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A Cetin

Publications and source records attributed to A Cetin.

At least 19 recordsLinked to original sources
PubMed2007

Viral vectors: a wide range of choices and high levels of service.

Viruses are intracellular parasites with simple DNA or RNA genomes. Virus life revolves around three steps: infection of a host cell, replication of its genome within the host cell environment, and formation of new virions; this process is often but not always associated with pathogenic effects against the host organism. Since the mid-1980s, the main goal of viral vectorology has been to develop recombinant viral vectors for long-term gene delivery to mammalian cells, with minimal associated toxicity. Today, several viral vector systems are close to achieving this aim, providing stable transgenic expression in many different cell types and tissues. Here we review application characteristics of four vector systems, derived from adeno-associated viruses, adenoviruses, retroviruses and herpes simplex virus-1, for in vivo gene delivery. We discuss the transfer capacity of the expression vectors, the stability of their transgenic expression, the tropism of the recombinant viruses, the likelihood of induction of immunotoxicity, and the ease (or difficulty) of the virus production. In the end, we discuss applications of these vectors for delivery of three molecular systems for conditional mutagenesis, two for inducible transcriptional control of transgenic expression (the tet and the dimerizer systems), and the third one for inducible control of endogenous gene expression based on RNA interference.

Adenoviridae↗
PubMed2006

Plasma levels of nitrites, PGF1alpha, and nitrotyrosine in LPS-treated rats: functional and histochemical implications in aorta.

We investigated the effects of lipopolysaccharide (LPS) administration on plasma nitrite, nitrotyrosine and 6-keto prostaglandin F1alpha, (PGF1alpha) levels and the related resultant changes in function and histochemistry of aorta in rats. Plasma nitrite and PGF1alpha nitrotyrosine levels were analysed after 5 mg/kg intravenous LPS was administered to rats compared with those in non-treated rats. The distribution of nitrotyrosine in the aorta was studied immunohistochemically. The contractile responses of aortic rings to phenylephrine (PE) from both the LPS-treated and control rats were studied in the organ baths. There were increases in plasma nitrite, PGF1alpha, and nitrotyrosine concentrations of LPS-treated rats compared to non-treated rats. Immunoreactivity of nitrotyrosine residues were detected in the endothelial and smooth muscle cells in LPS-treated but not in control rat aorta. The contractile responses to PE of the LPS-treated rat aortic rings were significantly reduced as compared with those of control rat's. Incubation of the aortic rings from LPS-treated rats with cyclooxygenase inhibitor indomethacine or with a combination of indomethacine and nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) increased the contractile responses to the levels observed in control rats suggesting that both prostanoids and particularly nitric oxide (NO) are involved in the reduced contractile responses in LPS-treated rats. These results supported the view that LPS might cause an increment in both NO and PGI2 levels. This increase in the NO and PGI2 levels may be responsible from the reduction in responses of aorta to contractile agents in LPS-treated rats. Increased peroxynitrite formation in LPS-treated rats may lead to nitration of the tyrosil residues of the proteins in the aorta.

Animals↗
PubMed2005

Remifentanil compared with morphine for postoperative patient-controlled analgesia after major abdominal surgery: a randomized controlled trial.

BACKGROUND AND OBJECTIVE: This randomized, double-blinded clinical study was designed to compare the efficacy and safety of remifentanil and morphine administered using intravenous (i.v.) patient-controlled analgesia (PCA) for postoperative analgesia after major abdominal surgery during the first 24 postoperative hours. METHODS: Sixty-nine patients were randomly allocated into two groups, each receiving remifentanil or morphine. The first group received i.v. remifentanil PCA with a loading dose of 45 microg, a maintenance dose of 1 microg min(-1), a bolus dose of 15 microg and a lockout interval of 10 min during the first 24 postoperative hours. The second group received i.v. morphine PCA with a loading dose of 5 mg, a maintenance dose of 0.3 mg h(-1), a bolus dose of 1 mg and a lockout interval of 15 min. Age, weight, sex, history of general anaesthesia, duration of surgery and time spent in the post-anaesthesia care unit were recorded. Preoperative pulse rate, systolic and diastolic blood pressures (BP), respiration rate and arterial blood gases were collected. Pulmonary function was tested before induction of anaesthesia, as well as at 4 and 26 h after operation. Pulse rate, systolic and diastolic BP, respiration rate, arterial blood gases, sedation and visual analogue scores, and presence of side-effects in the recovery room and on the ward for 24 h were recorded at 0, 1, 2, 4, 6, 12, 18 and 24 h after operation. Total drug use, number of boluses delivered, number of boluses demanded and delivery/demand ratio were collected. RESULTS: Sixty patients were evaluated. The groups did not differ in age, weight, sex, history of general anaesthesia, duration of surgery or time spent in the recovery unit. There were also no clinically relevant differences between the groups with regard to haemodynamic and respiratory parameters as well as sedation and visual analogue scores (P > 0.05). More bolus doses were demanded and delivered and the delivery/demand ratio was significantly higher in the remifentanil group (P < 0.05). There was no finding suggesting acute opioid tolerance during remifentanil or morphine PCA. CONCLUSION: The i.v. remifentanil PCA with the chosen dosage regimen after abdominal surgery produces postoperative analgesia and has cardiovascular side-effects similar to those achieved with i.v. morphine. Special attention must be given to respiratory depression during establishment of PCA with remifentanil.

