[Epidemiological characteristics and genotype trends of rotavirus diarrhea in China from 2009 to 2020].

Objective: To investigate the epidemiological characteristics and genotype trends of rotavirus infection among the population with diarrhea in China, from 2009 to 2020 and provide evidence for strategic surveillance and prevention. Methods: Surveillance data on diarrhea syndrome from 252 sentinel hospitals across 28 provinces (municipalities, autonomous regions) were obtained from the information management system of the Infectious Disease Surveillance Technology Platform of the National Science and Technology Major Project. Descriptive epidemiological methods were employed to analyze the distribution of rotavirus diarrhea cases in different climatic zones, populations, and times from 2009 to 2020, as well as the genotyping characteristics and changing trends of group A rotavirus diarrhea cases. Results: From 2009 to 2020, a total of 114 606 diarrhea cases were tested for rotavirus, and the positive rate was 19.1% (21 872/114 606); group A rotavirus was dominant (98.2%, 21 471/21 872). The positive rate of rotavirus was the highest in 2009 (36.9%, 2 436/6 604) and 2010 (30.6%, 5 130/16 790), fluctuated between 14.0% to 18.0% from 2011 to 2017, raised slightly in 2018 (20.3%, 2 211/10 900), and declined continuously in the following two years (15.5%, 2 262/14 611 and 9.5%, 470/4 963). The positive rate of males (20.2%, 13 660/67 471) was significantly higher than that of females (17.4%, 8 212/47 135). Children under five had the highest positive rate (28.4%, 18 261/64 300), more than four times that of adults. The positive rate peaked from December to February in the mediate temperate zone, warm temperate zone, and subtropical zone, while there were two peaks from November to January and May to June in the frigid zone of the plateau. The dominant genotype of group A rotavirus gradually changed from G3P[8] and G1P[8] to G9P[8] during 2009-2020. Conclusions: The overall rotavirus infection rate in China was on a downward trend. Meanwhile, significant variations of positive rates were observed in seasonal epidemics and different age groups from 2009 to 2020. Rotavirus diarrhea in children was still a prominent concern. Vaccination of rotavirus vaccine should be promoted, and the epidemiological characteristics and genotypes of rotavirus diarrhea should be continuously monitored.

[The association between portal vein thrombosis and rebleeding after non-urgent endoscopic treatment of esophagogastric varices].

Objective: To investigate the association between portal vein thrombosis and rebleeding after non-urgent endoscopic treatment of esophagogastric varices. Methods: The cirrhotic patients with esophagogastric varices diagnosed in the People's Hospital of Zhengzhou University from January 2017 to March 2023 were retrospectively collected. The patients were divided into thrombotic group and non-thrombotic group according to the presence or absence of portal vein thrombosis. The failure rate of endoscopic treatment and rebleeding rate in different periods were compared between the two groups. Receiver operating characteristic (ROC) curve was used to select the best cutoff value of gastric varicose diameter that affected total rebleeding during follow-up in both groups. The influencing factors of rebleeding within 12 and 36 months in both groups were analyzed, and the influencing factors of rebleeding within 36 months in thrombus group were further analyzed. Results: A total of 106 patients were enrolled, including 53 patients in the thrombotic group [male 37, female 16, aged 18-78 (54±13) years] and 53 patients in the non-thrombotic group [male 37, female 16, aged 27-83 (55±12) years]. The follow-up time of the two groups were (20±15) and (25±15) months, respectively. The total rebleeding rate in the thrombotic group was higher than that in the non-thrombotic group [30.2% (16/53) vs 13.2% (7/53), P˂0.05]. The rebleeding rates within 6, 12, 24 and 36 months in the thrombotic group were higher than those in the non-thrombotic group [18.9% (10/53) vs 5.7% (3/53), 18.9% (10/53) vs 5.7% (3/53), 28.3% (15/53) vs 9.4% (5/53), 30.2% (16/53) vs 11.3% (6/53), all P˂0.05]. The best cut-off value of the diameter of gastric varices that affects the total rebleeding in the two groups was 10.4 mm (10 mm was selected as the best cut-off value for the convenience of practical clinical application). Hemoglobin ˂ 85 g/L (HR=0.202, 95%CI: 0.043-0.953, P=0.043), 10 mm ˂ the diameter of GV ≤ 15 mm (HR=5.321, 95%CI: 1.161-24.390, P=0.031) and endoscopic variceal ligation combined with endoscopic tissue adhesive injection (EVL+ETAI) (HR=7.172, 95%CI: 1.910-26.930, P=0.004) were the risk factors for the first gastroesophageal variceal rebleeding within 12 months after non-urgent endoscopic treatment. EVL+ETAI (HR=3.811, 95%CI: 1.441-10.084, P=0.007) and portal vein thrombosis (HR=4.026, 95%CI: 1.483-10.932, P=0.006) were the risk factors for the first gastroesophageal variceal rebleeding within 36 months after non-urgent endoscopic treatment. The study found that, 10 mm ˂ the diameter of GV ≤ 15 mm (HR=7.503, 95%CI: 1.568-35.890, P=0.012) was the risk factor for rebleeding within 36 months in the thrombotic group. Conclusion: Portal vein thrombosis is a risk factor for rebleeding after non-urgent endoscopic treatment of esophagogastric varices.

[The ventilation efficacy and safety of new nasopharyngeal airway applied in left atrial appendage occlusion].

