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61.
Air pollution consists of a heterogeneous mixture of gasses and particles that include carbon monoxide, nitrates, sulfur dioxide, ozone, lead, toxic by-product of tobacco smoke and particulate matter. Oxidative stress and inflammation induced by inhaled pollutants may result in acute and chronic disorders in the respiratory system, as well as contribute to a state of systemic inflammation and autoimmunity. This paper reviews the mechanisms of air contaminants influencing the immune response and autoimmunity, and it focuses on studies of inhaled pollutants triggering and/or exacerbating rheumatic diseases in cities around the world. Remarkably, environmental factors contribute to the onset of autoimmune diseases, especially smoking and occupational exposure to silica in rheumatoid arthritis and systemic lupus erythematosus. Other diseases such as scleroderma may be triggered by the inhalation of chemical solvents, herbicides and silica. Likewise, primary vasculitis associated with anti-neutrophil cytoplasmic antibody (ANCA) may be triggered by silica exposure. Only few studies showed that air pollutants could trigger or exacerbate juvenile idiopathic arthritis and systemic lupus erythematosus. In contrast, no studies of tropospheric pollution triggering inflammatory myopathies and spondyloarthropathies were carried out. In conclusion, air pollution is one of the environmental factors involved in systemic inflammation and autoimmunity. Further studies are needed in order to evaluate air pollutants and their potentially serious effects on autoimmune rheumatic diseases and the mechanisms involved in the onset and the exacerbation of these diseases.  相似文献   
62.
BackgroundIntrahepatic lithiasis (IHL) is a rare disease in the western world. Complications associated with IHL include acute cholangitis, liver atrophy, secondary biliary cirrhosis, and risk for intrahepatic cholangiocarcinoma. Liver resection is considered the treatment of choice for IHL. The objective of this study was to analyze patients who underwent liver resection for non-Asian hepatolithiasis.Methods127 patients with symptomatic non-Asian hepatolithiasis underwent resection in six institutions. Demographic data, clinical presentation, diagnosis, classification according to stone location, presence of atrophy, bile duct stricture, biliary cirrhosis, incidence of cholangiocarcinoma, treatment and postoperative course were evaluated.Results52 patients (40.9%) were male and the mean age was 46.1 years. Sixty-six patients (51.9%) presented with history of cholangitis. Stones were located in the left lobe in 63 (49.6%), and right lobe in 28 patients (22.0%). Atrophy was observed in 31 patients (24.4%) and biliary stenosis in 18 patients (14.1%). The most common procedure performed was left lateral sectionectomy in 63 (49.6%) patients, followed by left hepatectomy in 36 (28.3%), right hepatectomy in 19 (15.0%), and associated hepaticojejunostomy in 28 (22.0%). Forty-two patients (33.0%) presented postoperative complications and the most common were biliary fistula (13.3%) and surgical site infection (7.0%). Postoperative mortality was 0.7%. Intrahepatic cholangiocarcinoma was observed in 2 patients (1.5%). Recurrence was identified in 10 patients (7.8%), mostly with bilateral stones and/or hepaticojejunostomy.ConclusionLiver resection is the standard treatment for symptomatic unilateral or complicated IHL with good operative results. Risk of cholangiocarcinoma was low in non-Asian patients.  相似文献   
63.

Purpose

The aim of our work was to assess the role of dual-source computed tomography (DSCT) in the preoperative evaluation of coronary artery disease in patients scheduled for noncoronary cardiac surgery.

Materials and methods

One hundred patients were prospectively evaluated. Patients negative for coronary disease at DSCT (n=81) underwent surgery without coronary angiography. Patients positive for significant lesions or with nondiagnostic image quality due to artefacts or severe calcifications underwent coronary angiography (n=19) and were excluded from the study. In patients who underwent surgery with only a DSCT diagnosis, we evaluated the frequency of major adverse cardiac events (MACEs) during the perioperative period and at 3 months follow-up.

Results

No MACEs were recorded during the perioperative period; three noncardiac complications (one surgical revision for bleeding, one cardiac tamponade and one respiratory insufficiency) and one death related to severe respiratory insufficiency were observed. None of the 80 patients had MACEs during the 3-month follow-up period.

