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1.
Cell Host Microbe ; 32(7): 1103-1113.e6, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38838675

RESUMEN

Antibiotic treatment promotes the outgrowth of intestinal Candida albicans, but the mechanisms driving this fungal bloom remain incompletely understood. We identify oxygen as a resource required for post-antibiotic C. albicans expansion. C. albicans depleted simple sugars in the ceca of gnotobiotic mice but required oxygen to grow on these resources in vitro, pointing to anaerobiosis as a potential factor limiting growth in the gut. Clostridia species limit oxygen availability in the large intestine by producing butyrate, which activates peroxisome proliferator-activated receptor gamma (PPAR-γ) signaling to maintain epithelial hypoxia. Streptomycin treatment depleted Clostridia-derived butyrate to increase epithelial oxygenation, but the PPAR-γ agonist 5-aminosalicylic acid (5-ASA) functionally replaced Clostridia species to restore epithelial hypoxia and colonization resistance against C. albicans. Additionally, probiotic Escherichia coli required oxygen respiration to prevent a post-antibiotic bloom of C. albicans, further supporting the role of oxygen in colonization resistance. We conclude that limited access to oxygen maintains colonization resistance against C. albicans.


Asunto(s)
Candida albicans , Oxígeno , Candida albicans/efectos de los fármacos , Animales , Ratones , Oxígeno/metabolismo , PPAR gamma/metabolismo , Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Candidiasis/microbiología , Anaerobiosis , Hipoxia/metabolismo , Ratones Endogámicos C57BL , Estreptomicina/farmacología , Humanos , Ciego/microbiología , Mucosa Intestinal/microbiología , Mucosa Intestinal/metabolismo , Vida Libre de Gérmenes
2.
mBio ; 15(3): e0325223, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38289074

RESUMEN

Pericytes are located around blood vessels, in close contact with endothelial cells. We discovered that pericytes dampen pro-inflammatory endothelial cell responses. Endothelial cells co-cultured with pericytes had markedly reduced expression of adhesion molecules (PECAM-1 and ICAM-1) and proinflammatory cytokines (CCL-2 and IL-6) in response to bacterial stimuli (Brucella ovis, Listeria monocytogenes, or Escherichia coli lipopolysaccharide). Pericyte-depleted mice intraperitoneally inoculated with either B. ovis, a stealthy pathogen that does not trigger detectable inflammation, or Listeria monocytogenes, developed peritonitis. Further, during Citrobacter rodentium infection, pericyte-depleted mice developed severe intestinal inflammation, which was not evident in control mice. The anti-inflammatory effect of pericytes required connexin 43, as either chemical inhibition or silencing of connexin 43 abrogated pericyte-mediated suppression of endothelial inflammatory responses. Our results define a mechanism by which pericytes modulate inflammation during infection, which shifts our understanding of pericyte biology: from a structural cell to a pro-active player in modulating inflammation. IMPORTANCE: A previously unknown mechanism by which pericytes modulate inflammation was discovered. The absence of pericytes or blocking interaction between pericytes and endothelium through connexin 43 results in stronger inflammation, which shifts our understanding of pericyte biology, from a structural cell to a player in controlling inflammation.


Asunto(s)
Infecciones Bacterianas , Pericitos , Animales , Ratones , Ovinos , Pericitos/metabolismo , Células Endoteliales , Conexina 43/metabolismo , Conexina 43/farmacología , Inflamación , Infecciones Bacterianas/metabolismo
3.
J Dairy Sci ; 107(5): 2681-2689, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-37923204

RESUMEN

The potential use of carbon-based methodologies for drug delivery and reproductive biology in cows raises concerns about residues in milk and food safety. This study aimed to assess the potential of Fourier transform Raman spectroscopy and discriminant analysis using partial least squares (PLS-DA) to detect functionalized multiwalled carbon nanotubes (MWCNT) in bovine raw milk. Oxidized MWCNT were diluted in milk at different concentrations from 25.00 to 0.01 µg/mL. Raman spectroscopy measurements and PLS-DA were performed to identify low concentrations of MWCNT in milk samples. The PLS-DA model was characterized by the analysis of the variable importance in projection (VIP) scores. All the training samples were correctly classified by the model, resulting in no false-positive or false-negative classifications. For test samples, only one false-negative result was observed, for 0.01 µg/mL MWCNT dilution. The association between Raman spectroscopy and PLS-DA was able to identify MWCNT diluted in milk samples up to 0.1 µg/mL. The PLS-DA model was built and validated using a set of test samples and spectrally interpreted based on the highest VIP scores. This allowed the identification of the vibrational modes associated with the D and G bands of MWCNT, as well as the milk bands, which were the most important variables in this analysis.

