[System analysis of the ecological distribution of bacteriophages in hospital wastewater].

Phage therapy is one of the most important tools for the treatment of infections with multi-drug resistant bacteria. Such phages are usually isolated from hospital effluents, however, no systematic study on the distribution of phages in hospital effluents has been conducted so far. The aim of this study was to isolate the corresponding phages of common pathogenic bacteria isolated in the clinic as hosts, so as to assess the ecological distribution of phages in hospital wastewater and to provide a reference for the isolation and application of phages of drug-resistant bacteria in the clinic. A cross-sectional study design was used in this study. The 125 pathogenic bacteria (belonging to 16 different strains) isolated from the clinical microbiology laboratory of Qilu Hospital of Shandong University from May to June 2023 were selected as the target strains, and the phages corresponding to these strains were isolated and purified from the hospital wastewater by using the double-layer plate sandwich method. At the same time, the distribution of pathogenic bacteria in the same batch of wastewater was analyzed with the help of mNGS sequencing technology, so as to preliminarily investigate the abundance correspondence between pathogenic bacteria and phages in wastewater. The results showed that a total of 56 phage strains were isolated from 125 clinical pathogens as hosts, corresponding to six pathogens, including Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. All six pathogenic bacteria contained strains with different degrees of drug resistance, with a higher percentage of multi-drug resistant strains in A. baumannii, Escherichia coli and P. aeruginosa. The phage acquisition rates of these six pathogens were, in descending order, Escherichia coli (80%), Stenotrophomonas maltophilia (75%), Pseudomonas aeruginosa (70%), Klebsiella pneumoniae (66.67%), Acinetobacter baumannii (36.36%) and Staphylococcus aureus (12.5%). Preliminary mNGS sequencing results showed that the pathogenic bacteria with higher abundance in the batch of effluent were Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, Acinetobacter baumannii, Klebsiella aerogenes, Klebsiella michiganensis and Pseudomonas aeruginosa. In conclusion, phages of most common clinical Gram-negative pathogens were isolated from hospital wastewater with high isolation rates; however, phages of Gram-positive pathogens were isolated at lower rates, and only phages corresponding to Staphylococcus aureus were isolated in this study. The corresponding mNGS sequencing results showed that the distribution of Gram-negative pathogens in sewage may had a positive correlation with the ecological distribution of phages.

[Efficacy and safety of different nerve block methods for the treatment of pudendal neuralgia].

Objective: To identify efficacy and safety of pudendal nerve block in tubing through the third posterior sacral foramen for the treatment of pudendal neuralgia (PN). Methods: A retrospective study with 222 PN patients was conducted in the Department of Pain Management of Beijing Tsinghua Changgung Hospital from January 2020 to April 2023. These patients were divided into two groups based on their treatment methods: pudendal nerve block in tubing through the third posterior sacral foramen (observation group, n=101) and ultrasound-guided pudendal nerve block (control group, n=121). Primary outcome measure was the 90-day postoperative pain relief rate. Secondary outcome measures included visual analog scale (VAS) at 1, 7, 14, 30 and 90 d after surgery, the incidence of tramadol uses after surgery, postoperative self-rating anxiety scale (SAS) scores and the incidence of adverse events. Factors that influenced pain relief within 90 days after surgery were analyzed by using binary logistic regression analysis. Results: Observation group included 34 males and 67 females, aged (49.8±16.0) years old. Control group included 38 males and 83 females, aged (43.7±14.0) years old. The 90-day postoperative pain relief rate of the observation group patients was 38.6% (39/101), which was higher than the 24.0% (29/121) of the control group patients (P=0.018). Both the observation group and the control group showed an interaction effect of time and group after treatment for VAS scores (both P<0.05). In intra-group comparison, the VAS scores at 1, 7, 14, 30 and 90 d after treatment in both groups were lower than those before treatment (all P<0.05). In inter-group comparison, the differences of the VAS scores were not statistically significant in the observation group compared with those in the control group at 1, 7, 14, 30 and 90 d after surgery (all P>0.05). The SAS score of the observation group at 90 d after surgery was 51.5±6.2, which was lower than the 53.4±5.8 of the control group (P=0.022). There was no statistically significant difference in the incidence of postoperative tramadol uses and adverse events between the two groups (both P>0.05). Pudendal nerve block in tubing through the third posterior sacral foramen was a protective factor for pain postoperative relief in PN patients at 90 d after surgery (OR=1.92, 95%CI: 1.05-3.48, P=0.033). Conclusion: Pudendal nerve block in tubing through the third posterior sacral foramen is a safe and effective minimally invasive treatment. It has a higher postoperative pain relief rate within 90 d after surgery, without increasing the uses of postoperative rescue analgesics and the incidence of adverse events.

