[Clinical characteristics of convalescent children infected with SARS-CoV-2 Omicron variant in Tianjin]

Objective: To analyze the clinical characteristics of SARS-CoV-2 Omicron variant infected children in convalescence in Tianjin. Methods: A total of 104 pediatric patients infected by SARS-CoV-2 Omicron variant Tianjin First Central Hospital (designated hospital for SARS-CoV-2 infection in Tianjin) for convalescent treatment from January 22^nd, 2022 to February 24^th were included for a retrospective study.Clinical data including clinical typing, SARS-CoV-2 IgG and IgM test and 2019-nCoV nucleic acid test were collected.The cases were divided into 2-dose group and zero-dose group based on the doses of inactivated SARS-CoV-2 vaccine. The children were divided into repositive group and negative group, according to the nucleic acid test during hospitalization. Chi-square test was used for the comparison between the groups. Results: The age of these 104 children was 10.0 (0.3, 14.0) years on admission, 53 children were males and 51 were females, 92 cases (88.5%) had mild symptoms, 12 cases (11.5%) had common symptoms.The age and SARS-CoV-2 IgG level of zero-dose group was lower (2.0 (0.3, 10.2) vs. 10.0 (3.2, 14.0) years, 10 (2, 17) vs. 193 (157, 215), χ²=-5.57, Z=-48.76,both P<0.001) than that of 2-dose group. The zero-dose group had a high rate of transmission among family members and a high level of SARS-CoV-2 IgM level (13/14 vs. 62.2% (56/90), 0.4 (0.2, 0.8) vs. 0.4 (0.2, 1.1),χ²=5.09, Z=-48.95, both P<0.05) than the 2-dose group. Repositive group had a high rate of underlying diseases and SARS-CoV-2 IgM level was higher (2/13) vs. 1.1% (1/91), (0.6 (0.2, 1.0) vs. 0.3 (0.2, 0.7), χ²=8.29, Z=2.70, both P<0.05) than negative group. The SARS-CoV-2 IgG level of repositive group was lower than that of negative group (160 (78, 197) vs. 213 (186, 231), χ²=-3.20, P<0.05). Conclusions: Children infected with SARS-CoV-2 Omicron variant in Tianjin were mainly transmitted by family members, and most of them had mild symptoms. Two-dose group had higher IgG levels and lower IgM levels than zero-dose group.The probability of SARS-CoV-2 nucleic acid test repositivity increased in children with underlying diseases and lower IgG levels.

[Interpretation of defeating meningitis by 2030: a global road map]

Meningitis is a life-threatening disease. In order to reduce its threat to public health, the World Health Assembly indorsed a resolution in 2020 for urgent global action to prevent and control meningitis. Defeating Meningitis by 2030: a Global Roadmap was officially launched by the World Health Organization in 2021. We interpreted some key information of the roadmap from the aspects of coverage, objectives and pillar strategies, providing ideas for further strengthening the prevention and control of bacterial meningitis in China.

[Cone-beam CT analysis of the correlation between incisor root resorption rate and tooth movement index in adult patients with fixed orthodontics appliance]

Objective: To analyze the correlation between the root resorption rate and tooth movement of the maxillary and mandibular incisors before and after orthodontic treatment in adult patients using cone-beam CT (CBCT), and to explore the related factors that affect the apical root resorption. Methods: In this retrospective study, 23 adult patients with classⅠor class Ⅱ division 1 malocclusion [2 males and 21 females, mean age (23.4±6.3) years, treatment time (2.1±0.7) years] who received orthodontic treatment with fixed appliance in Department of Oral & Cranio-Maxillofacial Surgery, Shanghai Ninth People's Hospital from January 2017 to June 2021 were enrolled. Full-column CBCT examination was performed before and after treatment. A three-dimensional model was established to observe and record the volume of the maxillary and mandibular central and lateral incisors before and after treatment. The change of the incisal edge, the angle of rotation of the incisal edge, and the direction of the long axis of the tooth were also measured. The root resorption in each tooth before and after treatment was compared, and the root resorption rate was calculated. Pearson correlation analysis was performed on the root absorption rate before and after treatment with age, treatment time and tooth movement. Results: After treatment, the tooth volume of the maxillary and mandibular central and lateral incisors decreased significantly (P<0.01). The root absorption volumes were (20.2±6.0) mm3 and (11.2±4.7) mm3 in maxillary central and lateral incisors, and (14.7±4.6) mm3 and (14.8±5.0) mm3 in mandibular central and lateral incisors, respectively. The root absorption rates were (9.49±1.75)% and (9.13±3.24)% in maxillary central and lateral incisors, and (8.56±3.43)% and (9.13±3.24)%, in mandibular central and lateral incisors, respectively (F=0.56, P=0.640). The root resorption rate of maxillary central incisors had a weak positive correlation with the change of sagittal distance of incisal edge (r=0.36, P=0.015). The root resorption rate of mandibular central incisors had a moderate positive correlation with the vertical movement distance (r=0.48, P=0.001). The root resorption rate of mandibular lateral incisors was weakly positively correlated with the vertical movement of incisal edge and the treatment time (r=0.35, P=0.016; r=0.34, P=0.021), and was moderately positively correlated wit the change of sagittal movement of incisal edge (r=0.44, P=0.002). Conclusions: During orthodontic treatment, both maxillary and mandibular incisors had a certain degree of root resorption, which was related to sagittal and vertical movement of the incisors and the time of orthodontic treatment.

