Quantitative risk assessment of occupational exposure to PCDD/Fs in the waste incineration industry / 中华劳动卫生职业病杂志

Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.

Mechanism of Artesunate in Reversing Epithelial-mesenchymal Transition and Akt /Snail Signaling Pathway in Colorectal Carcinoma / 中国实验方剂学杂志

Objective:To investigate the effects of artesunate （ART） on epithelial-mesenchymal transformation （EMT） of colorectal cancer HCT-8 cells，and explore the effects of ART on cell migration，invasion，EMT ability， and protein kinase B （Akt）/Snail signaling pathway of colorectal cancer. Method:3-（4-5-Dimethylthiazol-2-yl）2，5-diphenyltetrazolium bromide （MTT） assay was used to detect the effects of ART at different concentrations on the proliferation of HCT-8 cells. Wound healing assay and Transwell assay were used respectively to detect the effects of ART on migration and invasion of colorectal cancer cells. The effects of different concentrations of ART on the distribution of EMT-related proteins vimentin and E-cadherin in HCT-8 cells were detected by double-immunofluorescent staining. The effects of ART on protein expression levels of EMT markers E-cadherin，vimentin and N-cadherin in HCT-8 cells and the expression of Akt1， p-Akt1， and Snail1 in the Akt/Snail signaling pathway were determined by Western blot. Result:The dose-dependent inhibitory effects of ART on the proliferation of HCT-8 cells were determined and the inhibition rate was calculated. A dose-response curve was plotted accordingly. The half-maximal inhibitory concentration （IC₅₀） of ART on HCT-8 cells was （16.67±1.95） μmol·L^-1. The following four groups were set up： a control group （0 μmol·L^-1），and low-， medium-， and high-dose ART groups（2， 10， 50 μmol·L^-1）. Compared with the results in the control group，ART inhibited the migration and invasion of HCT-8 cells（<italic>P</italic><0.05）. Specifically， the expression of E-cadherin in HCT-8 cells was significantly up-regulated，and that of vimentin and N-cadherin was significantly down-regulated （<italic>P</italic><0.05）. The expression levels of p-Akt1 and Snail1 were significantly decreased after ART treatment，thus inhibiting EMT（<italic>P</italic><0.05）. Conclusion:The findings of this study suggested that ART inhibited the EMT-triggered migration and invasion of HCT-8 cells presumedly by inhibiting the activation of the Akt/Snail pathway to reverse EMT.

Investigation on knowledge, attitude and practice of Shanghai Jinqiao Town's recent international travellers and domestic residents towards COVID-19 / 上海预防医学

Objective To understand the cognition，attitude and awareness on the prevention and control of COVID-19 among recent international travellers back to China（hereinafter referred to as the inbound group）and local residents（domestic group），and to provide scientific evidence for further prevention and control of the epidemic. Methods Using a questionnaire website，a questionnaire entitled “Investigation and analysis of residents’ knowledge，attitude，and practice on COVID-19”was prepared，with the targeted population of the survey being international travelers back to China and local residents who had been quarantined at home for 14 days in Jinqiao Town. Cluster sampling was used to conduct the survey through WeChat. The two groups were then compared using chi-square test by using SPSS 23.0. Results Between the two groups，the awareness on the respiratory droplet transmission and inactivation effectiveness by alcohol，peracetic acid and ultraviolet ray on the SARS-CoV-2 were statistically different（P < 0.05）. In the attitude towards prevention and control measures，there was significant difference between the two groups in selecting prevention and control plans for the whole population during the outbreak（P < 0.05）. In the comparison of behavior，there was a statistical difference between the two groups（P < 0.05）whether to maintain a distance of more than 1 meter in social communication. Regarding the choice of quarantine methods（stay-at-home，intensive quarantine and no quarantine），the difference between two groups was statistically significant（P < 0.05）. Conclusion In terms of the knowledge of COVID-19，attitude towards prevention and control measures，and their own behavior，there are some differences between the inbound group and domestic group.