4.
bioRxiv ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38106073

RESUMEN

Louis Pasteur's experiments on tartaric acid laid the foundation for our understanding of molecular chirality, but major questions remain. By comparing the optical activity of naturally-occurring tartaric acid with chemically-synthesized paratartaric acid, Pasteur realized that naturally-occurring tartaric acid contained only L-tartaric acid while paratartaric acid consisted of a racemic mixture of D- and L-tartaric acid. Curiously, D-tartaric acid has no known natural source, yet several gut bacteria specifically degrade D-tartaric acid. Here, we investigated the oxidation of monosaccharides by inflammatory reactive oxygen and nitrogen species. We found that this reaction yields an array of alpha hydroxy carboxylic acids, including tartaric acid isomers. Utilization of inflammation- derived D- and L-tartaric acid enhanced colonization by Salmonella Typhimurium and E. coli in murine models of gut inflammation. Our findings suggest that byproducts of inflammatory radical metabolism, such as tartrate and other alpha hydroxy carboxylic acids, create transient nutrient niches for enteric pathogens and other potentially harmful bacteria. Furthermore, this work illustrates that inflammatory radicals generate a zoo of molecules, some of which may erroneously presumed to be xenobiotics.

5.
Front Vet Sci ; 10: 1235299, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37701528

RESUMEN

This study included 47 free-ranging bats from the State of Minas Gerais, Brazil. Six bats (12.8%) had genital inflammatory lesions, and two of them (one Artibeus lituratus and one Glossophaga soricina, a frugivorous and a nectarivorous, respectively) were diagnosed with Brucella sp. infection through PCR, and antigens in intralesional macrophages were detected using immunohistochemistry.

6.
J Comp Pathol ; 204: 7-10, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37311267

RESUMEN

Tracheal luminal stenosis can cause clinical respiratory distress in wild birds. We describe a case of tracheal stenosis due to diffuse ossification with osteopetrosis of tracheal rings in a yellow-crowned parrot (Amazona ochrocephala) with a history of chronic respiratory distress and death after development of marked dyspnoea. An ante-mortem radiographic examination revealed that the tracheal rings were radiopaque and that there were multiple areas of osteopenic change in long bones. At necropsy, there was stenosis of the tracheal rings characterized by complete replacement of cartilage by thickened compact bone with osteopetrosis and bone necrosis. The clinical respiratory distress and death of the parrot were associated with tracheal luminal stenosis due to thickening of the tracheal rings by diffuse ossification with osteopetrosis.


Asunto(s)
Amazona , Enfermedades de las Aves , Osteopetrosis , Síndrome de Dificultad Respiratoria , Estenosis Traqueal , Animales , Estenosis Traqueal/veterinaria , Osteogénesis , Constricción Patológica/veterinaria , Osteopetrosis/veterinaria , Enfermedades de las Aves/diagnóstico , Síndrome de Dificultad Respiratoria/veterinaria
7.
J Comp Pathol ; 204: 17-22, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37321133

RESUMEN

There are a few studies on diseases of anteaters, but reports on reproductive lesions and neoplasms of these animals are scarce. This is the first report of a case of metastatic Sertoli cell tumour in a giant anteater (Myrmecophaga tridactyla). The animal had renal lesions associated with impaired renal function as indicated by serum biochemistry. Histopathological and immunohistochemical examinations provided a conclusive diagnosis of Sertoli cell tumour with metastasis to the liver, kidneys and lymph nodes.


