RESUMEN
Orthohantaviruses are zoonotic pathogens that cause acute and severe syndromes in humans. This review was performed to estimate the occurrence of human orthohantaviruses in South America between 2010 and 2022. A careful evaluation of the eligibility and quality of the articles was carried out after a systematic bibliographic search of four databases. The pooled frequency of human orthohantaviruses was calculated using a random effects model meta-analysis. The heterogeneity of estimates (resulting from the chi2 test and I2 statistics) was investigated by subgroup analysis and meta-regression. 1,962 confirmed cases of orthohantavirus infections were diagnosed among 35,548 individuals from seven South American countries. The general occurrence of orthohantaviruses was estimated to be 4.4% (95% confidence interval: 2.9-6.2%) based on general pooling of human cases from 32 studies. In a subgroup analysis considering the study design and method of diagnosis, the percentages of diagnosed orthohantavirus infections differed substantially (I2 = 97.8%, p = 0.00) among South American countries. Four genetic variants of orthohantavirus have been identified circulating in Argentina, Brazil, Bolivia, Chile, Colombia, and Peru. Although laboratory diagnosis of orthohantaviruses is not performed in many countries in South America, there is evidence that four different orthohantaviruses are circulating in the region. The pooled occurrence of viral infection was approximately 4.0% in more than half of the South American countries. Updated information on the occurrence of human infections is essential for monitoring the territorial spread and determining the frequency of this zoonosis.
Asunto(s)
Infecciones por Hantavirus , Orthohantavirus , Animales , Humanos , Infecciones por Hantavirus/epidemiología , Infecciones por Hantavirus/virología , Orthohantavirus/genética , Orthohantavirus/clasificación , Orthohantavirus/aislamiento & purificación , América del Sur/epidemiologíaRESUMEN
Connexin (Cx) expression is reportedly altered in neoplasms. This study aimed to investigate the expression of Cx43, 26 and 32 in normal and pathological canine perianal glands. Thirty perianal glands bearing pathological processes and ten normal canine perianal glands were submitted to immunohistochemistry to search for presence of Cx43, Cx26 and Cx32. Both Cx43 and Cx26 expressions were observed in normal, hyperplastic glands, and in well and moderately differentiated adenomas. However, in poorly differentiated adenomas, expressions were reduced, and they were absent in carcinomas. Cx26 was located in the cytoplasm of normal, hyperplastic perianal gland cells, and in well and moderately differentiated adenomas. Cx32 was not observed in any neoplasm neither in normal or hyperplastic glands. Our results show that Cx43 and Cx26 expressions are altered in more aggressive canine perianal gland neoplasms, and we conclude that they may be related to the perianal gland carcinogenesis process
Asunto(s)
Animales , /análisis , Conexinas/análisis , Conexinas/inmunología , Neoplasias de las Glándulas Anales/diagnóstico , Neoplasias de las Glándulas Anales/microbiología , Sinapsis Eléctricas/patologíaRESUMEN
Angiogenesis is involved in several physiological and pathological processes, and the proliferation of endothelial cells is a central event in the generation of new blood vessels. Gap junctions (GJ) are membrane structures that communicate adjacent cells, contribute to tissue homeostasis, and are important to the control of cell proliferation. Connexins (Cxs) are the proteins that form gap junctions. Endothelial cells may express Cx43, Cx37 and Cx40. In this study, we analyzed the effect of the heterologous deletion of the Gja1 (Cx43 gene) on the development of newly formed blood vessels (NFBV) in the mouse cornea. Heterozygous (Cx43+/-) and wild-type (Cx43+/+) mice were submitted to the silver crystal corneal cauterization model. Two parameters were quantified by image analysis 2 or 6 days after cauterization: NFBV density and length. At days 2 and 6 after corneal cauterization, Cx43+/- mice showed smaller density of NFBV as compared to Cx43+/+ mice. Therefore, deletion of one Gja1 allele (connexin-43 gene) may lead to impaired cell-cell communication in endothelial cells, diminishing angiogenesis after cauterization of the mouse cornea
Asunto(s)
Animales , /farmacología , Células Endoteliales/patología , Neovascularización de la Córnea/cirugía , Neovascularización de la Córnea/veterinaria , Sinapsis Eléctricas/patología , Homeostasis , Tamización de Portadores GenéticosRESUMEN
Angiogenesis is involved in several physiological and pathological processes, and the proliferation of endothelial cells is a central event in the generation of new blood vessels. Gap junctions (GJ) are membrane structures that communicate adjacent cells, contribute to tissue homeostasis, and are important to the control of cell proliferation. Connexins (Cxs) are the proteins that form gap junctions. Endothelial cells may express Cx43, Cx37 and Cx40. In this study, we analyzed the effect of the heterologous deletion of the Gja1 (Cx43 gene) on the development of newly formed blood vessels (NFBV) in the mouse cornea. Heterozygous (Cx43+/-) and wild-type (Cx43+/+) mice were submitted to the silver crystal corneal cauterization model. Two parameters were quantified by image analysis 2 or 6 days after cauterization: NFBV density and length. At days 2 and 6 after corneal cauterization, Cx43+/- mice showed smaller density of NFBV as compared to Cx43+/+ mice. Therefore, deletion of one Gja1 allele (connexin-43 gene) may lead to impaired cell-cell communication in endothelial cells, diminishing angiogenesis after cauterization of the mouse cornea(AU)
