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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   
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Iron overload presenting as exacerbation of hepatic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation has not been previously described. We report 6 patients with established hepatic GVHD in whom iron overload (median serum ferritin, 7231 mug/dL; median transferrin saturation, 77%) resulting from a lifetime median of 20 units of packed red blood cell transfusions was manifested by worsening of liver function. Liver biopsies performed in 4 patients confirmed severe iron overload and also hepatic GVHD. Analysis for the C282Y and H63D hemochromatosis gene mutation was negative for the homozygous state in all 6 patients. Erythropoietin-assisted phlebotomy resulted in normalization of liver function at a median of 7 months and of serum ferritin at a median of 11 months. Immunosuppressive therapy was successfully tapered in all 4 patients who completed the phlebotomy program, and this supported the impression that iron overload, rather than GVHD, was the principal cause of liver dysfunction. At a median follow-up of 50 months (range, 18-76 months) from the transplantation and 25 months (range, 5-36 months) from ferritin normalization, all 4 patients require maintenance phlebotomy. We conclude that iron overload can mimic GVHD exacerbation, thus resulting in unnecessary continuation or intensification of immunosuppressive therapy for GVHD, and that maintenance phlebotomy is necessary after successful iron-reduction therapy.  相似文献   
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Adrenergic signalling between rat taste receptor cells   总被引:2,自引:0,他引:2  
In taste buds, synaptic transmission is traditionally thought to occur from taste receptor cells to the afferent nerve. This communication reports the novel observation that taste receptor cells respond to adrenergic stimulation. Noradrenaline application inhibited outward potassium currents in a dose-dependent manner. This inhibition was mimicked by the β agonist isoproterenol and blocked by the β antagonist propranolol. The α agonists clonidine and phenylephrine both inhibited the potassium currents and elevated intracellular calcium levels. Inwardly rectifying potassium currents were unaffected by adrenergic stimulation. Experiments using the RT-PCR technique demonstrate that lingual epithelium expresses multiple α (α1a, α1b, α1c, α1d, α2a, α2b, α2c) and β (β1, β2) subtypes of adrenergic receptors, and immunocytochemistry localized noradrenaline to a subset of taste receptor cells. Collectively, these data imply strongly that adrenergic transmission within the taste bud may play a paracrine role in taste physiology.  相似文献   
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The lumbrical muscles are located in the midpalm, dorsal to the palmar aponeurosis. The main function of these muscles is an indirect contribution to interphalangeal joint extension by decreasing the flexor effect of the flexor digitorum profundus muscle. Due to their minor biomechanical functions and suitable constructions, these muscles have been preferred in reconstructive surgery as local transposition flaps or pedicled flaps. Despite the surgical and clinical importance, vascular anatomical studies of these muscles are not well represented in the current literature. This study was performed in the Department of Anatomy of the Faculty of Medicine of the Ege University. Thirty-four cadaver hands, injected with red-coloured latex were used, and we aimed to describe the morphometry and vascular anatomy of the lumbrical muscles. We measured the length and width of the muscles, after removing their epimisium, and the diameter and length of the arteries to the muscles. The outcomes of our study determined that the length and width of the lumbrical muscles were reduced significantly from radial towards ulnar sides. The lumbrical muscles were supplied from both their palmar and dorsal surfaces by both superficial and deep palmar arches and/or their branches. We also described the level of entry of the dominant arteries for each lumbrical muscle and measured the size of the vessels and muscles to guide some surgical approaches. This anatomical study could guide for some surgical approaches and reduce the deficiency about the vascular anatomical patterns of the lumbrical muscles in the literature.  相似文献   
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The combination therapies recommended by the World Health Organization for treatment of brucellosis are doxycycline plus rifampicin or doxycycline plus streptomycin. Although highly successful results have been obtained with these two regimens, relapse rates as high as 14.4%. The most effective and the least toxic chemotherapy for human brucellosis is still undetermined. The aim of the present study was to investigate the efficacy, adverse effects and cost of ofloxacin plus rifampicin therapy, and doxycycline plus rifampicin therapy and evaluate in the treatment of brucellosis.  相似文献   
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Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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