Objective:Based on the specific cleavage and non-specific "trans-cleavage" activities of the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein(CRISPR/Cas13), we established a visually amplification-free rapid detection technique of 2019-nCoV nucleic acid. This technique is easily processed with a low detection limit and good specificity.Methods:According to the 2019-nCoV gene sequence, specific CRISPR RNAs were screened and designed by bioinformatics analysis, and then synthesized as universal signal-strained RNA transcription targets in vitro to establish and optimize the reaction system. Moreover, the 2019-nCoV pseudoviral nucleic acid was used as a standard substance to evaluate the detection limit. A total of 65 positive samples were collected from various 2019-nCoV variants, while 48 negative samples included other clinically common respiratory pathogens, such as influenza A virus, influenza B virus, human parainfluenza virus, Klebsiella pneumonia, etc. All samples were tested by quantitative PCR (qPCR), digital PCR, and the method established in this study. The sensitivity and specificity of the newly established method were analyzed and evaluated. Results:With the newly established technique, the detection time for 2019-nCoV nucleic acid could be minimized to 6 minutes. In addition, the detection limit was 14 copies/μl when assisted by the displaying instrument, whereas it increased to 28 copies/μl with the naked eye. This technique had a sensitivity and specificity of 98.5% (66/67) and 100% (46/46) respectively, showing no statistically significant difference compared to the gold standard qPCR( P=1). Conclusions:This study has successfully established a CRISPR/Cas13a-based visually rapid detection technique for 2019-nCoV nucleic acid. This technique offers the advantages of a simple process, convenient operation, low environmental operating requirements, a detection limit close to qPCR, and a strong potential for on-site testing applications.

OBJECTIVE To investigate the factors influencing the changes in purchasing quantity in the procurement varieties of the first batch of volume-based drug centralized procurement （hereinafter referred to as centralized procurement）. METHODS Using 25 procurement varieties of the “4+7” policy as research objects， the changes in purchasing quantity of procurement varieties were analyzed before and after the implementation of the “4+7” pilot， renewal and expansion policies. The influential factors were determined from the three levels of drugs， medical institutions and regions； and the multiple linear regression model was used to analyze the influential factors for the changes in the purchasing quantity of procurement varieties. RESULTS Before and after the implementation of the “4+7” pilot， renewal and expansion policies， the purchasing quantity increased by 52.1， －0.2， 85.8 ten thousand DDDs on average， compared with base period. During pilot， renewal and expansion period， DDDc decrease in procurement varieties was positively correlated with the increase in purchasing quantity （P＜0.01）. During the pilot and renewal period， the number of absolutely alternative varieties was positively correlated with the increase in purchasing quantity （P＜0.1）. During the pilot and expansion period， the number of alternative varieties to a certain extent was negatively correlated with the increase in purchasing quantity （P＜0.05）. During the renewal period， the increment of purchasing quantity in tertiary hospitals was smaller than that of primary medical institutions （P＜0.05）. CONCLUSIONS There is a relationship between the decline of DDDc and the changes in the purchasing quantity， that is， the more the drug price dropped， the more the purchasing quantity increased. The number of alternative varieties for centralized procurement will affect the changes in their purchasing quantity， but it is not always stable. With the implementation of the policy， the volume of primary medical institutions gradually exceeds that of tertiary institutions， indicating that the consumption of centralized purchased varieties is transferred to the primary medical institutions， and centralized procurement has promoted the implementation of the hierarchical diagnosis and treatment system.

