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In order to make polypropylene (PP) have good conductivity and insulation, as well as certain mechanical properties, silver ions were implanted into the surface of PP to explore the feasibility of forming an embedded conductive layer in this work. The experimental results show that the surface resistivity of PP reaches 0.879 MΩ/sq, dropping by 11 orders of magnitude after ion implantation, which indicates that the surface conductivity has been improved. The surface of implanted PP presents a wrinkled morphology and gaps under the scanning electron microscope (SEM), indicating that ion implantation can cause local high temperature and thereby lead to melting on the surface of the sample. For this reason, silver ions can be easily embedded below the sample surface. The energy dispersive spectrometer (EDS) characterization result shows that the penetration depth of silver ions can reach about 2.5â€"7.5 ÎĽ m. To further improve the surface conductivity of the sample, we coated carbon black on the surface of PP and then carried out ion implantation. Due to the embedding of carbon black particles, the surface resistivity of the sample further decreased by an order of magnitude, and the change with time was more stable. The results of EDS, FTIR and XRD experiments show that both carbon black and silver ions are embedded inside the surface of the samples. In summary, the method of ion implantation after coating carbon black can form an embedded conductive layer with good conductivity and stability on the surface of PP, which realizes the design concept of integrating the conductive layer and the matrix layer into an integrated layer. The embedded conductive polymer film can be prepared in this way, which serves as a new idea for the development and application of insulating materials. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To explore the role of estrogen and estrogen receptors in the migration of vascular smooth muscle cells in varicose lower-extremity veins. PATIENTS AND METHODS: Tissue samples of normal lower extremity vein (56 cases) and varicose lower extremity vein (47 cases) were collected. Western blot and real-time fluorescent qPCR were performed to measure the expression of Estrogen receptor a (ERa) in tissues. Two cell co-culture systems were established for human umbilical vein endothelial cells (HUVECs) and human umbilical vein smooth muscle cells (HUVSMCs). One system was incubated under normal oxygen conditions (normal oxygen group), and the other was under oxygen- poor conditions (hypoxia group). The two systems were treated with 10-7 mM Estrogen E2, 10-7 mM BSA-conjugated Estrogen E2-BSA, 10- 7 mM Estrogen E2+10-3 mM Tamoxifen (TAM), respectively for 24 h. The treated cells were subjected to cell scratch assay, transwell assay, and Western blot analysis of MMP2 and MMP9 protein expression. RESULTS: T he e xpression of E Ra i n varicose lower extremity vein was significantly up-regulated compared with that in normal lower extremity vein. The cell migration rate and the number of migrating cells in untreated hypoxia group and E2-treated normal oxygen group were comparable (p>0.05) to those in untreated normal oxygen group. The cell migration rate and the number of migrating cells were significantly increased (p<0.05) in E2-treated hypoxia group, compared with E2-treated normal oxygen group and untreated hypoxia group. The cell migration rate, the number of migrating cells, and expression levels of MMP2 and MMP9 were significantly decreased in E2/TAM-treated hypoxia group, compared with those in E2-treated hypoxia group. CONCLUSIONS: In summary, E2 can promote the migration of vascular smooth muscle cells and induce varicose veins of the lower extremities, which may be related to the promotion of MMP2 and MMP9 expression through the classical pathway of ER. [ABSTRACT FROM AUTHOR]

Groundwater quality in the Basin of Dhamar (Yemen) has been studied using geographic information system (GIS), principal component analysis (PCA) and correlation technique. A geographic information system is a tool for mapping and analyzing spatial data and is also used to retrieve groundwater quality information. For this study 26 wells were selected, for each well thirteen physicochemical parameters were analyzed including electrical conductivity, Calcium (Ca2+), Magnesium (Mg2+), Sodium (Na+), potassium (K+), bicarbonate (HCO3-), Chloride (Cl-), Sulphate (SO42-), Nitrate (NO3-), Iron (Fe2+), Fluoride (F-) and Total Hardness (TH). The collected groundwater was evaluated for its suitability for both drinking and irrigation purposes. Correlation and PCA have been utilized to analyze the parameters. Cartographic maps of the study area have been generated using multivariate statistical tools and GIS approach Inverse Distance Weighting (IDW) for all the above parameters. The created maps can be used to visualize, analyze, and understand the relationship among all locations. Most of the wells are found to be within the permissible limit except one well and this is due to the anthropogenic pollution received by human activities. Correlation and principal component analysis can help in selecting the most significant parameters to determine the status of water quality. The tools available in the GIS environment supported the study in the integration of data with very different data structures, i..e. point, 2D and 3D, towards spatial modeling of processes relevant to the assessment of groundwater resources. [ABSTRACT FROM AUTHOR]