Objective: The present retrospective study aimed to analyses the ventilation efficacy and safety of new nasopharyngeal airway applied in left atrial appendage occlusion. Methods: A total of 37 advanced aged patients diagnosed with atrial fibrillation(>65 years)who underwent left atrial appendage occlusion (LAAO) in Xuanwu Hospital of Capital Medical University from March 2021 to March 2022 were enrolled in this study. All patients received supplemental oxygen by a new nasopharyngeal airway to ensure intraoperative ventilation. The primary outcome was the occurrence of hypoxemia. The secondary outcomes included the incidence of hypotension after anesthesia, the incidence of body movement during surgery, significant fluctuations of the vital signs such as mean arterial pressure (MAP), heart rate (HR), saturation of pulse oxygen (SpO2) and respiratory rate (RR) at different time points (T1: pre-operation; T2: at the time of placing nasopharyngeal airway; T3: at the time of placing transesophageal echocardiography(TEE); T4: at the time of TEE intraoperative exploration; T5: end of the surgery; T6: at the time of patient woke up), and the incidence of postoperative adverse events. Results: There were 24 males and 13 females with a mean age of (73.8±7.7) years. The incidence of hypoxemia was 16.2% (6/37), which could return to normal after simple treatment. The incidence of hypotension was 27.0% (10/37), occurred after anesthesia induction mainly.32.4% (12/37) of the patients experienced movements, but no adverse events led to surgical termination. MAP at different time points was significantly different (P=0.001), but other vital signs of HR, SpO2 and RR were not significantly different(all P>0.05), without serious hemodynamic fluctuations. The incidence of postoperative adverse cardiovascular events was 10.8% (4/37), and delirium was 2.7% (1/37). All patients successfully completed the surgery and were safely discharged from the hospital. Conclusion: The new nasopharyngeal airway can meet the requirements of airway management during left atrial appendage occlusion under intravenous anesthesia without serious adverse events.

[Efficacy and safety of bendamustine-rituximab combination therapy for newly diagnosed indolent B-cell non-Hodgkin's lymphoma and elderly mantle cell lymphoma: a multi-center prospective phase II clinical trial in China].

Objectives: This study aimed to assess the efficacy and safety of bendamustine in combination with rituximab (BR regimen) for the treatment of newly diagnosed indolent B-cell non-Hodgkin's lymphoma (B-iNHL) and elderly mantle cell lymphoma (eMCL) . Methods: From December 1, 2020 to September 10, 2022, a multi-center prospective study was conducted across ten Grade A tertiary hospitals in Shandong Province, China. The BR regimen was administered to evaluate its efficacy and safety in newly diagnosed B-iNHL and eMCL patients, and all completed at least four cycles of induction therapy. Results: The 72 enrolled patients with B-iNHL or MCL were aged 24-74 years, with a median age of 55 years. Eastern Cooperative Oncology Group (ECOG) performance status scores of 0-1 were observed in 76.4% of patients, while 23.6% had scores of 2. Disease distribution included follicular lymphoma (FL) (51.4% ), marginal zone lymphoma (MZL) (33.3% ), eMCL (11.1% ), and the unknown subtype (4.2% ). According to the Ann Arbor staging system, 16.7% and 65.3% of patients were diagnosed with stage Ⅲ and stage Ⅳ lymphomas, respectively. Following four cycles of BR induction therapy, the overall response rate was 98.6%, with a complete response (CR) rate of 83.3% and a partial response (PR) rate of 15.3%. Only one eMCL patient experienced disease progression during treatment, and only one FL patient experienced a relapse. Even when evaluated using CT alone, the CR rate was 63.9%, considering the differences between PET/CT and CT assessments. The median follow-up duration was 11 months (range: 4-22), with a PFS rate of 96.8% and an OS rate of 100.0%. The main hematologic adverse reactions included grade 3-4 leukopenia (27.8%, with febrile neutropenia observed in 8.3% of patients), grade 3-4 lymphopenia (23.6% ), grade 3-4 anemia (5.6% ), and grade 3-4 thrombocytopenia (4.2% ). The main non-hematologic adverse reactions such as fatigue, nausea/vomiting, rash, and infections occurred in less than 20.0% of patients. Conclusion: Within the scope of this clinical trial conducted in China, the BR regimen demonstrated efficacy and safety in treating newly diagnosed B-iNHL and eMCL patients.

[Risk factors of occult lymph node metastasis of levels â ¢ and â £ in papillary thyroid carcinoma].

