Biomedical subjects

F He

Publications and source records attributed to F He.

149 records · Page 9Linked to original sources

PubMedDate not supplied

Association between metabolic gene polymorphisms and susceptibility to peripheral nerve damage in workers exposed to n-hexane: a preliminary study.

Chronic exposure to n-hexane may result in peripheral neuropathy. 2,5-Hexanedione (2,5-HD) has been identified as a toxic metabolite of n-hexane. The CYP2E1, CYP1A1 and GST genes are involved in the formation of 2,5-hexanedione from n-hexane as well as the elimination of 2,5-HD-formed electrophile, and these genes are highly polymorphic in the general population. A nested case-control study in an industrial cohort was conducted to evaluate the associations between polymorphisms in these metabolic genes and n-hexane-induced peripheral nerve damage. The study subjects included 22 cases, who worked in a printing factory with symptoms of peripheral nerve damage, and 163 controls, who came from the same factory of cases. DNA was extracted from blood samples and genotyping was conducted for CYP2E1 Pst, CYP2E1 Dra, CYP2E1 Ins96, CYP1A1 Msp, GSTT1 null, GSTM1 null and GSTP1 105V. Unconditional logistic regression was applied to estimate the odds ratio and 95% confidence intervals. There were no significant differences between the two groups regarding age, sex, smoking and alcohol status. A significant association between Dra polymorphism and peripheral nerve damage was found. The frequency of CYP2E1 Dra homozygous mutation in the case group (18.2%) was higher than that in the control group (3.7%, p=0.015). Individuals with homozygote genotype (CC) of CYP2E1 Dra had a significantly higher risk of peripheral nerve damage compared with those with DD genotype (adjusted OR=?.58, 95% CI=1.32-23.65) after n-hexane exposure duration, sex, age, smoking and alcohol status were adjusted. No significant association was found that CYP2E1 Pst, CYP2E1 Ins96, CYP1A1 Msp, GSTT1, GSTM1, GSTP gene polymorphisms associated with the susceptibility of peripheral nerve damage. These findings suggested that CYP2E1 gene might increase the susceptibility to n-hexane-induced peripheral damage.

Adult↗

PubMedDate not supplied

Reperfusion injury in burned rats after delayed fluid resuscitation.

Organ failure from ischemic injury is common in deaths that are due to burn when fluid resuscitation is not performed. Organ perfusion after a delay in resuscitation, however, may induce or even accelerate ischemic organ damage. To study this phenomenon, 40 rats were classified (n = 10) to serve as normal control, burn with no resuscitation, burn with early fluid resuscitation, and burn with delayed resuscitation groups. A modified Walker burn model was used to inflict 50% total body surface area scald burns on the rats. Cellular energy metabolism and tissue water content of several vital organs were measured at 8 hours after burn injury. Adenosine triphosphate, total adenine nucleotides, and energy charge in liver, heart, and kidney tissues were significantly lower (p less than 0.05) with delayed fluid resuscitation compared with early resuscitation. Furthermore, in heart and kidney tissues adenosine triphosphate, total adenine nucleotides, and energy charge were significantly lower in the delayed resuscitation group compared with the group that received no fluid resuscitation. This indicates that heart and kidney tissue are more viable at 8 hours after burn injury, with no fluid resuscitation compared with delayed resuscitation. Water content of lung and muscle tissue were significantly lower (p less than 0.05) in the burn group that received no fluid resuscitation compared with that in early and delayed resuscitation groups. Water content of muscle was significantly greater with delayed resuscitation compared with the early resuscitation group. Results indicate that delayed fluid resuscitation in cases of burn shock may disrupt the cellular energy metabolism in some vital organs and cause skeletal muscle edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenine Nucleotides↗

PubMedDate not supplied

Efficacy of leupeptin, superoxide dismutase, and verapamil in modulating delayed reperfusion damage after burn injury.