[Stereotactic body radiation therapy for patients with lung and liver oligometastases from colorectal cancer: a phase Ⅱ trial]

Objective: To explore the safety and effectiveness of stereotactic body radiation therapy (SBRT) for oligometastases from colorectal cancer (CRC). Methods: This is a prospective, single-arm phase Ⅱ trial. Patients who had histologically proven CRC, 1 to 5 detectable liver or lung metastatic lesions with maximum diameter of any metastases ≤5 cm were eligible. SBRT was delivered to all lesions. The primary endpoint was 3-year local control (LC). The secondary endpoints were treatment-related acute toxicities of grade 3 and above, 1-year and 3-year overall survival (OS) and progression free survival (PFS). Survival analysis was performed using the Kaplan-Meier method and Log rank test. Results: Petients from 2016 to 2019 who were treated in Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Forty-eight patients with 60 lesions were enrolled, including 37 liver lesions and 23 lung lesions. Forty-six patients had 1 or 2 lesions, with median diameter of 1.3 cm, the median biologically effective dose (BED(10)) was 100.0 Gy. The median follow-up was 19.5 months for all lesions. Twenty-five lesions developed local failure, the median local progression free survival was 15 months. The 1-year LC, OS and PFS was 70.2% (95% CI, 63.7%~76.7%), 89.0% (95% CI, 84.3%~93.7%) and 40.4% (95%CI, 33.0%~47.8%). The univariate analysis revealed that planning target volume (PTV) and total dose were independent prognostic factors of LC (P<0.05). For liver and lung lesions, the 1-year LC, OS and PFS was 58.7% and 89.4% (P=0.015), 89.3% and 86.5% (P=0.732), 30.5% and 65.6% (P=0.024), respectively. No patients developed acute toxicity of grade 3 and above. Conclusion: SBRT is safe and effective treatment method for oligometastases from CRC under precise respiratory motion management and robust quality assurance.

The role of metal ions in the behavior of bovine serum albumin molecules under physiological environment

Metal ions released from metallic implants can affect the conformation and structural stability of proteins in biological fluids, which eventually affects the biocompatibility of implants. The present study aimed at understanding the interactions between the metal ions (Mn²⁺, Fe²⁺, Fe³⁺, Co²⁺, Cu²⁺, and Zn²⁺) and bovine serum albumin (BSA) molecules in physiological context. The structural information of BSA molecules and the microenvironment of functional groups were investigated using UV, Raman, and circular dichroism spectroscopy. The results revealed that addition of Fe³⁺, Fe²⁺, and Cu²⁺ ions alters the tertiary structure of BSA molecules and exposes the aromatic heterocyclic hydrophobic group of BSA amino acid residues. The addition of Fe³⁺ and Cu²⁺ ions results in increased viscosity and decreased intensity of the water peak in the BSA solution. Furthermore, Fe³⁺ and Cu²⁺ ions evidently promote the α-helix to β-sheet transformation of BSA molecules due to decreased disulfide bond stability. Tryptophan residues of BSA and metal ions containing BSA (Me⁺/BSA) solutions were found to be in a hydrophilic environment. Moreover, the addition of metal ions to BSA results in several of tyrosine residues acting as hydrogen-bond donors. Coomassie brilliant blue staining revealed that the addition of Cu²⁺ ions promotes the aggregation of BSA molecules. The findings of this study will be helpful for evaluating the biocompatibility of metallic implants.

[Help-seeking efficacy and the intention of social assistance among medical care personnel during the major public health events]

Objective: To explore the help seeking efficacy and social assistance willingness of medical staff during major public health events, so as to provide basis for improving the psychological resources and service quality of medical staff and further optimizing the prevention and treatment policies. Methods: In February 2020, a convenient sampling method was used to conduct an online questionnaire survey on medical staff in Henan Province, and a total of 2136 questionnaires were collected. Among them, there were 1940 valid questionnaires, and the effective recovery rate was 90.82%. The questionnaire of help seeking efficacy and willingness to social assistance under epidemic situation was used to investigate the help seeking efficacy and willingness of medical staff. The frequency and rate (%) were used to analyze the overall situation of medical staff's help seeking efficacy and social assistance willingness. The differences among different demographic variables were tested by χ(2) test. Results: Among the 1940 medical and nursing staff, 18.81% (365/1940) did not know how to obtain appropriate psychological assistance. Compared with the low age group, the medical staff in the high age group had the ability of information query, the ability to occupy knowledge resources, the ability to distinguish rumors and facts and the sense of efficacy of obtaining appropriate medical help, and the difference was statistically significant (P<0.05) . The willingness of medical and nursing staff to actively cooperate with the government, maintain social stability and volunteer work were 99.43% (1929/1940) , 98.81% (1917/1940) and 97.11% (1884/1940) . Conclusion: The medical staff had a higher sense of help seeking efficacy and willingness to social assistance. It is necessary to further strengthen the resource support of psychological, social and humanistic care for medical staff.

[Proportion and rate: connotation and understanding route]

Proportion and rate have multiple and overlapping meanings, which blur their concepts. Based on the existence of the states and the occurrence of the events and their measuring process, we first put forward the concept of "cumulative number of states in point time". Considering the general meaning of "rate" in mathematics and the units of the elements in indexes, this paper puts forward the concept of "the change of cumulative number of states in point time", which is equal to the commonly acknowledged concept "number of incident event within observation period" or "absolute rate", and further constructs relative rate and proportion. Proportions can be classified into three types: time-point (or rate-type) constitutional proportion, time-period incidence proportion and their synthesis, time-period constitutional proportion. The essential difference between relative rate and time-period proportions is whether the observation period is regarded as a one-unit-length fixed period which would be further moved to the description of the indexes. Furthermore, the sources populations of relative rate and proportions are exclusively those at the beginning of the observation period. Thus, we established a unified identification route about ratios, proportions, and rates, the basic indicators of categorical data in populations. These are applicable to both fixed and dynamic populations. The paper aims to clarify the connotation of the indexes and the feasible understanding route and provide some reference for the population researchers.