1,2,3-trichloropropane (1,2,3-TCP) is commonly used as an intermediate in pesticide and an industrial specialty solvent. Acute 1,2,3-TCP poisoning is rare but a medical emergency. Sporadic cases of toxic hepatic injury from 1,2,3-TCP in humans have been reported. Liver is a target organ for 1,2,3-TCP toxicity, which may ensue in a short period after ingestion. A specific antidote against 1,2,3-TCP is not available. So it is important to distinguish that a patient with 1,2,3-TCP poisoning constitutes a medical emergency. In this case study, the poisoned patient’s clinical condition and laboratory values improved gradually after she received hemoperfusion (HP) and plasma exchange, which indicated that the therapy with HP and plasma exchange were helpful in the treatment of 1,2,3-TCP poisoning. [ABSTRACT FROM AUTHOR]

A recent seminar on public health education at the Chinese University of Hong Kong posed some key questions for the future of public health, as well as how the next generation of public health specialists should be educated. This paper summarizes some of the discussions on the future of public health education in China within the context of China's healthcare reforms and trends in global public health education. [ABSTRACT FROM AUTHOR]

Since the outbreak of the Coronavirus Disease 2019 (COVID-19), universities have carried out online education for public health and preventive medicine courses under the policy of "Suspending Classes Without Stopping Learning" launched by the Chinese government. The Public Health and Preventive Medicine Committee of the Ministry of Education Steering Committee for Medical Education investigated the online teaching activities in the member universities. This study presents the survey results, discusses the existing problems, and proposes suggestions for further reforms on mixed teaching activities.

Objective: To determine the environmental contamination degree of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in corona virus disease 2019 (COVID-19) wards, to offer gui-dance for the infection control and to improve safety practices for medical staff, by sampling and detecting SARS-CoV-2 nucleic acid from the air of hospital wards, the high-frequency contact surfaces in the contaminated area and the surfaces of medical staff's protective equipment in a COVID-19 designated hospital in Wuhan, China., Methods: From March 11 to March 19, 2020, we collected air samples from the clean area, the buffer room and the contaminated area respectively in the COVID-19 wards using a portable bioaerosol concentrator WA-15. And sterile premoistened swabs were used to sample the high-frequency contacted surfaces in the contaminated area and the surfaces of medical staff's protective equipment including outermost gloves, tracheotomy operator's positive pressure respiratory protective hood and isolation clothing. The SARS-CoV-2 nucleic acid of the samples were detected by real-time fluorescence quantitative PCR. During the isolation medical observation period, those medical staff who worked in the COVID-19 wards were detected for SARS-CoV-2 nucleic acid with oropharyngeal swabs, IgM and IgG antibody in the sera, and chest CT scans to confirm the infection status of COVID-19., Results: No SARS-CoV-2 nucleic acid was detected in the tested samples, including the 90 air samples from the COVID-19 wards including clean area, buffer room and contaminated area, the 38 high-frequency contact surfaces samples of the contaminated area and 16 surface samples of medical staff's protective equipment including outermost gloves and isolation clothing. Moreover, detection of SARS-CoV-2 nucleic acid by oropharyngeal swabs and IgM, IgG antibodies in the sera of all the health-care workers who participated in the treatment for COVID-19 were all negative. Besides, no chest CT scan images of medical staff exhibited COVID-19 lung presentations., Conclusion: Good ventilation conditions, strict disinfection of environmental facilities in hospital wards, guidance for correct habits in patients, and strict hand hygiene during medical staff are important to reduce the formation of viral aerosols, cut down the aerosol load, and avoid cross-infection in isolation wards. In the face of infectious diseases that were not fully mastered but ma-naged as class A, it is safe for medical personnel to be equipped at a high level.

