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1.
Front Endocrinol (Lausanne) ; 12: 745984, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34630335

RESUMO

Although spermatogenic dysfunction is widely found in patients with human immunodeficiency virus (HIV), the underlying reasons remain unclear. Thus far, potential hypotheses involving viral reservoirs, testicular inflammation, hormone imbalance, and cachexia show inconsistent correlation with spermatogenic dysfunction. Here, northern pig-tailed macaques (NPMs) exhibited marked spermatogenic dysfunction after long-term infection with simian immunodeficiency virus (SIVmac239), with significant decreases in Johnsen scores, differentiated spermatogonial stem cells, and testicular proliferating cells. The above hypotheses were also evaluated. Results showed no differences between SIV- and SIV+ NPMs, except for an increase in follicle stimulating hormone (FSH) during SIV infection, which had no direct effect on the testes. However, long-term SIVmac239 infection undermined pancreatic islet ß cell function, partly represented by significant reductions in cellular counts and autophagy levels. Pancreatic islet ß cell dysfunction led to glucose metabolism disorder at the whole-body level, which inhibited lactate production by Sertoli cells in testicular tissue. As lactate is the main energy substrate for developing germ cells, its decrease was strongly correlated with spermatogenic dysfunction. Therefore, glucose metabolism disorder appears to be a primary cause of spermatogenic dysfunction in NPMs with long-term SIVmac239 infection.


Assuntos
Transtornos do Metabolismo de Glucose/complicações , Macaca nemestrina , Síndrome de Imunodeficiência Adquirida dos Símios/complicações , Espermatogênese/fisiologia , Animais , Glucose/metabolismo , Transtornos do Metabolismo de Glucose/fisiopatologia , Transtornos do Metabolismo de Glucose/veterinária , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Infertilidade Masculina/fisiopatologia , Infertilidade Masculina/veterinária , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Células Secretoras de Insulina/virologia , Macaca nemestrina/metabolismo , Macaca nemestrina/fisiologia , Macaca nemestrina/virologia , Masculino , Análise do Sêmen/veterinária , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/fisiopatologia , Vírus da Imunodeficiência Símia/fisiologia
2.
J Dairy Sci ; 97(12): 7538-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25282414

RESUMO

The objective of this study was to evaluate the suitability of the electronic handheld devices FreeStyle Precision (FSP; Abbott Germany, Wiesbaden, Germany) and GlucoMen LX Plus (GML; A. Menarini GmbH, Vienna, Austria) for the measurement of ß-hydroxybutyrate (BHBA) in whole blood in dairy goats. Additionally, glucose concentration was analyzed with the FSP device. For method comparison, the samples were also analyzed in the laboratory by standard methods, which served as the gold standard in our study. A further objective was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole blood samples from the jugular vein (vena jugularis). In total, 173 blood sample pairs collected from 28 goats were obtained from an ear vein and from the jugular vein. The Spearman correlation coefficients (rsp) for BHBA concentrations determined with the FSP or GML and the gold standard were 0.95 and 0.85 for the ear vein and 0.98 and 0.88 for the jugular vein, respectively. Bland-Altman plots of differences showed a positive bias of 0.12 (ear vein) and 0.21 (jugular vein) when determination was performed with the FSP and a negative bias of 0.21 (ear vein) and 0.24 (jugular vein) when using the GML. For the FSP, applying the adjusted thresholds determined by ROC analysis of 0.9 (ear vein) and 1.0 mmol/L (jugular vein) allowed to distinguish between healthy goats and animals with hyperketonemia with sensitivities (Se) and specificities (Sp) for samples from the ear vein of 0.98 and 0.85, and from the jugular vein of 0.99 and 0.94, respectively. For the GML, adjusted thresholds were 0.5 mmol/L for the ear vein (Se=0.94, Sp=0.75) and 0.6 mmol/L for the jugular vein (Se=0.88, Sp=0.91). Repeated analyses of defined whole blood samples showed average inter- and intraassay coefficients of variation of 6.6 and 7.3% for FSP, and of 35.6 and 35.4% for GML, respectively. Test characteristics for determining glucose concentration with the FSP compared with the gold standard were poor (ear vein: rsp=0.41; jugular vein: rsp=0.51), with low validity to distinguish between hypo- and normoglycemia (Se=0.71, Sp=0.66). The present study showed good test characteristics for the FSP and moderate for the GML device for determining BHBA concentrations in whole blood. Additionally the results demonstrate the suitability of testing BHBA concentration in a blood drop obtained from an ear vein. Based on the results of this study, the FSP device is not suitable to differentiate normo- from hypoglycemia in goats.


Assuntos
Ácido 3-Hidroxibutírico/sangue , Glicemia/análise , Computadores de Mão/normas , Transtornos do Metabolismo de Glucose/veterinária , Doenças das Cabras/diagnóstico , Cetose/veterinária , Animais , Feminino , Transtornos do Metabolismo de Glucose/diagnóstico , Transtornos do Metabolismo de Glucose/fisiopatologia , Doenças das Cabras/fisiopatologia , Cabras , Cetose/diagnóstico , Cetose/fisiopatologia , Curva ROC , Sensibilidade e Especificidade
3.
Arq. bras. med. vet. zootec ; 64(5): 1127-1132, out. 2012. ilus
Artigo em Português | LILACS | ID: lil-655881

RESUMO

Compararam-se as concentrações de cálcio, glicose e insulina em ovelhas gestantes e não gestantes submetidas ao teste de tolerância à glicose (TTG). Oito ovelhas gestantes (GG) e oito não gestantes (NG) foram submetidas ao TTG por meio da administração endovenosa de uma solução de glicose, na dose de 500mg/kg de peso vivo. Amostras de sangue foram coletadas nos tempos de -15, zero, 15, 30, 45, 60, 90, 120, 150 e 180 minutos, sendo zero min o momento da infusão, para avaliação da concentração sanguínea de glicose, cálcio e insulina. Foi avaliada a taxa de metabolização de glicose e insulina, por meio do cálculo da área sob a curva (ASC). As concentrações de glicose, cálcio, insulina e a ASC da insulina não diferiram entre os grupos (P>0,05), entretanto as três últimas ASCs da glicose foram mais elevados nas gestantes (P<0,05), que correspondem ao período entre 90 e 180min. O teste de correlação de Pearson revelou correlação negativa entre concentração de cálcio e insulina nas gestantes (P<0,05). Estes resultados indicam menor taxa de metabolização de glicose em ovelhas gestantes e uma possível relação de cálcio e insulina no terço final de gestação.


The aim of this study was to investigate glucose, insulin and calcium metabolism during the Glucose Tolerance Test (GTT) in pregnant or nonpregnant ewes. Eight pregnant (PG) and nonpregnant (NPG) ewes per group received a glucose endovenosus bolus containning 500mg/kg in one minute. Blood samples were collected on -15, 0, 15, 30, 45, 60, 90, 120, 150 and 180 minutes interval (0 min - injection). These samples were used to evaluate glucose, calcium, insulin concentration, as well as insulin and glucose metabolization rate, which were determined by calculating the Area Under the Curve (AUC). The calcium, glucose and insulin concentrations were not different between groups. However, the three last glucose ASCs were higher in the pregnant group and in this group calcium and insulin blood concentrations were negatively correlated .These results showed lower glucose tolerance in pregnant ewes and suggest a link between insulin and calcium in the late pregnancy.


Assuntos
Animais , Ovinos/metabolismo , Transtornos do Metabolismo de Glucose/veterinária , Cálcio/análise , Insulina/análise , Teste de Tolerância a Glucose/veterinária
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