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1.
Animals (Basel) ; 11(2)2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33572479

RESUMO

There are numerous cases when conventional spermiogram parameters are all within an acceptable range but boar subfertility persists. The total sperm nuclear DNA fragmentation index (tDFI) is a trait related to fertility and prolificacy problems that is not routinely evaluated in commercial AI boars. The aim of this research was to study the effect of the photoperiod, season and reproductive age of the boar on tDFI (measured by SCSA) of 1279 ejaculates from 372 different boars belonging to 6 different breeds located in 6 AI studs in Spain. tDFI data ranged from 0.018% to 20.1%. Although there was a significant single boar effect in the tDFI occurrence, a negative correlation between the tDFI and the age of the boar was found (p < 0.001). tDFI would decrease due to aging of the boar 0.66% each year old within the observed age range. After including age as a covariate in the ANCOVA, no differences were found in tDFI between photoperiods when the sperm collection date was evaluated. However, when the date of the production of semen in the testis was evaluated, the total percentage of spermatozoa with fragmented nuclear DNA was 1.46% higher in the increasing photoperiod in comparison to the decreasing photoperiod (p < 0.0001). On the other hand, for both dates, the lowest tDFI values corresponded to minimum day length for decreasing photoperiod phase (autumn), while the highest tDFI values were found in summer (maximum day length for decreasing photoperiod phase).

2.
Reprod Domest Anim ; 55(9): 1202-1209, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32614487

RESUMO

Reproduction in swine is mostly carried out through artificial insemination (AI). For this purpose, AI studs collect the ejaculates, analyse the sperm quality, dilute and package to produce seminal doses and ship them to sow farms to carry out the AI. Temperature is controlled during the process to avoid sperm damage. Semen is diluted in the extender in a one-step or a two-step process where the second can be isothermic (approximately 32°C) or hypothermic (room temperature 21-22°C). Both techniques are currently performed, and the latter could reduce time and costs, but the literature available comparing the processes is scarce and presents discrepancies. To date, there are no studies about its impact in fertility. This study compared hypothermic two-step dilution (HTSD) and isothermic two-step dilution (ITSD) in laboratory and field trial to elucidate whether HTSD has any effect. Ejaculates from 72 boars in nine AI studs were split and processed with both techniques using a high-performance extender and evaluated in laboratory. Four farms inseminated 345 sows with samples of four of these AI studs, and their fertility and prolificacy were registered. Results show no significant differences between doses prepared by HTSD and ITSD technique, having no impact in laboratory results (percentage of motile sperm, short hypoosmotic swelling test (sHOST) and short osmotic resistance test (sORT), viable sperm, damaged acrosomes, sperm under early apoptosis, high mitochondrial membrane potential (p > .1), fertility (92.2% versus 94.1%, p = .45) or farrowing rate (15.8 ± 0.3 versus 16.1 ± 0.3 p = .46). In conclusion, our results suggest that HTSD of semen on extender could be safely implemented in AI studs under the conditions tested.


Assuntos
Fertilidade , Inseminação Artificial/veterinária , Espermatozoides/fisiologia , Animais , Feminino , Inseminação Artificial/métodos , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Sus scrofa
3.
Cell Microbiol ; 21(7): e13019, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30817085

RESUMO

Brucellosis is a zoonosis caused by bacteria of the Brucella genus. In ruminants, brucellosis causes abortion, followed by chronic infection and secretion of bacteria in milk. In humans, it usually presents as flu-like symptoms, with serious complications if untreated. Epidemiological studies have only recently established that brucellosis can also cause pregnancy complications in women, but the pathogenic mechanisms are unknown. Pioneering studies in ruminants showed that Brucella infect trophoblasts and then colonise the placenta where they grow to high density. A recent study showed that the main zoonotic Brucella species can infect human cytotrophoblasts (CTB) and extravillous trophoblasts (EVT). In this work, we show that Brucella papionis (associated with stillbirth in primates) also infects human trophoblasts. However, it replicates actively in CTB, whereas its replication is very restricted within EVT. We also observed alteration of several trophoblastic functions upon infection by B. papionis or Brucella melitensis (the most prevalent species in human brucellosis). Infection altered the production of hormones, the ability of CTB to form syncytiotrophoblasts, and the invasion capacity of EVT. We also found that infection can spread between different types of trophoblasts. These findings constitute a new step in understanding how Brucella infection causes adverse pregnancy outcomes.


