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Biomedical subjects

H Erdem

Publications and source records attributed to H Erdem.

At least 19 recordsLinked to original sources
PubMed2006

Peripheral insulin resistance in patients with Behçet's disease.

In this study, we examined peripheral insulin resistance in patients with Behçet's disease (BD) characterized by chronic inflammation and endothelial dysfunction. Fourteen patients with BD and 15 healthy controls were recruited to the study. Insulin resistance was investigated by the hyperinsulinaemic-euglycaemic glucose clamp technique. BD patients displayed an enhanced rate of insulin resistance compared to healthy controls (P = 0.014). The insulin sensitivity (M), measured as the glucose utilization rate under steady-state conditions of euglycaemia, was significantly decreased (P = 0.001) in BD patients compared to the controls (4.09 +/- 0.16 vs. 5.60 +/- 0.27 mg/kg/min). The C-reactive protein (CRP) level, but not the erythrocyte sedimentation rate (ESR), was significantly related to the presence of insulin resistance (CRP: r(s) = 0.589, P = 0.27; ESR: r(s) = 0444, P = 0112), whereas no relationship was found between the M-value and ESR or CRP. We conclude that patients with BD exhibit peripheral insulin resistance; this could be explained as the diverse consequences of inflammation and endothelial dysfunction in BD.

Adult↗
PubMed2005

Serum interleukin-18 levels in patients with Behçet's disease. Is its expression associated with disease activity or clinical presentations?

Interleukin (IL)-18 is a proinflammatory cytokine which plays a crucial role in T helper (Th)1 type immune response. The aim of this study is to investigate the relationship of serum levels of IL-18 with disease activity and clinical presentations in patients with Behcet's disease (BD). Sixty patients with BD and 20 healthy controls were included in the study. Patients were grouped as having active or inactive disease according to the Leeds activity score. They were also separated as a systemic involvement or mucocutaneous symptoms only. Patients with systemic involvement were further grouped according to the presence of ocular, articular and vascular involvement. IL-18 levels were significantly higher in all patient subgroups as compared to healthy controls and found to be correlated with the activity score in patients having active disease. In conclusion, this cytokine participates in the pathogenesis of BD and its levels are correlated with the disease activity. Detection of increased levels of IL-18 in patients with inactive disease implies that Th1 activation and subclinical inflammation persist during the inactive period of the disease.

Adult↗
PubMed2005

Chimerical anti-TNF-alpha, infliximab, inhibits neutrophil chemotaxis and production of reactive oxygen species by blocking the priming effect of mononuclear cells on neutrophils.

Clinical experience with anti-tumor necrosis factor alpha (anti-TNF-alpha) agents implies that these agents can cause a rapid onset amelioration of the symptoms and laboratory parameters in some inflammatory diseases. Precise explanation of this fast antiinflammatory action is not known. The aim of our study is to investigate the direct and indirect effects of anti-TNF agents on the chemotaxis and reactive oxygen species (ROS) production of neutrophils. For this purpose, isolated neutrophil cultures (INCs) and mixed leukocyte cultures were prepared from the venous blood of healthy subjects. Those cultures were separated to different groups according to the presence of anti-TNF or the stimulation of phytohemagglutinin (PHA). In this study, anti-TNF treatment did not change the migration ability of neutrophils in INCs. However, we established that chimerical anti-TNF-alpha, infliximab, inhibits neutrophil chemotaxis and production of ROS by blocking the priming effect of PHA-stimulated circulating mononuclear cells. These results may explain, at least partly, the rapid onset antiinflammatory actions of these agents observed in clinical practice.

Adult↗
PubMed2005

Antibiotic resistance in pathogenic Streptococcus pneumoniae isolates in Turkey.

