivation. Therefore, this new method of qRT-PCR is proposed as a tool for prospective studies to analyze the importance of parasitemia (persistent and/or increased) as a criterion for recommending pre-emptive therapy in patients with chronic Chagas disease with HIV infection or immunosuppression. As seen in this study, an increase in HIV viral load and decreases in the number of CD4+ cells/mm3 and the CD4+/CD8+ ratio were identified as cofactors for increased parasitemia that can be used to target the introduction of early, pre-emptive therapy.  相似文献   

16.
BackgroundHIV and tuberculosis (TB) coinfection remains a major public health threat in sub-Saharan Africa. Integration and decentralization of HIV and TB treatment services are being implemented, but data on outcomes of this strategy are lacking in rural, resource-limited settings. We evaluated TB treatment outcomes in TB/HIV coinfected patients in an integrated and decentralized system in rural KwaZulu-Natal, South Africa.MethodsWe retrospectively studied a cohort of HIV/TB coinfected patients initiating treatment for drug-susceptible TB at a district hospital HIV clinic from January 2012-June 2013. Patients were eligible for down-referral to primary health clinics(PHCs) for TB treatment completion if they met specific clinical criteria. Records were reviewed for patients’ demographic, baseline clinical and laboratory information, past HIV and TB history, and TB treatment outcomes.ResultsOf 657(88.7%) patients, 322(49.0%) were female, 558(84.9%) were new TB cases, and 572(87.1%) had pulmonary TB. After TB treatment initiation, 280(42.6%) were down-referred from the district level HIV clinic to PHCs for treatment completion; 377(57.4%) remained at the district hospital. Retained patients possessed characteristics indicative of more severe disease. In total, 540(82.2%) patients experienced treatment success, 69(10.5%) died, and 46(7.0%) defaulted. Down-referred patients experienced higher treatment success, and lower mortality, but were more likely to default, primarily at the time of transfer to PHC.ConclusionDecentralization of TB treatment to the primary care level is feasible in rural South Africa. Treatment outcomes are favorable when patients are carefully chosen for down-referral. Higher mortality in retained patients reflects increased baseline disease severity while higher default among down-referred patients reflects failed linkage of care. Better linkage mechanisms are needed including improved identification of potential defaulters, increased patient education, active communication between hospitals and PHCs, and tracing of patients lost to follow up. Decentralized and integrated care is successful for carefully selected TB/HIV coinfected patients and should be expanded.  相似文献   

17.
Viral and parasitic coinfections are known to lead to both enhanced disease progression and altered disease states. HTLV-1 and Strongyloides stercoralis are co-endemic throughout much of their worldwide ranges resulting in a significant incidence of coinfection. Independently, HTLV-1 induces a Th1 response and S. stercoralis infection induces a Th2 response. However, coinfection with the two pathogens has been associated with the development of S. stercoralis hyperinfection and an alteration of the Th1/Th2 balance. In this study, a model of HTLV-1 and S. stercoralis coinfection in CD34+ umbilical cord blood hematopoietic stem cell engrafted humanized mice was established. An increased level of mortality was observed in the HTLV-1 and coinfected animals when compared to the S. stercoralis infected group. The mortality was not correlated with proviral loads or total viral RNA. Analysis of cytokine profiles showed a distinct shift towards Th1 responses in HTLV-1 infected animals, a shift towards Th2 cytokines in S. stercoralis infected animals and elevated TNF-α responses in coinfected animals. HTLV-1 infected and coinfection groups showed a significant, yet non-clonal expansion of the CD4+CD25+ T-cell population. Numbers of worms in the coinfection group did not differ from those of the S. stercoralis infected group and no autoinfective larvae were found. However, infective larvae recovered from the coinfection group showed an enhancement in growth, as was seen in mice with S. stercoralis hyperinfection caused by treatment with steroids. Humanized mice coinfected with S. stercoralis and HTLV-1 demonstrate features associated with human infection with these pathogens and provide a unique opportunity to study the interaction between these two infections in vivo in the context of human immune cells.  相似文献   

18.
Chronic hepatitis C virus (HCV) infection is associated with increased levels of peripheral T cell apoptosis. We aimed to study whether T cell apoptosis markers indicate pathways that may contribute to clinical progression in HCV monoinfected and HIV–HCV coinfected patients. Activation of the extrinsic apoptosis pathways was measured by levels of death receptor Fas, initiator caspase 8 and effector caspases 3 and 7 activity and Annexin V binding on peripheral CD4 and CD8 T cells of HCV monoinfected and HIV/HCV coinfected patients, as well as healthy controls and HIV-infected, hepatitis B virus-infected and primary biliary cirrhosis disease controls. Association with liver fibrosis was assessed by biopsy or by transient elastography. HCV monoinfected and HIV–HCV coinfected patients displayed enhanced peripheral CD4 and CD8 T cell apoptosis. Caspase 8 activity was highest in HIV–HCV coinfection, without enhanced downstream activity of caspases 3 and 7. Level of peripheral T cell apoptosis was independent of liver fibrosis or other disease parameters in all disease groups. The extrinsic apoptosis pathway is upregulated in HCV monoinfection and HIV–HCV coinfection, but this is independent of liver disease severity.  相似文献   

