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A Poyraz

Publications and source records attributed to A Poyraz.

14 recordsLinked to original sources
PubMed2001

Expression of Bcl-2 and c-ErbB-2 in colorectal neoplasia.

Several studies have been demonstrated the value of c-ErbB-2 and Bcl-2 in predicting the biological behaviour of tumors. The aim of this study was to investigate Bcl-2 and c-ErbB-2 expression in colorectal carcinomas and the correlation between their presence and other clinicopathologic parameters. Eighty-six colorectal carcinomas and 17 adenomas were stained with Bcl-2 and c-ErbB-2 immunohistochemically. Staining patterns were assessed semi-quantitatively and correlated with tumor size, Duke s classification, tumor differentiation, mucinous characteristic and anatomic locations. We detected Bcl-2 expression in 10 of 17 adenomas (58.8 %) and 31 of 86 carcinomas (36.04 %). Positive staining in normal mucosa was observed only in the compartment of cryptic cells. However neither the difference in the rates of Bcl-2 positivity in adenoma and carcinoma groups, nor the correlation with other mentioned clinicopathological parameters, were found statistically significant. Bcl-2 expression was found to be significantly high in mucinous carcinomas. Expression of c-ErbB-2 was observed in 12 of 86 (13.95 %) carcinomas. It was not detected in adenomas and normal mucosa. Although the incidence of c-ErbB-2 in nonmucinous carcinoma was higher than that of mucinous carcinoma, this was not significant. In addition we were unable to show any significant relation between c-ErbB-2 expression and other clinicopathologic features. Our result suggest that c-ErbB-2 protein expression in colorectal carcinomas, is not very frequent event. There is no correlation between c-ErbB-2 expression and malignant potential of colorectal carcinomas. Higher expressions of Bcl-2 in adenomas than carcinomas suggest us a possible role of Bcl-2 in early carcinogenesis of colon. However since we were unable to find any significant correlation between Bcl-2 expression and other parameters the impact of this gene on biological behavior is still unclear for us.

Adenoma↗
PubMed2001

Investigation of the ototoxic effects of interferon alpha2A on the mouse cochlea.

This prospective randomized study investigates the possible toxic effects of interferon (IFN) alpha2A on the mouse cochlea. Thirty-six albino Swiss mice that were randomly assigned to 3 groups underwent baseline auditory brain stem response testing bilaterally to objectively assess baseline hearing levels. The first group received a single dose of 50,000 units, and the second group received 100,000 units of IFN-alpha2A intraperitoneally, whereas the third group was given no medication. Repeat auditory brain stem response testing revealed a significant rise in mean baseline peak equivalent sound pressure level thresholds in the groups that received IFN (P < 0.001). Histologically, the cochleae of mice that received IFN had a decreased number of fibroblasts in the spiral limbus, as well as prominent cytoplasmic vacuolation of these cells, compared with control animals. Loss of hair cells was not observed. It is possible that reversible biochemical and metabolic changes in the cochlea, rather than morphologic abnormalities, manifest IFN ototoxicity.

Animals↗
PubMed2001

Multiple hemangiomas of the foot: a case report.

Although hemangiomas are common soft tissue tumors, it rarely involves the feet. We are reporting a forty-seven-year-old female with multiple hemangiomas of her left foot without pain. During surgery there were seven well-defined masses that were totally excised after ligation of penetrating vessels. The microscopic investigation revealed mixed-type (capillary and cavernous) hemangioma. We had not experienced any recurrence after two years follow up period.

Female↗
PubMed2001

Using imprint and frozen sections in determining the surgical strategies for thyroid pathologies.

OBJECTIVE: To compare the diagnosis of thyroid pathological findings by using frozen section and preoperative imprint. METHODS: From January 1998 to December 1999, one hundred and three consecutive patients admitted to Department of Surgery, Gazi University Medical Faculty for thyroid operation, were prospectively included into the study. In all patients, imprint and frozen section were carried out from their suspected nodules and the results were compared with the permanent biopsy. Those findings used to find out sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of frozen section and imprint. Because of the definitive differentiation of malignant or benign lesions could not be done, three patient were excluded from the study. RESULTS: In our study; sensitivity, specificity, PPV, NPV and accuracy for imprints was found as 83.3%, 97.7%, 83.3%, 97.7% and 96% (respectively), while respective corresponding data for frozen section were 81.8%, 96.6%, 75%, 97.7% and 95%. In one patient, the pathological finding of follicular carcinoma as found by permanent section was accurately diagnosed by imprint, but missed by frozen section. Both the imprint and frozen section failed to diagnose two papillary carcinoma. Overall cancer rate among 103 patients was 12 % (nine papillary carcinoma, one Hürthle cell carcinoma and two follicular carcinoma). CONCLUSION: Both the frozen sections and imprints showed high sensitivity rate and similar accuracy rates. So, if there is no opportunity for frozen section, the imprints could be used. Furthermore, the use of imprints is less time consuming and less expensive than that of frozen sections.