[A new classification of maxillary defect and simultaneous accurate reconstruction]

Objective: To select the preferred flaps for the reconstruction of different maxillary defects and to propose a new classification of maxillary defects. Methods: A total of 219 patients (136 males and 83 females) underwent the simultaneous reconstruction of maxillary defects in the Beijing Tongren Hospital, Capital Medical University, between January 2005 and December 2018 were reviewed. Age ranged from 16 to 78 years. Based on the proposed new classification of the maxillary defects, 22 patients with class Ⅰ defects (inferior maxillectomy), 44 patients with class Ⅱ defects (supperior maxillectomy), 132 patients with class Ⅲ defects (total maxillectomy) and 21 patients with class Ⅳ defects (extensive maxillectomy) were enrolled. Survival rate, functional and aesthetic outcomes of flaps were evaluated. Survival analysis was performed in 169 patients with malignant tumor, Kaplan-Meier method was used to calculate the survival rate, and Log-rank method was used to compare the difference of survival rate in each group. Results: A total of 234 repairs for maxillary defects were performed in 219 patients. Fibula flaps were used in 4/13 of class Ⅰ defects; temporal muscle flaps (11/24, 45.8%) and anterolateral thigh flaps (6/24, 25.0%) used in class Ⅱ defects; temporal muscle flaps (71/128, 55.5%), anterolateral thigh flaps (6/24, 25.0%) and fibula flaps (12/128, 9.4%) used in class Ⅲ defects; and anterolateral thigh flaps (8/20, 40.0%) and rectus abdominis flaps (8/20, 40.0%) used in class Ⅳ defects. The success rate of local pedicled flaps was 95.6% (109/114) and that of free flaps was 95.8% (115/120). Thrombosis(10/234,4.3%) was a main reason for repair failure. Among the followed-up 88 patients, swallowing and speech functions recovered, 82 (93.2%) of them were satisfied with appearance, and 75 (85.2%) were satisfied with visual field. The 3-year and 5-year overall survival rates were 66.5% and 63.6%, and the 3-year and 5-year disease-free survival rates were 57.1% and 46.2%, respectively, in the 169 patients with malignant tumors. Conclusion: A new classification of maxillary defects is proposed, on which suitable flaps are selected to offer patients good functional and aesthetic outcomes and high quality of life.

[The expression of clock gene CLOCK and its clinical significance in nasopharyngeal carcinoma]

Objective: To explore the relationship between expression levels of CLOCK mRNA and protein and the clinical characteristics of patients with nasopharyngeal carcinoma. Methods: The frozen tissue specimens from 33 patients with nasopharyngeal carcinoma in the Affiliated Tumor Hospital of Guizhou Medical University from 2018 to 2019 were collected. Seventeen cases of tissue specimens from patients with nasopharyngeal chronic inflammation in the Affiliated Hospital of Guizhou Medical University in 2019 were collected. From 2008 to 2014, 68 cases of formalin-fixed paraffin-embedding (FFPE) nasopharyngeal carcinoma tissue and 37 cases of FFPE nasopharyngeal chronic inflammation tissue were collected from the Affiliated Tumor Hospital of Guizhou Medical University. Real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot (WB) were used to detect the mRNA and protein expression levels of CLOCK. The nasopharyngeal carcinoma cells including CNE1, CNE2, 5-8F and the normal nasopharyngeal epithelial cell NP69 were cultured. qRT-PCR was used to detect the expression level of CLOCK mRNA in each cell line at the time points of ZT2, ZT6, ZT10, ZT14, ZT18 and ZT22. The cosine method was used to fit the rhythm of CLOCK gene in nasopharyngeal carcinoma. The protein expression of CLOCK protein was detected by using immunohistochemical method in 68 cases of nasopharyngeal carcinoma and 37 cases of nasopharyngeal chronic inflammation tissue. Survival was analyzed by Kaplan-Meier method and Log rank test, and the influencing factors was analyzed by Cox regression model. Results: The expression levels of CLOCK mRNA in CNE1, CNE2 and 5-8F cells (0.63±0.07, 0.91±0.02 and 0.33±0.04, respectively) were lower than that in NP69 cell (1.00±0.00, P<0.05). The expression levels of CLOCK protein in CNE1, CNE2 and 5-8F cells (0.79±0.06, 0.57±0.05 and 0.74±0.10, respectively) were lower than that of NP69 cells (1.00±0.00, P<0.05). The expressions of CLOCK mRNA in nasopharyngeal carcinoma cells including CEN1, CNE2, 5-8F and normal nasopharyngeal epithelial cell NP69 were different at different time points, with temporal fluctuations. The fluctuation periods of CLOCK mRNA in CNE1, CNE2, 5-8F, and NP69 cells were 16, 14, 22 and 24 hours, respectively. The peak and trough times were ZT10: 40 and ZT18: 40, ZT10 and ZT3, ZT14: 30 and ZT3: 30, ZT12: 39 and ZT0: 39, respectively. CLOCK mRNA and protein expression levels in nasopharyngeal carcinoma tissues (0.37±0.20 and 0.20±0.26, respectively) were lower than those in nasopharyngeal chronic inflammation tissues (1.00±0.00 and 0.51±0.41, respectively, P<0.05). The 1, 3, and 5-year survival rates of patients in the CLOCK protein high expression group (CLOCK protein expression level ≥ 0.178) were 96.2%, 92.1%, and 80.1%, respectively, which were higher than those in the low expression group (CLOCK protein expression level <0.178, 92.9% , 78.6% and 57.1%, respectively, P=0.009). The 1, 3, and 5-year progression-free survival (PFS) rates of patients in the CLOCK protein high expression group were 96.2%, 87.8%, and 87.7%, respectively, which were higher than those in the low expression group (92.7%, 82.2%, and 70.8%, respectively, P=0.105). Compared with the low-expression group (100.0%, 96.9%, and 90.0%, respectively), the 1, 3, and 5-year recurrence-free survival rates of patients in the CLOCK protein high expression group (100.0%, 95.7%, and 95.7%, respectively) were not statistically significant (P=0.514). Compared with the low-expression group (92.7%, 82.2%, and 79.3%), the 1, 3, and 5-year survival rates without metastasis in the CLOCK protein high expression group (96.2%, 92.0%, and 92.0%, respectively) were not statistically significant (P=0.136). CLOCK protein expression and T stage were independent prognostic factors of overall survival (P<0.05). Conclusions: The expression of CLCOK is downregulated in the nasopharyngeal carcinoma cell and nasopharyngeal carcinoma tissues. Clock gene CLOCK is rhythmically expressed in the nasopharyngeal carcinoma cells and normal nasopharyngeal epithelial cells. Compared with normal nasopharyngeal epithelial cells, the fluctuation period of CLOCK in nasopharyngeal carcinoma cells is shortened. The overall survival of patients in the CLOCK protein high expression group is better than that of low expression group. The expression of CLOCK protein is an independent influencing factor for overall survival. CLOCK gene may be a potential tumor suppressor gene in the nasopharyngeal carcinoma.