Reperfusion damage has been identified as an important factor in multiorgan failure after severe burn injury. We wondered if leupeptin, a protease inhibitor, superoxide dismutase (SOD), a scavenger of free oxygen radicals, or verapamil, a calcium antagonist, would protect the cellular energy metabolism when they were given with fluid resuscitation that was delayed 6 hours after a severe burn injury. Fifty male rats weighing 280 to 300 gm received a 50% third-degree scald burn. Ten of these received fluid resuscitation at 30 minutes and 1 1/2 hours after injury, and 40 received delayed fluid resuscitation at 6 and 7 hours after injury. Thirty of these 40 rats were given leupeptin (n = 10), SOD (n = 10), or verapamil (n = 10). Heart, liver, and kidney tissue samples were obtained 8 hours after injury; adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate were measured; and the energy charge potential was calculated. Tissue water content (TWC) in lung and skeletal muscle was also determined. The adenine nucleotide pool and the energy charge potential in heart, liver, and kidney tissue were all significantly decreased (p < 0.01) in rats receiving delayed fluid resuscitation compared with those receiving early resuscitation. Leupeptin was effective in protecting the heart against reperfusion damage, and verapamil and leupeptin showed some efficacy in protecting kidney tissue. Liver tissue, however, showed no protective response with therapy. TWC was significantly decreased (p < 0.01) in skeletal muscle with SOD treatment, and though all treatments appeared to keep lung water content reduced, none was significant at p < 0.01. We thus conclude that both the decreases in heart and kidney adenine nucleotides and the increase in TWC that are caused by delayed fluid resuscitation can be attenuated with appropriate pharmacologic agents.

Adenine Nucleotides↗

PubMedDate not supplied

Superoxide dismutase and leupeptin prevent delayed reperfusion injury in the rat small intestine during burn shock.

Delayed fluid resuscitation during burn shock is thought to compromise the integrity of gut mucosa and allow enteric bacteria to cross the luminal wall and infect other sterile organ systems. Superoxide dismutase, a free-oxygen radical scavenger; leupeptin, a protease inhibitor; and verapamil, a calcium channel blocker, were studied to evaluate their efficacy in maintaining cellular integrity in the gut of thermally burned rats whose fluid resuscitation had been delayed. Fifty male rats weighting 280 to 320 gm were given a full-thickness scald burn covering 50% total body surface area. Ten received early fluid resuscitation beginning half an hour after burn, and 40 received fluid resuscitation delayed by 6 hours. Those receiving delayed resuscitation were given superoxide dismutase (n = 10), leupeptin (n = 10), verapamil (n = 10), or a placebo of normal saline solution (n = 10) at the time of fluid resuscitation. Ileal mucosa samples were harvested, and adenosine triphosphate, diphosphate, and monophosphate were measured. Adenosine triphosphate, total nucleotides, and energy charge potential were significantly lower in the placebo group without therapy compared with those of the early resuscitation group. Superoxide dismutase and leupeptin therapy prevented this drop in cellular energy. Total water content was significantly increased in the placebo group compared with that of the early resuscitation group; superoxide dismutase was able to prevent this increase. Data indicate that intestinal reperfusion injury in burned rats can be effectively modulated with superoxide dismutase or leupeptin therapy.

Adenosine Diphosphate↗

PubMedDate not supplied

Expression of estrogen receptors ERalpha and ERbeta in endometrial hyperplasia and adenocarcinoma.

We assessed the expression of estrogen receptors (ER)alpha and ERbeta in 114 human endometrial hyperplasia and adenocarcinomas. The aim of this study was to determine the expression of both ER isoforms in human endometrial tissue by immunohistochemistry. From normal proliferation to simple and complex hyperplasia, the expression of ERalpha was increased (P < 0.05), while ERbeta did not change much (P > 0.05). In atypia hyperplasia and adenocarcinoma, both ERalpha and ERbeta were decreased significantly (P < 0.05). Most endometrial adenocarcinomas expressed ERalpha, either alone or in combination with ERbeta, and the ERbeta/ERalpha ratio was decreased when compared to normal proliferation (P < 0.05). Also, we found that the expression of ERalpha and ERbeta has no relationship with the status of lymph node of adenocarcinoma (P > 0.05). Both ERalpha and ERbeta play an important role in endometrial hyperplasia and carcinomas, the levels of ERalpha and ERbeta appear be used as prognostic indicators.

Adenocarcinoma↗