Adult↗
PubMed2000

Submandibular accessory salivary gland causing Warthin's duct obstruction.

BACKGROUND: Submandibular masses are mostly secondary to sialolithiasis. Salivary gland tumors should be considered in the differential diagnosis. In this case report, an unusual cause of Warthin's duct obstruction caused by an accessory salivary gland tissue is presented. METHODS: Sialography revealed the submandibular accessory salivary gland. RESULTS: Submandibular gland excision was performed and histopathologic investigation showed the accessory salivary tissue, which was narrowing the Warthin's duct. CONCLUSIONS: In cases of a symptomatic submandibular accessory gland, excision extirpation of the submandibular gland and accessory salivary tissue should be undertaken.

Adult↗
PubMed2000

Huerthle cell neoplasms of the thyroid: predicting malignant potential.

OBJECTIVE: Assessment of malignancy criteria in Huerthle cell neoplasm. METHODS: This study intends to review retrospectively the patients who were operated for Huerthle cell neoplasia at Gazi University, Department of General Surgery between January 1986 and October 1999. Pathological specimens from 63 patients (20 males and 43 females) were investigated in this study, 48 of which revealed Huerthle cell adenoma and 15 revealed Huerthle cell carcinoma. The mean age of the patients with Huerthle cell adenoma was 40.7+/-1.59 yr while it was 51.3+/-1.83 yr in patients with Huerthle cell carcinoma. Mann-Whitney U and Chi-square tests were used for statistical analysis. RESULTS: . Fifty-two of the 63 patients had fine needle aspiration (FNA) biopsy prior to operation, 49 of those were reported to have suspected Huerthle cell neoplasia (HCN) and three had suspected Huerthle cell carcinoma (HCC). The sensitivity of FNA for HCN was 20 %, specificity was 100 %, positive predictive value was 100 % and negative predictive value was 76 %. For all patients, peroperative frozen section (FS) biopsy was examined. Fifty-nine of the FS specimens revealed HCN and four revealed HCC. The sensitivity, specificity, positive predictive value and negative predictive value of FS biopsy were 27 %, 79 %, 28.5 % and 77.5 %, respectively. In this retrospective study, there was a statistically significant correlation between malignancy and the size of the tumor (P<0.05) according to Chi-square test, and also a statistically significant correlation between malignancy and the age of the patient (P<0.05) according to Mann-Whitney U test. CONCLUSIONS: In cases where FS and FNA biopsies cannot adequately define the benign or malignant behaviour of the tumor, the age of the patient and the diameter of the tumor must be taken into consideration for accurate surgical strategy. Particularly for 50 year-old and elderly, incidence of malignancy is statistically significant without considering sex of the patient.

Adenocarcinoma↗
PubMed1999

Hematopoietic stem cell transplantation from non-replicative hepatitis B virus carriers is safe.

BACKGROUND/AIMS: Hepatitis B virus can cause serious problems in individuals undergoing organ transplantation. The aim of this study was to evaluate the hepatic events among HBs-Ag positive recipients and HBs-Ag negative recipients who received products from hepatitis B virus carriers. METHODS: A total of 151 patients received an allogeneic hematopoietic stem cell transplantation at the Department of Hematology-Oncology, University of Ankara, between June 1989 and June 1998. Among these, eight HBs-Ag positive and four HBs-Ag negative recipients received a product from a hepatitis B virus positive donor. The median follow-up period for these 12 patients was 13.2 months. RESULTS: Three of the eight HBs-Ag positive recipients died (one from hepatic failure); of the remainder, two are HBs-Ag negative, two HBs-Ag positive with normal liver injury tests and one HBs-Ag positive with elevated ALT levels. Of the four HBs-Ag negative recipients who received stem cells from a hepatitis B positive donor, two died; none of the patients in this group became HBs-Ag positive after transplantation. CONCLUSION: Hepatitis B virus infection is a common problem in patients being considered for allogeneic hematopoetic stem cell transplantation, especially in areas where hepatitis B virus infection is endemic. We believe that the presence of HBs-Ag positivity is not an absolute contraindication for allogeneic hematopoetic stem cell transplantation unless the hepatitis B virus is in a replication phase.

