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Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
3.
A 47-year-old woman presented with a left-sided watery nasal discharge persisting for 3 weeks after an orthopedic operation using spinal anesthesia. The testing of the nasal fluid for β-2 transferrin confirmed that the leakage was cerebrospinal fluid (CSF). The computed tomographic cisternography revealed a left-sided bone defect in the cribriform plate. Endonasal approach was performed for closing the defect. At 3-month follow-up, CSF rhinorrhea had not recurred. In this report, we present an unexpected CSF rhinorrhea after a spinal anesthesia and discuss the reason of spontaneous leak after spinal anesthesia, as well as discuss current diagnosis and management of CSF rhinorrhea with the composite graft.  相似文献   
4.

Introduction

Biocompatibility of pulp capping materials is important for successful use in dentistry. These materials should be nontoxic and permissive for proliferation and induction of odontogenic differentiation of pulp cells. The aim of our study was to evaluate the effects of enamel matrix derivative (EMD), mineral trioxide aggregate (MTA), and calcium hydroxide-containing cement (DYCAL) on proliferation and odontogenic differentiation of human tooth germ stem cells (hTGSCs) in which cells belonging to both pulp tissue and dental follicle exist.

Methods

The 96-well plates, 24-well plates, and special chamber slides were coated with biomaterials for cell proliferation, differentiation, and scanning electron microscopy analysis. Odontogenic differentiation of hTGSCs was evaluated by analyzing mRNA expression of dentin sialophosphoprotein (DSPP) by real-time polymerase chain reaction expression analysis, measurement of alkaline phosphatase activity, and visualization of calcium depositions by von Kossa staining.

Results

Our results demonstrate that EMD is the best material in terms of inducing differentiation and proliferation of hTGSCs. DYCAL was found to be toxic to hTGSCs; however, EMD-coated DYCAL showed less toxicity. EMD-coated MTA was not efficient at inducing proliferation and differentiation.

Conclusions

Pulp capping materials come in direct contact with dental pulp cells; thus, they require comprehensive evaluation of interactions between cells and biomaterials. Therefore, we cultured hTGSCs, capable of odontogenic differentiation, on pulp capping materials directly. Our results suggest that combination of capping materials with EMD would increase the quality of capping by increasing biocompatibility of capping materials.  相似文献   
5.
Abstract – Thirty‐five (case 1), 15 (case 2) and 22 (case 3)‐year‐old female patients presented to Yeditepe University Dental Faculty Clinic because of esthetic reasons. Fractures of maxillar central incisors including enamel and dentin were diagnosed. Beveling with diamond bur was performed in all four cases. Dentin was cleaned with tungsten carbid bur. The teeth were etched with 37% phosphoric acid, restored with an adhesive system and microhybrid composite. Finishing and polishing procedures were performed by discs (Sof‐Lex) and burs. Restorations were found successful according to modified United States Public Health Service (USPHS) criteria after 2 years in terms of retention, color match, marginal discoloration, secondary caries, marginal adaptation, and surface texture.  相似文献   
6.

Background:

Rate of coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) varies in different countries. This may be attributable to common transmission routes as well as social, economic, and cultural factors.

Objectives:

The purpose of this study was to investigate the prevalence and risk factors of HCV infection among HIV-positive patients in Istanbul, Turkey.

Patients and Methods:

Since January 2006 to November 2013, 949 HIV-positive patients that were enrolled in this study by ACTHIV-IST (Action Against HIV in Istanbul) Study Group, which consists of five centers to follow up HIV-positive patients in Istanbul. Epidemiologic and clinical data were collected retrospectively from medical records and were transferred to an HIV database system.

Results:

Among 949 patients, 84% were men and the mean age was 37.92 ± 11.54 years (range, 17-79). The most frequent route of transmission was heterosexual intercourse (48.8%), followed by men having sex with men (30.5%). Only nine patients (0.9%) had history of injection drug use (IDU). The prevalence of HIV/HCV coinfection was 0.9% (9:949). The IDU rate was 44.4% (4:9) in patients with HIV/HCV coinfection (three of them were not Turkish citizens), whereas this rate was only 0.6% (5:881) in patients with only HIV infection (P < 0.01). Genotypes 1b, 2a/2c, and 3 were determined in five, one, and two patients, respectively. Genotype could not be determined in one patient. History of residence in a foreign country (P < 0.01) and imprisonment (P < 0.01) were also considered as risk factors in terms of HIV/HCV coinfection.