Silencing GFAP gene regulates the proliferation and apoptosis of high glucose-induced retinal microvascular endothelial cells / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To investigate the effect of silencing glial fibrillary acidic protein gene(GFAP)on proliferation and apoptosis of high glucose-induced human retinal microvascular endothelial cells(hRMECs)and its mechanism.<p>METHODS: Expression of GFAP in hRMECs treated with high sugar(30mmol/mL)and low sugar(5mmol/mL)was detected by qRT-PCR. The high glucose-induced hRMECs cells of silencing GFAP gene was established by lentiviral-mediated method. High glucose-induced hRMECs cells were treated with SRI-011381(TGF-β signaling pathway activator)and dimethyl sulfoxide(DMSO); Expression of GFAP, transforming growth factor-1(TGF-β1), activating transcription factor2(Smad2), Smad3 proteins were measured by Western blot, and cell proliferation and apoptosis were detected by CCK-8 and flow cytometry, respectively.<p>RESULTS: Expression of GFAP was significantly increased in high glucose treated hRMECs. The high glucose induced hRMECs cell model of GFAP gene silencing was successfully constructed by lentivirus mediation, and the cell proliferation ability was significantly improved, the apoptosis rate is significantly inhibited, and expression of TGF-1, Smad2 and Smad3 proteins in the TGF-β signaling pathway was significantly inhibited after silencing GFAP, while activation of TGF-β signaling pathway could reverse the inhibitory effect of silencing GFAP on the proliferation and apoptosis in high glucose hRMECs.<p>CONCLUSION: Silencing GFAP gene can promote the proliferation of high glucoseinducedhuman retinal microvascular endothelial cells and inhibit cell apoptosis,the mechanism may be related to the inactivation of TGF-β signaling pathway.

Intramuscular injection of estradiol combined with bone marrow mesenchymal stem cell transplantation for spinal cord injury / 中国组织工程研究

BACKGROUND: Even though estrogen can prevent secondary spinal cord injury, exert a neuroprotective role, and inhibit apoptosis in mesenchymal stem cells in vitro,little is reported on the combined use of estrogen and bone marrow mesenchymal stem cells(BMSCs)in the treatment of spinal cord injury. OBJECTIVE: To investigate the effects and mechanism of s intramuscular injection of estradiol combined with BMSCs in the treatment of spinal cord injury. METHODS: One hundred and forty-four Sprague-Dawley rats were randomly divided into four groups: combined group, BMSCs group, estradiol group and control group. After the establishment of spinal cord injury model, the rats were given intramuscular injection of estradiol 250 μg/kg estradiol combined with 6×106BMSCs (60 μL), BMSCs, estradiol or PBS in different groups, respectively. After transplantation, related indicators were detected. RESULTS AND CONCLUSION: At 1 and 4 weeks after modeling, the behavioral scores in the combined group were significantly higher than those in the other three groups (P < 0.05). At 3 and 7 days after transplantation, superoxide dismutase levels in the combined group were significantly higher than those in the other three groups, but the malondialdehyde levels were lowest in the combined group (P < 0.05). At 3 and 7 days after transplantation, the apoptotic rate in the spinal cord tissues was significantly lower in the combined group than the other three groups (P < 0.05). To conclude, estradiol can alleviate secondary cell apoptosis and inhibit oxidative stress after spinal cord injury, which contributes to the spinal motor function recovery after BMSCs transplantation.

Application of ophthalmic ultrasonography in DR / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the value of ultrasonography in diabetic retinopathy ( DR) .?METHODS: Totally 103 cases ( 103 eyes ) of type 2 diabetes mellitus were selected from May 2015 to May 2017 in our hospital, there were 32 patients 32 eyes with non diabetic retinopathy ( NDR) , 40 patients 40 eyes with non proliferative diabetic retinopathy ( NPDR ) , and 31 patients 31 eyes with proliferative diabetic retinopathy (PDR), 40 healthy volunteers (40 eyes) were selected as control group, the maximum systolic blood flow velocity ( PSV ) , end diastolic velocity ( EDV ) and resistance index (RI) of the central retinal artery (CRA), posterior ciliary artery ( PCA ) and ophthalmic artery ( OA ) were detected by color Doppler ultrasound.?RESULTS:The difference of PSV, EDV and RI of CRA, PCA and OA in each group was statistically significant (P<0. 05). The PSV of CRA, PCA and OA in NDR group were 12. 38 ± 2. 10cm/s, 13. 36 ± 2. 55cm/s and 32. 04 ± 6. 07cm/s, significantly higher than that of NPDR group (9.70±1.67cm/s, 12.20±2.01cm/s and 27.40±4.32cm/s) and PDR group ( 7. 13 ± 1. 40cm/s, 10. 31 ± 1. 82cm/s and 22.10±3.51cm/s) (P<0. 05). EDV were 4. 67±1. 20cm/s, 5. 61 ± 1. 25cm/s and 8. 40 ± 1. 51cm/s, significantly higher than that of NPDR group (3. 52±1. 19cm/s, 5. 01±1. 30cm/s and 6.61±1. 67cm/s) and PDR group (2. 48±1. 02cm/s, 4. 11±1.04cm/s and 4. 01±1. 52cm/s) (P<0. 05). And RI were 0. 63 ± 0. 07, 0. 60 ± 0. 04 and 0. 77 ± 0. 05, was significantly lower than that of NPDR group (0. 72±0. 06, 0. 67±0. 05 and 0. 81 ± 0. 03) and PDR group (0. 80 ± 0. 09, 0. 74±0. 06 and 0. 86±0. 04) (P<0. 05).?CONCLUSION: Color Doppler ultrasound monitoring the hemodynamic changes of ocular blood vessels in diabetes can provide evidence for early detection of diabetic retinopathy.

