Design, simulation and application of multichannel microfluidic chip for cell migration / 生物医学工程学杂志

Cell migration is defined as the directional movement of cells toward a specific chemical concentration gradient, which plays a crucial role in embryo development, wound healing and tumor metastasis. However, current research methods showed low flux and are only suitable for single-factor assessment, and it was difficult to comprehensively consider the effects of other parameters such as different concentration gradients on cell migration behavior. In this paper, a four-channel microfluidic chip was designed. Its characteristics were as follows: it relied on laminar flow and diffusion mechanisms to establish and maintain a concentration gradient; it was suitable for observation of cell migration in different concentration gradient environment under a single microscope field; four cell isolation zones (20 μm width) were integrated into the microfluidic device to calibrate the initial cell position, which ensured the accuracy of the experimental results. In particular, we used COMSOL Multiphysics software to simulate the structure of the chip, which demonstrated the necessity of designing S-shaped microchannel and horizontal pressure balance channel to maintain concentration gradient. Finally, neutrophils were incubated with advanced glycation end products (AGEs, 0, 0.2, 0.5, 1.0 μmol·L -1), which were closely related to diabetes mellitus and its complications. The migration behavior of incubated neutrophils was studied in the 100 nmol·L -1 of chemokine (N-formylmethionyl-leucyl-phenyl-alanine) concentration gradient. The results prove the reliability and practicability of the microfluidic chip.

In vitro inactivation of SARS-CoV-2 by commonly used disinfection products and methods.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is currently a global pandemic, and there are limited laboratory studies targeting pathogen resistance. This study aimed to investigate the effect of selected disinfection products and methods on the inactivation of SARS-CoV-2 in the laboratory. We used quantitative suspension testing to evaluate the effectiveness of the disinfectant/method. Available chlorine of 250 mg/L, 500 mg/L, and 1000 mg/L required 20 min, 5 min, and 0.5 min to inactivate SARS-CoV-2, respectively. A 600-fold dilution of 17% concentration of di-N-decyl dimethyl ammonium bromide (283 mg/L) and the same concentration of di-N-decyl dimethyl ammonium chloride required only 0.5 min to inactivate the virus efficiently. At 30% concentration for 1 min and 40% and above for 0.5 min, ethanol could efficiently inactivate SARS-CoV-2. Heat takes approximately 30 min at 56 °C, 10 min above 70 °C, or 5 min above 90 °C to inactivate the virus. The chlorinated disinfectants, Di-N-decyl dimethyl ammonium bromide/chloride, ethanol, and heat could effectively inactivate SARS-CoV-2 in the laboratory test. The response of SARS-CoV-2 to disinfectants is very similar to that of SARS-CoV.

MiR-139-5p inhibits the proliferation of gastric cancer cells by targeting Regulation of Nuclear Pre-mRNA Domain Containing 1B.

Regulation of Nuclear Pre-mRNA Domain Containing 1B (RPRD1B) has been of great interest in the field of oncology in recent years. The relationship between miRNAs and RPRD1B in gastric cancer (GC) has not been adequately reported. This study was designed to screen RPRD1B-targeted miRNAs and investigate its regulatory mechanism in GC cells. Quantitative RT-PCR and in situ hybridization were used to detect miRNA expression in GC tissues. Colony formation, EdU cell proliferation assay, and flow cytometry were used to analyze the cell cycle. Database-assisted gene expression analysis revealed that RPRD1B was targeted and regulated by miRNA-139-5p in GC. miRNA-139-5p expression was higher in GC tissue than in normal tissues and significantly correlated with tumor size, pathological stage, and disease-free survival of GC (p < 0.05). MiRNA-139-5p regulates GC cell proliferation and affects the transition from G1 to S phase. It binds explicitly to the 2013-2019 sites of the 3'UTR of RPRD1B and negatively regulates RPRD1B expression. We demonstrated that the ability of miR-139-5p to regulate GC cell proliferation depends on RPRD1B. This process is accompanied by changes in Cyclin D1 protein expression. We established a miR-139-5p/RPRD1B/tumor proliferation axis in GC, which may serve as novel biomarkers and drug targets for GC.

