Objective Exploring genetic differences among geographic strains of Anopheles sinensis in China. Methods Based on the mitochondrial cytochrome oxidase subunit I(COⅠ )and ribosomal the second internal transcribed spacer(ITS2), genetic distance analyses were conducted on An. sinensis samples collected nationwide. Results Genetic differentiation was observed within An. sinensis geographic strains, primarily reflected in the genetic distances of COⅠ sequences, with some distances between samples exceeding those between closely related species. However, ITS2 sequences showed relatively low levels of differentiation within geographic strains. No significant separation was observed, and gene exchange exhibited a random pattern among geographic strains. Conclusions Significant differences in genetic distance were observed among An. sinensis samples, along with evidence of interspecific continuity among sibling species. For the identification of closely related species using wild-collected Anopheles mosquitoes samples, reliance solely on commonly used barcodes such as COⅠ and ITS2 may be insufficient. Additional molecular markers, including COⅡ and D3 gene fragments, should also be considered. Caution should be exercised when using COⅠ genes to identify cryptic species, especially within Anopheles mosquitoes.

Objective:To describe the body mass index (BMI) level and long-term trends of Chinese older adults aged 65 and above.Methods:Older adults aged 65 and above from six waves (2002-2018) of the China Longitudinal Healthy Longevity Survey were selected as the study population. Multiple cross-sectional design with six survey waves conducted in 2002, 2005, 2008, 2011, 2014, and 2018 was adopted, enrolling 15 647, 15 358, 15 622, 9 166, 6 302, and 12 417 participants, respectively. Additionally, a total of 13, 755 participants were included in the cohort study design. Relevant information was collected through questionnaires and physical examinations. The χ2 trend test was used to compare the changes in the rates of underweight and overweight/obesity over the years, and the linear mixed-e?ects model (LMM) was used to fit trajectory curves of BMI changes with advancing age in older adults. Results:The baseline ages of the participants included in 2002, 2005, 2008, 2011, 2014, and 2018 were (85.16±11.26), (84.23±11.83), (84.99±12.16), (81.10±11.86), (78.89±11.30), and (83.08±12.42) years, respectively, with a relatively high proportion of females and rural residents. In the cohort study, the 13 755 participants had a median ( Q1, Q3) follow-up time of 6.5 (5.2, 10.0) years, with a cumulative follow-up duration of 109 041 person-years. In each wave, males had higher BMI than females, urban residents had higher BMI than rural residents, and BMI gradually decreased with increasing age (all P<0.001). The mean BMI of older adults in China increased from (19.37±3.80) kg/m2 in 2002 to (22.04±4.01) kg/m2 in 2018 ( P<0.001). Across all survey years, the prevalence of underweight was consistently higher in women than in men and in rural areas than in urban areas, with an upward trend as age increased (all P<0.001). In 2018, the underweight rates in the 65-79, 80-89, 90-99, and ≥100-year-old age groups were 8.0%, 16.7%, 26.2%, and 35.5%, respectively. Meanwhile, the prevalence of overweight/obesity was higher in men than in women and in urban areas than in rural areas, showing a declining trend with advancing age (all P<0.001). The prevalence of underweight among the older adults decreased significantly from 45.2% in 2002 to 18.9% in 2018 ( P<0.001), while the prevalence of overweight/obesity increased from 11.0% in 1998 to 29.6% in 2018 ( P<0.001). The trajectory curves fitted by the LMM model showed that individuals born in later decades had higher BMI levels at the same age compared to earlier cohorts. Conclusion:From 2002 to 2018, the BMI level among Chinese older adults showed an increasing trend. The prevalence of underweight showed a declining trend, while the rates of obesity and overweight increased. However, the underweight rate remained notably high among the oldest old.

