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1.
Liver Transpl ; 25(9): 1375-1386, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121085

RESUMO

Organ transplantation is the treatment of choice against terminal and irreversible organ failure. Optimal preservation of the graft is crucial to counteract cold ischemia effects. As we developed an N,N-bis-2-hydroxyethyl-2-aminoethanesulfonic acid-gluconate-polyethylene glycol (BGP)-based solution (hypothermic machine perfusion [HMP]), we aimed to analyze the use of this solution on static cold storage (SCS) of rat livers for transplantation as compared with the histidine tryptophan ketoglutarate (HTK) preservation solution. Livers procured from adult male Sprague Dawley rats were preserved with BGP-HMP or HTK solutions. Liver total water content and metabolites were measured during the SCS at 0°C for 24 hours. The function and viability of the preserved rat livers were first assessed ex vivo after rewarming (90 minutes at 37°C) and in vivo using the experimental model of reduced-size heterotopic liver transplantation. After SCS, the water and glycogen content in both groups remained unchanged as well as the tissue glutathione concentration. In the ex vivo studies, livers preserved with the BGP-HMP solution were hemodynamically more efficient and the O2 consumption rate was higher than in livers from the HTK group. Bile production and glycogen content after 90 minutes of normothermic reperfusion was diminished in both groups compared with the control group. Cellular integrity of the BGP-HMP group was better, and the histological damage was reversible. In the in vivo model, HTK-preserved livers showed a greater degree of histological injury and higher apoptosis compared with the BGP-HMP group. In conclusion, our results suggest a better role of the BGP-HMP solution compared with HTK in preventing ischemia/reperfusion injury in the rat liver model.

2.
Avian Pathol ; 48(5): 460-469, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31106577

RESUMO

The aim of this study was to examine the histopathological and immunohistochemical changes caused by natural and experimentally-induced Ornithobacterium rhinotracheale infection in the respiratory system of chickens. To this end, three different studies were carried out. The first was a retrospective study of 82 field cases with respiratory disorders compatible with O. rhinotracheale infection. The bacterium was immunohistochemically detected in the lungs in 48 of 82 field cases, and 50 ß-haemolytic (BH) and non-haemolytic (NH) strains were isolated. In the second study, an experimental model of the disease was created using 3-week-old broiler chickens, to identify possible differences of pathogenicity between the BH and NH isolates by the intravenous (IV) and intratracheal (IT) inoculation routes (IR). The group challenged with the NH isolate showed more severe lung lesions than the group challenged with the BH isolate at 7-days postinoculation (p.i.). The 14-day p.i. groups challenged with either the BH or NH isolates by the IT or IV IR had a higher histologic grade of pulmonary and hepatic lesions and a higher total histologic grade of lesions suggesting more severe pathology with longer time of exposure. A direct association between the inoculation routes and the organs affected was shown. Finally, a slaughterhouse study was carried out from October 2014 to May 2015, in which the histologic grade of lesions was significantly higher in immunohistochemically positive for O. rhinotracheale lungs of dead-on-arrival chickens.

3.
Vet Pathol ; 54(4): 620-628, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28622490

RESUMO

The purpose of this study was to follow the progression of gross and histologic lesions and apoptosis events in Lawsonia intracellularis-infected enterocytes through the course of the disease, proliferative enteropathy (PE). Thirty 5-week-old pigs were divided into 2 groups: 20 challenged and 10 control animals. Groups of 3 pigs, 2 challenged and 1 control, were euthanized at 1, 3, 5, 8, 11, 15, 19, 24, 29, and 35 days after inoculation. Complete necropsies were performed with gross evaluation. Tissue samples from different sites of the gastrointestinal tract and other visceral organs were collected for routine histologic staining and for immunohistochemistry (IHC) for L. intracellularis. In addition, caspase-3, terminal deoxyuridine nick-end labeling assay, and electron microscopy were performed in ileum samples. Macroscopic and histologic lesions suggestive of PE were first detected 11 days after infection and continued through day 24. L. intracellularis antigen was first detected in the intestine by IHC on day 5 after inoculation, and the bacterium was first detected by transmission electron microscopy on day 15. Positive IHC staining for [L. intracellularis] and enterocyte proliferation, but no gross lesion, were detected on day 29. All 3 pigs euthanized on day 35 were grossly and histologically normal and IHC negative. Hyperplastic crypts in challenge pigs had more apoptotic cells on days 15, 19, and 24 postinfection ( P < .05) compared to control pigs. Our results demonstrated the progression of lesions and infection by L. intracellularis and that inhibition of enterocyte apoptosis is not involved in the pathogenesis of proliferative enteropathy.


