Exosomes derived from stem cells from the apical papilla alleviate inflammation in rat pulpitis by upregulating regulatory T cells

AIM

To evaluate the effects of exosomes derived from stem cells from the apical papilla (SCAP-Exos) in rats with experimentally induced pulpitis and the effects of SCAP-Exos on the conversion of regulatory T cells (Tregs) and methylation status of the Foxp3 locus in Tregs in vitro.

METHODOLOGY

SCAP-Exos were isolated and identified using transmission electron microscopy, western blotting, and nanoparticle tracking analysis. Lipopolysaccharide was used to experimentally induced pulpitis in rats, and the effects of SCAP-Exos on the rats with pulpitis were detected using haematoxylin-eosin staining and immunofluorescence staining. CD4+CD25- T cells were treated with different doses of SCAP-Exos, and flow cytometric analysis was used to assess the effects of SCAP-Exos on Treg proliferation and conversion. An enzyme-linked immunosorbent assay (ELISA) was used to evaluate the expression of interleukin 10 (IL-10). MethylTarget^® technology was used to measure the methylation level of the Foxp3 locus in T cells. The expression levels of ten-eleven-translocation (Tet) 1, Tet2, and Tet3 in T cells were detected by real-time PCR and western blotting.

RESULTS

SCAP-Exos had an elliptical vesicle-like structure with a diameter of approximately 143.7 nm and expressed the exosomal markers Alix and CD9. SCAP-Exo administration increased Treg accumulation in the inflamed dental pulp and alleviated inflammation in the dental pulp in vivo. SCAP-Exos promoted Treg conversion in vitro. Mechanistically, SCAP-Exos promoted Tet2-mediated Foxp3 demethylation to maintain the stable expression of Foxp3.

CONCLUSIONS

SCAP-Exos promoted Treg conversion and effectively alleviated inflammation in the dental pulp of rats. This study shows that SCAP-Exos can regulate the local immune microenvironment to favour tissue regeneration, thus providing a potential novel strategy utilising SCAP-Exos as a cell-free approach to treat early inflammation of dental pulp in immature permanent teeth in the clinic.

[The imaging characteristics and prognosis of patients with cochlear implants whose cochlear nerves are not shown on MRI]

Objective: To analyze the temporal bone CT and inner ear magnetic resonance imaging characteristics of cochlear implant patients with no cochlear nerve display in the inner auditory canal under MRI. To retrospectively analyze the long-term hearing and speech rehabilitation effects of such patients after cochlear implant. And to analyze the correlation between the results of imaging examinations and the postoperative effects of cochlear implant patients with this type of cochlear nerve deficiency. Methods: A total of 88 children with cochlear nerve deficiency, who underwent cochlear implantation in Shandong Provincial ENT Hospital from May 2014 to October 2018, were enrolled. Patients with cochlear malformations were excluded,only the patients with cochlear nerve deficiency whose cochlear structure was normal and no cochlear nerve displayed in inner auditory canal under MRI were enrolled. There were 64 patients, including 4 bilaterally implanted, 68 ears in total, with an average age of (2.8±1.7) years (range 1-6 years) at the time of implantation. The implanted product was Cochlear, including 24RECA and 512 models. All patients underwent inner ear magnetic resonance imaging and temporal bone CT scan before operation. Auditory speech function assessments were performed at 12 months, 24 months, and 36 months after surgery, including categories of auditory performance (CAP), speech intelligibility rating (SIR) and hearing aid threshold test. The imaging evaluation content included the width of the cochlear nerve canal of temporal bone CT, the width of the internal auditory canal, the width of the auditory nerve at the cerebellopontine angle of the inner ear MRI, and the ratio of the facial nerve to the width of the auditory nerve at the cerebellopontine angle. The correlations between the results of postoperative hearing aid hearing threshold, CAP, SIR and imaging results were analyzed. Results: Among the 64 cases of cochlear nerve not shown under MRI, 56 ears with CT data showed that the width of the cochlear nerve canal in temporal bone CT was (0.72±0.30) mm (mean±standard deviation, the same below), and the width of the internal auditory canal was (4.07±1.10) mm; 66 ears with MRI data showed that the diameter of the auditory nerve at the cerebellopontine angle of the inner ear MRI was (1.58±0.27) mm, the diameter of the facial nerve was (1.57±0.27) mm, and the ratio of the diameter of the facial nerve to the auditory nerve was (1.02±0.23). The average hearing thresholds at 12, 24, and 36 months after surgery were (46.8±2.5) dB HL, (40.7±0.8) dB HL, and (36.8±1.5) dB HL, respectively. The preoperative and postoperative CAP scores at 12, 24 and 36 months were (1.0±1.0), (3.8±1.4), (4.5±1.4) and (5.1±0.7) points, respectively. The preoperative and postoperative SIR scores at 12, 24, and 36 months were (1.1±0.3), (1.9±0.9), (2.5±0.9), and (2.9±0.6) points, respectively. The hearing threshold at 24 months after surgery was negatively correlated with the width of the internal auditory canal of temporal bone CT (r=-0.349, P=0.037), and the hearing threshold at 36 months after surgery was positively correlated with the ratio of the diameter of the facial nerve to the auditory nerve at the cerebellopontine angle of the inner ear MRI (r=0.740, P=0.001). Conclusions: Children with cochlear implants whose cochlear nerves are not shown on MRI can benefit from cochlear implantation, and their speech and auditory functions can improve significantly after surgery. The width of the internal auditory canal in the temporal bone CT and the ratio of the diameter of the facial nerve to the auditory nerve at the cerebellopontine angle of the inner ear MRI may be related to the long-term hearing threshold after surgery.

