Impact of Multilevel Surgical Treatment on Mean Platelet Volume in Patients With Obstructive Sleep Apnea Syndrome.

BACKGROUND AND OBJECTIVES: Mean platelet volume (MPV) is a potential marker of platelet reactivity. Increased MPV levels are shown to be the predictor of cardiovascular diseases, hypertension, and stroke. Previous studies demonstrated increased MPV levels in patients with obstructive sleep apnea syndrome (OSAS). The aim of this study was to examine the impact of 1-stage multilevel surgical treatment on MPV levels in patients with OSAS. METHODS: Preoperative and postoperative 6-month hematologic parameters as well as polysomnographic findings of 42 patients, who underwent 1-stage multilevel surgery for treatment of moderate or severe OSAS, were compared. RESULTS: In the comparisons of preoperative and postoperative apnea-hypopnea index (AHI) and MPV values, statistically significant decreases were detected There was a significant positive correlation between the decrease in mean AHI and decrease in MPV levels. CONCLUSIONS: One-stage multilevel surgery targeting the obstruction at the retropalatal and tongue-base levels was found to be effective in decreasing AHI and MPV. Mean platelet volume may be a new index to indicate the success of OSAS surgery.

Does hypercholesterolemia affect the relaxation of the detrusor smooth muscle in rats? In vitro and in vivo studies.

To evaluate the effects of hypercholesterolemia on the relaxation function of the urinary bladder, we examined the physiological mechanisms involved in the isoproterenol-induced relaxation in isolated detrusor strips in vitro and voiding behavior in vivo in rats. Adult male Sprague-Dawley rats were fed standard (control, N = 16) or 4 % cholesterol diet (hypercholesterolemia, N = 17) for 4 weeks. Concentration-response curves for isoproterenol-induced relaxations in carbachol-precontracted detrusor muscle strips were recorded. The contributions of ß2- and ß3-adrenoceptors and ATP-dependent and Ca(2+)-dependent potassium channels to the relaxation response were investigated by using selective adrenergic agonists salbutamol and BRL 37344 and specific potassium channel inhibitors glibenclamide and charybdotoxin, respectively. Cystometrography was performed to assess bladder function. Hypercholesterolemic rats had higher serum cholesterol and low- and high-density lipoprotein levels than the controls with no sign of atherosclerosis. Isoproterenol-induced relaxation was significantly enhanced in the hypercholesterolemia group. Preincubation with the M2 receptor antagonist attenuated the relaxation response in both groups. The relaxation responses to isoproterenol and salbutamol were similar in both groups, while BRL 37344 appeared to produce a greater relaxant effect in the hypercholesterolemic rats. Also, the inhibitory effects of potassium channel inhibitors on relaxation responses were comparable among the groups. The cystometric findings revealed that threshold and basal pressure values were higher in the hypercholesterolemia group compared with controls. We showed that hypercholesterolemia leads to greater relaxation responses to isoproterenol, appears to impair the braking function of M2 cholinergic receptors on adrenoceptor-induced relaxations in the isolated detrusor muscle, and affects the voiding function in rats.

Evaluation of outer hair cell function and medial olivocochlear efferent system in patients with type II diabetes mellitus.

AIM: This study was designed to investigate the function of outer hair cells and medial olivocochlear efferents in type II diabetes mellitus (DM). MATERIALS AND METHODS: There were 50 patients with type II DM and 51 age- and sex-matched healthy controls included in the study. Both groups were compared in terms of transient evoked otoacoustic emissions (TEOAEs), distortion product otoacoustic emissions (DPOAEs), and contralateral suppression of TEOAE. RESULTS: Pure tone thresholds of the patients with type II DM were significantly higher than in the controls (P < 0.05). The TEOAE amplitudes at 1 kHz and at 1.5, 2, 3, 4, and 6 kHz signal-to-noise ratio amplitudes on DPOAE testing were significantly lower in the patients than controls (P < 0.05). There was no significant difference between the type II DM and control groups regarding contralateral suppression test results of TEOAEs. CONCLUSION: Type II DM seems to impact the auditory system at the cochlear level by affecting the functions of outer hair cells, and it results in elevation of the thresholds on audiometry and a decrease in the amplitudes of otoacoustic emissions.

