Kemal Bakir

The role of tissue reperfusion in the reexpansion injury of the lungs

OBJECTIVE The aim was to discuss the balance between free radical damage and body defense mechanisms that occurred in reexpansed pulmonary tissue and to evaluate the relationship between the changes in the pulmonary circulation and the mentioned balance. METHODS Twenty male Wistar Albino rats were used for these study results. Pneumothorax was created in the left hemithorax by percutaneous route in all the rats. After 7 days, the first group (n = 10) had a sternotomy under ketamine anesthesia. Following invasive measurement of pulmonary artery pressure, tissue samples were obtained from the lower lobes of the right and left lungs before reexpansion occurred. Tracheotomies were opened in the second group (n = 10) with a 16 gauge cannula. Following sternotomy, invasive mean pulmonary artery pressure measurements were obtained by the support of non-invasive cardiac monitorization. The lungs were aerated with 4 cmH(2)O oxygen and fixed volume support and 1 h of reexpansion was obtained. Invasive mean pulmonary artery pressure measurements were repeated after reexpansion and tissue samples were obtained from the lower lobes of left and right lungs. Nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) levels were measured in tissue samples, surfactant staining and light microscopic evaluations were performed. RESULTS At the end of the reexpansion, there was a decrease in mean pulmonary artery pressure (P < 0.01), MDA (P < 0.01) and SOD (P < 0.05) levels and an increase in NO (P < 0.05) levels. Under the light microscopic examination, in the samples that were provided with reexpansion, the alveolo-capillary membrane was thickened due to increasing edema, increase in the number of lymphocytes and return of the neutrophil leukocytes to the area. There was no significant difference between the groups in terms of surfactant staining. CONCLUSION The tissue reperfusion that is achieved with the restoration of blood flow during the reexpansion of collapsed lungs, can be the initial pathology in the chain of events that result in reexpansion injury.

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

Abstract 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.

Unilateral Testicular Torsion: Protective Effect of Verapamil on Contralateral Testicular Histology

In this experimental study, it was our aim to reduce the effects of ischemic insults to the contralateral testicle after unilateral testicular torsion. The protective effect of a calcium channel blocking agent (verapamil) on the histology and the tubular diameter of contralateral testicle was evaluated. Following a definite period of unilateral testicular torsion (i.e., 4 h), the protective effect of this specific medication was evaluated both after detorsion and orchiectomy procedures. The results of our study demonstrated the protective effect of verapamil on both parameters, especially in animals undergoing orchiectomy. The majority of the specimens demonstrated normal histologic findings together with preserved tubular structures after a 1-week period under verapamil medication.

Eosinophilic granuloma of the temporal bone.

Histiocytosis X or Langerhans cell histiocytosis (LCH) is a disease that possesses three less distinctive and overlapping states called eosinophilic granuloma (EG), Hand-Schuller-Christian (HSC) disease and Letterer-Siwe (LS) disease. EG is the least severe and localized form of all LCHs and possesses the best prognostic result. A high index of suspicion is required to diagnose the EG, especially when an ear disease is refractory to medical treatment. Early detection is important to manage the EG properly and to minimize the complications or sequels of treatment. Definitive diagnosis of histiocytosis is made by histopathological means and immunohistochemical detection of S-100 and CD1 antigens in the tissue samples. And differential diagnosis of the subgroups is made according to the clinical manifestations such as visceral organ or bone involvement. Surgical excision, radiotherapy and chemotherapy, either alone or in combination, are the main treatment options.

Primary pure ovarian choriocarcinoma mimicking ectopic pregnancy: a report of fulminant progression.

Nongestational choriocarcinoma of the ovary is a germ cell tumor with a worse prognosis than gestational choriocarcinoma. In this report we present a nongestational choriocarcinoma that was referred to our hospital as an ectopic pregnancy. The clinical features, management, and outcome are discussed.

