Laparoscopic "second-look" in the management of mesenteric ischemia

Mesenteric ischemia is a major cause of mortality in surgery. Despite the advances in medicine, considerable number of patients undergoes reoperations for a better assessment of intestinal viability. Although great majority of these second-look operations are "negative explorations," progressive nature of this devastating disease pushes surgeons to re-explore the abdomen. This study compares open and laparoscopic "second-look" procedures in patients with mesenteric ischemia. In the first group (n = 41), abdomen was closed and second-look laparotomy was performed to 23 patients. In the second group (n = 36), a 10-mm trocar was inserted before closing the abdomen and second-look intervention was performed by a telescope to 23 patients. Sixteen of relaparotomies in the first group (70%) revealed nothing and were unnecessary. Two patients (8%) in the laparoscopy group needed re-resection while 20 patients (87%) were rescued from unnecessary laparotomies. Conclusively, patients with mesenteric ischemia are "ill enough" to deserve the "minimal invasion" spirit of laparoscopic surgery.     

A correction procedure for the volume conductor effect in the compound action potential recorded from isolated nerve trunk

The shape and magnitude of the compound action potential (CAP), which is the linear summation of the single fiber action potentials, depend strongly on the recording conditions. Volume conductor effect should be eliminated or corrected in order to get reliable information about the functional state of the nerve trunk. In the case of monophasic extracellular recordings, the integral of CAP recorded extracellularly tends to decrease with the distance, because the extracellular resistance between the stimulating and recording electrodes changes. To compensate for this effect, we took into account the spatial deviation of the integral of CAP versus distance and defined a spatial correcting factor, g(x). By applying g(x) to all CAPs, we get corrected CAP (cCAP) data for further evaluations. It is well known that the slope of the maximum derivative of CAP versus distance curve would be a measure of conduction velocity distribution for the fast conducting nerves in a nerve trunk. The slopes of these curves for extracellular and suction techniques on the same nerves are compared; we concluded that the difference between the two techniques was not important for the correction procedure on extracellular records.     

Unilateral brachial plexus injury occurring after reduction mammaplasty

A left neuropraxic brachial plexus injury was seen after reduction mammaplasty. The clinical signs of plexopathy were noted in the very early postoperative period. The partial axonal damage was heavy in the upper and posterior branches and moderate in the medial branch of the plexus. The hyperabduction of the upper extremity during the surgery was thought to be the main cause. With a close followup and extensive physiotherapy, in addition to B complex vitamins, a full recovery was achieved at the end of the tenth week.     

Antioxidant vitamin levels in term and preterm infants and their relation to maternal vitamin status

BACKGROUND: Lipid peroxidation plays a vital role in the pathogenesis of many neonatal complications. Preterm babies are especially predisposed to lung diseases and retinopathy, probably due to a deficiency in their antioxidant systems. Vitamins E, A, and C are part of the natural antioxidant defense systems. We aimed to determine the levels of vitamins E, A, and C in maternal and cord blood plasma of term and preterm infants and to investigate the relationships between these levels. METHODS: In the present study we determined vitamin E, A, and C levels in the umbilical cord blood of term (n = 30) and preterm (n = 22) infants and their mothers by HPLC. Blood samples were taken during delivery. RESULTS: Levels of lipid soluble antioxidant vitamin E and A in cord blood were lower than maternal values (p <0.01, p <0.05, respectively). Conversely, the level of water-soluble vitamin C was higher in cord blood than in maternal level (p <0.05). Significantly higher levels of vitamins E, A, and C were found in term babies as compared with those born preterm (p <0.05). CONCLUSIONS: There was a positive correlation between maternal and cord blood levels of vitamins E and A (r = 0.775, r = 0.725, respectively). In conclusion, preterm babies have fewer lipid-soluble antioxidant vitamins in their serum compared to term infants. Therefore, it is possible to postulate that preterm infants are more susceptible to oxidative stress.     

Insulin increases homocysteine levels in a dose-dependent manner in diabetic rats

BACKGROUND: Even moderate increases in levels of homocysteine cause cardiovascular degeneration. Various genetic and nutritional factors affect plasma homocysteine concentrations, and hyperhomocysteinemia damages vascular endothelial cells; hence their functions are disrupted. In diabetes mellitus, homocysteine metabolism is altered and as a result, more severe diabetic complications are expected when hyperhomocysteinemia occurs. METHODS: In the present study we experimentally induced diabetes in rats and examined effects of low or high dose of insulin administration on homocysteine metabolism. RESULTS: We determined that homocysteine levels were reduced in STZ-induced diabetic rats. This reduction was normalized by insulin in a dose-dependent manner. On the other hand, increased levels of lipid parameters (cholesterol, triglycerides, HDL) were reduced by insulin. CONCLUSIONS: Hcy level in experimentally induced insulin-dependent diabetes mellitus is decreased and injection of insulin normalizes Hcy levels in a dose-dependent manner. We speculate that insulin increases activities of enzymes of transsulfuration and remethylation reactions and hence speeds up conversion of Hcy to methionine and cysteine.     

