S Cağlar

Publications (45)273.5 Total impact

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  Available from: hasancaglarugur.com

  Article: Infection-related atlantoaxial subluxation in two adults: Grisel syndrome or not?

  H C Ugur, S Cağlar, A Unlu, A Erdem, Y Kanpolat
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  ABSTRACT: Grisel's syndrome involves the subluxation of the atlanto-axial joint from inflammatory ligamantous laxity following an infectious process in the head or neck. It is a rare disease usually affecting children, but infrequent adult cases do occur. Today, due to the widened use of antibiotics and availability of MR imaging, some cases presenting with neck pain, resulting from the infectious inflammation of C1 and C2 but without pronounced subluxation, can be a challenging problem for most neurosurgeons. Several theories have been proposed to explain the pathogenesis of inflammatory subluxation. The primary treatment of Grisel's syndrome is medical. The underlying infectious organism must be isolated and appropriate antibiotics must be prescribed. The subluxation is reduced in holter or skeletal traction. This paper reports two cases of infection-related atlanto-axial subluxation in two adults. The literature on this subject is briefly reviewed.
  Acta Neurochirurgica 02/2003; 145(1):69-72. · 1.52 Impact Factor
• Article: Multiple spinal intramedullary cavernous angioma: case report.

  H Balaban, Sener HO, I Erden, S Cağlar, A Sahin, N Yücemen
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  ABSTRACT: Spinal cavernous angiomas frequently accompany to cranial cavernous angiomas. Multiple spinal cord cavernous angiomas are very rare and to authors knowledge, only one case has been described having multiple intramedullary cavernous angiomas without cranial involvement until now. In this report, we present a case with acute paraplegia who had thoracic and cervical intramedullary cavernous angiomas and normal cranial magnetic resonance imaging.
  Clinical Neurology and Neurosurgery 08/2001; 103(2):120-2. · 1.58 Impact Factor
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  Available from: Yasemin Genc

  Article: Surgical anatomic evaluation of the cervical pedicle and adjacent neural structures.

  H C Uğur, A Attar, A Uz, I Tekdemir, N Egemen, S Cağlar, Y Genç
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  ABSTRACT: Although several clinical applications of transpedicular screw fixation in the cervical spine have been documented recently, few anatomic studies concerning the cervical pedicle are available. This study was designed to evaluate the anatomy and adjacent neural relationships of the middle and lower cervical pedicle (C3-C7). The main objective is to provide accurate information for transpedicular screw fixation in the cervical region and to minimize complications by providing a three-dimensional orientation. Twenty cadavers were used to observe the cervical pedicle and its relationships. After removal of the posterior bony elements, including spinous processes, laminae, lateral masses, and inferior and superior facets, the isthmus of the pedicle was exposed. Pedicle width, pedicle height, interpedicular distance, pedicle-inferior nerve root distance, pedicle-superior nerve root distance, pedicle-dural sac distance, medial pedicle-dural sac distance, mean angle of the pedicle, root exit angle, and nerve root diameter were measured. The results indicate that there was no distance between the pedicle and the superior nerve root and between the pedicle and the dural sac in 16 specimens, whereas there was a slight distance in the lower cervical region in the 4 other specimens. The mean distance between the pedicle and the inferior nerve root for all specimens ranged from 1.0 to 2.5 mm. The mean distance between the medial pedicle and the dural sac increased consistently from 2.4 to 3.1 mm. At C3-C7, the mean pedicle height ranged from 5.2 to 8.5 mm, and the mean pedicle width ranged from 3.7 to 6.5 mm. Interpedicular distance ranged from 21.2 to 23.2 mm. The mean root exit angle ranged from 69 to 104 degrees, with the largest angle at C3 and the smallest at C6. The mean angle of the pedicle ranged from 38 to 48 degrees. The nerve root diameter increased consistently from 2.7 mm at C3 to 3.8 mm at C6 and then decreased to 3.7 mm at the C7 level. Differences in measurements were considered statistically significant at levels ranging from P < 0.05 to P < 0.01. This study indicates that improper placement of the pedicle screw medially and superiorly in the middle and lower cervical spine should be avoided and that the anatomic variations between individuals should be established by measurement.
  Neurosurgery 11/2000; 47(5):1162-8; discussion 1168-9. · 2.79 Impact Factor
• Article: Effects of angiotensin converting enzyme and angiotensin II receptor inhibition on impaired fibrinolysis in systemic hypertension.

