RESUMEN
When silica nanoparticles (SiNP) reach the water bodies interact with the already existing pollutants in the environments. This study aimed to evaluate the ecotoxicity of SiNP under the presence/absence of Cu in mosquitofish (Gambusia holbrooki). Fish were exposed to 0, 10 and 100 mg SiNP L-1, alone or mixed with Cu (0.25 mg L-1). After 96 h, the amount of colony forming units (CFU) of bacteria living on the skin mucus was analysed, and oxidative stress, tissue damage enzymes, and neurotoxicity were evaluated. We observed a reduction in CFU when Cu was present in the media. The liver was the target organ, evidencing a decrease in tissue damage enzymatic activities, activation of the antioxidant system in all treatments, and lipid oxidative damage when the SiNP and Cu were mixed. Overall, SiNP ecotoxicity was proved, which could also be enhanced by the presence of ubiquitous elements such as metals.
Asunto(s)
Ciprinodontiformes , Contaminantes Químicos del Agua , Animales , Cobre/toxicidad , Estrés Oxidativo , Antioxidantes , Ciprinodontiformes/fisiología , Contaminantes Químicos del Agua/toxicidadRESUMEN
Bothrops atrox snakebites are a relevant problem in the Amazon basin. In this biodiverse region, the ethnomedicinal approach plays an important role as an alternative to antivenom therapy. Urospatha sagittifolia (Araceae) is a plant used for this purpose; however, its neutralizing properties have not been scientifically accessed. To fill this gap, we investigated the ability of U. sagittifolia to modulate the catalytic activity of Bothrops atrox venom, and their toxic consequences, such as local damage and lethality. The venom profile of B. atrox was assessed by chromatography and electrophoresis. Inhibition of the three main enzymatic and medically important toxins from the venom was evaluated using synthetic substrates and quantified by chromogenic activity assays. Additionally, the neutralization of lethality, hemorrhage and edema were investigated by in vivo assays. The possible interactions between venom proteins and plant molecules were visualized by polyacrylamide gel electrophoresis. Finally, the phytochemical constituents present in the ethanolic extract were determined by qualitative and quantitative analyses. The ethanolic extract reduced the activity of the three main enzymes of venom target, achieving ranges from 19% to 81% of inhibition. Our in vivo venom neuralizations assays showed a significant inhibition of edema (38.72%) and hemorrhage (42.90%). Additionally, lethality was remarkably counteracted. The highest extract ratio evaluated had a 75% survival rate. Our data support the biomedical value of U. sagittifolia as a source of natural enzyme inhibitors able to neutralize catalytically active B. atrox venom toxins and their toxic effects.
Asunto(s)
Araceae , Bothrops , Venenos de Crotálidos , Mordeduras de Serpientes , Animales , Antivenenos/química , Antivenenos/farmacología , Venenos de Crotálidos/toxicidad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Etanol/química , Hemorragia/inducido químicamente , Hemorragia/tratamiento farmacológico , Extractos Vegetales/química , Extractos Vegetales/farmacología , Mordeduras de Serpientes/tratamiento farmacológicoRESUMEN
Silver nanoparticles (AgNPs) are one of the most produced nanoproducts due to their unique biocide properties. The natural organic matter has an important impact on nanoparticle's dispersion as it may alter their fate and transport, as well as their bioavailability and toxicity. Therefore, this study aimed to evaluate the mitigatory effect of humic acids (HAs) on AgNP toxicity. For this purpose, we carried out an ex vivo exposure of gill of Piaractus mesopotamicus fish to 100 µg L-1 of AgNPs or AgNO3, alone and in combination with 10 mg L-1 of HAs. In parallel, a complete AgNP characterization in the media, including the presence of HAs, was provided, and the Ag+ release was measured. We analyzed Ag bioaccumulation, antioxidant enzymes activities, lipid peroxidation, antioxidant capacity against peroxyl radicals, and reduced glutathione levels in fish tissue. Our results indicated the Ag+ release from AgNPs decreased 28% when the HAs were present in the media. The Ag accumulation in gill tissue exposed to AgNPs alone was higher than the AgNO3 exposure, and sixfold higher than the treatment with the HA addition. Moreover, after both Ag forms, the catalase enzyme augmented its activity. However, those responses were mitigated when the HAs were present in the media. Then, our results suggested the mitigation by HAs under the exposure to both Ag forms, providing valuable information about the fate and behavior of this emergent pollutant.
