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51.
PURPOSE Early-stage colon cancer patients (Dukes A or B; pT1–T3 pNO pMO) are excluded from adjuvant chemotherapy following potentially curative surgery because they are expected to have good long-term survival. However, 20 percent to 30 percent of these patients ultimately succumb from recurrent disease. This indicates that the conventional staging procedures may be unable to precisely predict cancer prognosis.METHODS In 65 early-stage colon cancers, we investigated by immunohistochemistry the role of molecular markers such as p27, p53, and vascular endothelial growth factor in identifying high-risk patients who may benefit from adjuvant treatments.RESULTS No clinicopathologic factor, namely Dukes stage, t parameter, number of resected nodes, and vascular or lymphatic invasion, was found be an independent significant predictor of disease-specific and disease-free survival. In contrast, each molecular marker predicted survival and recurrence rates much better than the conventional Dukes staging system. The best combination of variables for prediction of long-term outcome and recurrence rate included p27, p53, and vascular endothelial growth factor. Interestingly, the greater the number of molecular alterations, the lower the five-year estimated survival function. Nearly all cancer-related deaths were observed among patients whose colon cancers expressed all three molecular alterations. Regardless of Dukes stage, the recurrence rate was found to increase with the increase in the number of molecular alterations. Early-stage colon cancers expressing p27 down-regulation and high p53 and vascular endothelial growth factor immunoreactivity showed a 100 percent actuarial four-year recurrence rate.CONCLUSIONS Assessment of molecular alterations may be useful to identify a higher-risk group of early-stage colon cancer patients who may benefit from adjuvant chemotherapy.  相似文献   
52.
Obesity in children appears to be associated with increased risk of cardiovascular and metabolic diseases later in life. Early development of insulin resistance and impaired oxidant-antioxidant status may lead to endothelial dysfunction and increased carotid intima media thickness (IMT) even in childhood. The aim of this study was to measure IMT and the relationship between IMT, insulin resistance and oxidant status in obese pre-pubertal children. In 53 obese pre-pubertal children (27M/26F, mean age 8+/-2 years), anthropometric measurements and inflammatory markers (hs-CRP and PGF-2 alpha), were evaluated compared with 41 healthy pre-pubertal subjects (21M/20F, mean age 7+/-2 years). OGTT was performed and insulin resistance (IR) indices (HOMA-IR, WBISI, G/I and QUICKI) were calculated in all patients. High-resolution ultrasound techniques were used to evaluate IMT. Obese children had higher levels of PGF-2 alpha and hs-CRP compared to healthy subjects (p=0.001 and p=0.005). Furthermore, fasting insulin levels and HOMA-IR were higher in obese children than in controls (p=0.001 and p=0.001) while WBISI was significantly lower (p=0.002). In addition, obeses had an increased IMT (p=0.001). In obese children there was a significant correlation between IMT and indices of IR (HOMA-IR: beta=-1.233, p=0.002; WBISI: beta=-0.921, p=0.008; G/I: beta=-0.811, p=0.003) and between IMT and PGF-2 alpha (beta=0.505, p=0.004). After categorizing subjects according to tertiles of body mass index (BMI) (or=26.23 kg/m(2)) and to waist circumference (WC) (or=79.04 cm), no influence of BMI or WC on IMT were found in the three groups. In conclusion, early changes in glucose metabolism and an alteration of oxidant-antioxidant status may be present in obese pre-pubertal children; this could lead to increase IMT and early cardiovascular disease.  相似文献   
53.
OBJECTIVES: We set out to determine the effect of sustained treatment with nitroglycerin (GTN) on neural modulation of heart rate in humans. BACKGROUND: Acutely, exogenous and endogenous nitric oxide reduces sympathetic, while increasing vagal, outflow. An animal study showed loss of these effects during nitrate tolerance. METHODS: A total of 29 healthy men (age range, 18 to 32 years) received transdermal GTN (0.6 mg/h/24 h) or no therapy for six days in a parallel controlled trial. The reflex regulation of heart rate was assessed with the spontaneous baroreflex sensitivity (BRS) method. Heart rate variability was calculated both in time (standard deviation of mean RR interval [RRSD]) and frequency domains (Fast Fourier Transformation) over 10-min intervals. RESULTS: Systolic blood pressure was unchanged after continuous GTN, whereas mean RR interval decreased significantly (from 839 to 781 ms, p < 0.05). Nitroglycerin blunted BRS (p < 0.05). When compared with untreated subjects, RRSD was significantly lower after GTN, whereas the ratio of low to high frequencies was increased (all p < 0.05). CONCLUSIONS: Chronic GTN reduces tonic and reflex vagal heart rate modulation, resulting in greater relative sympathetic influence. Importantly, such changes in the regulation of chronotropic oscillations might have negative prognostic implications in both heart failure and coronary artery disease. Furthermore, because chronic GTN alters the blood pressure/heart rate relationship, our data suggest caution when using these variables as pharmacodynamic markers for the development of nitrate tolerance.  相似文献   
54.
We aimed to evaluate the role of two-dimensional speckle tracking imaging (2DSTI) in detecting early changes of myocardial deformation in patients affected by thalassemia major (TM) and its relation with myocardial iron overload (MIO) detected by T2* cardiovascular magnetic resonance (CMR). We studied 28 TM patients (15 males, 37.4?±?10 years). All patients underwent CMR and echocardiography in the same day. Segmental and global T2* values were measured. Values of global longitudinal strain (GLS) were derived from the three apical views, while radial and circumferential strain were obtained as average strain from the short axis views at basal, mid and apical level. Six patients (21.4%) showed significant MIO (global heart T2*?<?20 ms). GLS showed a significant correlation with T2* values (R?=??0.49; P?=?0.001) and it was significantly lower in patients with a significant MIO than in those with no significant MIO (?18.3?±?2 vs. ?21.3?±?2.7, P?=?0.02). No significant difference was found for radial and circumferential strain in relation to the severity of MIO. Patients with impaired GLS (<?19.5%) had a significant higher risk of showing significant MIO (Odds-ratio-OR?=?17; 95%). GLS is related with global T2* in TM patients. Moreover, GLS can identify TM patients with severe MIO detected by CMR.  相似文献   
55.
56.