Adolescent↗
PubMed1999

P53 and proliferating cell nuclear antigen (PCNA) expression in non-tumoral liver diseases.

The tumor suppressor gene p53 is known to be involved in the negative regulation of cell growth. Proliferating cell nuclear antigen (PCNA), which is a nuclear protein and a component of the DNA replication process, is also involved in growth regulation. Both have been studied as progression markers in various tumors including hepatocellular carcinoma. In the present study, the aberrant p53 protein and PCNA expressions in non-tumoral liver diseases were investigated. Using monoclonal antibodies anti-p53 (D07-DAKO) and anti-PCNA (PC10-DAKO), 149 samples were stained, including 10 normal and 10 tumoral control liver tissues. p53 Overexpression was detected in 52 specimens (35%) whereas PCNA positivity was found in 96 (64%). There were 21 different pathological entities but most of the positive samples could be grouped into four types of diseases; namely, non-specific reactive hepatitis, steatohepatitis, chronic hepatitis and cirrhosis. Statistical analyses performed on these groups revealed that p53 positivity was found to be significantly higher in steatohepatitis (P < 0.05), while PCNA positivity did not show any statistical significance. The number of samples showing both p53 and PCNA positivity was 42 but their coexistence was not found to be significant. Certain cytological alterations like nuclear pleomorphism, steatosis and cholestasis, in addition to necroinflammatory activity, were evaluated for their possible impact on p53 and/or PCNA positivity. Necroinflammatory activity in steatohepatitis and steatosis in chronic hepatitis was found to be significant for p53 positivity (P < 0.05). In contrast, nuclear pleomorphism in non-specific reactive hepatitis was found to be significant for PCNA positivity (P < 0.05).

Cell Nucleus↗
PubMed1999

Expression of c-erbB-2 oncoprotein in gastric carcinoma: correlation with histopathologic characteristics and analysis of Ki-67.

Amplification and overexpression of the c-erbB-2 gene has been demonstrated in several tumors and thought to be important determinants of biologic behaviors of carcinomas. In this study, correlation between c-erbB-2 expression und histopathologic parameters, including proliferative activity of gastric carcinomas was evaluated. Paraffin-embedded tissue sections from 62 patients who underwent curative resection of gastric carcinoma were analyzed immunohistochemically for the expression of c-erbB-2 and Ki-67. Strong membrane staining for c-erbB-2 was detected in 11 of 62 gastric carcinomas (17,7%) and no positive reaction was evident in noncancerous tissue. The incidence of c-erbB-2 positivity in intestinal type carcinomas (24,3%) was higher than that of diffuse type carcinomas (4,76%). Positive staining for c-erbB-2 was present in one of the 9 (11,1%) early gastric carcinomas and 10 of 53 (18, 8%) advanced gastric carcinomas. However, no statistically significant relationships were found between c-erbB-2 expression and histopathologic type, depth on invasion, the tumor size or lymph node metastases. Among the metastatic lymph nodes, 3 were positively stained with c-erbB-2 whereas the primary tumors of two cases had been found to be negative. Additionally, no correlation was found between c-erbB-2 reactivity and proliferative activity of carcinoma cells. The results suggest that expression of c-erbB-2 protein may occur selectively in intestinal type of gastric carcinomas. However, c-erbB-2 expression is not a reliable marker of malignant potential in gastric carcinomas.

Humans↗
PubMed1999

Preoperative fine-needle aspiration cytology versus frozen section in thyroid surgery.

OBJECTIVE: In a double blind prospective clinical study to evaluate the diagnostic potential of peroperative fine needle aspiration cytology as compared to peroperative frozen section in thyroid surgery. METHODS: The diagnostic value of one hundred consecutive preoperative (FNA) and peroperative fine needle aspiration (p-FNA), frozen section (FS) and permanent section (PS) examination for thyroid nodules were studied prospectively in order to assess and compare the accuracy, sensitivity and specificity. RESULTS: Out of 100 patients PS showed 11 % of malignancies, while p-FNA showed 5 % and FS showed 6% of malignant cases with no false positive, but with 6 and 5 false negative results, respectively. Thus, as compared with FS, one false negative finding was obtained by p-FNA in a case of malignant tumor which could be definitely ascertained by frozen section technique. However, concerning the benign nodules no differences were found between p-FNA and FS. CONCLUSIONS: Peroperative fine needle aspiration seems to be a useful method which can be properly performed because the nodule can be easily seen during the surgical procedure. However, further clinical observations of large numbers of patients are needed.

