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Our aim was to investigate the prognosis of patients with squamous cell carcinoma (SCC) of the gingiva who had preoperative dental operations. We studied 102 patients who were being operated on for SCC of the gingiva with special reference to the effects of preoperative dental operations on the prognosis. Twenty-six patients had dental procedures such as tooth extraction, or incision, or curettage before they visited our hospital, while the remaining 76 had no such interventions. The percentage of patients with advanced T stage disease (T3 or T4) was higher among those who had interventions (17/26, 65%) than among those who had not (35/76, 46%). The difference was not significant. Histopathologically invaded nodes were detected in half the patients in the intervention group (13/26), while they were found in only 18/76 (24%) of those in the no intervention group (p < 0.02). The incidence of nodal metastases with extranodal spread was significantly higher in the intervention group than in the no intervention group (p < 0.05), and those in the intervention group were more likely to develop distant metastases than those in the other group (p < 0.001). The 5-year survival in the two groups was 65% and 92%, respectively (p < 0.01). Preoperative dental operations such as tooth extraction, incision, or curettage possibly lead to regional and distant metastases and therefore a poor prognosis in patients with SCC of the gingiva.  相似文献   
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IntroductionIn this study, we investigated whether such a discontinuation of oral bisphosphonate (BP) for 3 months might influence the incidence of BP-related osteonecrosis of the jaw (BRONJ) and wound healing after tooth extraction in patients receiving oral BP therapy.Material and methodsThere were a total of 434 teeth in 201 patients (18 males and 183 females). The patients were divided into two groups depending on whether or not they underwent a 3-month discontinuation of BP therapy (BP? and BP+) before tooth extraction. In this observational study investigated delayed wound healing after tooth extraction in patients receiving oral BP therapy.ResultsIn all cases of the BP? group, there were no BRONJ although there was delayed wound healing in two cases. However, in one case of the BP+ group, oral BP was continued because it was deemed high risk to discontinue treatment by the patient's physician. In this case, an intraoral fistula was still present with bone exposure at 120 weeks after extraction (BRONJ stage 1).ConclusionThis study supports the idea of a drug holiday and encourages further clinical research on this topic of tooth extraction in patients receiving oral BP therapy.  相似文献   
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The MERA monopivot centrifugal pump has been developed for use in open‐heart surgery, circulatory support, and bridge‐to‐decision for up to 4 weeks. The pump has a closed‐type, 50‐mm diameter impeller with four straight paths. The impeller is supported by a monopivot bearing and is driven by a radial‐flux magnet‐coupling motor. Because flow visualization experiments have clarified sufficient pivot wash and stagnation at the sharp corner of the pivot support was suggested, sharp corners were removed in the design stage. The index of hemolysis of the pump operating at more than 200 mm Hg was found to be lower than that of a commercial pump. Four‐week animal tests were then conducted two times; improvement of thrombus formation was seen in the female pivot through modification of female pivot geometry. Overall antithrombogenicity was also recorded. Finally, to assure mid‐term use, an additional 4‐week durability test revealed that the rate of the axial pivot wear was as small as 1.1 µm/day. The present in vitro and in vivo studies revealed that the MERA monopivot centrifugal pump has sufficient hemocompatibility and durability for up to 4 weeks.  相似文献   
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This was a case–control study to analyze the associations between calcium urolithiasis and the urokinase polymorphisms, P141L (rs2227564) and 3′-UTR C>T (rs4065), in a Japanese population. Cases consisted of 232 patients with urinary calcium stones (174 men and 58 women) who presented to a general hospital between April 2009 and June 2011. Among these cases, 115 (49.6 %) patients had calcium oxalate stones alone, and 113 (48.7 %) patients had calcium oxalate stones mixed with calcium phosphate stones. Controls consisted of 454 subjects who had a routine health check-up in the same prefecture. The two polymorphisms were genotyped via polymerase chain reaction with confronting two-pair primers. In the control group, the genotype frequencies of P141L were 0.573 for PP, 0.375 for PL, and 0.052 for LL, and those of 3′-UTR C>T were 0.835 for CC, 0.165 for CT, and TT was not identified. Neither of the polymorphisms was significantly associated with urolithiasis. The age- and sex-adjusted odds ratios of urolithiasis were 0.96 [95 % confidence interval (CI), 0.66–1.41] for PL and 1.22 (0.58–2.57) for LL as compared with PP genotype of P141L, and 1.01 (0.62–1.64) for CT as compared with CC genotype of 3′-UTR C>T. When compared with the PP genotype of P141L, the frequency of PL was significantly lower in female cases with a family history of urolithiasis than in females without such family history (p = 0.028). P141L and 3′-UTR polymorphisms of the urokinase gene are not associated with urolithiasis in a Japanese population.  相似文献   
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Background

The mitochondrial protein frataxin regulates iron metabolism for heme and iron sulfur cluster synthesis in the mitochondria and could be associated with the regulation of oxidative stress. To clarify the expression of frataxin and its association with uremia, we evaluated the mRNA and protein levels of frataxin in the polymorphonuclear leukocytes (PMNLs) of patients on hemodialysis (HD).

Methods

Uremic patients on HD (n = 18) and healthy control subjects (n = 18) were investigated. PMNLs were isolated by differential centrifugation. The mRNA levels of frataxin in isolated leukocytes were quantified by TaqMan real-time polymerase chain reaction. Frataxin protein expression in the cell lysate was evaluated using SDS-polyacrylamide gel electrophoresis and Western blotting.

Results

The frataxin/glyceraldehyde-3-phosphate dehydrogenase mRNA ratio in PMNLs from uremic patients was significantly lower than that in control subjects. Frataxin protein expression in uremic patients was also significantly lower than that in controls. Multiple regression analysis showed that frataxin mRNA levels were independently associated with the serum levels of both the oxidative stress marker malondialdehyde and the proinflammatory cytokine tumor necrosis factor-α.

Conclusion

The downregulation of frataxin seems to be linked with uremic status, which is usually associated with chronic inflammation and the acceleration of oxidative stress. Mitochondrial iron regulation may play a role in several comorbidities and in the poor prognosis in uremic patients. Further investigation is needed to elucidate whether reduced frataxin levels are linked to the pathological status of uremic patients and whether uremic substances affect frataxin expression.  相似文献   
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