[Safety analysis of definitive surgery for chronic radiation intestinal injury]

Objective: To investigate the safety of definitive surgery for chronic radiation intestinal injury. Methods: A descriptive case series study was performed. Clinical data of 105 patients who were diagnosed as chronic radiation intestinal injury, had complete data and received definitive surgery (the radiation-induced intestinal segment and digestive tract reconstruction) at Department of Gastrointestinal Surgery of Beijing Tsinghua Changgung Hospital from June 2016 to May 2020 were retrospectively analyzed. There were 30 males (28.6%) and 75 females (71.4%) with the median age of 58 years (P25, P75: 52, 64 years). Patients who had tumor recurrence or refused surgical treatment were excluded. According to the preoperative evaluation and clinical manifestations, to select the resection range. Outcome parameters: (1) preoperative evaluation (nutrition risk assessment and status of obstruction or fistula); (2) clinical manifestations and treatment strategies; (3) details of surgical parameters; (4) postoperative complications, and Clavien-Dindo classification III to V was defined as main moderate-severe complication. Results: (1) Preoperative evaluation: Eighty-eight patients (83.8%) developed symptoms of chronic radiation intestinal injury more than 1 year after the end of radiotherapy. Ninety-eight patients (93.3%) had preoperative NRS-2002 score ≥3, 74 patients (70.5%) received preoperative parenteral nutritional support, and the median time of nutritional support was 10.5 (7.0, 16.0) days. Sixteen patients (15.2%) received small intestinal decompression tube implantation due to severe obstruction. (2) Clinical manifestations and treatment strategies: Among 105 patients, 87 (82.9%) presented with obstruction and received definitive resection of the radiation-induced intestinal segment plus one-stage digestive tract reconstruction; 18 (17.1%) presented with intestinal fistula and all of them received definitive resection of the radiation-induced intestinal segment, intestinal fistula plus one-stage digestive tract reconstruction. Among above 18 patients with fistula, 3 patients with ileorectal stump fistula received pedicled pelvic closure of greater omentum at the same time; 4 patients had ileal vesical fistula, of whom 2 patients received cystectomy and bladder repair due to preoperative nephrostomy decompression, and the other 2 patients received transection of the small intestine proximal and distal to the fistula and anastomosis of the intestinal loop without fistula resection, intestinal fistula or bladder fistula repair. (3) The details of surgical parameters: Median operative time and intraoperative blood loss was 230 (180, 300) minutes and 50 (20, 50) ml respectively. Ninety-two patients (92/105, 87.6%) underwent ileocolonic anastomosis, and anastomosis on the hepatic flexure or splenic flexure colon were performed in 88 (83.8%) and 4 (3.8%) patients respectively. Ileoileal anastomosis was performed in 13 patients (12.4%). The anastomotic site of 92 patients (87.6%) was strictly located in the contralateral quadrant of the radiation field, and the anastomotic site of 13 patients (12.4%) was far from the radiation field. Nine patients (8.6%) had more than one anastomosis, 5 patients (4.8%) had less than 180 cm of residual small intestine, 7 patients (6.7%) underwent retrograde intestinal permutation, 4 patients (3.8%) underwent abdominal wall reconstruction surgery due to abdominal wall defects, and 87 patients (82.9%) had severe abdominal pelvic adhesions (grade 3-4 adhesions). Intraoperative complications occurred in 3 patients (2.9%), which were found in time and handled properly. The median postoperative hospital stay was 13.0 (12.0, 24.5) days, and all the patients had resumed oral feeding upon discharge. (4) Postoperative complications: Fourteen patients (13.3%) had 18 major complications (grade III to V). The incidence of postoperative anastomotic leakage was 5.7% (6/105), and the incidence of anastomotic leakage for ileocolon anastomosis and ileoileal anastomosis was 2.2% (2/92) and 4/13, respectively (χ(2)=17.29, P<0.001). The incidence of postoperative anastomotic leakage of intestinal fistula and intestinal obstruction was 3/18 and 3.4% (3/87), respectively (χ(2)=4.84, P=0.028). The mortality at 30 days after operation was 1.0% (1/105), after abdominal infection and septic shock caused by postoperative anastomotic leakage resulting in multiple organ failure. Conclusion: For chronic radiation intestinal injury patients with obstruction or fistula, definitive surgical treatment is feasible and safe with acceptable major complications.