Conclusions:

Prevalence of HIV/HCV coinfection is considerably low in Turkey. The extremely rare prevalence of IDU might have a role in this low prevalence.  相似文献   
7.
Grayanotoxin is a naturally occurring sodium channel toxin which enters the human food supply by honey made from the pollen and nectar of the plant family Ericaceae in which rhododendron is a genus. Grayanotoxin/mad honey poisoning is a little known, but well studied, cholinergic toxidrome resulting in incapacitating and, sometimes, life-threatening bradycardia, hypotension, and altered mental status. Complete heart blocks occur in a significant fraction of patients. Asystole has been reported. Treatment with saline infusion and atropine alone is almost always successful. A pooled analysis of the dysrhythmias occurring in 69 patients from 11 different studies and reports is presented. The pathophysiology, signs, symptoms, clinical course, and treatment of grayanotoxin/mad honey poisoning are discussed. In the nineteenth century grayanotoxin/mad honey poisoning was reported in Europe and North America. Currently, documented poisoning from locally produced honey in Europe or North America would be reportable. Possible reasons for this epidemiologic change are discussed.  相似文献   
8.

Background

Polycystic ovary syndrome (PCOS) is related to metabolic syndrome, insulin resistance, and cardiovascular metabolic syndromes. This is particularly true for individuals with central and abdominal obesity because visceral abdominal adipose tissue (VAAT) and epicardial adipose tissue (EAT) produce a large number of proinflammatory and proatherogenic cytokines. The present study aimed to determine whether there are changes in VAAT and EAT levels which were considered as indirect predictors for subclinical atherosclerosis in lean patients with PCOS.

Methods

The clinical and demographic characteristics of 35 patients with PCOS and 38 healthy control subjects were recorded for the present study. Additionally, the serum levels of various biochemical parameters were measured and EAT levels were assessed using 2D-transthoracic echocardiography.

Results

There were no significant differences in mean age (p?=?0.056) or mean body mass index (BMI) (p?=?0.446) between the patient and control groups. However, the body fat percentage, waist-to-hip ratio, amount of abdominal subcutaneous adipose tissue, and VAAT thickness were higher in the PCOS patient group than in the control group. The amounts of EAT in the patient and control groups were similar (p?=?0.384). EAT was correlated with BMI, fat mass, waist circumference, and hip circumference but not with any biochemical metabolic parameters including the homeostasis model assessment of insulin resistance index or the levels of triglycerides, low-density lipoprotein cholesterol, and high-density lipoprotein (HDL) cholesterol. However, there was a small positive correlation between the amounts of VAAT and EAT. VAAT was directly correlated with body fat parameters such as BMI, fat mass, and abdominal subcutaneous adipose thickness and inversely correlated with the HDL cholesterol level.

Conclusions

The present study found that increased abdominal adipose tissue in patients with PCOS was associated with atherosclerosis. Additionally, EAT may aid in the determination of the risk of atherosclerosis in patients with PCOS because it is easily measured.
  相似文献   
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10.
Tourette syndrome (TS) is a childhood onset neurologic disorder with manifestations including multiple motor and phonic tics, and in most cases a variety of behavioral comorbidities such as attention deficit hyperactivity disorder, obsessive compulsive disorder, and other impulse control disorders. Although it is considered a hereditary disorder, likely modified by environmental factors, genetic studies have yet to uncover relevant causative genes and there is no animal model that mimics the broad clinical phenomenology of TS. There has been a marked increase in the number of neurophysiological, neuroimaging, and other studies on TS. The findings from these studies, however, have been difficult to interpret because of small sample sizes, variability of symptoms across patients, and comorbidities. Although anti-dopaminergic drugs are the most widely used medications in the treatment of TS, there has been increasing interest in other drugs, behavioral therapies, and surgical approaches including deep brain stimulation. Herein, we review the current literature and discuss the complexities of TS and the challenges in understanding its pathophysiology and in selecting the most appropriate treatment. We also offer an expert’s view of where the field of TS may be headed.  相似文献   
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