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Biomedical subjects

Ahmet Kalkan

Publications and source records attributed to Ahmet Kalkan.

At least 19 recordsLinked to original sources
PubMed2006

Detection of Molluscum contagiosum virus (MCV) subtype I as a single dominant virus subtype in Molluscum lesions from a Turkish population.

BACKGROUND: Molluscum contagiosum has a worldwide occurrence and its primary mode of transmission is via direct human contact including sexual means. The aim of the study was to implement a polymerase chain reaction-based assay for detection and subtyping of Molluscum contagiosum virus (MCV) in skin lesions diagnosed with molluscum contagiosum in a large regional teaching hospital in Turkey. METHODS: For this purpose, a total of 61 patients were included in the study. Randomly selected single lesion from each patient was used to extract DNA material and a specific PCR reaction amplifying 393-bp- and 575-bp-long regions from MCV genome was used in the detection. Subtyping was carried out by digestion of the amplified 575-bp product with restriction endonuclease enzyme BamHI. Both amplified and restriction enzyme digested products visualized on agarose gel electrophoresis. RESULTS: All 61 molluscum cases (100%) included in the study contained MCV genetic material as demonstrated by the presence of 393- and 575-bp-long PCR amplified products. Restriction enzyme BamHI digestion of the 575-bp-long amplicon indicated that the infecting subtype in all the cases (100%) was MCV subtype I. CONCLUSIONS: Results of this study demonstrate that subtype I is the only infecting strain dominant in our region. Because the only consecutive molluscum patients admitted to our hospital were included in the study, our data do not rule out the possibility that other genotypes might be present in the Turkish population. However, it is not unreasonable to conclude that similar trends exist in the rest of the country. Results also show that a molecular-based diagnostic assay would be feasible in cases where diagnosis was deemed necessary.

Adolescent↗
PubMed2006

Paradoxically developed optochiasmatic tuberculoma and tuberculous lymphadenitis: a case report with 18-month follow up by MRI.

We report the first case ofextracranial tuberculous lymphadenitis which paradoxically developed during treatment of intracranial tuberculoma. Our patient, a 15-year-old girl who initially presented with meningitis and intracranial tuberculomas, developed extracranial tuberculomas during treatment for central nervous system tuberculosis. She was followed clinically with cerebrospinal fluid (CSF) studies and magnetic resonance imaging (MRI) at three monthly intervals. Within 18 months of specific antituberculous treatment, the patient had fully recovered. The course and response to therapy are discussed in light of the current literature.

Adolescent↗
PubMed2006

Crimean-Congo hemorrhagic fever virus: genetic analysis and tick survey in Turkey.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus in the family Bunyaviridae, genus Nairovirus. The virus is transmitted to humans through infected tick bites or from direct contact with viremic animals or humans. In the present study, a total of 1,015 adult ticks were collected from cattle (603 specimens), sheep (17 specimens), and goats (395 specimens) in the Kelkit Valley in Turkey. Four tick species were recognized on the animals in the surveyed region. The most abundant species were Rhipicephalus bursa and Hyalomma marginatum marginatum, at 47.68% (484/1,015) and 46.40% (471/1,015), respectively. Reverse transcriptase PCR was used to recover partial sequences of the CCHFV small (S) genome segment. The presence of CCHFV was determined in 3 of 33 (9.09%) R. bursa pools and in 1 of 31 (3.22%) H. m. marginatum pools. Virus sequences from R. bursa were extremely different from those of the Greek CCHFV strain (U04958) isolated from an R. bursa tick. Phylogenetic analysis indicated that the CCHFV isolates obtained in this study clustered in group 5, whose range encompasses southwestern Russian and Kosovo. This is the first evidence of CCHFV in ticks from Turkey. Even though Hyalomma is the main vector for CCHFV, R. bursa may play a role in CCHFV transmission.

Animals↗
PubMed2006

[Expression of the cathepsin L1 gene of Fasciola hepatica eucaryotic cells].