The effects of oral carvacrol treatment against H2O2 induced injury on isolated pancreas islet cells of rats.

Pancreatic islet transplantation is an alternative treatment of insulin replacement therapy in diabetes mellitus, but the islets are exposed to many chemical, mechanical damages, and oxidative stress before transplantation. Carvacrol is a well-known essential oil for its antioxidant, antimicrobial, antifungal and antiinflammatory properties. The aim of this study was to investigate the possible protective effects of carvacrol against H 2O 2 induced cellular injury on isolated pancreas islets. After carvacrol (20, 40 and 80 mg/kg/day) treatment, the pancreas islets were isolated by enzyme digestion. The isolated islets were incubated within 0, 150 and 300 µM H 2O 2 containing medium at +4°C for 15 min. Then, the islets were examined with fluorescein diacetate and propidium iodide mixture stains for viability. A number of islets were stored for lipid peroxidation, protein oxidation and DNA fragmentation analysis. The cell viability ratio of Carvacrol 20 mg/kg/day group was increased in comparison to control and vehicle (DMSO) groups. Additionally, carvacrol application protected the cells from lipid peroxidation and protein oxidation induced by H 2O 2. H 2O 2 caused tissue injury and DNA fragmentation. There was only one DNA fragmentation band from islet cells of 20 mg/kg/day carvacrol treated group, however there were more than one bands from control and DMSO groups. In conclusion, carvacrol treatment ameliorates islet cell injury induced by H 2O 2. However, the dose of carvacrol is important and our results suggest that 20 mg/kg/day dose is more effective than doses of 40 or 80 mg/kg/day.

Effects of tolterodine and trospium chloride on renal damage induced by partial upper urinary tract obstruction.

OBJECTIVE: To examine the efficacy of trospium chloride and tolterodine on the renal parenchymal inflammatory process and upper urinary dilation in rats with chronic partial upper urinary tract obstruction. MATERIALS AND METHODS: A total of 32 rats were divided into 4 groups: group 1, control; group 2, obstruction; group 3, obstruction plus tolterodine; and group 4, obstruction plus trospium chloride. In all groups, except for group 1, partial upper urinary tract obstruction was induced by embedding the upper quarter of the right ureter into the psoas muscle for 14 days. At the end of the experiment, the rats were killed. The catalase, malondialdehyde, and protein carbonyl levels were determined in renal tissue. Tubular dilation and parenchymal inflammation were evaluated using hematoxylin-eosin staining. Smooth muscle actin and cytoglobin were examined with immunohistochemical staining. RESULTS: The obstruction group demonstrated severe pelvic dilation and parenchymal inflammation and increased smooth muscle actin staining in the wall of upper urinary tract (P <.05). The treatment of the rats with tolterodine and trospium chloride markedly attenuated the inflammatory alterations and reduced tubular dilation. This treatment also reduced elevated oxidative stress product levels and restored the depleted renal antioxidant enzyme. CONCLUSION: These findings imply that increased renal pelvic pressure can contribute to renal parenchymal injury in chronic pelvic upper urinary tract obstruction. Antimuscarinic medications such as tolterodine and trospium chloride exert renoprotective effects, probably by prevention of pelvic pressure increases.

The effect of hypercholesterolemia on carbachol-induced contractions of the detrusor smooth muscle in rats: increased role of L-type Ca2+ channels.

