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Metin Karakok

Publications and source records attributed to Metin Karakok.

11 recordsLinked to original sources
PubMed2005

Rapidly advancing invasive endomyocardial aspergillosis.

The exposure to Aspergillus organisms/spores is likely common, but disease caused by tissue invasion with these fungi is uncommon and occurs primarily in the setting of immunosuppression. We report a case of rapidly advancing invasive endomyocardial aspergillosis secondary to prolonged usage of multiple broad-spectrum antibiotics in a nonimmunocompromised host. A 36-year-old cotton textile worker presented to our institution with a 3-month history of weight loss and fatigue. He reported receiving prolonged use of multiple broad-spectrum antibiotic treatment. The echocardiogram demonstrated multiple endomyocardial vegetations and a mass in the left atrium. Myocardial biopsy specimen revealed an invasive endomyocardial aspergillosis. The patient was investigated for immune deficiency including HIV, and this workup was negative. Treatment was started with amphotericin B and heparin for presumed left atrial thrombus. The patient died because of a rupture of mycotic aneurysm that resulted in cerebral hemorrhage. This case illustrates the risk of an invasive fungal infection in a nonimmunocompromised host who is a prolonged user of antibiotics in the setting of environmental exposure of opportunistic invasive fungal infections.

Adult↗
PubMed2004

Extensive inflammatory nevus comedonicus involving half of the body.

Nevus comedonicus is an uncommon variant of adnexal hamartoma without known cause. It usually occurs on the face, neck and chest and appears as groups of closely arranged dilated follicular openings with keratin plugs. We report extensive inflammatory nevus comedonicus in a 14-year-old boy involving half of his body, limited by the midline, with suppuration and residual scarring. The lesions first appeared at 3 years of age and worsened at the start of puberty. The clinical features, etiopathology, histopathology and treatment options of nevus comedonicus are briefly reviewed in the light of the literature.

Adolescent↗
PubMed2004

Cyclo-oxygenase 2 expression in laryngeal squamous cell carcinoma and its clinical correlates.

OBJECTIVE: To assess the significance of cyclo-oxygenase 2 (COX-2) in laryngeal squamous cell carcinoma (LSCC). STUDY DESIGN: An immunohistochemical study in which 39 patients with LSCC were included. METHODS: Immunohistochemical staining of the paraffin-embedded tumour tissues was performed using isoform-specific COX-2 polyclonal antisera (Santa Cruz, Calif., USA). COX-2 results were compared with the clinical parameters of the patients. RESULTS: COX-2 was detected in all tumour tissues. In the normal laryngeal tissue around the tumour area, which served as control, there was no COX-2 staining. There was no relationship between the COX-2 results and the location of the primary tumour, T stage and N stage, survival, recurrence or pulmonary metastases. CONCLUSION: The absence of a relation between COX-2 positivity and clinical parameters may suggest an involvement of COX-2 in laryngeal carcinogenesis. Since COX-2 positivity could be detected in all LSCC specimens studied, COX-2 could serve as a therapeutic target in LSCC.

Carcinoma, Squamous Cell↗
PubMed2004

Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis.

Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH.

Adult↗
PubMed2003

Facial linear focal elastosis: a case report.

BACKGROUND: Linear focal elastosis is an uncommon disorder that clinically shows band-like stria and a histological focal increase in elastic fibers. The disorder preferentially affects men after the age of 60 years and occurs on the lower back. The pathogenesis of linear focal elastosis is still somewhat of an enigma. METHOD: A 50-year-old farmer presented with an unusual linear lesion on the left side of his chin. The patient was frequently exposed to sun because of fieldwork for a period of more than 40 years. RESULTS: Skin biopsy specimen revealed a massive abnormal collagen deposition extending from the subpapillary dermis to the lower dermis with numerous wavy bundles of fibers. Elastin van Gieson stain for elastic fibers showed that abnormal elastic fibers were increased within a massive abnormal collagen deposition. Diagnosis of facial linear focal elastosis was made after clinicopathological correlation. CONCLUSION: Facial involvement of linear focal elastosis has not been reported previously in the literature. It has been suggested that sunlight has a minor role in the development of elastotic change in linear focal elastosis. However, our patient was a farmer and was exposed to sunlight frequently for a period of more than 40 years, suggesting that ultraviolet radiation may play a role in the pathogenesis of linear focal elastosis.

Centella↗
PubMed2003

Evaluation of heat shock protein 70 expression in renal parenchyma subjected to shockwave lithotripsy.