[Effect of splenectomy on the risk of hepatocellular carcinoma development among patients with liver cirrhosis and portal hypertension: a multi-institutional cohort study]

Objective: To identify whether splenectomy for treatment of hypersplenism has any impact on development of hepatocellular carcinoma(HCC) among patients with liver cirrhosis and hepatitis. Methods: Patients who underwent splenectomy for hypersplenism secondary to liver cirrhosis and portal hypertension between January 2008 and December 2012 were included from seven hospitals in China, whereas patients receiving medication treatments for liver cirrhosis and portal hypertension (non-splenectomy) at the same time period among the seven hospitals were included as control groups. In the splenectomy group, all the patients received open or laparoscopic splenectomy with or without pericardial devascularization. In contrast, patients in the control group were treated conservatively for liver cirrhosis and portal hypertension with medicines (non-splenectomy) with no invasive treatments, such as transjugular intrahepatic portosystemic shunt, splenectomy or liver transplantation before HCC development. All the patients were routinely screened for HCC development with abdominal ultrasound, liver function and alpha-fetoprotein every 3 to 6 months. To minimize the selection bias, propensity score matching (PSM) was used to match the baseline data of patients among splenectomy versus non-splenectomy groups. The Kaplan-Meier method was used to calculate the overall survival and cumulative incidence of HCC development, and the Log-rank test was used to compare the survival or disease rates between the two groups. Univariate and Cox proportional hazard regression models were used to analyze the potential risk factors associated with development of HCC. Results: A total of 871 patients with liver cirrhosis and hypertension were included synchronously from 7 tertiary hospitals. Among them, 407 patients had a history of splenectomy for hypersplenism (splenectomy group), whereas 464 patients who received medical treatment but not splenectomy (non-splenectomy group). After PSM,233 pairs of patients were matched in adjusted cohorts. The cumulative incidence of HCC diagnosis at 1,3,5 and 7 years were 1%,6%,7% and 15% in the splenectomy group, which was significantly lower than 1%,6%,15% and 23% in the non-splenectomy group (HR=0.53,95%CI:0.31 to 0.91,P=0.028). On multivariable analysis, splenectomy was independently associated with decreased risk of HCC development (HR=0.55,95%CI:0.32 to 0.95,P=0.031). The cumulative survival rates of all the patients at 1,3,5,and 7 years were 100%,97%,91%,86% in the splenectomy group,which was similar with that of 100%,97%,92%,84% in the non-splenectomy group (P=0.899). In total,49 patients (12.0%) among splenectomy group and 75 patients (16.2%) in non-splenectomy group developed HCC during the study period, respectively. Compared to patients in non-splenectomy group, patients who developed HCC after splenectomy were unlikely to receive curative resection for HCC (12.2% vs. 33.3%,χ²=7.029, P=0.008). Conclusion: Splenectomy for treatment of hypersplenism may decrease the risk of HCC development among patients with liver cirrhosis and portal hypertension.

[Effects of dezocine on cardiac myocytes injury induced by hypoxia and reoxygenation in rats and its mechanism]

Objective: To investigate the mechanisms of dezocine on regulating H9C2 oxidative stress and apoptosis of rat cardiac myocytes induced by hypoxia-reoxygenation(H/R) by regulating the expressions of microRNA-7a- 5p(miR-7a-5p)/ubiquitin E3 ligase tripartite motif 10(TRIM10). Methods: H9C2 cells were divided into control group (cultured normally), H/R group (treated with hypoxia for 3 h and then reoxygenation for 4 h), different doses of dezocine intervention group (H9c2 cells were pretreated with dezocine at the concentrations of 10^-7, 10^-6 and 10^-5 mmol/L for 24 h, and then treated with H/R), H/R+miR-7a-5p group (H9C2 cells were transfected with miR-7a-5p mimics and then treated with H/R), H/R+miR-NC group (H9C2 cells were transfected with miR-NC and then treated with H/R), H/R+Dezocine+anti-miR-7a-5p group (H9c2 cells transfected with anti-miR-7a-5p were pretreated with 10^-5 mmol/L dezocine for 24 h, and then treated with H/R), H/R+dezocine+ anti-miR-NC Group (H9c2 cells transfected with anti-miR-NC were pretreated with 10^-5 mmol/L dezocine for 24 h, and then treated with H/R). Each group of cells was set with 3 replicate wells, and the experiment was repeated 3 times. The content of malondialdehyde(MDA) and activity of superoxide dismutase(SOD) and glutathione peroxidas(GSH-Px) were detected by the enzyme-linked immunosorbent assay. The cells apoptosis was detected by flow cytometry. The protein expressions of B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax) and TRIM10 were detected by Western blot, and the expressions of miR-7a-5p and TRIM10 mRNA were detected by real-time quantitative PCR(RT-qPCR). The double luciferase reporter gene experiment was used to verify the regulatory relationship between miR-7a-5p and TRIM10. Results: Compared with the control group, the MDA content, apoptosis rate, the expression of Bax protein, and the expression of TRIM10 mRNA and protein in the H/R group were all increased (P＜0.05), while the activities of SOD and GSH-Px, and the expressions of Bcl-2 protein and miR-7a-5p were all decreased (P＜0.05). Compared with the H/R group, the MDA content, apoptosis rate, the expression of Bax protein, and the expression of TRIM10 mRNA and protein in the different doses of dezocine intervention group were decreased (P＜0.05), while the activities of SOD and GSH-Px, and the expressions of Bcl-2 protein and miR-7a-5p were all increased (P＜0.05), and there were significant differences in each index between the different doses of dezocine intervention groups (P＜ 0.05). Compared with the H/R+miR-NC group, the MDA content, apoptosis rate, the protein expressions of Bax and TRIM10 in the H/R+miR-7a-5p group were decreased (P＜0.05), while the activities of SOD and GSH-Px, and the expression of Bcl-2 protein were all increased (P＜0.05). Compared with the H/R+dezocine+anti- miR-NC group, the MDA content, apoptosis rate, the protein expressions of Bax and TRIM10 in the H/R+dezocine+anti-miR-7a-5p group were all increased (P＜0.05), while the activities of SOD and GSH-Px, and the expression of Bcl-2 protein were all decreased (P＜0.05). Conclusion: Dezocine can reduce oxidative stress and apoptosis of rat cardiomyocytes H9C2 induced by H/R, which may play a role in regulating the miR-7a-5p / TRIM10 axis.

