The Effect of Acute Aerobic Exercise on Redox Homeostasis and Mitochondrial Function of Rat White Adipose Tissue.

Physical exercise is characterized by an increase in physical and metabolic demand in face of physical stress. It is reported that a single exercise session induces physiological responses through redox signaling to increase cellular function and energy support in diverse organs. However, little is known about the effect of a single bout of exercise on the redox homeostasis and cytoprotective gene expression of white adipose tissue (WAT). Thus, we aimed at evaluating the effects of acute aerobic exercise on WAT redox homeostasis, mitochondrial metabolism, and cytoprotective genic response. Male Wistar rats were submitted to a single moderate-high running session (treadmill) and were divided into five groups: control (CTRL, without exercise), and euthanized immediately (0 h), 30 min, 1 hour, or 2 hours after the end of the exercise session. NADPH oxidase activity was higher in 0 h and 30 min groups when compared to CTRL group. Extramitochondrial ROS production was higher in 0 h group in comparison to CTRL and 2 h groups. Mitochondrial respiration in phosphorylative state increased in 0 h group when compared to CTRL, 30 min, 1, and 2 h groups. On the other hand, mitochondrial ATP production was lower in 0 h in comparison to 30 min group, increasing in 1 and 2 h groups when compared to CTRL and 0 h groups. CAT activity was lower in all exercised groups when compared to CTRL. Regarding oxidative stress biomarkers, we observed a decrease in reduced thiol content in 0 h group compared to CTRL and 2 h groups, and higher levels of protein carbonylation in 0 and 30 min groups in comparison to the other groups. The levels returned to basal condition in 2 h group. Furthermore, aerobic exercise increased NRF2, GPX2, HMOX1, SOD1, and CAT mRNA levels. Taken together, our results suggest that one session of aerobic exercise can induce a transient prooxidative state in WAT, followed by an increase in antioxidant and cytoprotective gene expression.

There are no three physiological narrowings in the upper urinary tract: a new concept of the retroperitoneal anatomy around the ureter.

The widely held dogma of three physiological narrowings in the upper urinary tract has proven incorrect by recent several studies using computed tomography images. There are only two common obstruction sites: the upper ureter and the ureterovesical junction. The second narrowing, where the ureter crosses the iliac vessels, cannot be regarded anymore as a common obstruction site. The mechanism by which stones lodge in the upper ureter is explained anatomically by the change in ureteral mobility and compliance at the level where the ureter exits the perirenal space. This level can be identified radiologically as the point where the ureter crosses under the ipsilateral gonadal veins, termed the "crossing point". Kinking of the upper ureter is another manifestation of this anatomical phenomenon, visible in radiological images. It is caused by loosening of the ureter at or above the crossing point (within the perirenal space), corresponding with renal descent such as during the inspiratory phase. This new anatomical discovery in the retroperitoneum will not only bring about a paradigm shift in terms of the physiological narrowings in the upper urinary tract, but may also lead to the development of new surgical concepts and approaches in the area.

[Anatomy and physiology of autonomic pelvic innervations].

Autonomic innervation is responsible for the correct function of the organs in the pelvis. Retroperitoneal surgery is associated with trauma of the nerve structures. For this reason a detailed knowledge of topographic anatomy of the pelvis is needed, when surgery for oncological diseases or endometriosis is performed. Faster recovery, decrease of the number of postoperative complications and a better quality of life are the result of the nerve-sparing approach.

The prevesical space: anatomical review and pathological conditions.

The prevesical space is the largest potential space within the pelvic extraperitoneal space. Located anterosuperior to the bladder, it has complex communications with the adjacent pelvic extraperitoneal spaces, rectus sheath, and retroperitoneum. The prevesical space is also the site of various pathological processes, and can act as a conduit for the spread of these conditions. Therefore, awareness of the detailed anatomy and potential routes of communication may help radiologists in making accurate diagnoses of pathological conditions involving the prevesical space.

Assessment of the use of temperature-sensitive microchips to determine core body temperature in goats.