To investigate a possible relation between hypercholesterolemia and detrusor smooth muscle function, we studied the contractile response to potassium challenge, carbachol (CCh), and the components of CCh-induced contractile mechanism in high-cholesterol diet-fed rats. Adult male Sprague-Dawley rats were fed with standard (control group, N = 17) or 4 % cholesterol diet (hypercholesterolemia group (HC), N = 16) for 4 weeks. Spontaneous contractions of detrusor muscle strips and their responses to potassium chloride (KCl) or cumulative dose-contraction curves to CCh were recorded. The effects of muscarinic receptor antagonists (methoctramin and/or 4-diphenylacetoxy-N-methylpiperidine), L-type Ca(+2) channel blocker (nifedipine), and/or rho-kinase inhibitor Y-27632 were investigated. Blood cholesterol level was increased in the HC group with no sign of atherosclerosis. The KCl-induced detrusor smooth muscle contractions were higher in HC, whereas spontaneous and CCh-induced responses were similar in both groups. Preincubation with receptor antagonist for M(3) but not for M(2) attenuated contraction significantly, shifting the dose-response curve to the right. This response was similar in both groups. Among two effector mechanisms of M(3)-mediated detrusor smooth muscle contraction, rho-kinase pathway was not affected by hypercholesterolemia, whereas blockade of L-type Ca(+2) channels potently reduced contractions. The results of this study point out a relation between hypercholesterolemia and contractile mechanism of detrusor smooth muscle likely to change urinary bladder function, via altering L-type Ca(+2) channels. Taken together with escalating incidence of hypercholesterolemia and lower urinary tract symptoms, it is a field which deserves to be investigated further.

The effect of oral isotretinoin (13-cis retinoic acid) on hearing systems in patients with acne vulgaris: a prospective study.

Isotretinoin is widely used in the treatment of extensive and nodulocystic acne. The objective of this prospective study was to investigate whether oral isotretinoin could affect the hearing system. Thirty-eight patients with acne vulgaris (76 ears) who were diagnosed and treated at the Department of Dermatology were included in the current study. Study evaluation visits were performed at baseline and at Weeks 1, 2 and 3. Pure-tone averages (PTAs) of air conduction thresholds at 250 Hz (PTA1); 500, 1000, and 2000 Hz (PTA2); 4000, 8000, and 10,000 Hz (PTA3); and 12,500, 16,000, 18,000 and 20,000 Hz (PTA4) for each ear were calculated separately. Assessment of the efficacy was based on the audiometric findings. Compared with pre-treatment evaluation, the PTAs of patients were found to be significantly different at the first week for PTA2 (P = 0.033) and PTA3 (P = 0.001), at the second week for PTA1 (P = 0.036), and at the third week for PTA4 (P = 0.002). Our results suggest that the oral isotretinoin (13-cis retinoic acid), which is a derivative of retinol (vitamin A), improved the hearing level of the patients in all audiometric frequencies in a short-period follow-up.

Audiological findings in celiac disease.

OBJECTIVE: Celiac disease (CD) is a gluten-triggered immune enteropathy caused by a genetic predisposition. Recent papers suggest that CD is increasingly recognized by extraintestinal findings. The aim of this study was to investigate the effect of CD on hearing pathway including the olivocochlear efferent system in children. METHODS: Forty-one pediatric CD patients and 31 controls were included in the study. Both groups were evaluated with audiometry, tympanometry, transiently evoked otoacoustic emission (TEOAE), distortion product otoacoustic emission (DPOAE), and contralateral suppression of the TEOAE. RESULTS: The threshold at 250 Hz of the patients with CD was significantly higher (p < 0.05 in CD compared to control group, p < 0.0001). The signal to noise ratio (SNR) amplitudes in DPOAE testing and the SNR amplitudes with and without contralateral acoustic stimulus in TEOAE testing were significantly lower at 1,000 Hz in the CD compared to the control group. There was no significant difference between the CD and the control group regarding contralateral suppression amplitudes. CONCLUSION: CD seems to have an important impact on the auditory system, and results in an elevation of the thresholds at 250 Hz on audiometry and a decrease in the amplitudes of DPOAE and linear TEOAE at 1,000 Hz in children.