PURPOSE: In this experimental study in a rabbit model, renal parenchymal heat shock protein 70 (hsp70) levels were assessed in an attempt to evaluate the traumatic effects of high-energy shockwaves (HESW), which have been found to induce transient ischemia during the procedure. MATERIALS AND METHODS: Eighteen white New Zealand rabbits, each weighing 3 to 5 kg, were included in the study. The animals were divided into three groups, and various numbers of shockwaves (1000, 1500, or 2000) were applied to the same kidney of all animals under fluoroscopic localization with a Stonelith V5 lithotripter. Untreated contralateral kidneys were evaluated as controls. Following HESW application, the treated and untreated kidneys were removed surgically after 24 hours or 7 days. Tissue hsp70 levels were assessed by an immunohistochemistry method. RESULTS: During early follow-up (24 hours), both treated and untreated kidneys demonstrated moderate to severe hsp70 positivity. The number of positive tubules increased as the number of shockwaves increased, and positivity became more evident, possibly because of a higher degree of tissue damage. Contralateral kidneys demonstrated a limited degree of hsp70 positivity, although it was not as evident as in the treated kidneys. Assessment of tissue hsp70 levels during late follow-up (7 days) demonstrated moderate or limited degrees of positivity in the treated kidneys. Limited or no positivity could be demonstrated in the untreated kidneys during this period. CONCLUSIONS: Taking the known traumatic effects of HESW and the results of this study into account, the increasing positivity of hsp70 in parallel with the increasing number of shockwaves led us to think about a possible limited degree of ischemia induced by this procedure, as the traumatic effects of HESW were pronounced, as judged by tissue hsp70 positivity.

Animals↗
PubMed2003

Serum lipids, lipoproteins and apolipoproteins levels in patients with nonalcoholic steatohepatitis.

GOALS/BACKGROUND: Nonalcoholic steatohepatitis (NASH) is a form of liver disease that is histologically indistinguishable from alcoholic hepatitis but occurs in persons who do not consume alcohol in excess. The objectives of this study are to measure serum levels of lipids, lipoproteins and apolipoproteins (apo AI, apo B), lipoprotein (a) [Lp (a)] in patients with nonalcoholic steatohepatitis (NASH), and to investigate the relationship with liver histology. STUDY: The scope of this study is composed of 36 patients (27 males, 9 females) with NASH, diagnosed by biochemical liver function tests, sonographic examination of liver and liver biopsy and 32 healthy adults as a control group (22 males, 10 females). Serum lipids, lipoproteins and apo AI, apo B, and Lp (a) measurements were taken in the study group and controls, and a correlation with histopathologic findings was searched for. RESULTS: Serum mean levels (+/- SD as mg/dl) of total cholesterol (201.05 +/- 34.48), triglyceride (225.94 +/- 156.50), and LDL-cholesterol (111.77 +/- 19.85) in patients with NASH were significantly higher than those of the control group (170.68 +/- 31.06; 138.81 +/- 49.96; 100.68 +/- 17.98; respectively) and serum HDL-cholesterol level (41.22 +/- 2.47) was less than that of the control group (45.06 +/- 8.32) (P = 0.017). The serum mean level of apo AI (151.54 +/- 30.90) in the study group was lower than that of the controls (160.62 +/- 22.11), but the difference was not significant (P = 0.17). However, the serum apo AI level in patients with liver fibrosis (140.62 +/- 35.62) was significantly lower than that of patients without liver fibrosis (164.57 +/- 25.47) (P = 0.01). The serum mean level of apo B (89.80 +/- 20.62) in the patients was significantly higher than the control group (73.25 +/- 25.39) (P = 0.004), but not correlate with liver histopathology. The serum Lp (a) levels in both the patients (13.09 +/- 9.61) and the controls (12.01 +/- 7.50) were not different (P = 0.61). Hypertriglyceridemia (above 220 mg/dL) had a positive correlation with steatosis of the liver (r = 0.333, P = 0.04) and a negative correlation with liver fibrosis (r = -0.438, P = 0.008). There was a significant negative correlation between apo AI and steatosis (r = -0.360, P = 0.03), inflammation (r = -0.364, P = 0.03) and fibrosis of liver (r = -0.418, P = 0.01). A positive correlation of serum LDL-cholesterol (r = 0.507, P = 0.002) and Lp(a) (r = 0.394, P = 0.01) concentrations with liver fibrosis was also noted. CONCLUSIONS: Abnormalities of lipid metabolism such as the increase of serum triglyceride, cholesterol and LDL-cholesterol level and decrease of HDL-cholesterol may be the contributing factors in the development of NASH. The decrease in apo AI and the increase in LDL and Lp (a) in patients were correlated with liver fibrosis. Apo AI may be a serum marker for liver fibrosis in patients with NASH.