The parasitic trematode Fasciola hepatica is the causative agent of fasciolosis that is common in ruminants especially sheep and cattle and is occasionally found in humans. Fasciolosis has a worldwide distribution including Turkey and causes major economic losses in agricultural industry. Cathepsin L1 is one of the major molecules in the excretory-secretory products of F. hepatica and is involved in tissue penetration, immune evasion and feeding and therefore may be used in vaccination and serological diagnosis. The aim of this study was to evaluate cloning and expression of the cathepsin L1 gene of F. hepatica eucaryotic cells. For this purpose, total RNA was extracted from adult F. hepatica. Cathepsin L1 DNA amplicons were obtained with the reverse transcription polymerase chain reaction (RT-PCR). The 981 base-coding gene region of cathepsin L1 was amplified using specific primers to the cathepsin L1 gene. Then, the cathepsin L1 gene was cloned into the pCI-neo mammalian expression vector. The presence of the cathepsin L1 gene was confirmed by PCR screening and enzyme digestion assays. So, the resulting recombinant plasmid was named pFhCL1. Afterwards, the pFhCL1 vector was transiently transfected into Vero cells. The presence of the cathepsin L1 proteins was shown by Western immunoblotting.

Animals↗
PubMed2005

A case of brucella spondylodiscitis with extended, multiple-level involvement.

Brucellosis is a zoonosis that affects several organs and has a protean presentation. The authors report the case of a 61-year-old male patient with brucellar spondylodiscitis involving several vertebrae and a paravertebral abscess localized in the erector spinae muscle. Diagnosis was made by positive blood culture and MRI. No relapse was seen with a combined treatment (doxycycline/rifampin) for 3 months, followed by doxycycline alone for 6 months. Almost all radiologic findings disappeared at the end of a 1-year follow-up without any further treatment.

Abscess↗
PubMed2005

Serum neopterin levels in patients with chronic hepatitis B.

The aim of this study was to determine the neopterin levels and peripheral blood lymphocyte subgroups in HBeAg-positive and -negative chronic hepatitis B patients. A total of 89 patients were included in the study. The mean serum neopterin level of patients with chronic hepatitis B was significantly higher than that of the control group. In HBeAg-positive chronic hepatitis B patients, the mean serum neopterin level was significantly higher than that of anti-HBeAb-positive patients. There was no significant correlation between the serum neopterin levels and alanine aminotransferase and HBV-DNA levels in HBeAg-positive chronic hepatitis B patients. There were no significant differences between the control subjects and patients with HBeAg-positive or anti-HBeAb-positive hepatitis in terms of the percentage of peripheral blood CD4+ or CD8+ or the ratio of CD4+/CD8+ lymphocytes. Our results suggest an association between elevated neopterin concentrations and HBeAg-positivity in patients with chronic hepatitis B. However, there appears to be no association between the neopterin levels and either hepatocyte damage or viral replication status.

Adolescent↗
PubMed2005

Prevalence and genotypic distribution of hepatitis GB-C/HG and TT viruses in blood donors, mentally retarded children and four groups of patients in eastern Anatolia, Turkey.

We investigated the prevalence and genotypic distribution of GB virus-C/hepatitis G virus (GBV-C/HGV) and TT virus (TTV) in blood donors, mentally retarded children and four groups of patients living in Eastern Anatolia, Turkey. The prevalence and genetic analysis of TTV were determined by using the primers of the UTR and ORF1 regions of TTV, respectively. Reverse transcription nested (RT-n)-PCR was used to amplify 5' UTR of GBV-C/HGV. Genotyping of HGV was carried out by PCR-based genotyping assay while RFLP was conducted to determine the genotypes of TTV. TTV DNA was detected in 118 of 410 sera tested, giving an overall prevalence of 28.7%; GBV-C/HGV-RNA was detected in only 17 cases, giving an overall prevalence of 4.1%. No significant differences were observed in the number of positive or negative tests for GBV-C/HGV and TTV according to duration of illness or mean duration of institutionalization in any of the groups studied. Although all samples from the study population belonged to genotypes 1 and 4, the most common TTV genotype is G2. In conclusion, our results indicate a low endemicity of GBV-C/HGV and TTV infection in Eastern Anatolia, Turkey. The presence of G2 strains reveals the limited genetic diversity of the GBV-C/HGV circulating in Turkey. We suggest that TTV infection of genotypes 1 and 4 is prevalent in the same region.