[Investigation and analysis of prevalence of musculoskeletal diseases among interventional surgeons in some top three hospitals in Tianjin].

Objective: To analyze the prevalence and risk factors of musculoskeletal diseases among interventional surgeons in top three hospitals, and to provide suggestions for prevention of musculoskeletal diseases. Methods: In June 2022, a self-designed questionnaire was used to collect general information of doctors engaged in interventional surgery (121) and non-interventional surgery (124) in some top three hospitals in Tianjin. The standard version of the Nordic Musculoskeletal Questionnaire was used to investigate information related to musculoskeletal diseases. The prevalence and risk factors of musculoskeletal diseases among interventional and non-interventional surgeons were analyzed. Results: The prevalence of musculoskeletal diseases among interventional surgeons and non-interventional surgeons was 59.50% (72/121) and 62.90% (78/124) . Compared with non-interventional surgeons, interventional surgeons had a higher prevalence of musculoskeletal diseases in the shoulders and upper back, and a lower prevalence of musculoskeletal diseases in the waist. The differences were statistically significant (P<0.05) . Multivariate logistic regression analysis showed that age, weekly time of physical exercise, time of intervention operation, and wearing protective clothing were independent risk factors for musculoskeletal diseases (P<0.05) . Conclusion: The prevalence rate of musculoskeletal diseases among doctors engaged in interventional surgery is relatively high in some top three hospitals in Tianjin, and proper enhancement of physical exercise and shortening of interventional time are conducive to reducing musculoskeletal diseases.

[Exposure level of neonicotinoid pesticides and their metabolites in pregnant women in the suburb of Shanghai].

In 2021, a total of 151 pregnant women were selected from the suburb of Shanghai. A questionnaire survey was conducted to obtain data about maternal age, gestational week, total annual household income, education level and passive smoking among pregnant women and one spot urine was collected. The concentrations of eight neonicotinoid pesticides and four metabolites in urine were measured by ultra-high performance liquid chromatography-tandem quadrupole time-of-flight mass spectrometry. The differences in detection frequencies and concentrations of neonicotinoid pesticides and their metabolites among pregnant women with different characteristics were compared, and the influencing factors of the detection of neonicotinoid pesticides in urine were analyzed. The results showed that at least one neonicotinoid pesticide was detected in 93.4% (141 samples) of urine samples. The detection frequencies of N-desmethyl-acetamiprid, clothianidin, thiamethoxam, and N-desmethyl-clothianidin were high, about 78.1% (118 samples), 75.5% (114 samples), 68.9% (104 samples), and 44.4% (67 samples), respectively. The median concentration of the sum of all neonicotinoid pesticides was 2.66 µg/g. N-desmethyl-acetamiprid had the highest detection concentration with a median concentration of 1.04 µg/g. A lower urinary detection frequency of imidacloprid and its metabolites was seen in pregnant women aged 30-44 years [OR (95%CI): 0.23 (0.07-0.77)]. A higher detection frequency of clothianidin and its metabolites was seen in pregnant women with per capita annual household income≥100 000 yuan [OR (95%CI): 6.15 (1.56-24.28)]. There was widespread exposure to neonicotinoid pesticides and their metabolites in pregnant women from the suburb of Shanghai, which might pose potential health risks to pregnant women, and maternal age and household income were potential influencing factors of the exposure to neonicotinoid pesticides.

[Clinical value of nomogram model in evaluating the prognosis of cholangiocarcinoma after interventional therapy].

