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1.
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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The in vivo effects of non-steroidal anti-inflammatory drugs (NSAIDs) on the host immune system are still poorly understood. However, through inhibition of prostaglandin synthesis, NSAIDs may exhibit immunomodulating properties. The present work was aimed at evaluating the influence of niflumic acid on immune responses when administered orally for 7 consecutive days to 8-week-old inbred mice. Immunological tests were performed 24 h after the arrest of the treatment. At a dosage of 50 mg/kg/day, niflumic acid exerted noticeable immunostimulating effects, as shown by an increase in plaque-forming cell numbers after in vivo immunization with sheep red blood cells, an augmentation of spleen cell proliferation responses to stimulation with T- or B-cell mitogens and of T-cell cytotoxic response to allogenic cells. Phagocytosis-induced chemiluminescence of peritoneal macrophages was also enhanced whereas interleukin-1 production by these cells was depressed, but without concomitant modification in interleukin-2 production by T-cells. Increasing the niflumic acid dosage to 75 mg/kg resulted in the disappearance of the immunostimulatory effects on lymphocytes responses. Macrophage activities were affected similarly in mice receiving 50 mg/kg. These results demonstrate that niflumic acid is able to stimulate in vivo several immunological functions and, consequently, to maintain host immune defenses. Interestingly, it depressed interleukin-1 production, known to play a major role in the inflammatory process.  相似文献   
3.
Whether a flap can be raised successfully in a body region that has been subjected to burn injury remains an issue. The aim of this study was to investigate the survival of skin flaps that were elevated after superficial and deep partial-thickness burn injury in a rat model. Sixty-five rats were divided into five groups: Group 1 (N = 15) was the control group, group 2 (N = 10) included rats with superficial partial-thickness burns that had flaps elevated on day 0, group 3 (N = 15) was comprised up of rats with superficial partial-thickness burns that had flaps elevated on day 4, group 4 (N = 10) included rats with deep partial-thickness burns that had flaps elevated on day 0, and group 5 (N = 15) was comprised of rats with deep partial-thickness burns that had flaps elevated on day 4. Caudally based dorsal flaps consisting of skin and panniculus carnosus were elevated in all groups, and the amount of surviving tissue on each flap was quantified. The surviving areas of flaps elevated on postburn days 0 and 4 in superficial partial-thickness burn zones (groups 2 and 3) were larger than those of flaps that were elevated on postburn days 0 and 4 in deep partial-thickness burn zones (groups 4 and 5). The surviving portions of flaps that were elevated on day 4 in superficial partial-thickness burn zones (group 3) were similar to the surviving areas of flaps in the control group (group 1), and were larger than those of all other groups (groups 2, 4, and 5). In this rat model, flaps were elevated in superficial dermal burn zones with successful outcomes. However, raising flaps in deep dermal burn zones was not a reliable method.  相似文献   
4.
The fingertip is an extremely intricate area of digital sensibility that plays an important role in fine perception and hand function. Thus, sensate fingertip reconstruction is essential to the recovery of most hand functions. The authors used two methods of direct-flow homodigital neurovascular island flap coverage to reconstruct distal finger amputations-namely, the triangular-advancement flap technique and the step-advancement flap method. The authors present their experience with these two variations of direct-flow homodigital neurovascular island flaps and their use in reconstructing 18 fingertips and 7 proximal amputation stumps. They did not observe flap failure, and they achieved stable, well-vascularized, appropriate-thickness skin coverage with good sensory properties in all patients. However, they found that the triangular-advancement flap technique was easier to plan and perform than the step-advancement method.  相似文献   
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BACKGROUND: Intermittent interleukin-2 (IL-2) therapy leads to a sustained increase of CD4 T cells in HIV-1-infected patients. METHODS: Symptom-free HIV-1-infected patients who were naive to all antiretroviral drugs (n = 68) and/or to protease inhibitors (n = 50) and had a CD4 cell count of 200-550 x 10(6) cells/l were randomly assigned to start lamivudine/stavudine/indinavir alone (controls) or combined from week 4 with subcutaneous IL-2 (5 x 10(6) IU twice daily for 5 days: every 4 weeks for three cycles, then every 8 weeks for seven cycles). Immunological and virological results were monitored until week 74. RESULTS: CD4 T cell counts increased more in the IL-2 group than in the controls (median increases 865 and 262 x 10(6) cells/l, respectively; P < 0.0001); an 80% increase in CD4 T cells was achieving by 89% of the IL-2 group and by 47% of the controls (P < 0.0001). Decrease of plasma viral loads was similar in both groups. Compared with controls, IL-2 induced a greater increase of naive and memory CD4 T cells, lymphocyte expression of CD28 and CD25 (P < 0.0001) and natural killer cells (P < 0.001). In a logistic regression analysis, odds of being responders to recall antigens was 8.5-fold higher in IL-2 recipients (P = 0.002) than in controls. The former experienced a higher level of antibody response to tetanus vaccination at week 64 than controls (32 and 8 haemagglutinating units/ml, respectively; P = 0.01). CONCLUSIONS: The combination of antiviral drugs and IL-2 induced a greater expansion and function of CD4 T cells than antiretroviral drugs alone.  相似文献   
9.