Conclusions

Coronary evaluation with DSCT is able to rule out the presence of coronary disease in patients scheduled for cardiac surgery, without the need for coronary angiography confirmation. Patients with significant stenosis or nondiagnostic image quality should be referred for coronary angiography.  相似文献   
64.
Breast cancer affects patients both emotionally and physically. It is time to consider distress as the sixth vital sign in breast cancer patients in Europe. Between 2012 and 2015, our EUSOMA‐certified multi‐disciplinary group conducted a study on emotional distress and quality‐of‐life in breast cancer patients at diagnosis, and observed their trend over the first 8 months of treatment. One hundred and forty‐nine patients concluded the program. The psycho‐oncologist and the breast nurses gave out SF36, Hospital Anxiety and Depression Scale and Distress Thermometer. Our Italian data go along with the reported literature on distress and quality‐of‐life. Despite modern advances, experiencing breast cancer impacts on overall quality‐of‐life.  相似文献   
65.

Background

The impact of primary tumor location on overall survival (OS), recurrence-free survival (RFS), and long-term outcomes has not been well established in patients undergoing potentially curative resection of colorectal liver metastases (CRLM).

Methods

A single-institution database was queried for initial resections for CRLM 1992–2004. Primary tumor location determined by chart review (right = cecum to transverse; left = splenic flexure to sigmoid). Rectal cancer (distal 16 cm), multiple primaries, and unknown location were excluded. Kaplan–Meier and Cox regression methods were used. Cure was defined as actual 10-year survival with either no recurrence or resected recurrence with at least 3 years of disease-free follow-up.

Results

A total of 907 patients were included with a median follow-up of 11 years; 578 patients (64%) had left-sided and 329 (36%) right-sided primaries. Median OS for patients with a left-sided primary was 5.2 years (95% confidence interval [CI] 4.6–6.0) versus 3.6 years (95% CI 3.2–4.2) for right-sided (p = 0.004). On multivariable analysis, the hazard ratio for right-sided tumors was 1.22 (95% CI 1.02–1.45, p = 0.028) after adjusting for common clinicopathologic factors. Median RFS was marginally different stratified by primary location (1.3 vs. 1.7 years; p = 0.065). On multivariable analysis, location of primary was not significantly associated with RFS (p = 0.105). Observed cure rates were 22% for left-sided and 20% for right-sided tumors.

Conclusions

Among patients undergoing resection of CRLM, left-sided primary tumors were associated with improved median OS. However, long-term survival and recurrence-free survival were not significantly different stratified by primary location. Patients with left-sided primary tumors displayed a prolonged clinical course suggestive of more indolent biology.
  相似文献   
66.

Background

Hepatic resection of colorectal liver metastases is associated with long-term survival. This study analyzes actual 10-year survivors after resection of colorectal liver metastases, reports the observed rate of cure, and identifies factors that preclude cure.

Methods

A single-institution, prospectively maintained database was queried for all initial resections for colorectal liver metastases for the years 1992–2004. Observed cure was defined as actual 10-year survival with either no recurrence or resected recurrence with at least 3 years of disease-free follow-up. Clinical risk score was dichotomized into low (0–2) and high (3–5). Semiparametric proportional hazards mixture cure model was utilized to estimate probability of cure.

Results

We included 1,211 patients with a median follow-up for survivors of 11 years. Median disease-specific survival was 4.9 years (95% CI: 4.4–5.3). 295 patients (24.4%) were actual 10-year survivors. The observed cure rate was 20.6% (n?=?250). Among 250 cured patients, 192 (76.8%) had no recurrence and 58 (23.2%) had a resected recurrence with at least 3 years of disease-free follow-up. Extrahepatic disease (n?=?88), carcinoembryonic antigen >200?ng/mL (n?=?119), positive margin (n?=?109), and >10 tumors (n?=?31) had observed cure rates less than 10%. In cure model analysis, patients with both extrahepatic disease and high clinical risk score (n?=?31) had an estimated probability of cure of 3.5%.