Objective: To investigate the clinical value and efficacy of the nomogram model in evaluating the prognosis of cholangiocarcinoma after interventional therapy. Methods: The clinical data of 259 patients with cholangiocarcinoma who received interventional therapy at the First Affiliated Hospital of zhengzhou University from January 2014 to June 2021 were retrospectively analyzed, including 148 males and 111 females, aged from 26 to 91 (65±12) years. They were randomly divided into a training group (181 cases) and a validation group (78 cases) in a ratio of 7∶3. Cox regression analysis was performed in the training group, independent risk factors affecting the prognosis of patients were screened, and a nomogram for 6-month, 1-year, and 2-year survival was constructed. The performance of the nomogram was analyzed by calculating the area under the receiver operating characteristic curve (AUC) value, calibration curve, and decision curve, and the predictive efficacy of the model was evaluated in the validation group. Results: There was no significant difference in baseline data between the training group and the validation group, which was comparable. Regression analysis showed that T stage (T2: HR=0.147,95%CI: 0.077-0.281;T3: HR=0.207,95%CI: 0.122-0.351;T4: HR=0.864,95%CI: 0.537-1.393), tumor diameter (17-33 mm: HR=0.201,95%CI: 0.119-0.341;≥33 mm: HR=0.795,95%CI: 0.521-1.211) and differentiation degree(middle differentiation: HR=3.318,95%CI: 2.082-5.289;highly differentiation: HR=1.842,95%CI: 1.184-2.867) were risk factors affecting the prognosis of interventional therapy for cholangiocarcinoma. The AUC values of the survival curve prediction models were generally consistent between the training and validation groups, and the AUC values of the training group at 6 months, 1 year, and 2 years were 0.925 (95%CI: 0.888-0.963), 0.921 (95%CI: 0.877-0.964) and 0.974 (95%CI: 0.957-0.993), respectively. In the validation group, the 6-month, 1-year, and 2-year AUC values were 0.951 (95%CI: 0.911-0.991), 0.917 (95%CI: 0.857-0.977) and 0.848 (95%CI: 0.737-0.959), respectively, and the AUC values were all greater than 0.8, suggesting that the nomogram had better discrimination ability. The calibration curves of the prediction models of the two groups were basically consistent, and the shape of the calibration curves at 6 months and 1 year fitted the ideal curve, while the fitting degree of the calibration curves at 2 years was relatively poor. The decision curve showed the high clinical utility of this nomogram in predicting the 6-month, 1-year survival of patients with cholangiocarcinoma. Conclusions: T stage, tumor diameter, and differentiation are independent risk factors affecting the prognosis of patients with interventional cholangiocarcinoma, and the nomogram model proposed in this study has good distinguishing ability and exact clinical value for prognosis evaluation.

[Analysis on the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors].

Objective: To evaluate the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors. Methods: A COVID-19 outbreak caused by the Delta variant occurred in Nanjing in July 2021. A total of 235 cases with current addresses in Nanjing were reported from 171 households. The subjects in this study were selected from household close contact(s) of infected cases. The information on household index cases and their contacts were collected, and the household secondary attack rate (HSAR) and the risk factors were analyzed by the multi-factor logistic regression model. Results: A total of 234 cases of household close contacts and 64 household secondary cases were reported from 103 households, and the HSAR was 27.4% (64/234, 95%CI:22.0% to 33.4%). The proportions of household size for 2 to 3, 4 to 5, and 6 to 9 were 64.1% (66), 26.2% (27) and 9.7% (10), respectively. A total of 35 cases of household cluster outbreaks were reported (35/103, 34.0%). The number of the first case in the household (FCH) was 103 and males accounted for 27.2% (28 cases), with the median age (Q1, Q3) of 49 (9, 56). The number of household close contacts was 234 and males accounted for 59.0% (138 cases), with the median age (Q1, Q3) of 42 (20, 55) and the median exposure period (Q1, Q3) of 3 (1, 3) days. The multi-factor logistic regression model showed that the higher HSAR was observed in the FCH with the features of airport staff (OR=2.913, 95%CI:1.469-5.774), detection from home quarantine screening (OR=6.795, 95%CI:1.761-26.219) and detection from mass screening (OR=4.239, 95%CI:1.098-16.368). Meanwhile, higher HSAR was observed in cases with longer household exposure (OR=1.221, 95%CI:1.040-1.432), non-vaccination (OR=2.963, 95%CI:1.288-6.813) and incomplete vaccinations (OR=2.842, 95%CI:0.925-8.731). Conclusion: The generation interval of the Delta variant is shortened, and the ability of transmission within the household is enhanced. In the outbreak in Nanjing, the associated factors of HSAR are occupation, detection route, vaccination and exposure period.