Investigations into the cellular and molecular biology of genes that cause inherited forms of Parkinson's disease, as well as the downstream pathways that they trigger, shed considerable light on our understanding the fundamental determinants of life and death in dopaminergic neurons. Homozygous deletion or missense mutation in DJ-1 results in autosomal recessively inherited Parkinson's disease, suggesting that wild-type DJ-1 has a favorable role in maintaining these neurons. Here, we show that DJ-1 protects against oxidative stress-induced cell death, but that its relatively modest ability to quench reactive oxygen species is insufficient to account for its more robust cytoprotective effect. To elucidate the mechanism of this cell-preserving function, we have screened out the death protein Daxx as a DJ-1-interacting partner. We demonstrate that wild-type DJ-1 sequesters Daxx in the nucleus, prevents it from gaining access to the cytoplasm, from binding to and activating its effector kinase apoptosis signal-regulating kinase 1, and therefore, from triggering the ensuing death pathway. All these steps are impaired by the disease-causing L166P mutant isoform of DJ-1. These findings suggest that the regulated sequestration of Daxx in the nucleus and keeping apoptosis signal-regulating kinase 1 activation in check is a critical mechanism by which DJ-1 exerts its cytoprotective function.  相似文献   
10.
OBJEctive: The oxidant-antioxidant balance plays an important role in the pathogenesis of COPD. The aim of the present study was to evaluate the effects of exercise, as an oxidative stress factor on the oxidant-antioxidant balance and to investigate whether short-term antioxidant treatment affects lipid peroxidation products. METHODOLOGY: Twenty-one stable COPD patients and 10 control subjects were included in the study. Symptom-limited exercise tests were performed by all subjects. Blood was collected before and 1 h after exercise in control subjects and before, 1 and 3 h after exercise in COPD patients, for analysis of malondialdehyde (MDA), reduced glutathione (GSH) and vitamin E (VE) levels. VE and vitamin C treatments were added to the regular bronchodilator therapy in 10 COPD patients for 1 month. After the treatment period, an exercise test was performed and blood was collected again for MDA, GSH and VE levels. RESULTS: Baseline GSH and VE levels were significantly lower in the COPD group when compared with the control subjects. There was no statistically significant difference in MDA levels between the two groups. In the COPD group, MDA levels 3 h after exercise were significantly higher than at baseline. In contrast there were no significant differences in MDA, VE and GSH levels in the control group after exercise. VE and MDA levels increased significantly after exercise in COPD patients but there was no difference in GSH levels. Baseline exercise time was significantly lower in the COPD group than in the controls. In 10 COPD patients who were given antioxidant therapy, their exercise time increased significantly and there was no increase in MDA and VE levels after the repeated exercise test. CONCLUSIONS: Antioxidant levels were significantly lower in COPD patients than in control subjects. In these patients, exercise results in more significant oxidative stress and lipid peroxidation than in control subjects and antioxidant therapy may decrease lipid peroxidation following exercise and improve exercise capacity.  相似文献   
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