[Prognostic factor analysis of patients with unresectablelung squamous cell carcinoma]

Objective: To investigate the prognostic factors associated with unresectable (stage Ⅲa-Ⅳ, according to the 7th edition of the AJCC cancer staging manual) lung squamous cell carcinoma. Methods: We retrospectively analyzed 350 patients with inoperable locally advanced, recurrent or metastatic lung squamous cell carcinoma who were admitted to the First Affiliated Hospital of Chinese Medical University from January 2005 to June 2018. The clinical pathological data, treatment and survival follow-up information of the patients were collected. Kaplan-Meier survival was used to compare the overall survival rate of different risk groups. Univariate analysis and multivariate Cox regression analysis were used to determine the independent prognostic factors. Results: A total of 350 patients were enrolled. The median overall survival (OS) of these patients was 16.7 months. Univariate analysis showed the stage, Eastern Cooperative Oncology Group(ECOG), first-line chemotherapy evaluation (RECIST version 1.1), radiation therapy, number of systemic chemotherapy lines, carcinoembryonic antigen (CEA), cancer antigen 125 (CA125), C reactive protein (CRP), lactate dehydrogenase (LDH), whether liver, brain, boneor metastasis were associated with the OS of patients with advanced lung squamous cell carcinoma (all P<0.05). Multivariate analysis showed that ECOG score (HR=1.855, 95% CI: 1.063-3.239, P=0.030), whether underwent lung resection (HR=0.476, 95%CI: 0.302-0.751, P=0.001), first-line chemotherapy evaluation [stable disease (SD): HR=0.293, 95%CI: 0.159-0.540, P<0.001; complete response (CR)+ partial response (PR): HR=0.223, 95%CI: 0.120-0.413, P<0.001], CRP (HR=1.715, 95% CI: 1.080-2.723, P=0.042), LDH (HR=1.116, 95%CI: 0.780-1.596, P=0.002) and CEA (HR=1.855, 95%CI: 1.361-2.528, P<0.001) before chemotherapy, liver metastasis (HR=2.453, 95%CI: 1.461-4.120, P=0.001) are independent prognostic factors for patients with unresectable lung squamous cell carcinoma. Conclusion: The ECOG score, surgical treatment history, first-line chemotherapy, LDH, CEA and CRP before chemotherapy, liver metastasis are independent prognostic factors for patients with advanced lung squamous cell carcinoma.

[Left ventricular guidewire pacing during transcatheter aortic valve replacement]

Objective: To investigate the safety and efficacy of left ventricular guidewire pacing during transcatheter aortic valve replacement (TAVR). Methods: This is a retrospective study. Thirteen patients, who underwent TAVR with left ventricular guidewire pacing from October 2019 to December 2019 in Fuwai Hospital, were included. Clinical data and operational procedure data of the patients were collected. Changes in blood pressure and electrocardiogram were observed during operations. Ascending aorta angiography was performed to evaluate the regurgitation of aortic valve after valve implantion. The incidence of major adverse cardiac events during hospitalization and at 3-months after discharge was recorded. Results: There were 7 male and 6 female patients in this cohort,and age was (73.8±8.3) years old. Among the 13 patients, 9 were tricuspid aortic valves, 3 were bicuspid aortic valves, and 1 was degenerated bioprosthetic surgical aortic valve. TAVR were successfully performed in all of the 13 cases using pacing through the left ventricular guidewire. During balloon dilation, the blood pressure decreased to below 60 mmHg (1 mmHg=0.133 kPa) after 180 beats/min pacing, and the valve release process was smooth and the position was stable. The results of aortography showed that there was no regurgitation in 7 cases, mild regurgitation in 5 cases and moderate regurgitation in 1 case. Three patients required temporary pacing during the procedure due to complete heart block, among whom 1 patient was implanted with permanent pacemaker during hospitalization, and the other 2 patients recovered within 24 hours after operation. In another case, there was no significant change of electrocardiogram during the operation, and complete heart block occurred 10 days after the operation, and treated with permanent pacemaker. The other 10 patients began to carry out bedside activities and rehabilitation training 24 hours after operation. There was no death, myocardial infarction, stroke and other major adverse cardiac events during hospitalization and at 3-month follow-up after discharge. Conclusion: Left ventricular guidewire pacing is a safe and effective strategy for TAVR.

[Predicting response to non-small cell lung cancer immunotherapy using pre-treatment contrast-enhanced CT texture-based classification]

Objective: To explore the value of pre-treatment contrast-enhanced computed tomography (CT)-based texture analysis in predicting response to non-small cell lung cancer (NSCLC) immunotherapy. Methods: From January to July 2018, a total of 51 lesions from 42 patients with advanced non-small cell lung cancer receiving immunotherapy at Shanghai Chest Hospital were selected in this retrospective study. Pre-treatment contrast-enhanced CT-based texture features were extracted by MaZda software. Ten optimal texture features were chosen based on three different methods: Fisher coefficient, mutual information measure (MI) and minimization of classification error probability combined average correlation coefficients(POE+ ACC), respectively. According to the efficacy of the first immunotherapy, 51 lesions were divided into non-progressive disease (non-PD, n=26) and progressive disease (PD, n=25). The differences were tested in each texture feature set between the two groups. The immunotherapy effects of target lesions were analyzed by principal component analysis(PCA), linear discriminant analysis (LDA) and nonlinear discriminant analysis (NDA). The sensitivity, specificity, accuracy, positive-predictive value (PPV) and negative-predictive value (NPV) were calculated. The area under the curve (AUC) was used to quantify the predictive accuracy of the three analysis models for each texture feature set and compare them with the actual classification results. Results: In all of three texture feature sets, the texture parameter differences of Perc.50%, Perc.90%, "S(5, 5)SumEntrp" and "S(4, 4)SumEntrp" were higher in PD group than those in non-PD group (all P<0.05). The classification result of texture feature set chosen by POE+ ACC and analyzed by NDA was identified as the best model (AUC=0.802, 95%CI: 0.674-0.930), and its sensitivity, specificity, accuracy, PPV and NPV were 72%, 88.5%, 80.4%, 85.7%, 76.7%, respectively. Conclusion: Pre-treatment contrast-enhanced CT-based texture characteristics of NSCLC may function as non-invasive biomarkers for the evaluation of response to immunotherapy.

Optimal reference genes for real-time quantitative PCR and the expression of sigma factors in Acidithiobacillus caldus under various conditions

AIMS

Acidithiobacillus caldus is an important sulphur-oxidizing bacterium that plays crucial roles in the bioleaching industry. This study aims to analyse the optimal reference gene for real-time quantitative PCR (RT-qPCR) under different conditions and investigate the transcription levels of the sigma factor genes in the stress response.

