VEGF （Vascular endothelial growth factor） signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. H...VEGF （Vascular endothelial growth factor） signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. However, the ways in which infection with Paracoccidioides brasiliensis affects VEGF signaling and the influence of immunization with rPb27 （recombinant protein Pb27） on VEGF signaling have not yet been studied. Animals were immunized with rPb27 and subsequently infected with a virulent strain of P. brasiliensis. The fungal load was evaluated by measuring CFU （colony-forming unit） and histology was performed to evaluate the inflammatory reaction. At the two time points analyzed, the PC （positive control） and TREAT （treated） animals had decreased levels of pulmonary VEGF compared to basal levels. However, in the immunized （Pb27） and treated mice （Pb27 ＋ TREAT）, VEGF expression remained unchanged after infection. In the case of VEGFR-2, the Pb27 and Pb27 ＋ TREAT groups showed increased levels of expression. Regarding the levels of the eNOS enzyme, only the Pb27 group did not reduce the expression levels relative to baseline. The immunization with rPb27 kept VEGF signaling, NO production and increased VEGFR-2 expression, after infection with P. brasiliensis. Thus, the authors infer that immunization with rPb27 protects mice from the disruption of VEGF signaling in Paracoccidioides brasiliensis infection.展开更多
Efficient technologies for gene silencing would be important to carry out functional analysis with P. brasiliensis genes, as well as for a better understanding of the biology and pathogenesis of this pathogenic fungus...Efficient technologies for gene silencing would be important to carry out functional analysis with P. brasiliensis genes, as well as for a better understanding of the biology and pathogenesis of this pathogenic fungus. Due to the fact that homologous recombination is unusual in P. brasiliensis, the development of knockout isolates is currently non-feasible. The goal of this work was to assess RNA interference (RNAi) technology as an alternative tool for gene silencing previously employed successfully in H. capsulatum. For this purpose, we built different inverted repeat transgenic hairpin constructs to down-regulate the PbGP43 and PbP27 genes known to codify for two fungal immunogenic proteins that elicit a strong immune response during experimental paracoccidioidomycosis. Using the RNAi strategy, a reduction in the mRNA levels of the PbGP43 and PbP27 genes was observed during the first 20 days after selection;however, in the transformed yeast cells, the gene silencing status proved non-stable through the assay. We demonstrated that electrotransformation was suitable to transform P. brasiliensis yeast cells and integrate the hairpin constructions;nonetheless, gene silencing was not stable along the experimental time. A detailed analysis of the underlying molecular RNAi machinery may provide further insights into the intracellular mechanism that governs this reverse genetic tool.展开更多
BACKGROUND Paracoccidioidomycosis(PCM)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making i...BACKGROUND Paracoccidioidomycosis(PCM)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making investigation and treatment challenging.AIM To investigate the management of patients with visceral PCM admitted with EHC.METHODS All patients diagnosed with PCM treated in a public,tertiary teaching hospital between 1982 and 2020 were retrospectively evaluated.Those also identified with EHC were allocated to two groups according to the treatment approach for the purpose of comparing clinical,laboratory,and imaging findings,resources used for etiological diagnosis,treatment results,and prognosis.Statistical analyses were performed using the linear mixed-effects model(random and fixed effects),which was adjusted using the PROC MIXED procedure of the SAS®9.0 software,and Fisher’s exact test.RESULTS Of 1645 patients diagnosed with PCM,40(2.4%)had EHC.Of these,20(50.0%)lived in the rural area and 29(72.5%)were men,with a mean age of 27.1 years(3-65 years).Jaundice as first symptom and weight loss of at least 10 kg were observed in 16 patients(40.0%),and a mass in the head of the pancreas was observed in 8(20.0%).The etiological diagnosis was made by tissue collection during surgery in 4 cases(10.0%)and by endoscopic methods in 3 cases(7.5%).Twenty-seven patients(67.5%)received drug treatment alone(Group 1),whereas 13(32.5%)underwent endoscopic and/or surgical procedures in combination with drug treatment(Group 2).EHC was significantly reduced in both groups(40.7% in Group 1,with a mean time of 3 months;and 38.4% in Group 2,with a mean time of 7.5 months),with no statistically significant difference between them.EHC recurrence rates,associated mainly with treatment nonadherence,were similar in both groups:37% in Group 1 and 15.4% in Group 2.The mortality rate was 18.5% in Group 1 and 23% in Group 2,with survival estimates of 71.3% and 72.5%,respectively,with no statistically significant difference.CONCLUSION Although PCM-related EHC is rare,it needs to be included in the differential diagnosis of malignancies,as timely treatment can prevent hepatic and extrahepatic sequelae.展开更多
Paracoccidioidomycosis is the most prevalent systemic mycosis in Latin America. It is a fungal infection caused by the dimorphic fungus Paracoccidioides brasiliensis. This microorganism can penetrate the human body th...Paracoccidioidomycosis is the most prevalent systemic mycosis in Latin America. It is a fungal infection caused by the dimorphic fungus Paracoccidioides brasiliensis. This microorganism can penetrate the human body through direct contact and can cause intense lymphadenopathy, ulcerated lesions in the oral cavity and in the skin among other alterations. In this study, we report a case of paracoccidioidomycosis with unusual clinical presentation, as it manifested in the female sex and although it did not present any relevant complaints of respiratory focus, it presented a single ulcerated lesion in the buccal mucosa. A biopsy of the lesion and a mycological examination revealed Paracoccidioidesbrasiliensis infection.展开更多
文摘VEGF （Vascular endothelial growth factor） signaling is critical for endothelial cell survival and maintenance of the vasculature. Deregulation of VEGF signaling contributes to the physiopathology of many diseases. However, the ways in which infection with Paracoccidioides brasiliensis affects VEGF signaling and the influence of immunization with rPb27 （recombinant protein Pb27） on VEGF signaling have not yet been studied. Animals were immunized with rPb27 and subsequently infected with a virulent strain of P. brasiliensis. The fungal load was evaluated by measuring CFU （colony-forming unit） and histology was performed to evaluate the inflammatory reaction. At the two time points analyzed, the PC （positive control） and TREAT （treated） animals had decreased levels of pulmonary VEGF compared to basal levels. However, in the immunized （Pb27） and treated mice （Pb27 ＋ TREAT）, VEGF expression remained unchanged after infection. In the case of VEGFR-2, the Pb27 and Pb27 ＋ TREAT groups showed increased levels of expression. Regarding the levels of the eNOS enzyme, only the Pb27 group did not reduce the expression levels relative to baseline. The immunization with rPb27 kept VEGF signaling, NO production and increased VEGFR-2 expression, after infection with P. brasiliensis. Thus, the authors infer that immunization with rPb27 protects mice from the disruption of VEGF signaling in Paracoccidioides brasiliensis infection.