Asunto(s)
Tumor de Células de Sertoli , Neoplasias Testiculares , Xenarthra , Masculino , Animales , Vermilingua , Tumor de Células de Sertoli/veterinaria , Animales de Zoológico , Neoplasias Testiculares/veterinaria
8.
bioRxiv ; 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37131682

RESUMEN

Antibiotic prophylaxis sets the stage for an intestinal bloom of Candida albicans , which can progress to invasive candidiasis in patients with hematologic malignancies. Commensal bacteria can reestablish microbiota-mediated colonization resistance after completion of antibiotic therapy, but they cannot engraft during antibiotic prophylaxis. Here we use a mouse model to provide a proof of concept for an alternative approach, which replaces commensal bacteria functionally with drugs to restore colonization resistance against C. albicans . Streptomycin treatment, which depletes Clostridia from the gut microbiota, disrupted colonization resistance against C. albicans and increased epithelial oxygenation in the large intestine. Inoculating mice with a defined community of commensal Clostridia species reestablished colonization resistance and restored epithelial hypoxia. Notably, these functions of commensal Clostridia species could be replaced functionally with the drug 5-aminosalicylic acid (5-ASA), which activates mitochondrial oxygen consumption in the epithelium of the large intestine. When streptomycin-treated mice received 5-ASA, the drug reestablished colonization resistance against C. albicans and restored physiological hypoxia in the epithelium of the large intestine. We conclude that 5-ASA treatment is a non-biotic intervention that restores colonization resistance against C. albicans without requiring the administration of live bacteria.

9.
J Vet Diagn Invest ; 35(3): 322-326, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36896670

RESUMEN

Tyzzer disease (TD) is a highly fatal condition of animals caused by Clostridium piliforme and characterized pathologically by enteritis, hepatitis, myocarditis, and occasionally encephalitis. Cutaneous lesions have been reported only rarely in animals with TD, and infection of the nervous system has not been described in cats, to our knowledge. We describe here neurologic and cutaneous infection by C. piliforme in a shelter kitten with systemic manifestations of TD and coinfection with feline panleukopenia virus. Systemic lesions included necrotizing typhlocolitis, hepatitis, myocarditis, and myeloencephalitis. The cutaneous lesions consisted of intraepidermal pustular dermatitis and folliculitis, with necrosis of keratinocytes and ulceration. Clostridial bacilli were identified within the cytoplasm of keratinocytes by fluorescence in situ hybridization, and a PCR assay was positive for C. piliforme. C. piliforme can infect keratinocytes leading to cutaneous lesions in cats with the location suggesting direct contact with contaminated feces as a route of infection.


Asunto(s)
Enfermedades de los Gatos , Infecciones por Clostridium , Miocarditis , Enfermedades Cutáneas Infecciosas , Gatos , Animales , Femenino , Hibridación Fluorescente in Situ/veterinaria , Miocarditis/veterinaria , Clostridium/genética , Infecciones por Clostridium/veterinaria , Celulitis (Flemón)/veterinaria , Enfermedades Cutáneas Infecciosas/veterinaria
10.
J Comp Pathol ; 200: 59-66, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36652777

RESUMEN

Platynosomosis is a parasitic disease caused by a trematode of the genus Platynosomum, a bile duct and gallbladder fluke that has been described in captive neotropical primates (New World primates; NWPs) and causes high morbidity and variable mortality. Although it is a major concern for ex-situ conservation of these animals, there are only a few studies of platynosomosis in free-ranging NWPs. Therefore, the aim of this study was to characterize platynosomosis in a free-ranging population of marmosets (Callithrix spp) from the Brazilian Atlantic Forest, focusing on the epidemiological and pathological aspects of the disease. A total of 1,001 marmosets were evaluated and on the basis of clinicoepidemiological data, histopathology, histochemistry and immunohistochemistry, we concluded that Platynosomum spp infection has a prevalence of 8.9% (confidence interval: 7.3-10.8%) in free-ranging marmosets, with a higher frequency in the Metropolitan Region of Rio de Janeiro. Infection was associated with fibrosing and proliferative cholangiohepatitis associated with biliary lithiasis (3.0% of cases) and secondary bacterial infections (14.6% of cases).


Asunto(s)
Infecciones Bacterianas , Litiasis , Trematodos , Infecciones por Trematodos , Animales , Callithrix/parasitología , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/veterinaria , Brasil/epidemiología , Prevalencia , Litiasis/veterinaria , Callitrichinae , Infecciones Bacterianas/veterinaria , Bosques
11.
Microbiome ; 10(1): 200, 2022 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-36434690