Background In the Global Burden of Disease research, it has been found that atmospheric fine particulate matter (PM_2.5) pollution significantly harms human health. Currently, there is limited research on polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) that exhibit high toxicity effects in PM_2.5 . Objective By studying the spatiotemporal distribution and variation characteristics of PCDD/Fs in PM_2.5 in Pudong area of Shanghai, to assess the associated population health risk. Methods This study set up 28 sampling points in Pudong area. One sample of PM_2.5 was collected during winter (February 2022) and summer (July 2022) at each site, with a sampling period lasting 24 h. The concentration of PM_2.5 was measured by membrane filter method, and the content of 17 kinds of 2,3,7,8-substituted chlorinated PCDD/Fs in the samples was analyzed using isotope dilution. Seasonal variations (winter and summer) in the concentrations of PM_2.5 and PCDD/Fs were evaluated, sources of PCDD/Fs pollution were tracing by principal component analysis, and health risks to the population from respiratory exposure to PCDD/Fs were estimated by VLIER-HUMAAN model. Results The PM_2.5 concentrations in the 28 samples ranged from 10 to 126 μg·m⁻³, while the concentrations of PCDD/Fs in PM_2.5 ranged from 58 to 2625 fg·m⁻³. The concentration of PM_2.5 during winter (11-126 μg·m⁻³) was higher than that during summer (10-60 μg·m⁻³). The concentration range of PCDD/Fs in winter was from 58 to 2625 fg·m⁻³, which corresponded to a range of toxic equivalent quantity (WHO-TEQ) concentration from 2.99 to 40.97 fg·m⁻³ when taking World Health Organization's toxic equivalency factor (WHO-TEQ); the concentration range of PCDD/Fs in summer was from 72 to 446 fg·m⁻³, which corresponded to a range of WHO-TEQ concentration from 2.66 to 16.61 fg·m⁻³. This range in summer was significantly lower than that observed in winter. The results of principal component analysis revealed that waste incineration was the primary source of PCDD/Fs in winter PM_2.5 in the area, whereas traffic emissions emerged as the main source in summer. The assessment of Pudong residents' respiratory exposure to PCDD/Fs in PM_2.5 showed significantly higher exposure of children in summer and winter than that of adults, indicating higher susceptibility of children to air pollutants. Both the hazard ratios (HR) for children and adults were below 1, while the cancer risks (CR) ranged from 8.41×10⁻⁸ to 2.35×10⁻⁶. Notably, during winter, the CR at 4 locations slightly exceeds 1×10⁻⁶, indicating a potential carcinogenic risk. Conclusion The overall pollution level of PCDD/Fs in PM_2.5 in Pudong area is relatively low, but it shows clear seasonal patterns. Waste incineration and traffic are the main sources of PCDD/Fs in PM_2.5 in the area. Although the cancer risk of exposure to PCDD/Fs in PM_2.5 for children or adults is relatively low, there is a certain risk at some locations in winter, necessitating additional monitoring and control.

Cancer-related fatigue (CRF) is a symptom associated with cancer and cancer treatment. The incidence of CRF during radiotherapy is extremely high and severely affects the quality of life and treatment compliance of patients. Although more and more studies on CRF have been carried out, the pathogenesis of CRF caused by radiotherapy is still not well understood, and systemic interventions remain to be improved. In this article, the pathogenesis, influencing factors, and interventions of CRF caused by radiotherapy were reviewed, aiming to provide reference for optimizing treatment options in clinical practice.

Objective:To investigate the efficacy and safety of comprehensive therapy in the treatment of advanced unresectable hepatocellular carcinoma.Methods:Clinical data of 34 patients with primary liver cancer admitted to Peking Union Medical College Hospital from Nov 2018 to Dec 2020 initially evaluated as unresectable were treated firstly by combined therapy and then underwent reevaluation for further management.Results:A total of 34 patients completed the integrative treatment, and no serious adverse events occurred. Among them, 6 patients were evaluated as partial remission, and underwent successful tumor resection, tumors in 7 patients were stable, and 21 patients suffered from disease progression.Conclusion:After comprehensive therapy, unresectable tumors in some patients could reduce and be rendered resection.