Objective: To investigate the potential risk factors for occult lateral cervical lymph node metastasis (LNM) to levels Ⅲ and Ⅳ in patients with papillary thyroid carcinoma (PTC) and the necessity of super-selective lateral lymph node dissection for patients harboring these metastases. Methods: This prospective study included PTC patients who were operated by the same surgeon in the Department of Head and Neck Surgery of Cancer Hospital, Chinese Academy of Medical Sciences from October 2015 through October 2019. Preoperative ultrasound and enhanced Computer Tomography (CT) did not denote suspected enlarged lymph nodes in the lateral neck. All patients underwent lymph node dissection in levels Ⅲ and Ⅳ on the basis of original thyroid collar incision after LNM to level Ⅵ was confirmed by preoperative fine needlebiopsy or intraoperative frozen pathology. Results: Of all 143 patients, 74 (51.7%) had occult LNM in levels Ⅲ and Ⅳ confirmed by postoperative pathology. The average number of metastasized lymph nodes in levels Ⅲ and Ⅳ was 2.64±1.80, and that in level Ⅵ was 3.77±3.27. There was a significant linear positive correlation between the number of metastasized lymph nodes in level Ⅵ and that in levels Ⅲ and Ⅳ (r=0.341, P<0.001). That the metastasized lymph nodes in level Ⅵ equals three was the best predictor of occult lateral LNM to levels Ⅲ and Ⅳ. Univariate analysis showed that age <55 years, tumor size ≥2.0 cm, number of metastasized lymph nodes in level Ⅵ ≥3, and percentage of metastasized lymph nodes in the total number of dissected lymph nodes in level Ⅵ >50% were associated with occult LNM in levels Ⅲ and Ⅳ (P<0.05). Multivariate analysis showed that number of metastasized lymph nodes in level Ⅵ≥3 was an independent risk factor for occult LNM in levels Ⅲ and Ⅳ (P=0.006). Conclusions: Age, tumor size and LNM in level Ⅵ were associated with occult lateral LNM in PTC patients. Lymph node dissection in levels Ⅲ and Ⅳ could be considered for selective patients, since it will help to avoid secondary operation for residual tumor or recurrence resulted from insufficient treatment without increasing the incidence of complications or affecting patients' appearances.

[Mediating effect of self-efficacy on self-management ability and self-management behavior in patients with type 2 diabetes mellitus].

OBJECTIVE: To investigate the mechanism of self-efficacy between self-management ability and self-management behavior and its differences among patients with different disease courses through mediation tests. METHODS: In the study, 489 patients with type 2 diabetes who attended the endocrinology departments of four hospitals in Shanxi Province and Inner Mongolia Autonomous Region from July to September 2022 were enrolled as the study population. They were investigated by General Information Questionnaire, Diabetes Self-Management Scale, Chinese version of Diabetes Empowerment Simplified Scale, and Diabetes Self-Efficacy Scale. Mediation analyses were performed using the linear regression model, Sobel test, and Bootstrap test in the software Stata version 15.0 and divided the patients into different disease course groups for subgroup analysis according to whether the disease course was > 5 years. RESULTS: In this study, the score of self-management behavior in the patients with type 2 diabetes was 6.16±1.41, the score of self-management ability was 3.99±0.74, and the score of self-efficacy was 7.05±1.90. The results of the study showed that self-efficacy was positively correlated with self-management ability (r=0.33) as well as self-management behavior (r=0.47) in the patients with type 2 diabetes (P < 0.01). The mediating effect of self-efficacy accounted for 38.28% of the total effect of self-management ability on self-management behaviors and was higher in the behaviors of blood glucose monitoring (43.45%) and diet control (52.63%). The mediating effect of self-efficacy accounted for approximately 40.99% of the total effect for the patients with disease course ≤ 5 years, while for the patients with disease course > 5 years, the mediating effect accounted for 39.20% of the total effect. CONCLUSION: Self-efficacy enhanced the effect of self-management ability on the behavior of the patients with type 2 diabetes, and this positive effect was more significant for the patients with shorter disease course. Targeted health education should be carried out to enhance patients' self-efficacy and self-management ability according to their disease characteristics, to stimulate their inner action, to promote the development of their self-management behaviors, and to form a more stable and long-term mechanism for disease management.

[Analysis of prognosis and related factors in oldest-old patients with left-side or right-side colon cancer after hemicolectomy].

Objective: This study aimed to explore the difference of prognosis in oldest-old colon cancer patients between the left-side and right-side hemicolectomy. Methods: A total of 238 oldest-old (≥75 years old) colon cancer patients who received surgical treatment in Gastrointestinal Surgery Department of Beijing Hospital from December 2010 to December 2020 were retrospectively collected. They were divided into right-side hemicolectomy (RCC) group (130 cases) and left-side hemicolectomy (LCC) group (108 cases) by surgical methods. The difference in postoperative short-term complications and long-term prognosis was compared between the two groups, and the related factors of postoperative death was analyzed using multivariate Cox regression model. Results: The age of 238 oldest-old patients with colon cancer ranged from 75 to 93 years old (80.5±3.7). There were 128 males and 110 females. The ages of patients in the LCC group and RCC group were (80.4±3.7) and (80.6±3.7) years old (P=0.699), respectively. There was no significant difference in gender, body mass index (BMI) and co-existing chronic diseases between two groups (P>0.05). The proportion of the duration of surgery exceeding 170 min in the LCC group was significantly higher than that in the RCC group (56.5% vs 43.1%, P=0.039). The incidence of postoperative short-term complications in RCC group was slightly higher than LCC group (P>0.05), and there was no significant difference in overall survival (OS), tumor-specific survival (CSS) and disease-free survival (DFS) between two groups. However, the two groups had different prognostic risk factors, pathological Ⅳ stage (HR=28.970,95%CI:1.768-474.813,P=0.018), intraoperative bleeding (HR=2.297,95%CI:1.351-3.907,P=0.002) and cancer nodules (HR=2.044,95%CI:1.047-3.989,P=0.036) were independent prognostic risk factors in LCC group. Underweight (HR=0.428,95%CI:0.192-0.955,P=0.038), overweight(HR=0.316,95%CI:0.125-0.800,P=0.015),obesity (HR=0.211,95%CI:0.067-0.658,P=0.007), lymph node metastasis (HR=2.682,95%CI:1.497-4.807,P=0.001), tumor nodule (HR=2.507,95%CI:1.301-4.831,P=0.027) and postoperative length of stay of 9 days (HR=1.829,95%CI:1.070-3.128,P=0.006) were independent risk factors for poor prognosis in RCC group. Conclusions: The duration of surgery of oldest-old colon cancer patients in the LCC group was longer than that in the RCC group. However, there was no significant difference in the incidence of postoperative complications between the two groups. High pathological stage, more intraoperative bleeding and cancer nodules were independent prognostic risk factors in the LCC group. Abnormal BMI, lymph node metastasis, cancer nodules and postoperative length of stay were independent risk factors for poor prognosis in the RCC group.