Objective: To systematically evaluate the safety and efficacy of laparoscopic versus open surgery for palliative resection of the primary tumor in stage IV colorectal cancer. Methods: The databases of CNKI, Wanfang, VIP, PubMed, EMBASE and Cochrane Library were searched to retrieve randomized controlled trials (RCT) or clinical controlled trials (CCT) comparing laparoscopic surgery with open surgery for palliative resection of the primary tumor in stage IV colorectal cancer published from January 1991 to May 2019. Chinese search terms included "colorectum/colon/rectum" , "cancer/malignant tumor" , "laparoscopy" , "metastasis" , " IV" ; English search terms included "laparoscop*" , "colo*" , "rect*" , "cancer/tumor/carcinoma/neoplasm" , " IV" , "metasta*" . Inclusion criteria: (1) RCT or CCT, with or without allocation concealment or blinding; (2) patients with stage IV colorectal cancer that was diagnosed preoperatively and would receive resection of the primary tumor; (3) the primary tumor that was palliatively resected by laparoscopic or open procedure. Exclusion criteria: (1) no valid data available in the literature; (2) single study sample size ≤20; (3) subjects with colorectal benign disease; (4) metastatic resection or lymph node dissection was performed intraoperatively in an attempt to perform radical surgery; (5) duplicate publication of the literature. Two researchers independently evaluated the quality of the included studies. In case of disagreement, the evaluation was performed by discussion or a third researcher was invited to participate. The data were extracted from the included studies, and the Cochrane Collaboration RevMan 5.1.0 version software was used for this meta-analysis. Results: Four CCTs with a total of 864 patients were included in this study, including 216 patients in the laparoscopic group and 648 patients in the open group. Compared with the open group, except for longer operation time (WMD=37.60, 95% CI: 26.11 to 49.08, P <0.05), laparoscopic group had less intraoperative blood loss (WMD=-74.89, 95% CI: -144.78 to -5.00, P <0.05), earlier first flatus and food intake after surgery (WMD=-1.00, 95% CI: -1.12 to -0.87, P <0.05; WMD=-1.61, 95%CI: -2.16 to -1.06, P <0.05), shorter hospital stay (WMD=-2.01, 95% CI: -2.21 to -1.80, P <0.05) and lower morbidity of postoperative complication (OR=0.52, 95% CI: 0.35 to 0.77, P <0.05). However, no significant differences were found in time to start postoperative chemotherapy, postoperative chemotherapy rate, and mortality ( P > all 0.05). Conclusion: Laparoscopic surgery for palliative resection of the primary tumor is safe and feasible to enhance recovery after surgery by promoting postoperative bowel function recovery, shortening hospital stay and reducing postoperative complication in stage IV colorectal cancer.

The patients with hepatic alveolar echinococcosis have unapparent early symptoms due to invasive and slow growth, and the disease is usually at an advanced stage upon diagnosis, which has a poor prognosis. Early diagnosis of hepatic alveolar echinococcosis is therefore of great importance. The advances in the ultrasound techniques continues to improve the accuracy for the diagnosis of hepatic alveolar echinococcosis, and ultrasound plays a critical role in the treatment and assessment of therapeutic efficacy for hepatic alveolar echinococcosis. This paper mainly reviews the application of ultrasound in the diagnosis and treatment of hepatic alveolar echinococcosis.

Current treatments have limited effectiveness in treating tumors. The combination of multiple drugs or treatment strategies is widely studied to improve therapeutic effect and reduce adverse effects of cancer therapy. The codelivery system is the key to realize combined therapies. It is necessary to design and construct different codelivery systems in accordance with the variable structures and properties of cargoes and vectors. This review presented the typical design considerations about codelivery vectors for cancer therapy and described the current state of codelivery systems from two aspects: different types of vectors and collaborative treatment strategies. The commonly used loading methods of cargoes into the vectors, including physical and chemical processes, are discussed in detail. Finally, we outline the challenges and perspectives about the improvement of codelivery systems., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (© 2020 The Author(s).)

Objective: To evaluate the treatment of vasoproliferative tumors of the retina (VPTR). Methods: Retrospective case series study. The clinical data of 20 VPTR patients (20 eyes) were retrospectively analyzed, including 2 eyes only treated by cryotherapy, 1 eye only treated by photocoagulation and 1 eye only treated by ruthenium-106 brachytherapy. The remaining 16 eyes had combined treatment of ruthenium-106 brachytherapy, photodynamic therapy, anti-VEGF therapy, photocoagulation and cryotherapy. Nine eyes were also treated by vitrectomy because of complications such as retinal detachment and vitreous hemorrhage. Results: Single or multiple yellow white or orange red, highly vascular tumor lesions were found in ocular fundi of the 20 eyes. All eyes were accompanied by complications, including intraretinal and subretinal exudations (100%), macular edema ( n= 19, 95%), epiretinal membrane ( n= 4, 20%), retinal detachment ( n= 8, 40%), vitreous hemorrhage ( n= 6, 30%), abnormal blood vessels ( n= 16, 80%) and proliferative membrane ( n= 7, 35%). In the follow-up, the tumor in the eye treated by ruthenium-106 brachytherapy alone was atrophied and the vision improved. Regarding the 2 eyes treated by cryotherapy alone, macular edema and abnormal blood vessels decreased and visual acuity improved in 1 eye, and visual acuity did not change significantly in another eye. More leakages and increased visual acuity were found in the eye treated by photocoagulation alone. Among the 16 eyes treated with combined therapy, 9 eyes had decreased complications and improved visual acuity, 3 eyes did not change significantly, and 2 eyes had increased complications and decreased visual acuity. Conclusions: The conditions of VPTR are complex and difficult to treat. According to the specific conditions, clinicians should choose appropriate treatment methods; different treatment methods can be combined. Laser photocoagulation and cryotherapy may be chosen to treat small tumors complicated with abnormal blood vessels. Ruthenium-106 brachytherapy could treat big tumors complicated with exudative retinal detachment. Vitreous surgery can be used in hemorrhage and tractional retinal detachment. Anti-VEGF therapy is effective in the treatment of macular edema. (Chin J Ophthalmol, 2020, 56:272-278) .

