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Senem Maral Muradiye Acar Ozlem Sahin Balcik Eyyup Uctepe Omer Faruk Hatipoglu Derya Akdeniz Hatice Uludag Altun Ali Kosar Mehmet Gunduz Esra Gunduz 《Medicine》2015,94(16)
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.
Esra Baltacio?lu Ferda Alev Akalin Eda Topalo?lu Erkan Süküro?lu Umit Cobano?lu 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):803-808
Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease. 相似文献
4.
OXA-14, another extended-spectrum variant of OXA-10 (PSE-2) beta-lactamase from Pseudomonas aeruginosa.
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Pseudomonas aeruginosa 455, isolated in Ankara, Turkey, produced a pI 6.2 beta-lactamase determined by plasmid pMLH53 and resisted all beta-lactams except carbapenems. This beta-lactamase, named OXA-14, corresponded to OXA-10 (PSE-2) except that aspartate replaced glycine at position 157 and thus is intermediate between OXA-10 and OXA-11, which has aspartate at position 157 and a further substitution at position 143. 相似文献
5.
A sexually dimorphic ratio of orbitofrontal to amygdala volume is altered in schizophrenia. 总被引:3,自引:0,他引:3
Raquel E Gur Christian Kohler Bruce I Turetsky Steven J Siegel Stephen J Kanes Warren B Bilker Avis R Brennan Ruben C Gur 《Neuropsychopharmacology》2004,55(5):512-517
BACKGROUND: Neuroanatomic sexual dimorphisms have been correlated with behavioral differences between healthy men and women. We have reported higher orbitofrontal cortex to amygdala ratio (OAR) in women than men. Although gender differences in schizophrenia are evident clinically and correlate with neuroanatomic measures, their relationship to OAR has not been examined. METHODS: Magnetic resonance imaging was performed in 31 neuroleptic-na?ve schizophrenic patients (16 men) and 80 healthy volunteers (34 men), aged less than 50 years. An automated tissue segmentation procedure was combined with expert-guided parcellation of orbitofrontal and amygdala volumes. RESULTS: Men with schizophrenia had increased OAR relative to healthy men, whereas women had decreased OAR. Increased OAR in men with schizophrenia reflected abnormally low amygdala volumes, whereas decreased OAR in women reflected abnormally low orbitofrontal volumes. Less severe negative symptoms were associated with increased OAR in men but with decreased OAR in women. In men, increased amygdala volume was associated with greater symptom severity, whereas in women higher volumes of both amygdala and orbitofrontal regions were associated with lesser severity of negative symptoms. CONCLUSIONS: These opposite OAR abnormalities, whereby men show feminization and women masculinization, suggest gender-mediated effects of the underlying neuropathologic processes. The correlations with symptom severity suggest that neuroanatomic abnormalities in OAR reflect compensatory brain changes. 相似文献
6.
M. Chanimov M. L. Cohen Y. Grinspun M. Herbert R. Reif I. Kaufman & M. Bahar 《Anaesthesia》1997,52(3):223-228
We have previously demonstrated in a rat model that the lumbar intrathecal injection of 0.02 ml 6.3% magnesium sulphate, a concentration iso-osmolar with rat plasma, produces a state of spinal anaesthesia and general sedation which reversed completely after 6 h, without evidence of neurotoxicity, immediately or during the week thereafter. Using the same model and five groups of six animals in each, we administered the same volume and concentration of magnesium sulphate and compared its clinical effects with those of 0.02 ml 12.6% magnesium sulphate, 0.02 ml 2% lignocaine and 0.02 ml 0.9% sodium chloride solution, given as a series of 15 injections on alternate days for a period of 1 month. The animals were then killed and their spinal cords and meninges examined histologically. No significant differences were noted in the times of onset, durations of sensory and motor blockade and the times to full recovery throughout the entire period of 1 month's observation in the animals receiving intrathecal 6.3% magnesium sulphate. In the group receiving 12.6% magnesium sulphate, the time of onset of sensory and motor blockade was shorter and the duration of both parameters was significantly longer than in the former group. Full clinical recovery and resumption of normal eating and drinking took place in both groups throughout the entire series of 15 successive intrathecal injections. Identical, mild, uniform histopathological changes in the spinal cord were seen in all the five groups, including the group in which only the intrathecal catheter was implanted. The complete recovery and benign consequences of repeated intrathecal injections of iso-osmolar magnesium sulphate in a rat model indicate a lack of neurotoxicity and provide an impetus for further trials in larger animal species, before initial clinical trials of this substance, given intrathecally, in humans. 相似文献
7.
