Fine particulate matter (PM2.5) not only directly damages lung tissue, but also can be absorbed into blood through alveolar capillaries, which is toxic to the cardiovascular system. PM2.5 can affect lipid metabolism, endothelial function, coagulation and thrombosis through oxidative stress, inflammatory reaction, autonomic nervous dysfunction and immune regulation abnormality, so that it promote arteriosclerosis, plaque instability, and increase the morbidity and mortality of cardiovascular disease. We reviewed the effects and mechanisms of PM2.5 on arteriosclerosis, in order to provide the evidence for the studies into prevention of cardiovascular diseases caused by air pollution.

Objective To compare the dosimetric effects of systematic MLC leaf position errors on flattening filter (FF) and flattening filter-free (FFF) IMRT for nasopharyngeal carcinoma (NPC).Methods In totaly of ten patients with NPC were enrolled in the current study.FF IMRT and FFF IMRT plans were designed for each patient, and in-house software was developed to modify the corresponding MLC files.Briefly, three kinds of systematic MLC error presented with 0.5 and 1 mm magnitudes error were simulated.The modified MLC files were re-imported into IMRT plans for dose recalculation, and differences in the dosimetry trends between FF-IMRT and FFF-IMRT plans were analyzed using a dosevolume histogram.Results Upon closed MLC, the average changes in D95％ of PTV and D of parotid glands in FFF-IMRT plans were more sensitive than in FF-IMRT plans (t =3.298-4.793, P ＜ 0.05).Otherwise, when MLC are shifted in the same direction, changes in D95％of PTV, D of PGTV, PTV as well as D of left parotid gland in FFF-IMRT plans were also more sensitive (t =2.372-6.844, P ＜ 0.05), whereas average changes in D of right parotid gland presented with less sensitivity (t =-4.049,-3.378, P ＜ 0.05).Conclusions For out-of-field or large organs, FFF-IMRT plans are more sensitive to leaf position error than FF-IMRT plans.

Drug therapy is one of the efficient methods for prostate cancer treatment. However, drug resistance greatly hindered the treatment of prostate cancer patients. Herein, the mechanisms of drug resistance in prostate cancer have been exhaustively reviewed, and that can provide an alternative strategy and new targets for anti-prostate cancer therapy.

Objective:To evaluate the positive rate of the bronchodilation test (BDT) in asthmatic children with normal forced expiratory volume in 1 second (FEV 1), forced vital capacity (FVC) and FEV 1/FVC, so as to improve the recognition of the importance of the BDT test in asthmatic children with normal FEV 1, FVC and FEV 1/FVC. Methods:Children aged 5-14 who were diagnosed with asthma in the outpatient clinic of Shandong Provincial Hospital Affiliated to Shandong University from September 2018 to August 2019 and willing to receive pulmonary function and BDT examinations were enrolled.Data of pulmonary function of children with normal FEV 1, FVC and FEV 1/FVC were collected to analyze the rate of positive BDT results and the status of small airway function. Results:A total of 1 631 asthmatic children with normal FEV 1, FVC and FEV 1/FVC were enrolled in this study, including 1 414 children with normal pulmonary function and 217 children with small airway dysfunction.Fifteen minutes after the bronchodilator was inhaled, 127 children (87 males and 40 females) showed positive BDT results, accounting for 7.8%.Among these children, 62 cases (28.6%) with co-existing small airway dysfunction showed positive BDT results.The improvement rate of FEV 1 was 8.0% to 11.9% in 132 cases (8.1%). The FEV 1 before bronchodilator inhalation accounted for (98.5±10.3)% of the predicted value.Fifteen minutes after terbutaline sulfate inhalation, the improvement rate was 13.5% (12.5%, 16.2%). The improvement rates of forced expiratory flow at 50% of FVC exhaled (FEF 50, r=-0.339, P<0.01), forced expiratory flow at 75% of forced vital capacity exhaled (FEF 75, r=-0.400, P<0.01), maximum mid-expiratory flow(MMEF, r=-0.375, P<0.01) were negatively correlated with their baseline values.The improvement rate of FEV 1 was not associated with its baseline value ( r=-0.128, P=0.153), but negatively correlated with the baseline value of MMEF ( r=-0.231, P<0.01). Conclusions:BDT results are positive in some asthmatic children with normal FEV 1, FVC and FEV 1/FVC.It is recommended that BDT testing should be conducted as much as possible in the diagnosis and follow-up of children with typical or atypical asthma.In this way, the diagnosis can be confirmed and the current optimal results can be obtained.Meanwhile, small airway function testing is helpful for comprehensive assessment of asthma and its control level.