[Performance of screening of contacts of COVID-19 cases in same flight].

Objective: To understand the performance of 2019-nCoV nucleic acid detection in screening of contacts of COVID-19 cases in same flights and provide evidence for the effective screening of persons at high risk for the infection in domestic flights. Methods: The information of passengers who took same domestic flights with COVID-19 cases in China from April 1, 2020 to April 30, 2022 were retrospectively collected,and χ2 test was used to analyze positive nucleic acid detection rates in the passengers in different times before the onsets of the index cases, in different seat rows and in epidemic periods of different 2019-nCoV variants. Results: During the study period, a total of 433 index cases were identified among 23 548 passengers in 370 flights. Subsequently, 72 positive cases of 2019-nCoV nucleic acid were detected in the passengers, in whom 57 were accompanying persons of the index cases. Further analysis of the another 15 passengers who tested positive for the nucleic acid showed that 86.67% of them had onsets or positive detections within 3 days after the diagnosis of the index cases, and the boarding times were all within 4 days before the onsets of the index cases. The positive detection rate in the passengers who seated in first three rows before and after the index cases was 0.15% (95%CI: 0.08%-0.27%), significantly higher than in the passengers in other rows (0.04%, 95%CI: 0.02%-0.10%, P=0.007),and there was no significant difference in the positive detection rate among the passengers in each of the 3 rows before and after the index cases (P=0.577). No significant differences were found in the positive detection rate in the passengers, except the accompanying persons, among the epidemics caused by different 2019-nCoV variants (P=0.565). During the Omicron epidemic period, all the positive detections in the passengers, except the accompanying persons, were within 3 days before the onset of the index cases. Conclusions: The screening test of 2019-nCoV nucleic acid can be conducted in the passengers took the same flights within 4 days before the onsets of the index cases on board. Passengers who seated within 3 rows from the index cases can considered as the close contacts at high risk for 2019-nCoV, for whom screening should be conducted first and special managements are needed. The passengers in other rows can be classified as general risk persons for screening and management.

[Latent period and incubation period with associated factors of COVID-19 caused by Omicron variant].

Objective: To estimate the latent period and incubation period of Omicron variant infections and analyze associated factors. Methods: From January 1 to June 30, 2022, 467 infections and 335 symptomatic infections in five local Omicron variant outbreaks in China were selected as the study subjects. The latent period and incubation period were estimated by using log-normal distribution and gamma distribution models, and the associated factors were analyzed by using the accelerated failure time model (AFT). Results: The median (Q1, Q3) age of 467 Omicron infections including 253 males (54.18%) was 26 (20, 39) years old. There were 132 asymptomatic infections (28.27%) and 335 (71.73%) symptomatic infections. The mean latent period of 467 Omicron infections was 2.65 (95%CI: 2.53-2.78) days, and 98% of infections were positive for nucleic acid test within 6.37 (95%CI: 5.86-6.82) days after infection. The mean incubation period of 335 symptomatic infections was 3.40 (95%CI: 3.25-3.57) days, and 97% of them developed clinical symptoms within 6.80 (95%CI: 6.34-7.22) days after infection. The results of the AFT model analysis showed that compared with the group aged 18-49 years old, the latent period [exp(ß)=1.36 (95%CI: 1.16-1.60), P<0.001] and incubation period [exp(ß)=1.24 (95%CI: 1.07-1.45), P=0.006] of infections aged 0-17 years old were prolonged. The latent period [exp(ß)=1.38 (95%CI: 1.17-1.63), P<0.001] and the incubation period [exp(ß)=1.26 (95%CI: 1.06-1.48), P=0.007] of infections aged 50 years old and above were also prolonged. Conclusion: The latent period and incubation period of most Omicron infections are within 7 days, and age may be a influencing factor of the latent period and incubation period.

[Clinical study on the classification of renal artery involvement and comparison of renal function and prognosis of Stanford type B aortic dissection after thoracic aortic endovascular repair].