8.
It is well established that visual display unit (VDU) operators complain of visual fatigue and visual stress during after-work hours. The present study was divided into two parts. In the first part, standard eye examinations were performed on a group of VDU workers (n = 32) and a control group (n = 15); those subjects who were found to have correct vision (n = 16 and 13, respectively) participated in the second part. The eye examinations revealed that on the average, the VDU workers suffered more than twice as many visual impairments as the controls. In those with correct vision, the near point of accommodation was measured at the beginning of the workday at the start of the week, and at the end of the workday, four days later. In the VDU group, the decrease in accommodation was uniformally distributed between zero and 1.0 diopter, whereas among the non-VDU workers, 77% of the decrease was between zero and 0.25 diopter. The dynamic range of accommodation in the VDU workers on the second examination was smaller than on the first. We conclude that some of the visual stress and visual fatigue that developed at work hindered visual activities after work. 相似文献
9.
Hakan Gundes Bilgehan Tosun Sibel Gundes Alptekin Tosun Bahar Muezzinoglu 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(2):193-197
It is a common algorithm for hand surgeons to diagnose and treat persistent post-traumatic wrist pain as complex regional pain syndrome (CRPS). Although it works for many patients, some conditions that affect the wrist don’t fall in this category and worsen with this treatment practice. We present a single-handed patient who had had a non-displaced distal radius fracture and was treated as CRPS for the next three months. He was eventually diagnosed with late tuberculous tenosynovitis of the wrist and a total wrist arthrodesis was performed. We believe that Mycobacterium tuberculosis infection should be in the differential diagnosis of persistent post-traumatic joint pain. This is especially important as Mycobacterium infections are becoming more common due to an increase in patients with chronic immunosuppression and definitive diagnosis and treatment of tuberculous tenosynovitis needs a high index of clinical suspicion. 相似文献
10.
Ozgur O; Boyacioglu S; Ozdogan M; Gur G; Telatar H; Haberal M 《Nephrology, dialysis, transplantation》1997,12(2):289-291
Background. It is known that Helicobacter
pylori (Hp) plays an important role in gastritis and peptic
ulcer disease in the general population. Although dyspeptic complaints are
frequent in haemodialysis (HD) patients and renal transplant recipients,
there are few reports regarding the prevalence of Hp and its possible
effects on this group of patients. This study was performed to examine the
prevalence of Hp infection in patients on regular HD treatment and to
detect its role in the pathogenesis of dyspepsia in this group of patients.
Methods. Two hundred and one patients with dyspeptic
complaints were included in the study. The groups consisted of 47 HD, 54
renal transplant recipients, and 100 non-renal disease patients. Upper
gastrointestinal endoscopies were performed and gastric antral biopsies
were obtained for urease test in all patients.
Results. Twenty-eight (60%) of the 47 HD and 28 (70%)
of the 54 RTR were positive for Hp. Sixty-four (64%) of the 100 patients
with various gastrointestinal complaints and known to have no renal
dysfunction were positive for Hp. The Hp prevalences among the three groups
were not significantly different (P <0.05). The prevalence of Hp
infection did not correlate with the haemodialysis duration nor the
post-transplantation duration (P <0.05). There was no correlation
between the prevalence of Hp infection and duration of haemodialysis
therapy or time post-transplantation. Conclusion.
These findings suggest that HD patients are not protected against Hp
infection as the Hp prevalences are as high as that for the non-renal
disease group. The increased dyspeptic complaints may be partly related to
Hp infection. 相似文献