Adolescent↗
PubMed2005

Toxocariasis seroprevalence in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory disease for which immunogenetic susceptibility factors have been defined. The aim of this study was to investigate seroprevalence of Toxocara canis (T. canis) in patients with RA. Forty-five patients with RA who were all diagnosed according to the ACR criteria and 48 health controls were included in this study. The mean age of patients with RA and of controls was 50+/-14 and 49+/-13, respectively. In both groups T. canis IgG antibodies were investigated with ELISA. Toxocara canis seroprevalence in patients with RA (35.6%) was significantly higher than that in the control group (8.3%) (p=0.001). There was no significant difference between patients with RA and control group in terms of behavioral factors (except in frequency of hand washing), demographic and socio-economic factors, while there was a difference in terms of owning dogs and cats or in the duration of ownership. When the patients with RA were divided into seropositive and seronegative, there were no significant differences between both groups in terms of demographic factors, socio-economic factors, behavioral factors, owning dogs and cats or duration of ownership and active or remission state of the illness, duration of disease and disability level in patients with RA (p > 0.05). In view of the present results, it is suggested that Toxocara infection was acquired before RA had developed and that high seroprevalence may result from exposure to pets and soil. It seems that this subject requires further investigations with larger numbers of samples in order to fully evaluate the causes of high seropositivity.

Journal Article↗
PubMed2004

The frequency of Toxocara infection in mental retarded children.

Human toxocariasis is commonly seen in places where stray and Toxocara canis-infected dog population is high. There is a strong correlation between frequency of Toxocara infection, life style, and infection risk. Institutionalization of mental retarded patients increases to risk of toxocariasis. In this study, we aimed at investigating the frequency of Toxocara infection among children with mental retardation not requiring institutionalization. The study included 96 cases, who had educatable mental retardation and 85 healthy subjects who comprised the control group. Anti-Toxocara IgG or IgM antibodies were investigated in all serum samples, using ELISA method. The frequency of Toxocara infection was found significantly higher in mental retarded cases than in those in the control group (18.8% and 7.1% respectively) (p < 0.05). There was no significant difference between mental retarded children and the control group in terms of mean age, age groups, gender, owning dogs and cats and duration of their ownership, socio-economic level and behavioural factors, and personal hygiene (p > 0.05). We did not find any significant difference between Toxocara seropositive and seronegative mental retarded children in terms of demographic factors and epidemiological factors that could increase the risk of Toxocara infection (p > 0.05). The present study is the first seroprevalence study carried out with a mental retarded group not requiring institutionalization. Determination of high frequency of Toxocara infection suggests that these subjects constitute a risk factor for Toxocara infection, which may be attributed to their behavioural patterns.

Adolescent↗
PubMed2004

Hepatocyte growth factor (HGF) in patients with acute brucellosis.

In this prospective study, we investigated the serum levels of hepatocyte growth factor (HGF) and C-reactive protein (CRP) before and after the treatment of patients with acute brucellosis. The study comprised 58 patients with acute brucellosis and 30 healthy volunteers. Pre-treatment serum HGF levels of 58 patients with acute brucellosis (1548.6 +/- 220.1) were significantly higher than levels of the control group (401.4 +/- 69.7) (p < 0.001). Serum levels of HGF and CRP significantly decreased at the end of the treatment period (p < 0.001). Post treatment, levels did not differ from those of the control group (p > 0.05). Serum HGF levels of patients with acute brucellosis correlated to CRP and ALT levels (r: 0.922, 0.752; p < 0.001, respectively). Our findings suggest that serum HGF levels may be used as a supplementary marker to evaluate the effectiveness of the treatment in patients with acute brucellosis.

Acute Disease↗
PubMed2004

A case of mumps conjunctivitis: detection of the virus RNA by nested PCR in tear sample.