Effects of 25 Gy gamma-ray irradiation on the expression of CD62p in manually enriched human platelets / 中国实验血液学杂志

This study was purposed to investigate the effects of 25 Gy gamma-ray irradiation on the CD62p expression, platelet count and the mean platelet volume (MPV) of manually enriched platelet suspension in different time of shelf life at 22 degrees C. Each of 16 bags with plasma-rich platelet was divided into two bags, one of which was exposed to 25 Gy gamma-ray of 137Cs and the other ones was not exposed. 16 bags then were preserved for 72 hours according to AABB standards. The irradiated platelets were regarded as the observation group, and the other ones were regarded as the control group, the expression of p-selectin (CD62p) in the above 2 groups was detected by flow cytometry before irradiation and at 24, 72 hours after irradiation respectively; at the same time, the platelet count and MPV were assayed by using blood cell counter. The results showed that the expression level of CD62p on platelet in irradiated and control groups increased along with the prolonging of preservation time, the expression rate of CD62p on the platelets preserved for 24 hours was higher than that on fresh platelets with significant difference (p<0.05); the expression rate of CD62p on the platelets preserved for 72 hours obviously was enhanced as compared with platelets preserved for 24 hours (p<0.01). There were no significant differences in CD62p expression rate, platelet count and MPV between irradiated and control groups preserved for 24 and 72 hours (p>0.05), however the MPV of irradiated and control groups preserved for 72 hours was higher than that of fresh platelets (p<0.05). It is concluded that the gamma-ray irradiation does not affect the quantity and quality of platelets, but the preservation time for manually enriched platelet suspension should be shortened as far as possible.

Risk factors for postoperative delirium in patients after vascular free flap reconstruction performed under general anesthesia / 中华麻醉学杂志

Objective To investigate the risk factors for postoperative delirium in patients after vascular free flap reconstruction performed under general anesthesia.Methods Two hundred and sixteen ASA Ⅰ-Ⅲ patients aged 18-80 yr undergoing vascular free flap reconstruction surgery were enrolled in this study.Patient characteristics before and during operation were recorded.The patients were followed up for 5 days after operation.Their level of consciousness,severity of pain and sleep quality were evaluated daily.The patients were divided into 2 groups according to the occurrence of delirium during the 5 days after operation:delirium group and non-delirium group.The method of CAM-ICU was reed in the diagnosis of postoperative delirium.Multivariate logistic regression was used to analyze the risk factors for postoperative delirium.Results logistic regression analysis showed that old age,history of alcohol abuse and sleep diacrder after operation were risk factors for delirium developed after free flap surgery.Conclusion Old age,history of alcohol abuse and sleep disorder after operation were the risk factors for postoperative delirium in patients after vascular free flap reconstruction performed under general anesthesia.

Screening, Identifying and Function Analysis of Polyketide Synthase I Cluster from the Environmental Strain X-2 Which Produce Macrolactins / 微生物学通报

Macrolactins are 24-membered macrolides produced by unidentified marine bacterium, Actinomadura sp. and Bacillus sp., which exhibit both antibacterial and antitumor activities in vitro. The environmental strain X-2 which was isolated from the sediment of the East China Sea produce Macrolatin A, B and O. In this study, a set of degenerate oligonucleotide primers, designed for amplification ketosynthase(KS) domains, had been employed to identify KS gene fragments of the X-2 DNA samples. One 645 bp KS fragment(GenBank accession no. EF486351)had been cloned and used as a probe to screen the genome DNA fosmid library of X-2. Three positive clones were selected and sequenced, Homologous analysis and the function prediction of the obtained PKS gene fragments suggested that macrolactin is the Polyketide Biosynthesis Product of the gene cluster obtained in the environmental strain X-2.