Objective: To investigate the different types of renal artery involvement in Stanford type B aortic dissection (TBAD) and the comparison of clinical effecacy after thoracic endovascular aortic repair (TEVAR). Methods: This is a retrospective cohort study included 330 patients with TBAD and renal artery involvement treated with TEVAR from June 2002 to September 2021 in General Hospital of Northern Theater Command of the PLA. According to aortic CTA image, unilateral renal artery involvement conditions were divided into 5 types: the true lumen type (renal artery opening completely from the true lumen), false lumen type (renal artery opening completely from the false lumen), double lumen type (renal artery opening from the true and false double lumen), compression type (renal artery opening connected with the true lumen, but the renal artery opening was extremely squeezed by the inner membrane), open type (renal artery opening with intimal tear). There were seven types of bilateral renal artery involvement: true-true type (true lumen-true lumen type), true and false type (true lumen-false lumen type), true-double type (true lumen-double lumen type), true-opening type (true lumen-opening type), false-false type (false lumen-false lumen type), false-compression type (false lumen-compression type), double-double type (double lumen-double lumen type). The primary observation index of this study was the comparison of postoperative renal function and the incidence of clinical adverse events of different types of renal artery involvement. One-way ANOVA test, Kruskal-Wallis H test and paired sample rank sum test were used to compare postoperative renal function between different types of bilateral renal artery involvement. The Chi-square test or Fisher's exact probability test were used to compare the near and long term adverse events between different types of bilateral renal artery involvement. Kaplan-Meier method was used to compare the all-cause mortality of patients with severe renal functional injury and non-severe renal functional injury before surgery. Results: The average age of the patients included in this study was (53±11) years, including 276 males (83.6%) and 54 females (16.4%). There were statistical difference in the level of serum creatinine (preoperative:H=18.686, P=0.005, postoperative:H=18.101, P=0.006) and cystatin C (preoperative:H=17.566, P=0.007, postoperative:H=10.433, P=0.016), pre-and post-operative, between the seven groups of TBAD patients with different renal artery involvement types (P<0.05), and the false-false type group shown the worst kidney function. However, no statistically significant differences were shown when comparing their pre- and post-operative change values (P>0.05). The 30-day follow-up result showed that there were statistically significant differences in the incidence of postoperative acute kidney injury (χ2=15.623, P=0.007), aorta-related adverse events (χ2=15.523, P=0.010), and intraoperative endoleak (χ2=17.935, P=0.004) among the seven groups, and the false-false group was the highest (2/9, 5/9 and 5/9, respectively). In terms of long-term follow-up results, there were statistically significant differences in all-cause death (χ2=14.772, P=0.011) and non-aortic death (χ2=15.589,P=0.008) among the seven groups. Kaplan-Meier survival analysis showed that patients with worse pre-operative renal function showed higher long-term all cause death (17.7% vs. 4.8%, P=0.009). Conclusions: For TBAD patients with renal artery involvement, there were differences in renal function among different types, and TEVAR showed no significant effect on renal function in TBAD patients. The long-term all cause death was higher in patients with worse renal function pre-operative.

First report of Alternaria alternata causing leaf yellow spot on Heteropanax fragrans in China.

Heteropanax fragrans (Roxb.) Seem is a common garden landscape tree in China. In December 2020, a leaf disease on H. fragrans was observed in a 2 ha field in Zhanjiang (20.85° N, 109.28° E), Guangdong province, China. Early symptoms were small yellow spots on leaves. Later, the spots gradually expanded and turned into necrotic tissues with a clear yellow halo and a white center. The disease incidence on plants was 100%. Twenty diseased leaves were collected from the field. The margin of the diseased tissues was cut into 2 mm × 2 mm pieces, surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 and 60 s, respectively, and rinsed thrice with sterile water before isolation. The tissues were plated onto potato dextrose agar (PDA) medium and incubated at 28 ℃. After 2-day incubation, grayish fungal colonies appeared on the PDA, then pure cultures were produced by transferring hyphal tips to new PDA plates. Single-spore isolation method was used to recover pure cultures for three isolates (HFA-1, HFA-2, and HFA-3). The colonies first produced a light-grayish aerial mycelia, which turned dark grayish upon maturity. Conidiophores were branched. Conidia numbered from two to four in chains, were dark brown, ovoid, or ellipsoid and mostly beakless; had 1-4 transverse and 0-3 longitudinal septa; measured within 7.2-17.8 (average = 10.2) × 2.5-7.5 (average = 4.3) µm (n = 30). Molecular identification was performed using the colony polymerase chain reaction method with MightyAmp DNA Polymerase (Takara-Bio, Dalian, China) (Lu et al. 2012) to amplify the large subunit (LSU), internal transcribed spacer (ITS) region, translation elongation factor (TEF) , and Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) with NL1/LR3, ITS1/ITS4, EF-1α-F/EF-1α-R, and GDF1/GDR1 (Walther et al. 2013;Woudenberg et al. 2015; Nishikawa and Nakashima. 2020). Amplicons of the isolates were sequenced and submitted to GenBank (LSU, ON088978-ON088980; ITS, MW629797, ON417005 and ON417006; TEF, MW654167, ON497264,and ON497265;GAPDH, MW654166, ON497262,and ON497263). The obtained sequences were 100% identical with those of Alternaria alternata strain CBS 102600 upon BLAST analysis . The sequences were also concatenated for phylogenetic analysis by maximum likelihood. The isolates clustered with A. alternata (CBS 102600, CBS 102598, CBS 118814, CBS 918.96,CBS 106.24, CBS 119543, CBS 916.96). The fungus associated with leaf yellow spot on H. fragrans was thus identified as A. alternata. Pathogenicity tests were conducted in a greenhouse at 24 â„ƒ-30 â„ƒ with 80% relative humidity. Individual plants were grown in pots (n = 5, 1 month old). The unwounded leaflets were inoculated with 5 mm-diameter mycelial plugs of the isolates or agar plugs (as control). The test was performed thrice. Disease symptoms were found on the leaves after 7 days, whereas the controls remained healthy. The pathogen was re-isolated from infected leaves and phenotypically identical to the original isolates to fulfill Koch's postulates. To our knowledge, this report is the first one on A. alternata causing leaf yellow spot on H. fragrans. Thus, this work provides an important reference for the control of this disease in the future.