  Y Erdem, C Usalan, I C Haznedaroğlu, B Altun, M Arici, U Yasavul, C Turgan, S Cağlar
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  ABSTRACT: Abnormalities in fibrinolysis have been reported in hypertension. Angiotensin converting enzyme (ACE) inhibitors have been shown to improve altered fibrinolytic balance in hypertensive patients. It has not been documented, however, whether this is due to a decrease in angiotensin II (Ang-II) generation or is a consequence of elevated local levels of bradykinin. Accordingly, the aim of this study was to determine the effects of an ACE inhibitor (perindopril) and an Ang-II receptor antagonist (losartan) on fibrinolytic kinetics. We have examined the serum levels of the plasminogen activator inhibitor type-1 (PAI-1) antigen and activity, tissue plasminogen activator (t-PA) antigen and activity, soluble thrombomodulin (sTM), and tissue factor pathway inhibitor (TFPI) before and after reaching the target blood pressure (<140/90 mm Hg) in 13 hypertensive patients receiving perindopril (mean age 40+/-11 years, 6 women, 7 men) and in 12 patients receiving losartan (mean age 38+/-9 years, 6 women, 6 men). We also compared the baseline fibrinolytic activity of hypertensive patients with that of 12 normotensive control persons (mean age 40+/-9 years, 6 women, 6 men). The mean basal plasma levels of PAI-1 antigen, PAI-1 activity, and sTM were significantly higher in the hypertensive patients than in normal controls (P<.005). The values of other analytes were similar in both groups. Increased plasma levels of PAI-1 antigen, PAI-1 activity, and sTM were reduced in patients after they were given perindopril and losartan (P<.005); the reductions in losartan-receiving group were more pronounced (P<.05). There were no significant effects on the plasma levels of t-PA antigen, t-PA activity, and TFPI in patients receiving the two therapeutic regimens (P>.05). In conclusion, chronic hypertension is associated with hypofibrinolysis. The beneficial effect of ACE inhibitors on fibrinolysis seems to be related to the blockade of Ang-II, and increased kinin activity does not appear to play a major role.
  American Journal of Hypertension 11/1999; 12(11 Pt 1):1071-6. · 3.18 Impact Factor
• Article: Serum thrombopoietin levels in haemodialysis patients: involvement of arteriovenous fistula.

  B Altun, M Arici, I C Haznedaroğlu, C Usalan, Y Erdem, U Yasavul, C Turgan, S Cağlar, S Kirazli
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  ABSTRACT: Thrombopoietin (Tpo) is a recently cloned growth factor which plays a critical role in the regulation of thrombopoiesis. Tpo has also been shown to stimulate in vitro and in vivo erythroid cell growth. Although Tpo transcripts were detected in hepatocytes, proximal tubules and endothelium, mechanisms regulating the level of circulating Tpo have not been fully delineated. Changes in the vessel wall and blood flow in arteriovenous fistula (AVF) might alter Tpo activity. Serum thrombopoietin levels and serum erythropoietin levels in samples concurrently obtained from venous returns of AVF and contralateral peripheral veins in 31 haemodialysis patients were determined and compared with 12 healthy controls. Levels were also compared between 14 haemodialysis patients (group I) treated with recombinant human erythropoietin (rHu-Epo) and 17 haemodialysis patients (group II) not requiring rHu-Epo. Serum Tpo levels (44.8 +/- 23.9 pg/ml, vs 129.9 +/- 113.6 pg/ml, P<0.05) and platelet counts (194 +/- 55, 10(6)/ml vs 273 +/- 94. 10(6)/ml, P<0.05) of haemodialysis patients were lower than healthy controls. Serum Tpo levels were inversely correlated with platelet counts in the control group (R=-0.61, P<0.05), but not in haemodialysis patients. Tpo concentrations of AVF samples were lower than peripheral venous samples (31.6 +/- 17.7 pg/ml vs 44.8 +/- 23.9 pg/ml, P=0.001). No significant difference was present between the serum Tpo concentrations of haemodialysis patients in group I and group II. Serum Tpo levels were not correlated with haemoglobin levels or serum erythropoietin levels in haemodialysis patients. Decreased serum Tpo levels despite low platelet counts in haemodialysis patients suggest that the proposed feedback mechanism of platelet uptake of Tpo is not fully operative in these patients. Moreover, AVF might affect the local production and/or catabolism of this growth factor.
  Nephrology Dialysis Transplantation 10/1999; 14(9):2173-7. · 3.40 Impact Factor
• Source

  Available from: oxfordjournals.org

  Article: Hypernatraemia and polyuria due to high-dose colchicine in a suicidal patient.

  C Usalan, B Altun, S Ulusoy, Y Erdem, U Yasavul, C Turgan, S Cağlar
  Nephrology Dialysis Transplantation 07/1999; 14(6):1556-7. · 3.40 Impact Factor
• Article: Protein Z levels in haemodialysis patients.