Asunto(s)
Nanopartículas del Metal , Contaminantes Químicos del Agua , Animales , Branquias/química , Sustancias Húmicas , Nanopartículas del Metal/toxicidad , Plata/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
BACKGROUND: To date, there is no specific literature available on the determinants for therapeutic failure (TF) with meglumine antimoniate (MA) in Northwestern-Argentina. This study aimed to identify epidemiological, clinical, and treatment-related factors that could be involved in TF. METHODOLOGY/PRINCIPAL FINDINGS: We performed a case-control study. Cases were represented by patients who showed TF after administration of the first course of MA treatment, whereas, controls were determined as patients who evolved towards healing after the first MA cycle received. Crude Odds Ratios and their corresponding 90% confidence intervals (CI) were calculated, and risk factors were then tested by multivariate analysis using logistic binary regression. Three hundred and eighty-four patients with a presumptive diagnosis of ACL were recruited, and 153 with a positive diagnosis were selected. We included in the study 71 patients, who underwent specific treatment with MA, presented complete data on response to treatment, and had a minimum post-treatment follow-up of 6 months in cutaneous leishmaniasis, and 12 months in mucosal leishmaniasis. Of these, 34 (47.9%) presented TF. In the initial analysis, TF was significantly associated with the geographical area of disease acquisition (p = 0.036), the presence of mucosal lesions (p = 0.042), the presence of concomitant skin and mucosal lesions (p = 0.002), and lesion age ≥ 6 months (p = 0.018). Risk factors influencing TF in the final multivariate model included the geographical area where the disease was acquired (adjusted Odd Ratio 8.062; 95% CI 1.914-33.959; p = 0.004), and lesion age ≥ 6 months (adjusted Odd Ratio 10.037; 95% CI 1.383-72.843; p = 0.023). CONCLUSIONS/SIGNIFICANCE: The results of the present study suggest the existence of some risk factors linked to TF in Northwestern-Argentina, which deserve further investigation. Herein we recorded a high percentage of TF and we described clinical and epidemiological characteristics associated with TF that could be taken into account improving the clinical management of patients.
Asunto(s)
Antiprotozoarios/uso terapéutico , Leishmaniasis Cutánea/tratamiento farmacológico , Antimoniato de Meglumina/uso terapéutico , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Insuficiencia del TratamientoRESUMEN
We report the alterations of immunological parameters of a patient with visceral leishmaniasis caused by Leishmania (Leishmania) infantum from the Northwest of Argentina during active disease and after achieving clinical recovery. We first demonstrated elevated amounts of IFN-y, IL-10, B-cell activating factor (BAFF) and IgG in plasma during active disease, which returned to control values after recovery. In relation to T cell profile, we measured CD27, CD28, CD45RO, CD57 and perforin. We found a highly differentiated phenotype, preferentially in active disease and among CD8+ T cells, consisting in increased numbers of late differentiated and terminal effector cells. Although this highly differentiated CD8+ T cell phenotype persisted after recovery, a clear increase of central memory cells was recorded for both T subsets at that point, suggesting signs of reversion toward a less differentiated profile. The composition of the B cell compartment was slightly modified during active disease. Herein we document the global impact of severe visceral leishmaniasis on immunological parameters, which tend to revert upon clinical recovery, suggesting signs of immune restoration accompanying clinical improvement. The evaluated parameters could eventually be used as biomarkers of clinical evolution of visceral leishmaniasis.
En el presente trabajo informamos la afectación de parámetros inmunológicos durante la etapa grave de la infección y luego de alcanzar la recuperación clínica en un paciente autóctono del Noroeste argentino con leishmaniasis visceral causada por Leishmania (Leishmania) infantum. Detectamos concentraciones plasmáticas elevadas de interferón-y, interleuquina 10, IgG y BAFF (B-cell activating factor) durante la enfermedad activa, que se normalizaron luego de la recuperación clínica. En relación al perfil de diferenciación y memoria de las células T, clasificamos las células según la expresión de CD27, CD28, CD45RO, CD57 y perforina. Encontramos un fenotipo altamente diferenciado analizando la población de linfocitos T CD8+, con porcentajes aumentados de células T de diferenciación tardía y efectoras terminales. Si bien el fenotipo T CD8+ persistió luego de la recuperación clínica, pudimos observar un claro aumento de células T de memoria central en ese punto de estudio, sugiriendo signos de una posible reversión hacia un perfil T menos avanzado. El compartimiento de células B CD19+ mostró cambios más leves en la composición de las subpoblaciones de memoria. Documentamos el compromiso global de parámetros inmunológicos en la etapa grave de la leishmaniasis visceral que tienden a revertir luego de la recuperación, sugiriendo posibles signos de reconstitución inmune acompañando a la mejoría clínica. Los parámetros evaluados podrían ser útiles como biomarcadores de la evolución clínica de la enfermedad.