Toilets dominate environmental detection of SARS-CoV-2 virus in a hospital

BackgroundRespiratory and faecal aerosols play a suspected role in transmitting the SARS-CoV-2 virus. We performed extensive environmental sampling in a dedicated hospital building for Covid-19 patients in both toilet and non-toilet environments, and analysed the associated environmental factors. MethodsWe collected data of the Covid-19 patients. 107 surface samples, 46 air samples, two exhaled condensate samples, and two expired air samples were collected were collected within and beyond the four three-bed isolation rooms. We reviewed the environmental design of the building and the cleaning routines. We conducted field measurement of airflow and CO2 concentrations. FindingsThe 107 surface samples comprised 37 from toilets, 34 from other surfaces in isolation rooms (ventilated at 30-60 L/s), and 36 from other surfaces outside isolation rooms in the hospital. Four of these samples were positive, namely two ward door-handles, one bathroom toilet-seat cover and one bathroom door-handle; and three were weakly positive, namely one bathroom toilet seat, one bathroom washbasin tap lever and one bathroom ceiling-exhaust louvre. One of the 46 air samples was weakly positive, and this was a corridor air sample. The two exhaled condensate samples and the two expired air samples were negative. InterpretationThe faecal-derived aerosols in patients toilets contained most of the detected SARS-CoV-2 virus in the hospital, highlighting the importance of surface and hand hygiene for intervention. FundingThe work were partially supported by the National Natural Science Foundation of China (no 41977370), the Research Grants Council of Hong Kongs (no 17202719) (no C7025-16G), and Scientific Research Fund of Jiangsu Provincial Department of Health (no S21017002).

Progress of individualized treatment in Waldenström macroglobulinemia / 白血病·淋巴瘤

Waldenström macroglobulinemia (WM) is a rare lymphoma without a curable treatment method, which is characterized by MYD88 and CXCR4 gene mutations. The study on clinical manifestations, the pathological and genomic features has led to a series of promising clinical protocols. This article reviews the safety and efficacy of drugs including alkylating agents, proteasome inhibitors, monoclonal antibodies, and Bruton tyrosine kinase (BTK) inhibitors in WM patients combined with the latest research of the individualized treatment for WM at the 59th American Society of Hematology (ASH) Annual Meeting, so as to analyze the feasibility of basic genomic treatment and current integrated regimens for WM.

Application of TBL and PBL in clinical teaching of laparoscopic surgery in general surgery / 中华医学教育探索杂志

Objective To explore the application of team-based learning (TBL) and problem-based learning (PBL) method in clinical teaching of laparoscopic surgery in general surgery. Methods 48 students of surgery in our department were selected as the subjects to conduct the clinical teaching study. These students were divided randomly into two groups. The experimental group (24 students) adopted the method that combined TBL and PBL method, while the control group (24 students) adopted the traditional teaching method. We compared the efficacy of two groups in term of theoretical knowledge, surgical practice, com-prehensive surgical grade, and questionnaire survey. Results The score of theoretical knowledge and sur-gical practice on clipping soybean and making suturation and instrumental tie of two groups were obviously higher than that before teaching. After finishing teaching, the score of experimental group on theoretical knowledge, making suturation and instrumental tie and comprehensive surgical grade were higher than that of control group. The score of clipping soybean was similar between two groups. In addition, in term of questionnaire survey on the consciousness of independent study, the depth and width of study, and satisfac-tions to teaching, the TBL and PBL group had a better score than the control group. Conclusion The new teaching method which combines TBL with PBL enhances the teaching effect on theoretical knowledge and laparoscopic surgery practice. It is an effective method to train medical students.

On the development and strategy of translational medicine at hospitals / 中华医院管理杂志

Translational medicine has been on the rise for 20 years as a new model of biomedical research,which plays a positive role in narrowing the gap between basic research and clinical medicine and in development of medical sciences.This paper traced back the milestones of translational medicine,and analyzed the hurdles for China to develop translational medicine,namely the organization system,management model and benefit sharing.On such basis,the authors recommended on the development and strategy,especially in clinical medical institutions in China.