This study was aimed at evaluating the characteristics of H9N2 subtype avian influenza viruses(AIVs)origina-ting from wild birds in major wetlands in Fujian.Five H9N2 subtype AIVs isolated from fecal samples from wild birds in wet-lands of the Minjiang River,Jiulong River,Sandu Bay,Xinghua Bay,and Quanzhou Bay in Fujian were sequenced.Sequence a-nalysis of the HA genes of the five H9N2 subtype AIVs indicated that the five isolates shared 89.8％-99.4％nucleotide se-quence identity.All five isolates belonged to the same h9.4.2.5c evolutionary branch.The cleavage site motifs of HA were all PSRSSR ↓ GLF,thus indicating molecular characteristics of AIVs with low pathogenicity.The HA proteins of the viruses orig-inating from wild birds bore eight identical potential glycosylation sites,among which the glycosylation site at position 313 was located near the HA protein cleavage site.The 226th amino acid of HA in the receptor binding site was leucine in each virus,thus indicating that HAs of the five H9N2 subtype AIVs had mammalian sialic acid α-2,6 receptor binding affinity.In conclu-sion,the five H9N2 subtype AIVs originating from wild birds in Fujian had low pathogenicity,and the HAs had mammalian sialic acid α-2,6 receptor binding affinity.

Objective:To describe the body mass index (BMI) level and long-term trends of Chinese older adults aged 65 and above.Methods:Older adults aged 65 and above from six waves (2002-2018) of the China Longitudinal Healthy Longevity Survey were selected as the study population. Multiple cross-sectional design with six survey waves conducted in 2002, 2005, 2008, 2011, 2014, and 2018 was adopted, enrolling 15 647, 15 358, 15 622, 9 166, 6 302, and 12 417 participants, respectively. Additionally, a total of 13, 755 participants were included in the cohort study design. Relevant information was collected through questionnaires and physical examinations. The χ2 trend test was used to compare the changes in the rates of underweight and overweight/obesity over the years, and the linear mixed-e?ects model (LMM) was used to fit trajectory curves of BMI changes with advancing age in older adults. Results:The baseline ages of the participants included in 2002, 2005, 2008, 2011, 2014, and 2018 were (85.16±11.26), (84.23±11.83), (84.99±12.16), (81.10±11.86), (78.89±11.30), and (83.08±12.42) years, respectively, with a relatively high proportion of females and rural residents. In the cohort study, the 13 755 participants had a median ( Q1, Q3) follow-up time of 6.5 (5.2, 10.0) years, with a cumulative follow-up duration of 109 041 person-years. In each wave, males had higher BMI than females, urban residents had higher BMI than rural residents, and BMI gradually decreased with increasing age (all P<0.001). The mean BMI of older adults in China increased from (19.37±3.80) kg/m2 in 2002 to (22.04±4.01) kg/m2 in 2018 ( P<0.001). Across all survey years, the prevalence of underweight was consistently higher in women than in men and in rural areas than in urban areas, with an upward trend as age increased (all P<0.001). In 2018, the underweight rates in the 65-79, 80-89, 90-99, and ≥100-year-old age groups were 8.0%, 16.7%, 26.2%, and 35.5%, respectively. Meanwhile, the prevalence of overweight/obesity was higher in men than in women and in urban areas than in rural areas, showing a declining trend with advancing age (all P<0.001). The prevalence of underweight among the older adults decreased significantly from 45.2% in 2002 to 18.9% in 2018 ( P<0.001), while the prevalence of overweight/obesity increased from 11.0% in 1998 to 29.6% in 2018 ( P<0.001). The trajectory curves fitted by the LMM model showed that individuals born in later decades had higher BMI levels at the same age compared to earlier cohorts. Conclusion:From 2002 to 2018, the BMI level among Chinese older adults showed an increasing trend. The prevalence of underweight showed a declining trend, while the rates of obesity and overweight increased. However, the underweight rate remained notably high among the oldest old.