Body temperature was measured at five different body sites (retroperitoneum, groin, semimembranosus muscle, flank and shoulder) using temperature-sensitive microchips implanted in five female goats, and compared with the core body and rectal temperatures. Body temperature was measured while the goats were kept in different ambient temperatures, with and without radiant heat, as well as during a fever induced experimentally by injection of bacterial lipopolysaccharide. Bland-Altman limit of agreement analysis was used to compare the temperature measurements at the different body sites during the different interventions. Temperatures measured by the microchip implanted in the retroperitoneum showed the closest agreement (mean 0.2 °C lower) with core and rectal temperatures during all interventions, whereas temperatures measured by the microchips implanted in the groin, muscle, flank and shoulder differed from core body temperature by up to 3.5 °C during the various interventions.

Respiration-induced kidney motion on cobalt-chromium stent fatigue resistance.

During normal breathing, the kidneys move up and down due to the diaphragm motion and the renal artery subsequently experiences bending at or close to its point of fixation to the aorta. The impact of this kidney motion on implanted stent fatigue performance was not well understood in the past. Previous study from the authors on an 18-mm long single cobalt-chromium stent showed that the change in bending angle was minor during simulated respiration-induced kidney motion on cadavers. Finite Element Analysis revealed excellent fatigue resistance of the studied cobalt-chromium stent under simulated respiratory motion for the single stent configuration. In this article, the study was extended further to the overlapped stent configuration where a physician deploys two stents overlapping at the stent ends to fully cover a long lesion. Fluoroscopic images showed that the change in bending angle during simulated respiration-induced kidney motion on cadavers was more significant when two cobalt-chromium stents were overlapped. Calculated data of the Goodman analysis for the overlapped stents migrated toward the Goodman diagram failure line, indicating lower fatigue resistance during respiration when compared to a single stent.

The retroperitoneum protects prosthetic graft material from intraperitoneal contamination: an experimental study.

OBJECTIVES: To evaluate the ability of the retroperitoneum to serve as a barrier, against bacterial contamination, between the peritoneal cavity to the retroperitoneal space. METHODS: Seventy rats had a small piece of knitted Dacron graft placed in the retroperitoneal space and 10(6)-10(9) colony forming unit (cfu) Enterococcus faecalis was injected into the peritoneal cavity. In half the retroperitoneal (RP) group, the retroperitoneum was preserved and in the remainder, the open peritoneal (OP) group, needle holes were created. Grafts were harvested after 1, 4, or 7 days and cultured for E. faecalis. A blood sample was collected from three rats in each group for culture before the graft was harvested. RESULTS: Graft infection did not develop in any rat injected with 10(6) or 10(7) cfu in the RP group, while seven out of the 10 graft cultures of the OP group grew E. faecalis (P = 0.003). In rats injected with 10(8) or 10(9) cfu, five out of the 10 graft cultures in the RP group and eight out of 10 in the OP group grew E. faecalis. All blood cultures were negative when the injected bacterial count was 10(7) cfu or less. One out of the three blood cultures was positive at 10(8) cfu, and all were positive at 10(9) cfu. CONCLUSIONS: These results suggest that an intact retroperitroneum acts as a protective barrier against intraperitoneal bacterial contamination, particularly when blood cultures are negative.

mRNA levels of SREBP-1c do not coincide with the changes in adipose lipogenic gene expression.

Physiological differences in lipid metabolism exist according to adipose sites. To delineate at which step such gene regulation could occur, mRNA levels of various proteins involved in the overall lipogenic process were determined in subcutaneous (SC) and retroperitoneal (RP) adipose tissues. Fatty acid synthase, malic enzyme, ATP citrate lyase, insulin-sensitive glucose transporter, and glucose-6-phosphate dehydrogenase mRNA levels were coordinately reduced (by up to 50-fold) during fasting in RP and in SC relative to fed rats, and restored or overexpressed (by up to 5- to 6-fold) during refeeding. The response was most often delayed and lower in SC compared to RP. This could contribute to site-specific differences. Interestingly, SREBP-1c mRNA levels were markedly decreased by fasting in SC but remained unchanged in RP. Refeeding tended to restore levels close to fed group values. We conclude that mRNA levels of SREBP-1c do not coincide with the expected changes in adipose lipogenic gene expression of fasted/refed rats.

Effect of heated and humidified carbon dioxide gas on core temperature and postoperative pain: a randomized trial.

