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1.
J Endocrinol Invest ; 45(8): 1483-1495, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35181849

RESUMEN

The SARS-CoV-2 virus continues to overwhelm health care systems impairing human to human social and economic interactions. Invasion or damage to the male reproductive system is one of the documented outcomes of viral infection. Existing studies have reported that SARS-CoV-2 may contribute to this loss in relation to inflammatory responses and the formation of cytokine storms in COVID-19 patients. Although direct infection of the testes and entry of SARS-CoV-2 into semen as well as subsequent consequences on the male reproductive system need to be studied more systematically, warnings from two organising ASRM and SART for prospective parents when infected with SARS-CoV-2 should be considered. In the context of an increasingly complex pandemic, this review provides preliminary examples of the potential impact of COVID-19 on male reproductive health and guidance for prospective parents currently infected with or recovering from SARS-CoV-2.


Asunto(s)
COVID-19 , Humanos , Masculino , Pandemias , Estudios Prospectivos , Salud Reproductiva , SARS-CoV-2
2.
Vet Microbiol ; 100(1-2): 91-105, 2004 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-15135517

RESUMEN

Three i-ELISAs using LPS, the immunodominant component of Brucella abortus, were developed with three different conjugates: monoclonal antibodies 1C8 (anti-bovine IgG(1)) and 3H3 (mainly specific for bovine IgG(2) but also reacting with IgG(1)) and protein G (reacts with both bovine IgG subclasses). Using a cut-off value of 2.5U/ml, the i-ELISA with 3H3 as conjugate had a specificity (95% CI: 98.32-99.63%) that was significantly higher than the same assay with 1C8 (95% CI: 96.08-98.26%) or PG (95% CI: 95.83-98.09%). In areas where false positive serological reactions (FPSR) were common, the specificity of the i-ELISAs decreased significantly. The specificity of the i-ELISAs increased with the age of the animals tested, irrespective of the conjugate. The specificity of the i-ELISAs and traditional tests was also examined using sera from animals infected per os with bacteria bearing LPS similar to the Brucella LPS. It appeared that Yersinia enterocolitica O:9, Xanthomonas maltophilia and Salmonella urbana infections induced FPSR both in the i-ELISAs and in the traditional tests, but the 3H3 assay was significantly less prone to produce false positive reactions than the 1C8 and PG assays. The i-ELISAs were more sensitive, allowed earlier detection, and were more persistent than the traditional serological tests both in experimentally and naturally Brucella-infected animals. Weekly i-ELISA monitoring of experimentally infected pregnant heifers (previously vaccinated or not) allowed a prediction of abortion. Furthermore, the 1C8 assay showed significantly higher titres irrespective of day post-infection and vaccination status. The accuracy of the assay could be improved by making use of additional information (e.g. animal age or conjugate) and by selecting appropriate cut-off points on the basis of the prevailing epidemiological situation. The i-ELISAs appear an appropriate choice in order to maintain an official brucellosis-free status because of their sensitivity, early detection and long persistence and, for the same reasons, seem especially valuable for the detection of latent carriers (i.e. animals classified negative by classical serological tests) among imported animals.


Asunto(s)
Anticuerpos Monoclonales/química , Brucella abortus/aislamiento & purificación , Brucelosis Bovina/diagnóstico , Ensayo de Inmunoadsorción Enzimática/veterinaria , Proteínas del Tejido Nervioso/química , Peroxidasa/química , Pruebas de Aglutinación/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Vacuna contra la Brucelosis , Brucelosis Bovina/microbiología , Bovinos , Pruebas de Fijación del Complemento/veterinaria , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática/métodos , Reacciones Falso Positivas , Femenino , Lipopolisacáridos , Embarazo , Sensibilidad y Especificidad , Vacunación/veterinaria
3.
Vet Rec ; 145(8): 214-8, 1999 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-10499853

RESUMEN

Brucellergene OCB (Rhône-Mérieux) was used as an allergen to define the intrinsic parameters of a skin test and to compare its properties with serology for the diagnosis of bovine brucellosis. The skin test was also evaluated for its capacity to solve problems associated with false positive reactions in serological tests. The optimal reading delay for the skin test was 72 hours. The brucellosis allergic reaction was two to three times less intense than the tuberculosis allergic reaction. An increase of 1.1 mm or more in the skin thickness was therefore considered to be an adequate cut-off. The specificity calculated for 1192 brucellosis-free animals (including animals from brucellosis-free herds in which false positive serological reactions had been reported) was 99-83 per cent (95 per cent confidence interval [CI] 99-40 to 99-98 per cent). The sensitivity determined from 27 experimentally infected heifers ranged from 93 per cent (95 per cent CI 76 to 100 per cent) to 78 per cent (95 per cent CI 58 to 91 per cent) when measured respectively one and six months after the infection. Allergic reactions could be detected in vaccinated animals up to four-and-a-half years after the vaccination. On the other hand, no sensitisation was recorded in naïve animals after up to eight monthly injections of the allergen. The skin test gave valuable information, in combination with the serological tests, in both acute and chronic brucellosis. The skin test discriminated brucellosis clearly from false positive serological reactions due to infections with Yersinia enterocolitica O9.


