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R Tuncer

Publications and source records attributed to R Tuncer.

At least 37 records · Page 2Linked to original sources
PubMed1999

NOX, a novel nitric oxide scavenger, reduces bacterial translocation in rats after endotoxin challenge.

Endotoxemia promotes gut barrier failure and bacterial translocation (BT) by upregulating inducible nitric oxide synthase (iNOS) in the gut. We hypothesized that administration of a dithiocarbamate derivative, NOX, which scavenges nitric oxide (NO), may reduce intestinal injury and BT after lipopolysaccharide (LPS) challenge. Sprague-Dawley rats were randomized to receive NOX or normal saline via subcutaneously placed osmotic pumps before or after LPS challenge. Mesenteric lymph nodes, liver, spleen, and blood were cultured 24 h later. Transmucosal passage of Escherichia coli C-25 or fluorescent beads were measured in an Ussing chamber. Intestinal membranes were examined morphologically for apoptosis, iNOS expression, and nitrotyrosine immunoreactivity. NOX significantly reduced the incidence of bacteremia, BT, and transmucosal passage of bacteria and beads when administered before or up to 12 h after LPS challenge. LPS induced enterocyte apoptosis at the villus tips where bacterial entry was demonstrated by confocal microscopy. NOX significantly decreased the number of apoptotic nuclei and nitrotyrosine residues. NOX prevents LPS-induced gut barrier failure by scavenging NO and its toxic derivative, peroxynitrite.

Animals↗
PubMed1999

Spinal intradural arachnoid cysts located anterior to the cervical spinal cord. Report of two cases and review of the literature.

The authors describe two rare occurrences of radiographically, surgically, and pathologically confirmed spinal intradural arachnoid cysts (not associated with additional pathological entities) that were located anterior to the cervical spinal cord. These lesions have been reported previously in only eight patients. The patients described in this report were young adults who presented with progressive spastic tetraparesis shortly after sustaining mild cervical trauma and in whom no neurological deficit or bone fracture was demonstrated. The presence of an intradural arachnoid cyst was detected on postcontrast computerized tomography (CT) myelography and on magnetic resonance imaging; both diagnostic tools correctly characterized the cystic nature of the lesion. Plain radiography, plain tomography, and contrast-enhanced CT scans were not diagnostic. In both cases a laminectomy was performed, and the wall of the cyst was excised and fenestrated with subarachnoid space. Postoperatively, the patients made complete neurological recoveries. Based on a review of the literature, arachnoid cysts of the spinal canal may be classified as either extra- or intradural. Intradural arachnoid cysts usually arise posterior to the spinal cord in the thoracic spine region; however, these cysts very rarely develop in the cervical region. The pathogenesis of arachnoid cysts is unclear, although congenital, traumatic and inflammatory causes have been postulated. The authors believe that the formation of an arachnoid cyst cannot be explained by simply one mechanism because, in some reported cases, there has been accidental or iatrogenic trauma in association with congenital lesions. They also note that an intradural arachnoid cyst located anterior to the cervical spinal cord is an extremely rare disorder that may cause progressive myelopathy; however, the postoperative prognosis is good.

Adolescent↗
PubMed1998

Immunoglobulin A supplementation abrogates bacterial translocation and preserves the architecture of the intestinal epithelium.

BACKGROUND: Breast milk has been shown to prevent gut-origin infections in neonates through undefined mechanisms. Putative protective factors in breast milk include immunoglobulin (Ig)A, IgG, and lactoferrin. We examined their role in bacterial translocation in neonatal rabbits. METHODS: IgA, IgG, and lactoferrin were isolated from rabbit breast milk through gel filtration and ion-exchange chromatography. Neonates were randomized to receive breast milk, formula alone, or formula supplemented with IgA, IgG, or lactoferrin. Quantitative cultures were performed on day 7 for bacterial translocation. Hematoxylin-eosin-stained sections of distal ileum were examined by light microscopy. Transmucosal bacterial passage was determined in vitro, and the ileal mucosal membranes were examined by confocal microscopy. RESULTS: IgA supplementation abrogated bacterial translocation. IgG and lactoferrin had no significant effect. Neonates that received IgA or breast milk gained more weight than those in the other groups. IgA reduced transmucosal bacterial passage in vitro. In contrast to the normal-appearing distal ileum of neonates fed breast milk, intestinal epithelium from neonates that received formula or formula with IgG or IgA demonstrated prominent vacuoles by light microscopy. Those fed formula alone or formula with lactoferrin had slightly shortened villi. CONCLUSIONS: IgA supplementation prevents bacterial translocation by enhancing gut mucosal barrier function.

Animals↗
PubMed1997

Post-traumatic bilateral diffuse cerebral swelling.