A comparative observation about histological and histochemical study were made onthe preservating methods of local ischemic kidney of dogs.The methods of this exp-eriment were divided into five groups:A.Local hypothermia;B.Hypothermic perfu-sion solution 500ml,4℃,containing Procaine 450 mg and Heparin 100 mg,infusedinto renal artery;C.Hypothermic perfusion solution 500ml,4℃,containing 20% Ma-nniton 32ml,25% MgSO_4 0.36 ml,Heparin 100 ml,infused into renal artery;D.Localhypothermia and heparin 30 mg injected into the same vessel.E.Local room tem-perature.The specimens were taken from the kidneys of the experimental dogs atvarious period after treated with every method.The results were as follows;A,D and E group presented irreversible histological changes within 4 hoursaftertreatment.Four hours later,the reaction of SDH,ATPase,AlPase werenegative.It suggested that the kidney damage was serious,as well as expressed thatthe effect of these preservating methods for ischemic kidney are not satisfactory.In B group,the histological and histochemical alteration is very light and almostreversible,during 60 days after treatment.In C group,hypothermic perfusionsolution containing Mannitol,MgSO_4 etc either during experiment or follow observa-tion for 60 days,no histological and histochemical alterations were found.It indica-ted that this method is an ideal perservating technique for ischemic kidney.

Objective To explore the effect of newly graduated nurses'(NGRNs) career adaptability on transition shock .Methods Career adapt-abilities scale ( CAAS ) and transition shock of NGRNs scale were used to investigate career adaptability and transition shock of 223 NGRNs in 6 third-rate hospitals of Hu′nan Province , and their correlation was analyzed .Results Average score of dimension of career confidence was the highest(3.61 ±0.53) in career adapt-abilities while the dimension of career control was the lowest (3.29 ± 0.74).In transition shock scale, the average of health condition was the highest (3.72 ±0.84) while the social culture and development was the lowest (3.24 ±0.76).Career adaptability of NGRNs was negatively related to transition shock (r=-0.440,-0.224,-0.258,-0.238;P<0.05).Multiple stepwise regression analysis indicated that career concern , career curiosity , career control and career confidence had significance influence on newly graduated nurses′transition shock .Conclusions Hospitals managers should focus on career concerns and control of NGRNs and take measures to improve NGRNs′career adaptability , help them finish role transition smoothly to stabilize the nursing team and improve nursing quality finally .

Objective This study was to observe the meibomian gland scores,the miss rate of meibomian,break-up time of tear film (BUT) changes after long-term wearing orthokeratolog,and to evaluate orthokeratolog impact on meibomian gland function and the stability of the tear film.Methods A prospective case-controlled study was performed.Fifty patients 98 eyes with myopia were enrolled.According to the myopia correction mode,the patients were divided into control group (24 cases) and experimental group (overnight orthokeratolog treatment) group (26 cases).All subjects were underwent the examinations sequentially as follows:evaluation of ocular surface disease symptoms using the Ocular Surface Disease Index (OSDI),lid margin and ocular surface examination by slit lamp microscrope,infrared meibomian photography and BUT.All measurements were repeated at 3 months,6 months,24-months follow-up visit.All patients signed informed consent before examination.Results After wearing orthok-contact lens for 24 months,the meibomian gland score was 4.54±1.10 and 2.29±0.75 in the experimental group and control group,respectively,the difference was statistically significant (P＜0.05).The BUT was (6.35 ± 1.52) s 24 months after wearing orthokeratolog,which was less than (9.38 ± 1.88) s in the control group,the difference was statistically significant (P＜ 0.05).The miss rate of meibomian gland was 24.39 ± 5.54 and 22.81 ± 5.23 in the experimental group and control group,respectively.There was no statistically significant difference among the the miss rate of meibomian gland between groups and within groups (all at P＞0.05).Conclusions Long-term wearing orthokeratolog has negetive effects on meibomian gland function and the stability of the tear film.

