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1.
Int J Mol Sci ; 25(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38892345

RESUMO

Overuse of antimicrobials has greatly contributed to the increase in the emergence of multidrug-resistant bacteria, a situation that hinders the control and treatment of infectious diseases. This is the case with urinary tract infections (UTIs), which represent a substantial percentage of worldwide public health problems, thus the need to look for alternatives for their control and treatment. Previous studies have shown the usefulness of autologous bacterial lysates as an alternative for the treatment and control of UTIs. However, a limitation is the high cost of producing individual immunogens. At the same time, an important aspect of vaccines is their immunogenic amplitude, which is the reason why they must be constituted of diverse antigenic components. In the case of UTIs, the etiology of the disease is associated with different bacteria, and even Escherichia coli, the main causal agent of the disease, is made up of several antigenic variants. In this work, we present results on the study of a bacterial lysate composed of 10 serotypes of Escherichia coli and by Klebsiella pneumoniae, Klebsiella aerogenes, Enterococcus faecalis, Proteus mirabilis, Citrobacter freundii, and Staphylococcus haemolyticus. The safety of the compound was tested on cells in culture and in an animal model, and its immunogenic capacity by analysing in vitro human and murine macrophages (cell line J774 A1). The results show that the polyvalent lysate did not cause damage to the cells in culture or alterations in the animal model used. The immunostimulatory activity assay showed that it activates the secretion of TNF-α and IL-6 in human macrophages and TNF-α in murine cells. The obtained results suggest that the polyvalent lysate evaluated can be an alternative for the treatment and control of chronic urinary tract infections, which will reduce the use of antimicrobials.


Assuntos
Infecções Urinárias , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia , Infecções Urinárias/imunologia , Infecções Urinárias/terapia , Animais , Humanos , Camundongos , Escherichia coli , Feminino , Extratos Celulares/farmacologia , Extratos Celulares/uso terapêutico , Lisados Bacterianos
2.
Pathogens ; 12(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38003825

RESUMO

Several questions regarding the evolution of SARS-CoV-2 remain poorly elucidated. One of these questions is the possible evolutionary impact of SARS-CoV-2 after the infection in domestic animals. In this study, we aimed to evaluate the potential role of cats as generators of relevant SARS-CoV-2 lineages during the pandemic. A total of 105 full-length genome viral sequences obtained from naturally infected cats during the pandemic were evaluated by distinct evolutionary algorithms. Analyses were enhanced, including a set of highly related SARS-CoV-2 sequences recovered from human populations. Our results showed the apparent high susceptibility of cats to the infection SARS-CoV-2 compared with other animal species. Evolutionary analyses indicated that the phylogenomic characteristics displayed by cat populations were influenced by the dominance of specific SARS-CoV-2 genetic groups affecting human populations. However, disparate dN/dS rates at some genes between populations recovered from cats and humans suggested that infection in these two species may suggest a different evolutionary constraint for SARS-CoV-2. Interestingly, the branch selection analysis showed evidence of the potential role of natural selection in the emergence of five distinct cat lineages during the pandemic. Although these lineages were apparently irrelevant to public health during the pandemic, our results suggested that additional studies are needed to understand the role of other animal species in the evolution of SARS-CoV-2 during the pandemic.

3.
Front Vet Sci ; 10: 1168846, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426077

RESUMO

Bovine viral diarrhea virus (BVDV) is considered the most important viral pathogen in ruminants worldwide due to the broad range of clinical manifestations displayed by infected animals. Therefore, infection with BVDV leads to severe economic losses in several countries' beef and dairy industries. Vaccination prevents reproductive failure and gastrointestinal and respiratory disorders caused by BVDV infection. However, considering their limitations, conventional vaccines such as live, attenuated, and killed viruses have been applied. Hence, different studies have described subunit vaccines as an effective and safe alternative for BVDV protection. Therefore, in this study, the ectodomain of E2 (E2e) glycoprotein from NADL BVDV strain was expressed in mammalian cells and used in two vaccine formulations to evaluate immunogenicity and protection against BVDV conferred in a murine model. Formulations consisted of solo E2e glycoprotein and E2e glycoprotein emulsified in adjuvant ISA 61 VG. Five groups of 6 mice of 6-to-8-week-old were immunized thrice on days 1, 15, and 30 by intraperitoneal injection with the mentioned formulations and controls. To evaluate the conferred protection against BVDV, mice were challenged six weeks after the third immunization. In addition, the humoral immune response was evaluated after vaccination and challenge. Mice groups inoculated with solo E2e and the E2e + ISA 61 VG displayed neutralizing titers; however, the E2 antibody titers in the E2e + ISA 61 VG group were significantly higher than the mice group immunized with the solo E2e glycoprotein. In addition, immunization using E2e + ISA 61 VG prevents animals from developing severe lesions in surveyed tissues. Moreover, this group acquired protection against the BVDV challenge, evidenced by a significant reduction of positive staining for BVDV antigen in the lungs, liver, and brain between the experimental groups. Our findings demonstrated that using E2e + ISA 61 VG induces greater BVDV protection by an early humoral response and reduced histopathological lesions and BVDV antigen detection in affected organs, indicating that E2e + ISA 61 VG subunit formulation can be considered as a putative vaccine candidate against BVDV. The efficacy and safety of this vaccine candidate in cattle requires further investigation.