基金supported by Colciencias project No 221340820447the Corporacion para Investigaciones Biologicas(CIB)and the Universidad of Antioquia through the fund“Sostenibilidad 2010-2011”COLCIENCIAS National Doctoral Program supported Isaura Torres.
文摘Efficient technologies for gene silencing would be important to carry out functional analysis with P. brasiliensis genes, as well as for a better understanding of the biology and pathogenesis of this pathogenic fungus. Due to the fact that homologous recombination is unusual in P. brasiliensis, the development of knockout isolates is currently non-feasible. The goal of this work was to assess RNA interference (RNAi) technology as an alternative tool for gene silencing previously employed successfully in H. capsulatum. For this purpose, we built different inverted repeat transgenic hairpin constructs to down-regulate the PbGP43 and PbP27 genes known to codify for two fungal immunogenic proteins that elicit a strong immune response during experimental paracoccidioidomycosis. Using the RNAi strategy, a reduction in the mRNA levels of the PbGP43 and PbP27 genes was observed during the first 20 days after selection;however, in the transformed yeast cells, the gene silencing status proved non-stable through the assay. We demonstrated that electrotransformation was suitable to transform P. brasiliensis yeast cells and integrate the hairpin constructions;nonetheless, gene silencing was not stable along the experimental time. A detailed analysis of the underlying molecular RNAi machinery may provide further insights into the intracellular mechanism that governs this reverse genetic tool.
文摘BACKGROUND Paracoccidioidomycosis(PCM)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making investigation and treatment challenging.AIM To investigate the management of patients with visceral PCM admitted with EHC.METHODS All patients diagnosed with PCM treated in a public,tertiary teaching hospital between 1982 and 2020 were retrospectively evaluated.Those also identified with EHC were allocated to two groups according to the treatment approach for the purpose of comparing clinical,laboratory,and imaging findings,resources used for etiological diagnosis,treatment results,and prognosis.Statistical analyses were performed using the linear mixed-effects model(random and fixed effects),which was adjusted using the PROC MIXED procedure of the SAS®9.0 software,and Fisher’s exact test.RESULTS Of 1645 patients diagnosed with PCM,40(2.4%)had EHC.Of these,20(50.0%)lived in the rural area and 29(72.5%)were men,with a mean age of 27.1 years(3-65 years).Jaundice as first symptom and weight loss of at least 10 kg were observed in 16 patients(40.0%),and a mass in the head of the pancreas was observed in 8(20.0%).The etiological diagnosis was made by tissue collection during surgery in 4 cases(10.0%)and by endoscopic methods in 3 cases(7.5%).Twenty-seven patients(67.5%)received drug treatment alone(Group 1),whereas 13(32.5%)underwent endoscopic and/or surgical procedures in combination with drug treatment(Group 2).EHC was significantly reduced in both groups(40.7% in Group 1,with a mean time of 3 months;and 38.4% in Group 2,with a mean time of 7.5 months),with no statistically significant difference between them.EHC recurrence rates,associated mainly with treatment nonadherence,were similar in both groups:37% in Group 1 and 15.4% in Group 2.The mortality rate was 18.5% in Group 1 and 23% in Group 2,with survival estimates of 71.3% and 72.5%,respectively,with no statistically significant difference.CONCLUSION Although PCM-related EHC is rare,it needs to be included in the differential diagnosis of malignancies,as timely treatment can prevent hepatic and extrahepatic sequelae.
文摘Paracoccidioidomycosis is the most prevalent systemic mycosis in Latin America. It is a fungal infection caused by the dimorphic fungus Paracoccidioides brasiliensis. This microorganism can penetrate the human body through direct contact and can cause intense lymphadenopathy, ulcerated lesions in the oral cavity and in the skin among other alterations. In this study, we report a case of paracoccidioidomycosis with unusual clinical presentation, as it manifested in the female sex and although it did not present any relevant complaints of respiratory focus, it presented a single ulcerated lesion in the buccal mucosa. A biopsy of the lesion and a mycological examination revealed Paracoccidioidesbrasiliensis infection.
