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1.
PurposeManagement of head and neck cancers (HNC) in older adults is a common but challenging clinical scenario. We assess the impact of Stereotactic Body Radiation Therapy (SBRT) on survival utilizing the Geriatric-8 (G8) questionnaire.Materials and methods171 HNC patients, deemed medically unfit for definitive treatment, were treated with SBRT ± systemic therapy. G8 questionnaires were collected at baseline, at 4–6 weeks, and at 2–3 months post-treatment. Patients were stratified according to their baseline G8 score: <11 as ‘vulnerable’, 11–14 as ‘intermediate’, and >14 as ‘fit’. Overall survival (OS) was assessed through univariate Kaplan Meier analysis. Repeated measures ANOVA was used to determine if baseline characteristics affected G8 score changes.ResultsMedian follow-up was seventeen months. 60% of patients presented with recurrent HNC, 30% with untreated HNC primaries, and 10% with metastatic non-HNC primaries. Median age was 75 years. Median Charlson Comorbidity Index score was 2. 51% of patients were ‘vulnerable’, 37% were ‘intermediate’, and 12% were ‘fit' at baseline, with median survival of 13.2, 24.3, and 41.0 months, respectively (p = .004). Patients who saw a decrease in their follow-up G8 score (n = 69) had significantly lower survival than patients who had stable or increased follow-up G8 scores (n = 102), with median survival of 8.6 vs 36.0 months (p < .001).ConclusionThe G8 questionnaire may be a useful tool in upfront treatment decision-making to predict prognosis and prevent older patients from receiving inappropriate anti-cancer treatment. Decline in follow-up G8 scores may also predict worse survival and aid in goals of care following treatment.  相似文献   
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Unsaturated polyamides from methyl-fumaric (2-methyl-fumaric and 2.3-dimethyl-fumaric) acid dichlorides and diamines, i.e. 1.6-hexamethylenediamine, 1.10-decamethylenediamine, m-xylylenediamine, piperazine and trans-2.5-dimethylpiperazine were synthesized by low-temperature polycondensation. The polymer structures and properties were investigated by IR, X-ray, NMR, DSC, and TGA analyses. All polyamides were found to be soluble in several volatile organic solvents: furthermore – unlike polyamides derived from unsubstituted fumaric acid – polyamides from substituted fumaric acid derived from primary diamines showed melting or softening points.  相似文献   
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BACKGROUND: Endometriosis and possible rectal involvement are difficult to assess by physical examination. Previous studies have shown the diagnostic value of magnetic resonance imaging and rectal endoscopic sonography (RES) in this setting, but not that of transvaginal sonography (TVS). The aims of this study were to compare the accuracy of TVS and RES for the diagnosis of pelvic endometriosis, and to compare the results with histological findings. PATIENTS AND METHODS: In a prospective study, 30 consecutive patients referred with clinical signs of endometriosis underwent TVS and RES; the images were interpreted blindly with regard to physical findings. RESULTS: Endometriosis was confirmed histologically in 28 (93%) of the 30 patients. Endometriomas were also present in 67% of cases. For the diagnosis of uterosacral endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 75 and 75%, 83 and 67, 95 and 90%, and 45 and 40% respectively. For the diagnosis of rectosigmoid endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 95 and 82%, 100 and 88%, 100 and 95%, and 89 and 64% respectively. CONCLUSION: Despite the large proportion of our patients who had intestinal endometriosis, representing a possible source of bias, our results suggest that TVS is as efficient as RES for detecting posterior pelvic endometriosis and should therefore be used as the first-line examination.  相似文献   
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The ATP-binding cassette transporter A1 (ABCA1) modulates the transbilayer distribution of phosphatidylserine at the outer leaflet of the plasma membrane. This external exposure of phosphatidylserine is a hallmark of microparticle production and is impaired in ABCA1(-/-) mice. In this study, we report about the complete resistance to cerebral malaria of these mice. On analysis of histological and systemic parameters we evidenced an impairment of cellular responses to Plasmodium berghei ANKA infection in ABCA1(-/-) mice, as shown by lower plasma tumor necrosis factor levels, a weaker up-regulation of endothelial adhesion molecules in brain microvessels, a reduced leukocyte sequestration, as well as an ablated platelet accumulation. Besides, the number and the procoagulant activity of microparticles were dramatically reduced in the plasma of ABCA1(-/-) compared to ABCA1(+/+) mice. Moreover, microparticles derived from Plasmodium berghei ANKA-infected ABCA1(+/+) mice induced a significant increase of tumor necrosis factor release by noninfected macrophages. In ABCA1(-/-) mice platelet and macrophage responses to vesiculation agonists were ablated and reduced, respectively. Altogether, by pointing out the ABCA1 transporter as a major element controlling cerebral malaria susceptibility, these data provide a novel insight into its pathophysiological mechanisms and are consistent with a pathogenic role of microparticles in this neurological syndrome.  相似文献   
6.