[Effects of SGLT2i on 24-hour ambulatory blood pressure in patients with type 2 diabetes complicating hypertension: a meta-analysis]

Objective: To analyze the effects of different types of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on 24-hour ambulatory blood pressure in patients with type 2 diabetes mellitus and hypertension. Method: In this meta-analysis, we searched for randomized controlled trials on the effect of SGLT2i on 24-hour ambulatory blood pressure in patients with type 2 diabetes and hypertension. Three databases, namely PubMed, Web of Science and Cochrane Library, were searched. The search was organized on the concept of 3 conceptual groups: the first group contained terms used to describe SGLT2i, the second group contained terms related to blood pressure, and the third group contained terms used to describe randomized controlled trials. The search time was from the establishment of the database to December 2020. The inclusion and exclusion criteria were formulated in accordance with the requirements of the Cochrane systematic review. According to whether the heterogeneity of the study was significant or not, a random effect model or a fixed effect model were used to conduct the analysis on the impact of different types of SGLT2i on 24-hour ambulatory blood pressure and day and night blood pressure in patients with type 2 diabetes and hypertension. Further subgroup analysis was performed to define potential factors, which might lead to clinical heterogeneity. Results: Seven clinical trials were finally included. The result of the meta-analysis showed that compared with placebo group, SGLT2i could reduce the 24-hour dynamic systolic blood pressure of patients with type 2 diabetes and hypertension by 4.36 mmHg (1 mmHg=0.133 kPa). Reduction was 4.59, 3.74, 5.06, and 3.64 mmHg by canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin respectively; SGLT2i could reduce the 24-hour dynamic diastolic blood pressure of patients with type 2 diabetes and hypertension by 2.20 mmHg, and the reduction was 2.30, 1.22, 2.00, and 2.69 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin respectively. SGLT2i could reduce the daytime systolic blood pressure of patients with type 2 diabetes and hypertension by 5.25 mmHg, and reduction was 5.38, 4.87, 6.00, and 4.37 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin, respectively. Simultaneously, SGLT2i could reduce the diastolic blood pressure of patients with type 2 diabetes and hypertension by 2.62 mmHg, and the reduction was 2.56, 2.47, and 2.80 mmHg by canagliflozin, empagliflozin and ertugliflozin, respectively. SGLT2i could reduce the nighttime systolic blood pressure of patients with type 2 diabetes and hypertension by 3.62 mmHg, and the reduction was 2.09, 2.06, 3.92, and 2.45 mmHg by canagliflozin, dapagliflozin, empagliflozin and ertugliflozin, respectively. At the same time, SGLT2i could reduce the nighttime diastolic blood pressure of patients with type 2 diabetes and hypertension by 1.60 and 1.51 mmHg, the reduction was 1.53 and 2.58 mmHg by canagliflozin, empagliflozin and ertugliflozin, respectively. Conclusion: SGLT2i can reduce 24-hour ambulatory blood pressure in patients with type 2 diabetes and hypertension.

[Comparison of preoperative chemotherapy with concurrent chemoradiotherapy combined with TME for 305 patients with locally advanced rectal cancer]

Objective: To retrospectively analyze the long-term efficacy and prognostic factors of preoperative chemotherapy (PCT) or chemoradiotherapy (PCRT) combined with total mesorectal excision in locally advanced rectal cancer. Methods: Clinical pathology data of 305 patients with localized advanced rectal cancer admitted to the Cancer Hospital, Chinese Academy of Medical Sciences from 2006 to 2018 were collected, of whom 246 patients received PCRT (PCRT group), 59 patients received PCT (PCT group). Kaplan-Meier and Log rank test were used for the survival analysis, Cox regression model was used for multivariate analysis, and the prognosis of two groups of patients were compared by the propensity score matching (PSM). Results: In the whole group of 305 patients, 20 cases of tumors located in the upper part of the rectum and at the junction of rectum and colon, 96 cases in the middle of the rectum and 189 cases in the lower part of the rectum. PCRT group included 38 cases of cT2-3 phase, 11 cases of cT4a stage, 10 cases of cT4b stage, while the cases in PCT group were 184, 0 and 62 cases, respectively, the difference is statistically significant (P<0.05). The R0 excision rates of PCRT group and PCT group were 100% (246/246) and 96.6% (57/59), respectively, and the total pathological remission rates were 13.4% and 3.3%, respectively (P<0.05). After PSM, the 3-year survival rates of PCRT group and the PCT group were 86.6% and 89.9% (P>0.05), respectively, and the progression-free survival rates were 74.6% and 77.2% (P>0.05), local recurring free survival rates were 100% and 92.3% (P>0.05), distant metastasis free survival rate were 75.6% and 77.3% (P>0.05). Pre-treatment N-positive, N-degeneration and MRF-positive were all associated with total survival (P<0.05). Conclusion: In the PCRT group, with a higher proportion of patients with stage T4b and lower rectal cancer, the long-term efficacy of PCRT was similar to that of PCT, and higher R0 excision rate and pathological complete response rate could be obtained.