Abdomen↗
PubMed2005

Quantification of the weakness and fatigue in thoracic outlet syndrome with isokinetic measurements.

OBJECTIVES: Patients with thoracic outlet syndrome (TOS) complain of many subjective symptoms that are difficult to measure and quantify. In this study we have tried to assess the weakness (muscle strength) and fatigue (endurance) of these patients with an objective measurement method, isokinetic muscle testing. METHODS: Twenty three TOS patients and 15 age matched healthy controls were enrolled in the study. Detailed histories of the patients were taken and the patients underwent complete physical examinations. Cervical radiographies, Doppler ultrasonography, electromyography, and isokinetic measurements were carried out. The isokinetic measurements were carried using the Biodex System 3 dynamometer during concentric shoulder flexions and extensions at velocities of 60 degrees /s, 180 degrees /s, and 240 degrees /s. RESULTS: Although the muscle strengths of both groups seemed to be similar, the fatigue ratios of TOS patients at 60 degrees /s and 180 degrees /s were found to be higher compared with those of healthy controls (p = 0.029, p = 0.007). CONCLUSIONS: TOS patients were found to have muscular performance similar to controls, but their upper extremities developed fatigue more easily than those of healthy individuals.

Adult↗
PubMed2003

Comprehensive isokinetic knee measurements and quadriceps tendon evaluations in footballers for assessing functional performance.

OBJECTIVES: To ascertain whether detailed isokinetic knee muscle testing reflects the results of other functional measurements in footballers and to look for any correlations between quadriceps tendon thickness and knee strength. METHODS: Ultrasonographic evaluation of the quadriceps tendon (Hitachi EUB-405), isokinetic knee testing (Biodex System 3), and sprint measurements using telemetric photoelectric cells (Chronometre Prosport ESC TX02) were carried out on 29 elite footballers. Jumping capacity was evaluated using Bosco's jumping mat (Ergojump). Anaerobic fitness was assessed by auricular capillary blood lactate measurements (YSI Model 1500 Sport Lactate Analyzer). RESULTS: Quadriceps tendon thickness correlated positively with jumping and sprint measurements and negatively with extensor and flexor strength. However, these correlations did not reach statistical significance. There were significant correlations between knee extensor strength at 60 degrees /s and jumping or sprint measurements and between the extension acceleration values of both knees during isokinetic tests at 240 degrees /s and the sprint measurements. No significant correlation was found between the fatigue ratio values of both knees at 240 degrees /s and the calculated fatigue ratios from the sprint measurements. CONCLUSIONS: Apart from a few variables which correlated with the performance tests, the isokinetic studies did not fully predict the various functional measurements. Neither was there any relation between the quadriceps tendon measurements and the knee strength values nor with the functional performance.

Adolescent↗
PubMed2002

Effects of the temporary clipping in aneurysm surgery on the remnant.

The residual aneurysm rate is reported between 3,8% and 21% in the cases followed after intracranial aneurysm surgery. In the formation of the residual aneurysm, the risk factors include such structural characteristics as the size and lobulation of the aneurysm, posterior circulation, para-ophthalmic localisation and intra-operative rupture. The rates and causes of postoperative residual aneurysms were analyzed in 186 intracranial aneurysm of 160 patients, including the possible effects of temporary clipping on the residual rates. The entire series demonstrated a residual rate of 7%. It was found higher in the large lobulating aneurysms and intra-operative rupture. The residual rate considerably decreased to 4,2% in the aneurysms with temporary clipping. The determination of residual aneurysms, identification of any risk factors and elimination of recoverable factors would allow improvement of surgical results in the treatment of the intracranial aneurysms in the future. Moreover we believe that these will be useful in development of the indications for alternative treatment methods.