This study confirms that bilateral diffuse cerebral swelling with or without parenchymal haemorrhages (< 15 cc) is a more common occurrence in the paediatric patients with severe head injury as compared with adults, since the analysed sample represented 42.55% and 20.43% of all paediatric and adult patients with severe head injury recorded in our clinic at the time of the study, respectively. The incidence of patients with diffuse cerebral swelling without parenchymal haemorrhages was found to be 27.65% of paediatric patients and 5.37% of adult patients with severe head injury. Secondary neurological deterioration occurred only in 5 (12.5%) paediatric patients and in 4 (10.5%) adult patients with diffuse cerebral swelling and was not to be found associated with parenchymal haemorrhages. A better outcome was seen in paediatric patients. Mortality rates were 12.5% in paediatric patients and 34.21% in adult patients. Our data also suggest that the mortality rate between paediatric and adult patients with diffuse cerebral swelling without parenchymal haemorrhages was similar (15.38% and 20% in paediatric and adult group, respectively), while the adult patients with diffuse cerebral swelling associated with small intraparenchymal haemorrhages have a worse prognosis than paediatric patients.

Adolescent↗
PubMed1997

Conservative management of extradural haematomas: effects of skull fractures on resorption rate.

In conservative management of extradural haematomas (EDH), several mechanisms were described to explain the resorption of the haematoma. One of these was the transfer of the clot into the epicranial space through the skull fracture. In this study, the effects of skull fracture and associated intracranial lesions in the conservative management of EDH were investigated. Skull fracture and associated intracranial lesions were found in 71.11% and 51.1% of the patients, respectively. Resorption rate was calculated using an original formula and it was 0.548 +/- 0.227 in patients with skull fracture and 0.507 +/- 0.170 in patients with both skull fractures and additional intracranial lesions. These rates were found to be significantly higher than in the patients without fracture. In conclusion, in the patients with EDH planned to be managed conservatively, skull fracture and additional intracranial lesions must not be thought as risk factors, on the contrary, resorption of the clot might be earlier than in the others.

Absorption↗
PubMed1997

The effect of condylectomy on extreme lateral transcondylar approach to the anterior foramen magnum.

The dorsolateral, suboccipital, transcondylar technique was used in this cadaveric study. The angle and distance measurements in the corridors were taken intradurally both superior and inferior of the foramen magnum level. In the first stage of this study, the findings which were gained from the standard lateral suboccipital approach were compared with the findings after condyle and lateral atlantal mass removal. After condylectomy, the approach to anterior foramen magnum via both corridors was found to be shorter and the lateral angle of the exposure of the anterior foramen magnum was found to be wider. The considerable shortening of the distances to the anterior foramen magnum, especially in the superior corridor, emphasises the necessity of combining standard approaches with condylectomy. In addition, it was found that after condylectomy, considerable widening of both transverse and longitudinal planes in the inferior corridor allows the surgeon greater access to work on lesions. Furthermore, the freed space between the superior corridor and the interior corridor, which was gained by condylectomy, shows that condylectomy provides a combined approach to the inferior and superior parts of the foramen magnum anteriorly.

Cadaver↗
PubMed1997

A case of ambiguous genitalia with unilateral amelia and unilateral peromelia of the upper limbs.

A 7-year-old patient is reported with a 46,XY karyotype, ambiguous genitalia and unilateral amelia and unilateral peromelia of the upper limbs. The external genitalia had essentially a female configuration with labia majora, large clitoris, and narrow vaginal opening. Gonadal tissue was not palpable on either side. The levels of 17-OH progesterone dehydroepiandrosterone sulfate (DHEA-S), androstenedione and luteinizing hormone (LH) were normal, but the level of follicle stimulating hormone (FSH) was elevated minimally. Abdominal ultrasonography (USG) was normal. On pelvic USG, neither uterus nor ovaries were seen. Genitography showed a blind vagina. Gonads, Müllerian and/or Wolffian structures were not observed at laparotomy. Clitoral recession and cut-back vaginoplasty were performed. The occurrence of these findings suggests embryonic testicular regression syndrome with bilateral transverse defect of the upper limbs. The case has been presented because the pattern of the birth defects, including both ambiguous genitalia and unilateral amelia on one side of the upper limbs and unilateral peromelia on the other, have not been described previously.

Abnormalities, Multiple↗
PubMed1995

Tumor status of lymph nodes in early endometrial cancer in relation to lymph node size.