Asunto(s)
Leishmaniasis Visceral , Argentina , Linfocitos T CD8-positivos , HumanosRESUMEN
Resumen En el presente trabajo informamos la afectación de parámetros inmunológicos durante la etapa grave de la infección y luego de alcanzar la recuperación clínica en un paciente autóctono del Noroeste argentino con leishmaniasis visceral causada por Leishmania (Leishmania) infantum. Detectamos concentraciones plasmáticas elevadas de interferón-γ, interleuquina 10, IgG y BAFF (B-cell activating factor) durante la enfermedad activa, que se normalizaron luego de la recuperación clínica. En relación al perfil de diferenciación y memoria de las células T, clasificamos las células según la expresión de CD27, CD28, CD45RO, CD57 y perforina. Encontramos un fenotipo altamente diferenciado analizando la población de linfocitos T CD8+, con porcentajes aumentados de células T de diferenciación tardía y efectoras terminales. Si bien el fenotipo T CD8+ persistió luego de la recuperación clínica, pudimos observar un claro aumento de células T de memoria central en ese punto de estudio, sugiriendo signos de una posible reversión hacia un perfil T menos avanzado. El compartimiento de células B CD19+ mostró cambios más leves en la composición de las subpoblaciones de memoria. Documentamos el compromiso global de parámetros inmunológicos en la etapa grave de la leishmaniasis visceral que tienden a revertir luego de la recuperación, sugiriendo posibles signos de reconstitución inmune acompañando a la mejoría clínica. Los parámetros evaluados podrían ser útiles como biomarcadores de la evolución clínica de la enfermedad.
Abstract We report the alterations of immunological parameters of a patient with visceral leishmaniasis caused by Leishmania (Leishmania) infantum from the Northwest of Argentina during active disease and after achieving clinical recovery. We first demonstrated elevated amounts of IFN-γ, IL-10, B-cell activating factor (BAFF) and IgG in plasma during active disease, which returned to control values after recovery. In relation to T cell profile, we measured CD27, CD28, CD45RO, CD57 and perforin. We found a highly differentiated phenotype, preferentially in active disease and among CD8+ T cells, consisting in increased numbers of late differentiated and terminal effector cells. Although this highly differentiated CD8+ T cell phenotype persisted after recovery, a clear increase of central memory cells was recorded for both T subsets at that point, suggesting signs of reversion toward a less differentiated profile. The composition of the B cell compartment was slightly modified during active disease. Herein wedocument the global impact of severe visceral leishmaniasis on immunological parameters, which tend to revert upon clinical recovery, suggesting signs of immune restoration accompanying clinical improvement. The evaluated parameters could eventually be used as biomarkers of clinical evolution of visceral leishmaniasis.
Asunto(s)
Humanos , Leishmaniasis Visceral , Argentina , Linfocitos T CD8-positivosRESUMEN
BACKGROUND: In the present study, we evaluate the results of gamma knife surgery (GKS) for the treatment of trigeminal neuralgia (TN) using the trigeminal ganglion (TG') and the adjacent fibers of trigeminal nerve as a target. METHODS: From February 2013 to July 2017, we treated 30 cases of TN with GKS. In this group, all patients had an idiopathic typical TN. The radiosurgical target was conformed through two isocenters, 8 and 4 mm at the cavum de Meckel. The maximum dose was 86 Gy using the isodose line of 50%. The median age of the patients was 58.5 (range 28-94) years old, and the median time from diagnosis to GKS was 94 months (range 13-480 months). The median follow-up was 28.5 (range 12-49) months. Clinical outcomes were analyzed. Univariate and multivariate analyses were performed to evaluate factors that correlated with a favorable, pain-free outcome. RESULTS: The mean time to relief of pain was 7 (range 1-40) days. The percentage of patients with significant pain relief was 93.3%. Relapse in pain was noted in four patients at 3, 16, 19, and 36 months. Nine patients were treated in acute status. Fourteen patients had intense pain between 1 and 7 days before the procedure. Among those with the recurrence of their symptoms, one patient had a microvascular decompression. Multivariate regression adjusted for age and sex suggests that, by 40 months, 70% of the patients treated with radiosurgery will remain pain free. At the last follow-up, GKS resulted in pain relief in 86.6% of patients. Our analysis suggests that, using this technique, we can expect that approximately 70% of patients with TN will have some degree of pain improvement at 3 years' post radiosurgery. CONCLUSIONS: GKS on TG appears to be a reasonable treatment option with short latency period, minor collateral effects, and high percentage of pain control. The mechanism of action of radiosurgery could be related to the inactivation of the satellite glial cells in the TG.
RESUMEN
The application of pectinases in industrial olive-oil processes is restricted by its production cost. Consequently, new fungal strains able to produce higher pectinase titers are required. The aim of this work was to study the capability of Aspergillus giganteus NRRL10 to produce pectinolytic enzymes by SSF and evaluate the application of these in olive-oil extraction. A. giganteus was selected among 12 strains on the basis of high pectinolytic activity and stability. A mixture composed by wheat bran, orange, and lemon peels was selected as the best substrate for enzyme production. Statistical analyses of the experimental design indicated that pH, temperature, and CaCl2 are the main factors that affect the production. Subsequently, different aeration flows were tested in a tray reactor; the highest activity was achieved at 20 L min-1 per kilogram of dry substrate (kgds). Finally, the pectinolytic enzymes from A. giganteus improved the oil yield and rheological characteristics without affecting oil chemical properties.