BACKGROUND: Intraoperative hypothermia is a common event during laparoscopic operations. An external warming blanket has been shown to be effective in preventing hypothermia. It has now been proposed that using heated and humidified insufflation gas can prevent hypothermia and decrease postoperative pain. Therefore, we examined the extent of intraoperative hypothermia in patients undergoing laparoscopic Nissen fundoplication using an upper body warming blanket. We also attempted to determine whether using heated and humidified insufflation gas in addition to an external warming blanket would help to maintain intraoperative core temperature or decrease postoperative pain. METHODS: Twenty patients were randomized to receive either standard carbon dioxide (CO2) gas (control, n = 10) or heated and humidified gas (heated and humidified, n = 10). After the induction of anesthesia, an external warming blanket was placed on all patients in both groups. Intraoperative core temperature and intraabdominal temperature were measured at 15-min intervals. Postoperative pain intensity was assessed using a visual analogue pain scale, and the amount of analgesic consumption was recorded. Volume of gas delivered, number of lens-fogging episodes, intraoperative urine output, and hemodynamic data were also recorded. RESULTS: There was no significant difference between the two groups in age, length of operation, or volume of CO2 gas delivered. Compared with baseline value, mean core temperature increased by 0.4 degrees C in the heated and humidified group and by 0.3 degrees C in the control group at 1.5 h after surgical incision. Intraabdominal temperature increased by 0.2 degrees C in the heated and humidified group but decreased by 0.5 degrees C in the control group at 1.5 h after abdominal insufflation. There was no significant difference between the two groups in visual analog pain scale (5.4 +/- 1.6 control vs 4.5 +/- 2.8 heated and humidified), morphine consumed (27 +/- 26 mg control vs 32 +/- 19 mg heated and humidified), urine output, lens-fogging episodes, or hemodynamic parameters. CONCLUSION: Heated and humidified gas, when used in addition to an external warming blanket, minimized the reduction of intraabdominal temperature but did not alter core temperature or reduce postoperative pain.

Anatomy of the peritoneal aspect of the deep inguinal ring: implications for laparoscopic inguinal herniorrhaphy.

There are a number of important structures to be avoided in suturing or stapling during laparoscopic inguinal herniorrhaphy, not all of which are easily identifiable at laparoscopy. This is particularly so of the ductus deferens. Measurements were taken of the angle made by the ductus deferens with testicular vessels, and of the thickness of tissue in the vicinity of the internal ring into which sutures or staples are likely to be inserted. The angle (mean +/- SD) made by the ductus with testicular vessels was 38.6 degrees +/- 4.4 degrees on the right, and 48.6 degrees +/- 7.2 degrees on the left (P < 0.05) (measurements for right and left sides taken from different cadavers). Thickness of tissue around the ring (peritoneum, transversalis fascia and intervening connective tissue) varies at different sites, being greatest lateral to the testicular vessels (2.2 +/- 0.4 mm) and least over the ductus (0.2 +/- 0.1 mm). The angle measured constitutes the apex of the "triangle of doom" (Spaw et al., 1991. J. Laparoendoscopic Surg. 1:269-277) and with its use the position of the ductus deferens may be predicted and the underlying external iliac vessels avoided when stapling during herniorrhaphy.

Body fat reserves attenuate gastric ulcers induced by restricted feeding in rats.

The purpose of this experiment was to explicitly test the hypothesis that the depletion of fat reserves is a critical factor in the generation of ulcers in the glandular stomach. Fat reserves were systematically manipulated by using chow vs. high-fat diets and by using rats of different ages (3, 7, and 17 months). The ulcerogenic procedure consisted of limiting food intake to 6 g of chow per day. For chow-fed rats, 20 days were required to induce ulcers in 3-month-old rats whereas more than 40 days were required in 7- and 17-month-old rats. In 7-month-old rats fed a high-fat diet, the ulcerogenic phase lasted 63 days. Virtually no ulcers were found in control groups with larger body weights that were yoked to the duration of the ulcerogenic phase. Measurement of retroperitoneal and epididymal fat pads indicated that these were nearly depleted in rats with ulcers whereas some fat remained in ulcer-free rats, regardless of age, diet, or the duration of the ulcerogenic phase. These results suggest that the depletion of fat reserves to a critical level triggers a metabolic stress response that then produces gastric ulcers.

Is the intrinsic bladder pressure a reliable parameter?

Simultaneous pressure recording in different organs shows that voluntary movements as straining, Valsalva maneuver, cough, are easy recognizable. Spontaneous pressure waves in the rectum may give the impression of uninhibited bladder contractions if subtracted from the total bladder pressure.