Asunto(s)
Animales , Neovascularización de la Córnea/cirugía , Neovascularización de la Córnea/veterinaria , Células Endoteliales/patología , Conexina 43/farmacología , Sinapsis Eléctricas/patología , Homeostasis , Tamización de Portadores GenéticosRESUMEN
Connexin (Cx) expression is reportedly altered in neoplasms. This study aimed to investigate the expression of Cx43, 26 and 32 in normal and pathological canine perianal glands. Thirty perianal glands bearing pathological processes and ten normal canine perianal glands were submitted to immunohistochemistry to search for presence of Cx43, Cx26 and Cx32. Both Cx43 and Cx26 expressions were observed in normal, hyperplastic glands, and in well and moderately differentiated adenomas. However, in poorly differentiated adenomas, expressions were reduced, and they were absent in carcinomas. Cx26 was located in the cytoplasm of normal, hyperplastic perianal gland cells, and in well and moderately differentiated adenomas. Cx32 was not observed in any neoplasm neither in normal or hyperplastic glands. Our results show that Cx43 and Cx26 expressions are altered in more aggressive canine perianal gland neoplasms, and we conclude that they may be related to the perianal gland carcinogenesis process (AU)
Asunto(s)
Animales , Neoplasias de las Glándulas Anales/diagnóstico , Neoplasias de las Glándulas Anales/microbiología , Conexina 43/análisis , Conexinas/análisis , Conexinas/inmunología , Sinapsis Eléctricas/patologíaRESUMEN
Compensatory kidney hypertrophy/hyperplasia leads to several changes in kidney structure and function, as increased glomeruli filtration. The aim of this study was to evaluate connexin 43 in remnant mouse kidneys after unilateral nephrectomy. The right kidney was surgically removed from BALB/c mice. Groups were euthanized at 24, 48 and 72 hours, and at 7 and 30 days. Kidney sections of the reminiscent kidneys were stained with Periodic Acid/Schiff and additional slides were submitted to BrdU and Cx43 immunohistochemistry. The results demonstrated an increase in kidney weight as early as 24 hours through 30 post-nephrectomy. In addition, BrdU positive epithelial cells increased at 24 and 48 hours post-nephrectomy. Cx43 was detected in the cytoplasm and membrane of epithelial cells and vasculature. Taking into consideration the quantity, intensity and localization of Cx43 immunostaining pattern, we observed that nephrectomized mice presented lower Cx43 expression and a cytoplasmic localization after 24 hours, peaking in 48 hours. Furthermore, western blot revealed that during the first 24 and 48 hours after nephrectomy, PO (unphosphorylated) and P1 (phosphorylated) Cx43 disappeared, and the products of Cx43 degradation were reduced. On the other hand, after 72 hours the PO and P1 state reappeared and the amount of degraded peptides also increased. Seven and thirty days after nephrectomy, a higher intensity of PO and P1 state and a lower P2 (hyperphosphorylated) band were observed. In conclusion, our results suggest that Cx43 phosphorylation results in the retention of Cx43 in cytoplasm and its increased degradation during compensatory renal hyperplasia/hypertrophy.
Asunto(s)
Animales , Ratones , Uniones Comunicantes , Conexina 43/análisis , Isoformas de Proteínas/análisis , Hiperplasia/veterinaria , Hipertrofia/veterinaria , Riñón/cirugía , Ratones Endogámicos BALB C/cirugía , Nefrectomía/veterinariaRESUMEN
Senna occidentalis (L) Link (formerly called Cassia occidentalis) is a toxic leguminous plant found ubiquitously as a contaminant of crops. All parts of the plant are toxic, but most of the S. occidentalis toxicity is found in the seeds. S. occidentalis has been shown to be toxic to several animal species, causing degenerative lesions mainly in muscles. This is the first report describing alterations in chick lymphoid organs caused by S. occidentalis seeds. The objectives of this study were to describe the effects of the treatment with seeds and its fraction external tegument (TE) on the development of chicks and their lymphoid organs bursa of Fabricius and spleen. Chicks that received a commercial ration with 1% TE had reduced body and lymphoid organ weights. The bursa of Fabricius presented reduction in the diameters of the follicles, and in the thickness of the cortical and medullary regions. The spleen presented depleted lymphoid tissue in the white pulp. These results indicate that the active principle of S. occidentalis is more concentrated on its TE fraction, and that it can cause weight loss as well as alterations in the lymphoid organs in chicks. The consequences of these alterations should be further investigated.