Objective: To achieve quantitative analysis of image quality parameters and establish warning and action thresholds for the on-board imaging (OBI) system of linear accelerator. Methods: The Catphan604 phantom was repeatedly scanned in the Full-Fan and Half-Fan CBCT scanning modes on a Varian EDGE linear accelerator, and the software based on Python language development in-house was utilized to analyze image quality parameters, such as CT number linearity, geometric consistency, slice thickness, spatial resolution, uniformity and low-contrast resolution. The quantitative analysis results of each image quality parameter obtained from 16 times of scanning within 16 months were normalized to the mean and the standard deviations were recorded. A run chart analysis was created to determine the warnings and action thresholds. Results: The software built in-house can quantitatively analyze the image parameters of the two scanning modes of OBI system. The low-contrast resolution of Half-Fan was better than that of Full-Fan, whereas the spatial resolution of Full-Fan was superior to that of Half-Fan. One standard deviation (1σ) was set as the warning threshold and 2 standard deviations (2σ) as the action threshold, respectively. The tolerance level of Half-Fan was smaller than that of Full-Fan. Conclusion Self-developed software enables quantitative analysis of accelerator image quality parameters, establishes warning and action tolerance of quality assurance and provides guidance for image quality assurance under image-guided radiotherapy specification.

OBJECTIVETo investigate the differentiation capability of kidney stem cells (KSCs) into renal tubular epithelial cells (RTECs).

METHODSKSCs isolated from the renal papilla of 4-week-old SD rats were co-cultured with hypoxia-exposed RTEC in induced medium (containing activin A, BMP-7, and retinoic acid) and renal epithelial cell growth medium (REGM) alternately. The KSCs cultured in MSC medium served as the control. The KSC differentiation rates in both groups were determined using flow cytometry, immunofluorescence assay and qRT-PCR.

RESULTSFlow cytometry showed a CK-18 positive rate of 6.5Percnt; in the control KSC group and of 44.2% in the induced group. Immunofluorescence assay detected the positivity for mature epithelial cell markers CK-18, E-cadherin, and ZO-1 in the induced cells. The results of qRT-PCR showed significantly increased expression of E-cadherin and AQP-1 mRNAs in the induced cells compared with the control cells (P<0.01).

CONCLUSIONRat KSCs can be induced to differentiate into RTECs in vitro.

Activins ; chemistry ; Animals ; Aquaporin 1 ; metabolism ; Bone Morphogenetic Protein 7 ; chemistry ; Cadherins ; metabolism ; Cell Differentiation ; Coculture Techniques ; Culture Media ; chemistry ; Epithelial Cells ; cytology ; Keratin-18 ; metabolism ; Kidney Tubules ; cytology ; Rats ; Rats, Sprague-Dawley ; Stem Cells ; cytology ; Tretinoin ; chemistry ; Zonula Occludens-1 Protein ; metabolism

Objective To investigate the optimal distance between the upper and lower targets in the subsection total body irradiation(TBI)using helical tomotherapy,and to analyze the dose distribution of abutment regions. Methods A total of 8 patients with acute leukemia with a height of about 120 cm were involved in the study. All patients were scanned from the calvarium to the toe by computerized tomography (CT,Siemens)with a thickness of 5 mm,and a lead wire was placed at a point 10 cm above the patella as a marker of the boundary between the upper and lower targets. The delineation of target volumes and organs at risk(OAR)was performed in the Varian Eclipse 10.0 doctor workstation. The different distances between the lead wires and the boundary of the two targets were delineated, and images were transferred to the HT workstation to design the radiotherapy planning,including Jaw width(5 cm),modulation factor(1.8),and pitch(0.43). The plans were superimposed together, and then the dose distribution in abutment regions with different target gaps was analyzed to find the optimal distance. Results When the target gap was 5 cm, the dose distribution in abutment regions was satisfactory. However,the dose was obviously insufficient when the gap was more than 5 cm;the doses in abutment regions significantly exceeded the prescribed doses when the gap was less than 5 cm. Conclusions In the subsection TBI using HT, different parameters were designed,including Jaw width(5 cm), modulation factor(1.8), pitch(0.43), and slice thickness(5 mm). The upper and lower borders of the targets should be 2.5 cm away from the lead wire,that is,a gap of 5 cm,thus avoiding the dose-related hot or cold spots in the target convergence and ensuring a safer and more accurate radiotherapy.