To implement Healthy China 2030 Plan and Healthy China Actions (2019-2030) requires a high quality and efficient public health care system. Centers for disease prevention and control as one of the important components of the public health care system, should be critically transformed and reformed in their functions. Government needs to redefine and enforce the functions and improve assurance mechanisms for the centers to carry out the functions. The centers should strengthen their capacities for the transformed functions.

Objectives: To analyze RB1 gene mutation in retinoblastoma (RB) patients using gene capture technology. Methods: Experimental research. The clinical data of 17 RB patients were collected at Department of Ophthalmology, Peking University People's Hospital from June 2010 to Jun 2014. Peripheral blood samples of seventeen RB patients and their parents were collected and genomic DNA were extracted. DNA library from RB patients was mixed with designed gene capture probe of RB1 exons and its flanking sequences. The data were analyzed using bioinformatics software. To avoid the false positive, the abnormal sites were verified using the Sanger sequencing method. Results: Totally, there were 17 RB patients, including 12 males and 5 females, from 0.5 to 23 years old, average ages were (3.2±5.2) years old. Both eyes were involved in 6 patients. The other 11 cases were only one eye was attacked. Four RB patients were found to have germline mutations, among whom 2 had bilateral tumors and 2 had unilateral tumors. 2 novel missense mutations were identified, including 15(th) exon c.1408A>T (p. Ile470Phe) and c.1960G>C (p. Val654Leu) at 19(th) exon. No RB1 mutation was identified in any of their parents. We also identified 2 mutations reported previously. One is c.1030C>T termination mutation at 10(th) exon in a bilateral RB patients and his father, who was diagnosed with unilateral RB. The other is c.371-372delTA frame shift mutation at 3(rd) exon. No mutation was found in their parents. Conclusions: Two novel germline RB1 mutations were found using gene capture technology, which enriched RB1 mutations library. (Chin J Ophthalmol, 2017, 53: 455-459) .

Improving case detection is an urgent and serious challenge for tuberculosis (TB) control in China. We investigated the extent to which TB patients delayed seeking TB care and health services delayed reaching a diagnosis, and socio-economic factors associated with the delays. Standard questionnaires were administered to 190 new smear-positive TB patients who had completed treatment at TB dispensaries in four counties of Shandong Province in 2001. Multivariate analysis using Cox Regression showed that old age, lack of education and distance from home to a township health centre were significantly associated with delay in seeking care from service providers. In examining the delay between first contact with a service provider and diagnosis, we found that women experienced longer delays than men, and that the higher the level of facility patients first visited, the less time was needed to achieve a diagnosis. These two factors were statistically significant in multivariate Cox Regression analysis. We concluded that the elderly, the less educated, women, and those living far from health facilities face the longest delays in reaching TB services and achieving diagnosis.

Ghrelin is an acylated peptide recently identified as an endogenous ligand for the growth hormone (GH) secretagogues (GHSs) receptor (GHS-R) and is involved in a novel system for regulating GH release. To study the biological activities of ghrelin using plasmid vector administration, we constructed myogenic expression vectors containing the full length cDNA of swine ghrelin-28 (pGEM-wt-sGhln) and truncated variant (pGEM-tmt-sGhln) consisting of the first seven residues of ghrelin (including Ser3 substituted with Trp3) with addition of a basic amino acid, Lys (K) at the C-terminus. After intramuscular injection of pGEM-wt-sGhln and pGEM-tmt-sGhln, RT-PCR analysis demonstrated that the ectopic expressions of ghrelin and its variant were observed 30 days post-injection. The level of GH increased in rat serum, and was significantly higher than that of the control group 20 days post-injection with pGEM-tmt-sGhln (P < 0.05). Administration of 150 microg of pGEM-wt-sGhln and pGEM-tmt-sGhln enhanced growth in rats over 30 days and great stimulatory responses were observed at day 10 and 20 post-injection respectively, whose body weight gains were on average 15% (P < 0.05) and 21% P < 0.033 significantly heavier than controls. These results suggested that skeletal muscle might have the potential to perform post-translational acylation for ghrelin, and short ghrelin variant might have the biological effects as wild type ghrelin.