[Active surveillance for thyroid micro-malignant nodules].

Objective: To evaluate the effect of ultrasound diagnosis of thyroid micro-malignant nodules and accumulate practical experience for the management of active surveillance for them, so as to avoid overtreatment. Methods: A total of 949 patients who were diagnosed with thyroid malignant nodules using ultrasonography, with the nodules being less than 1 cm in size and without regional lymph node metastasis or distant metastasis, were included. They were treated by the same surgeon of the Department of Head and Neck Surgery, Cancer Hospital, Chinese Academy of Medical Sciences from February 2014 to December 2020. 112 patients chose immediate surgery. The rest patients were asked to accept ultrasound examination every 6 months to 1 year. Follow-up endpoints: tumor size growth of 3 mm, tumor volume increase greater than 50%, lymph node metastasis or distant metastasis. Results: The median follow-up time was 19 months. 713 patients underwent surveillance for more than 6 months. Of the 713 patients, 570 (79.9%) were women, with mean age at 43.5 years old. Tumor progression was observed in 47 (6.6%) patients with a cumulative incidence of 2.7% (1 year), 7.2% (2 years) and 9.5% (3 years). In multivariate analysis, patient age [HR=0.508, 95%CI: 0.275-0.939, P=0.031], lesion number [HR=2.945, 95%CI: 1.593-5.444, P=0.001] and tumor size [HR=2.245, 95%CI: 1.202-4.192, P=0.011] at the beginning of observation were independent risk factors for tumor progression in patients with minimal thyroid malignant nodules during follow-up. During a median (range) active surveillance of 19 (6-80) months, 74 patients chose surgery during the surveillance. Among the 186 patients who underwent surgery, only 3 patients were diagnosed with fibrotic nodules in pathology, while the rest were papillary thyroid carcinoma. The ultrasound accuracy reached 98.4%(183/186). Conclusions: Ultrasonography is an effective method of diagnosing malignant thyroid nodules. Thyroid micro-malignant nodules progress slowly. As a result, it is safe to observe them instead of taking immediate surgery. Patient age, lesion number and tumor size at the beginning of observation are independent risk factors for the tumor progression of malignant nodules.

[Clinical characteristics of Mycoplasma pneumoniae infection and factors associated with co-infections in children].

Objective: To describe the clinical characteristics of Mycoplasma pneumoniae infection and analyze the factors associated with co-infections with other pathogens in children, and provide evidence for improvement of community acquired pneumonia (CAP) prevention and control in children. Methods: Based on the surveillance of hospitalized acute respiratory infections cases conducted in Soochow University Affiliated Children's Hospital (SCH), the CAP cases aged <16 years hospitalized in SCH between 2018 and 2021 were screened. The pathogenic test results of the cases were obtained through the laboratory information system, and their basic information, underlying conditions, and clinical characteristics were collected using a standardized questionnaire. The differences in clinical characteristics between M. pneumoniae infection and bacterial or viral infection and the effect of the co-infection of M. pneumoniae with other pathogens on clinical severity in the cases were analyzed; logistic regression was used to analyze the factors associated with the co-infections with other pathogens. Results: A total of 8 274 hospitalized CAP cases met the inclusion criteria. Among them, 2 184 were positive for M. pneumoniae (26.4%). The M. pneumoniae positivity rate increased with age (P<0.001), and it was higher in girls (P<0.001) and in summer and autumn (P<0.001). There were statistically significant differences in the incidence of wheezing, shortness of breath, wheezing sounds and visible lamellar faint shadow on chest radiographs, as well as fever and hospitalization days among M. pneumoniae, bacterial, and viral infection cases (all P<0.05). In the cases aged <60 months years, co-infection cases had higher rates of wheezing, gurgling with sputum and stridor; and in the cases aged ≥60 months, co-infection cases had a higher rate of shortness of breath (all P<0.05). Multifactorial logistic regression analysis showed that being boys (aOR=1.38,95%CI:1.15-1.67), being aged <6 months (aOR=3.30,95%CI:2.25-4.89), 6-23 months (aOR=3.44,95%CI:2.63-4.51), 24-47 months (aOR=2.50,95%CI:1.90-3.30) and 48-71 months (aOR=1.77,95%CI:1.32-2.37), and history of respiratory infection within 3 months (aOR=1.28,95%CI:1.06-1.55) were factors associated with co-infections of M. pneumoniae with other pathogens. Conclusions: M. pneumoniae was the leading pathogen in children hospitalized due to CAP. M. pneumoniae infections could cause fever for longer days compared with bacterial or viral infections; M. pneumoniae was often co-detected with virus or bacteria. Being boys, being aged <72 months and history of respiratory infection within 3 months were associated factors for co-infections.

Pseudocercospora rhododendricola Causing Leaf dark Spot on Rhododendron pulchrum by the first phylogenetic analyses.