Endometriosis is subsequent to the ability of endometrial glands to invade normal tissues. Matrix metalloproteinases (MMPs)—enzymes that mediate normal tissue turnover, including endometrial breakdown during menstruation—appear to be involved in this invasive process. Here, we examined the immunohistochemical expression of MMP-2, MMP-3, MMP-11, tissue inhibitor metalloproteinase (TIMP)-1 and TIMP-2 in endometrium from women with (n=9) or without endometriosis (n=18) in comparison with peritoneal (n=20), ovarian (n=20) and colorectal endometriosis (n=20). Women with endometriosis showed decreased endometrial MMP-2 expression compared with women without endometriosis (mean±SD positive cells: 24.3±28.3% and 69.3±12.1%), together with loss of MMP-3 expression (0 versus 17.5%±20.2). MMP-11, TIMP-1 and TIMP-2 expression was similar in the two groups. Endometrial MMP-2, -3 and -11 expression and TIMP-1 and -2 expression were similar in women with endometriosis and in those with peritoneal endometriosis. MMP-2, -3 and -11 expression was higher in colorectal endometriosis than in ovarian and peritoneal endometriosis. TIMP-2 expression was lower in colorectal endometriosis (P=0.0002) and ovarian endometriotic cysts (P=0.003) than in peritoneal endometriosis. TIMP-1 expression did not vary according to the location of endometriotic lesions. These results suggest that MMP-2 and -3 and TIMP-2 may be involved in the pathogenesis of endometriosis. Interestingly, MMP-2 and -3 overexpression was related to the infiltrative nature of endometriotic lesions, with possible sequential expression from peritoneal to colorectal endometriosis.  相似文献   
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The effect of high-dose uridine on body temperatures of rabbits and man has been studied in relation to plasma concentrations of uridine and its catabolite uracil. Uridine induced fever in both rabbits and man. High-dose cytidine had no influence on body temperature in rabbits. Plasma concentrations of uridine were between 1 and 1.5 mM at 30 min after an iv bolus injection of 400 mg uridine/kg in rabbits and reached peak levels of 2 mM after a 1-hr infusion of 12 g uridine/m2 in man. The plasma concentration of cytidine in rabbits was about 0.5 mM and that of uridine was 0.30 mM at 30 min after an iv bolus injection of 400 mg cytidine/kg. The mean residence time for uridine in patients and rabbits varied between 80 and 195 min. The area under the plasma concentration–time curve (AUC) for uridine in rabbits was 2.0 mmol · hr/liter, and that for cytidine was 0.6 mmol · hr/liter. A large AUC for uridine indicates a prolonged exposure of tissues to uridine, which might lead to extensive formation of degradation products. The administration of some of these catabolites, dihydrouracil (at 20–40 mg/kg), carbamyl--alanine (at 60 mg/kg), and -alanine (at 300–400 mg/kg), resulted in a significant increase in body temperature. It is concluded that the change in body temperature associated with uridine administration was not due to bacterial pyrogens but that one of the degradation products might be involved in thermoregulation.  相似文献   
8.