[Clinical application of laparoscopic sentinel lymph node mapping in early staged cervical cancer].

Objective: To investigate the application of sentinel lymph node biopsy (SLNB) in early-staged cervical cancer by laparoscopy. Methods: It was a prospective, single-arm, single-center clinical study. Seventy-eight cases of cervical cancer patients were collected from July 2015 to December 2018 at the Fourth Hospital of Hebei Medical University. All the patients were injected with tracer into the disease-free block of cervical tissue after anesthesia by the same surgeon who learned sentinel lymph node (SLN) mapping technique in Memorial Sloan-Kettering Cancer Center, and underwent SLN mapping followed by complete pelvic lymphadenectomy. Moreover, all the dissected lymph nodes were stained with hematoxylin eosin staining (HE) pathological examination. Besides, the negative SLN on hematoxylin-eosin staining were detected by immunohistochemistry cytokeratin staining micro-metastasis. To analyze the distribution, detection rate, false negative rate the sensitivity and negative predictive value of the SLN in early-staged cervical cancer by laparoscopy, and explore the value of SLN mapping in predicting the lymph nodes metastasis in early-staged cervical cancer. Results: The overall detection rate of SLN in cervical cancer was 99% (77/78), bilateral detection rate was 87% (68/78). The average of 12.4 lymph node (LN) and 3.6 SLN were dissected for each patients each side. SLN of cervical cancer were mainly distributed in the obturator space (61.5%, 343/558), followed by external iliac (23.5%, 131/558), common iliac (7.3%, 41/558), para-uterine (3.8%, 21/558), internal iliac (2.2%, 12/558), para abdominal aorta (1.1%, 6/558), and anterior sacral lymphatic drainage area (0.7%, 4/558). Fourteen cases of LN metastasis were found among all 78 cases. There were a total of 38 positive LN, including 26 SLN metastasis and 12 none sentinel LN metastasis. Through immunohistochemical staining and pathological ultra-staging, 1 SLN was found to be isolated tumor cells (ITC), and 5 SLNs were found to be micro-metastases (MIC), accounting for 23% (6/26) of positive SLN. SLN mapping with pathological ultra-staging improved the prediction of LN metastasis in cervical cancer (2/14). Metastatic SLN mainly distributed in the obturator space (65%, 17/26), peri-uterine region (12%, 3/26), common iliac region (15%, 4/26), and external iliac region (8%, 2/26). The consistency of the diagnosis of lymph node metastasis by SLN biopsy and postoperative retroperitoneal lymph node metastasis showed that the Kappa value was 1.000 (P<0.001), indicated that the metastasis status of SLN and retroperitoneal lymph node were completely consistent. The sensitivity, specificity, accuracy, false-negative rate, and negative predictive value of SLN biopsy in the diagnosis of lymph node metastasis were 100%, 100%, 100%, 0, and 100%, respectively. Conclusions: SLN in early-staged cervical cancer patients were mainly distributed in the obturator and external iliac space, pathalogical ultra-staging of SLN could improve the prediction of LN metastasis. Intraoperative SLN mapping is safe, feasible and could predict the state of retroperitoneal LN metastasis in early-staged cervical cancer. SLNB may replace systemic pelvic lymphadenectomy.

[Analysis and forecast of burden of pancreatic cancer along with attributable risk factors in Asia countries between 1990 and 2019].

Objective: To analyze the disease burden of pancreatic cancer in major Asian countries and forecast the burden of that in China, which helps to provide reference for the prevention and control of pancreatic cancer. Methods: Data on disease burden of pancreatic cancer among global and major Asian countries from on the Global Burden of Disease (GBD) 2019 were collected to describe burden distribution through the absolute numbers or standardized rates of incidence, death and disability adjusted life years (DALY) by year, sex and socio-demographic index. Estimated annual percentage changes (EAPC) was used to assess the trend of standardized rate. The proportion of deaths attributable to risk factors for pancreatic cancer in 2019 was used to compare by age, sex and region. ARIMA model was performed with R language to predict change of age-standardized incidence and death rates of pancreatic cancer from 2020 to 2029. Results: From 1990 to 2019, the standardized incidence rates of pancreatic cancer in China increased from 3.17/100 000 to 5.78/100 000, and the standardized death rate increased from 3.34/100 000 to 5.99/100 000. The increases exceeded other high-income Asia countries. In the past three decades, the standardized incidence, death and DALY rates of pancreatic cancer in global have increased year by year. Among the major countries in Asia, China has the highest growth rate of disease burden (EAPC of standardized incidence rates=2.32%, 95% CI: 2.10%-2.48% and EAPC of standardized death rate=2.25%, 95% CI: 2.03%-2.42%). In addition, incidence and death rates of pancreatic cancer in China are expected to continue on the rise between 2000 and 2029 by ARIMA model. Incidence rate is expected to increase 15.92% and death rate is expected to increase 15.86%. Conclusions: The standardized incidence and death rates of pancreatic cancer in China increase year by year with an increasing trend for the burden of disease. The disease burden of pancreatic cancer is expected to rise due to the increase and aging of the population. Preventive measures should be adopted to decrease the burden of the pancreatic cancer.