Asunto(s)
Aspergillus/enzimología , Fermentación , Manipulación de Alimentos , Aceite de Oliva , Poligalacturonasa/biosíntesis , Aspergillus/clasificación , Reactores Biológicos , Fenómenos Químicos , Medios de Cultivo/química , Concentración de Iones de Hidrógeno , Microbiología Industrial , TemperaturaRESUMEN
American tegumentary leishmaniasis displays two main clinical forms: cutaneous (CL) and mucosal (ML). ML is more resistant to treatment and displays a more severe and longer evolution. Since both forms are caused by the same Leishmania species, the immunological response of the host may be an important factor determining the evolution of the disease. Herein, we analyzed the differentiation and memory profile of peripheral CD4(+) and CD8(+) T lymphocytes of patients with CL and ML and their Leishmania-T. cruzi co-infected counterparts. We measured the expression of CD27, CD28, CD45RO, CD127, PD-1 and CD57, together with interferon-γ and perforin. A highly differentiated phenotype was reflected on both T subsets in ML and preferentially on CD8(+) T cells in CL. A positive trend toward a higher T differentiation profile was found in T. cruzi-infected CL and ML patients as compared with Leishmania single infections. Association between CD8(+) T-cell differentiation and illness duration was found within the first year of infection, with progressive increase of highly differentiated markers over time. Follow-up of patients with good response to therapy showed predominance of early differentiated CD8(+) T cells and decrease of highly differentiated cells, while patients with frequent relapses presented the opposite pattern. CD8(+) T cells showed the most striking changes in their phenotype during leishmaniasis. Patients with long-term infections showed the highest differentiated degree implying a relation between T differentiation and parasite persistence. Distinct patterns of CD8(+) T differentiation during follow-up of different clinical outcomes suggest the usefulness of this analysis in the characterization of Leishmania-infected patients.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Enfermedad de Chagas/patología , Coinfección/patología , Leishmaniasis Mucocutánea/patología , Subgrupos de Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/análisis , Diferenciación Celular , Niño , Femenino , Estudios de Seguimiento , Humanos , Inmunofenotipificación , Interferón gamma/análisis , Masculino , Persona de Mediana Edad , Perforina/análisis , Adulto JovenRESUMEN
Leishmaniasis is a parasitic disease caused by hemoflagellates of the genus Leishmania and is transmitted to humans by the bite of infected phlebotomine sandflies. Depending on the Leishmania species, the disease has different clinical forms including cutaneous, mucocutaneous, and visceral manifestations. Previous studies performed in endemic zones of northwestern-Argentina, during epidemic outbreaks, have been important for detecting patients suffering from the acute phase of the disease, but have not given a complete representation of the clinical and epidemiological features in the region. Furthermore, due to the resurgence of leishmaniasis worldwide and in particular the large increase of international tourism to the region, it seems pertinent to update the current epidemiological and clinical profile of leishmaniasis in northwestern-Argentina. Here we present a retrospective analysis of 95 Leishmania positive cases, presenting between 2000 and 2014. Patients were derived from hospitals and diagnosed in our lab at the University of Salta, located in a non-endemic area in Salta, Argentina. We detected numerous extensive mucocutaneous cases (34/95, 35.8%) distinct from mucosal affected patients, some instances originating in locations with no previously reported human cases. Additionally patients suffering from concomitant diseases, besides leishmaniasis, were assessed. These included Chagas disease, syphilis, deep mycoses, tuberculosis, toxoplasmosis and intestinal parasitosis. This study updates the clinical and epidemiological features of leishmaniasis in northwestern-Argentina, and discusses the implications and management strategy for patients who acquire the disease in this region.