Assuntos
Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria) , Doenças dos Suínos/microbiologia , Animais , Apoptose , Estudos de Casos e Controles , Infecções por Desulfovibrionaceae/patologia , Progressão da Doença , Enterócitos/microbiologia , Enterócitos/patologia , Feminino , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/patologia , Íleo/patologia , Íleo/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão/veterinária , Suínos , Doenças dos Suínos/patologia
4.
Influenza Other Respir Viruses ; 7 Suppl 4: 10-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24224814

RESUMO

BACKGROUND: Influenza A viruses (IAV) are important pathogens responsible for economic losses in the swine industry and represent a threat to public health. In Argentina, clinical, pathological, and virological findings suggest that IAV infection is widespread among pig farms. In addition, several subtypes of IAV, such as pH1N1, H3N2, δ1H1N1, and δ2H1N2, have been reported. OBJECTIVES: To evaluate the infection patterns of influenza virus in nine pig farms in Argentina. METHODS: Clinical, serological, pathological, and virological cross-sectional studies were conducted. RESULTS: Clinical and pathological results were characteristic of endemic influenza infection in eight of the nine farms studied. By rRT-PCR, six of the nine farms were positive to influenza. Five IAV were obtained. Genome analysis determined that four of the isolations were pH1N1 and that the remaining one was a reassortant human origin H3N2 virus containing pandemic internal genes. Serological results showed that all farms were positive to influenza A antibodies. Moreover, the hemagglutination inhibition test showed that infection with viruses containing HA's from different subtypes (pH1, δ1H1, δ2H1, and H3) is present among the farms studied and that coinfections with two or more subtypes were present in 80.5% of positive pigs. CONCLUSIONS: Because vaccines against IAV are not licensed in Argentina, these results reflect the situation of IAV infection in non-vaccinated herds. This study provides more information about the circulation and characteristics of IAV in a poorly surveyed region. This study provides more data that will be used to evaluate the tools necessary to control this disease.


Assuntos
Anticorpos Antivirais/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/imunologia , Doenças dos Suínos/patologia , Animais , Argentina/epidemiologia , Estudos Transversais , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A Subtipo H3N2/genética , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia
5.
Acta Gastroenterol Latinoam ; 41(2): 129-36, 2011 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-21894726

RESUMO

INTRODUCTION: The intestine is a highly sensitive tissue to ischemia-reperfusion (IR) injury that will early respond increasing its permeability. Later this response is translated in morphologic and histological changes that reveal the degree of damage. The heterotopic intestinal transplantation model in rats allows to evaluate the evolution of intestinal tissue injury after ischemia-reperfusion without affecting the long survival rate. OBJECTIVE: The aim of this paper is to establish a relationship between the ischemic reperfusion injury with the long-term survival METHODS: Ten intestinal transplants were analyzed in adult, Wistar, inbred, male rats. Light microscopical examination was performed on intestine graft: 1) immediately post-dissection, 2) at the end of cold isquemia, 3) 30 min, 4) 48hs and 5) 5 days post-transplant procedure, respectively. Biopsies were reported according to Park's classification and extension of staining using immunohistochemestry to malondialdehyde (MDA) products. RESULTS: The Park's classification indexes reported in samples were 1) 0,57 +/- 1,13 (N=10); 2) 2,71 +/- 1,25 (N=10); 3) 4,14 +/- 0,89 (N=10); 4) 1,0 +/- 0,81 (N=7); 5) 0 (N=7). The highest levels of immunohistochemical detection of MDA were observed thirty minutes post-reperfusion (extension of staining between 51% to 75%). Three animals died when they were sampled at 48 hours, and the biopsies had Park's classification > or = 4 at 30 minutes post-reperfusion and endotoxemic signology. CONCLUSIONS: The highest degree of mucosal damage was observed immediately post-reperfusion. At 48hs the graft tended to be normalized Failure to repair the immediately I-R injury signficantly affects the long term survival.