A retrospective analysis of 36 patients with metastatic nodes out of 209 consecutively managed patients with a clinically stage I endometrial cancer was carried out. Of the 1023 lymph nodes removed, 154 nodes were found to be metastatic. The mean number of the involved nodes was 4.27 (range: 1-29). Of the 154 positive nodes, 3 had nodal diameters < or = 3 mm (1.9%), 84 had diameters of 4-10 mm (54.6%), 60 had diameters of 11-20 mm (39.0%) and 7 had diameters more than 20 mm (4.5%). With increasing lymph node size, the frequency of tumoral involvement varies from 1.0% in nodes < or = 3 mm to 63.6% in nodes bigger than 20 mm. In terms of patients, nine of them were found to have a single metastatic node ranging from 6 mm to 10 mm in diameter. In the remaining 27 patients with multiple metastatic nodes, the biggest nodes encountered were 6-10 mm in 4 (14.8%), 11-20 mm in 17 (62.9%) and more than 20 mm in 6 (22.2%) patients. Since mere sampling of the lymphatic tissue directed particularly to the enlarged nodes may not show the true incidence of positive nodes, a complete lymphadenectomy is advocated in order to obviate an understaging problem.

Endometrial Neoplasms↗
PubMed1995

Emergency postpartum hysterectomy.

Twenty-two deliveries were followed by emergency postpartum hysterectomy among 109,842 deliveries in the last 10 years, an incidence of 1 in 4992 deliveries (20/100,000). The leading causes of emergency postpartum hysterectomy were uterine rupture in 8 (36.3%), uterine atony in 7 (31.8%), and abnormally adherent placenta in 6 (27.3%) patients. Five of the uterine rupture cases followed previous cesarean births, whereas the other 3 followed dystocia. Of the 7 patients with uterine atony, 4 were after vaginal delivery and 3 were after cesarean birth. Of the 6 patients with adherent placenta, 4 had repeat cesarean deliveries and the other 2 were subjected to cesarean section for postterm pregnancies. The maternal mortality rate was found to be 4.5% (1/22). The perioperative morbidity included blood transfusion in 72.2%, febrile morbidity in 40.9%, and wound infection in 13.6% of the patients. Fetal mortality rate was 45.4%.

Endometrium↗
PubMed1994

Trends in maternal mortality at a university hospital in Turkey.

OBJECTIVE: To highlight recent trends in maternal mortality in Hacettepe University Hospital. METHOD: A retrospective clinical analysis of 117 maternal deaths between 1968 and 1992. RESULTS: The overall maternal mortality ratio was 180/100,000 (108/59,993). In terms of 5-year periods, the maternal mortality ratio declined from 417.7 in 1968-72 to 73.7 in 1988-92. Infection was the most common cause of death (59.8%), followed by cardiac disease (8.5%) and hemorrhage (8.5%). Infection related deaths were either due to septic abortion (75.7%) or puerperal sepsis (24.3%). While 73.9% of all deaths were due to infection in 1968-72, this figure contributed only 9.1% of the deaths in 1988-92. When infection, hemorrhage, cardiac disease ad toxemia are investigated together, percentages of their contribution varies from 95.7% in 1968-72 to 54.5% in 1988-92 period. CONCLUSIONS: Maternal mortality ratios are decreasing significantly in our institution. An another promising finding is the further reduction in direct causes especially in recent years. However, an improvement in the care of pregnant women is necessary to continue this declining trend.

Abortion, Septic↗
PubMed1994

Primary twin ovarian pregnancy.

A 20-year-old-woman, gravida II, para I, was admitted to the hospital with vaginal bleeding 17 weeks after her last menstrual period. Her pelvic examination was found to be compatible with 3.5 months of pregnancy by the attending physician. Ultrasonographic examination revealed an empty uterus and two dead fetuses with biometric data consistent with 14 weeks of pregnancy located in the left ovarian region. She was subjected to an explorative laparotomy and an intact gestational sac including the left ovary with normal tubes was observed; a unilateral salpingo-oophorectomy was carried out. Histologic studies confirmed a twin ovarian pregnancy. Although rare, ovarian pregnancy should be considered when approaching a case of ectopic pregnancy. Early diagnosis is generally based on ultrasonographic findings. Advanced cases with unruptured sac and multiple gestations may also be present.

Adult↗
PubMed1994

Is routine appendectomy beneficial in the management of ovarian cancer?

A retrospective analysis of 136 patients with ovarian carcinoma subjected to appendectomy as a part of surgical procedure was carried out to assess the importance of appendectomy in patients with ovarian cancer. Of the 136 patients studied, 94 had epithelial and 38 had non-epithelial type of primary ovarian carcinoma. In the remaining 4 patients, the primary operation was performed with an intraoperative diagnosis of ovarian carcinoma but the final pathological examination revealed appendiceal carcinoma metastatic to ovaries. The overall appendiceal involvement in the study group with primary ovarian cancer was found to be 32.5% (43/132). This figure was 15.7% and 39.3% for non-epithelial and epithelial tumors, respectively. Involvement of the appendix ranged from 8.8% for patients with stage I disease to 46.0% for patients with stage III-IV disease. Four of the appendices found to be inflamed during the surgical explorations were later reported as acute appendicitis. The frequent occurrence of metastatic disease in the appendix in patients with ovarian cancer suggests routine appendectomy is appropriate for staging early cases and for contributing to maximal cytoreduction in advanced cases.

