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1.

Background

It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.

Objective

To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5?μm (PM2.5) and the risk of metabolic syndrome in Korean adults without CVD.

Methods

Exposure to PM2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.

Results

Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m3 increase in PM2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).

Conclusion

Exposure to one-year average PM2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM2.5 affects the onset of MS and its components which may lead to increase the risk of CVD.  相似文献   
2.
《Clinical lung cancer》2020,21(5):e405-e414
BackgroundProgrammed cell death 1 (PD-1) inhibitors have become a standard treatment, albeit not completely effective, for patients with advanced non–small-cell lung cancer (NSCLC). Previous studies of advanced melanoma have revealed that the tumor burden predicted the response to PD-1 inhibitors, although this relationship has remained unclear for NSCLC.Patients and MethodsThe present single-center retrospective study evaluated 163 patients with advanced NSCLC who had received PD-1/programmed cell death ligand 1 (PD-L1) inhibitor monotherapy from December 2015 to December 2018. The clinical tumor burden was estimated using the baseline sum of the target lesions’ longest diameters (BSLDs), measured according to the Response Evaluation Criteria for Solid Tumors, and the baseline number of metastatic lesions (BNMLs).ResultsThe optimal cutoff values for predicting progression-free survival (PFS) were 5 for the BNMLs and 76 mm for the BSLDs, using the minimum P value method. The low-BNML group included 73 patients (44.8%). The median PFS was 12.2 months in the low-BNML group and 2.8 months in the high-BNML group (hazard ratio, 0.51; P = .0005). The low-BSLD group included 92 patients (56.4%). The median PFS was 9.6 months in the low-BSLD group and 3.4 months in the high-BSLD group (hazard ratio, 0.52; P = .0006). Multivariable analysis revealed that low-BSLD, low-BNML, nonsquamous histologic type and a PD-L1 tumor proportion score of ≥ 50% were independently associated with prolonged PFS.ConclusionsPD-L1 expression and the clinical tumor burden can predict the efficacy of PD-1/PD-L1 inhibitor monotherapy for NSCLC.  相似文献   
3.
Although present sonomicrometer techniques for measuring continuous changes in vascular diameter are very useful, two problems with available methods are difficulty in maintaining crystal alignment throughout an acute experiment and inability to measure absolute dimensions less than 1 mm. We have designed and ultrasonic dimension gauge system to over come these problems. The design uses a gate to pass a 20 MHz signal to a counter during the sonic travel time between crystals, and then converts the digital count to an analogue voltage. Interference from the transmitting impulse in the received signal was minimised using MOSFET transistors allowing measurements of absolute dimensions from 0.00 mm to 99.9 mm. An averaging effect which depends upon the asynchrony between the basic timer and the counter clock results in a resolution of at least 10 μm. Repeated calibration curves showed an accuracy of 2.5 μm without significant bias. Piezoelectric crystals were mounted to a lighweight stainless-steel clip to facilitate attachment to the vessel and to maintain the crystals in focus during changes in diameter. Mean and phasic diameters measured in the femoral artery with the clip device correlated well with measurements obtained with crystals sewn to the adventitia of the femoral artery of the dog (slope =0.97, r=0.99).  相似文献   
4.
A system for the direct measurement of the inner diameters of selected human arteriesin situ has been developed. Ultrasound pulses are emitted perdendicular to the vessel axis, and reflected from the wall material interfaces. Improved depth resolution is achieved by using a high-frequency transducer, and by inverse filtering of the signal. This is performed by emitting a waveform calculated beforehand to give an optimum time resolution in the received echo. Echoes from both innerand outer surfaces of the vessel walls are discriminated, and the inter-echo time intervals can be measured with an accuracy of 33ns, corresponding to approximately 26μm. By repeating the measurements through the cardiac cycle, the diameter variations can be accurately described.  相似文献   
5.
本文观察了成人尸体68具共计136侧上肢的尺侧上副动脉起源和行径,分支和分布及其管径大小。结果尺侧上副动脉多数起于肱动脉(占83.09%),口径多在1.1~2.5mm之间(占96.32%),距离胸大肌下缘31~60mm居首位,支数以3~5支多见。  相似文献   
6.
7.