Assuntos
Intestinos/transplante , Traumatismo por Reperfusão/mortalidade , Animais , Modelos Animais de Doenças , Intestinos/irrigação sanguínea , Intestinos/patologia , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Índice de Gravidade de Doença , Taxa de Sobrevida , Fatores de Tempo
6.
J Gen Virol ; 92(Pt 12): 2871-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21849519

RESUMO

Sporadic outbreaks of human H3N2 influenza A virus (IAV) infections in swine populations have been reported in Asia, Europe and North America since 1970. In South America, serological surveys in pigs indicate that IAVs of the H3 and H1 subtypes are currently in circulation; however, neither virus isolation nor characterization has been reported. In November 2008, an outbreak of respiratory disease in pigs consistent with swine influenza virus (SIV) infection was detected in Argentina. The current study describes the clinical epidemiology, pathology, and molecular and biological characteristics of the virus. Phylogenetic analysis revealed that the virus isolate shared nucleotide identities of 96-98 % with H3N2 IAVs that circulated in humans from 2000 to 2003. Antigenically, sera from experimentally inoculated animals cross-reacted mainly with non-contemporary human-origin H3N2 influenza viruses. In an experimental infection in a commercial swine breed, the virus was of low virulence but was transmitted efficiently to contact pigs and caused severe disease when an infected animal acquired a secondary bacterial infection. This is the first report of a wholly human H3N2 IAV associated with clinical disease in pigs in South America. These studies highlight the importance of two-way transmission of IAVs and SIVs between pigs and humans, and call for enhanced influenza surveillance in the pig population worldwide.


Assuntos
Vírus da Influenza A Subtipo H3N2/patogenicidade , Influenza Humana/transmissão , Influenza Humana/virologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/veterinária , Animais , Argentina/epidemiologia , Surtos de Doenças , Humanos , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/epidemiologia , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Filogenia , Filogeografia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Replicação Viral
7.
Influenza Other Respir Viruses ; 5(6): 409-12, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21668680

RESUMO

In this report, we describe the occurrence of two novel swine influenza viruses (SIVs) in pigs in Argentina. These viruses are the result of two independent reassortment events between the H1N1 pandemic influenza virus (H1N1pdm) and human-like SIVs, showing the constant evolution of influenza viruses at the human-swine interface and the potential health risk of H1N1pdm as it appears to be maintained in the swine population. It must be noted that because of the lack of information regarding the circulation of SIVs in South America, we cannot discard the possibility that ancestors of the H1N1pdm or other SIVs have been present in this part of the world. More importantly, these findings suggest an ever-expanding geographic range of potential epicenters of influenza emergence with public health risks.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Argentina , Vírus da Influenza A Subtipo H1N1/classificação , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Infecções por Orthomyxoviridae/virologia , Pandemias , Vírus Reordenados/classificação , Vírus Reordenados/genética , Vírus Reordenados/fisiologia , Suínos
8.
ISRN Vet Sci ; 2011: 560905, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23738099

RESUMO

Porcine circovirus type 2 (PCV-2) has been associated with syndromes grouped by the term porcine circovirus associated diseases (PCVAD). The PCV-2 isolates have been grouped into two major groups or genotypes according to their nucleotide sequence of whole genomes and/or ORF-2: PCV-2b, which have, in turn, been subdivided into three clusters (1A-1C), and PCV-2a, which has been subdivided into five clusters (2A-2E). In the present study, we obtained 16 sequences of PCV-2 from different farms from 2003 to 2008, from animals with confirmatory diagnosis of PCVAD. Since results showed an identity of 99.8% among them, they were grouped within a common cluster 1A-B. This preliminary study suggests a stable circulation of PCV-2b among the Argentinean pig population.