This study was aimed at evaluating the characteristics of H9N2 subtype avian influenza viruses(AIVs)origina-ting from wild birds in major wetlands in Fujian.Five H9N2 subtype AIVs isolated from fecal samples from wild birds in wet-lands of the Minjiang River,Jiulong River,Sandu Bay,Xinghua Bay,and Quanzhou Bay in Fujian were sequenced.Sequence a-nalysis of the HA genes of the five H9N2 subtype AIVs indicated that the five isolates shared 89.8％-99.4％nucleotide se-quence identity.All five isolates belonged to the same h9.4.2.5c evolutionary branch.The cleavage site motifs of HA were all PSRSSR ↓ GLF,thus indicating molecular characteristics of AIVs with low pathogenicity.The HA proteins of the viruses orig-inating from wild birds bore eight identical potential glycosylation sites,among which the glycosylation site at position 313 was located near the HA protein cleavage site.The 226th amino acid of HA in the receptor binding site was leucine in each virus,thus indicating that HAs of the five H9N2 subtype AIVs had mammalian sialic acid α-2,6 receptor binding affinity.In conclu-sion,the five H9N2 subtype AIVs originating from wild birds in Fujian had low pathogenicity,and the HAs had mammalian sialic acid α-2,6 receptor binding affinity.

Objective Spotted fever group rickettsiae(SFGR)are globally prevalent obligate intracellular bacteria that have the potential to cause severe and fatal human diseases. A study to investigate the species and genetic characteristics of SFGR was conducted in 2023 in the Ningxia region of northwestern China. Methods Tick samples were collected from Ningxia, identified, and used to isolate SFGR. The isolated strain was identified as Rickettsia raoultii through morphological observation, multi-locus sequence typing(MLST), and phylogenetic analysis. Then, it was subjected to whole-genome sequencing using next-generation technology, which revealed it to be a TIGMIC strain. Results The TIGMIC strain was demonstrated to exhibit a capacity for growth in mammalian cell lines. The complete genome sequence of the TIGMIC strain was assembled into a circular chromosome, which exhibited a length of 1 312 176 bp and comprised 1 488 genes. Functional annotation revealed that the main key genes of the TIGMIC strain were primarily associated with biosynthesis, nutrient metabolism, and cell membrane biogenesis. Apart from the rickA gene, most typical rickettsial virulence genes of the TIGMIC strain were relatively conserved. Conclusions These findings will help identify SFGR, provide etiological evidence for spotted fever in Ningxia, and emphasize the need for enhanced surveillance to prevent the spread of SFGR.

Aim To investigate the effect of polyphyl-lin Ⅱ(PP Ⅱ)on autophagy of osteosarcoma(OS)cells and its related molecular mechanism.Methods U2OS and HOS cells were cultured in vitro and treated with different concentrations of PP Ⅱ(5,10,15,20 μmol·L-1)for 24 h.The changes of acid vesicles were detected by AO staining,the autophagosomes was ob-served by transmission electron microscopy,the ex-pressions of LC3B-Ⅱ/LC3B-Ⅰ,p62,caspase-3,cleaved caspase-3 were detected by Western blot,the intracellular reactive oxygen species(ROS)was detec-ted by DCFH-DA fluorescence probe,cell viability was detected by CCK-8,cell apoptosis rate was detected by Annexin V-FITC/PⅠ staining.Results PP Ⅱ signifi-cantly increased the number of acidic vesicles(P＜0.05,P＜0.01)and autophagosomes.PP Ⅱ signifi-cantly up-regulated the ratio of LC3B-Ⅱ/LC3B-Ⅰ,and down-regulated the expression level of p62 protein in a concentration-and time-dependent manner(P＜0.05,P＜0.01).PP Ⅱ significantly increased intra-cellular ROS levels(P＜0.01).Autophagy inhibitor 3-MA and CQ could reverse the regulation of cell via-bility,autophagy and apoptosis related proteins by PP Ⅱ in U2OS cells,endoplasmic reticulum stress inhibi-tor 4-PBA could also reverse the regulation of autoph-agy related proteins by PP Ⅱ in U2OS cells.Conclu-sion PP Ⅱ promotes OS cell autophagy by mediating ROS and endoplasmic reticulum stress.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To assess the effectiveness and safety of prone positioning in the treatment of neonatal respiratory distress syndrome(NRDS)using invasive respiratory support.Methods A prospective study was conducted from June 2020 to September 2023 at Suining County People's Hospital,involving 77 preterm infants with gestational ages less than 35 weeks requiring invasive respiratory support for NRDS.The infants were randomly divided into a supine group(37 infants)and a prone group(40 infants).Infants in the prone group were ventilated in the prone position for 6 hours followed by 2 hours in the supine position,continuing in this cycle until weaning from the ventilator.The effectiveness and safety of the two approaches were compared.Results At 6 hours after enrollment,the prone group showed lower arterial blood carbon dioxide levels,inspired oxygen concentration,oxygenation index,rates of tracheal intubation bacterial colonization,and Neonatal Pain,Agitation and Sedation Scale scores compared to the supine group(P<0.05).There were no significant differences between the groups in terms of pH,arterial oxygen pressure,positive end-expiratory pressure,duration of mechanical ventilation,accidental extubation,ventilator-associated pneumonia,air leak syndrome,skin pressure sores,feeding intolerance,and grades II-IV intraventricular hemorrhage(P>0.05).Conclusions Compared to supine positioning,prone ventilation effectively improves oxygenation,increases comfort,and reduces tracheal intubation bacterial colonization in neonates requiring mechanical ventilation for NRDS,without significantly increasing adverse reactions.