Objective

To compare the risk of falls and fall predictors in patients with Parkinson disease (PD), multiple sclerosis (MS), and stroke using the same study design.

Design

Multicenter prospective cohort study.

Setting

Institutions for physical therapy and rehabilitation.

Participants

Patients (N=299) with PD (n=94), MS (n=111), and stroke (n=94) seen for rehabilitation.

Interventions

Not applicable.

Main Outcome Measures

Functional scales were applied to investigate balance, disability, daily performance, self-confidence with balance, and social integration. Patients were followed for 6 months. Telephone interviews were organized at 2, 4, and 6 months to record falls and fall-related injuries. Incidence ratios, Kaplan-Meier survival curves, and Cox proportional hazards models were used.

Results

Of the 299 patients enrolled, 259 had complete follow-up. One hundred and twenty-two patients (47.1%) fell at least once; 82 (31.7%) were recurrent fallers and 44 (17.0%) suffered injuries; and 16%, 32%, and 40% fell at 2, 4, and 6 months. Risk of falls was associated with disease type (PD, MS, and stroke in decreasing order) and confidence with balance (Activities-specific Balance Confidence [ABC] scale). Recurrent fallers were 7%, 15%, and 24% at 2, 4, and 6 months. The risk of recurrent falls was associated with disease type, high educational level, and ABC score. Injured fallers were 3%, 8%, and 12% at 2, 4, and 6 months. The only predictor of falls with injuries was disease type (PD).

Conclusions

PD, MS, and stroke carry a high risk of falls. Other predictors include perceived balance confidence and high educational level.  相似文献   
57.
58.

Purpose

The soluble receptor for advanced glycation end-products (sRAGE) is a marker of lung epithelial injury and alveolar fluid clearance (AFC), with promising values for assessing prognosis and lung injury severity in acute respiratory distress syndrome (ARDS). Because AFC is impaired in most patients with ARDS and is associated with higher mortality, we hypothesized that baseline plasma sRAGE would predict mortality, independently of two key mediators of ventilator-induced lung injury.

Methods

We conducted a meta-analysis of individual data from 746 patients enrolled in eight prospective randomized and observational studies in which plasma sRAGE was measured in ARDS articles published through March 2016. The primary outcome was 90-day mortality. Using multivariate and mediation analyses, we tested the association between baseline plasma sRAGE and mortality, independently of driving pressure and tidal volume.

Results

Higher baseline plasma sRAGE [odds ratio (OR) for each one-log increment, 1.18; 95% confidence interval (CI) 1.01–1.38; P?=?0.04], driving pressure (OR for each one-point increment, 1.04; 95% CI 1.02–1.07; P?=?0.002), and tidal volume (OR for each one-log increment, 1.98; 95% CI 1.07–3.64; P?=?0.03) were independently associated with higher 90-day mortality in multivariate analysis. Baseline plasma sRAGE mediated a small fraction of the effect of higher ΔP on mortality but not that of higher VT.

Conclusions

Higher baseline plasma sRAGE was associated with higher 90-day mortality in patients with ARDS, independently of driving pressure and tidal volume, thus reinforcing the likely contribution of alveolar epithelial injury as an important prognostic factor in ARDS. Registration: PROSPERO (ID: CRD42018100241).
  相似文献   
59.
Chronic rejection (CR) of liver allografts causes damage to intrahepatic vessels and bile ducts and may lead to graft failure after liver transplantation. Although its prevalence has declined steadily with the introduction of potent immunosuppressive therapy, CR still represents an important cause of graft injury, which might be irreversible, leading to graft loss requiring re-transplantation. To date, we still do not fully appreciate the mechanisms underlying this process. In addition to T cell-mediated CR, which was initially the only recognized type of CR, recently a new form of liver allograft CR, antibody-mediated CR, has been identified. This has indeed opened an era of thriving research and renewed interest in the field. Liver biopsy is needed for a definitive diagnosis of CR, but current research is aiming to identify new non-invasive tools for predicting patients at risk for CR after liver transplantation. Moreover, the minimization or withdrawal of immunosuppressive therapy might influence the establishment of subclinical CR-related injury, which should not be disregarded. Therapies for CR may only be effective in the “early” phases, and a tailored management of the immunosuppression regimen is essential for preventing irreversible liver damage. Herein, we provide an overview of the current knowledge and research on CR, focusing on early detection, identification of non-invasive biomarkers, immunosuppressive management, re-transplantation and future perspectives of CR.  相似文献   
60.
Summary The anti-inflammatory agent diftalone was administered in the diet to male and female BALB/c mice at 300-, 600-, and 1200-ppm dose levels for 80 weeks, starting at 8 weeks of age. The animals were kept under observation until 126–128 weeks of age, when the experiment was terminated. Diftalone treatment at the highest dose was hepatotoxic and induced hepatocellular tumors in females, angiomas of the liver in males, and angiosarcomas of the liver in male and female mice. The 300- and 600-ppm dose levels were not carcinogenic. The compound was not mutagenic for Salmonella typhimurium.  相似文献   
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