RESUMEN

BACKGROUND: Intestinal inflammation disrupts the microbiota composition leading to an expansion of Enterobacteriaceae family members (dysbiosis). Associated with this shift in microbiota composition is a profound change in the metabolic landscape of the intestine. It is unclear how changes in metabolite availability during gut inflammation impact microbial and host physiology. RESULTS: We investigated microbial and host lactate metabolism in murine models of infectious and non-infectious colitis. During inflammation-associated dysbiosis, lactate levels in the gut lumen increased. The disease-associated spike in lactate availability was significantly reduced in mice lacking the lactate dehydrogenase A subunit in intestinal epithelial cells. Commensal E. coli and pathogenic Salmonella, representative Enterobacteriaceae family members, utilized lactate via the respiratory L-lactate dehydrogenase LldD to increase fitness. Furthermore, mice lacking the lactate dehydrogenase A subunit in intestinal epithelial cells exhibited lower levels of inflammation in a model of non-infectious colitis. CONCLUSIONS: The release of lactate by intestinal epithelial cells during gut inflammation impacts the metabolism of gut-associated microbial communities. These findings suggest that during intestinal inflammation and dysbiosis, changes in metabolite availability can perpetuate colitis-associated disturbances of microbiota composition. Video Abstract.


Asunto(s)
Colitis , Microbioma Gastrointestinal , Ratones , Animales , Disbiosis , Escherichia coli/metabolismo , Ácido Láctico/metabolismo , Lactato Deshidrogenasa 5 , Ratones Endogámicos C57BL , Inflamación/patología , Colitis/patología , Enterobacteriaceae/metabolismo
12.
mBio ; 13(6): e0273322, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36286551

RESUMEN

Capsular polysaccharides are common virulence factors of extracellular, but not intracellular bacterial pathogens, due to the antiphagocytic properties of these surface structures. It is therefore paradoxical that Salmonella enterica subspecies enterica serovar Typhi, an intracellular pathogen, synthesizes a virulence-associated (Vi) capsule, which exhibits antiphagocytic properties. Here, we show that the Vi capsular polysaccharide has different functions when S. Typhi interacts with distinct subsets of host phagocytes. The Vi capsular polysaccharide allowed S. Typhi to selectively evade phagocytosis by human neutrophils while promoting human macrophage phagocytosis. A screen of C-type lectin receptors identified human DC-SIGN as the receptor involved in macrophage binding and phagocytosis of capsulated S. Typhi. Consistent with the anti-inflammatory activity of DC-SIGN, purified Vi capsular polysaccharide reduced inflammatory responses in macrophages. These data suggest that binding of the human C-type lectin receptor DC-SIGN by the Vi capsular polysaccharide contributes to the pathogenesis of typhoid fever. IMPORTANCE Salmonella enterica subspecies enterica serovar Typhi is the causative agent of typhoid fever. The recent emergence of S. Typhi strains which are resistant to antibiotic therapy highlights the importance of vaccination in managing typhoid fever. The virulence-associated (Vi) capsular polysaccharide is an effective vaccine against typhoid fever, but the role the capsule plays during pathogenesis remains incompletely understood. Here, we identify the human C-type lectin receptor DC-SIGN as the receptor for the Vi capsular polysaccharide. Binding of capsulated S. Typhi to DC-SIGN resulted in phagocytosis of the pathogen by macrophages and induction of an anti-inflammatory cytokine response. Thus, the interaction of the Vi capsular polysaccharide with human DC-SIGN contributes to the pathogenesis of typhoid fever and should be further investigated in the context of vaccine development.


Asunto(s)
Salmonella typhi , Fiebre Tifoidea , Humanos , Fiebre Tifoidea/microbiología , Polisacáridos Bacterianos/metabolismo , Lectinas Tipo C/metabolismo , Fagocitosis , Macrófagos/metabolismo
13.
J Comp Pathol ; 198: 29-32, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36116889

RESUMEN

Rabies is a severe viral zoonosis of mammals and causes irreversible neurological damage. We describe the clinical presentation and anatomopathological lesions of rabies in a captive lowland tapir (Tapirus terrestris) in Bauru, São Paulo State, Brazil. The clinical course of the disease lasted 6 days and was characterized by progressive neurological deterioration and death. The main anatomopathological findings were non-suppurative encephalitis and presence of Negri bodies within neurons. Direct immunofluorescence and mouse inoculation tests were positive for rabies virus. This is the first report of rabies in a lowland tapir and highlights the importance of disease prevention under managed care and continuous control measures in urbanized environments.


