OBJECTIVE Exposure to normobaric hyperoxia protects the heart against ischemia-reperfusion injury ex vivo. In the present study, we investigated the effect of the early and late phase of hyperoxia on in vivo myocardial infarction and apoptosis. METHODS Rats were exposed to room air preoxygenation (O(2)≥ 95%) followed by regional ischemia (30 min) and 0, 90, 180, and 360 min of reperfusion. Hy...

PURPOSE To determine whether the p53 protein plays a role in the selective vulnerability of the inner retina to transient ischemia. METHODS Transient retinal ischemia was induced using a high intraocular pressure (HIOP) model in the Sprague-Dawley rat for 60 minutes. Histopathologic outcome was determined 7 days after ischemia. In addition, analysis for evidence for apoptosis (TdT-dUTP termin...

BACKGROUND AND PURPOSE To clarify the relationship between apurinic/apyrimidinic endonuclease (APE/Ref-1), a multifunctional protein in the DNA base excision repair pathway, and delayed neuronal cell death associated with apoptosis, we examined the expression of APE/Ref-1 before and after transient global ischemia in rats. METHODS Global ischemia was induced by bilateral common carotid artery...

s:1993:"Background: There are many approaches that gene expression is controlled in eukaryotes. DNA methylation is one of several epigenetic mechanisms that cells use to control gene expression and lock genes in the "off" position. In addition, sperm DNA damage can correlate with DNA methylation defect. There is evidence that sperm of infertile men contain more DNA damage than fertile men and t...

BACKGROUND AND PURPOSE DNA damage and the DNA repair mechanism are known to be involved in ischemia/reperfusion injury in the brain. The x-ray repair cross-complementing group 1 (XRCC1) protein plays a central role in the DNA base excision repair pathway by interacting with DNA ligase III and DNA polymerase beta. The present study examined the protein expression of XRCC1 and DNA fragmentation b...

BACKGROUND Vascular endothelial growth factor (VEGF), a substance that stimulates new blood vessel formation, is an important survival factor for endothelial cells. Although overexpressed VEGF in the lung induces pulmonary edema with increased lung vascular permeability, the role of VEGF in the development of acute lung injury remains to be determined. METHODS To evaluate the role of VEGF in ...

Oxidant stress is critically involved in various liver diseases. Superoxide formation causes c-Jun NH2-terminal kinase (JNK)- and caspase-dependent apoptosis in cultured hepatocytes. To verify these findings in vivo, male Fisher rats were treated with diquat and menadione. The oxidant stress induced by both compounds was confirmed by increased formation of glutathione disulfide and 4-hydroxynon...

PURPOSE To develop and characterize a mouse model of elevated intraocular pressure (IOP) as a means to investigate the underlying cellular and genetic mechanisms of glaucomatous optic neuropathy. METHODS An experimental increase in IOP was induced in one eye of each adult C57BL/6J mouse by argon laser photocoagulation of the episcleral and limbal veins. The IOP of both eyes of each mouse was ...

objective: this study aimed to evaluate the incidence of apoptosis in vitrified and non-vitrified human ovarian tissue by the use of morphological analysis and apoptosis assay techniques. methods: we obtained human ovarian tissue biopsies from 30 women who underwent elective caesarean sections. tissues were transported to the laboratory in pre-warmed, equilibrated leibovitz l-15 medium within 2...

The purpose of this investigation was to determine the effects of sevoflurane on rats with ischemic brain injury and to determine the potential role of the TREK-1 channel in this process. Normal rats were randomly divided into three groups: Sham operation, sevoflurane anesthesia or chloral hydrate anesthesia group, an additional group of TREK-1 knockout rats were also studied. Semi-quantitative...