Molecular genetic polymorphisms were studied for MHC-B-LII beta(beta 1 exon) locus in ten breeds of chicken by PCR-RFLPs. Thirty-seven genotypes were detected in these chicken. In the 305 bp fragment derived from MHC-B-LII beta(beta 1 exon) locus digested with Hha I, EcoRV, HaeIII, Xba I, there were significant difference with the frequencies of genotype and combined genotype among individuals or breeds. Statistical results showed Hardy-Weinberg equilibrium in polymorphic sites were inconsistent among various breeds. Sequencing results suggested there are more polymorphism at the level of amino acid than at that of nucleotide. Furthermore, as antigen binding site, the highly polymorphisms of beta 1 exon sequence was a reflection to the antigen diversity of immune systems. Moreover, it was implied that there was highly association between genetic polymorphisms of beta 1 exon and reproduction performance in chicken.

Objective: To investigate the changes of regeneration and conduction function for peripheral nerve after neurolysis by nerve special staining and electrophysiology., Methods: Sixty Sprague-Dawley male rats were randomly divided into four groups(n = 15), four methods were designed on rats models of sciatic nerve compression. There were simple decompression as group A, internal neurolysis after decompression as group B, lemithason(0.5 mg/kg) injected in the epineurium after decompression as group C, and lemithason(0.5 mg/kg) injected around the epineurium after decompression and internal neurolysis as group D. Motor nerve conduction velocity(MNCV) and motor latency (Lan) were monitored at 1,2,3,4,5 weeks after decompression, sections were regularly taken from the previously compressed area to perform morphometric analysis., Results: After 2 weeks of decompression, the significant recovery were observed in both MNCV and Lan of four groups. Up to the 5th week of decompression, recovery of electrophysiology was significantly faster in group C and D than that of group A and B, particular in group C(P < 0.05), while group A compared with group B, there was no statistical difference in both MNCV and Lan(P > 0.05). Morphometric analysis showed that a lot of neural regeneration fibers were observed in group C and D after 3 weeks of decompression., Conclusion: Decompression can improve nerve conduction function significantly, while injection of lemithason in epineurium after decompression can promote the structure and function recovery of injured nerve.

Objective: To explore the importance of the posterior and lateral arterial network of elbow in the application of the super-regional and mutual-pedicled axial flap., Methods: Twenty-seven upper extremities of adult cadavers were prepared as casts of Acrylomintril Batradiene Styrene(ABS) resin and corroded in a strong solution of NaOH according to natural layers of human tissue. The source, site and structure of the posterior and lateral arterial network of elbow were observed, the number and total sectional area of anastomosing branches crossing the line between two humeral epicondyles were measured and compared with the medial and anterior region., Results: There are 8.64 +/- 2.74(36.42%) and 8.30 +/- 1.19(35.0%) anastomosing branches crossing the posterior and lateral regions, and total section areas are (0.48 +/- 0.11) mm2 and (0.37 +/- 0.03) mm2 respectively. So there is very rich arterial network around the elbow., Conclusion: The enough number of anastomosing branches and their section areas of the posterior and lateral region of the elbow make it possible to connect super-regional and mutual-pedicled axial flaps crossing the elbow.

Aim: To study the effect of smoking on the semen quality in infertile men in Shandong Province, China., Methods: Adult non-drinker males attending the infertility clinic, including 110 non-smokers and 191 smokers, were recruited for the study. Sixty-one fertile, non-smoker and non-drinker males, who had one or more children, served as the controls. The smokers were divided into subgroups according to the amount and duration of smoking. Semen parameters (semen volume and sperm density, viability, motility, and morphology) were examined and seminal plasma contents of Zn , Cu and superoxide dismutase (SOD) determined., Results: The semen volume and acidity, and the sperm density, viability and forward progression, as well as the seminal plasma contents of Zn, Cu and SOD were much lower in the medium, heavy and long-term smokers than in the non-smokers (P < 0.01). The sperm density, viability and forward progression, and the seminal plasma Zn, Cu and SOD levels were negatively correlated with the amount and duration of cigarette smoking (P < 0.01)., Conclusion: Medium, heavy and long-term smoking adversely affected the semen quality in a population of men visiting the infertility clinic in Shandong, China.