Valproic acid enhances myeloma cell sensitivity to natural killer cell-mediated lysis and its mechanism / 白血病·淋巴瘤

Objective To investigate the effect of valproic acid (VPA) on NKG2D-ligand expression in ARK,OPM2 human myeloma cell lines and their sensitization to natural killer (NK) cell-mediated Killing.Methods Different concentrations of VPA from 0-5.0 mmol/L were used to treat ARK,OPM2 cells respectively,then the cell viabilities were tested by flow cytometry (FCM).Real-time quantitative-PCR and FCM were used to detect the changes in mRNA,protein levels of NKG2D-ligand respectively in the two cell lines treated with 1 mmol/L VPA for 48 hours.The calcein-release-assay (CARE-LASS) was carried out to detect cytotoxic changes of NK cells against mydoma cells after VPA treatment.Results VPA induced the expression of MICA/B,ULBP2 (P ＜ 0.05) and in turn enhanced the NK cytotoxicity on myeloma cells.The enhancing effect of VPA was blocked by NK cells pretreated with anti-NKG2D mAb (P ＜ 0.05).The primary mechanism of NK cell killing of myeloma cells was perforin/granzyme-mediated.Conclusion VPA can induce the expression of MICA/B,ULBP2 in ARK,OPM2 cells,thereby enhancing the cytotoxicity against myeloma cells,which implies a new mechanism of anticancer approach and may be a new approach in myeloma immunotherapy.

Influences of different tube voltages on the dose and image quality of a full field digital mammography / 中华放射学杂志

Objective To evaluate the effect of different tube voltages on the radiation dose and image quality of a full field digital mammography system.Methods Both experiments were performed under manual exposure mode.In one experiment,the tube voltages were kept constant at 25,28 and 31 kVp,and the CIRS 015 phantom was exposed at three target/filter combinations molybdenum/molybdenum (Mo/Mo),molybdenum/rhodium (Mo/Rh),and rhodium/rhodium (Rh/Rh) and at tube current-exposure time products of 32-140mAs.The entrance skin exposure (ESE) and average glandular dose (AGD) were recorded,the signal-to-noise ratio(SNR) and contrast-to-noise ratio (CNR) and figure of merit (FOM) were measured to evaluate the influences of different tube voltages on dose and image quality at same target/filter combination.The univariate of randomized completed block-design was used for statistics.In second experiment,the phantom were exposed using Mo/Rh combination when the tube current-exposure time product was kept constant at 56 mAs,and the tube voltage varied between 23 and 33 kVp in 1-kVp increments.The ESE and AGD were recorded,the SNR,CNR and FOM were measured for plotting the curves against tube voltages.Results At Mo/Mo combination,the AGD,ESE,SNR,CNR and FOM of 25,28 and31 kVp were(1.25 ±0.56) mGy,(6.46±2.86) mGy,71.52±8.37,1.91 ±0.26,3.21 ± 0.68; (1.94 ±0.85) mGy,(9.18±4.07) mGy,144.46 ± 11.31,2.41 ±0.28,3.37 ±0.96 and (3.01 ±1.38) mGy,(12.60±5.59) mGy,128.89 ±15.29,2.47 ±0.31,2.31 ±0.76 respectively; at Mo/Rh combination were (1.23 ±0.55) mGy,(5.26 ±2.33) mGy,67.31 ±4.11,1.82 ±0.19,3.01 ± 0.82; (1.86 ±0.84) mGy,(7.57 ±3.34) mGy,139.54 ± 12.16,2.30 ±0.25,3.23 ±0.92 and (2.81 ±1.24) mGy,(10.48 ±4.62) mGy,127.77 ±15.14,2.59 ±0.31,2.67 ±0.68; and at Rh/Rh were(1.09 ±0.48) mGy,(4.89 ±2.16) mGy,67.46 ±2.23,1.48 ±0.72,3.08 ± 1.69; (1.75 ± 0.78) mGy,(6.88 ±3.03) mGy,137.74 ± 14.65,2.37 ±0.26,3.62 ± 1.07 and (2.59 ± 1.13) mGy,(9.32 ± 4.12) mGy,117.91 ± 19.05,2.51 ± 0.31,2.74 ± 0.84.Both experiments indicated that,for a given target/filter combination,the AGD,ESE and CNR increased,but the ESE/AGD decreased with the tube voltage increasing; The first experiment indicated both SNR and FOM of 28 kVp were higher than that of 25 kVp and 31 kVp; the second experiment showed both SNR and FOM decreased with tube voltages increasing.The differences of AGD、ESE、ESE/AGD、SNR、CNR and FOM among the three tube voltages were significant (F =4.391-528.848,P ＜ 0.05) ; but the difference of CNR between 28 and 31 kVp at Mo/Mo and Rh/Rh had no statistical significance (P ＞ 0.05) ; and the differences of FOM between 25 and 28 kVp at the three target/filter combinations were not statistically significant (P ＞ 0.05).Conclusion For a breast with 4.2 cm thickness and 50％ adipose 50％ glandular composition,different tube voltages have significant effects on the radiation dose and image quality.