4.
Front Vet Sci ; 8: 673577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34485426

RESUMO

Bovine viral diarrhea (BVD) is an infectious disease, globally-distributed, caused by bovine Pestiviruses, endemic of cattle and other ruminant populations. BVD leads to significant economic losses to the cattle industry due to the wide range of clinical manifestations, including respiratory and gastrointestinal diseases and reproductive disorders. Within the Pestivirus genus of the family Flaviviridae three viral species are associated with BVD; Pestivirus A (Bovine viral diarrhea virus 1, BVDV-1), Pestivirus B (Bovine viral diarrhea virus 2, BVDV-2), and Pestivirus H (HoBi-like pestivirus, atypical ruminant pestivirus). These species are subdivided into subgenotypes based on phylogenetic analysis. The extensive genetic diversity of BVDV has been reported for several countries, where the incidence and genetic variation are more developed in Europe than in the Americas. The first report of BVDV in Mexico was in 1975; this study revealed seropositivity of 75% in cows with a clinical history of infertility, abortions, and respiratory disease. Other studies have demonstrated the presence of antibodies against BVDV with a seroprevalence ranging from 7.4 to 100%. Recently, endemic BVDV strains affecting cattle populations started to be analyzed, providing evidence of the BVDV diversity in several states of the country, revealing that at least four subgenotypes (BVDV-1a, 1b, 1c, and 2a) are circulating in animal populations in Mexico. Little information regarding BVD epidemiological current status in Mexico is available. This review summarizes available information regarding the prevalence and genetic diversity viruses associated with BVD in cattle from Mexico.

5.
Arch Virol ; 166(7): 1999-2003, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33970345

RESUMO

In this communication, we report the presence of RNA of bovine viral diarrhea virus (BVDV) as a contaminant of different biological products used in Mexico for veterinary vaccine production. For this purpose, six batches of monovalent vaccines, eight cell line batches used for vaccine production, and 10 fetal bovine serum lots (FBS) commercially available in Mexico from different suppliers were tested by reverse transcription polymerase chain reaction (RT-PCR). Viral RNA was detected in 62.5% of the samples analyzed. Phylogenetic analysis revealed the presence of the subgenotypes BVDV-1a, 1b, and BVDV-2a in the tested samples. Collectively, these findings indicate that contamination by BVDV RNA occurs in commercial vaccines and reagents used in research and production of biological products. The ramifications of this contamination are discussed.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 2/genética , Vacinas Virais/genética , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/imunologia , Bovinos , Linhagem Celular , Vírus da Diarreia Viral Bovina Tipo 1/imunologia , Vírus da Diarreia Viral Bovina Tipo 2/imunologia , Genótipo , Síndrome Hemorrágica Bovina/microbiologia , México , Filogenia , RNA Viral/genética , Vacinas Virais/imunologia
6.
Vet. Méx ; 31(3): 209-216, jul.-sept. 2000. tab
Artigo em Espanhol | LILACS | ID: lil-304572

RESUMO

En este estudio se analizaron los valores sanguíneos normales de una mutante de ratones desnudos conocidos como et/et, se compararon con ratones CD 1, cepa de la cual surgió y con los heterocigóticos et/+. Los conteos leucocitarios y diferenciales mostraron que las poblaciones de leucocitos totales, linfocitos, monocitos y eosinófilos fueron significativamente mayores en los ratones et/et que en los CD 1 (P < 0.05); en los ratones desnudos, 89 por ciento presentó hipersegmentación de neutrófilos, mientras que sólo 10 por ciento de los heterocigóticos lo manifestó y no se observó en los ratones CD 1. En la población de linfocitos T totales CD3+ y en los CD8+ resultaron superiores los valores de los ratones et/et a los CD 1 (P < 0.05) y sin diferencia respecto a los et/+. Los valores en el hematocrito fueron mayores en los ratones et/et respecto de los CD 1(P < 0.05). En la cuantificación de proteínas plasmáticas, los ratones et/et presentaron menor densidad que los ratones CD 1. La fracción alfaglobulina del suero mostró diferencias en los ratones et/et, donde los machos presentan una concentración significativamente mayor (P < 0.05) a las hembras (8.94 por ciento ñ 1.81 vs 3.49 por ciento ñ 0.69). En el estudio del número de células linfoides en bazo, se observaron diferencias significativas en los ratones et/et que presentaron 43 células/50 m l, contra 97.5 en los ratones CD 1, mientras que los et/+ presentaron un valor intermedio sin significancia estadística. Con el análisis de resultados se concluye que los ratones et/et presentan dentro de sus características genéticas, una leucocitosis circulante con linfocitosis, monocitosis, eosinofilia y una linfopenia en bazo, así como la hipersegmentación de neutrófilos; lo anterior probablemente esté asociado a la hipersecreción adrenal que han descrito otros autores en los ratones et/et.


Assuntos
Animais , Ratos , Heterozigoto , Camundongos Nus , Valores de Referência , Sangue
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