Efeito da inibição da óxido nítrico sintase induzível na capacitação in vitro de espermatozoides bovinos Effect of inhibition of inducible nitric oxide synthase on in vitro capacitation of bovine spermatozoa

Avaliaram-se o papel do óxido nítrico (NO) por meio da inibição da enzima óxido nítrico sintase induzível (iNOS), após a adição da aminoguanidina (AG), na motilidade, no vigor e na integridade da membrana plasmática nos tempos de 15, 60, 120, 180, 240 e 300min e a atividade mitocondrial e a capacitação de espermatozoides bovinos após 300min de cultivo. Adicionaram-se diferentes concentrações (0,001, 0,01 e 0,1M) de AG durante a capacitação induzida pela heparina e 500&#956;M de nitroprussiato de sódio (SNP, doador de NO) à concentração deletéria. A adição de 0,1M de AG diminuiu a motilidade e o vigor espermático e a integridade da membrana (P<0,05). A adição de SNP ao meio de cultivo com 0,1M de AG somente reverteu a integridade da membrana após 300min. A inibição da síntese de NO pela adição de AG não alterou a atividade mitocondrial. A percentagem de oócitos penetrados com espermatozoides tratados com 0,01 e 0,1M de AG diminuiu 20,3 e 100%, respectivamente, em relação aos não tratados (controle) (P<0,05), contudo houve aumento de 15% na percentagem de oócitos desnudados penetrados com espermatozoides capacitados em presença de 0,1M de AG. Conclui-se que a inibição da síntese de NO pela AG diminuiu a qualidade espermática durante a capacitação de espermatozoides bovinos in vitro, exceto a atividade mitocondrial. Somente a integridade da membrana foi revertida após adição de NO, sugerindo diferentes vias de ação do NO na qualidade espermática ao longo da capacitação in vitro de espermatozoides bovinos.<br>The role of nitric oxide (NO) was evaluated by inhibition of inducible nitric oxide synthase (iNOS), with aminoguanidine (AG) on motility, vigor, and plasmatic membrane integrity of bovine spermatozoa culture after 15, 60, 120, 180, 240, and 300min and on mitochondrial activity and capacitation after 300min, respectively. Different concentrations, 0.001, 0.01, and 0.1M of AG were added during the heparin induced capacitation and sodium nitroprusside (SNP, NO donor-500&#956;M) to the deleterious concentration. The addition of 0.1M of AG diminished progressive motility, spermatic vigor, and membrane integrity (P<0.05). SNP addition to the 0.1M of AG did revert only plasmatic membrane integrity after 300min. Mitochondrial activity was not influenced by addition of AG. Percentage of penetrated oocytes after addition of 0.01 and 0.1M of AG diminished, 20.3 and 100%, respectively, in relation to the control oocytes (P<0.05). However, an increase of 15% was observed when denuded oocytes were used with 0.1M AG treated sperm (P<0.05). It was concluded that the inhibition of NO synthesis with aminoguanidine diminished sperm quality during in vitro capacitation of bovine spermatozoa, except the mitochondrial activity. Only membrane integrity was reverted with the addition of NO to culture medium, suggesting different pathways of NO action on bovine sperm quality during in vitro capacitation

5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: protocol, methods, and analysis of data.

BACKGROUND: Accidental awareness during general anaesthesia (AAGA) with recall is a potentially distressing complication of general anaesthesia that can lead to psychological harm. The 5th National Audit Project (NAP5) was designed to investigate the reported incidence, predisposing factors, causality, and impact of accidental awareness. METHODS: A nationwide network of local co-ordinators across all the UK and Irish public hospitals reported all new patient reports of accidental awareness to a central database, using a system of monthly anonymized reporting over a calendar year. The database collected the details of the reported event, anaesthetic and surgical technique, and any sequelae. These reports were categorized into main types by a multidisciplinary panel, using a formalized process of analysis. RESULTS: The main categories of accidental awareness were: certain or probable; possible; during sedation; on or from the intensive care unit; could not be determined; unlikely; drug errors; and statement only. The degree of evidence to support the categorization was also defined for each report. Patient experience and sequelae were categorized using current tools or modifications of such. CONCLUSIONS: The NAP5 methodology may be used to assess new reports of AAGA in a standardized manner, especially for the development of an ongoing database of case reporting. This paper is a shortened version describing the protocols, methods, and data analysis from NAP5--the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home

Semi-peripheries or Particular Pathways: the case of Australia, New Zealand and Canada as class formations

The paper deals comparatively with the class structures of Australia, New Zealand and Canada. Four hypotheses, which could account for the similarities and differences in class structure, are identified. The first is based on their semi-peripheral status in the world economy; the second, pertaining particularly to Canada, argues for an ‘Americanisation effect’; the third is based on their similar heritage in the context of dominion capitalism; while the fourth proposes purely endogenous determination. The differences in class structure that the analysis reveals, particularly with respect to the managerial class, can perhaps be more persuasively explained in terms of the different historical circumstances of the three countries rather than by a set of exogenous factors which impact on all of them