Biomedical subjects

R Uçak

Publications and source records attributed to R Uçak.

10 recordsLinked to original sources

PubMed2002

The inhibition of pro-inflammatory cytokines with pentoxifylline in the cardiopulmunary bypass lung.

In addition to preventing tissue energy loss during cardiopulmonary bypass, pentoxifylline (Ptx) prevents the production of pro-inflammatory cytokines as well. The aim of this study was to investigate whether Ptx decreases the inflammatory effects of cardiopulmonary bypass on the lungs during open-heart surgery. The patients in the study group (n = 15) who were going through an open-heart surgery had 500 mg l(-1) of Ptx added to their prime solution, whereas the patients in the control group (n = 10) only received prime solution. Pre-pump and post-pump blood samples were obtained from both groups and assayed for interleukin-6 (IL-6), interleukin-8 (IL-8) and tumour necrosis factor alpha (TNFalpha). Lung tissue samples that were obtained after the pump were examined with light microscopy and stained for tissueTNFalpha. Non-parametric Wilcoxon test was utilized for statistical evaluation. In the post-pump period, the difference in the IL-6, IL-8 and TNFalpha levels of the two groups was found to be statistically significant (P<0.005). The tissue samples from the control group had significant staining with TNFalpha. We think that Ptx has important protective effects on the lungs during cardiopulmonary bypass.

Adult↗

PubMed2002

Prognostic factors and c-erbB-2 expression in non-small-cell lung carcinoma (c-erbB-2 in non-small cell lung carcinoma).

The human proto-oncogene c-erbB-2/neu gene, which is structurally similar to the epidermal growth factor receptor gene, encodes a transmembrane protein of 185 kDa (p185) with tyrosine kinase activity. Paraffin-embedded sections from 42 cases with lung carcinoma were stained immunohistochemically using the Avidin-Biotin Horseradish Peroxidase method to search for c-erbB-2 reaction. Results were evaluated semiquantitatively. The c-erbB-2 expression from each case was compared according to tumor type, grade, mitotic activity, clinical stage and lymph node metastasis. Results were statistically analyzed by using chi-square tests. We were unable to detect a significant relation between c-erbB-2 expression and histological grade, nodal metastasis, number of mitotic figures or tumor type, but we did observe a statistically significant correlation between clinical stage and increased c-erbB-2 expression (p < 0.05). In our opinion, c-erbB-2 expression in human lung carcinomas may be useful for determining clinical outcome.

Carcinoma, Non-Small-Cell Lung↗

PubMed2001

Renal tubular injury induced by hyperoxaluria: evaluation of apoptotic changes.

In order to evaluate the injurious effect of hyperoxaluria on renal tubular epithelium, as judged by apoptotic changes in the renal parenchyma, we performed an experimental study in 20 rabbits. In the experimental group animals (n = 10) severe hyperoxaluria was induced by continuous ethylene glycol (EG; 0.75%). Histologic alterations, including crystal formation, together with apoptotic changes were evaluated after 7 and 28 days. Control group animals (n = 10) received normal distilled drinking water. Following 7- and 28-day periods, tissue sections obtained from kidneys were examined histopathologically under light microscopy for the presence and the degree of crystal deposition in the tubular lumen. Apoptotic changes in renal tubular cells were examined using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick and labeling (TUNEL) method during the same follow-up period. Crystal deposition was evident in the tubular lumen of tissue sections obtained during the 7-day examination period. During the 28-day examination period, however, these findings were found to be either limited or to have disappeared. In relation to apoptotic changes, the percentage of positive nuclei stained using the TUNEL method was from 11 to 20% in the experimental group and 5.6% in the control group. Our findings indicate that both calcium oxalate (CaOx) crystals and hyperoxaluria itself may be injurious to renal tubular cells, as indicated by apoptotic changes. These changes may be responsible for the pathologic course of urolithiasis.

Animals↗

PubMed2001

AgNOR/P53 expression compared with different grades in bladder carcinoma.