Rhododendron pulchrum Sweet is a famous ornamental flower in China. In December 2020, a leaf spot disease was observed on cv. Maojuan in Zhanjiang (21.17 N, 110.18 E), Guangdong, China. The spots were irregular and distributed on both sides of the main vein. They were dark to black, and their borders were obvious. The coalescence of the spots eventually led to leaf wilt. The disease incidence was 100% (n = 100, about 50 ha ). Thirty infected leaves were collected from the field, and the margin of the diseased tissues was cut into 2 mm × 2 mm pieces. Samples were surface disinfected with 75% ethanol and 2% sodium hypochlorite for 30 and 60 s, respectively. They were rinsed thrice with sterile water before isolation. The tissues were plated on potato dextrose agar (PDA) medium and incubated at 28 ℃. After 5 days, fungal colonies appeared on the PDA. Pure cultures were produced by transferring hyphal tips to new PDA plates. Three isolates (RSP-1, RSP-2, and RSP-3) were obtained and the colonies of isolates were preserved in glycerol (15%) at -80 °C deposited at the Museum of Guangdong Ocean University. The morphology of these three isolates was consistent, and their sequences showed 100% homology according to ITS, TEF1, and ACT analysis results. The colonies grew to approximately 5 cm in diameter after 10 days. They showed olive green with off-white aerial mycelia. Stromata and conidia were observed on leaf lesions. Stromata were olivaceous brown. Conidia were solitary, cylindrical to narrowly obclavate, mildly curved, obtuse to rounded at the apex, and 1- to 3-septate; they had dimensions of 20 to 60 × 2.0 to 3.0 µm (n = 30). These morphological characteristics were not different from the description of Pseudocercospora rhododendricola (J.M. Yen) Deighton (Liu et al. 1998). For molecular identification, the colony PCR method with MightyAmp DNA Polymerase (Takara-Bio, Dalian, China) (Lu et al. 2012) was used to amplify the internal transcribed spacer (ITS), translation elongation factor 1-α gene (TEF1), and actin (ACT) loci of the isolates using primer pairs ITS4/ITS5, EF1/EF2, and ACT-512F/ACT-783R, respectively (White et al., 1990; O'Donnell et al. 1997). The sequences of the isolate RSP-1 were deposited in the GenBank (ITS, MW629798; TEF1, MW654168; and ACT, MW654170). BLAST analysis showed that the sequences of P. rhododendricola were submitted to GenBank for the first time by the author of this paper. A phylogenetic tree was generated based on the concatenated data of ITS, TEF1, and ACT sequences from GenBank by the Maximum Likelihood method. The isolates were closest to Pseudocercospora sp. CPC 14711 (Crous et al., 2013). Phylogenetic and morphological analyses identified the isolates as P. rhododendricola. Pathogenicity tests were conducted in a greenhouse at 24 °C-30 â„ƒ with 80% relative humidity. Healthy cv. Maojuan were grown in pots. Unwounded leaflets were inoculated with 5 mm-diameter mycelial plugs of the isolates or agar plugs (as control) (5 leaflets per plant, 3 plants, 2-month-old plants). The test was performed thrice. Disease symptoms were found on the leaves after 2 weeks, whereas the control plants remained healthy. The fungus was re-isolated from the infected leaves and confirmed as the same isolates by morphological and ITS analyses. P. rhododendricola was the cause of leaf spot of Rhododendron sp. from Singapore (Liu et al., 1998). For the first time, this pathogen was identified by combining phylogenetic and morphological analyses. The sequences in this study would be used as the reference sequences for further studies.

[Contrastive analysis about the postoperative clinical characteristics of elderly patients with colorectal cancer in different age groups].

Objective: To explore the postoperative clinical characteristics of elderly patients with colorectal cancer at different ages. Methods: Retrospective analysis was performed on the clinical data of 720 elderly patients with Colorectal Cancer in Beijing Hospitals from January 2012 to December 2019. There were 411 males and 309 females with a median age of 74 years. We divided the patients into young-old, old-old, oldest-old colorectal cancer patient groups and used chi-square comparative analysis of different groups of patients with clinical disease characteristics. Results: The oldest-old colorectal cancer patients tended to have normal body mass index (BMI), and the site of the disease shifted to the right. The incidence of concomitant diseases such as heart disease and hypertension increases gradually with age, and the incidence of diabetes is highest in old-old colorectal cancer patients. The proportion of open surgery was higher in the oldest-old group, but the operation time was shorter than the other two groups. In addition, the incidence of postoperative complications in elderly patients with colorectal cancer gradually increases with age, especially cardiac complications and other complications such as pneumonia, deep venous thrombosis of lower limbs, urinary retention, urinary tract infection, renal failure, cerebral hemorrhage, cerebral infarction, and so on. Conclusions: The BMI of the oldest-old patients tended to be normal, and the site of the disease shifted to the right. The incidence of heart disease, hypertension, and other concomitant diseases and postoperative complications in elderly patients with colorectal cancer gradually increase with age. Thus, the choice of treatment should be more individualized for elderly patients with colorectal cancer, and more attention should be paid to perioperative management.

[Time distribution of positive nucleic acid detection in imported cases infected with SARS-CoV-2 in China].

Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q1, Q3) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8th -13th day after the entry.

[Effect of the acetabular cup positioning and leg length restoration after total hip arthroplasty using robotic-assisted surgery system].