[Outcome of radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type]

Objective: To evaluate the prognosis and determine the failure patterns after radiotherapy for low-risk early-stage patients with extranodal NK/T-cell lymphoma, nasal-type (ENKTCL). Methods: A total of 557 patients from 2000-2015 with low-risk early-stage ENKTCL who received radiotherapy (RT) with or without chemotherapy (CT) from China Lymphoma Collaborative Group were retrospectively reviewed. Among them, 427 patients received combined modality therapy, whereas 130 patients received RT alone. Survivals were calculated by Kaplan-Meier method and compared with Log-rank test. Overall survival (OS) was compared with age and sex-matched general Chinese population using expected survival and standardized mortality ratio (SMR). Cox stepwise regression model was used for multivariate analysis. Results: The 5-year OS and progression-free survival (PFS) were 87.2% and 77.2%. The SMR was 3.59 (P<0.001) at 1 year after treatment, whereas it was 1.50 at 4 years after treatment, without significant difference between ENKTCL group and country-matched general population (P=0.146). Compared with RT alone, CMT did not result in significantly superior 5-year OS (87.0% vs 87.4%, P=0.961) or PFS (76.1% vs 80.7%, P=0.129). Local failure (11.5%, 64/557) and distant failure (10.8%, 60/557) were the main failure modes, while regional failure was rare (2.9%, 16/557). The 5-year locoregional control rate (LRC) was 87.2% for the whole group, with 89.5% for ≥50 Gy versus 73.7% for <50 Gy (P<0.001). Radiotherapy dose was an independent factor affecting LRC(P<0.05). Conclusions: Radiotherapy achieves a favorable prognosis in patients with low-risk early-stage ENKTCL. The incidence of either locoregional or distant failure is low. Radiation dose still is an important prognostic factor for LRC.

[Correlation between aspiration and long-term survival of inpatients with chronic obstructive pulmonary disease]

Objective: To retrospectively analyze the high risk factors of death in patients with chronic obstructive pulmonary disease (COPD) and to explore the influence of aspiration on the long-term survival rate of COPD patients. Methods: A retrospective analysis of clinical data of inpatients, who were admitted to the First Affiliated Hospital of Guangzhou Medical University from April 2012 to December 2013 due to COPD exacerbations and had radionuclide aspiration test, was conducted. Meanwhile, we phoned the patients' family members, whose phone numbers were recorded in the electronic patient record system, to follow up the patients' survival status, and learn the causes of death from their death records if patients died during follow-up period. Inquired the resident administration patients belonging to according to their original address to get patient's current contact information if changed. Besides, if family members of patients failed to provide death record, we should look up information concerned from the medical records room of the hospital where they died. Results: The follow-up for the last patient was performed on February 20, 2017.The time span of this study is 58 months, starting from the radionuclide aspiration test for the first patient and ending with the follow-up for the last patient. 16 of the 53 patients(16/53, 30.2%)were tested positive whose average age was slightly higher than patients without aspiration (76.0±6.8 vs 70.9±9.9), but there was no significant difference between them(P=0.064). The aspiration rates among patients over and under the age of seventy were 14/35 and 2/18 respectively, and there was a significant difference between them(P = 0.03). Compared to the aspiration-negative patients, the aspiration-positive patients had higher incidence rate of pneumonia in COPD exacerbations (11/16 vs 9/37, χ²= 9.383, P = 0.002).The major cause of death in the patients with and without aspiration were respectively severe pneumonia and pulmonary encephalopathy(P<0.05 in both cases).Among COPD patients who took radionuclide aspiration test, the median survival time of the patients with and without aspiration were about 3 and 5 years respectively. The high-risk factors influencing long-term survival of the COPD patients with aspiration included ICU-involved medical history and accompanying pneumonia. Conclusions: The incidence rate of aspiration is relatively high in COPD patients over 70 years old. Compared to COPD patients without aspiration, COPD patients with aspiration have higher incidence rate of pneumonia and shorter median survival time. ICU-involved medical history and severe pneumonia are the two high-risk factors influencing long-term survival of COPD patients with aspiration.To improve the survival time of COPD patients with aspiration, we need to attach importance to the prevention and treatment of aspiration.

[Screening and analysis of Treponema pallidum specific antibody among childbearing age people in rural areas of Yunnan province, 2013-2017]

Objective: To determine the prevalence, epidemiological characteristics, and related factors of syphilis infection among rural childbearing age people to promote medical interventions on pre-pregnancy aristogenesis and syphilis infection in Yunnan province. Methods: The subjects in this study were 18-49-year-old rural couples of childbearing age from the National Free Preconception Health Examination Project in Yunnan province during 2013-2017. The descriptive study was carried out to determine the positive rate of Treponema pallidum specific antibody (TPsAb) and related sociodemographic characteristics. Results: The overall positive rate of TPsAb was 0.38% (8 204/2 160 455) in 2 160 455 rural childbearing age people in Yunnan. The positive rate of TPsAb was 0.39% (4 019/1 040 981) in men,higher than that in women (0.37%,4 185/1 119 474). The positive rate of TPsAb was highest in the age group 45-49 years (0.70%,158/22 511). The positive rate of TP antibody in the minority ethnic groups and Han ethnic groups appeared the same (0.38%). However,the highest positive rate of TPsAb was 0.77% (461/60 153) in Hani ethnic group among all the 17 minority ethnic groups. People with education level of primary education had the highest anti-TP positive rate (0.54%,2 327/431 275). The positive rate of TPsAb appeared the highest in Zhaotong (0.73%, 2 049/281 614) area among all the 16 prefectures of the province. The positive rate of TPsAb in the population from the impoverished regions (0.50%,2 963/590 039) was higher than in other disadvantaged areas (0.34%, 3 115/929 368) or areas with average income (0.33%,2 126/641 048). Significant differences appeared in the positive rate of TPsAb among populations of different ages, ethnic, education level, and economic level groups (trend χ² test, P<0.001). Conclusions: The positive rate of TP antibody in rural childbearing age people in Yunnan was related to multi factors,including sex,age,ethnic group,education level,area, residence, and local economic situation. The positive rate of TPsAb was higher in men than in women. And people with elder age, lower education level, being Hani or Lahu ethnic group, and Zhaotong areas had higher TPsAb positive rates and higher syphilis infection risk.