OBJECTIVE: The aim of this study is to assess the relation between silver-strained nucleolar organizer regions (AgNOR)/P53 expression and urothelial neoplasm of the bladder which graded according to the WHO/ISUP tumor grading system. METHODS: Transurethral resection materials (TUR) and cystectomy specimens from 52 patients with bladder urothelial carcinomas were stained by AgNORs and analyzed immunohistochemically using an avidinbiotin peroxidase method for p53 staining and also silver for AgNORs. RESULTS: Nuclear p53 accumulation was determined in two of 5 LMP cases (%40), in 10 of 22 LGC (%45.4), and in 8 of 25 HGC (%32). Positivity of p53 accumulation was observed in 20 (%57.7) of all cases. There was no statistically significant relationship between AgNOR score of p53(+) and p53(-) cases. There was no correlation between LGC and LMP, also between LGC and HGC (p > 0.05), but a meaningful relationship was found between LMP and HGC (p = 0.03). Association between P53 and grade, AgNOR value and grade, p53 and AgNOR was found statistically insignificant. CONCLUSIONS: Although we found a statistically significant correlation between AgNOR count of LMP and HGC, this study did not show a satisfying correlation between AgNOR, p53 and any grade of urothelial carcinoma.

Carcinoma, Transitional Cell↗

PubMed2001

Cycline-dependent kinase inhibitor, p27 (KIP1), is associated with cholesteatoma.

OBJECTIVE: Cyclin-dependent kinases (CDKis) can arrest the cell cycle, which in turn inhibits the cell proliferation. P27 (KIP1) is a CDKi and acts as a tumor suppressor gene. In this study, we aimed to investigate the role of p27 CDKi in cholesteatoma, a disease characterized by the presence of hyperproliferative squamous epithelium. STUDY DESIGN: Immunohistochemical staining of 15 cholesteatoma and 18 control ear canal skin samples, which were taken intraoperatively, was performed for p27 positivity. METHODS: The monoclonal antibodies to p27 were used for immunohistochemical staining of the sections. The streptavidin-biotin horseradish method was used. The number of cells staining positive for p27 was calculated, and the intensity of p27 positivity was graded. RESULTS: P27 positivity was obtained in 9 (50%) of 18 skin tissues. In the cholesteatoma tissues, p27 positivity was found only in 2 (13.3%) tissue samples. The difference between the groups were statistically significant (P =.03). The mean numbers of p27 positivity were 11.8 +/- 15.5 and 1.4 +/- 3.8 (mean +/- standard deviation) in the skin and cholesteatoma samples, respectively. This difference was also statistically significant (P =.02). The p27 results of primary and secondary cholesteatoma samples were not significantly different (P =.3). The results of p27 were not related to the gender of the patients (P =.8). CONCLUSION: P27 is involved directly or indirectly in the occurrence of cholesteatoma. Alterations of p27 levels in keratinocytes can influence the proliferative state of the keratinocytes. Altered p27 levels in cholesteatoma may suggest a molecular pathology in cholesteatoma. The search for significance of CDKis seems promising to better understand the pathogenesis of cholesteatoma.

Cell Cycle Proteins↗

PubMed2001

Unilateral testicular torsion: evaluation of bcl-2, p-53 and PCNA expression in contralateral testes.

OBJECTIVES AND METHODS: The present study aims to evaluate the histologic as well as apoptotic changes indicated by PCNA, p-53 and bcl-2 expression in the contralateral testes after a period of unilateral testicular torsion of 4 h. RESULTS: Regarding the histologic changes, while some significant alterations such as complete or incomplete spermatocytic arrest as well as sertoli cell only formation have to some extent been noted after the detorsion procedure, reasonably better preserved histology could be demonstrated following the orchiectomy procedure both in the early and late follow-up. Thus, the orchiectomy procedure was found to be limiting enough on the severity of the histologic changes in the contralateral testes after a certain period of time following the torsion procedure. On the other hand, however, in relation to the apoptotic events indicated by the three markers, while PCNA activity was found to be significantly different depending on the procedure performed (detorsion or orchiectomy), p-53 and bcl-2 positivity did not exhibit any difference in this aspect. Increased PCNA activity (especially after the detorsion procedure) together with marked positivity of p-53 both in the early and late follow-up indicated the increased cell turnover in the contralateral testes, which in turn may be accepted as a sign of increased apoptosis in these testes. In addition to these findings, bcl-2 expression has been found to be consistently negative in all specimens evaluated both in the early and late follow-up. CONCLUSION: Taking into account the strong inhibitory effect of bcl-2 during apoptotic events, these findings again support the likelihood of increased apoptosis in the contralateral testes.