Effect of toluene on erythrocyte membrane stability under in vivo and in vitro conditions with assessment of oxidant/antioxidant status.

Toluene, an organic solvent used widely in the industry, is highly lipophilic and accumulates in the cell membrane impeding transport through it. Its metabolites cause oxygen radical formation that react with unsaturated fatty acids and proteins in erythrocytes leading to lipid peroxidation and protein breakdown. In this study, we aimed to investigate the membrane stabilizing and the oxidative stress-inducing effects of toluene in human erythrocytes. Measurements of osmotic fragility, mean corpuscular volume (MCV), oxidative stress parameters and antioxidant enzyme activities were performed simultaneously both in individuals exposed to toluene professionally (in vivo) and human erythrocytes treated with toluene (in vitro). To measure osmotic fragility, erythrocytes were placed in NaCl solutions at various concentrations (0.1% [blank], 0.38%, 0.40%, 0.42%, 0.44%, 0.46%, 0.48% and 1% [stock]). Percentage of haemolysis in each solution was calculated with respect to the 100% haemolysis in the blank solution. The erythrocyte packs prepared at the day of the above-mentioned measurements were kept at -80 degrees C until the time for determination of malonyldialdehyde and protein carbonyl levels, and catalase (CAT) and glutathione peroxidase activities as indicators of oxidative stress. Toluene increased oxidative stress parameters significantly both in vivo and in vitro; it also caused a significant decrease in the activities of antioxidant enzymes. Osmotic fragility was altered only in the case of in vitro exposure. In conclusion, toluene exposure resulted in increased lipid peroxidation and protein damage both in vivo and in vitro. Although, it is natural to expect increased osmotic fragility due to oxidative properties of toluene, its membrane-stabilizing effect overcame the oxidative properties leading to decreased osmotic fragility or preventing its deterioration in vitro and in vivo toluene exposures, respectively, in the present study.

The effect of swimming exercise on lipid peroxidation in the rat brain, liver and heart.

We intended to study the effect of swimming exercise on the brain, liver and heart malondialdehyde (MDA) levels which are the last product of oxidation, and to compare them with the brain, liver and heart MDA levels of controls. The experiments were carried out on 20 Wistar rats which were fed with a standard laboratory chow diet ad libitum. Rats were distributed in two groups, control group (n = 10) and exercise group (n = 10). The exercise group rats were exposed to swimming exercise for 30 minutes. After this animals in each group were sacrificed by decapitation, their brain, liver and heart tissues were quickly removed. MDA levels of the brain, liver and heart were determined according to the method in which MDA reacts with thiobarbituric acid. Results were evaluated by the Mann-Whitney U test. The liver and heart MDA levels in the exercise group were (29.59+/-6.73 and 10.49+/-1.90 nmol/g tissue, respectively) significantly higher than in the control group (21.78+/-3.46 and 8.86+/-1.25 nmol/g tissue, p<0.01 and p<0.05, respectively). However, the brain MDA levels were similar in both groups (exercise group 19.37+/-5.50 nmol/g tissue and control group 16.58+/-2.44 nmol/g tissue; p=0.325). It is concluded that swimming exercise might cause oxidative stress.

Transmission electron microscopy study of the effects of zinc overdose on mouse liver tissue.

Thirty adult male mice were divided into three groups. The animals in group I were used as controls and drank only water during the entire period of experimentation. Group II animals drank water containing 1.5 g/100 mL zinc as ZnSO4, and group III animals received 2.5 g/100 mL zinc. After 3 wk supplementation with high doses of zinc, the animals were killed and the livers were removed and examined by electron microscopic techniques. After the supplementation period, the animals in groups II and II showed various degrees of degenerative changes in the hepatocytes, such as increased size and the presence of spaces and an abundance of lipid globules in the cytoplasm. The mitochondria showed a crystalline appearance, a diluted matrix, and dense aggregations. Some smooth endoplasmic reticulum tubules showed dilation and were filled with a dense substance. None of these changes were present in the group I control animals.