Streptococcus pneumoniae causes various human infections such as meningitis, septicemia, otitis media, sinusitis, and pneumonia. Antibiotic resistance has already been reported with increasing frequency worldwide and is spreading. The earliest studies on pneumococcal antibiotic resistance go back to the late 1980s in Turkey. The resistance patterns have elevated with stepwise increments since then. By the beginning of 2005, approximately 40% of pneumococci were resistant to penicillin and nearly one-fifth of resistant isolates present high-level penicillin resistance. This proves that penicillin is still a good alternative for nonmeningeal infections. In addition, no ceftriaxone resistance have been reported in local Turkish studies, but cefuroxime, a second-generation cephalosporin, was recorded to have (10.8-20%) resistance rates. The most frequently assessed antibiotics other than penicillin in Turkish studies include erythromycin (4-19.4%), chloramphenicol (2-10%), clindamycin (2.5-13%) and tetracycline (13-28.6%) and all have various resistance profiles. On the other hand, nearly all or almost all of the isolates evaluated in Turkish studies are susceptible to rifampicin, quinolones, linezolid, quinupristin-dalfopristin and telithromycin. All these non-beta-lactam antibiotics except the tetracyclines are within acceptable limits of empirical approaches. Tetracycline must be used cautiously. In addition, trimethoprim sulfamethoxazole cannot be prescribed in probable pneumococcal infections since more than half of the isolates are nonsusceptible.

Anti-Bacterial Agents↗
PubMed2005

Gram-negative bacterial resistance to cephalosporins in community-acquired infections in Turkey.

Cephalosporins are widely used and trustworthy antibiotics in daily medical practice. Although antibacterial resistance has been reported in hospital wards, there are less data for community-acquired infections. In this study we investigated the cephalosporin susceptibility profiles of community-acquired Gram-negative bacteria isolates in Sivas Kizilay Medical Center (Turkey) between March 2002 and March 2003. In our study, 949 Escherichia coli, 165 Proteus spp., 97 Enterobacter spp., 24 Klebsiella spp and 84 Pseudomonas aeruginosa strains were evaluated. Cefepime seemed to be the most effective antibiotic against our community-acquired Gram-negative isolates. Resistance to this drug was 19.3% for P. aeruginosa and around 0-10.6% for enteric bacteria. Enteric pathogen resistance ranged between 44.3-100% for cefazolin, 25-51.9% for cefuroxime, 4.8-25.3% for ceftriaxone, 5.4-14.5% for ceftazidime. Resistance in enteric pathogens to gentamicin ranged between 5.8-15.4%, to amikacin between 3.8-6.25%, to ciprofloxacin between 6.7-20%. 8.1% of P. aeruginosa were resistant to ciprofloxacin. With these profiles the aminoglycosides and ciprofloxacin resemble highly effective cephalosporins like cefepime. On the contrary, first- and second-generation cephalosporins, trimethoprim-sulfamethoxazole, ampicillin and ampicillin-sulbactam are no longer used in probable Gram-negative bacterial infections in our region. Since treatment based on cephalosporins was less efficacious than expected in community-acquired infections, urgent measures are needed to limit antibacterial resistance outside of hospitals.

Anti-Bacterial Agents↗
PubMed2002

Comparison of synovial MMP-1 and TIMP-1 levels in patients with various inflammatory arthritides: is there any difference between rheumatoid arthritis, Behçet's disease and familial Mediterranean fever?

The purpose of this study was to investigate synovial levels of matrix metalloproteinase-1 (MMP-1), known to break down collagen, and tissue inhibitor of metalloproteinase (TIMP-1), its natural antagonist, in patients with various inflammatory disorders. Eighty-five patients with different inflammatory arthritides (20 Behçet's disease, 20 familial Mediterranean fever, 26 rheumatoid arthritis and 19 osteoarthritis) were enrolled in the study. Synovial MMP-1 and TIMP-1 levels were measured by two-step sandwich ELISA. There were significant differences between study and control groups regarding erythrocyte sedimentation rate, C-reactive protein, MMP-1 and TIMP-1 values. The synovial MMP-1 levels of patients with Behçet's disease and familial Mediterranean fever were no different from those in patients with rheumatoid arthritis, but significantly higher than those of patients with osteoarthritis. The synovial TIMP-1 levels in patients with osteoarthritis were higher than those of patients with the other three diseases, among which the difference was not statistically significant, and the difference between osteoarthritis and the others was statistically significant. Because of the detection of similar levels of synovial MMP-1 in patients with familial Mediterranean fever, Behçet's disease and rheumatoid arthritis, we conclude that the absence of erosions in patients with familial Mediterranean fever and Behçet's disease may be explained by MMP-1 being a marker of cytokine-driven inflammation, or by the short-lived and transient nature of the arthritis observed in these patients.