Ultrafast X-Ray Diffraction Visualization of B1-B2 Phase Transition in KCl under Shock Compression

The classical B1(NaCl)↔B2(CsCl) transitions have been considered as a model for general structural phase transformations, and resolving corresponding phase transition mechanisms under high strain rate shock compression is critical to a fundamental understanding of phase transition dynamics. Here, we use subnanosecond synchrotron x-ray diffraction to visualize the lattice response of single-crystal KCl to planar shock compression. Complete B1-B2 orientation relations are revealed for KCl under shock compression along ⟨100⟩_{B1} and ⟨110⟩_{B1}; the orientation relations and transition mechanisms are anisotropic and can be described with the standard and modified Watanabe-Tokonami-Morimoto model, respectively, both involving interlayer sliding and intralayer ion rearrangement. The current study also establishes a paradigm for investigating solid-solid phase transitions under dynamic extremes with ultrafast synchrotron x-ray diffraction.

[Formation of study population for causal inference]

Epidemiological analysis describes and compares the characteristics of a certain number of people to make causal inferences. The formation of the study population is always the first step. In this paper, we first define the concepts of cross-sections at both individual level and population level and introduce the three assumptions needed in the measurements in observational studies, i. e. the true values of the attributes are stable with time, the attribute variables are independent and the individuals are independent during the measuring process. We also determine that the causal inference research should be unified based on the time of the occurrence or beginning of a postulated cause, or exposure, should be in. Then, based on the dual roles of the population cross-section with causal thinking, we propose that research designs can be classified into two types with different characteristics: history reconstruction research and future exploration research. Finally, we briefly analyze the research design framework and the relationship between estimated effects and different designs. The discussion of the formation of a study population from the perspective of causal thinking can make a foundation for the classification of causal inference research design with appropriate effect parameters, which needs to be further studied.

Association of improved overall survival with decreased distant metastasis following asparaginase-based chemotherapy and radiotherapy for intermediate- and high-risk early-stage extranodal nasal-type NK/T-cell lymphoma: a CLCG study

BACKGROUND

This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based chemotherapy combined with radiotherapy in a real-world cohort of patients with early-stage extranodal nasal-type natural killer/T-cell lymphoma (ENKTCL).

PATIENTS AND METHODS

We identified 376 patients who received combined radiotherapy with either ASP-based (ASP, platinum, and gemcitabine; n = 286) or non-ASP-based (platinum and gemcitabine; n = 90) regimens. The patients were stratified into low-, intermediate-, and high-risk groups using the early stage-adjusted nomogram-revised risk index. Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses.

RESULTS

ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% versus 73.2%, P = 0.021) and DMFS (84.4% versus 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients in the setting of radiotherapy. Moreover, ASP-based regimens decreased DM, with a 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based chemotherapy and radiotherapy remained consistent after adjusting the confounding variables using IPTW and multivariate analyses; additional sensitivity analyses confirmed these results.

CONCLUSIONS

The findings provided support for ASP-based chemotherapy and radiotherapy as a first-line treatment strategy for intermediate- and high-risk early-stage ENKTCL.

Toroidal soft x-ray array on the EXL-50 spherical tokamak

A toroidal soft x-ray array system for spectrum and intensity measurements on the EXL-50 spherical tokamak is described. Silicon drift detectors and digital multichannel analyzers are adopted for all 21 channels of the array, and an average energy resolution of 147 eV at 5.89 keV has been achieved at count rates over 500 kcps. In total, 20 channels of the array are symmetrically observed in both co- and counter-current directions on the EXL-50 mid-plane with a spatial resolution of around 10 cm, and the remaining one serves as a background reference channel. Tungsten emissions from tungsten coating of the limiters on the central post are observed. The influence of hard x rays on measured soft x-ray spectra and system operation is discussed.

[Study on the hospitalization cost and its influencing factors of imported malaria patients in Guangxi Zhuang Autonomous Region and Yunnan Province]

OBJECTIVE

To analyze the hospitalization cost and its influencing factors of imported malaria patients in Guangxi Zhuang Autonomous Region and Yunnan Province, so as to provide insights into the evaluation of the economic burden due to imported malaria, and the guiding of malaria control and the rational allocation of medical resources.

METHODS

The data pertaining to the hospitalization costs of imported malaria patients admitted to Shanglin County People's Hospital in Guangxi Zhuang Autonomous Region during the period from January 1 through December 31, 2019, and Tengchong Municipal People's Hospital in Yunnan Province from January 1, 2015 to December 31, 2019, were collected, and the epidemiological data of these imported malaria patients were extracted from the Information Management System for Parasitic Diseases Control and Prevention, China. The composition of the hospitalization expenses was analyzed using a descriptive method. In addition, the factors affecting the hospitalization expenses of imported malaria patients were identified using a univariate analysis and a recursive system model.