Objective:To investigate the efficacy of a machine learning model based on radiomics of brain lesions on T 2WI in differentiating multiple sclerosis (MS) from neuromyelitis optica spectrum disorders (NMOSD). Methods:Totally 223 MS and NMOSD patients who were treated from January 2009 to September 2018 in Beijing Tiantan Hospital Affiliated to Capital Medical University, Donghu Branch of the First Affiliated Hospital of Nanchang University, Tianjin Medical University General Hospital, and Xuanwu Hospital of Capital Medical University were analyzed retrospectively, and according to the proportion of 7∶3, 223 patients were completely randomly divided into training set (156 cases) and test set (67 cases). A total of 74 patients with MS and NMOSD who were treated in Huashan Hospital Affiliated to Fudan University and China-Japan Friendship Hospital of Jilin University from January 2009 to September 2018 and in Xianghu Branch of the First Affiliated Hospital of Nanchang University from March 2020 to September 2021 were collected as an independent external validation set. All patients underwent brain cross-sectional MR T 2WI, radiomics features were extracted from T 2WI, and features were selected by max-relevance and min-redundancy and least absolute shrinkage and selection operator algorithms. Then various machine learning classifier models (logistic regression, decision tree, AdaBoost, random forest or support vector machine) were constructed to differentiate MS from NMOSD. The area under curve (AUC) of receiver operating characteristics was used to evaluate the performance of each classifier model in the training set, test set and external validation set. Results:Based on multi-center T 2WI, a total of 11 radiomics features related to the discrimination between MS and NMOSD were extracted and classifier models were constructed. Among them, the random forest model had the best efficiency in distinguishing MS from NMOSD, and its AUC values for distinguishing MS from NMOSD in the training set, test set and external validation set were 1.000, 0.944 and 0.902, with specificity of 100%, 76.9% and 86.0%, and sensitivity of 100%, 92.1% and 79.7%, respectively. Conclusion:The random forest model based on the radiomic features of T 2WI of brain lesions can effectively distinguish MS from NMOSD.

Objective:To study the clinical characteristics of cornual pregnancy and compare the effects of various surgical methods on the outcomes.Methods:This was a single-center retrospective study. The clinical records of patients with cornual pregnancy who underwent surgery in Peking Union Medical College Hospital from June 2012 to December 2020 were collected. Surgical interventions included curettage (guided by ultrasound or monitored by laparoscope), and cornuostomy/cornectomy (the surgical approach by laparoscopy or laparotomy). The baseline data, perioperative treatment and whether persistent ectopic pregnancy (PEP) occurred after surgery were collected and analyzed statistically.Results:A total of 109 patients with cornual pregnancy diagnosed by surgical treatment were included in this study, whose average age was (32.9±4.8) years. Among them, the incidence of postoperative PEP was 16.5% (18/109). The risk of PEP in multipara was significantly higher than that in nulliparous women ( OR=7.639, 95% CI: 2.063-28.279, P=0.001). The risk of PEP in patients with the maximum diameter of lesion<1.5 cm was significantly higher than that in patients with the maximum diameter of lesion≥1.5 cm ( OR=8.600, 95% CI: 2.271-32.571, P=0.002). Among all surgical approaches for cornual pregnancy, the proportion of PEP in curettage under ultrasound monitoring was the highest (56.0%, 14/25), which was higher than that in curettage under laparoscope monitoring (1/10; χ2=6.172， P=0.013); the proportion of PEP in curettage group (42.9%, 15/35) was higher than that in cornuostomy/cornectomy group (4.1%, 3/74; χ2=25.950， P<0.01). Neither salpingectomy in the operation nor the routine use of methotrexate (MTX) in perioperative period could significantly reduce the incidence of PEP (all P>0.05). Conclusions:Among the patients with cornual pregnancy, multipara, the maximum diameter of lesion<1.5 cm and ultrasound-guided curettage are the risk factors of PEP after operation. Cornuostomy or cornectomy is recommended for patients with cornual pregnancy. If the patients would perform the curettage operation, laparoscopic monitoring is recommended. For patients with possible satisfactory operation outcome, it is not recommended to use MTX as a routine preventing measure.

