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41.

Background

Emissions from vehicles are composed of heterogeneous mixtures of hazardous substances; several pollutants such as Polycyclic Aromatic Hydrocarbons (PAHs) are amongst the most dangerous substances detected in urban monitoring. A cohort of traffic policemen usually occupationally exposed to PAHs present in the urban environment were examined in order to assess the mutagenicity and DNA capacity repair.

Methods

Seventy-two urban traffic policemen working in Catania’s metropolitan area were enrolled in the study. Two spot urine samples were collected from each subject during the whole working cycle as follows: sample 1 (S1), pre-shift on day 1; sample 2 (S2) post-shift on day 6. 1-hydroxypyrene (1-OHP) was measured to serve as an indirect exposure indicator. Urinary mutagenic activity was assessed through the plate incorporation pre-incubation technique with S9, using YG1024 Salmonella typhimurium strain over-sensitive to PAH metabolite. Concentrations of urinary 8-oxodG were measured using liquid chromatography tandem mass spectrometry.

Results

As regards the exposure to PAHs, results highlighted a statistically significant difference (p?<?0.001) between pre-shift on day 1 and post-shift on day 6 levels. Mutagenic activity was detected in 38 (66%) workers on S1 and in 47 (81%) on S2. Also 8-oxodG analysis showed a statistically significant difference between S1 and S2 sampling.