[Temporal trend of antibiotic use among primary school children in Shanghai, 2017-2020].

To investigate the temporal trend of antibiotic use among children in Shanghai from 2017 to 2020. The stratified cluster sampling method was used to establish a dynamic cohort of healthy children based on primary schools in Changning District, Shanghai. In the cohort, there were 282 children from 2017, 287 children from 2018, 294 from 2019 and 301 from 2020. A total of 700 children aged 7-11 years were included in the study. The basic information and antibiotic use of children were investigated by questionnaire every year, and their height and weight were measured at the same time. Chi-square test was used to analyze the difference of antibiotic use rate in each year and generalized estimation equation was used to analyze the temporal trend of antibiotic use. The results showed that the use rates of all antibiotics, cephalosporins, azithromycin and other antibiotics (including penicillin, lincomycin, quinolones, etc.) of children between 2017 and 2020 were 15.6%, 10.5%, 2.7%, and 2.4%, respectively. In 2017, 2018, 2019, and 2020, there were significant differences for the use rates of total antibiotics and other antibiotics in children (P=0.033, P=0.040), and there were no significant differences for the use rates of cephalosporins and azithromycin (P=0.274, P=0.455). After adjusting for children's basic characteristics, the generalized estimation equation showed that the annual use rate of all antibiotics, cephalosporins, and other antibiotics decreased over time.

[Aesthetic reconstruction of the scar contracture deformity in chin and neck with expanded flaps based on the "MRIS" principle].

Objective: The surgical reconstruction strategy for scar contracture deformity in chin and neck was explored, aiming to obtain better aesthetic outcome. Methods: A retrospective observational study was conducted. From December 2017 to April 2021, 34 patients with scar contracture deformity in chin and neck after burns were hospitalized in the Department of Plastic Surgery of the First Affiliated Hospital of Army Medical University (the Third Military Medical University), aged 12-54 years, including 13 males and 21 females, 4 cases with chin affected only, 7 cases with neck affected only, and 23 cases with both chin and neck affected. The scar areas were 48-252 cm2. All the patients were treated by operation with expanded flaps, following the "MRIS" principle of matching of the color and thickness of the repair flaps (match), reconstructing of the aesthetic features of subunits (reconstruction), design of incision according to the plastic principle (incision), and prevention of the surgical incision scar (scar). The rectangular or kidney shaped skin and soft tissue expander (hereinafter referred to as the expander) with rated capacity of 80-400 mL was embedded in the first stage, which was routinely expanded to 3-5 times of the rated capacity of the expander. In the second stage, scar resection and expanded flap excision were performed to repair the secondary wound, and the flap donor site was sutured directly. The expansion ratio of the expander (with average value being calculated), the type of flaps used, the reconstruction of local aesthetic morphology, the appearance of postoperative incision, the survival of flap, and the situation of donor and recipient sites observed during follow-up were recorded. Results: Among the 34 patients, the average expansion ratio of the implanted expander was 3.82 times of the rated capacity of the expander. Three cases were repaired by the expanded local pedicled flap only, 19 cases by the expanded shoulder and/or chest perforator pedicled flap only, 10 cases by the expanded local pedicled flap combined with the expanded shoulder and/or chest perforator pedicled flap, and 2 cases by the expanded local pedicled flap combined with the expanded free flap of the second intercostal perforator of internal thoracic artery. After scar resection, the shapes of lower lip and chin-lip groove were reconstructed in 10 cases, chin process reconstruction and chin lengthening were performed in 16 cases, and the cervico-mental angle and mandibular margin contour were reconstructed in 28 cases. The surgical incision was concealed, most of which were located at the natural junction or turning point of the chin and neck subunits. The vertical incision of neck was Z-shaped or fishtail-shaped. All the expanded flaps in 34 patients survived after operation, of which 8 patients had minor necrosis at the edge or tip of the expanded flaps 1-3 days after operation and healed after dressing change. During the follow-up of 3-18 months, little difference in color and thickness between the expanded flap and the skin of chin and neck was observed, and the aesthetic shape of chin and neck was significantly improved, with mild scar hyperplasia of surgical incision. Conclusions: Reconstruction of scar contracture deformity in chin and neck by using expanded flaps based on the "MRIS" principle is beneficial to improve the quality of surgery and achieve better aesthetic outcome.