Objective:To investigate the role and mechanism of retinal Sigma-1 receptor antagonist N, N-diethyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]ethanaminehydrochloride (NE-100) in the formation of form deprivation myopia (FDM) in guinea pigs.Methods:Eighty-five 21-day-old guinea pigs were selected, and 36 of them were randomly divided into normal control group, occluded 14-day group and occluded 11-day group, with 12 in each group.The right eyes of guinea pigs in the occluded 14-day group were covered with translucent eye shield for consecutive 14 days, and guinea pigs in the occluded 11-day group were treated in the same way for consecutive 11 days plus 3 days without cover, and guinea pigs in the normal control group were not covered.The other 49 guinea pigs were randomly divided into FDM group ( n=10), FDM+ NE-100 6 μg group ( n=12), FDM+ NE-100 60 μg group ( n=10), FDM+ NE-100 600 μg group ( n=9), and FDM+ saline group ( n=8). The right eyes in each group received 100 μl peribulbar injection of NE-100 6 μg, 60 μg and 600 μg or saline once a day according to grouping.Ocular refraction and axial dimensions were measured using eccentric infrared photorefractor and A-scan ultrasonography, respectively.Corneal curvature was measured with keratometer.Immunohistochemical staining and Western blot were used to detect the expression levels of Sigma-1 receptor protein, and retinal dopamine content was evaluated by high-performance liquid chromatography with electrochemical detection.This study was approved by an Ethics Committee of the Department of Laboratory Animal Science of Central South University (No.2020sydw0084). The use and care of experimental animals followed the Regulations for the Administration of Affairs Concerning Experimental Animals in China. Results:There were statistical significant differences in diopter and axial length among the normal control group, occluded 14-day group and occluded 11-day group ( F=147.81, 160.10; both at P<0.01). Compared with the normal control group, the relative myopia was the deepest and the axial length was the longest in the occluded 14-day group, then the occluded 11-day group, showing significant differences between them (all at P<0.05). In the normal control group, Sigma-1 protein was mainly expressed in retinal ganglion cells (RGCs), photoreceptor inner segment and the inner nuclear layer.In the occluded 14-day group, Sigma-1 protein staining was enhanced in RGCs and photoreceptor inner segment.Sigma-1 staining positive cells in the inner nuclear layer were increased significantly and were also seen in the inner and outer plexiform layers, especially in Müller cells, in which the expression levels of Sigma-1 receptor protein were significantly increased.Compared with the occluded 14-day group, the Sigma-1 receptor protein expression levels in the retina of the occluded 11-day group was significantly decreased ( P<0.01). The diopters of guinea pigs in the FDM+ NE-100 6 μg, 60 μg and 600 μg groups were lower than those in the FDM group, and the diopters of FDM+ NE-100 60 μg and 600 μg guinea pigs were lower than those in the FDM+ NE-100 6 μg group, and the differences were statistically significant (all at P<0.05). The dopamine content in the retina of the FDM+ NE-100 60 μg group was (0.74±0.09) ng/mg, which was significantly higher than (0.57±0.10) ng/mg in the FDM group, with a significant difference between them ( t=15.18, P<0.01). Conclusions:Sigma-1 receptor antagonist inhibits FDM formation, which may be associated with the elevation of dopamine content in retina.