Mumps is a disease caused by a virus that can infect many parts of the body, especially the parotid salivary glands. A case of epidemic parotitis in an adult female affected by bilateral conjunctivitis is presented. Mumps virus was detected in tear samples by reverse transcription nested polymerase chain reaction (RT-n-PCR). The conjunctivitis resolved completely within 11 d.

Adult↗
PubMed2004

Role of L-carnitine in the prevention of acute liver damage induced by carbon tetrachloride in rats.

BACKGROUND AND AIM: Lipid peroxidation is the most important mechanism in the pathogenesis of acute liver damage with carbon tetrachloride (CCl4). L-carnitine may prevent lipid peroxidation and thus may protect against liver damage. In the present study we investigated the protective effect of L-carnitine in experimental acute liver damage induced by CCl4. METHODS: Fifty rats were allocated to five equal groups. The first group was the control (group 1), the second group received an intraperitoneal CCl4 injection for 3 days (group 2), and the third group received a 50 mg/kg subcutaneous L-carnitine injection for 4 days, beginning a day before CCl4 injection. The CCl4 injection was continued for 3 days in the concerned group (group 3). Group 4 was given a CCl4 injection for 7 days and group 5 received a 50 mg/kg subcutaneous L-carnitine injection for 8 days, beginning a day before CCl4 injection. This group continued to receive a CCl4 injection for 7 days. Rats in groups 2 and 3 were killed on the fifth day. Rats in groups 1, 4 and 5 were killed on the ninth day. Plasma and liver tissue malondialdehyde (MDA) levels, glutathione peroxidase (GSH-Px) activity and liver enzyme levels were studied. Histopathological investigations were conducted. RESULTS: Liver tissue MDA levels decreased significantly in group 3 compared to group 2 (P<0.001). Liver tissue MDA levels in group 5 decreased significantly in comparison to those of group 4 (P<0.001). Liver tissue GSH-Px activity in group 5 was significantly lower than that in group 4 (P<0.05). There were no significant differences between groups 3 and 4 regarding GSH-Px activity (P>0.05). Steatosis, inflammation and necrosis in group 3 were significantly reduced when compared to group 2 (P<0.01). Fibrosis development was not identified in groups 2 and 3. Steatosis in group 5 was significantly lower than that in group 4 (P<0.05) and there were no significant differences between groups 4 and 5 with regards to inflammation and necrosis (P>0.05). Mild fibrosis development was identified in groups 4 and 5 but the difference between the groups was not significant. CONCLUSION: It appears that L-carnitine has a protective effect in the early stage of experimental acute liver damage induced by CCl4. As the toxic effect or damage continues, its effect lessens.

Acute Disease↗
PubMed2003

Serum cytokine levels in patients with acute brucellosis and their relation to the traditional inflammatory markers.

The number of clinical studies on gamma interferon (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) in human brucellosis is limited. The present study was focused on IFN-gamma, TNF-alpha and IL-4 levels in acute brucellosis cases, in the acute phase and at the end of the treatment. The relation of these cytokines to traditional inflammation markers was also investigated. The study included 27 cases of acute brucellosis and 20 healthy volunteers who had no complaints. It was found that mean IFN-gamma and TNF-alpha levels, CRP (C-reactive protein) levels and ESR (erythrocyte sedimentation rate) values were significantly higher in acute brucellosis cases as compared to post-treatment values and values measured in the control group. In addition, IFN-gamma and TNF-alpha levels measured in the acute phase correlated with the increase in CRP levels and ESR values. Our results confirmed that IFN-gamma and TNF-alpha are involved in the pathophysiology of brucellosis and are closely related to the inflammatory activation of the disease. In view of the present findings, it is suggested that IFN-gamma and TNFalpha may be used for monitoring brucellosis.

Acute Disease↗
PubMed2003

Seropositivity of Epstein-Barr virus in Eastern Anatolian Region of Turkey.