BackgroundTotal mesorectal excision is the gold standard treatment of mid- and low-lying rectal cancer. Lateral pelvic lymph node dissection has been suggested as an approach to decrease recurrence and improve survival. Our meta-analysis presented here aimed to review the current outcomes of lateral pelvic lymph node dissection and total mesorectal excision in comparison with total mesorectal excision alone.MethodsA systematic literature search querying electronic databases was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. We reviewed articles that reported the outcomes of lateral pelvic lymph node dissection combined with total mesorectal excision in comparison with total mesorectal excision alone. The main outcome measures were local recurrence, distant metastasis, overall and disease free-survival, and complications.ResultsThis systematic review included 29 studies of 10,646 patients. Of those patients, 39.4% underwent total mesorectal excision with lateral pelvic lymph node dissection. The median operation time for the lateral pelvic lymph node dissection + total mesorectal excision was significantly longer than total mesorectal excision alone (360 minutes versus 294.7 minutes, P = .02). Lateral pelvic lymph node dissection + total mesorectal excision was associated with higher odds of overall complications (odds ratio = 1.48, 95% confidence interval: 1.18–1.87, P < .001) and urinary dysfunction (odds ratio = 2.1, 95% confidence interval: 1.21–3.67, P = .008) than total mesorectal excision alone. Both groups had similar rates of male sexual dysfunction (odds ratio = 1.62, 95% confidence interval: 0.94–2.79, P = .08), anastomotic leakage (odds ratio = 1.15, 95% confidence interval: 0.69–1.93, P = .59), local recurrence (hazard ratio = 0.96, 95% confidence interval: 0.75–1.25, P = .79), distant metastasis (hazard ratio = 0.96, 95% confidence interval: 0.76–1.2, P = .72), overall survival (hazard ratio = 1.056, 95% confidence interval: 0.98–1.13, P = .13), and disease-free survival (hazard ratio = 1.02, 95% confidence interval: 0.97–1.07, P = .37).ConclusionLateral pelvic lymph node dissection was not associated with a significant reduction of recurrence rates or improvement in survival as compared with total mesorectal excision alone; however, LPLND was associated with longer operation time and increased complication rate.  相似文献   
9.
BACKGROUND: The functional consequences of vascular remodeling in rat aorta allografts were studied at different times after transplantation (Tx). METHODS: At days 1, 3, 7, 14, 28, and 56 after Tx, rat aorta allografts (Dark Agouti [DA]-to-Lewis) were mounted as isolated organs, and their contractile properties tested with phenylephrine, KCl, or endothelin-1. Controls were native DA-aortae and DA-syngeneic grafts. Changes in alpha smooth muscle actin and morphology were assessed by immunoblotting and histology. RESULTS: PostTx syngeneic grafts presented similar functional and morphological properties to native aortae. In allografts, no morphological changes was detected at day 7 after Tx, but phenylephrine-induced vasoconstriction was reduced by 60%. Signs of medial smooth muscle cell (SMC) loss and adventitial inflammation were observed at day 14 after Tx, without neointima formation. A complete loss of contractile property was observed at day 28 after Tx in association with a 75% decrease in alpha-SMC actin, severe adventitial inflammation, and reduced medial cellularity. At this time, neointima was restricted to both edges of allografts. At day 56 after Tx, allografts were also not functional and exhibited neointima on their entire length. All these changes were prevented by treating recipients with cyclosporine (7.5 mg/kg/day). CONCLUSION: These results indicate that, after Tx, the contractile property of rat aorta allografts is altered before manifest vascular remodeling. Because this can be prevented by cyclosporine, it most likely reflects an acute rejection of SMC. These results also show that vascular graft dysfunction can be used to monitor the development of rejection in the rat aorta allograft model.  相似文献   
10.
PURPOSE: To prospectively evaluate the effect of adding whole-body (18)F-2-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography (PET) to conventional screening for distant metastases in patients with locally advanced breast cancer (LABC). PATIENTS AND METHODS: All women with LABC referred for participation in the LABC Spinoza trial were considered eligible for this study. Patients were included if chest x-ray, bone scan, liver ultrasound, or computed tomography scan performed by the referring physician failed to reveal distant metastases. They underwent whole-body FDG PET scanning before therapy. Patients with subsequently proven distant metastases were switched to alternative forms of chemotherapy, hormonal therapy, or both. RESULTS: Among the 48 patients evaluated with PET, 14 had abnormal FDG uptake, and metastases were suspected in 12. After simple clinical evaluation (plain x-ray, history), 10 sites that were suggestive of abnormality remained. Further work-up revealed that four sites were metastases. Proven false positivity occurred in one patient with sarcoidosis. In the other five patients, the reason for abnormal FDG uptake (liver, lung, bone) remained unclear, and patients were treated as planned. Eleven months later, distant metastases were found in one patient at sites unrelated to the previous FDG uptake. CONCLUSION: The addition of FDG PET to the standard work-up of patients with LABC may lead to the detection of unexpected distant metastases. This may contribute to a more realistic stratification between patients with true stage III breast cancer and those who are in fact suffering from stage IV disease. Abnormal PET findings should be confirmed to prevent patients from being denied appropriate treatment.  相似文献   
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