Objective:To examine the surgical treatment of Stanford type A aortic dissection (type A dissection) after thoracic endovascular aortic repair (TEVAR).Methods:The data of 58 patients with reoccurrence of type A dissection after TEVAR admitted into the Department of Cardiovascular Surgery, Henan Chest Hospital from February 2012 to January 2020 were analyzed retrospectively. There were 40 males and 18 females, aged (57.0±6.7) years (range: 31 to 71 years). The time between recurrence of type A dissection and TEVAR ( M( Q R)) was 37 days (72.8 months) (range: 1 h to 14 years). Forty-eight cases underwent emergency operation, 9 cases underwent sub-emergency operation, and 1 case died of dissection rupture on the way to the operating room. All 57 patients underwent radical treatment. Fifty-four cases underwent the frozen elephant trunk technique under deep hypothermia circulatory arrest and selective cerebral perfusion, and 3 cases (>65 years old) underwent arch debranch anastomosis+ascending aorta replacement+descending arch covered stent implantation under mild hypothermia. Results:The operation time was (445±32) minutes (range: 382 to 485 minutes), the aortic crossclamp time was (103±19) minutes (range: 89 to 133 minutes), the cardiopulmonary bypass time was (189±27) minutes (range: 162 to 221 minutes), and the intraoperative blood loss was (665±343) ml (range: 450 to 1 750 ml). Postoperative ICU stay time was 5 (6) days (range: 2 to 27 days), and postoperative hospital stay was 14.0 (4.5) days (range: 2 to 36 days). Three cases died, including 2 cases with severe brain complications and 1 case with systemic multiple organ failure caused by severe liver insufficiency and gastrointestinal hemorrhage. Postoperative follow-up was 0.5 to 7.0 years, which showed that 1 case had left coronary artery anastomotic stoma fistula 3 months after operation and underwent reoperation, 2 cases underwent thoracoabdominal aortic replacement again, and the rest of patients had no anastomotic stoma fistula and incomplete stent distortion and expansion on CT angiography. Four cases died during follow-up, and 1 case died of sudden cerebral infarction 2 years after operation.Conclusion:The recurrent type A dissection after TEVAR is mostly related to stent graft, and the patients can undergo operation actively with good prognosis.

Objective:To examine the surgical treatment of Stanford type A aortic dissection (type A dissection) after thoracic endovascular aortic repair (TEVAR).Methods:The data of 58 patients with reoccurrence of type A dissection after TEVAR admitted into the Department of Cardiovascular Surgery, Henan Chest Hospital from February 2012 to January 2020 were analyzed retrospectively. There were 40 males and 18 females, aged (57.0±6.7) years (range: 31 to 71 years). The time between recurrence of type A dissection and TEVAR ( M( Q R)) was 37 days (72.8 months) (range: 1 h to 14 years). Forty-eight cases underwent emergency operation, 9 cases underwent sub-emergency operation, and 1 case died of dissection rupture on the way to the operating room. All 57 patients underwent radical treatment. Fifty-four cases underwent the frozen elephant trunk technique under deep hypothermia circulatory arrest and selective cerebral perfusion, and 3 cases (>65 years old) underwent arch debranch anastomosis+ascending aorta replacement+descending arch covered stent implantation under mild hypothermia. Results:The operation time was (445±32) minutes (range: 382 to 485 minutes), the aortic crossclamp time was (103±19) minutes (range: 89 to 133 minutes), the cardiopulmonary bypass time was (189±27) minutes (range: 162 to 221 minutes), and the intraoperative blood loss was (665±343) ml (range: 450 to 1 750 ml). Postoperative ICU stay time was 5 (6) days (range: 2 to 27 days), and postoperative hospital stay was 14.0 (4.5) days (range: 2 to 36 days). Three cases died, including 2 cases with severe brain complications and 1 case with systemic multiple organ failure caused by severe liver insufficiency and gastrointestinal hemorrhage. Postoperative follow-up was 0.5 to 7.0 years, which showed that 1 case had left coronary artery anastomotic stoma fistula 3 months after operation and underwent reoperation, 2 cases underwent thoracoabdominal aortic replacement again, and the rest of patients had no anastomotic stoma fistula and incomplete stent distortion and expansion on CT angiography. Four cases died during follow-up, and 1 case died of sudden cerebral infarction 2 years after operation.Conclusion:The recurrent type A dissection after TEVAR is mostly related to stent graft, and the patients can undergo operation actively with good prognosis.