Adult↗
PubMed1999

The effect of EGb 761 on the doxorubicin cardiomyopathy.

Doxorubicin (Dx) is used to treat a number of types of cancer. The drug produces many toxic reactions and cardiomyopathy. Many drugs have been used to prevent this myocardial damage caused by peroxidative alterations. EGb 761 is being used to prevent arrhythmias in ischemic myocardium. We decided to establish the tissue protective effect of EGb 761 against myocardial toxic effects of Dx in three groups of rats. Cardiotoxicity signs of Dx were found to be dose-related, beginning at 30 mg/kg dose and being apparent at 45 mg/kg dose. 48 hr after a single i.v. injection, myocardial tissues showed a marked edema, vacuolization and fragmentation. We compared the changes in heart tissue biochemically and histopathologically among the control, Dx treated and EGb 761 (100 mg/kg/d.x 4, i.p.) + Dx treated groups. Biochemical results of CK-MB and MDA values showed a significant decrease in Dx + EGb 761 group when compared with Dx treated group. Histopathologically, myocardial tissues of Dx + EGb 761 treated group were found to have diminished vacuolization and fragmentation. These results suggest that EGb 761 might have the same therapeutic potential in Dx related cardiomyopathy.

Animals↗
PubMed1998

Accuracy and Significance of Fine-Needle Aspiration Cytology and Frozen Section in Thyroid Surgery.

OBJECTIVE: In the retrospective study to review the records of patients who had undergone thyroid surgery between 1986-1995 and to determine the need of frozen section (FS) following FNA biopsy. METHODS: The records of 2083 patients who had thyroid surgery in Gazi University Medical Faculty Department of General Surgery between 1986-1995 were retrospectively reviewed to determine and compare the accuracy and significance of fine-needle aspiration (FNA) cytology and intraoperative frozen section (FS). Results. In 61 patients, both FNA and FS diagnosis were available for the comparison with the final pathologic diagnosis. In 196 patients, FNA diagnosis was available for the comparison with the final pathological diagnosis by permanent section and in 377 patients FS diagnosis was available for the comparison with the final pathological diagnosis. The sensitivity value for detection of malignancy by means of FNA was 57.1 % compared to 82.2 % by means of FS, and FS diagnosis was more specific (99 %) than FNA diagnosis (90.9 %). FNA diagnosis of benign conditions was correct in 141 of 150 (94 %) patients. FS diagnosis of benign conditions was correct in 313 of 321 (97.5 %) patients. Nine patients had the FNA findings that were positive for malignancy and FS confirmed this diagnosis in 8 patients. Conclusions. FNA is an important diagnostic tool for eliminating benign nodules, but it is not perfect. FS is very important for determining the surgical procedure, and because of direct observation of suspicious nodule, it is even more accurate. Using these tools together is more reliable, since the number of false positive and false negative values is lower than if only the individuals methods are used.

Journal Article↗
PubMedDate not supplied

Bcl-2 and LMP1 expression in nasopharyngeal carcinomas.

In vitro studies of B-cells immortalized by Epstein-Barr Virus (EBV) have shown that B-cell leukemia/lymphoma-2 (bcl-2) protein expression is upregulated by the EBV-latency-associated antigen, latent membrane protein 1 (LMP1). The same phenomenon has also been observed in epithelial cells in vitro. However, such correlation between these 2 markers has not been shown in nasopharyngeal carcinoma (NPC), in which EBV infection is a well-known etiologic factor. This retrospective study examined 35 cases of undifferentiated NPC to answer the question of whether LMP1 and/or bcl-2 presence can be used as biomarkers at treatment response, as well as to see the relationship between bcl-2 and LMP in NPC. Of the 35 patients, 26 (74.3%) were bcl-2, and 10 (28.6%) were LMP1-positive. Although a significant correlation was observed between bcl-2 and LMP1 staining (P =.003), it appeared that bcl-2 expression could be independent of LMP1. Statistical analysis showed that cervical lymph node metastasis (P =.04) and cranial nerve involvement (P =.03) are the only variables that significantly affect patient survival. At this time, bcl-2 and LMP1 presence are not significant indicators of outcome; however, although they are not directly related to survival, expression of both bcl-2 and LMP1 was strongly correlated with cervical lymph node metastasis, which is a potent predictor of patient survival.

Adaptor Proteins, Signal Transducing↗