Objective: To assess the improvement of the robotic-assisted total hip arthroplasty (rTHA) regarding the acetabular cup positioning and the leg length restoration. Methods: Clinical data of 246 patients undergoing primary unilateral THA from September 2019 to June 2021 in Peking University Third Hospital were retrospectively reviewed, including patients treated with rTHA (n=113) and conventional THA (cTHA) (n=133). Thirty-seven male patients along with 76 females were enrolled into the rTHA group with a mean age of (62±9) years. In comparison, the average age of cTHA group was (60±12) years with 59 males and 74 females. The postoperative inclination and anteversion of the acetabular cup and the rate of acetabular cup within the Lewinnek and Callanan "safe zone" were documented and analyzed. For the patient with normal or surgically restored contralateral hip, the leg length discrepancy was also measured and compared between the two groups. Results: The overall mean postoperative inclination and anteversion was 39.0°±5.5° and 14.1°±5.1°, respectively. No statistically significant difference was found between the rTHA and cTHA group regarding postoperative inclination (39.3°±2.9° vs 38.7°±7.0°, P=0.383) and anteversion (13.4°±4.3° vs 14.7°±5.6°, P=0.054). In rTHA group, 97.3%(110/113) of the cups were implanted within the Lewinnek"safe zone"(75.9%(101/133) in cTHA group) and 94.7%(107/113) were within the Callanan"safe zone"(66.2%(88/133) in cTHA group), and those were both higher in rTHA group (both P<0.01). There was no significant difference in postoperative leg length discrepancy between the two groups (P=0.445). Meanwhile, 29(23.0%) cases of cTHA group had leg length discrepancy more than 5 mm, and it was 9.7%(9/93) in rTHA group. Conclusion: It indicated the benefit of rTHA in acetabular cup positioning as well as the leg length restoration.

[Comparison of alignment and position of prosthesis between portable accelerometer-based navigation device and conventional instrumentation in total knee arthroplasty with valgus deformity].

Objective: To explore the differences of alignment and position of prosthesis between portable accelerometer-based navigation device (PAD) and conventional instrumentation (CI) in total knee arthroplasty (TKA) with valgus deformity. Methods: Patients with knee osteoarthritis and valgus deformity who underwent primary TKA in Peking University Third Hospital from January 2017 to December 2020 were enrolled in this retrospective study and were divided into PAD group and CI group according to the surgical instruments. Five male patients and 44 female patients were included with a mean age of (67.2±7.0) years. The differences in preoperative general data, preoperative and postoperative alignment between the two groups were studied. Results: A total of 49 patients (25 patients in the PAD group and 24 in the CI group) were enrolled in this study. There were no statistically significant differences in gender, age, height, weight, body mass index, surgical side, preoperative hip-knee-ankle (HKA) angle, preoperative HKA angle deviation, Keblish classification and Ranawat classification between the two groups (all P>0.05). There was no significant difference in the accuracy of postoperative HKA angle (2.0°±1.4° vs 3.0°±2.2°, P=0.082), coronal femoral component angle (CFCA) (1.5°±1.2° vs 2.1°±1.6°, P=0.144) and coronal tibial component angle (CTCA) (1.2°±0.8° vs 1.3°±1.0°, P=0.695) between the two groups; but the standard deviation of the above-mentioned three indices in PAD group were all smaller than those in CI group. The rate of outliers of postoperative HKA angle of the PAD group was smaller than that in the CI group (P<0.05), but there was no significant difference in the rate of outliers of CFCA and CTCA between the two groups (both P>0.05). Conclusion: TKA assisted by PAD can provide good alignment and prosthesis position in patients with valgus deformity, and it is superior to TKA with CI in terms of precision and rate of outliers of postoperative overall alignment of lower extremity.

[Investigation of incidence of acute respiratory infection and healthcare-seeking behavior in period of COVID-19 epidemic].

Objective: To analyze the incidence of acute respiratory infection (ARI) and related healthcare seeking behaviors in population in the period of COVID-19 epidemic in China. Methods: According to the province specific cumulative incidence rates of COVID-19 reported as of March 31, 2020, the low, medium and high-risk areas were classified. In these areas, a stratified two stage cluster random sampling method was used to select participants for face-to-face questionnaire surveys. Data on the incidence of ARI and related healthcare seeking behaviors in community residents during COVID-19 epidemic period were collected to calculate the attack rate of ARI and related healthcare seeking rate. Logistic regression method was used to explore the influencing factors for ARI incidence and healthcare seeking behavior. Results: A total of 34 857 community residents were surveyed, in whom 647 (1.9%) reported that they had ARI symptoms during the COVID-19 epidemic period, and 241 (37.2%) had healthcare seeking behaviors. In terms of the incidence of COVID-19-related ARI, in high-risk area, the risk of COVID-19-related ARI was 1.36 times (95%CI: 1.12-1.65) than that in low-risk area; among different age groups, the risk of COVID-19-related ARI in age groups 20-39 years, ≥60 years was 1.80 times (95%CI: 1.29-2.59) and 1.63 times (95%CI: 1.14-2.40) than that in age group 1-9 years; the risk of COVID-19-related ARI in people with underlying diseases was 1.53 times (95%CI: 1.23-1.89) than that in those without underlying diseases; the risk of COVID-19-related ARI in people with contacts with confirmed cases of COVID-19 and people with fever or respiratory symptoms was 1.53 times (95%CI: 1.01-2.27) and 6.60 times (95%CI: 5.05-8.53) than those in people without these contacts. The healthcare seeking rate in COVID-19-related ARI patients with exposures to those with fever or respiratory symptoms was 1.68 times (95%CI: 1.05-2.70) than that in such patients without the exposures. Conclusions: The attack rate of COVID-19-related ARI was affected by the local epidemic level of COVID-19, and in high-risk area, the attack rate of COVID-19-related ARI was also high. The healthcare seeking rate in patients with COVID-19-related ARI was low. Therefore, it is necessary to encourage the healthcare seeking in people with ARI in COVID-19 pandemic period.