Penile epithelioid sarcoma: MR imaging findings

Abstract. Magnetic resonance imaging findings of a 38-year-old man with epithelioid sarcoma of the penis is presented. It started as a firm, painless and slowly growing nodule at the base of his penis 6 months previously which caused pain radiating to the testis during coitus. It has been well known that sarcomas may well mimic reactive processes. Initial presentation of epithelioid sarcoma may provoke considerable diagnostic difficulty, and its differentiation from benign lesions, such as Peyronies disease and chronic inflammation, may be a clinical problem. In our present report the MR findings are compared with those of the epithelioid sarcomas of various locations reported in the literature and differential diagnosis of the entity is discussed. To our knowledge, this is the first report regarding the MR findings of the epithelioid sarcoma of penis.

The reliability of mediastinoscopic frozen sections in deciding on oncological surgery in bronchogenic carcinoma

IntroductionThis study was carried out to determine the accuracy of mediastinoscopic frozen section examination, performed prior to major surgery-especially where mediastinal lymph node metastasis (N2 disease) was suspected. We aimed to find out whether or not mediastinoscopic frozen section analysis was (i) a reliable tool when deciding to continue resection in lung cancer patients and (ii) reliable in diagnosing mediastinal masses.MethodsOne-hundred and thirty-six patients undergoing mediastinoscopy were enrolled in this study. Resection was planned for each case, and biopsies were taken from at least two sites, including the subcarinal lymph node. Thoracotomy and resection were performed when the results of frozen section examination were negative for malignancy in patients with lung cancer. Results of frozen section examination during mediastinoscopy were compared to the results of definitive histological examination of the same specimens stained using haematoxylin-eosin. Additionally, the results of frozen section examination were compared to the results of definitive histological examination of the lymph nodes excised during resection.ResultsWe determined total sensitivity, specificity, positive predictive and negative predictive values of 94.51%, 100%, 100% and 90%, respectively. In the 105 patients with malignant diseases, these values were 93.33%, 100%, 100% and 91.84%, respectively. In the 31 patients with benign diseases, values were 96.77%, 100%, 100% and 100%, respectively.ConclusionsIt was confirmed that mediastinoscopy supported by frozen section examination plays an important role in establishing diagnosis and planning treatment both in benign and malignant diseases.

Predictive value of renal histological changes for postoperative renal function improvement in children with congenital ureteropelvic junction stenosis

Background: The aim of this study was to evaluate the relationship between renal function, as measured by diuretic radionuclide renography, and the outcome of pyeloplasty. A study was designed to evaluate renal parenchymal biopsy specimens derived from children undergoing corrective surgery for ureteropelvic junction (UPJ) stenosis, and compare these to preoperative and postoperative renal function status.

Semiquantitative evaluation of testicular histology after testicular torsion : Protective effect of external cooling

To evaluate the protective effect of external cooling on testicular histology and tubular diameter, an experimental study was performed on rat testes that underwent a torsion procedure for a defined period of time (4 h). In a second group of animals external cooling for 90 min was performed during the torsion procedure. Evaluation of both the semiquantitative testicular histology and tubular diameter demonstrated a relatively well-preserved histology and tubular diameter. However, significant changes were noted in testes that underwent the torsion procedure without any protective measure. Our results indicate the protective effects of hypothermia in ischemic testes undergoing torsion with regard to both histologic and tubular alterations.

Is D2-40 a useful marker for distinguishing malignant mesothelioma from pulmonary adenocarcinoma and benign mesothelial proliferations?

Since pulmonary adenocarcinomas, malignant mesotheliomas (MM), and sometimes benign mesothelial proliferations show a great histomorphological resemblance to each other, an immunohistochemical panel is usually necessary for differential diagnosis. D2-40 is an available monoclonal antibody, which is already in use as a lymphatic endothelial marker. It has also been suggested to be useful in identifying the mesothelial differentiation. The aim of this study is to compare D2-40 immunostaining in MM, pulmonary adenocarcinoma, and benign mesothelial proliferations. In this retrospective study, D2-40 immunostaining was investigated in 37 cases of MM, 36 cases of pulmonary adenocarcinoma, and 31 cases of benign mesothelial proliferation. The diagnosis of MM had previously been confirmed by a panel including calretinin, CK5/6, and CEA. Predominantly membranous immunoreactivity was observed in 51% of MMs and in 55% of benign mesothelial proliferations. All the 36 pulmonary adenocarcinomas were negative. These results were statistically significant (p<0.001). We believe that D2-40 may be helpful in the differential diagnosis of MM from pleural involvement of pulmonary adenocarcinoma.