Asunto(s)
Leishmaniasis Mucocutánea/epidemiología , Leishmaniasis Visceral/epidemiología , Adolescente , Adulto , Animales , Anticuerpos Antiprotozoarios/inmunología , Argentina/epidemiología , Enfermedad de Chagas/epidemiología , Niño , Preescolar , Comorbilidad , Brotes de Enfermedades , Femenino , Humanos , Lactante , Leishmania , Leishmania braziliensis , Leishmania infantum , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/parasitología , Leishmaniasis Mucocutánea/inmunología , Leishmaniasis Mucocutánea/parasitología , Leishmaniasis Visceral/inmunología , Leishmaniasis Visceral/parasitología , Masculino , Persona de Mediana Edad , Micosis/epidemiología , Psychodidae/parasitología , Estudios Retrospectivos , Sífilis/epidemiología , Toxoplasmosis/epidemiología , Tuberculosis/epidemiología , Adulto JovenRESUMEN
Leishmaniases comprise zoonotic diseases caused by protozoan flagellates of the Leishmania genus. They are endemic to South America, and the visceral form has been recently reported in Argentina. Dogs can play different roles in the Leishmania transmission cycles, depending mainly on the species of parasite involved. Here we focused on the clinical characterization of canine leishmaniasis (CanL) in Northeast Argentina and on the molecular typing of its etiological agent. The nested polymerase chain reaction and sequence analysis of the Leishmania cytochrome b (cyt b) gene was performed on DNA templates purified from lymph nodes, bone marrow or spleen aspirates obtained from 48 dogs previously diagnosed by the observation of Leishmania amastigotes on smears from these aspirates. Their clinical and epidemiological data were also recorded. Systemic abnormalities were observed in 46 subjects (95.8%), most frequently lymphadenopathy, and emaciation (89.6 and 75%). Furthermore, 87% also presented tegumentary abnormalities, such as alopecia (54.2%) or secondary skin lesions (47.9%), among others. Twenty three dogs were positive for cyt b amplification. The sequence analysis showed the presence of two genotypes, LiA1 and LiA2, assigned to Leishmania (Leishmania) infantum, with 99.9 and 100% homology with the reference strain MHOM/TN/80/IPT1 respectively. LiA1 was identified in 18 cases (78.3%) and LiA2 in five (21.7%). Two cyt b variants of L. (L.) infantum were incriminated as the causative agents of CanL cases from three cities: Posadas, Garupá, and Ituzaingó. All three cities are located in the northeastern area of the country, where these parasites seem to be spreading in urban areas.
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Enfermedades de los Perros/epidemiología , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/veterinaria , Animales , Argentina/epidemiología , Reservorios de Enfermedades , Perros , Femenino , Leishmania infantum/genética , Leishmaniasis Visceral/epidemiología , Masculino , Reacción en Cadena de la Polimerasa , ZoonosisRESUMEN
Cases of human visceral leishmaniasis (HVL) were not recorded until recently in the Chaco region of northwestern Argentina. Dogs were surveyed at the sites of infection of two HVL index cases in the Chaco region of Salta province. Canine cases (CanL) were diagnosed by two parasitological methods, two molecular methods targeting mini- and maxicircle DNA, and immunochromatographic dipstick. Among 77 dogs studied, 10 (13%) were found infected with Leishmania spp. In seven dogs and two humans, the infecting species was typed as Leishmania (Leishmania) infantum. The same genotype was detected in the human and two of the CanL. Although several diagnostic methods displayed weak or moderate agreement, the concordance values for serology versus maxicircle PCR were very good (Kappa index = 0.84). Sandflies captured in the area were identified as Lutzomyia migonei and Lu. cortelezzii/Lu. sallesi (cortelezzii complex). The focal appearance of leishmaniasis in dogs and humans in a sylvatic region and its relatively low prevalence of infection suggests that L. (L.) infantum transmission to dogs and humans may, in this region, stem from sylvatic reservoirs.
Asunto(s)
Enfermedades de los Perros/epidemiología , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/veterinaria , Adulto , Animales , Argentina/epidemiología , Citocromos b/genética , ADN Protozoario/aislamiento & purificación , Enfermedades de los Perros/parasitología , Perros , Femenino , Genotipo , Humanos , Lactante , Insectos Vectores/parasitología , Leishmania infantum/genética , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Psychodidae/parasitologíaRESUMEN
American tegumentary leishmaniasis (ATL) is a group of zoonotic diseases caused by kinetoplastid flagellates of the genus Leishmania. A total of 66 patients diagnosed as positive ATL cases from northwest Argentina were included in this study. Leishmania stocks were isolated in vitro and analyzed over promastigote cultures sown on FTA through nested PCR and sequence of cytochrome b (cyt b). The molecular analysis resulted in the incrimination of L. (Viannia) braziliensis as the predominant species in the studied area, identifying two genotypes of L. (V.) braziliensis, 24 cases of Ab-1 cyt b and 41 cases of Ab-2 cyt b. One L. (V.) guyanensis strain was obtained from a traveler from the Brazilian Amazon. The prevalence of different genotypes was in agreement with previous studies, suggesting the necessity for new systems to study the genetic diversity in more detail. Most of the cases typified in this study were registered in the area of Zenta Valley (Orán, Hipólito Yrigoyen, and Pichanal cities), pointing a link between genotype and geographical origin of the sample. Sex and age distribution of the patients indicate that the transmission was predominantly associated with rural areas or rural activities, although the results might not exclude the possibility of peri-urban transmission. This work represents, so far, the largest isolation and molecular characterization of ATL cases in Argentina.