Appendectomy↗
PubMed1994

Risk factors for recurrence in clinically early endometrial carcinoma: an analysis of 183 consecutive cases.

This study includes 183 patients with clinical stage I endometrial carcinoma. All patients had standard surgical staging procedure including peritoneal cytology, total abdominal hysterectomy, bilateral pelvic and paraaortic lymphadenectomy. The factors analysed for recurrence were age, menopausal state, cell type, grade, mitotic activity, myometrial invasion, lymphovascular space invasion, cervical involvement, microscopic vaginal metastases, adnexal metastases, peritoneal cytology, concomitant endometrial hyperplasia and pelvic and paraaortic node metastases. The overall recurrence rate was 14.2% (26/183). Of the 26 patients with recurrence, 11 had local and 13 had distant metastases. In the remaining two patients (7.7%), both local and pelvic metastases were observed. Of the factors analysed, age, grade, mitotic activity, myometrial invasion, lymphovascular space invasion, microscopic vaginal metastases, adnexal involvement and pelvic and paraaortic nodal metastases were found to be significant predictors of recurrence. After multivariate analysis, advanced age (RR = 1.05), marked mitotic activity (RR = 3.11), pelvic and/or paraaortic nodal metastases (RR = 6.37) were chosen as the most important determinants of recurrence. In terms of surgical pathological stages, recurrence risk reaches up to 45.4% for stage IIIC disease. Using surgical pathological parameters, it is possible to predict recurrence but because of high rate of distant failures it still seems hard to improve survival of this group. Detection of a substantial risk of recurrence even in stage IA/B grade 1 group warrants adjuvant therapy in all patients after primary surgery.

Age Factors↗
PubMed1994

Granulosa cell tumor of the ovary. A clinicopathological evaluation of 60 cases.

The patients with granulosa cell tumor of the ovary constituted 7.6% (60/780) of all ovarian malignancies treated at our Institution. The mean age of patients at diagnosis was 53.1. The most frequent symptom was abnormal vaginal bleeding. Of the 60 patients, 36 had stage I, 2 had stage II, 16 had stage III and 6 had stage IV disease. Endometrial hyperplasia and adenocarcinoma were detected in 18 and 3 patients, respectively. Lymph node metastasis was detected in only one of 18 patients subjected to lymphadenectomy. Recurrent disease was observed in 3 of 36 patients with stage I disease. The overall 5-year survival was found to be 85.0% (51/60). This figure varied from 100.0% to 63.6% according to the stage. In patients with stage I disease, surgery with and without adjuvant therapy achieved the same 5-year survival rate. In advanced stage, 5-year survival rate dropped from 90.0% with no gross residual disease to 25.0% with residual disease more than 2 cm. In patients with stage I disease, surgery only seems to be the treatment of choice. In advanced stage, since residual disease after surgery effects survival significantly, an aggressive surgical approach is advocated.

Adenocarcinoma↗
PubMed1993

Conservative management of epidural haematomas. Prospective study of 15 cases.

Conservative management of epidural haematoma (EDH) depends on a balance between expansion and resorption rate of the clot. 15 patients with EDH whose CT scans demonstrated a small EDH and were asymptomatic or with minor symptoms or with a delayed diagnosis were treated conservatively. The thickness of haematoma ranged between 4.9-40.8 mm. In two patients, the haematoma extended from the posterior fossa to the supratentorial region. In 7 patients, additional intracranial pathology was detected. None of the patients had neurological deterioration on follow up. The second CT was performed on second day at the earliest, in fourth week at the latest. We conclude that the patients with EDH who are neurologically stable during the first 24 hours after trauma, with small EDH and with minor or no symptoms or signs, might be candidates for conservative management. An absolute precondition for conservative management is close supervision of the patient.

Adolescent↗
PubMed1993

Experimental basilar artery spasm caused by autologous blood application: effects of clot removal and topical nicardipine.

In 24 albino New-Zealand rabbits spasm of the basilar artery was produced by local application of autologous blood. The effects of blood and blood clot removal or topical nicardipine, each alone and in combination of both methods, were studied and compared to untreated controls. As well clot removal alone as topical application of nicardipine without clot removal resulted in some, but statistically not significant, enlargement of the spastically narrowed basilar artery. Only the combination of both methods caused a significant vasodilatation, up to almost normal diameter range.

Animals↗