Adult↗
PubMed2002

Vitamin A and beta-carotene levels in plasma, corpus luteum and follicular fluid of cyclic and pregnant cattle.

This study was carried out to examine the relationship between the corpus luteum (CL) weight, CL and follicle diameters and progesterone, beta-carotene and vitamin A levels in reproductive organs of cattle obtained from the slaughterhouse. The beta-carotene and vitamin A levels were determined in plasma, CL and follicular fluid (FF) using a spectrophotometric method at different stages of the oestrous cycle (n=40) and at 3-6 months of pregnancy (n=10). The diameters of the CL and follicle were measured using ultrasonography. Plasma progesterone concentrations were determined by an enzyme immunoassay method. The vitamin A levels of the plasma, CL and FF were not related to each other. The highest plasma vitamin A levels were observed in the proestrus and oestrus, at which periods follicular activity dominates. The vitamin A levels in the CL and FF were negatively related to the weight and diameter of the CL and the diameter of follicle, respectively. In contrast to vitamin A, beta-carotene concentrations of plasma, CL and FF were significantly correlated with each other. The highest beta-carotene levels in the plasma, CL and FF were found during pregnancy when there is maximal luteal function, and the beta-carotene level of the CL was significantly correlated with the weight and diameter of CL. Furthermore, the intrafollicular beta-carotene level was negatively correlated with the follicle diameter. There was a positive correlation between plasma progesterone level and the weight and diameter of the CL, but a negative correlation between plasma progesterone level and follicle diameter. Moreover, plasma, FF and CL beta-carotene levels were positively correlated with plasma progesterone levels. This study revealed that beta-carotene levels in the plasma, CL and FF were influenced by the stage of the oestrous cycle or the pregnancy and were related to bovine luteal function without depending on vitamin A.

Animals↗
PubMed2001

Insulin resistance in non-alcoholic steatohepatitis.

BACKGROUND: Non-alcoholic steatohepatitis is a chronic liver disease that is capable of progressing to end-stage liver disease, but generally has a benign course. Obesity, non-insulin-dependent diabetes mellitus and hyperlipidaemia are the most common associations of the disease. AIMS: To investigate the insulin resistance in patients with non-alcoholic steatohepatitis who have no other causes of insulin resistance such as obesity, diabetes mellitus, and hyperlipidaemia. PATIENTS: Thirteen patients (7 male, 6 female) with non-alcoholic steatohepatitis and 12 (6 male, 6 female) healthy volunteers. METHODS: All patients and healthy volunteers were submitted to biochemical tests and hyperinsulinaemic euglycaemic insulin clamp technique. RESULTS: Basal insulin levels and C-peptide levels were significantly higher in non-alcoholic steatohepatitis group than in controls (p<0.001 and p<0.001, respectively). Hyperinsulinaemic euglycaemic insulin clamp technique revealed lower glucose utilization in the non-alcoholic steatohepatitis group and the difference was statistically significant (p<0.001). CONCLUSIONS: Our study revealed marked hyperinsulinaemia and insulin resistance in patients with non-alcoholic steatohepatitis. Hyperinsulinaemia and insulin resistance may contribute to pathogenesis of nonalcoholic steatohepatitis.

Adult↗
PubMed2001

Autosomal recessive spastic ataxia of Charlevoix-Saguenay in two unrelated Turkish families.

