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1.
Anim Biotechnol ; 30(1): 21-29, 2019 Jan.
Article in English | MEDLINE | ID: mdl-29382256

ABSTRACT

This study aimed to detect the most deleterious ROS for goat sperm and then supplemented the extender with a proper antioxidant. For this, 12 adult goats (aged 1-7) were used. Fresh samples were submitted to challenge with different ROS (superoxide anion, hydrogen peroxide, and hydroxyl radical) and malondialdehyde (MDA-toxic product of lipid peroxidation). After experiment 1, sperms were cryopreserved in extenders supplemented to glutathione peroxidase (Control: 0 UI/mL; GPx1: 1 UI/mL; GPx5: 5 UI/mL, and GPx10: 10 UI/mL) and catalase (Control: 0 UI/mL; CAT60: 60 UI/mL; CAT120: 120 UI/mL, and CAT240: 240 UI/mL). Each sample was evaluated by motility, plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, assay of the sperm chromatin structure, mitochondrial activity (3,3-diaminobenzidine), and measurement of lipid peroxidation (thiobarbituric acid reactive substances [TBARS]). It was possible to observe a mitochondrial dysfunction (DAB-Class IV) and low membrane integrity after hydrogen peroxide action. However, the high rates of TBARS were observed on hydroxyl radical. CAT240 presents the lower percentage of plasma membrane integrity. It was possible to attest that hydrogen peroxide and hydroxyl radical are the more harmful for goat sperm. Antioxidant therapy must be improving perhaps using combination between antioxidants.


Subject(s)
Antioxidants/pharmacology , Catalase/pharmacology , Cryopreservation/veterinary , Glutathione Peroxidase/pharmacology , Goats/physiology , Spermatozoa/drug effects , Acrosome/drug effects , Animals , Cell Membrane/drug effects , Chromatin/drug effects , Cryopreservation/methods , Goats/genetics , Lipid Peroxidation/drug effects , Male , Oxidative Stress/drug effects , Reactive Oxygen Species/adverse effects , Spermatozoa/physiology
2.
Reprod Domest Anim ; 52(2): 289-297, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28058736

ABSTRACT

Studies have demonstrated the importance of mitochondria to sperm functionality, as the main source of ATP for cellular homoeostasis and motility. However, the role of mitochondria on sperm metabolism is still controversial. Studies indicate that, for some species, glycolysis may be the main mechanism for sperm energy production. For ram sperm, such pathway is not clear. Thus, we evaluated ram sperm in response to mitochondrial uncoupling and glycolysis inhibition aiming to assess the importance of each pathway for sperm functionality. Statistical analysis was performed by the SAS System for Windows, using the General Linear Model Procedure. Data were tested for residue normality and variance homogeneity. A p < .05 was considered significant. Groups treated with the mitochondrial uncoupler Carbonyl cyanide 3 chlorophenylhydrazone (CCCP) showed a decrease in the percentage of cells with low mitochondrial activity and high mitochondrial membrane potential. We also observed that the highest CCCP concentration promotes a decrease in sperm susceptibility to lipid peroxidation. Regardless the lack of effect of CCCP on total motility, this substance induced significant alterations on sperm kinetics. Besides the interference of CCCP on spermatic movement patterns, it was also possible to observe such an effect in samples treated with the inhibitor of glycolysis (2-deoxy-d-glucose, DOG). Furthermore, treatment with DOG also led to a dose-dependent increase in sperm susceptibility to lipid peroxidation. Based on our results, we suggest that the glycolysis appears to be as important as oxidative phosphorylation for ovine sperm kinetics as this mechanism is capable of maintaining full motility when most of the cells have a low mitochondrial membrane potential. Furthermore, we found that changes in the glycolytic pathway trough glycolysis inhibition are likely involved in mitochondrial dysfunction and sperm oxidative unbalance.