Conclusions

This study demonstrated that occupational exposure to pollutants from traffic emission, assessed via 1-OHP measurements in urine, may lead to DNA repair and mutagenic activity, in line with other studies.
  相似文献   
42.
Objective The aim of the study was to identify factors associated with non-initiation and cessation of predominant breastfeeding (PBF) in a mother–child cohort from Spain. Materials and Methods The analysis included 2195 mother-infant from birth to 14 months post- delivery recruited between 2004 and 2008. Maternal characteristics were collected during the pregnancy. Lactation data were obtained at 6 and 14 months after delivery. PBF was defined as intake of breast milk plus liquids like juices or water. The PBF cessation was calculated using the date that women started PBF and the date that she reported to start giving infant formula and/or food. The relationship between maternal variables and PBF initiation and cessation was modeled using logistic and Cox proportional hazards regression analysis. Results The prevalence of PBF at hospital discharge was 85.3, 53.4% at 3 months, 46.1% at 4 months and 7.2% at 6 month. Only two women continued PBF at 12 months and none at 14 months. The initiating of PBF was associated with higher levels of maternal education, being a first-time mother and worked in a non-manual occupation. Higher level of physical activity, not smoking and having a healthy BMI, were also positively associated with PBF initiation. PBF cessation was higher in young, obese women, who had had complications during the pregnancy, and who had lower levels of education and smoked. The employment status of women, in week 32 of pregnancy and also in month 14 post-delivery, determined likelihood of PBF cessation. Conclusions Healthier habits and education positively influenced PBF initiation and duration. Decrease in PBF duration rates in Spain can be interpreted in part as a consequence of women returning to work.  相似文献   
43.
To determine the effects of echo-contrast agents (ECAs) on ultrasound (US)-induced apoptosis and cell lysis, human myelomonocytic lymphoma U937 cells in suspension were exposed to 1 MHz continuous waves US for 1 min at an intensity of 0.5, 1.0, 2.0 or 4.0 W/cm(2) with or without non-shell type ECA, Levovist (2 mg/ml), and shell type, Optison (1 microl/ml) or YM454 (1 microl/ml). Levovist minimally enhanced the US-induced apoptosis at 1.0 W/cm(2) while Optison and YM454 did at 2.0 and 4.0 W/cm(2), as detected by flow cytometry. Cell lysis was also augmented when Levovist was combined with US at 2.0 W/cm(2), and when Optison was combined with US at 2.0 and 4.0 W/cm(2). YM454 showed the highest rate of enhanced cell lysis at 1.0, 2.0 and 4.0 W/cm(2). Therefore, this study shows that Optison and YM454 are effective in augmenting the US-induced cell killing, but not Levovist. Another result indicates that cavitation plays a role in the augmented effects and that inertial cavitation appears necessary for Optison and YM454 to effect their actions. In addition, results show that the rate of apoptosis is lower in the presence of ECAs with higher free radical scavenging activity, suggesting a possible role for free radicals in apoptosis. These findings suggest that some ECAs have potential to be adjuncts in cases wherein augmented US-induced cell killing is needed, such as in cancer therapy with US.  相似文献   
44.
The current pandemic SARS-CoV-2 has required an unusual allocation of resources that can negatively impact chronically ill patients and high-complexity procedures. Across the European Reference Network on Pediatric Transplantation (ERN TransplantChild), we conducted a survey to investigate the impact of the COVID-19 outbreak on pediatric transplant activity and healthcare practices in both solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). The replies of 30 professionals from 18 centers in Europe were collected. Twelve of 18 centers (67%) showed a reduction in their usual transplant activity. Additionally, outpatient visits have been modified and restricted to selected ones, and the use of telemedicine tools has increased. Additionally, a total of 14 COVID-19 pediatric transplanted patients were identified at the time of the survey, including eight transplant recipients and six candidates for transplantation. Only two moderate-severe cases were reported, both in HSCT setting. These survey results demonstrate the limitations in healthcare resources for pediatric transplantation patients during early stages of this pandemic. COVID-19 disease is a major worldwide challenge for the field of pediatric transplantation, where there will be a need for systematic data collection, encouraging regular discussions to address the long-term consequences for pediatric transplantation candidates, recipients, and their families.  相似文献   
45.
46.
Abstract. The relationships among glomerular filtration rate, renal plasma flow and extracellular fluid volume were investigated in control and severely hyperglycemic (442±33 mg/dl) untreated, alloxan diabetc rats. Most of diabetic animals showed significant lower values of inulin clearance (diabetics, 0.55±0.07 ml/min·100 g; controls, 0.97±0.04) and p-aminohippurate clearance (diabetics, 2.11±0.39 ml/min·100 g; controls, 3.93±0.25). Diabetic rats exhibited reduced efficiency in tubular Na+ reabsorption, increased urinary Na+ excretion (diabetics, 3.12±0.27 mEq/day; controls, 1.25±0.14) and diminished values of plasma renin activity (diabetics, 3.34±0.44 ng/ml·h; controls, 8.64±0.79). Significant negative correlations were found between glycemia and renal hemodynamic variables. Acute overload with glucose further decreased these variables in both groups: inulin clearance in diabetics vs. controls, 0.26±0.04 vs. 0.44±0.05 ml/min·100 g; p-aminohippuric acid clearance in diabetics vs. controls, 1.09±0.20 vs. 1.55±0.21 ml/min·100 g. We conclude that chronically hyperglycemic alloxan diabetic rats showed diminished glomerular filtration rates (inulin clearance), renal plasma flow (p-aminohippurate clearance) and extracellular fluid volume associated with urinary Na+ losses and alterations in the renin-angiotensin system. Decreased reninangiotensin system activity might reduce aldosterone secretion, which in turn could result in (succesively) urinary sodium loss, extracellular fluid volume contraction and reductions in glomerular filtration and renal plasma flow.  相似文献   
47.

Background

The aim of the present study was to develop a rat model of colonic microperforation secondary to thermal injury for future studies to assess new treatments.

Methods

Twenty-four male Sprague–Dawley rats were used in this study. Hot biopsy forceps were used for all treatments. All lesions were created in proximal left colon using the soft coagulation setting. The power setting tested was 40 W, and the durations of monopolar soft coagulation application evaluated were 2, 3, and 4 s.

Results

In the acute phase, 48 h after thermal injury, durations of cautery of 2 and 3 s resulted in transmural necrosis, whereas with 4 s microperforation was obtained. In the late phase, 7 d after the damage, only duration of cautery of 4 s showed deep cautery effects, with signs of peritonitis.