Autosomal recessive spastic ataxia of Charlevoix-Saguenay is an early onset form of hereditary spastic paraplegia with a peculiar clinical presentation. In addition to cerebellar findings which manifest first with ataxic gait in early life and spasticity, on an evolutionary basis, there is axonal neuropathy, prominent myelinated fibers in the optic fundus, and evidence of cerebellar atrophy that can be detected by cranial MRI. Intelligence is usually normal, however lower IQs have also been documented. This disorder mainly originates from the Charlevoix-Saguenay region of Quebec. Here, we report two Turkish families linked to the disease locus on chromosome 13 q12. There was homozygosity and segregation of disease haplotypes in both families. This form of spastic ataxia may be more common than originally presumed.

Adolescent↗
PubMed2001

Effect of sodium valproate on somatosensory evoked potentials in juvenile myoclonic epilepsy.

We analysed somatosensory evoked potentials (SEPs) in the patients with juvenile myoclonic epilepsy (JME) in order to find out if sodium valproate (VPA) affects SEP latencies and amplitudes. SEPs were studied in 23 patients with JME receiving VPA monotherapy, eight patients with JME not receiving VPA, and a control group consisting of 20 healthy subjects. The N20, P24, and N34 latencies bilaterally were significantly prolonged in the JME group receiving VPA as compared with the control group. In the untreated patients the P24, and N34 latencies bilaterally and the N20-P24 interpeak latency on the right, were significantly prolonged as compared with the control group. In addition, in the patient group without treatment, the N20-P24 amplitudes bilaterally and the P24-N34 amplitudes from left sided median nerve stimulation, were greater as compared with the control group. In the SEP latencies, no significant differences were observed between the patients treated and untreated with VPA. Regarding SEP amplitudes, in the untreated group, while the N20-P24 amplitudes from right sided median nerve stimulation were significantly enhanced, all the other amplitudes also showed increase, even insignificant, as compared with the patients treated by VPA. These findings suggest that the SEPs latencies are prolonged, and the amplitudes are enhanced in JME. The changes of the SEPs latency in JME could be due to abnormal synaptic transmission and not influenced by VPA. On the other hand, the increase of the amplitude tends to be lowered by VPA.

Adolescent↗
PubMed2001

Aphasia in multiple sclerosis.

Aphasia has rarely been reported in multiple sclerosis (MS). In this article a case with MS presenting as purely global aphasia during an exacerbation of MS is reported with clinical and MRI (magnetic resonance imaging) findings. MRI demonstrated giant plaques mimicking a cerebral tumour with surroundings characterised by oedematous transformations in the left frontal and parietal lobes.

Adult↗
PubMed2001

Prenatal diagnosis of spinal muscular atrophy in Turkish families.

Prenatal diagnosis of childhood proximal spinal muscular atrophy (SMA) is carried out by the detection of homozygous deletions of survival motor neuron (SMN; exons 7 and 8) and neuronal apoptosis inhibitory protein (NAIP; exons 5 and 6) genes located in 5q13 chromosomal region. In Hacettepe University, Department of Medical Biology, 203 postnatal molecular diagnoses of SMA have been carried out since October 1994 and prenatal diagnosis in subsequent pregnancies to couples who previously had an affected child became possible. Between January 1996 and December 1999 totally 41 SMA families were analyzed by detecting homozygous deletions of SMN and NAIP genes for prenatal counseling. Fetal DNAs were obtained from amniotic fluid and chorionic villus samples. 8/41 (20%) fetal samples were found to be affected and these pregnancies were terminated. It was interesting to find that 2 fetuses had only SMN deletions, however their affected siblings had both SMN and NAIP gene deletions.

Cyclic AMP Response Element-Binding Protein↗
PubMed2000

A case of Churg-Strauss syndrome presenting with cortical blindness.

A 46-year-old woman with a sudden sight loss due to infarction of the occipital lobes is reported. The association of pulmonary disease, digital ischaemia, polyneuropathy and peripheral eosinophilia led to a diagnosis of Churg-Strauss syndrome. Her vision partially improved by a treatment with steroids and monthly i.v. cyclophosphamide. To our knowledge, this is the first case of CSS with a sudden loss of vision due to bilateral occipital infarction.