Asunto(s)
Rabia , Enfermedades de los Roedores , Animales , Brasil , Ratones , Perisodáctilos , Rabia/veterinaria
14.
J Comp Pathol ; 186: 62-68, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34340805

RESUMEN

We report the clinicopathological manifestations of canine adenovirus type 1 (CAV 1) infection in captive-born naturally infected maned wolves (Chrysocyon brachyurus). Two 3-month-old maned wolves presented with lethargy, emesis, dehydration, pallor, hypothermia, leucocytosis, neutrophilia, lymphopaenia and thrombocytopaenia. One of the puppies died shortly after admission, with gross changes that included marked gastrointestinal petechiae, splenomegaly, hepatomegaly and pulmonary haemorrhage. Histologically, large eosinophilic intranuclear body inclusions were found in the liver and kidneys. The other wolf had elevated alkaline phosphatase, alanine aminotransferase and creatine kinase activities, and later developed anaemia, hypoalbuminaemia, bilirubinaemia, bilirubinuria, haematuria and proteinuria. Ultrasound demonstrated hepatomegaly, splenomegaly, inguinal lymphadenomegaly and lesions suggestive of gastritis and enteritis. Despite supportive treatment, the animal died. At necropsy, there was icterus, subcutaneous oedema in the inguinal region and hindlimbs, subchondral haemorrhage of articular cartilage of the femoral-tibial-patellar and tarsal joints of both hindlimbs, lymphadenomegaly, bronchopneumonia, hepatomegaly and petechiae in the gastrointestinal mucosa. Microscopically, there was a severe necrotizing hepatitis with intranuclear viral inclusions, fibrinous-necrotizing splenitis, non-suppurative meningoencephalitis and interstitial nephritis. A quantitative PCR test for CAV 1 using DNA extracted from peripheral blood was positive. The clinicopathological findings are similar to those of CAV 1 infection in dogs and other canids.


Asunto(s)
Anemia , Canidae , Hepatitis Infecciosa Canina , Adenovirus Caninos , Anemia/veterinaria , Animales , Canidae/virología , Perros , Hemorragia/veterinaria
15.
Vet Pathol ; 58(5): 766-794, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34282984

RESUMEN

Standardization of tumor assessment lays the foundation for validation of grading systems, permits reproducibility of oncologic studies among investigators, and increases confidence in the significance of study results. Currently, there is minimal methodological standardization for assessing tumors in veterinary medicine, with few attempts to validate published protocols and grading schemes. The current article attempts to address these shortcomings by providing standard guidelines for tumor assessment parameters and protocols for evaluating specific tumor types. More detailed information is available in the Supplemental Files, the intention of which is 2-fold: publication as part of this commentary, but more importantly, these will be available as "living documents" on a website (www.vetcancerprotocols.org), which will be updated as new information is presented in the peer-reviewed literature. Our hope is that veterinary pathologists will agree that this initiative is needed, and will contribute to and utilize this information for routine diagnostic work and oncologic studies. Journal editors and reviewers can utilize checklists to ensure publications include sufficient detail and standardized methods of tumor assessment. To maintain the relevance of the guidelines and protocols, it is critical that the information is periodically updated and revised as new studies are published and validated with the intent of providing a repository of this information. Our hope is that this initiative (a continuation of efforts published in this journal in 2011) will facilitate collaboration and reproducibility between pathologists and institutions, increase case numbers, and strengthen clinical research findings, thus ensuring continued progress in veterinary oncologic pathology and improving patient care.


Asunto(s)
Neoplasias , Patología Veterinaria , Animales , Neoplasias/diagnóstico , Neoplasias/veterinaria , Reproducibilidad de los Resultados
16.
Braz J Microbiol ; 52(4): 1745-1753, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34251610

RESUMEN

Historically, clinical microbiological laboratories have often relied on isolation of pure cultures and phenotypic testing to identify microorganisms. These clinical tests are often based on specific biochemical reactions, growth characteristics, colony morphology, and other physiological aspects. The features used for identification in clinical laboratories are highly conserved and specific for a given group of microbes. We speculate that these features might be the result of evolutionary selection and thus may reflect aspects of the life cycle of the organism and pathogenesis. Indeed, several of the metabolic pathways targeted by diagnostic tests in some cases may represent mechanisms for host colonization or pathogenesis. Examples include, but are not restricted to, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella enterica, Shigella spp., and enteroinvasive Escherichia coli (EIEC). Here, we provide an overview of how some common tests reflect molecular mechanisms of bacterial pathogenesis.