Conclusion

Actual 10-year survival after resection of colorectal liver metastases is 24% with an observed 20% cure rate. Patients with both high clinical risk score and extrahepatic disease have an estimated probability of cure less than 5%. When such factors are identified, strong consideration may be given to preoperative strategies, such as neoadjuvant chemotherapy, to help select patients for surgical therapy.  相似文献   
67.
The genotype–phenotype correlations of the specific BRCA1 and BRCA2 mutations in multi‐ethnic populations in USA have not yet been fully investigated. This study was designed to evaluate the effects of ethnicity at specific mutation locations and breast/ovarian cancer phenotypes. Our cohort included 445 women with different ethnic backgrounds who underwent BRCA genetic testing between 1997 and 2010. Known clinical and pathologic characteristics were compared with Chi‐Square Analysis or Fisher's Exact test as appropriate. The three most common mutation locations in BRCA1 (exons 2, 11, and 20) and BRCA2 (exons 10, 11, and 25) genes were chosen. Prevalence of BRCA1 exon 2 mutations were significantly higher in Ashkenazi Jewish (AJ) women compared to Caucasians (41% versus 15%; p = 0.001). Similarly, AJ women with breast cancer were more likely to have BRCA1 exon 2 mutation (47% positivity in AJ women versus 0–12.5% positivity in other ethnicities; p = 0.004). Women carrying the exon 20 BRCA1 mutation had the highest probability of having combined breast and ovarian cancers compared to women carrying other exon mutations (p = 0.05). The median age at initial cancer diagnosis, phenotypic features of breast cancer tumors, and overall survival did not vary significantly by ethnicity or mutation location. Our data suggest that ethnicity does not affect age of onset, overall survival or confer different risks of breast and ovarian cancer development in BRCA carriers. These results also suggest that women carrying the exon 20 BRCA1 mutation may warrant mutation‐specific counseling and be more aggressively managed for risk reduction.  相似文献   
68.

Purpose

To identify and compare predictors of local tumor progression (LTP)-free survival (LTPFS) after radiofrequency (RF) ablation and microwave (MW) ablation of colorectal liver metastases (CLMs).

Materials and Methods

This is a retrospective review of CLMs ablated from November 2009 to April 2015 (110 patients). Margins were measured on contrast-enhanced computed tomography (CT) 6 weeks after ablation. Clinical and technical predictors of LTPFS were assessed using a competing risk model adjusted for clustering.

Results

Technique effectiveness (complete ablation) was 93% (79/85) for RF ablation and 97% (58/60) for MW ablation (P = .47). The median follow-up period was significantly longer for RF ablation than for MW ablation (56 months vs. 29 months) (P < .001). There was no difference in the local tumor progression (LTP) rates between RF ablation and MW ablation (P = 0.84). Significant predictors of shorter LTPFS for RF ablation on univariate analysis were ablation margins 5 mm or smaller (P < .001) (hazard ratio [HR]: 14.6; 95% confidence interval [CI]: 5.2–40.9) and perivascular tumors (P = .021) (HR: 2.2; 95% CI: 1.1–4.3); both retained significance on multivariate analysis. Significant predictors of shorter LTPFS on univariate analysis for MW ablation were ablation margins 5 mm or smaller (P < .001) (subhazard ratio: 11.6; 95% CI: 3.1–42.7) and no history of prior liver resection (P < .013) (HR: 3.2; 95%: 1.3–7.8); both retained significance on multivariate analysis. There was no LTP for tumors ablated with margins over 10 mm (median LTPFS: not reached). Perivascular tumors were not predictive for MW ablation (P = .43).

Conclusions

Regardless of the thermal ablation modality used, margins larger than 5 mm are critical for local tumor control, with no LTP noted for margins over 10 mm. Unlike RF ablation, the efficiency of MW ablation was not affected for perivascular tumors.  相似文献   
69.
70.
Purpose: To clarify the experimental conditions that might influence the release of cytokines in the culture medium and give some basic input for building a model for cytokine (e.g., Interleukin-6, IL-6) regulation in the case of ‘sham irradiation’ and after ionising radiation exposure.

Materials and methods: The influence of cell type, cell density, medium volume, medium storage temperature and other methodological aspects on IL-6 and Interleukin-8 (IL-8) release were investigated. In addition, the effects over the time of different doses of gamma irradiation on the clonogenic survival of bystander cells and on the secretion of these cytokines were studied.

Results: We observed significant decreases of clonogenic survival in AG01522 and T98G cells after the transfer of medium collected 5 and 20 h after low doses of gamma irradiation. Concerning the Interleukins' measurements, our experiments showed that the aggregate removal modalities tested, and up to 10 freeze-thaw cycles, do not have significant influence on the measurements of IL-6 concentration in the medium. We also observed that the IL-6 accumulated in the medium of human fibroblasts is not degraded when maintained at 37°C. Sets of experiments demonstrated that cell density or medium volume do not influence the release of IL-6. On the contrary, our results showed that IL-8 released by glioblastoma cells strongly depends on the amount of medium. Finally, the exposure of fibroblasts to gamma irradiation has influence on the release kinetics of both IL-6 and IL-8 with peculiar features.

Conclusions: This study solved some of the methodological doubts concerning the study of bystander effects by means of the medium transfer technique; moreover it also highlighted some experimental aspects that need to be considered when approaching this sort of experiments.  相似文献   
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