Administration, Oral↗
PubMed2000

Fulminant hepatic failure as the initial manifestation of primary hepatocellular carcinoma.

A 20-year-old male, with no history of chronic liver disease, presented with fulminant hepatic failure. The cause was not established until post mortem when it was found that he had a primary hepatocellular carcinoma in a non-cirrhotic liver. To our knowledge, this is the third report of hepatocellular carcinoma presenting in this manner. Although rare, primary malignancies of the liver should be considered in the differential diagnosis of fulminant hepatic failure, especially when other more common causes are excluded.

Adult↗
PubMed1999

Bilateral globus pallidus lesions in a patient with Tourette syndrome and related disorders.

BACKGROUND: The neuroanatomic and pathologic basis of Tourette's syndrome or related disorders such as obsessive-compulsive disorder and attention deficit-hyperactivity disorder remains unknown. Although a substantial body of neuroimaging and other data implicate basal ganglia and some point out specifically the globus pallidus in the etiopathogenesis of these three related disorders, no clear or pathologically significant isolated lesions restricted to this region have yet been demonstrated, with the exception of obsessive-compulsive disorder. METHODS: A seventeen-year-old male case of Tourette syndrome with comorbid obsessive-compulsive disorder, attention deficit-hyperactivity disorder, stuttering and gait disturbance, who had negative family history is presented. RESULTS: The patient has failed to respond to drug treatment and his MRI scan revealed bilateral and symmetrical globus pallidus lesions with specific "tiger's eye" appearance of unknown etiology. CONCLUSIONS: Well-localized lesions in the globus pallidus support growing data suggesting the involvement of this brain region in Tourette syndrome and related disorders.

Adolescent↗
PubMed1999

Salivary sialic acid, protein, salivary flow rate, pH, buffering capacity and caries indices in subjects with Down's syndrome.

OBJECTIVES: The aim of this study was to compare salivary sialic acid, protein, salivary flow rate, pH and buffering capacity and caries indices between subjects with Down's Syndrome and healthy controls. METHODS: Unstimulated mixed saliva was collected from 26 Down's syndrome subjects and 25 healthy subjects of age range 6-24 years. Total protein was determined by the method of Lowry and total sialic acid using Ehrlich reagent. Laemmli SDS-polyacrylamide gel electrophoresis was also carried out. RESULTS: Buffering capacity and pH were quite similar for both groups. For permanent dentition subjects pH was significantly higher (P = 0.03) in the Down's syndrome group. The salivary flow rate of the Down's syndrome subjects was significantly lower (P < 0.01) than that of healthy controls and the Down's syndrome subjects' salivary protein and sialic acid levels were significantly higher (P < 0.001). The ratios of total sialic acid to total protein were significantly higher (P < 0.001) in the Down's syndrome group. However, salivary sialic acid expectoration rates, a means of compensating for flow rate differences, were significantly lower (P = 0.01) in the Down's syndrome subjects than in controls. Electrophoresis revealed no significant differences between the protein bands of the groups. There were no significant differences in caries indices between groups, even when compensated for age, nor in the salivary parameters within groups between sexes. CONCLUSIONS: Total salivary sialic acid in Down's syndrome subjects, higher in terms of levels but lower in terms of expectoration rates, was significantly different from that of controls of similar caries indices.

Adolescent↗
PubMed1999

Deletion analysis in Turkish patients with spinal muscular atrophy.

Childhood proximal spinal muscular atrophy (SMA) is an autosomal recessive disorder which presents as a severe, intermediate or mild condition. Here we present the molecular analysis of SMA candidate genes, the survival motor neuron gene (SMN), the neuronal apoptosis inhibitory protein gene (NAIP) and the p44 gene. Deletion frequency rate of these candidate genes is 93% in 106 Turkish SMA patients. Various deletion haplotypes by using genotypes of SMN, NAIP and p44 genes are constructed. Haplotype A, which is the deletion of all three involved genes, was found only in the most severe group with an early onset of usually less than 2 months of age.

Cyclic AMP Response Element-Binding Protein↗