Asunto(s)
Infecciones Bacterianas , Disentería Bacilar , Adaptación al Huésped , Bacterias/inmunología , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/microbiología , Infecciones Bacterianas/patología , Disentería Bacilar/diagnóstico , Disentería Bacilar/microbiología , Disentería Bacilar/fisiopatología , Humanos , Laboratorios Clínicos
17.
Elife ; 102021 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-34085924

RESUMEN

The composition of gut-associated microbial communities changes during intestinal inflammation, including an expansion of Enterobacteriaceae populations. The mechanisms underlying microbiota changes during inflammation are incompletely understood. Here, we analyzed previously published metagenomic datasets with a focus on microbial hydrogen metabolism. The bacterial genomes in the inflamed murine gut and in patients with inflammatory bowel disease contained more genes encoding predicted hydrogen-utilizing hydrogenases compared to communities found under non-inflamed conditions. To validate these findings, we investigated hydrogen metabolism of Escherichia coli, a representative Enterobacteriaceae, in mouse models of colitis. E. coli mutants lacking hydrogenase-1 and hydrogenase-2 displayed decreased fitness during colonization of the inflamed cecum and colon. Utilization of molecular hydrogen was in part dependent on respiration of inflammation-derived electron acceptors. This work highlights the contribution of hydrogenases to alterations of the gut microbiota in the context of non-infectious colitis.


Asunto(s)
Ciego/microbiología , Colitis/inducido químicamente , Colitis/microbiología , Colon/microbiología , Infecciones por Escherichia coli/microbiología , Escherichia coli/metabolismo , Microbioma Gastrointestinal , Hidrógeno/metabolismo , Animales , Ciego/metabolismo , Ciego/patología , Colitis/metabolismo , Colitis/patología , Colon/metabolismo , Colon/patología , Bases de Datos Genéticas , Sulfato de Dextran , Modelos Animales de Enfermedad , Disbiosis , Escherichia coli/genética , Escherichia coli/crecimiento & desarrollo , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/patología , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Femenino , Humanos , Hidrogenasas/genética , Hidrogenasas/metabolismo , Interleucina-10/genética , Interleucina-10/metabolismo , Masculino , Metagenoma , Metagenómica , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Piroxicam
18.
Front Vet Sci ; 8: 594291, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33738302

RESUMEN

Canine brucellosis is an infectious and zoonotic disease caused by Brucella canis, which has been reported worldwide, and is a major public health concern due to close contact between dogs and humans. In dogs, canine brucellosis manifests with abortion outbreaks, reproductive failure, enlargement of lymph nodes, and occasionally affects the osteoarticular system, although the occurrence of asymptomatic infections in dogs are not uncommon. In humans, the disease is associated with a febrile syndrome, commonly with non-specific symptoms including splenomegaly, fatigue, and weakness. Infection of dogs occurs mostly by the oronasal route when in contact with contaminated tissues such as aborted fetuses, semen, urine, and vaginal secretions. In humans, contact with contaminated fluids from infected dogs is an important source of infection, and it is an occupational risk for veterinarians, breeders, laboratory workers, among other professionals who deal with infected animals or biological samples. The diagnosis in dogs is largely based on serologic methods. However, serologic diagnosis of canine brucellosis remains very challenging due to the low accuracy of available tests. Molecular diagnostic methods have been increasingly used in the past few years. Treatment of infected dogs is associated with a high frequency of relapse, and should be employed only in selected cases. Currently there are no commercially available vaccines for prevention of canine brucellosis. Therefore, development of novel and improved diagnostic methods as well as the development of efficacious and safe vaccination protocols are needed for an effective control of canine brucellosis and its associated zoonotic risk.