Asunto(s)
Citocromos b/clasificación , Leishmania braziliensis/aislamiento & purificación , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/epidemiología , Filogenia , Proteínas Protozoarias/clasificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Argentina/epidemiología , Niño , Preescolar , Citocromos b/genética , Femenino , Genotipo , Humanos , Lactante , Recién Nacido , Leishmania/clasificación , Leishmania/genética , Leishmania braziliensis/clasificación , Leishmania braziliensis/genética , Leishmaniasis Cutánea/parasitología , Masculino , Persona de Mediana Edad , Prevalencia , Proteínas Protozoarias/genéticaRESUMEN
The detection of specific nucleic acid (NA) sequences by PCR has revolutionized the biological and medical sciences. Real-time PCR (qPCR) opened up the possibility of obtaining quantitative results. NA extraction is a decisive step prior to qPCR since it may produce either the removal or co-extraction of inhibitory substances of the enzymatic reaction, which in turn affects the amplification efficiency. In the present work we compared the commercial NA extraction kits from Qiagen, Invitrogen and Macherey-Nagel, which were used to extract DNA from mice blood artificially infected with Trypanosoma cruzi and PP7 RNA, Pseudomonas aeruginosa bacteriophage, in spiked aqueous matrices. NA recovery efficiency in samples without inhibitors was similar for the three extraction kits. However, the Invitrogen kit was the only one that remained unaffected in the presence of inhibitors in the samples.
Asunto(s)
Sangre/microbiología , ADN Protozoario/aislamiento & purificación , Fagos Pseudomonas/genética , Pseudomonas aeruginosa/virología , Fagos ARN/genética , ARN Viral/aislamiento & purificación , Juego de Reactivos para Diagnóstico , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Inhibidores de la Transcriptasa Inversa/farmacología , Taninos/farmacología , Trypanosoma cruzi/genética , Animales , ADN Protozoario/genética , Guanidinas/farmacología , Masculino , Ratones , Concentración Osmolar , ARN Viral/genética , Tiocianatos/farmacología , AguaRESUMEN
BACKGROUND: The diagnosis of the leishmaniases poses enormous challenges in Argentina. The Polymorphism-Specific PCR (PS-PCR) designed and validated in our laboratories has been proven effective for typifying the Leishmania genus from cultured material. Here we evaluated the performance of this method in the diagnosis of American tegumentary leishmaniasis (ATL) and the rapid identification of Leishmania spp. directly from clinical specimens. METHODS: A total of 63 patients from northwestern Argentina, with cutaneous or mucocutaneous lesions, underwent an ATL diagnosis protocol which included clinical examination, Leishmanin skin test, and microscopic examination of dermal smears. In addition, we performed PS-PCR on DNA directly extracted from the specimens scraped from the lesions. RESULTS: Out of the 63 patients, 44 were classified as ATL cases and 19 as non-ATL cases. The diagnostic sensitivity of the microscopic analysis of dermal smears and PS-PCR individually were 70.5% and 81%, respectively. When performing both tests in parallel, this parameter increased significantly to 97.6% (p = 0.0018). The specificities, on the other hand, were 100%, 84.2%, and 83.3% for the combination, respectively (p > 0.05). Using the PS-PCR analysis we successfully identified the Leishmania spp. in 31 out of the 44 ATL cases. Twenty-eight (90.3%) cases were caused by L. (V.) braziliensis, two (6.5%) by L. (V.) guyanensis, and one (3.2%) by L. (V.) panamensis. CONCLUSIONS: The efficacy of the ATL diagnosis was significantly improved by combining the dermal smear examination with a PS-PCR analysis. Our strategy allowed us to reach the diagnosis of ATL with high accuracy regarding the species of the etiological agent in 70.5% of the cases. Moreover, we diagnosed two cases of the disseminated cutaneous form caused by L. (V.) braziliensis and a cutaneous case due to L. (V.) panamensis infection, both findings reported for the first time in Argentina.