Adolescent↗
PubMed2002

Ultrastructure of human umbilical vessels in pre-eclampsia.

OBJECTIVE: Our objective in this study was to investigate the ultrastructure of endothelial and muscle cells of human umbilical vessels in both normal and pre-eclamptic pregnancies. METHODS: Ten umbilical cords from pre-eclamptic (36, 38 and 40 weeks) and four from normal pregnancies (40 weeks) were collected immediately after vaginal deliveries. Umbilical veins and arteries were isolated and fixed in phosphate-buffered 2.5% glutaraldehyde solution (pH 7.2) for 4 h and postfixed with 1% osmium tetroxide at 4 degrees C for 2 h. The sections were embedded in Araldit CY 212. Ultrathin sections were stained with uranyl acetate, examined and photographed. RESULTS: Human umbilical vessel endothelial cells showed ultrastructural changes in pre-eclamptic patients. Weibel-Palade bodies and some organelles such as rough endoplasmic reticulum were found in increased numbers in venous endothelial cells. Accumulations of granular material were detected under the venous endothelium. CONCLUSION: The endothelial and muscle cells of the umbilical vessels from pregnancies complicated by pre-eclampsia showed morphological changes.

Cytoplasm↗
PubMed2001

Inhibitor effect of omeprazole in isolated human myometrial smooth muscle.

The aim of the present study was to investigate the effect of omeprazole, an H+-K+-ATPase inhibitor, in myometrial smooth muscle strips from women undergoing elective caesarean section at term. Isolated myometrial strips taken with informed consent were obtained from eight pregnant women undergoing elective caesarean section at term (not in labour) and mounted in organ baths for recording of isometric tension. We recorded the effect of increasing concentrations of omeprazole on spontaneous and Ca2+-induced contractions of myometrial smooth muscle and on contractions of myometrial smooth muscle pretreated with indomethacin (3 x 10(-6) M) and L-NAME (3 x 10(-5) M). Omeprazole (10(-4)-10(-3) M) decreased the amplitude and frequency of spontaneous contractions in a time- and concentration-dependent manner in all myometrial smooth muscle isolated from pregnant women. The decrease in amplitude of contractions in myometrial smooth muscle reached statistical significance beginning from the concentration of 3 x 10(-4) M. Addition of indomethacin (3 x 10(-6) M) and L-NAME (3 x 10(-5) M) in to the organ baths 30 min before did not change relaxation responses to omeprazole. When 8 mM Ca2+-precontracted in Ca2+-free medium myometrial smooth muscle were exposed to increasing concentrations of omeprazole (10(-5)-10(-3) M), omeprazole produced relaxation responses in a time- and concentration-dependent manner, reaching statistical significance at 10(-4) M. These results show: (1) omeprazole time- and concentration-dependently decreased spontaneous contractile activity in myometrial smooth muscle isolated from pregnant women, (2) omeprazole-induced relaxations was not influenced by indomethacin and N(G)-nitro-L-arginine methyl ester (L-NAME), suggesting that it is not mediated by cyclooxygenase products and nitric oxide, and (3) omeprazole brought about time- and concentration-dependently relaxation of myometrial smooth muscle precontracted by 8 mM Ca2+ in Ca2+-free medium. This effect of omeprazole may be due to blockade of the calcium channels.

Calcium↗
PubMed2001

The role of quantitative ultrasound in predicting osteoporosis defined by dual X-ray absorptiometry.