METHODS AND RESULTS

We selected six housekeeping genes and analysed them via RT-qPCR using two energy resources, under four stress conditions. Three statistical approaches BestKeeper, geNorm, and NormFinder were utilized to determine transcription stability of these reference genes. The gapdH gene was the best internal control gene using elemental sulphur as an energy resource and under heat stress, map was the best internal control gene under pH and osmotic stress, era was the best internal control gene for the K₂ S₄ O₆ energy resource, and rpoC was the best internal control gene under Cu²⁺ stress. Furthermore, the expressional levels of 11 sigma factors were analysed by RT-qPCR in the stress response.

CONCLUSIONS

Stable internal control genes for RT-qPCR analysis of A. caldus were determined, and the expression patterns of sigma factor genes of A. caldus were investigated.

SIGNIFICANCE AND IMPACT OF THE STUDY

The identification of the optimal reference gene and analysis of transcription levels of sigma factors in A. caldus can provide clues for reference gene selection and the study of sigma factor function.

[Clinical efficacy of two-staged Fowler-Stephens laparoscopic orchidopexy in the treatment of children with high cryptorchidism]

Objective: To Evaluate the clinic effect of two-staged laparoscopic Fowler-Stephens orchiopexy in the treatment of high cryptorchidism, and compare it with laparoscopic orchiopexy treatment without disconnecting spermatic vessels. Methods: A retrospective analysis was conducted on 20 cases of children with high cryptorchidism who were treated with two-staged Fowler-Stephens orchiopexy from January 2015 to April 2019 (F-S group). All the children in this group had unilateral cryptorchidism, age 6 to 18 months. The average age was 13.5 months. Seven cases were on the left side, and 13 cases were on the right side. There were 20 control children in the same age group who were treated with testicular fixation without disconnecting spermatic vessels, age 6 to 18 months. The average age was 12.5 months. Six cases were on the left side, and 14 cases were on the right side. Testicular ultrasonography and sex hormone examination were conducted before operation. F-S group met the indications for Fowler-Stephens surgical. In the first stage, the testicular vessels were doubly clipped at a site away from the testis in laparoscopic, and the second stage was scheduled about 6 months after the first stage. The children in the control group were treated with laparoscopic orchiopexy without disconnect spermatic vessels. The two groups were followed up to 6 months after the operation, and the testicular volume and sex hormone indexes of the two groups were measured. The testicular volume and sex hormones before and after the operation of the F-S group and the control group were respectively subjected to a self-control study, and a hormone comparison study was carried out between the two groups of children. Results: Both the F-S group and the control group successfully fixed the testes in the scrotum without tension during the operation. In both groups, 20 cases of testicular positions were reexamined 6 months after the operation without retraction. All the patients had a viable testis in scrotum after operation. Two of F-S group had an atrophic testis in the scrotum, and the others had a good vascularization detected on echo color doppler ultrasound. The average testicular volume of F-S group was (0.34±0.16) ml before operation and the postoperative one was (0.38±0.13) ml, P=0.089, P>0.05. In control group, the preoperative average testicular volume was (0.40±0.14) ml, and postoperative one was (0.40±0.15) ml, P=0.933, P>0.05. The testicular volume of two group had no significant difference. Sex hormone reexamination: Testosterone (T), estradiol (E2) and luteinizing hormone (LH) did not change after operation. Prolactin (PRL) in F-S group was 13.44 μg/L before operation and 12.3 μg/L after operation, PRL in control group was from 15.45 μg/L to 10.34 μg/L, P=0.732, the change of prolactin (PRL) has no significant difference. The median preoperative follicle stimulating hormone (FSH) in the F-S group was 1.18 U/L preoperatively and 1.61 U/L postoperatively; the median FSH of the control group was 1.21 U/L preoperatively and 1.1 U/L postoperatively. Compared between the two groups, the postoperative increase in the FS group was higher than that before the operation, P=0.032, P<0.05, the difference was statistically significant. The median of progesterone (PROG) in the F-S group was 0.25 nmol/L before operation and 0.17 nmol/L after operation; the median PROG of the control group was 0.56 nmol/L before operation and 0.24 nmol/L after operation. It was lower after the operation than before the operation, P=0.034, P<0.05, the difference was statistically significant. Conclusions: (1) Laparoscopic Fowler-stephens staging operation is an effective method for the treatment of patients with high cryptorchidism, and it is worthy of further promotion. (2) Disruption of spermatic cord vessels does have an impact on hormones changes. The choice of this surgical procedure should be carefully and fully evaluated.

[ Ⅲ ]

Objective: To compare the efficacy and safety of Changsulin^® with Lantus^® in treating patients with type 2 diabetes mellitus (T2DM). Methods: This was a phase Ⅲ, multicenter, randomized, open-label, parallel-group, active-controlled clinical trial. A total of 578 participants with T2DM inadequately controlled on oral hypoglycemic agents were randomized 3∶1 to Changsulin^® or Lantus^® treatment for 24 weeks. The efficacy measures included changes in glycosylated hemoglobin (HbA1c), fasting plasma glucose (FPG), 2h postprandial plasma glucose (2hPG), 8-point self-monitoring of blood glucose (SMBG) profiles from baseline, and proportions of subjects achieving targets of HbA1c and FPG. The safety outcomes included rates of hypoglycemia, adverse events (AEs) and anti-insulin glargine antibody. Results: After 24 weeks of treatment, mean HbAlc decreased 1.16% and 1.25%, FPG decreased 3.05 mmol/L and 2.90 mmol/L, 2hPG decreased 2.49 mmol/L and 2.38 mmol/L in Changsulin^® and in Lantus^®, respectively. No significant differences could be viewed in above parameters between the two groups (all P>0.05). There were also no significant differences between Changsulin^® and Lantus^® in 8-point SMBG profiles from baseline and proportions of subjects achieving the targets of HbA1c and FPG (all P>0.05). The rates of total hypoglycemia (38.00% and 39.01% for Changsulin^® and Lantus^®, respectively) and nocturnal hypoglycemia (17.25% and 16.31% for Changsulin^® and Lantus^®, respectively) were similar between the two groups (all P>0.05). Most of the hypoglycemia events were asymptomatic, and no severe hypoglycemia were found in both groups. No differences were observed in rates of AEs (61.77% vs.52.48%) and anti-insulin glargine antibody (after 24 weeks of treatment, 6.91% vs.3.65%) between the two groups (all P>0.05). Conclusions: Changsulin^® shows similar efficacy and safety profiles compared with Lantus^® and Changsulin^® treatment was well tolerated in patients with T2DM.