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Leishmania/clasificación , Leishmania/aislamiento & purificación , Leishmaniasis Cutánea/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Parasitología/métodos , Reacción en Cadena de la Polimerasa/métodos , Adulto , Argentina , Femenino , Humanos , Leishmania/genética , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadAsunto(s)
Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/diagnóstico , Adulto , Argentina , Médula Ósea/parasitología , Citocromos b/genética , Humanos , Leishmania infantum/genética , Leishmaniasis Visceral/sangre , Leishmaniasis Visceral/parasitología , Masculino , Tipificación Molecular , Parasitemia/sangre , Parasitemia/parasitología , Proteínas Protozoarias/genética , Análisis de Secuencia de ADNRESUMEN
It is important to know whether the variability of species of Leishmania parasites circulating in a region affects the performance of the ELISA test for the diagnosis of leishmaniasis. Therefore, the aim of this study was to analyze the reactivity of the ELISA using homogenates of promastigotes of Leishmania (V.) braziliensis (ELISAb), Leishmania (L) amazonensis (ELISAa) and Leishmania (V.) guyanensis (ELISAg) against different sera groups. Samples from individuals with cutaneous leishmaniasis (n = 37), mucocutaneous leishmaniasis (n = 8), healthy controls (n = 52), persons infected with Trypanosoma cruzi (n = 11) and mixed infections (n = 14) were included in the study. We calculated sensitivities, specificities, cut offs, and predictive values for the three tests and compared them using ANOVA, kappa index, ROC curves comparison, and confidence intervals calculated by the bootstrap method. Significant differences were found when comparing the OD levels of sera from patients with cutaneous leishmaniasis against healthy controls, but there were no differences when comparing the different ELISAs. The sensitivities calculated for ELISAb and ELISAa were 84.6 and of 88.5% for ELISAg, while the value of specificity for the three tests was 96.2. The kappa index (0.87) and comparison of ROC curves showed similar performance for the three ELISAs (p = 0.225). The high reactivity obtained for these ELISAs in sera of patients with mucocutaneous leishmaniasis indicates this test as an important complement in the diagnosis of the disease.
Asunto(s)
Antígenos de Protozoos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Leishmania/inmunología , Leishmaniasis Cutánea/diagnóstico , Proteínas Protozoarias/sangre , Análisis de Varianza , Enfermedad de Chagas/inmunología , Intervalos de Confianza , Humanos , Leishmania braziliensis/inmunología , Leishmania guyanensis/inmunología , Leishmania mexicana/inmunología , Leishmaniasis Cutánea/inmunología , Leishmaniasis Mucocutánea/diagnóstico , Leishmaniasis Mucocutánea/inmunología , Sensibilidad y Especificidad , Trypanosoma cruzi/químicaRESUMEN
Es importante conocer si la variabilidad de especies de Leishmania circulantes en una región afecta la performance de las pruebas de ELISA estandarizadas para el diagnostico de la leishmaniasis. El objetivo de este trabajo fue analizar la reactividad de la prueba de ELISA utilizando homogenados de promastigotes de Leishmania (V.) braziliensis (ELISAb), L (L) amazonensis (ELISAa) y L (V.) guyanensis (ELISAg) frente a distintos grupos de sueros. Se estudiaron muestras de personas con leishmaniasis cutánea (n = 37), leishmaniasis mucocutánea (n = 8), no infectados (n = 52), infectadas por Trypanosoma cruzi (n = 11) e infecciones mixtas (n = 14). Se calcularon las sensibilidades, especificidades, cut off, valores predictivos, y se compararon las tres pruebas usando ANOVA, índice de concordancia kappa, comparación de curvas ROC e intervalos de confianza construidos por el método de bootstrap. Se encontraron diferencias significativas al comparar los niveles de DO de los sueros de pacientes con leishmaniasis cutánea respecto a los controles negativos, pero no se encontraron diferencias entre pruebas. Las sensibilidades calculadas fueron de 84.6% para ELISAb y ELISAa y de 88.5 para ELISAg, mientras que el valor de especificidad para las tres pruebas fue de 96.2. El índice de concordancia kappa y la comparación de curvas ROC mostraron performances similares para las tres pruebas (p = 0.225). La elevada reactividad obtenida para estas ELISAs frente a sueros de pacientes con leishmaniasis mucocutánea indica un importante potencial de esta técnica como complemento en el diagnóstico de la enfermedad.
It is important to know whether the variability of species of Leishmania parasites circulating in a region affects the performance of the ELISA test for the diagnosis of leishmaniasis. Therefore, the aim of this study was to analyze the reactivity of the ELISA using homogenates of promastigotes of Leishmania (V.) braziliensis (ELISAb), Leishmania (L) amazonensis (ELISAa) and Leishmania (V.) guyanensis (ELISAg) against different sera groups. Samples from individuals with cutaneous leishmaniasis (n = 37), mucocutaneous leishmaniasis (n = 8), healthy controls (n = 52), persons infected with Trypanosoma cruzi (n = 11) and mixed infections (n = 14) were included in the study. We calculated sensitivities, specificities, cut offs, and predictive values for the three tests and compared them using ANOVA, kappa index, ROC curves comparison, and confidence intervals calculated by the bootstrap method. Significant differences were found when comparing the OD levels of sera from patients with cutaneous leishmaniasis against healthy controls, but there were no differences when comparing the different ELISAs. The sensitivities calculated for ELISAb and ELISAa were 84.6 and of 88.5% for ELISAg, while the value of specificity for the three tests was 96.2. The kappa index (0.87) and comparison of ROC curves showed similar performance for the three ELISAs (p = 0.225). The high reactivity obtained for these ELISAs in sera of patients with mucocutaneous leishmaniasis indicates this test as an important complement in the diagnosis of the disease.