The aim of this study was to establish whether quantitative ultrasound (QUS) parameters could identify patients classified as osteoporotic and osteopenic on the basis of dual energy X-ray absorptiometry (DEXA). One hundred and twenty-three patients (39 male, 84 female) with osteoporosis and suspected of having osteoporosis were included in this study. Broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured and bone mineral densities (BMD) of the lumbar spine and left hip was measured by DEXA. Subjects were classified into three groups (normal, osteopenic and osteoporotic) on the basis of BMD T-scores measured by DEXA. QUS parameters of the osteoporotic group were significantly lower than those of osteopenic and normal groups; there was no difference in QUS parameters between the normal and osteopenic groups. Correlations of both right and left SOS and BUA with the spine and femoral neck BMD were moderate (r = 0.343-0.539, P < 0.001). There was also reasonable correlation between DEXA and QUS T-scores (r = 0.364-0.510, P < 0.001). QUS had a sensitivity of 21% and a specificity of 95% for diagnosing osteoporosis. We concluded that, although DEXA and QUS parameters were significantly correlated, QUS parameters can not predict osteopenia as defined by DEXA, and sensitivities and specificities of QUS parameters were not sufficiently high for QUS to be used as an alternative to DEXA.

Absorptiometry, Photon↗
PubMed2001

Predictors of bone mineral density in healthy males.

Osteoporosis (OP) is a growing health problem not only in women but also in men. It is well known that men lose bone during aging and are at risk for OP, but the risk factors for OP in men remain controversial. To assess determinants of bone mineral density (BMD) in the spine and femoral neck, 37 healthy men aged 43-73 years were measured using dual photon absorptiometry. Predictors of lumbar spine and femoral neck BMD were determined using multiple linear regression analysis. Backward elimination procedure was used to identify variables significantly related to BMD. The independent variables entered the regression model included age; body mass index (BMI); smoking history; alcohol intake; urinary calcium and hydroxyproline; and serum concentrations of osteocalcin, parathyroid hormone, testosterone, growth hormone, and cortisol. Backward regression analysis indicated that testosterone, cortisol, and BMI were significant predictors of BMD in the lumbar spine while testosterone, hydroxyproline, and osteocalcin were significant predictors of BMD in the femoral neck. Testosterone, cortisol, and BMI accounted for 44% of the total variance in lumbar spine BMD, and testosterone, hydroxyproline, and osteocalcin accounted for 20% of the total variance in femoral neck BMD. These observations suggest that testosterone, cortisol and BMI are determinants of lumbar spine BMD, while testosterone, urinary hydroxyproline, and osteocalcin are determinants of femoral BMD in healthy men.

Adult↗
PubMed2001

Beta-human chorionic gonadotropin and prolactin assays in cervicovaginal secretions as a predictor of preterm delivery.

OBJECTIVE: To evaluate and to compare the predictive value of cervicovaginal beta-hCG and prolactin levels in spontaneous preterm delivery. METHODS: The preterm labor group and normal pregnancy group consisted of 17 and 43 patients between 24 and 36 weeks' gestation, respectively. A single cervicovaginal beta-hCG and prolactin measurement were made in both groups. RESULTS: Cervicovaginal beta-hCG and prolactin levels were significantly higher in the preterm group when compared with those of the term delivery group (P=0.031, P=0.026, respectively). The optimal cut-off value for beta-hCG (27.1 mIU/ml) gave a sensitivity level of 87.5% (47.4-97.9; 95% C.I.) at a specificity of 65.4% (50.9-78.0; 95% C.I.) with positive and negative predictive values of 28% and 97%, respectively. The optimal cut-off value for prolactin (1.8 ng/ml) gave a sensitivity level of 50% (16.0-84.0; 95% C.I.) at a specificity of 96% (86.8-99.4; 95% C.I.) with positive and negative predictive values of 67% and 93%, respectively. CONCLUSIONS: Cervicovaginal beta-hCG measurement in patients with preterm labor may be used as a predictive test. Cervicovaginal prolactin is not a sensitive test compared with the beta-hCG test.

Adult↗
PubMed2001

Unilateral massive ovarian edema and polycystic ovaries. A case report.

Massive ovarian edema is a rare cause of ovarian enlargement in young women. We report a case in a 20-year-old woman with unilateral edema associated with the ultrasound appearance of polycystic ovary disease. Arterial and venous blood flow in the pedicle was observed with color and pulsed wave Doppler examination. Conservative management was successful.

Adult↗
PubMed2001

Unilateral massive ovarian edema in a woman with polycystic ovaries.

Massive ovarian edema is a rare cause of ovarian enlargement in young women. We report the case of a 20-year-old woman with unilateral massive ovarian edema with findings on ultrasound of an enlarged policystic ovary and pedicle arterial and venous blood flow observed with color and pulsed wave Doppler examination. Massive ovarian edema can be managed conservatively and blood flow in the pedicle of the ovary is detected by color and pulsed wave Doppler examination.