Adult↗
PubMed2003

Comparative effect of intra-articular administration of hyaluronan and/or cortisone with evaluation of malondialdehyde on degenerative osteoarthritis of the rabbit's knee.

Hyaluronan and cortisone have controversial and an important role in the healing of degenerative osteoarthritis. The purpose of the research was to compare individual and combined effects of hyaluronan and cortisone on the healing of degenerative osteoarthritis and to determine the serum malondialdehyde level as a lipid peroxidation marker. A rabbit model was used in which a degenerative osteoarthritis was created in the articular cartilage by resection of anterior cruciate ligament. The rabbits divided into three groups namely were injected with hyaluronan (group A) and cortisone (group B) at days 31, 38 and 45. Cortisone at day 31 and hyaluronan at days 38 and 45 were injected to the third group (group C). We obtained blood samples from each rabbit to determine the malondialdehyde levels at days 1, 30, and 52. At day 52, 21 rabbits were sacrificed. In biopsies obtained from treated and untreated knees articular cartilage degeneration was examined by light microscopy. Histopathologically the healing rate was significantly higher in group C than the other groups. Degeneration decreased 72% in group A, 52% in group B and 88% in group C at day 22. Malondialdehyde levels were 2.056 +/- 0.37 in the control group, 1.94 +/- 0.54 in group A, 1.98 +/- 0.37 in group B and 1.55 +/- 0.41 in goup C. The malondialdehyde levels of group A and B were less than the control group (statistically insignificant, p > 0.05). But, there were statistically significant values between control group and group C (p < 0.05). The results showed that the combination of cortisone and hyaluronan is the most effective in the treatment of cartilage degeneration in the course of the ostearthritis and the malondialdehyde levels are correlated with the severity of degeneration.

Adjuvants, Immunologic↗
PubMed2002

Notalgia paresthetica with a significant increase in the number of intradermal nerves.

Notalgia paresthetica is an isolated mononeuropathy involving the skin over or near the scapula. The cause remains unknown. We histologically observed a significant increase in the number of dermal nerves in a case of notalgia paresthetica. Immunohistochemical examination using a neural marker, S-100, positively stained the nerves. Interestingly, a biopsy from perilesional skin also showed an abnormal nerve proliferation.

Administration, Topical↗
PubMedDate not supplied

Serum ubiquitin levels in patients with nonalcoholic steatohepatitis.

BACKGROUND/AIMS: Nonalcoholic steatohepatitis is increasingly recognized as the most common liver disease in patients with elevated liver enzymes. In the pathophysiology of nonalcoholic steatohepatitis, the first step is the lipid accumulation in the liver causing steatosis, the second step involves the endotoxins, cytokines and environmental toxins causing oxidative stress and lipid peroxidation, in time leading to steatohepatitis. Ubiquitin is a molecular chaperone that plays a major role in the degradation of intracellular proteins. Ubiquitin proteasome system is also considered as a cellular defense mechanism that removes damaged proteins generated by oxidative stress. In order to search for the role of ubiquitin in the pathogenesis of nonalcoholic steatohepatitis, serum levels of ubiquitin were studied in patients with nonalcoholic steatohepatitis for the first time in the literature, to our knowledge. METHODOLOGY: Eighteen patients with biopsy proven nonalcoholic steatohepatitis diagnosis (13 males and 5 females with a mean age of 41) and 16 healthy volunteers as a control group (11 males and 5 females, with a mean age of 38) were included in the study. Serum ubiquitin levels were studied by ELISA method. RESULTS: The mean serum ubiquitin level (14.13 +/- 1.46 micrograms/mL) in patients with nonalcoholic steatohepatitis was significantly elevated compared to that of the control group (7.66 +/- 0.40 micrograms/mL) (p < 0.001). No correlation was found among serum ubiquitin levels and hepatic steatosis, inflammation and fibrosis. CONCLUSIONS: Increased serum ubiquitin levels may show that the ubiquitin proteasome pathway actively participates in defending against oxidative stress in nonalcoholic steatohepatitis. Serum ubiquitin concentration may be a marker predicting the intracellular cytoprotective response against oxidative stress rather than the degree of liver damage in pathogenesis of nonalcoholic steatohepatitis. Ubiquitin proteasome system based therapies may have a place in the treatment of patients with nonalcoholic steatohepatitis in the future.

Adult↗