Improving probiotic spore yield using rice straw hydrolysate

Spore-forming Bacillus sp. has been extensively studied for their probiotic properties. In this study, an acid-treated rice straw hydrolysate was used as carbon source to produce the spores of Bacillus coagulans. The results showed that this hydrolysate significantly improved the spore yield compared with other carbon sources such as glucose. Three significant medium components including rice straw hydrolysate, MnSO₄ and yeast extract were screened by Plackett-Burman design. These significant variables were further optimized by response surface methodology (RSM). The optimal values of the medium components were rice straw hydolysate of 27% (v/v), MnSO₄ of 0·78 g l^-1 and yeast extract of 1·2 g l^-1 . The optimized medium and RSM model for spore production were validated in a 5 l bioreactor. Overall, this sporulation medium containing acid-treated rice straw hydrolysate has a potential to be used in the production of B. coagulans spores.

[A preliminary study on establishment of the Core Occupational Stress Scale (COSS) norms for manufacturing and medical workers in China]

Objective: To establish the Core Occupational Stress Scale (COSS) norm values for manufacturing and medical workers. Methods: A total of 10 316 manufacturing workers of 20 companies from 7 provincial capital cities and 5 031 medical workers of 19 hospitals from 4 provincial capital cities were investigated using a stratified sampling method. Questionnaire information including occupational stress was collected. Norms of mean, percentile and T scores were calculated for COSS total and sub-dimension scores by different demographic characteristics. Based on the normal distribution, cut points of x¯+0.5s, x¯+s, x¯+1.5s of COSS total scores were calculated to classify the degree of occupational stress. Results: The COSS total scores were (45.48±8.16) and (45.71±8.46). The 50th percentiles were both 46, and T score ranges were (15-92) and (16-91), respectively, for manufacturing and medical workers. When the total score was<50, 50-53, 54-57, and >57 for manufacturing worker, or<50, 50-54, 55-58, and >58 for medical workers, occupational stress would be classified into none, mild, moderate, and severe levels. Conclusion: Compatible with the national condition of China, as well as the principles of psychological measurement, these norm values for manufacturing and medical workers could provide theoretical support and practical guideline on occupational mental health promotion.

[Development of the Core Occupational Stress Scale for occupational populations in China]

Objective: To develop the Core Occupational Stress Scale (COSS) for key occupational populations, and to assess the reliability and validity of COSS in China. Methods: According to the literature review, in-depth interview and expert evaluation, the item pool of COSS was established. A total of 20 981 employees (3 703 employees from 2018 and 17 178 employees from 2019) of manufacturing, medical, and traffic polices, etc. from Beijing, Tianjin, Shanghai, Chongqing, Jiangsu, Shandong, Zhejiang, Hunan, Guangdong and Hubei were investigated using convenient sampling of those participating in general or occupational health examination of the day. Item differential test and exploratory factor analysis (EFA) were used to screen items from the item pool; confirmatory factor analysis (CFA) was used to test structure validity; criterion and convergent validity were tested by Pearson correlation. Cronbach's α coefficient was used to test the reliability of the scale. Results: The EFA suggested a four-factor structure for a 17-item version of COSS, which were social support, organization and reward, demand and effort, and control. It explained 62.06% of the total variance and factor loadings ranged from 0.447 to 0.918. The CFA confirmed the hypothesized four-factor model (GFI=0.904, CFI=0.912, RMSEA=0.079). The COSS scores were positively correlated with burnout, depressive symptoms, and effort-reward imbalance scores with r ranging from 0.357 to 0.567 (P<0.05). The total COSS and each dimension of Cronbach's α coefficients were 0.772-0.896. Conclusions: The COSS has good reliability and validity and can be used as an occupation stress assessment for occupational populations in China.

[Clinical study of anti-human T cell porcine immunoglobulin with recombinant human tumor necrosis factor-α receptor II: IgG Fc in the treatment of 35 cases of grade III/IV acute graft-versus-host disease after allo-HSCT]

Objective: To evaluate the efficacy and safety of anti-human T lymphocyte porcine immunoglobulin (P-ATG) with recombinant human tumor necrosis factor-α receptor Ⅱ:IgG Fc fusion protein (rhTNFR∶Fc, Etanercept) on grade Ⅲ/Ⅳ acute graft-versus-host disease (aGVHD) after allogenic hematopoietic stem cell transplantation (allo-HSCT) . Methods: Thirty-five patients with Grade Ⅲ/Ⅳ aGVHD who received P-ATG with etanercept therapy after allo-HSCT were retrospectively analyzed. P-ATGs (5 mg·kg(-1)·d(-1)) were administrated for 3 to 5 days, and then 5mg/kg was sequentially administrated, QOD to BIW. Etanercepts were administrated 25 mg, twice a week (12.5 mg, BIW for pediatric patients) . Results: Among the 35 patients with grade Ⅲ/Ⅳ aGVHD, 21 were males and 14 females, with a median age of 10 (3-54) years. A total of 19 cases of acute myeloid leukemia, 13 of acute lymphoblastic leukemia, 1 of severe aplastic anemia, 1 of myelodysplastic syndrome, and 1 of mixed phenotypic acute leukemia were noted. The overall response (OR) rate of P-ATG with etanercept was 85.7% (30/35) , with complete response (CR) and partial response (PR) rates of 34.3% (12/35) and 51.4% (18/35) , respectively, on day 28. The OR rate of grade Ⅲ aGVHD group was higher than of grade IV aGVHD group [100% (19/19) vs. 68.8% (11/16) , P=0.004]. On day 56, the OR rate became 77.2% (27/35) , with CR and PR rates of 62.9% (22/35) and 14.3% (5/35) , respectively. The OR rate of grade Ⅲ aGVHD group was also higher than of grade Ⅳ aGVHD group [89.5% (17/19) vs. 62.5% (10/16) , P=0.009]. Thirty-five patients had no adverse effects such as fever, chills, and rash during the P-ATG infusion, and no obvious liver and kidney function damage was observed after treatment. The main treatment-related complication was infection. The reactivation rates of CMV and EBV were 77.1% (27/35) and 22.9% (8/35) , respectively, and the bacterial infection rate was 48.6% (17/35) . With a median follow-up time of 13 (1-55) months after HSCT, the 1-year and 2-year OS rates were (68.1±8.0) % and (64.3±8.4) % , respectively. The 1-year OS rate of grade Ⅲ aGVHD group was superior to grade Ⅳ aGVHD group [ (84.2±8.4) % vs. (47.6±13.1) % , χ(2)=3.38, P=0.05]. Conclusion: This study demonstrated that P-ATG with etanercept was effective and safe in treating grade Ⅲ-Ⅳ aGVHD after allo-HSCT.