Asunto(s)
Antígenos Bacterianos , Brucella abortus/inmunología , Brucelosis Bovina/diagnóstico , Pruebas Cutáneas/veterinaria , Alérgenos/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Vacuna contra la Brucelosis/inmunología , Brucelosis Bovina/inmunología , Bovinos , Reacciones Cruzadas , Ensayo de Inmunoadsorción Enzimática , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Pruebas Cutáneas/normas
4.
J Med Microbiol ; 46(9): 801-6, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9291893

RESUMEN

Brucellergene is a commercial allergen prepared from Brucella melitensis strain B115 and containing at least 20 cytoplasmic proteins. These proteins were separated by SDS-PAGE. The unstained gel was divided into 18 fractions and proteins were eluted from the gel fractions. The capacity of the separated proteins to elicit delayed-type hypersensitivity (DTH) in infected guinea-pigs or to induce the production of interferon-gamma (IFN-gamma) by blood cells from infected cattle was evaluated. The biological activity of the corresponding protein fractions blotted on to nitrocellulose was measured in a lymphocyte blastogenesis assay. Among the 18 fractions tested, two-spanning the mol. wt ranges 17-22 (fraction 8) and 35-42-kDa (fraction 17)-showed the maximum biological activity in the three tests. These fractions contain two antigens, the Brucella bacterioferritin (BFR) and P39 proteins. Both proteins are good candidates for the detection of cellular immunity to Brucella.


Asunto(s)
Alérgenos/inmunología , Antígenos Bacterianos/inmunología , Proteínas Bacterianas , Brucella melitensis/inmunología , Brucelosis/inmunología , Grupo Citocromo b/inmunología , Ferritinas/inmunología , Linfocitos T/inmunología , Animales , Western Blotting , Brucelosis Bovina/inmunología , Bovinos , Cobayas , Hipersensibilidad Tardía , Interferón gamma/biosíntesis , Activación de Linfocitos
5.
Infect Immun ; 65(2): 495-502, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9009303

RESUMEN

Monoclonal antibodies and polyclonal antisera recognizing a 39-kDa protein (P39) of brucellin, a cytoplasmic extract from Brucella melitensis rough strain B115, were produced. The P39 was purified by anion-exchange chromatography. Eleven of fourteen Brucella-infected cows whose infections had been detected by the delayed-type hypersensitivity (DTH) test with brucellergen also developed a DTH reaction when purified P39 was used as the trigger. The T-cell proliferative responses to P39 of peripheral blood lymphocytes from Brucella-infected cows were also positive. None of the animals infected with other bacterial species that are presumed to induce immunological cross-reactions with Brucella spp. reacted to P39, either in DTH tests or in lymphocyte proliferation assays. A lambda gt11 genomic library of Brucella abortus was screened with a monoclonal antibody specific for P39, and the gene coding for this protein was subsequently isolated. The nucleotide sequence of the P39 gene was determined, and the deduced amino acid sequence is in accordance with the sequence of an internal peptide isolated from P39.


Asunto(s)
Antígenos Bacterianos/genética , Antígenos Bacterianos/aislamiento & purificación , Brucella abortus/química , Brucella abortus/inmunología , Epítopos Inmunodominantes/genética , Epítopos Inmunodominantes/aislamiento & purificación , Alérgenos/administración & dosificación , Alérgenos/química , Secuencia de Aminoácidos , Animales , Antígenos Bacterianos/administración & dosificación , Secuencia de Bases , Brucella abortus/genética , Bovinos , Cromatografía por Intercambio Iónico , Clonación Molecular , Reacciones Cruzadas , Citoplasma/inmunología , Femenino , Genes Bacterianos , Hibridomas/química , Hibridomas/inmunología , Hipersensibilidad Tardía/etiología , Epítopos Inmunodominantes/administración & dosificación , Activación de Linfocitos , Datos de Secuencia Molecular , Peso Molecular
6.
Cancer Lett ; 60(1): 25-32, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1913624

RESUMEN

The free radical scavengers N-acyl dehydroalanines (AD compounds) were examined for their effect on several 12-O-tetradecanoylphorbol-13-acetate (TPA) elicited events in mouse skin. The induction of oxidant production by TPA in isolated mouse epidermal cells was reduced by approximately 70% by 1 mM paramethoxyphenyl-acetyl dehydroalanine (AD5) and 80% by 1 mM parasulfoxyphenyl-acetyl dehydroalanine (AD19). These AD compounds also completely suppressed the TPA-dependent stimulation of prostaglandin E2 synthesis in primary cultures of epidermal cells. Single and multiple topical applications on the dorsal skin of SENCAR mice of either AD5 or AD 19 inhibited TPA-induced epidermal hyperplasia but failed to inhibit epidermal ornithine decarboxylase induction. When used with TPA on initiated mice, AD19 did not inhibit papilloma formation; however, after 40 weeks of promotion, the carcinoma incidence was reduced by 50% in the AD19 group. These results suggest that reactive oxygens may be more important to the conversion of benign to malignant tumors than in the initial development of the benign tumors.