Assuntos
Brucella melitensis/patogenicidade , Brucella/patogenicidade , Brucelose/microbiologia , Trofoblastos/microbiologia , Brucelose/patologia , Feminino , Humanos , Gravidez , Trofoblastos/patologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-27734009

RESUMO

Brucella are highly infectious bacterial pathogens responsible for brucellosis, a frequent worldwide zoonosis. The Brucella genus has recently expanded from 6 to 11 species, all of which were associated with mammals; The natural host range recently expanded to amphibians after some reports of atypical strains from frogs. Here we describe the first in depth phenotypic and genetic characterization of a Brucella strains isolated from a frog. Strain B13-0095 was isolated from a Pac-Man frog (Ceratophyrus ornate) at a veterinary hospital in Texas and was initially misidentified as Ochrobactrum anthropi. We found that B13-0095 belongs to a group of early-diverging brucellae that includes Brucella inopinata strain BO1 and the B. inopinata-like strain BO2, with traits that depart significantly from those of the "classical" Brucella spp. Analysis of B13-0095 genome sequence revealed several specific features that suggest that this isolate represents an intermediate between a soil associated ancestor and the host adapted "classical" species. Like strain BO2, B13-0095 does not possess the genes required to produce the perosamine based LPS found in classical Brucella, but has a set of genes that could encode a rhamnose based O-antigen. Despite this, B13-0095 has a very fast intracellular replication rate in both epithelial cells and macrophages. Finally, another major finding in this study is the bacterial motility observed for strains B13-0095, BO1, and BO2, which is remarkable for this bacterial genus. This study thus highlights several novel characteristics in strains belonging to an emerging group within the Brucella genus. Accurate identification tools for such atypical Brucella isolates and careful evaluation of their zoonotic potential, are urgently required.


Assuntos
Anuros/microbiologia , Brucella/classificação , Brucella/isolamento & purificação , Brucelose/microbiologia , Filogenia , Animais , Proteínas de Bactérias/genética , Sequência de Bases , Evolução Biológica , Brucella/genética , Brucella/metabolismo , Brucelose/mortalidade , Carbono/metabolismo , Linhagem Celular/patologia , Criança , DNA Bacteriano/genética , Células Epiteliais/microbiologia , Feminino , Genes Bacterianos , Genoma Bacteriano , Células HeLa/patologia , Humanos , Lipopolissacarídeos/classificação , Lipopolissacarídeos/genética , Macrófagos/microbiologia , Camundongos , Família Multigênica , Antígenos O/genética , Fenótipo , Ramnose/metabolismo , Texas , Virulência , Zoonoses/microbiologia
5.
Vet Res ; 45: 72, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25029920

RESUMO

Brucella spp. are Gram-negative bacteria that behave as facultative intracellular parasites of a variety of mammals. This genus includes smooth (S) and rough (R) species that carry S and R lipopolysaccharides (LPS), respectively. S-LPS is a virulence factor, and mutants affected in the S-LPS O-polysaccharide (R mutants), core oligosaccharide or both show attenuation. However, B. ovis is naturally R and is virulent in sheep. We studied the role of B. ovis LPS in virulence by mutating the orthologues of wadA, wadB and wadC, three genes known to encode LPS core glycosyltransferases in S brucellae. When mapped with antibodies to outer membrane proteins (Omps) and R-LPS, wadB and wadC mutants displayed defects in LPS structure and outer membrane topology but inactivation of wadA had little or no effect. Consistent with these observations, the wadB and wadC but not the wadA mutants were attenuated in mice. When tested as vaccines, the wadB and wadC mutants protected mice against B. ovis challenge. The results demonstrate that the LPS core is a structure essential for survival in vivo not only of S brucellae but also of a naturally R Brucella pathogenic species, and they confirm our previous hypothesis that the Brucella LPS core is a target for vaccine development. Since vaccine B. melitensis Rev 1 is S and thus interferes in serological testing for S brucellae, wadB mutant represents a candidate vaccine to be evaluated against B. ovis infection of sheep suitable for areas free of B. melitensis.


Assuntos
Proteínas de Bactérias/genética , Vacina contra Brucelose/imunologia , Brucella ovis/imunologia , Brucelose/imunologia , Glicosiltransferases/genética , Lipopolissacarídeos/genética , Doenças dos Ovinos/imunologia , Animais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/metabolismo , Vacina contra Brucelose/genética , Brucelose/microbiologia , Brucelose/veterinária , Feminino , Glicosiltransferases/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Oligossacarídeos/genética , Oligossacarídeos/metabolismo , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Ovinos , Doenças dos Ovinos/microbiologia , Virulência
6.
Microbiology (Reading) ; 158(Pt 8): 2117-2124, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22609756