Personalized Three-Dimensional Printed Anterior Titanium Plate to Treat Double-Column Acetabular Fractures: A Retrospective Case-Control Study

Objective

To compare the clinical efficacy and safety of a personalized three‐dimensional (3D) printed dynamic anterior plate–screw system for the quadrilateral area (DAPSQ) titanium plate and a traditional DAPSQ reconstruction plate in the treatment of double‐column acetabular fractures.

Methods

This was a retrospective case‐control study. From May 2014 to January 2018, 43 patients with double‐column acetabular fractures underwent open reduction and internal fixation. Among these, 20 cases were fixed with a 3D printed DAPSQ plate (3D printed group) and 23 cases were fixed with a DAPSQ reconstruction plate (control group). The 3D printed group comprised 15 men and 5 women, with an average age of 50.1 ± 8.2 years. The control group comprised 16 men and 7 women, with an average age of 51.0 ± 8.6 years. The evaluation index included the surgical data (i.e. blood loss, operating time, duration of hospital stay, and intraoperative and postoperative complications), position and length of implants, reduction quality, hip function, and related complications. The reduction quality was evaluated using the Matta scoring standard and hip function was evaluated using the modified Merle d’Aubigné score.

Results

A total of 43 patients met the inclusion criteria. The mean postoperative follow up was 35.2 months in the 3D printed group and 36.9 months in the control group. There were no significant group differences in demographic data between the two groups. The position and length of the 3D printed implants were generally in accord with preoperative planning using a 3D pelvic model. Patients in the 3D printed group had significantly shorter operation time (223.2 vs 260.5 min, P < 0.05) and less intraoperative blood loss (930.4 vs 1426.1 mL, P < 0.05) compared to the control group. Anatomic, imperfect, and poor reduction was obtained in 13, 5, and 2 cases in the 3D printed group, respectively, and was obtained in 12, 8, and 3 cases in the control group. The modified Merle d’Aubigné scores were excellent in 11 cases, good in seven cases, and fair in two cases in the 3D printed group. They were excellent in 11 cases, good in eight cases, fair in three cases, and poor in one case in the control group. The reduction quality and hip function did not differ within the groups (P > 0.05). The general complication rate in the 3D printed group and the control group was 15% and 26.1%, respectively, but the difference between the two groups was not statistically significant.

Conclusion

Use of a personalized 3D printed DAPSQ plate has potential advantages in reducing the operation time and blood loss during the treatment of double‐column acetabular fractures.

[Experts consensus for the diagnosis, treatment, and prevention of Coronavirus disease 2019 in the elderly]

Coronavirus disease 2019 (COVID-19) can cause great damage to the elderly patients and lead to high mortality. The clinical presentations and auxiliary examinations of the elderly patients with COVID-19 are atypical, due to the physiological ageing deterioration and basal pathological state. The treatment strategy for the elderly patients has its own characteristics and treatment protocol should be considered accordingly. To improve the diagnosis, treatment, and prevention of COVID-19 in the elderly, the Expert Committee of Geriatric Respiratory and Critical Care Medicine, China Society of Geriatrics established the "Expert consensus for the diagnosis, treatment, and prevention of Coronavirus disease 2019 in the elderly" . We focused on the clinical characteristics and key points for better treatment and prevention of COVID-19 in the elderly. (1) For diagnosis, atypical clinical presentation of COVID-19 in the elderly should be emphasized, which may be complicated by underlying disease. (2) For treatment, strategy of multiple disciplinary team (mainly the respiratory and critical care medicine) should be adopted and multiple systemic functions should be considered. (3) For prevention, health care model about integrated management of acute and chronic diseases, in and out of hospital should be applied.

[Thoughts and practice on the treatment of severe and critical new coronavirus pneumonia]

Severe and critical coronavirus pneumonia 2019 (COVID-19) often occurs in elder patients with multiple comorbidities, and severe hypoxemia events constitute a key factor for the deterioration of some cases. The critical type of COVID-19 could progress into acute respiratory distress syndrome and multi-organ dysfunction, which are the major causes of death. Early non-invasive ventilation (NIV) treatment of possible pathophysiological abnormalities is helpful to improve prognosis. Close monitoring of oxygenation, reducing patients' oxygen consumption, active psychological intervention, and rapid handling of severe hypoxemia events are the key factors for successful NIV treatment. In addition, active adjuvant therapies such as correcting coagulation dysfunction, providing proper nutritional support, accurate volume control, and safe individualized blood glucose monitoring are of great significance.

Cell migration and osteo/odontogenesis stimulation of iRoot FS as a potential apical barrier material in apexification

AIM

To investigate the in vitro biological effects of a nanoparticle bioceramic material, iRoot Fast Set root repair material (iRoot FS), on the proliferation, migration and osteo/odontogenic differentiation of human stem cells from the apical papilla (hSCAP), and to further explore the mechanism involved in osteo/odontogenic induction of iRoot FS.

METHODOLOGY

hSCAP were isolated and characterized in vitro. iRoot FS conditioned medium were prepared and used to treat hSCAP, while using mineral trioxide aggregate (MTA) conditioned medium as the positive control and regular medium as the negative control. MTT assay and BrdU labelling assay were performed to determine cell proliferation. Wound healing assay and transwell assay were conducted to evaluate cell migration. The osteo/odontogenic differentiation of hSCAP was evaluated by qPCR, Western blot and Alizarin red S staining. Wnt inhibitor was used for downregulating the expression level of β-catenin of hSCAP.