  C Usalan, Y Erdem, B Altun, M Arici, I C Haznedaroğlu, U Yasavul, C Turgan, S Cağlar
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  ABSTRACT: Protein Z (PZ) is a vitamin K-dependent protein isolated from human and bovine plasmas. Although the exact role of PZ in the haemostatic system is presently unknown, it is suggested that PZ deficiency may cause bleeding tendency. Haemostatic alterations in end-stage renal failure (ESRF) are certainly complex and involve several abnormalities in the coagulation and fibrinolytic system. In order to elucidate the detail of the haemostasis in ESRF, we aimed to investigate PZ activity in haemodialysis patients. Therefore, we compared plasma PZ levels in 10 haemodialysis patients (6 M, 4 F, mean age 36+/-11) and 10 healthy normal controls (5 M, 5 F, mean age 34+/-8) in this study. We found mean plasma PZ levels in haemodialysis patients and healthy controls 6.95+/-2.93 microg/ml and 3.06+/-0.81 microg/ml, respectively (p<0.005). Increased level of PZ which influences the action of thrombin on its protein substrates and inhibitors may contribute to the haemostatis alterations in ESRF patients, in addition to other well known abnormalities in the coagulation and fibrinolytic system.
  International Urology and Nephrology 01/1999; 31(4):541-5. · 1.47 Impact Factor
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  Available from: oxfordjournals.org

  Article: Effect of enalapril on exaggerated erythropoietin response to phlebotomy in erythrocytosic renal transplant patients.

  C Usalan, Y Erdem, M Cağlar, B Altun, M Arici, M Bakkaloğlu, U Yasavul, C Turgan, S Cağlar
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  ABSTRACT: Exaggerated erythropoietin (EPO) response to phlebotomy regardless of the baseline EPO levels have been shown in patients with post-transplant erythrocytosis (PTE) and administration of angiotensin-converting enzyme inhibitors (ACE-1) seems to be effective in controlling PTE. However, the mechanism of this ACE-1 induced reduction in haematocrit (Hct) is not well known. Although some authors have suggested that ACE-1 may reduce EPO secretion, this is still controversial. The aim of the present study was to assess the effect of a single dose ACE-1 on exaggerated EPO response to phlebotomy. In this study, we compared serum EPO and renin (PRA) levels of 10 PTE patients, 10 non-PTE patients and 10 healthy blood donors before and after phlebotomy. The effects of a single dose of ACE-1 (enalapril, 5 mg p.o.) in PTE patients were also evaluated in the second phlebotomy. While the mean basal serum EPO level was significantly higher in the PTE group than the other two groups (P<0.01), the mean basal PRA levels did not differ significantly between these groups. Serum EPO and PRA levels increased significantly after the phlebotomy (P<0.001) and exaggerated EPO response to phlebotomy was suppressed by single dose enalapril (P<0.001) in the PTE patients. The present study has shown that the renin angiotensin system plays an important role in EPO formation and the Hct lowering effect of the ACE-1 is through reduction of EPO in PTE patients.
  Nephrology Dialysis Transplantation 12/1998; 13(11):2884-9. · 3.40 Impact Factor
• Article: Severe hyponatremia probably resulting from inappropriate secretion of antidiuretic hormone. A rare initial presentation of tuberculosis.

  C Usalan, A Nar, Y Erdem, U Yasavul, C Turgan, S Cağlar
  Nephron 11/1998; 80(2):237-8. · 13.26 Impact Factor
• Article: Recombinant human erythropoietin increases platelet aggregation in chronic hemodialysis patients.

  N Sayinalp, Y Erdem, O Ilhami Ozcebe, Y Büyükaşik, S Cağlar, S V Dündar
  Thrombosis Research 06/1998; 90(4):195-8. · 2.44 Impact Factor
• Article: Rapidly progressive glomerulonephritis associated with hepatitis C virus infection.

  C Usalan, Y Erdem, B Altun, A Nar, U Yasavul, C Turgan, S Cağlar
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  ABSTRACT: Glomerular disease often accompanies a wide variety of liver diseases, including acute or chronic hepatitis. A striking association between hepatitis B virus and glomerulonephritis particularly membranous glomerulonephritis has been reported by various authors. It is not surprising, therefore, that hepatitis C virus (HCV) infection has been recently associated with the development of various types of glomerulonephritis. The principal type of glomerulonephritis associated with HCV infection is either cryoglobulinemic or non-cryoglobulinemic membranoproliferative glomerulonephritis. However, other types of glomerular lesions were seen in the clinical course of HCV infection. We report a rare case of a 20-year-old woman who developed rapidly progressive glomerulonephritis (RPGN) during the course of the active HCV infection. Whether this case represents a true association or a coincidental association is not known.
  Clinical nephrology 03/1998; 49(2):129-31. · 1.17 Impact Factor
• Source

  Available from: oxfordjournals.org

  Article: Role of erythropoietin in pathogenesis of post transplant erythrocytosis (PTE) and mechanism of losartan's efficiency.

