Dimethyl acetamide and dimethyl sulfoxide associated at glucose and egg yolk for cryopreservation of Pseudoplatystoma corruscans semen

This study aimed to develop a protocol for the cryopreservation of Pseudoplatystoma corruscans semen. For this, mature males were hormonally induced with a single dose of carp pituitary extract (5 mg/kg body weight). Semen was collected and evaluated. Two cryoprotectants were tested to compose the diluents: dimethyl acetamide (DMA) and dimethyl sulfoxide (Me2SO), in two concentrations (8% and 10%), + 5.0% glucose + 10% egg yolk. The semen was diluted in a 1: 4 ratio (semen: extender), packed in 0.5 mL straws and frozen in a dry shipper container in liquid nitrogen vapors. After thawing, sperm kinetics, sperm morphology and DNA integrity of cryopreserved sperm were evaluated. Pseudoplatystoma corruscans males produced semen with sperm motility > 80%. After thawing, all treatments provided semen with total sperm motility > 40%, with no significant difference (P < 0.05) between them, as well as between the other sperm kinetic parameters evaluated. The treatments with DMA provided a smaller fragmentation of the DNA of the gametes. Sperm malformations were identified in both fresh and cryopreserved semen, with a slight increase in these malformations being identified in sperm from thawed P. corruscans semen samples.(AU)

Este estudo teve como objetivo desenvolver um protocolo para a criopreservação do sêmen de Pseudoplatystoma corruscans. Para tal, machos maduros foram induzidos hormonalmente com uma dose única de extrato de hipófise de carpa (5 mg/kg de peso vivo). O sêmen foi coletado e avaliado. Sendo testados para compor os diluentes, dois crioprotetores: dimetil acetamida (DMA) e dimetil sulfóxido (Me2SO), em duas concentrações (8% e 10%), + 5,0% glicose + 10% gema de ovo. O sêmen foi diluído na proporção 1: 4 (sêmen: extensor), embalado em palhetas de 0,5 mL e congelado em container dryshipper em vapores de nitrogênio líquido. Após o descongelamento, foram avaliados os aspectos cinéticos espermáticos, a morfologia espermática e a integridade do DNA dos espermatozoides criopreservados. Os machos de P. corruscans produziram sêmen com motilidade espermática > 80%. Todos os tratamentos proporcionaram após o descongelamento sêmen com motilidade espermática total > 40%, sem diferença significativa (P < 0,05) entre eles, como também entre os demais parâmetros cinéticos espermáticos avaliados. Os tratamentos com DMA proporcionaram uma menor fragmentação do DNA dos gametas. Malformações espermáticas foram identificadas, tanto no sêmen fresco, como no criopreservado, sendo identificado um aumento discreto dessas malformações nos espermatozoides das amostras de sêmen descongeladas de P. corruscans.(AU)

Linezolid.

Linezolid is an oxazolidinone antibacterial agent that acts by inhibiting the initiation of bacterial protein synthesis. Linezolid has a wide spectrum of activity against gram-positive organisms including methicillin resistant staphylococci, penicillin resistant pneumococci and vancomycin resistant enterococcus faecalis and E. faecium. Linezolid has a good bio-availability orally and could be switched from parenteral to oral therapy while treating serious infections. Linezolid is well tolerated in children.

Glucose-6-phosphatase Activity and Ultrastructures in Hepatocytes of Thioacetamide-treated Mice

To investigate the earlier cellular alterations(Glucose-6-Pase activity and morphologic features) caused by a hepatotoxin, thioacetamide (TAA), a single dose of the agent (200mg per kg of body weight) was given intraperitoneally to mice, which were sacrificed at intervals of 4, 8 or 16 hours after corresponding treatments. For histochemical study of glucose-6-phosphatase (G6Pase) activity, unfixed frozen sections were incubation of the Wachstein and Meisel medium and stained. The smallest pieces of liver tissue were fixed in glutaraldehyde and osmic acid, and stained by the routine electron-microscopic techniques. Some pieces of liver were fixed in 10% formalin, embedded in paraffin, and stained with hematoxylin and eosin. There was a rapid and progressive loss of G6Pase activity, in an orderly time sequence, in the experimental group. There were also morphologic changes: loss of cytoplasmic basophilia, cell infiltration and necrosis in the centrilobular and intermediate zones, and an increase of sER, small vesicles and ribosomes in the cytoplasm of hepatocytes, the marked changes of nuclei and nucleoli, and a slight increase of lipid droplets in the cytoplasm at 16 hours after intoxication. The correlation between these cellular alterations was discussed in view of mechanisms in the hepatotoxic action.

Glucose-6-phosphatase Activity and Ultrastructures in Hepatocytes of Thioacetamide-treated Mice

To investigate the earlier cellular alterations(Glucose-6-Pase activity and morphologic features) caused by a hepatotoxin, thioacetamide (TAA), a single dose of the agent (200mg per kg of body weight) was given intraperitoneally to mice, which were sacrificed at intervals of 4, 8 or 16 hours after corresponding treatments. For histochemical study of glucose-6-phosphatase (G6Pase) activity, unfixed frozen sections were incubation of the Wachstein and Meisel medium and stained. The smallest pieces of liver tissue were fixed in glutaraldehyde and osmic acid, and stained by the routine electron-microscopic techniques. Some pieces of liver were fixed in 10% formalin, embedded in paraffin, and stained with hematoxylin and eosin. There was a rapid and progressive loss of G6Pase activity, in an orderly time sequence, in the experimental group. There were also morphologic changes: loss of cytoplasmic basophilia, cell infiltration and necrosis in the centrilobular and intermediate zones, and an increase of sER, small vesicles and ribosomes in the cytoplasm of hepatocytes, the marked changes of nuclei and nucleoli, and a slight increase of lipid droplets in the cytoplasm at 16 hours after intoxication. The correlation between these cellular alterations was discussed in view of mechanisms in the hepatotoxic action.