RESULTS

The cell proliferation of hSACP in the iRoot FS group was not significantly different compared with the control groups. The cell migration of hSCAP in the iRoot FS group was significantly increased than the MTA and negative control groups (P < 0.01). The expression levels of osteo/odontogenic markers and mineralization nodule formation of hSCAP in the iRoot FS group were significantly elevated (P < 0.01). Furthermore, iRoot FS enhanced the osteo/odontogenic differentiation of hSCAP by activating Wnt/β-catenin signalling.

CONCLUSIONS

iRoot FS promoted the cell migration of hSCAP and enhanced their oseto/odontogenesis potential via the Wnt/β-catenin pathway without cytotoxicity. iRoot FS had satisfactory biological properties and has potential to be used as an apical barrier in apexification or as a coronal sealing material in regenerative endodontic treatment.

[Outcome of children with T cell acute lymphoblastic leukemia treated with Chinese Children Leukemia Group acute lymphoblastic leukemia (CCLG-ALL) 2008 protocol]

Objective: To evaluate the efficacy of the Chinese Children's Leukemia Group (CCLG) acute lymphoblastic leukemia (ALL) 2008 protocol (CCLG-ALL 2008) in the treatment of children's T-cell acute lymphoblastic leukemia (T-ALL). Methods: Clinical characteristics and outcomes of 84 newly diagnosed T-ALL children (63 males and 21 females) treated with CCLG-ALL 2008 protocol from April 2008 to April 2015 in the Department of Pediatric Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences were analyzed retrospectively. Kaplan-Meier analysis was used to evaluate the overall survival (OS) and event free survival (EFS), and COX regression was used to evaluate the influencing factors of OS and EFS. Results: (1) Baseline data: 84 children were included, 56 cases (67%) of children were younger than 10 years old. Patients whose white blood cell count≥50×10(9)/L ranked 70% (59/84). Karyotype: 58% (49/84) with normal karyotype, 10% (8/84) with abnormality of chromosome 11, 8%(7/84) with abnormality of chromosome 9, 2%(2/84) with abnormality in both chromosome 11 and chromosome 9, 8% (7/84) with other complex karyotypes. Fusion gene: 33%(28/84) were SIL-TAL1 positive. The patients were grouped by CCLG-ALL 2008 risk score, 40% (34/84) were in the intermediate risk group and 60% (50/84) in the high risk group. (2) Treatment efficacy: 84 cases were followed up until May 30, 2018. The follow-up time was 42.0 (0.3-120.0) months. The sensitivity rate of prednisone treatment was 56% (47/84); the complete response (CR) rate after the induction therapy of vincristine+daunoblastina+L-asparaginase+dexamethasone (VDLD)(d 33) was 88% (74/84); the total CR rate after VDLD induction combined with cyclophosphamide+cytarabine+6-mercaptopurine (CAM) treatment (d80) was 94% (79/84); the recurrence rate was 24% (20/84). Among the 20 recurrent cases, there were 13 cases (65%) with ultra-early recurrence (within 18 months after diagnosis), 6 cases (30%) with early recurrence (18 to 36 months after diagnosis); 1 patient (5%) with late recurrence (over 36 months after diagnosis). During the follow-up period, twenty-eight children (33%) died (22 cases with recurrence or suspending treatment without remission, 2 cases with infection, 1 case of sudden death in chemotherapy, 1 patient failed in transplantation, 1 patient with severe cirrhosis, and 1 patient with unknown cause). (3) Kaplan-Meier analysis: the 5-year OS and EFS of the 84 children were (63±6)% and (60±6)% respectively. (4) Efficacy in different risk groups: prednisone sensitivity rates in the two different risk groups were 100% (34/34) and 26% (13/50), respectively (χ(2)=3.237, P<0.05). The CR rates at the end of VDLD induction therapy (d 33) were 100% (34/34) and 80% (40/50), respectively (χ(2)=2.767, P<0.05). The recurrence rate of children in the two groups was 12% (4/34) and 32% (16/50), respectively (χ(2)=4.245, P<0.05).The mortality rates of the two groups were 21% (7/34) and 42% (21/50), respectively (χ(2)=3.198, P<0.05). Kaplan-Meier analysis showed that the 5-year OS of the two groups were (77±7)% and (53±8)%; and the 5-year EFS of the two groups were (75±8)% and (49±8)% (χ(2)=4.235, 3.875, both P<0.05) . (5) COX multivariate regression analysis showed that the classification of risk according to CCLG-ALL 2008 was an important factor influencing the prognosis of children with T-ALL (OR=3.313, 95% CI 1.165-9.422, P=0.025). Conclusions: The results of the risk group treatment according to the CCLG-ALL 2008 protocol showed that the long-term survival of children with middle risk was significantly better than that of children at high risk.

[Risk factor analysis on anastomotic leakage after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy and establishment of a nomogram prediction model]