Asunto(s)
Humanos , Antígenos de Protozoos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Leishmania/inmunología , Leishmaniasis Cutánea/diagnóstico , Proteínas Protozoarias/sangre , Análisis de Varianza , Intervalos de Confianza , Enfermedad de Chagas/inmunología , Leishmania braziliensis/inmunología , Leishmania guyanensis/inmunología , Leishmania mexicana/inmunología , Leishmaniasis Cutánea/inmunología , Leishmaniasis Mucocutánea/diagnóstico , Leishmaniasis Mucocutánea/inmunología , Sensibilidad y Especificidad , Trypanosoma cruzi/químicaRESUMEN
La Leishmaniasis es una enfermedad endémica en la provincia de Salta, Argentina, con cientos de casos anuales. La identificación de la especie de Leishmania es necesaria debido a diferencias de presentación clínica y de respuesta al tratamiento entre especies. La técnica PS-PCR ha sido validada con el método de isoenzimas para la identificación de especies de Leishmania en Argentina. OBJETIVOS: optimizar la técnica PS-PCR para identificar la especie de parásitos aislados por cultivo y en muestras clínicas de pacientes de Salta y correlacionarla con sus características clínicas y su respuesta al tratamiento. RESULTADOS: La PS-PCR permitió identificar la especie de Leishmania en las 24 muestras analizadas: 9 aislados de cultivo y 15 muestras clínicas de raspado de lesiones (100% de especificidad). Las especies halladas fueron:L(V) braziliensis (19/24; p< 0,0001), L(L) amazonensis (4/24) yL(V) guyanensis (1/24). La primera estuvo relacionada con todos los casos severos (8 con lesiones mucocutáneas y 1 con enfermedad diseminada), y con todas las fallas al tratamiento con Glucantime(4) observadas. En los casos de L(L) amazonensis, no se observó enfermedad grave ni resistencia al tratamiento. El caso deL(V) guyanensis no era autóctono de la zona. CONCLUSIONES: Este estudio demuestra que la técnica PS-PCR es apropiada para el diagnóstico específico de la leishmaniasis. El diagnóstico deL(V) braziliensis obliga a considerar tratamientos alternativos para los casos severos de la enfermedad
Leishmaniasis is endemic in the province of Salta, Argentina, with hundreds of cases annually. Identifying the species of Leishmania is necessary due to differences in clinical presentation and treatment response between species. PS-PCR technique has been validated by the method of isozymesto identify Leishmania species in Argentina. OBJECTIVES:To optimize the PS-PCR technique to identify the species of parasites isolated by culture and in clinical specimens from patients of Salta and its correlation with clinical characteristics and response to treatment. RESULTS: The PS-PCR allowed us to identify the species of Leishmania in 24 samples analyzed: 9 isolated from clinical specimens and 15 culture swabs taken from lesions (100% specificity). The species found were: L(V)braziliensis (19/24, P <0.0001), L(L) amazonensis (4/24) andL(V) guyanensis (1/24). The first one was related to all severe cases (8 with mucocutaneous lesions and 1 with disseminated disease), and to all failures to treatment with Glucantime (4)observed. In the cases of L(L) amazonensis, there were noserious disease or resistance to treatment. The case of L(V)guyanensis was not indigenous to the area. CONCLUTIONS:This study demonstrates that PS-PCR technique is suitable for specific diagnosis of leishmaniasis. The diagnosis of L(V)braziliensis under takes to consider alternative treatments for severe cases of the disease
Asunto(s)
Humanos , Citocromos b , Isoenzimas/clasificación , Leishmania/parasitología , Reacción en Cadena de la Polimerasa/métodosRESUMEN
Trypanosoma cruzi is genetically classified into six discrete phylogenetic lineages on the basis of different genetic markers. Identifying lineages circulating among humans in different areas is essential to understand the molecular epidemiology of Chagas disease. In the present study, 18 T. cruzi isolates from congenitally infected newborns in the northwestern province of Salta-Argentina were studied by multilocus enzyme electrophoresis (MLEE) and random amplified polymorphic DNA (RAPD). All isolates were typed by MLEE and RAPD as belonging to T. cruzi IId. Analysis of minor variants of TcIId using probes hybridizing with hypervariable domains of kDNA minicircles, detected three variants with a similar distribution among the isolates. Our findings confirm the presence of T. cruzi IId among congenitally infected newborns in northwestern Argentina and support the assumption that human infection by T. cruzi in the Southern Cone countries of Latin America is due principally to T. cruzi II.