Conclusions

We determined optimal power settings and duration of therapy in a rat model for producing electrocautery that involves transmural necrosis with microperforation.  相似文献   
48.
To analyse the effectiveness of optimization of biologics in rheumatoid arthritis (RA). It was a single-centre retrospective observational study from January 2009 to September 2012. The effectiveness of the optimization of TNF antagonists, tocilizumab and abatacept in RA was studied. Optimization included predefined dose down-titration and/or expansion of dose interval in early arthritis with sustained DAS28-ESR <2.6 and established arthritis with a sustained DAS28-ESR <3.2. Primary outcome was time to relapse defined as increase in DAS28-ESR greater than 20 % over baseline. Cox’s regression analysis was performed to identify predictors of relapse. Sixty-four patients were included in the study. In the survival analysis, rates of relapse were 9.8 % at 6 months, 31.4 % at 12 months and 44.6 % at 18 months. Rates of patients with an increase in DAS28-ESR > 20 % and ≥1 inflamed joint at 6, 9 and 18 months were 1.6, 17.2 and 27.1 %, respectively. In relapsing patients, mean DAS28-ESR at relapse was 3.44 (2.94–4.79) and mean DAS28-ESR following the return to the prior dose of the biologic was 2.52 (1.42–3.21). No predictors of relapse were found in multivariate analysis. Optimization of the treatment with biologics in RA is an efficacious and safe treatment option.  相似文献   
49.

Introduction

Vitamin D insufficiency (VDI) has been associated with increased cardiovascular risk in the non-HIV population. This study evaluates the relationship among serum 25-hydroxyvitamin D [25(OH)D] levels, cardiovascular risk factors, adipokines, antiviral therapy (ART) and subclinical atherosclerosis in HIV-infected males.

Methods

A cross-sectional study in ambulatory care was made in non-diabetic patients living with HIV. VDI was defined as 25(OH)D serum levels <75 nmol/L. Fasting lipids, glucose, inflammatory markers (tumour necrosis factor-α, interleukin-6, high-sensitivity C-reactive protein) and endothelial markers (plasminogen activator inhibitor-1, or PAI-I) were measured. The common carotid artery intima-media thickness (C-IMT) was determined. A multivariate logistic regression analysis was made to identify factors associated with the presence of VDI, while multivariate linear regression analysis was used to identify factors associated with common C-IMT.

Results

Eighty-nine patients were included (age 42±8 years), 18.9% were in CDC (US Centers for Disease Control and Prevention) stage C and 75 were on ART. VDI was associated with ART exposure, sedentary lifestyle, higher triglycerides levels and PAI-I. In univariate analysis, VDI was associated with greater common C-IMT. The multivariate linear regression model, adjusted by confounding factors, revealed an independent association between common C-IMT and patient age, time of exposure to protease inhibitors (PIs) and impaired fasting glucose (IFG). In contrast, there were no independent associations between common C-IMT and VDI or inflammatory and endothelial markers.

Conclusions

VDI was not independently associated with subclinical atherosclerosis in non-diabetic males living with HIV. Older age, a longer exposure to PIs, and IFG were independent factors associated with common C-IMT in this population.  相似文献   
50.
The occurrence of a hepatoduodenal ligament teratoma is extremely rare,with only a few cases reported in the literature.This case report describes the discovery of a hepatoduodenal ligament lesion revealed during abdominal ultrasonography for cholelithiasis-related abdominal pain in a 27-year-old female.Cross-sectional imaging identified a 5 cm×4 cm heterogeneous mass of fat tissue with irregular calcification located in the posterior-superior aspect of the head of the pancreas.An encapsulated lesion showing no invasion to the common bile duct or adjacent organs and vessels was exposed during laparotomy and resected.Intraop-erative cholangiography during the cholecystectomy showed no abnormalities.The postoperative course was uneventful.Pathological analysis of the resected mass indicated hepatoduodenal ligament teratoma.This case report demonstrates that cross-sectional im-aging,such as computed tomography,can reveal sus-pected incidences of this rare type of teratoma,which can then be confirmed after pathologic analysis of the specimen.The prognosis after complete surgical resec-tion of lesions presenting with benign pathological fea-tures is excellent.  相似文献   
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