[Progress on clinical trials of common gastrointestinal cancer drugs in China from 2012 to 2021].

Objective: Systematically summarize the research progress of clinical trials of gastric cancer oncology drugs and the overview of marketed drugs in China from 2012 to 2021, providing data and decision-making evidence for relevant departments. Methods: Based on the registration database of the drug clinical trial registration and information disclosure platform of Food and Drug Administration of China and the data query system of domestic and imported drugs, the information on gastric cancer drug clinical trials, investigational drugs and marketed drugs from January 1, 2012 to December 31, 2021 was analyzed, and the differences between Chinese and foreign enterprises in terms of trial scope, trial phase, treatment lines and drug type, effect and mechanism studies were compared. Results: A total of 114 drug clinical trials related to gastric tumor were registered in China from 2012 to 2021, accounting for 3.7% (114/3 041) of all anticancer drug clinical trials in the same period, the registration number showed a significant growth rate after 2016 and reached its peak with 32 trials in 2020. Among them, 85 (74.6%, 85/114) trials were initiated by Chinese pharmaceutical enterprise. Compared with foreign pharmaceutical enterprise, Chinese pharmaceutical enterprise had higher rates of phase I trials (35.3% vs 6.9%, P=0.001), but the rate of international multicenter trials (11.9% vs 67.9%, P<0.001) was relatively low. There were 76 different drugs involved in relevant clinical trials, of which 65 (85.5%) were targeted drugs. For targeted drugs, HER2 is the most common one (14 types), followed by PD-1 and multi-target VEGER. In the past ten years, 3 of 4 marketed drugs for gastric cancer treatment were domestic and included in the national medical insurance directory. Conclusions: From 2012 to 2021, China has made some progress in drug research and development for gastric carcinoma. However, compared with the serious disease burden, it is still insufficient. Targeted strengthening of research and development of investment in many aspects of gastric cancer drugs, such as new target discovery, matured target excavating, combination drug development and early line therapy promotion, is the key work in the future, especially for domestic companies.

Mechanical performance of graphenex/poly(ether ketone ketone) composite sheets by hot pressing.

Polymer composites are gradually replacing traditional metal materials in the fields of aviation, aerospace, automotive and medicine due to their corrosion resistance, light weight and high strength. Moulding technology and organization morphology of polymer composite are key elements affecting the quality of products and their application, so a vacuum hot pressing process for graphenex/poly(ether ketone ketone) (PEKK) (x = 0%, 2%, 3%, 4%, 5%, 6%) composite powders is explored with particularly designed moulding parameters to achieve high conductive properties and good mechanical properties in graphene/PEKK composite sheet with thickness of 1.25 mm and diameter of 80 mm. The vacuum environment ensures that the graphene is not oxidized by air during hot pressing molding, which is essential for achieving conductive property in the graphene/PEKK composite; The hot pressing temperature of each graphene/PEKK composite powder is higher than glass transition temperature but lower than melting temperature, which ensures the graphene/PEKK composite powders is fully compacted and then graphene is fully lapped in the composite sheet. In addition, the graphene/PEKK composite sheet shows conductive property when the graphene content increases to 3wt%, and then the conductivity of the composites increases and then decreases with a peak value at 5wt% with increasing graphene content. By comparing the mechanical properties and microstructure morphology of the graphene/PEKK composite sheets, it was obtained that graphene content has an obvious effect on the mechanical properties of the composites, e.g., the mechanical properties will be increased as the graphene content increasing when graphene content is more than 3%. The graphene distribution law of the composite material with different graphene contents is analysed using a scanning electron microscope (SEM).