Objective To analyze the risk factors of gastrointestinal bleeding in patients with type A aortic dissection(TAAD)after Sun's operation.Methods The clinical data of 87 patients who underwent TAAD Sun's operation in our hospital from March 2021 to June 2022 were retrospectively analyzed.They were divided into the bleeding group and the non-bleeding group according to whether there was gastrointestinal bleeding after operation.The clinical data of patients in the two groups was compared and analyzed.The binary Logistic regression analysis was used to analyze the risk factors of gastrointestinal bleeding.The clinical predictor of postoperative gastrointestinal bleeding was analyzed by receiver operating characteristic(ROC)curve.Results In this study,there were 40 cases of postoperative gastrointestinal bleeding(the bleeding group)and 47 cases of non-bleeding(the non-bleeding group).Compared with the non-bleeding group,the bleeding group had a shorter onset time,a higher proportion of patients with hypertension history,a higher preoperative creatinine abnormality rate,more intraoperative blood loss,longer postoperative mechanical ventilation time,higher postoperative infection rate,and higher poor prognosis rate,with statistically significant differences(P<0.05).There was no statistically significant difference in the gender,age,gastrointestinal diseases history,smoking history,preoperative platelets,preoperative international normalized ratio(INR),preoperative alanine aminotransferase(ALT),preoperative aspartate aminotransferase(AST),preoperative γ-glutamyl transpeptidase(GGT),preoperative dissection involving abdominal aorta,operation time,intraoperative cardiopulmonary bypass time,intraoperative circulatory arrest time,intraoperative aortic occlusion time or intraoperative blood transfusion rate.Logistic regression analysis showed that hypertension history(OR=2.468,95%CI:0.862 to 7.067,P=0.037),preoperative creatinine>105 μmol/L(OR=3.970,95%CI:1.352 to 11.659,P=0.011),long postoperative mechanical ventilation time(OR=1.015,95%CI:0.094 to 1.018,P=0.041)and postoperative infection(OR=3.435,95%CI:0.991 to 11.900,P=0.012)were the independent risk factors for postoperative gastrointestinal bleeding in TAAD patients.ROC curve showed that the postoperative mechanical ventilation time exceeding 64 hours were the clinical predictor of postoperative gastrointestinal bleeding in TAAD patients.Conclusion The prognosis of TAAD patients with postoperative gastrointestinal bleeding after Sun's operation is poor.Hypertension history,preoperative acute renal insufficiency,long postoperative mechanical ventilation time and postoperative infection are closely related to postoperative gastrointestinal bleeding in TAAD patients after operation,which should be paid more attention to,and corresponding evaluation,early identification and early intervention should be made to improve the prognosis of patients.