Separateness and Directional Adipocyte Differentiation of Murine Bone Marrow Mesenchymal Stem Cells / 中国康复理论与实践

@#ObjectiveTo establish separate and appraisal methods of murine bone marrow mesenchymal stem cells (MSCs) and optimize the suitable conditions inducting MSCs directional differentiating into adipocytes in vitro.MethodsThe differential adherence to plastic was employed to separate MSCs. CFU-f and successive CFU-f cultures were employed to characterize the potent of proliferation and self-renewal of MSCs. The different adipogenic medium was used as induction for the differentiation of MSCs into adipocytes. The differentiated cells were identified by oil red O immunohistochemistry stain.ResultsThe purified MSCs showed the morphology of fibroblasts. It was found that the number of CFU-f formation depended on the planted number of MSCs. It showed a good relationship. Small type colony of CFU-f had little potent to re-clone, but almost 90% big type colony of CFU-f had the potent to regenerate CFU-f. The MSCs could directionally differentiated into adipocytes induced by different adipogenic medium. But more than 96% MSCs differentiated into mature adipocytes when induced by combined with dexamethasone (DM), 1-methy-3-isobutylxanthine (IBMX), insulin (IS) and indomethacin (ID).ConclusionThe purified MSCs can be harvested by method of differential adherence to plastic, and these MSCs have the potent of proliferation and self-renewal. Moreover, more than 96% MSCs can differentiate into mature adipocytes when induced by combined with DM, IBMX, IS and ID.

Relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between condylar marrow signal abnormalities and temporomandibular joint internal derangement (TMJID).</p><p><b>METHODS</b>Oblique sagittal T1 weighted MR imaging at closed and open mouth and Oblique sagittal T2 weighted MR imaging at closed mouth were obtained from 88 joints of 44 patients suffering from TMD. Condylar marrow signal abnormalities were reviewed and classified into bone marrow edema pattern (hypointense T1, hyperintense T2), sclerosis pattern (hypointense T1 and hypointense T2) and combined edema and sclerosis pattern.</p><p><b>RESULTS</b>Of 88 joints, 13 (14.8%) joints showed condylar marrow signal abnomalities, among which 11 belonged to edema pattern and, 1 was sclerosis pattern and the other was the combined patten. Of 13 joints with condylar marrow signal abnomalities, 11 (84.6%) had TMJID. Of 75 joints with normal marrow signal, 25 (33.3%) joints had TMJID. There was significant correlation between condylar marrow signal abnormalities and TMJID (P < 0.05).</p><p><b>CONCLUSION</b>Disc displacement is one of the factors inducing condylar marrow signal abnormalities. The pathological process from disc displacement to osteonecrosis requires further study.</p>

Expression of Tumstatin_(183-230)-TRAIL fusion protein and identification of its biological functions / 第二军医大学学报

Objective:To express Tumstatin_(183-230)-TRAIL fusion protein and to observe its biological functions.Methods: SOE-ing PCR was employed to amplify the recombinant sequence of Tumstatin_(183-230)and TNF-related apoptosis-inducing ligand (TRAIL_(114-281)).An expression vector pMAL-Tu-T was constructed by inserting Tu-T sequence into pMAL-c_2;the vector was used to transfect E.coli BL21(DE3)and expression of MBP-Tu-T fusion protein was induced by IPTG.Amylose Resin columns were employed to purify the fusion protein.The biological functions of MBP-Tu-T protein was examined by inhibitory test of endothelial cell proliferation,standard tumor cell cytotoxic assay,in vitro tube formation inhibition,and electron microscopic observation(apoptosis).Results:The expression rate of MBP-Tu-T fusion protein in E.coli was about 20%. Purified recombinant protein obviously inhibited endothelial cell proliferation(IC_(50)12.5?g/ml),induced apoptosis of pancreatic cancer cells,and inhibited tube formation.Conclusion:Constructed MBP-Tu-T fusion protein is bifunctional,which lays a solid foundation for further investigation of antitumor effect of Tumstatin_(183-230)-TRAIL in vivo.