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Hyperglycemia is known to cause oxidative stress that leads mainly to enhanced production of mitochondrial reactive oxygen species (ROS). It has been demonstrated that hyperbaric oxygen (HBO) treatment also increases the formation of ROS. There are, however, no comprehensive evaluations of such oxidative effects in diabetes which requires HBO treatment. The purpose of this study is to investigate the influence of a clinically-recommended HBO treatment on glucose homeostasis and oxidative stress in rats with streptozotocin (STZ)-induced diabetes. Under the clinically-used HBO exposure protocol, the levels of blood glucose, thiobarbituric acid reactive substances (TBARS) as a lipid peroxidation marker, and the activity of superoxide dismutase (SOD) as an antioxidant enzyme marker were investigated in the erythrocytes, liver, pancreas, skeletal muscle, and brain of rats with STZ-induced diabetes. The levels of blood glucose and TBARS increased significantly (p<0.05), and the activity of SOD decreased significantly (p<0.05) in the erythrocytes and all organs of rats with diabetes subjected to HBO exposure. These results suggested that HBO exposure might boost glucose autoxidation and increase ROS production in STZ-induced diabetes as side-effects of administering HBO treatment for the first time.

The side effects of hyperbaric oxygen (HBO) treatment, such as oxidative stress and oxygen toxicity, have long been of interest. However, there are no comprehensive studies evaluating such toxic effects in diabetes mellitus (DM). The purpose of this study was to determine the effects of HBO on glucose homeostasis and histological changes in pancreatic β -cells of experimentally induced diabetic rats. A total of 24 male Wistar rats were randomly divided into 4 groups: 1) Control group, no diabetic induction without HBO treatment; 2) HBO group, exposed to 100% oxygen at 2.8 ATA (atmosphere absolute) for 2 h once daily, for 7 days; 3) DM group, diabetes induced by streptozotocin (STZ) injection; and 4) DM + HBO group, received both STZ injection and HBO exposure. HBO treatment, with clinically recommended pressures and duration of therapy, was started on day 5 after STZ injection, when the blood glucose levels were significantly increased. After the last HBO treatment, the pancreatic tissues were immunostained to measure the areas of insulin immunoreactive β -cells in the islets of Langerhans. The blood glucose increased significantly following exposure to HBO, with the highest levels achieved in rats, which had been treated with both HBO and diabetic induction. The area populated with insulin immunoreactive β -cells decreased significantly following diabetic induction and/or HBO exposure, with the smallest area in DM + HBO group. Thus, HBO exposure enhanced the cytotoxic effect of STZ in the β -cells of the pancreas. HBO should be cautiously employed in diabetic patients. hyperbaric oxygen; streptozotocin; diabetic rat; glucose toxicity; oxidative stress. Tohoku

Objective To describe the surgical method, operative time, safety, and usefulness of 3‐port laparoscopic ovariohysterectomy (LOHE) using an ultrasonic coagulation and incision device in dogs <5 kg. Study design Retrospective study. Animals Female dogs (n = 147). Methods Animals were allocated to one of four groups by bodyweight: <2 kg (n = 18), 2–3 kg (n = 37), 3–4 kg (n = 55), and 4–5 kg (n = 37). All surgical procedures were recorded on video. Mean operative time (i.e., time from first skin incision to last suture), clinical variables, hematologic variables, and blood biochemistry were recorded. Intrasurgical and postsurgical complications were recorded, and wound complications, including signs of inflammation or hernia formation were monitored for 3 months. Results The mean operative time for all groups was 18 min, with no significant differences between groups. Eight dogs bled from the mesometrium during surgery. Two dogs had hernia formation at a midline port incision; this complication developed by month 3. No complications such as wound dehiscence or infection of the surgical field were observed at the time of suture removal in any of the dogs. Conclusion We performed LOHE using an ultrasonic coagulation and incision device in dogs <5 kg, and found it to be a safe procedure with minimal complications. Clinical significance We believe that LOHE, using a 3‐port and ultrasonic coagulation and incision device, is a safe, useful, and minimally invasive surgical method for sterilization of dogs <5 kg with minimal complications.