RESUMO

Haemophilus parasuis is a porcine respiratory pathogen, well known as the aetiological agent of Glässer's disease. H. parasuis comprises strains of different virulence, but the virulence factors of this bacterium are not well defined. A neuraminidase activity has been previously detected in H. parasuis, but the role of sialylation in the virulence of this bacterium has not been studied. To explore the relationship between sialic acid (Neu5Ac) and virulence, we assessed the distribution of genes involved in sialic acid metabolism in 21 H. parasuis strains from different clinical origins (including nasal and systemic isolates). The neuraminidase gene nanH, together with CMP-Neu5Ac synthetase and sialyltransferase genes neuA, siaB and lsgB, were included in the study. Neuraminidase activity was found to be common in H. parasuis isolates, and the nanH gene from 12 isolates was expressed in Escherichia coli and further characterized. Sequence analysis showed that the NanH predicted protein contained the motifs characteristic of the catalytic site of sialidases. While an association between the presence of nanH and the different origins of the strains was not detected, the lsgB gene was predominantly present in the systemic isolates, and was not amplified from any of the nasal isolates tested. Analysis of the lipooligosaccharide (LOS) from reference strains Nagasaki (virulent, lsgB(+)) and SW114 (non-virulent, lsgB(-)) showed the presence of sialic acid in the LOS from the Nagasaki strain, supporting the role of sialylation in the virulence of this bacterial pathogen. Further studies are needed to clarify the role of sialic acid in the pathogenicity of H. parasuis.


Assuntos
Proteínas de Bactérias/genética , Infecções por Haemophilus/veterinária , Haemophilus parasuis/genética , Ácido N-Acetilneuramínico/metabolismo , Doenças dos Suínos/microbiologia , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Infecções por Haemophilus/microbiologia , Haemophilus parasuis/química , Haemophilus parasuis/metabolismo , Haemophilus parasuis/patogenicidade , Dados de Sequência Molecular , Neuraminidase/química , Neuraminidase/genética , Neuraminidase/metabolismo , Alinhamento de Sequência , Suínos , Virulência
8.
Rev. chil. cir ; 41(2): 134-7, jun. 1989. tab
Artigo em Espanhol | LILACS | ID: lil-67791

RESUMO

Se presenta una nueva técnica en el tratamiento de la várices esofágicas sangrantes. Se trata de realizar esofagectomía sin toracotomía con ligadura de la arteria esplénica y ascenso de un tubo gástrico. En los casos previamente esclerosados se realizó un puente esofágico con tubo gástrico, dejando el esófago desfuncionalizado y desvascularizado en el tórax. Se opreraron 7 pacientes: 4 Child C, 2 B y 1 de tipo A. Cinco enfermos se intervinieron en período intrahemorrágico y 2 tenían otras patologías severas agregadas. Se presentaron pocas complicaciones, ningún accidente hemorrágico y no hubo mortalidad operatoria. No hubo hemorragias alejadas. Los pacientes Child C con operación de tipo salvamento fallecen de insuficiencia hepática con sobrevida de 8,3 meses como promedio. De los pacientes resecados sobreviven 2, con menos de 2 años de seguimimiento. Uno fallece de diseminación peritoneal por un cáncer cordial concomitante a los 18 meses y el otro enfermo de una trombosis cerebral a los 3 meses


Assuntos
Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Hemorragia Gastrointestinal , Varizes Esofágicas e Gástricas/cirurgia
9.
Rev. gastroenterol. Perú ; 7(2): 95-101, abr.-jun. 1987. tab, ilus
Artigo em Espanhol | LILACS, LIPECS | ID: lil-57005

RESUMO

Hemos realizado 166 polipectomías endoscópicas rectocolónicas en 159 pacientes (78 varones y 81 mujeres). Noventa polipectomías fueron realizadas mediante asa de alambre y 76 resecciones mediante biopsia térmica y/o reiterativa. El procedimiento fue muy bien tolerado y en esta serie se presentó solamente una hemorragia que fue leve y cedió en forma espontánea. Diecisiete de los pólipos resecados endoscópicamente resultaron ser malignos y sólo en 2 la invasión cancerosa iba más allá de la muscular de la mucosa, lo que representa el 11.7% de las lesiones polipoídeas malignas; lo que demuestra que la mayoría de las lesiones de este tipo (88.3%) encuentra en este procedimiento su tratamiento definitivo. El método de la polipectomía endoscópica se discute en base a la clasificación de Yamada para las lesiones elevadas. En aquellas que son aplanadas y de ancha base de implantación se prefiere la ablación mediante biopsia térmica y/o biopsia reiterativa, mientras en las subpedunculadas y pediculadas la polipectomía con asa de alambre es el método más empleado


Assuntos
Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Humanos , Masculino , Feminino , Endoscopia , Pólipos do Colo/cirurgia
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