RESULTS

A total of 206 imported malaria patients were included in this study, including 194 men (94.17%) and 12 women (5.83%). The mean length of hospital stay was 5.00 days per patient and the median hospitalization expenses were 2 813.07 Yuan per time, in which the expenses for laboratory examinations were the highest (45.31%, 1 274.62/2 813.07). Univariate analysis showed that hospital (z = 5.43, P < 0.01), type of malaria (χ² = 34.86, P < 0.01) and type of payment (χ² = 7.72, P < 0.05) were factors affecting the hospitalization expenses of imported malaria patients. Recursion system modeling revealed that the total effects on hospitalization expenses of imported malaria patients included length of hospital stay (0.78), selection of hospital (0.34), basic medical insurance for urban and rural residents (0.19), new rural cooperative medical care (0.17), Plasmodium falciparum malaria (0.15), gender (0.11) and P. vivax malaria (0.09).

CONCLUSIONS

The hospitalization expenses of imported malaria patients are affected by multiple factors in Guangxi Zhuang Autonomous Region and Yunnan Province, in which the length of hospital stay is the most predominant influencing factor. A reduction in the length of hospital stay is effective to decrease the hospitalization expenses of imported malaria patients.

Tangential hard x-ray diagnostic array on the EXL-50 spherical tokamak

A tangential hard x-ray (HXR) diagnostic on the newly constructed ENN XuanLong-50 (EXL-50) spherical tokamak for fast electron emission studies is presented. The HXR detection system consists of a symmetrical CdZnTe semiconductor detector array with a spectral sensitivity range of 20-300 keV. 25 channels have been designed on the 270° horizontal vacuum port with 12 sight lines to observe the forward emission, 12 sight lines to observe the backward emission of fast electrons, and 1 for viewing the central. Currently, ten channels have been in operation in the EXL-50 experiments. The systems are designed to measure the x-ray spectra for the estimation of fast electron temperature and electron velocity distribution in the EXL-50 experiment, which will be useful for understanding the dynamics of fast electrons generated by electron cyclotron resonance heating, for plasma instability and transport studies and for the analysis of plasma heating efficiency.

[Analysis on antimicrobial sensitivity of Neisseria meningitidis in China from 2005 to 2019]

Objective: To analyze the antimicrobial resistance characteristics of 538 Neisseria meningitidis isolated from 2005 to 2019 in China. Method: Total of 538 Neisseria meningitidis strains collected from 30 provinces in China from 2005 to 2019. Antimicrobial susceptibility test were performed based on the standards of clinical and laboratory standardization association (CLSI) including 11 recommended antibiotics. Gradient diffusion method was used to detect the antibiotic sensitivity of Neisseria meningitidis. Results: All 538 strains were sensitive to azithromycin, meropenem, chloramphenicol, rifampicin and ceftriaxone. As to other six antibiotics, the antibiotics sensitivity rates were cefotaxime (97.4%, 524 strains), ampicillin (87.7%, 472 strains), penicillin (84.8%, 456 strains), minocycline (95.2%, 512 strains), ciprofloxacin (24.9%, 134 strains) and trimethoprim/sulfamethoxazole (11.2%, 60 strains) respectively. Conclusions: Neisseria meningitidis isolated from 2005-2019 in China were all sensitive to azithromycin, meropenem, chloramphenicol, rifampicin and ceftriaxone. It should highlight Neisseria meningitidis resistant to cefotaxime, ampicillin and penicillin. Ciprofloxacin and sulfamethoxazole are not recommended as the priority choice for clinical treatment and prophylactic medication.

[The efficacy of hemostatic powder for chronic rhinosinusitis in endoscopic sinus surgery: a prospective, randomised, controlled and single blinded clinical trial]

Objective: To study the efficacy and patient comfort of absorbable hemostatic powder after endoscopic sinus surgery (ESS). Methods: A total of 21 (17 males, 4 females) patients with an average age of 42(ranging from 18 to 65) underwent bilateral ESS for chronic rhinosinusitis(CRS) in Beijing Tongren Hospital, Capital Medical University between October 2015 and July 2019 were enrolled to compare the effect of absorbable hemostasis powder with Nasopore using an intrapatient control design. A randomized controlled trial was conducted in the left and right nasal cavities of the same patient. If hemostatic powder was applied in the experiment nasal cavity, the Nasopore was applied in the control nasal cavity. The mean preoperative sinus computed tomography (CT) score was 6.25. All patients competed for symptom diaries using a visual analog scale (VAS, score out of 10) at baseline, through 1, 7, 14 and 30 days. Outcomes including bleeding, facial pain, nasal obstruction, nasal discharges using VAS were recorded separately for both sides. Postoperative endoscopic scores were also investigated. SPSS 22 and Graphpad prism 8.0 statistical softwares were used for the analysis. Paired t-test or nonparametric test was used between the test side and the control side. The difference was statistically significant (P<0.05). Results: The bleeding score and total nasal symptom VAS scores at postoperative days (POD) 1, 7, 14 and 30 were not significantly different(t=1.341, 0.552, 0.631, 0.158, all P>0.05;t=0.944, 1.471, 1.612, 2.251, all P>0.05). There was no significant difference between absorbable hemostasis powder and Nasopore side on POD 1, 7, 14 and 30 in terms of each nasal symptom VAS scores(all P>0.05). On POD 1, 7 and 14, the packing material degeneration scores of the absorbable hemostasis powder side were significantly lower than those of the Nasopore side [(1.33±0.21)vs(2.00±0.00),(0.38±0.18) vs (1.95±0.22), 0 vs (1.80±0.13), all P<0.01]. There were significant differences between absorbable hemostasis powder and Nasopore side on POD 1, 7, 14 and 30 in terms of endoscopic scores (edema, crusting, discharges, scar, polyps and material degeneration, t=3.07, 7.00, 6.41, 2.69, all P<0.05). Conclusions: The absorbable hemostasis powder and Nasopore has similar postoperative hemostasis effect. The absorbable hemostasis powder is rapidly cleared and without negative effects on mucosal wound healing 14 days postoperatively.