Beneficial effect of melatonin administration on the function of frozen-thawed rat testicular grafts.

BACKGROUND: Spermatogonia in testis is sensitive to the cytotoxicity of chemotherapy agents. Cryopreservation of testicular tissue may offer fertility restoration in young male cancer survivors. OBJECTIVE: To investigate the effect of melatonin on the survival of testicular grafts following cryopreservation and transplantation. MATERIALS AND METHODS: Wister rats were randomly allocated into three groups: control group; saline group (cryopreservation + autograft + saline); and melatonin group (cryopreservation + autograft + melatonin). Malondialdehyde (MDA) content, glutathione peroxidase (GPx) activity and superoxide dismutase (SOD) activity were assessed on day 7 after autograft transplantation. At day 30, graft recovery, spermatogonia per round tubule, and serum testosterone concentration in grafts were measured. RESULTS: Melatonin significantly diminished MDA content, enhanced GPx and SOD activities. Furthermore, the recovery rate, number of spermatogonia per round tubule, and serum testosterone concentration in melatonin group was markedly higher than the saline group. CONCLUSION: Melatonin administration at 20 mg/kg is effective in improving the function of frozen and thawed rat testicular graft. The protective role of melatonin can be attributed partly to the enhanced ROS scavenging and antioxidant enzyme activities. doi.org/10.54680/fr22310110612.

Damage of Granusola and Stroma Cells Exposed to Mouse Ovarian Tissue Cryopreservation: Potential Mechanism of Ovarian Injury.

BACKGROUND: Several obstacles must be overcome before ovarian tissue cryopreservation can be used as a standard procedure. OBJECTIVE: To carry out a morphologic and functional study of the effect of cryopreservation on mouse follicles and stroma cells. MATERIALS AND METHODS: Female mice were divided into three groups (control, fresh graft and cryopreserved graft). Ultrastructural features of follicles and stroma cells were evaluated using transmission electron microscopy. After autologous transplantation, micro-vessel densities of grafts were examined. RESULTS: Vacuoles in granulosa cells and stromal cells are significantly greater than that of oocytes. The microvessel density of fresh grafts is significantly higher than that in frozen-thawed grafts. CONCLUSION: Granusola and stroma cells, rather than oocytes, are vulnerable to cryoinjury. Injuries to granulosa cells and stromal cells could be the critical part of ovarian damage caused by cryopreservation.

[Progress on clinical trials of cancer drugs in China, 2020].

Objective: To explore the latest progress of oncology drug clinical trials in China under COVID-19, as well as to provide decision-making evidence for related stakeholders. Research progress of oncology drug trials and approved cancer drugs in China in 2020 were systematically summarized and compared with 2019. Methods: Information Disclosure Platform for Drug Clinical Studies and China Food and Drug Administration Query System for Domestic and Imported Drug were searched for registered clinical trials and approved oncology drugs, respectively. The trial scope, stage, drug type, effect and mechanism of domestic and global pharmaceutical enterprises were compared between 2019 and 2020. Results: A total of 722 cancer drug trials registered in China in 2020, with an annual growth rate of 52.3%, accounting for 28.3% of all registered trials. Among them, 603 (83.5%) trials were initiated by domestic pharmaceutical enterprises, and 105 (14.5%) were international multicenter trials, phase I trials accounted for 44.5%. For all those trials, there were 458 cancer drug varieties, with an annual growth rate of 36.7%, and 361 (85.8%) were developed by domestic enterprises. Most of the investigational products were therapeutic innovative drugs (77.1%), major in tumor treatment (92.8%). In terms of mechanism, targeted drugs were the most popular, accounting for 76.6%, and programmed cell death-1 (PD-1) and epithelial growth factor receptor (EGFR) were the most common targets. In addition, there were 19 anticancer drugs from 17 companies approved in China in 2019, with 10 drugs from domestic companies. Lung cancer and breast cancer are the most common indications for both registered trials and marketed drugs. No statistically significant differences were found between 2020 and 2019 in terms of the distribution of trial sponsor, scope and stage, as well as the distribution of drug type, effect and mechanism (P>0.05). Conclusions: During the Covid-19 epidemic period, clinical trials of oncology drugs in China progress smoothly and maintain a high growth rate. Series of innovative products obtained by domestic enterprises in 2020 is the main driving force of development of oncology drug clinical trials in China.