Objective: To investigate the risk factors of anastomotic leakage (AL) after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy and construct a nomogram prediction model. Methods: This study was a retrospective case-control study that collected and reviewed the clinicopathological data of 359 patients who underwent laparoscopic surgery from January 2012 to January 2018, including 202 patients from the Department of General Surgery, Nanfang Hospital of Southern Medical University and 157 patients from the Department of Gastrointestinal Surgery of Fujian Provincial Cancer Hospital. Inclusion criteria: (1) age ≥ 18 years old; (2) diagnosis as rectal cancer by biopsy before treatment; (3) distance from tumor to anus within 12 cm; (4) locally advanced stage (T3-T4 or N+) diagnosed by imaging (CT, MRI, PET or ultrasound); (5) standardized neoadjuvant therapy followed by laparoscopic radical operation. Exclusion criteria: (1) previous history of colorectal cancer surgery; (2) short-term or incomplete standardized neoadjuvant therapy; (3) Miles, Hartmann, emergency surgery, palliative resection; (4) conversion to open surgery. Clinicopathological data, including age, gender, body mass index (BMI), preoperative albumin, distance from tumor to anus, operation hospital, American Society of Anesthesiologists score (ASA score), operation time, T stage, N stage, M stage, TNM stage, pathological complete response (pCR) were analyzed with univariate analysis to identify predictors for AL after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy. Then, incorporated predictors of AL, which were screened by multivariate logistic regression, were plotted by the "rms" package in R software to establish a nomogram model. According to the scale of the nomogram of each risk factor, the total score could be obtained by adding each single score, then the corresponding probability of postoperative AL could be acquired. The area under ROC curve (AUC) was used to evaluate the predictive ability of each risk factor and nomogram on model. AUC > 0.75 indicated that the model had good predictive ability. The Bootstrap method (1000 bootstrapping resamples) was applied as internal verification to show the robustness of the model. The discrimination of the nomogram was determined by calculating the average consistency index (C-index) whose rage was 0.5 to 1.0. Higher C-index indicated better consistency with actual risk. The calibration curve was used to assess the calibration of prediction model. The Hosmer-Lemeshow test yielding a non-significant statistic (P>0.05) suggested no departure from the perfect fit. Results: Of 359 cases, 224 were male, 135 were female, 189 were ≥ 55 years old, 98 had a BMI > 24 kg/m(2), 176 had preoperative albumin ≤ 40 g/L, 128 had distance from tumor to anus ≤ 5 cm, 257 were TNM 0-II stage, 102 were TNM III-IV stage, and 84 achieved pCR after neoadjuvant therapy. The incidence of postoperative AL was 9.5% (34/359). Univariate analysis showed that gender, preoperative albumin and distance from tumor to the anus were associated with postoperative AL (All P<0.05). Multivariate logistic regression analysis revealed that male (OR=2.480, 95% CI: 1.012-6.077, P=0.047), preoperative albumin ≤40 g/L (OR=5.319, 95% CI: 2.106-13.433, P<0.001) and distance from tumor to anus ≤ 5 cm (OR=4.339, 95% CI: 1.990-9.458, P<0.001) were significant independent risk factors for postoperative AL. According to these results, a nomogram prediction model was constructed. The male was for 55 points, the preoperative albumin ≤ 40 g/L was for 100 points, and the distance from tumor to the anus ≤ 5 cm was for 88 points. Adding all the points of each risk factor, the corresponding probability of total score would indicated the morbidity of postoperative AL predicted by this nomogram modal. The AUC of the nomogram was 0.792 (95% CI: 0.729-0.856), and the C-index was 0.792 after internal verification. The calibration curve showed that the predictive results were well correlated with the actual results (P=0.562). Conclusions: Male, preoperative albumin ≤ 40 g/L and distance from tumor to the anus ≤ 5 cm are independent risk factors for AL after laparoscopic surgery in rectal cancer patient with neoadjuvant therapy. The nomogram prediction model is helpful to predict the probability of AL after surgery.

[Clinicopathological features and prognosis of pediatric alveolar rhabdomyosarcoma]

Objective: To investigate the clinicopathological features, diagnosis, differential diagnosis, treatment and prognosis of pediatric alveolar rhabdomyosarcoma (ARMS). Methods: The clinical and pathological data of 25 pediatric ARMS from 2008 to 2018 in Children's Hospital of Fudan University were collected. This histomorphology was assessed, and FOXO1 gene rearrangement was detected with FISH. The treatment details and outcome were analyzed. Results: There were 13 males and 12 females, with ages range from 19 days to 14 years (median 6 years, mean 6.2 years). The ARMS were located in the limbs (13 cases), head and neck (4 cases), trunk (3 cases), abdominal cavity (3 cases), scrotum (1 case) and perianal region (1 case). The ARMS were classified histologically as classic group (18 cases), solid group (5 cases) and embryonic-alveolar mixed group (2 cases). The typical pathological characteristics were small dark round cells arranged in solid, glandular and papillary patterns. The tumor cells expressed ALK (D5F3) (21/25, 84.0%), muscle origin DES (23/25, 92.0%), myogenin (22/25, 88.0%), MYOD1 (19/25, 76.0%), and in some cases they also expressed neurogenic marker Syn (6/25, 24.0%). FOXO1 gene rearrangement was detected by FISH in 24/25 cases (96.0%). Conclusion: Pediatric ARMS is rare and has unique clinicopathological characteristics, and needs to be differentiated from other common small round cell malignancies in children. ALK, DES, myogenin, MYOD1 immunohistochemistry and FOXO1 gene rearrangement are valuable aid in the diagnosis of ARMS.

[Advances and clinical application of lens regeneration in mammal]

Regeneration of the lens is an ideal strategy for cataract patients to restore their adjustable vision and to acquire excellent visual quality. However, mammalian lens regeneration is slow and incomplete, and functional lens regeneration cannot be achieved. The ability of lower amphibians (such as newts) to regenerate the lens provides the impetus for research on the regeneration of the lens of mammal. At present, the main form of mammalian lens regeneration is the differentiation of lens epithelial cells by capsular bag as a scaffold. In recent years, the continuous development of stem cell technology, tissue engineering and biological materials have made great progress in lens regeneration. This article describes the processes in the normal development of the lens, and reviews the research results of lens regeneration at home and abroad, and discusses the possibility of the new techniques and methods related to regenerative medicine applied to lens regeneration. It is hoped to help in the realization of rapid and complete regeneration of functional lens.(Chin J Ophthalmol, 2019, 55: 549-553).

[Factors associated with fatigue in the employees of internet companies]

Objective: To explore factors associated with fatigue in employees working in Internet companies. Methods: A cross-sectional study was conducted among 3603 employees from 35 internet companies. A self-conducted questionnaire was used to assess employees' fatigue and related factors. Results: The scores of body fatigue, mental fatigue and total fatigue were (4.53±2.56) , (2.37±1.64) , and (6.90±3.55) respectively. The body fatigue is positively correlated with job burnout and musculoskeletal disorders (r=0.426, 0.485) ; the mental fatigue is positively correlated with job burnout (r=0.429) . JDC and ERI occupational stress, burnout and high level of musculoskeletal disorders increased the risk of body fatigue of which odds ratios are 1.58, 1.72, 4.08 and 5.91; odds ratios for the risk of mental fatigue are 1.73, 1.37, 2.61 and 2.08. Sleep time over 7 hours reduces the risk of fatigue (P<0.05) with odds ratio of 0.61 and 0.62. Conclusion: Employees of Internet companies is facing fatigue issues. To protect employee's physical and mental health is highly important for employers to alleviate fatigue and improve work performance.