In the present study, we have investigated the seropositivity of Epstein-Barr virus (EBV) and the epidemiological factors affecting this seropositivity. A total of 540 subjects living in central Elazig Province and its surroundings were enrolled in the study. IgG antibodies against capsid antigen of EBV (anti-VCA IgG) were determined by ELISA. Seropositivity was found to be 99.4%. There was a significant relationship between increased anti-VCA IgG levels and age, living in crowded families, exposure in public places and low income (p < 0.05). However, no significant alterations in serum anti-VCA IgG antibody were observed in terms of gender, blood transfusion and educational status (p > 0.05). In conclusion, we have demonstrated the commonly presence of EBV Infections in the public and contamination with the infection at early stages of life in the Elazig region. An overpopulated family environment, low income status and living in shared accommodation facilities play important roles in acquiring EBV infection.

Adolescent↗
PubMed2002

Trace elements in viral hepatitis.

In this study, serum trace elements, including selenium (Se), zinc (Zn), copper (Cu), were determined by using Atomic Absorption Spectrophotometer (SpectrAA 250 Plus Zeeman, Varian, Australia) in sera of patients with viral hepatitis (A, B, C, D, E) cases (n = 102), and statistically compared with the controls (n = 52). In viral hepatitis, Cu levels were found as 3.23 +/- 1.02 mg/L, and this value was significantly higher than the control group (1.13 +/- 0.21) (p < 0.01). Both, Se and Zn levels found to be significantly low in viral hepatitis cases (p < 0.01). While Se level was 81.4 +/- 26.01 microg/L in viral hepatitis (n = 101), it was found to be 166.15 +/- 4.58 microg/L in healthy individuals. Meanwhile, Zn levels were 0.230 +/- 0.081 mg/L and 0.748 +/- 0.392 mg/L in hepatitis cases (n = 101) and the control group, respectively. There was no difference amongst viral hepatitis groups classified in regard with agents and clinical manifestation, such as A, acute hepatitis B, chronic hepatitis B, C, D and E. Previously, it was indicated that absorption disorders in gastrointestinal system, especially in chronic cases, were not main causes of decrease of trace elements by iron and several other parameters in sera of the cases. Therefore, we suggest that decrease in Zn and Se levels and elevation in Cu levels are probably resulted from defence strategies of organism and induced by the hormone-like substances.

Analysis of Variance↗
PubMedDate not supplied

Prevalence and genotypes of hepatitis G virus among hemodialysis patients in Eastern Anatolia, Turkey.

OBJECTIVES: To study the prevalence and genotype distribution of hepatitis G virus (HGV) in hemodialysis patients in East Anatolia, Turkey. SUBJECTS AND MATERIALS: Eighty-nine hemodialysis patients and 30 healthy individuals were analyzed by using reverse-transcriptase nested polymerase chain reaction with primers specific for 5' untranslated region. HGV genotyping was performed by PCR and three randomly selected HGV-positive samples were sequenced. RESULTS: Of the 89 hemodialysis patients, HGV RNA was detected in 9 (10.2%). All of our isolates were assigned to genotype 2. CONCLUSION: Our results showed that hemodialysis patients carry the risk for HGV infection in East Anatolia, Turkey.

Adult↗
PubMedDate not supplied

Investigation of Epstein-Barr virus DNA in formalin-fixed and paraffin- embedded breast cancer tissues.

OBJECTIVE: To investigate etiological role of Epstein-Barr virus (EBV) DNA in breast cancer. MATERIALS AND METHODS: The presence of EBV DNA in 57 breast cancer tissues was investigated with a sensitive PCR assay. The breast cancer tissues were from invasive ductular (n=28), lobular (n=20) and other miscellaneous carcinomas (n=9). Tissues from normal breasts and patients with various benign breast diseases (n=55): fibrocystic disease (n=34), fibroadenoma (n=16), hyperplasia, and granulomatous mastitis (n=5), were used as control samples. RESULTS: EBV DNA was detected in 13 (23%) cancerous tissues (7 ductular, 4 lobular, 2 other carcinoma) and 19 (35%) in the control tissues. The difference between EBV presence in malignant and benign tissues was not statistically significant (p>0.05). CONCLUSION: The presence of EBV DNA was detected almost equally in both breast cancer and normal tissues, which indicates no etiological role for EBV in breast cancer. We suggest further etiological studies.

Adolescent↗