AIM: To compare retinal artery-vein diameters (RAVDs) of patients with pseudoexfoliation (PSX) syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer (RNFL) thickness parameters and RAVDs. METHODS: Seventeen eyes with PSX and 17 eyes of age-matched controls were included in the study. All participants underwent routine ophthalmological examination, Humphrey visual field and RNFL examination by using Stratus OCT. Retinal images were obtained by using a retinal camera (Topcon 501X). RAVDs were measured from inferior nasal, inferior temporal, superior nasal and superior temporal arcuates by using IMAGEnet software. Superior, inferior, nasal, temporal and average RNFL thicknesses were recorded. RAVDs and RNFL parameters in groups and correlations were analyzed by Mann-Whitney U and Spearmann correlation tests. RESULTS: Only inferior quadrant and average RNFL thickness were detected thinner in the PSX group compared with control group (P=0.009, P=0.038, respectively). No statistically significant difference regarding RAVDs was found between two groups. CONCLUSION: RAVDs seems to be comparable in the PSX and control group. RNFL is thinner in the inferior quadrant in the PSX group. RNFL thickness and RAVDs show significant correlations in both groups. This correlation doesn’t seem to be specific to PSX.  相似文献   
8.
Objectives. Angiography by selective catheterization is the reference standard for coronary bypass graft patency assessment but carries a risk of serious complications. We have investigated whether 16-slice multidetector spiral computed tomography (MDCT) can substitute for selective angiography. Design. Two to three years after coronary artery bypass grafting, 45 patients with a total of 156 bypasses (100 single and 28 sequential grafts) were examined with both MDCT and conventional selective angiography on the same day. The bypasses were classified as patent, stenotic or occluded. Results. The likelihood ratio for MDCT-detected occlusion was 40, reflecting a fairly high combined sensitivity and specificity. However, 24% of the distal anastomoses could not be evaluated by MDCT, mainly because of respiratory movements, artifacts due to metal clips, and small vessel dimensions. Moreover, seven out of 117 bypasses (6%) deemed evaluable by MDCT were wrongly classified by this method. Conclusions. At present, 16-slice MDCT cannot replace selective angiography for assessment of coronary bypass graft patency since 24% of bypasses could not be evaluated by this method, and an error rate of 6% is unacceptable.  相似文献   
9.
Purpose: Enteric fever is endemic in India with Salmonella Typhi being the major causative agent. Antibiotic therapy constitutes the mainstay of management. The present study was undertaken to find the susceptibility profile of Salmonella enterica var Typhi (S. Typhi) blood isolates in a tertiary care hospital between January 2001 and December 2012. Materials and Methods: A retrospective analysis of laboratory records was carried out. Conventional blood culture method was used until 2009; from January 2010 onwards BACTEC 9240 system has been in use. Salmonella were confirmed by serotyping using group and type specific antisera. Antibiotic susceptibility was performed using the disk diffusion method. In addition 116 isolates were subjected to minimum inhibitory concentration testing for chloramphenicol, ciprofloxacin, amoxicillin and nalidixic acid (NA) using agar dilution and for ceftriaxone and azithromycin using E-strips (Biomerieux). Result: A total of 1016 typhoidal salmonellae were obtained. The predominant serotype obtained was S. Typhi (852, 83.8%) followed by Salmonella enterica var Paratyphi A (164, 16.2%). We observed a re-emergence of susceptibility to first line antibiotics and a notable decline in multidrug resistant (MDR) strains. We also found all recent isolates resistant to NA and susceptible to third generation cephalosporins and 84.5% of isolates having decreasing ciprofloxacin susceptibility using revised criteria as per Clinical and Laboratory Standards Institute 2012 guidelines. Conclusion: There has been re-emergence of susceptibility to first line antibiotics and a notable decline in MDR strains of S. Typhi. We have a very high resistance to NA and decreasing susceptibility to ciprofloxacin. Third generation cephalosporins and azithromycin seem to be effective therapeutic options. Judicious use of these antibiotics is mandatory to prevent emergence of resistant strains.  相似文献   
10.
Five anthropometric measurements, birth weight, crown-heel length, head circumference, occipito-frontal diameter, and bi-parietal diameter were recorded in a group of 174 newborn infants of various gestational ages. The material was selected to contain a relatively large number of infants with extreme birth weights and/or gestational ages. Head circumference was better correlated to gestational age than were the other four measurements. Birth weight and crown-heel length had the same degree of correlation to gestational age. The two skull diameters showed significantly lower correlations to gestational age. The confidence limits for estimating gestational age on the basis of the mean value for head circumference were ±26.1 days in this material. In SGA infants, crown-heel length and head circumference were not significantly greater than in pre-term infants of the same birth weight.  相似文献   
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