19.
Leishmaniasis is a vector borne disease caused by protozoa of the genus Leishmania. Human leishmaniasis is not endemic in Australia though imported cases are regularly encountered. This study aimed to provide an update on the molecular epidemiology of imported leishmaniasis in Australia. Of a total of 206 biopsies and bone marrow specimens submitted to St Vincent’s Hospital Sydney for leishmaniasis diagnosis by PCR, 55 were found to be positive for Leishmania DNA. All PCR products were subjected to restriction fragment length polymorphism analysis for identification of the causative species. Five Leishmania species/species complexes were identified with Leishmania tropica being the most common (30/55). Travel or prior residence in a Leishmania endemic region was the most common route of acquisition with ~47% of patients having lived in or travelled to Afghanistan. Cutaneous leishmaniasis was the most common manifestation (94%) with only 3 cases of visceral leishmaniasis and no cases of mucocutaneous leishmaniasis encountered. This report indicates that imported leishmaniasis is becoming increasingly common in Australia due to an increase in global travel and immigration. As such, Australian clinicians must be made aware of this trend and consider leishmaniasis in patients with suspicious symptoms and a history of travel in endemic areas. This study also discusses the recent identification of a unique Leishmania species found in native kangaroos and a potential vector host which could create the opportunity for the establishment of a local transmission cycle within humans.  相似文献   

20.

Background

Leishmania (Viannia) braziliensis is a parasite recognized as the most important etiologic agent of mucosal leishmaniasis (ML) in the New World. In Amazonia, seven different species of Leishmania, etiologic agents of human Cutaneous Leishmaniasis, have been described. Isolated cases of ML have been described for several different species of Leishmania: L. (V.) panamensis, L. (V.) guyanensis and L. (L.) amazonensis.

Methodology

Leishmania species were characterized by polymerase chain reaction (PCR) of tissues taken from mucosal biopsies of Amazonian patients who were diagnosed with ML and treated at the Tropical Medicine Foundation of Amazonas (FMTAM) in Manaus, Amazonas state, Brazil. Samples were obtained retrospectively from the pathology laboratory and prospectively from patients attending the aforementioned tertiary care unit.

Results

This study reports 46 cases of ML along with their geographical origin, 30 cases caused by L. (V.) braziliensis and 16 cases by L. (V.) guyanensis. This is the first record of ML cases in 16 different municipalities in the state of Amazonas and of simultaneous detection of both species in 4 municipalities of this state. It is also the first record of ML caused by L. (V.) guyanensis in the states of Pará, Acre, and Rondônia and cases of ML caused by L. (V.) braziliensis in the state of Rondônia.

Conclusions/Significance

L. (V.) braziliensis is the predominant species that causes ML in the Amazon region. However, contrary to previous studies, L. (V.) guyanensis is also a significant causative agent of ML within the region. The clinical and epidemiological expression of ML in the Manaus region is similar to the rest of the country, although the majority of ML cases are found south of the Amazon River.

Author Summary

Leishmaniasis is considered a neglected disease with 1.5 million new cases of cutaneous leishmaniasis (CL) occurring each year. In the Amazon region and in the Americas in general, ML is caused by Leishmania (Viannia) braziliensis, though in rare cases it has been related to other species. ML, which is associated with inadequate treatment of CL, normally manifests itself years after the occurrence of CL. Clinical features evolve slowly and most often affect the nasal cavity, in some cases causing perforation, or even destruction, of the septum. Diagnosis is made using the Montenegro skin test, serology and histopathology of the patients'' mucosal tissues, or by isolation of the parasites. PCR is the best way to identify the species of leishmaniasis and is therefore the diagnostic method of choice. This paper describes 46 cases of ML and their geographical origin, 30 cases associated with L. (V.) braziliensis and 16 with L. (V.) guyanensis. The species of leishmaniasis was identified using mucosal biopsies taken from Amazonian patients who were diagnosed and treated for ML in the tertiary care unit, in Manaus, Amazonas state, Brazil. This is the highest number of ML cases caused by L. (V.) guyanensis that has ever been reported.  相似文献   

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