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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   
2.

Background

Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.

Methods

A total of 1,331 consecutive patients at a single academic institution were reviewed from a prospectively collected database. Preoperative data collected included demographics, body mass index, and percent excess weight loss. Postoperative BMI and %EWL were collected at 12, 24, and 36 months. Percent excess weight loss was analyzed by the percentiles of excess weight lost, and the distribution of percent excess weight loss was evaluated in 10% increments. Lack of a successful treatment effect was defined as <25% excess weight loss.

Results

Of the 1,331 patients, 72.4% (963) underwent laparoscopic Roux-en-Y gastric bypass, 18.3% (243) laparoscopic sleeve gastrectomy, and 9.4%(125) laparoscopic adjustable gastric banding. Mean percent excess weight loss was greatest for laparoscopic Roux-en-Y gastric bypass, followed by laparoscopic sleeve gastrectomy, and then by laparoscopic adjustable gastric banding at every time point: at 2 years mean percent excess weight loss was 77.9± 24.4 for laparoscopic Roux-en-Y gastric bypass, 50.8 ± 25.8 for laparoscopic sleeve gastrectomy, and 40.8± 25.9 for laparoscopic adjustable gastric banding (P < .0001). The rates of a successful treatment effect s for laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding were 0.9%, 5.2%, and 24.3% at 1 year; 0.3%, 11.1%, and 26.0% at 2 years; and 1.0%, 25.3%, and 30.2% at 3 years. At 1 year, the odds ratio of lack of a successful treatment effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass was 6.305 (2.125–19.08; P?=?.0004), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass was 36.552 (15.64–95.71; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy was 5.791 (2.519–14.599; P < .0001). At 2 years, the odds ratio for laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass increased to 70.7 (9.4–531.7; P < .0001), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass increased to 128.1 (16.8–974.3; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy decreased to 1.8 (0.9–3.6; P?=?.09).

Conclusion

This study emphasizes the existing variability in weight loss across bariatric procedures as well as in the lack of a treatment effect for each procedure. Although laparoscopic adjustable gastric banding has the greatest rate of a lack of a successful treatment effect, the rate remained stable over 3 years postoperatively. Laparoscopic sleeve gastrectomy showed a doubling in the rate of a lack of a successful treatment effect every year reaching 25% at year 3. The rates for lack of a successful treatment effect for laparoscopic Roux-en-Y gastric bypass remained stable at about 1% for the first 3 years postoperatively.  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   
5.
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   
6.
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   
7.
Analysis of the p21 gene in gliomas   总被引:4,自引:0,他引:4  
The p21 gene encodes a cyclin dependent kinase inhibitor protein (p21) which has a tumor suppressive activity in a variety of tumor cell lines. Since, the p21 gene is up-regulated by the p53 tumor suppressor gene, which is frequently mutated in gliomas, acting therefore in the same control pathway, it constitutes a good candidate gene to be also inactivated in these tumors. To test this hypothesis, DNAs from 81 gliomas (48 glioblastomas, 11 anaplastic astrocytomas, 10 low-grade astrocytomas, 12 oligodendrogliomas and mixed gliomas), were investigated for mutations in the p21 coding sequence by denaturant gradient gel electrophoresis followed by sequencing. All these tumors have been previously screened for p53 mutations. Three different DNA variants were identified on codon 31 (17 cases), 27 (1 case) and 117 (1 case) and shown to be also present in matching constitutional DNA, suggesting they were polymorphisms. None of the tumors demonstrated a somatic mutation. No significant correlation between the presence of a p21 variant and the p53 mutation tumor status was observed. In conclusion, mutation in the p21 gene unlikely contributes to the development of gliomas.  相似文献   
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