Linc-ROR promotes mesenchymal stem cells chondrogenesis and cartilage formation via regulating SOX9 expression.

OBJECTIVE: The present study is to characterize the role of long intergenic non-coding RNA, regulator of reprogramming (linc-ROR) in bone marrow mesenchymal stem cell (BMSCs) chondrogenesis, cartilage formation and OA development. METHODS: Linc-ROR expression pattern in articular cartilage tissue sample from OA patients were studied by real-time PCR. Linc-ROR lentivirus mediated BMSCs were constructed. In vitro micromass cultured BMSCs chondrogenesis or in vivo MeHA hydrogel encapsulated BMSCs cartilage formation activity were studied. Linc-ROR associating miRNAs which repressed SOX9 expression were characterized by luciferase assay, real-time PCR and Western blot. Linc-ROR was co-transfected with miRNAs into BMSCs to study its rescue effect on SOX9 expression and chondrogenesis activity. RESULTS: Linc-ROR was down-regulated in articular cartilage tissue from OA patients and was positively correlated with the expression level of SOX9 (R2 = 0.43). Linc-ROR expression was upregulated during BMSCs chondrogenesis. Linc-ROR ectopic expression significantly promoted in vitro BMSCs chondrogenesis and in vivo cartilage formation activities as revealed by safranin O, alcian blue and COL II staining. The mRNA expression level of chondrogenesis markers including COL II, SOX9 and ACAN were increased, and the hypertrophy markers MMP13 and COL X were decreased upon linc-ROR overexpression in BMSCs. Linc-ROR functioned as a miRNA sponge for miR-138 and miR-145. Both miR-138 and miR-145 suppressed BMSCs chondrogenesis activity and SOX9 expression, while co-expression of linc-ROR displayed a rescuing effect. CONCLUSIONS: Taken together, linc-ROR modulated BMSCs chondrogenesis differentiation and cartilage formation by acting as a competing endogenous RNA for miR-138 and miR-145 and activating SOX9 expression. Linc-ROR could be considered as a new diagnostic and therapeutic target for OA treatment.

[Analysis of gadolinium magnetic resonance in inner ear by tympanic membrane puncture in 1 126 cases].

Objective: To investigate the success rate, safety and repeatability of gadolinium (Gd)-enhanced inner ear magnetic resonance (MR) by tympanic membrane puncture. Methods: The imaging and clinical data of 1 126 cases with Gd-enhanced inner ear MR by tympanic membrane puncture from February 2010 to June 2020 were retrospectively analyzed. All cases were reexamined in the outpatient clinic after MR gadolinium contrast to check the tympanic membrane and external auditory canal. The success rate was identified by whether there was gadolinium contrast in the labyrinth. Meanwhile, the pure tone hearing threshold data of asymptomatic ears before and after gadolinium contrast was collected and compared. The consistency in the scores of the asymptomatic ears in patients who underwent twice Gd-enhanced MR was analyzed, in which the scores of vestibular, cochlea, and semicircular canals were acquired respectively. Results: Among 1 126 patients [including 506 males and 620 females, aged (54±17) years old], 45 were reviewed once, while 4 patients were reviewed twice. There were 958 cases who were examined on both sides, and 168 cases were checked only on one side. There were 166 cases of Meniere's disease (14.7%), 219 cases of sudden sensorineural hearing loss (19.5%) and 741 cases of being remained to be investigated (65.8%), respectively. A total of 2 084 ears underwent first gadolinium angiography, of which 63 ears had no contrast agent in the labyrinth, with a success rate of 97.0% (2 021/2 084). Only 1 case had tympanic membrane perforation while the rest had no complications. The hearing threshold before and after otography in 57 asymptomatic ears had no differences at any frequency (all P>0.05). Moreover, the consistency in the scores of two radiography within the 21 asymptomatic ears in vestibular and cochlea was good [both intraclass correlation coefficient (ICC) values>0.75]. Conclusion: The success rate and safety of Gd-enhanced inner ear MR is high by tympanic membrane puncture, and the results can be repeated well.