Subject(s)
Mitochondria/physiology , Sheep/physiology , Spermatozoa/physiology , Animals , Carbonyl Cyanide m-Chlorophenyl Hydrazone/analogs & derivatives , Glycolysis , Humans , Male , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/physiology , Oxidative Stress , Spermatozoa/drug effects
3.
Andrology ; 2(6): 955-66, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25270366

ABSTRACT

The use of clonidine, a selective agonist of α2-adrenoceptors, is related to the fertility impairment. Thus, it has been described that changes in the epididymal function are related to the loss of fertility. Therefore, this study was sought to further evaluate the effects of clonidine in the rat distal cauda epididymis contractions and its consequence in the sperm parameters. The in vitro effects of clonidine in the isolated distal cauda epididymis were evaluated by pharmacological experiments. The consecutive contractile responses for clonidine in distal cauda epididymis showed desensitization. The noradrenaline-induced contractions were desensitized after in vitro clonidine pre-treatment (10(-5) M for 10 min). Clonidine was unable to alter the noradrenaline contractions if the in vitro pre-treatment was made in the presence of idazoxan (α2-adrenoceptor antagonist), whereas prazosin (α1-adrenoceptor antagonist) was ineffective. Moreover, the in vitro clonidine pre-treatment increased frequency and amplitude of spontaneous contraction of distal cauda epididymis. In addition, to induce in vivo desensitization of α2-adrenoceptors, male Wistar rats were treated with crescent doses of clonidine and distal cauda of epididymis contraction and sperm parameters were analyzed. The in vivo treatment with clonidine diminished the potency of the contractions induced by adrenergic agonists and augmented the frequency and amplitude of spontaneous contraction of distal cauda epididymis. This treatment also altered the sperm transit time in epididymis, epididymal sperm reserves, sperm lipid peroxidation, and antioxidant enzymes activity. The results suggest that clonidine was able to affect the sperm quantity and quality by decreasing the transit time related to the increase in the frequency and amplitude of spontaneous contractions in epididymis, although the contractions induced by adrenergic agonists were desensitized.


Subject(s)
Adrenergic alpha-2 Receptor Agonists/pharmacology , Clonidine/pharmacology , Epididymis/drug effects , Spermatozoa/drug effects , Animals , Epididymis/physiology , Male , Muscle Contraction/drug effects , Rats , Rats, Wistar
4.
Rev. chil. infectol ; 18(supl.2): 66-76, 2001.
Article in Spanish | LILACS | ID: lil-313255

ABSTRACT

Ventilator-associated pneumonia is a life-threatening disease causing an increased morbidity, cost and length of stay in the intensive care unit. This document is an evidence based consensus which discusses preventive measures including medical recommendations and practices for cleaning and handling mechanical ventilators. Standard and contact precautions are critical preventive measures


Subject(s)
Humans , Pneumonia/prevention & control , Respiration, Artificial/adverse effects , Antibiotic Prophylaxis , Sterilization/methods , Gastrointestinal Hemorrhage , Intubation, Intratracheal/methods , Pneumonia/etiology , Risk Factors
6.
Rev. chil. infectol ; 14(1): 55-6, 1997.
Article in Spanish | LILACS | ID: lil-211978

ABSTRACT

Se comunica caso de lactante que adquirió meningitis neumocóccica causada por una cepa medianamente sensible a penicilina-CIM 1 µg/ml y resistente a ceftriaxona- CIM 3 µg/ml. El tratamiento inicial incluyó ceftriaxona 100 mg/kg/día y dexametasona. Hubo una esterilización tardía del LCR y graves secuelas neurológicas al egreso pese al tratamiento con vancomicina sistémica e intraventricular. Este es el primer caso documentado de resistencia a cefalosporinas de tercera generación, relacionado a fracaso terapéutico en meningitis, en nuestro hospital


Subject(s)
Humans , Male , Infant , Meningitis, Pneumococcal/drug therapy , Streptococcus pneumoniae/drug effects , Meningitis, Pneumococcal/complications , Penicillin Resistance , Vancomycin/therapeutic use
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