10.
Foodborne Pathog Dis ; 6(8): 965-72, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19642916

RESUMO

The aim of this surveillance was to study both Salmonella spp. shedding patterns and the time course of serological response in farrow-to-finish reared pigs from a subclinically infected farm. Antimicrobial resistance profile, molecular subtyping, and the relationship among the isolates were determined by pulsed-field gel electrophoresis (PFGE). A farrow-to-finish farm of 6000 sows, with a history of Salmonella Typhimurium septicemia, was selected. A longitudinal bacteriological and serological study was conducted in 25 sows before farrowing (M/S1) and in 50 offspring at 21 (M/S2), 35 (M/S3), 65 (M/S4), 86 (M/S5), 128 (M/S6), and 165 (M/S7) days of age. Serum antibodies were tested using Herdcheck((R)) Swine Salmonella antibody test kit (Idexx Laboratories, ME). Bacteria were isolated from pooled fecal samples. Suspected isolates were confirmed by conventional biochemical assays, and those identified as Salmonella spp. were serotyped. A variation between seropositive percentages and positive fecal samples was observed. Serologically positive pigs decreased from S1 to S4, and subsequently increased from S4 to S7. The percentages of fecal positive culture increased from M1 to M3, and then declined in M4, increased in M5, and were negative in M6 and M7. In the study three serovars, Salmonella 3,10:e,h:-, Salmonella Muenster, and Salmonella Bovismorbificans, were identified with low pathogenicity for swine. Three multidrug resistance strains (one belonged to Salmonella 3,10:e,h:- and two belonged to Salmonella Muenster) were found. PFGE results showed three different but closely related patterns among the 13 isolates of Salmonella Bovismorbificans, and two patterns for the three Salmonella Muenster and Salmonella 3,10:e,h:- isolates. This longitudinal study established critical points of Salmonella spp. infection in the farm and the production stages, where appropriate control measures must be taken. PFGE showed clonal relationships in each serovar. Antibiotic resistance profiles should be periodically included due to public health concerns.


Assuntos
Farmacorresistência Bacteriana/genética , Salmonelose Animal/microbiologia , Salmonella enterica , Doenças dos Suínos/microbiologia , Envelhecimento , Criação de Animais Domésticos/métodos , Animais , Argentina/epidemiologia , Derrame de Bactérias , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Eletroforese em Gel de Campo Pulsado/veterinária , Fezes/microbiologia , Feminino , Variação Genética , Estudos Longitudinais , Masculino , Filogenia , Reto/microbiologia , Salmonelose Animal/epidemiologia , Salmonelose Animal/prevenção & controle , Salmonella enterica/classificação , Estudos Soroepidemiológicos , Sorotipagem/veterinária , Suínos , Doenças dos Suínos/epidemiologia , Fatores de Tempo
11.
Emerg Infect Dis ; 14(3): 484-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18325268

RESUMO

We describe an outbreak of vomiting, wasting, and encephalomyelitis syndrome in piglets in Argentina, caused by porcine hemagglutinating encephalomyelitis coronavirus (PHE-CoV) infection. Diagnosis was made by epidemiologic factors, pathologic features, immunohistochemistry, reverse transcription-PCR, and genomic sequencing. This study documents PHE-CoV infection in South America.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/isolamento & purificação , Doenças dos Suínos/virologia , Animais , Argentina/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Surtos de Doenças/veterinária , Suínos , Doenças dos Suínos/epidemiologia
12.
Pesqui. vet. bras ; 24(1): 1-5, jan.-mar. 2004. ilus, tab
Artigo em Inglês | LILACS | ID: lil-364147

RESUMO

A eperitrozoonose suína é uma doença hemotrópica causada por Eperitrozoon suis, atualmente denominado Mycoplasma suis, uma bactéria extracelular que, aparentemente, adere à membrana dos eritrócitos suínos, induzindo sua deformação e lesionando-os. O presente trabalho busca estabelecer os aspectos estruturais e ultra-estruturais, pouco conhecidos, deste microorganismo. O estudo ultra-estrutural revelou a presença de estruturas correspondentes a túbulos disseminados no soma bacteriano. Observou-se também uma separação variável entre a membrana do microorganismo e a parede do eritrócito. O estudo morfométrico e a localização de M. suis pode permitir especulação sobre seu mecanismo de ação.


Assuntos
Animais , Masculino , Feminino , Infecções por Mycoplasma , Suínos
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