Animals↗

PubMed2001

Malignant mixed tumor of the larynx: a case report.

Malignant mixed tumour (MMT), which is a salivary gland tumour, is the malignant form of pleomorphic adenoma. Although the tumour can also originate from the minor salivary glands throughout the submucosa in the head and neck region, laryngeal involvement is quite rare. An additional case of laryngeal MMT presented in a forty-five year old man, and the diagnostic, immunohistochemical (S-100, actin, vimentin, epithelial membrane antigen) and therapeutic procedures were presented.

Humans↗

PubMed2000

Inflammatory pseudotumor of the lung.

Inflammatory pseudotumors of the lung are uncommon in the thoracic surgical literature. These masses resemble carcinoma of the lung radiographically and are discovered only at time the of histologic review of the resected specimen. We report a case of inflammatory pseudotumor that was excised without pulmonary resection, although it completely filled the right hemithorax. We think it was the greatest inflammatory pseudotumor in the English literature.

Biopsy↗

PubMed2000

Significance of Fas protein in squamous cell carcinoma of the larynx.

The purpose was to elucidate the clinical significance of Fas protein in laryngeal squamous cell carcinoma (LSSC). Medical records of 30 patients who were operated for LSCC between 1991 and 1997 were reviewed, and histopathological and immunohistochemical studies of the archival tumor tissues were performed. Conventional histopathology included tumor grading, mitotic counting (MC) and status of the cervical lymph nodes. The monoclonal antibodies to Fas (DAKO M 3554) and nm23 (DAKO A0096 Lot 035) proteins were used for immunohistochemical staining. Streptavidin-Biotin, horseradish method was used. Positive staining for both Fas and nm23 was obtained in 27 (90%) tumor samples. There was no correlation between neck metastasis and Fas positivity (r = 0.126, p = 0.505 and chi2 = 0.062, p = 0.996, respectively). Fas positivity did not correlate to grade (r = 0.282, p = 0.130), tumor size or T (r = 0.0457, p = 0.810, chi2 = 0.0.018, p = 0.999) or laryngeal site of involvement (chi2 = 0.0937, p = 0.992). However, a correlation was found between Fas and MC (r = 0.482. p = 0.007). There was also a correlation between Fas and nm23 positivity (r = 0.614, p < 0.0001). Fas protein expression has no prognostic value in LSCC, because the Fas values do not correlate with grade, stage or nodal status of neck. However, 90% of LSCCs expressed Fas protein. Understanding the functional status of the Fas receptor proteins may lead to development of new therapeutic options for LSSC in the future.

Aged↗

PubMed1996

Sister chromatid exchange frequency in inhabitants exposed to asbestos in Turkey.

Pleural mesothelioma, lung cancer, pleural calcification and fibrosis have been observed among inhabitants of the villages in Ivriz-Zanapa valley in Turkey. Earlier reports have stated that these endemic pathological conditions are caused by the inhalation of actinolite asbestos, a mineral commonly used indiscriminately to paint the walls and floors of houses. In the present study, 40 inhabitants in Yassikaya village in Ivriz-Zanapa valley and 20 controls were further investigated. The peripheral blood lymphocytes were cultured and harvested at 72 h for sister chromatid exchange (SCE) frequency. Inhabitants had a raised mean SCE rate compared with a control population.

Adult↗