19.
Int J Biol Macromol ; 176: 567-577, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33581203

RESUMEN

Listeria monocytogenes is a cause of infectious food-borne disease in humans, characterized by neurological manifestations, abortion, and neonatal septicemia. It is intracellular bacterium, which limits the development of protective inactivated vacines. Adjuvants capable of stimulating cellular immune response are important tools for developing novel vaccines against intracellular bacteria. The aim of this study was to evaluate the vaccine potential of L. monocytogenes inactivated by gamma irradiation (KLM-γ) encapsulated in alginate microcapsules associated or not with chitosan against listeriosis in the murine model. At the fourth day after challenge there was a reduction in bacterial recovery in mice vaccinated with KLM-γ encapsulated with alginate or alginate-chitosan, with lower bacterial loads in the spleen (10 fold) and liver (100 fold) when compared to non-vaccinated mice. In vitro stimulation of splenocytes from mice vaccinated with alginate-chitosan-encapsulated KLM-γ resulted in lymphocyte proliferation, increase of proportion of memory CD4+ and CD8+ T cell and production of IL-10 and IFN-γ. Interestingly, the group vaccinated with alginate-chitosan-encapsulated KLM-γ had increased survival to lethal infection with lower L. monocytogenes-induced hepatic inflammation and necrosis. Therefore, KLM-γ encapsulation with alginate-chitosan proved to have potential for development of novel and safe inactivated vaccine formulations against listeriosis.


Asunto(s)
Alginatos , Vacunas Bacterianas , Quitosano , Rayos gamma , Listeria monocytogenes , Listeriosis , Alginatos/química , Alginatos/farmacología , Animales , Vacunas Bacterianas/química , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/farmacología , Quitosano/química , Quitosano/farmacología , Modelos Animales de Enfermedad , Femenino , Listeria monocytogenes/química , Listeria monocytogenes/inmunología , Listeriosis/inmunología , Listeriosis/prevención & control , Ratones , Ratones Endogámicos BALB C , Vacunas de Productos Inactivados/química , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/farmacología
20.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1487626

RESUMEN

ABSTRACT: Equine coital exanthema is a venereal infectious disease poorly reported in horses in Brazil and was never described in the northeastern region of the country. This work aims to describe the clinical and pathological aspects of an outbreak of equine coital exanthema caused by equid alphaherpesvirus 3, occurred in a herd of horses at the semiarid region of the State of Rio Grande do Norte. Main clinical signs consisted of anorexia, hiporexia, fibrinous or purulent secretion in the penis mucosa and vagina. Two mares presented mild to minimal lesions that consisted of scars in the mucosa of the vagina and in the perivulvar region. In a stallion the disease consisted of severe, multifocal, umbilicated-exanthematous ulcers of approximately 1cm in diameter on the penis mucosa. Other areas where ulcers and crusts were focally observed included the skin of the scrotum and on the lips and mucocutaneous junctions of the oral cavity. Histologically, the main lesion consisted of multifocal severe ulcerative and fibrinous necrotizing balanoposthitis and mild multifocal necrotizing, lymphocytic dermatitis in the lips and scrotum. The equide alphaherpesvirus 3 DNA was amplified in blood samples and penis mucosa using the PCR technique. This is the first report of molecular diagnosis of equine coital exanthema affecting horses in northeastern Brazil. Further studies should be carried out in order to investigate the epidemiology and the importance of this herpetic disease in the country.


RESUMO: O exantema coital equino é uma doença infecciosa venérea pouco relatada em equinos no Brasil e nunca descrita na região Nordeste do país. Este trabalho tem como objetivo descrever os aspectos clínicos e patológicos de um surto de exantema coital equino causado pelo alphaherpesvirus equídeo 3, que ocorreu em um haras na região semiárida do Estado do Rio Grande do Norte. Os principais sinais clínicos consistiram em anorexia, hiporexia, secreção fibrinosa ou purulenta na mucosa do pênis e vagina. Duas éguas apresentavam lesões discretas que consistiam em cicatrizes na mucosa da vagina e na região perivulvar. Em um garanhão, a doença consistia em úlceras umbilicadas-exantematosas severas, multifocais, de aproximadamente 1 cm de diâmetro na mucosa do pênis. Outras áreas onde úlceras e crostas foram observadas focalmente incluíram a pele do escroto, lábios e junções mucocutâneas da cavidade oral. Histologicamente, as principais lesões consistiam em balanopostite multifocal ulcerativa e necrosante fibrinosa grave e dermatite linfocítica necrosante multifocal leve nos lábios e escroto. O DNA do alphaherpesvirus equídeo tipo 3 foi amplificado em amostras de sangue e mucosa do pênis pela técnica de PCR. Este é o primeiro relato de diagnóstico molecular de exantema coital equino afetando cavalos no nordeste do Brasil. Novos estudos devem ser realizados a fim de investigar a epidemiologia e a importância dessa doença herpética no país.

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