The study on AHI, LSaO2 and ET-1 in patients with obstructive sleep apnea-hypopnea syndrome after H-UPPP / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore the treatment effect of H-UPPP on patients with obstructive sleep apnea hypopnea syndrome (OSAHS).@*METHOD@#Seventy-nine patients were enrolled in our study. Among which 49 patients were done with H-UPPP, and the other 30 patients were done with UPPP. AHI and LSaO2 were monitored by polysomnography and plasma endothelins-1 were tested with enzyme linked immunosorbent assay (ELISA) before and after operation.@*RESULT@#Forty-one patients were improved with reduced snoring and daytime sleepiness one year after operation in H-UPPP group,and the overall efficiency was 83.7%. Twenty-six patients were improved with reduced snoring and daytime sleepiness one year after operation in UPPP group, and the overall efficiency was 86.7%. There were significant differences of AHI, LSaO2 and ET-1 before and after operation between the two groups. Negative correlation was showed between AHI and LSaO2, also between LSaO2 and ET-1.@*CONCLUSION@#Both H-UPPP and UPPP were proved to be effective to patients with OSAHS. The perioperative complications with H-UPPP was less than UPPP.

Quality Standard of Danqitong Tablets / 中国药房

OBJECTIVE:To establish the quality standard of Danqitong tablets.METHODS:Salvia miltiorrhiza and Ra-dix Astragali in the formulation were identified qualitatively by TLC,and the contents of total saponins and tanshinone-Ⅱ A in the tablets were determined by visible ultraviolet spectrophotometry and HPLC,respectively.RESULTS:The TLC spots of Salvia miltiorrhiza and Radix Astragali were clear and well-separated.The linear ranges of total saponins and tanshinone-Ⅱ A were 0.056～0.12 mg?mL-1(r=0.999 3)and 0.002 019～0.032 13 mg?mL-1(r=0.999 9),respectively,and the average recovery rates were 97.61%(RSD=2.10%)and 95.74%(RSD=1.93%),respectively.CONCLUSION:The established standard is applicable for the quality control of Danqitong tablets.

Improvement of the Formulation of Clarithromycin Dispersible Tablets / 中国药房

OBJECTIVE:To obtain an optimum formulation of clarithromycin dispersible tablets METHODS:The preparation process was set by way of screening formulation and a formula with substitution of LS-HPC for starch was adopted RESULTS:The results showed that the substitution of LS-HPC for starch was the most preferable formulation The hardness and the friability of the tablets were improved The external apperance of unfilled corner and torn edge of the unimproved tablets was resolved CONCLUSION:Modified formulation is favorable for improving the quality of the product

Autopharmacotherapy and Guarding Against the Risk / 中国药房

OBJECTIVE:To comprehensively understand autopharmacotherapy.METHODS:The benefits and risk factors of autopharmacotherapy were analysed and the countermearsure against its risk were put forward.RESULTS&CONCLU?SION:OTC medication is safe and effective in acurate use of route dosage,but in autopharmacotherapy,there are risks as a result of influence of various factors.The safety of OTC medicines should be the matters of common concern of patients,physicians and pharmacists,and a safety mornitoring system for OTC should be established.