Sexually dimorphic cognitive style, female sex hormones, and cortical nitric oxide

Recent studies using the water maze (WM) found marked sex differences in behavioral strategy employed in place learning tasks in adult rats. When a change in the platform position is introduced following learning the place of a platform (visible or hidden) in a different position, female rats escape to the newly positioned visible platform faster than males. Nitric oxide (NO) is implicated in place learning, and there are regional sex differences in its stable metabolites, NO(2)(-)+NO(3)(-), in rat brain. Furthermore, NO(2)(-)+NO(3)(-) levels are sensitive to ovariectomy in female rats. The effect of sex hormones on brain development and function is well documented. The present study was undertaken to study the effects of ovariectomy and hormonal manipulations on cognitive performance in a WM task designed to test differences in behavioral strategy in Sprague-Dawley rats (n=48) of both sexes. Some of the females rats were ovariectomised and received either hormone replacement (estrogen or progesterone alone or in combination) or the vehicle. Cortical and hippocampal NO(2)(-)+NO(3)(-) levels were determined after behavioral testing. There were no group differences in cognitive ability or non-cognitive factors such as motivation or swim speed. Males and intact females differed in their cognitive style, but hormonal manipulations in female rats did not affect this relative use of behavioral strategy. There was a correlation between performance on the trial where sex differences were most prominent and NO(2)(-)+NO(3)(-) levels in the cortex. Our results suggest that the activational effects of circulating gonadal hormones do not play a major role in sexually dimorphic cognitive styles.     

The effects of bumetanide on human umbilical artery contractions

The authors investigate the effect of bumetan ide, an inhibitor of NKCC1 and a loop diuretic, on the tone of human umbilical artery (HUA). Rings of HUA (n = 35) from vaginal deliveries were suspended for isometric tension recordings in organ baths. Cumulative concentration-response curves to serotonin, histamine, and KCl were performed in the absence (control) or in the presence of bumetanide. The relaxant effect of bumetanide was also evaluated in serotonin- and histamine-induced contractions. Bumetanide inhibited HUA tone in serotonin- and histamine-induced contractions with significant changes in the potency (pD(2)) and maximum contractile response (E(max)) values. However, only pD( 2) values for KCl-induced contraction significantly changed in the presence of bumetanide. Bumetanide caused concentration-dependent and sustained relaxations in serotonin-induced contraction; however, there was refractoriness in histamine-induced contraction. These findings raise the possibility that NKCC1 may play a role in the regulation of the umbilical artery tone.     

Lumbar spinal surgery for sciatica due to intervertebral disc disease in the elderly

This report reviews 36 patients aged 71 to 93 years who had lumbar spinal surgey for sciatica pain some with motor and or sensory disturbances and with no motor and sensory disturbances. Even though we found soft disc herniations, these patients should have a thorough circumferential decompression because of bony osteophytes and facet hypertrophy. Special attention is drawn to the removal of herniated discs associated with massive spondylotic degenerative changes.     

Pelvic ganglioneuroblastoma totally excised using posterior sagittal and abdominal approach

Neuroblastoma usually presents as an upper abdominal mass arising from the adrenal gland. Recent experience with neuroblastoma of the spermatic cord, bladder, and pelvis demonstrates the propensity of this tumor to arise in unusual areas. A 1-year-old boy was admitted with pollakiuria, acute urinary retention, and chronic constipation. Computed tomographic and ultrasonographic examinations revealed a 5×5.5×4-cm pelvic mass, which was totally excised using a posterior sagittal and abdominal approach. The pathologic diagnosis was ganglioneuroblastoma and 1-year follow-up was uneventful.     

Relationship between components of heart rate variability and Doppler echocardiographic indices of left ventricular systolic performance in patients with coronary artery disease

Decreased heart rate variability (HRV) has been reported as prognostic predictor in coronary artery disease population. The aim of the study was to assess the relationship between cardiac autonomic tone disturbances and the degree of left ventricular dysfunction, estimated by 2-dimensional and Doppler echocardiography, in patients with coronary artery disease. Forty patients with angiographically proven coronary artery disease and 15 age-and sexmatched healthy subjects were included into the study (Group I and II, respectively). Routine clinical examinations, electrocardiography, coronary angiography, and 2-dimensional and Doppler echocardiography with assessment of LV systolic performance were done in all the patients and control subjects. Cardiac autonomic function was assessed by means of frequency-domain analysis of heart rate variability. The powers of LF and HF bands (P1 and P2), their ratio (P1/P2), and the logarithmic expression of powers were measured. The patients (Group I) had lower values of parasympathetic band of HRV and higher sympathetic activity than the healthy population (Group II) (p<0.0002 for P2 andp<0.04 for P1/P2 ratio). A positive significant correlation was seen between parasympathetic band of HRV and ejection fraction (r=0.61,p<0.0001), and mean acceleration of aortal flow (r=0.56,p<0.0001), whereas P1/P2 ratio inversely and significantly correlated with the same parameters (r=–0.46,p<0.002 and r=–0.41,p<0.008).