  B Altun, M Arici, U Yasavul, C Turgan, S Cağlar
  Nephrology Dialysis Transplantation 04/1997; 12(3):626-7. · 3.40 Impact Factor
• Article: Rapidly progressive glomerulonephritis associated with pregnancy.

  C Usalan, Y Erdem, U Yasavul, C Turgan, S Cağlar
  Nephron 02/1997; 77(1):118. · 13.26 Impact Factor
• Article: Severe renal vasoconstriction and anuria after intravenous urography in a patient with renal impairment.

  M Arici, Y Erdem, B Altun, F Balkanci, U Yasavul, C Turgan, S Cağlar
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  ABSTRACT: Acute renal failure caused by radiocontrast agents remains a severe problem, particularly in patients with risk factors. There is debate concerning the pathophysiology of contrast media-induced acute renal failure, including, but not limited to, renal ischemia or tubular damage. Vascular ischemia is considered a major contributor because consistent changes in renal hemodynamics have been recorded experimentally. We describe a patient who has a typical course of contrast-associated renal failure manifested by severe renal vasoconstriction and backflow of the contrast agent during renal angiography performed after 6 days of an intravenous urography. Such degree of renal vasoconstriction is noteworthy in that this particular case might serve as a model in delineation of the pathogenetic mechanisms of acute renal failure after contrast media administration.
  American Journal of Kidney Diseases 10/1996; 28(3):454-6. · 5.43 Impact Factor
• Article: Severe hyponatremia due to SIADH provoked by acute intermittent porphyria.

  C Usalan, Y Erdem, B Altun, M Gürsoy, I Celik, U Yasavul, C Turgan, S Cağlar
  Clinical nephrology 07/1996; 45(6):418. · 1.17 Impact Factor
• Article: Circulating thrombomodulin as a molecular marker of endothelium damage in renal transplant recipients.

  I C Haznedaroğlu, Y Erdem, A U Yalcin, N M Sayinalp, U Yasavul, C Turgan, S Cağlar, S Dündar, S Kirazli
  Nephron 02/1996; 73(3):486-7. · 13.26 Impact Factor
• Article: Ciclosporin A in lupus nephritis.

  Y Erdem, A U Yalçin, O Oymak, U Yasavul, C Turgan, S Cağlar
  Nephron 02/1996; 72(2):332. · 13.26 Impact Factor
• Article: Severe hypoglycemia in a patient with chronic renal failure due to amyloidosis.

  A Topeli, Y Erdem, A U Yalçin, O Oymak, M Hayran, U Yasavul, C Turgan, S Cağlar
  Nephron 02/1996; 72(2):330-1. · 13.26 Impact Factor
• Article: Evisceration of the eye in a renal transplant recipient with cytomegalovirus chorioretinitis.

  N Başçil, Y Erdem, A U Yalçin, M Hayran, I C Haznedaroğlu, U Yasavul, C Turgan, S Cağlar
  American Journal of Nephrology 02/1996; 16(4):367-8. · 2.54 Impact Factor
• Article: Local fibrinolysis in native arteriovenous fistulas of haemodialysis patients.

  I C Haznedaroğlu, Y Erdem, I Celik, N M Sayinalp, S V Dündar, S Cağlar, S Kirazli
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  ABSTRACT: This study was designed to evaluate local alterations of the fibrinolytic process in patent-functional native arteriovenous fistulas of patients on maintenance haemodialysis. For this aim, the concentrations of the main components of the fibrinolytic system were determined in plasma samples taken simultaneously from arteriovenous fistulas and contralateral upper extremity concurrent large veins of haemodialysis patients. Twelve patients (6 women and 6 men, age 36 +/- 8 years) with end-stage renal disease on maintenance haemodialysis and 15 non-smoker healthy volunteers (8 women and 7 men, age 31 +/- 10 years) with normal renal function were included in the study. The fibrinolytic parameters, except alpha 2-antiplasmin, were found to be elevated in arteriovenous fistulas of haemodialysis patients as compared with opposite upper extremity large veins of the same patients (p < 0.005). Increments in fibrinolytic parameters including tissue plasminogen activator antigen, urokinase-type plasminogen activator antigen and activity, and plasminogen activity together with lower alpha 2-antiplasmin levels favor activation of fibrinolysis, except for higher alpha 2-macroglobulin concentrations, in arteriovenous fistula. The study suggests that the fibrinolytic process is locally activated in arteriovenous fistulas of haemodialysis patients.
  Blood Purification 01/1996; 14(3):227-33. · 2.10 Impact Factor