Asunto(s)
Alanina/análogos & derivados , Depuradores de Radicales Libres , Neoplasias Cutáneas/metabolismo , Piel/efectos de los fármacos , Acetato de Tetradecanoilforbol/farmacología , Alanina/farmacología , Animales , Células Cultivadas , Dinoprostona/biosíntesis , Femenino , Hiperplasia/inducido químicamente , Hiperplasia/metabolismo , Hiperplasia/prevención & control , Mediciones Luminiscentes , Ratones , Ornitina Descarboxilasa/metabolismo , Oxígeno/metabolismo , Piel/enzimología , Piel/patología , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/prevención & control
7.
Carcinogenesis ; 9(11): 2009-13, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3180339

RESUMEN

To better understand the role of free radicals in liver carcinogenesis, endogenous antioxidant defense systems and the susceptibility of membranes to lipid peroxidation were evaluated in early lesions and in malignant tumors induced by the Solt-Farber resistant hepatocyte protocol. These parameters were also measured in the liver surrounding these tumors. In comparison with the normal liver, both nodules and carcinomas show a different biochemical pattern consisting of decreased glutathione peroxidase (GSH peroxidase) and catalase activities plus increased glutathione reductase (GSSG reductase) activity. In contrast, 1 week after the application of the initiation-selection protocol, the liver displays a high level of glutathione (GSH), high GSSG reductase activity, a reduced production of malondialdehyde and no changes in superoxide dismutase and GSH peroxidase activities. These data suggest that the liver is well protected against reactive oxygen species. During the carcinogenic process, the liver parenchyma surrounding the altered foci recovers from most of the modifications induced by the initiation-selection treatment. These results add additional support for the hypothesis that the appearance of early alterations in the liver, after a carcinogenic treatment, might be an adaptive response to a hazardous environment in which selected cell populations are transformed into nodules and/or carcinomas.


Asunto(s)
Peróxidos Lipídicos/metabolismo , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Oxígeno/metabolismo , Animales , Catalasa/metabolismo , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Mediciones Luminiscentes , Masculino , Oxidación-Reducción , Lesiones Precancerosas/metabolismo , Ratas , Superóxido Dismutasa/metabolismo
8.
Chem Biol Interact ; 47(2): 175-94, 1983 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6418395

RESUMEN

To evaluate the predictive value of serum antipyrine half-life AP(T1/2) as an index of hepatic carcinogen metabolism, groups of C57BL/6 and DBA/2 mice were treated with various inducers and inhibitors of cytochrome P-450-dependent monooxygenases (pregnenolone-16 alpha-carbonitrile (PCN), phenobarbital (PB), 5,6-benzoflavone (5,6-BF), 3-methylcholanthrene (MC), disulfiram (DIS), 7,8-BF). Groups of mice were also given ethanol (3% in drinking water) for 12 days. Within each group, mean serum AP-(T1/2) was compared with (i) the in vitro activity of hepatic microsomal benzo[alpha]pyrene (BP) 3-hydroxylase, 2-acetylaminofluorene (AAF)-N-hydroxylase and aldrin monooxygenase, and (ii) the liver S9-mediated mutagenicity of aflatoxin B1 (AFB), trans-7,8-dihydro-7,8-dihydroxybenzo[alpha]pyrene (BP 7,8-diol), 2-acetylaminofluorene and N-nitrosomorpholine (NMOR) in Salmonella typhimurium strains. Serum AP(T1/2) was only correlated negatively with the activity of BP 3-hydroxylase (P less than 0.001) and aldrin monooxygenase (P less than 0.001). No statistically significant correlation was found between serum AP(T1/2) and liver S9-mediated mutagenicity for any of the four carcinogens. On the basis of these results, we conclude that serum AP(T1/2) may not be a reliable index of the capacity of liver to convert carcinogens into reactive intermediates.


Asunto(s)
Antipirina/sangre , Dihidroxidihidrobenzopirenos , Hígado/enzimología , Mutágenos , Oxigenasas/metabolismo , 2-Acetilaminofluoreno/farmacología , Aflatoxina B1 , Aflatoxinas/farmacología , Animales , Benzopirenos/farmacología , Sistema Enzimático del Citocromo P-450 , Femenino , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Mutágenos/farmacología , Nitrosaminas/farmacología
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