Adult↗
PubMed2001

Prevention of postoperative adhesion formation in rat uterine horn model by nimesulide: a selective COX-2 inhibitor.

BACKGROUND: Pelvic surgery is one of the main causes of intraperitoneal (i.p.) adhesions that create various medical problems including pelvic pain, bowel obstructions and female infertility. A rat model was used to investigate the efficacy of nimesulide, a selective cyclooxygenase-2 inhibitor, in the prevention of adhesion formation. METHODS: Fifty Wistar-Albino rats underwent bilateral uterine horn injury with a unipolar cautery. Study groups were as follows: (i) control group, no adjuvant therapy; (ii) i.p. Ringer's lactate group, 2 ml Ringer's lactate solution was instilled i.p.; (iii) i.p. Ringer's lactate plus nimesulide group, 1 ml Ringer's lactate plus 1 ml nimesulide (0.5 mg/ml) were given i.p.; (iv) intramuscular (i.m.) nimesulide group, 1 ml i.m. nimesulide (0.5 mg/ml) was given preoperatively for 5 days; and (v) i.p. nimesulide group, 1 ml nimesulide (0.5 mg/ml) was instilled i.p. At the end of the study all animals were killed, and a standard adhesion scoring system was applied by a blinded examiner. RESULTS: The mean adhesion extent in study groups was as follows: 1.33 +/- 0.76 in control group, 1.40 +/- 0.90 in i.p. Ringer's lactate group, 0.75 +/- 0.70 in i.p. Ringer's lactate plus nimesulide group, 0.25 +/- 0.44 in i.m. nimesulide group and 0.31 +/- 0.70 in i.p. nimesulide group. The mean +/- SD adhesion severities of control, i.p. Ringer's lactate, i.p. Ringer's lactate plus nimesulide, i.m. nimesulide, and i.p. nimesulide groups were 0.58 +/- 0.35, 0.30 +/- 0.41, 0.27 +/- 0.3, 0.12 +/- 0.28 and 0.15 +/- 0.35 respectively. The lowest adhesions were found in the groups treated with nimesulide i.m. and nimesulide i.p. ( P < 0.05). CONCLUSIONS: This study showed that preoperative i.m. or postoperative i.p. administration of nimesulide to the site of injury reduced the formation of postoperative adhesions in a rat uterine horn model.

Animals↗
PubMed2001

Rehabilitation of flexor tendon injuries by use of a combined regimen of modified Kleinert and modified Duran techniques.

OBJECTIVE: Kleinert (active extension, rubber-band passive flexion) and Duran (passive extension, passive flexion) protocols are two basic types of early motion programs for rehabilitation of flexor tendon injuries. Researchers have been working on various modifications or combinations of these two protocols to improve rehabilitation results. The purpose of this study was to analyze the quality of the functional results of flexor tendon repair after a postoperative regimen of early mobilization by use of a combined regimen of modified Kleinert and modified Duran techniques. DESIGN: Thirty-seven patients (74 digits) with repaired flexor tendon injuries were treated. Functional results of the fingers were evaluated by the Buck-Gramcko system and total active motion measurements. RESULTS: The results were excellent in 73% of the fingers, good in 24%, fair in 1.5%, and none was rated poor. CONCLUSION: Our results are comparable with the previous studies that used various postoperative rehabilitation techniques. This postoperative management provides an effective way of achieving satisfactory results. Patient-assisted passive exercises are very safe and more cost effective than therapist-assisted passive exercises.

Adolescent↗
PubMed2000

End-to-side neurorrhaphies of the ulnar and median nerves at the wrist: report of two cases without sensory or motor improvement.

The authors present two unsuccessful clinical cases of end-to-side neurorrhaphy. In the first patient the distal median nerve was coapted in an end-to-side manner to the intact ulnar nerve. In the other patient four cables of sural nerve graft were used to bridge the ulnar nerve and the intact median nerve by two end-to-side coaptations. Neurorrhaphies were performed via epineural sutures through epineural windows. Both of the cases failed to demonstrate any signs of regeneration either clinically or as evidenced by electromyography, Semmes-Weinstein monofilament test, or 256-Hz vibration tests at 18 and 21 months' follow-up respectively.

Adult↗