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.

Hepatocellular carcinoma(HCC)is the most common type of primary liver cancer and the third leading cause of cancer-related deaths,and it is a serious threat to human health and has become a clinical problem that needs to be solved urgently.Extracellular vesicles(EV)are membrane vesicles containing multiple components and play an important role in the development and progression of HCC.This article summarizes the effect of EVs of different origins on HCC and analyzes the mechanism of action of EV on HCC,so as to provide new perspectives for the diagnosis and treatment of HCC.

Tumor necrosis factor-α(TNF-α)is involved in the regulation of multiple biological processes such as the proliferation,invasion,migration,and chemotherapy resistance of hepatocellular carcinoma(HCC)cells through TNF receptor-mediated signaling pathways.At the same time,TNF-α also plays a role in inducing the apoptosis of HCC cells.Some TNF-α inhibitors have been shown to inhibit the progression of HCC and prolong survival time.At present,the potential mechanism of action of TNF-α in HCC remains unclear,and exploration of the interaction between TNF-α and HCC can help to determine the potential therapeutic targets for HCC.This article summarizes the latest research advances in the mechanism of action of TNF-α in HCC and introduces the possibility of targeting TNF-α as a treatment method for HCC,in order to provide a theoretical basis for the prevention and treatment of liver cancer and drug research and development.

Objective To explore the independent risk factors that affect the overall survival(OS)of elderly patients with hepatocellular carcinoma(HCC,≥60 years old)and build a nomogram prediction model.Methods Clinical data of all elderly patients with HCC from the SEER database from 2005 to 2020 were downloaded from SEER database.In accordance with the inclusion and exclusion criteria,the screened patients were randomly assigned to a training group(70%)and a validation group(30%).The independent risk factors of elderly patients with HCC were determined by univariate and multivariate Cox regression analyses and further validated by Kaplan-Meier survival analysis.On the basis of the determined variables,nomograms were developed and verified to predict the OS of elderly patients with HCC at 6,12,and 24 months.The consistency index(C index),calibration curve,receiver's operating characteristic(ROC)curve,and area under curve(AUC)were used to evaluate the prediction efficiency and discrimination ability of the prediction model,and decision curve analysis(DCA)was used to evaluate the potential clinical application value of the nomogram.Results A total of 1134 elderly patients with HCC were included,with 793 in the training group and 341 in the validation group.Seven variables,including age,clinical grade,clinical stage,M stage,tumor size classification,and radiotherapy,were identified as independent prognostic factors of this population.The constructed nomogram shows excellent prediction performance,with C indices of 0.745 in the training group and 0.704 in the validation group.The AUC values of the training group at 6,12,and 24 months were 0.785,0.788,and 0.798,respectively,and those of the validation group were 0.780,0.725,and 0.607,respectively.The calibration curve shows good consistency from the predicted survival probability to the actual probability.The ROC curve and DCA show that the nomogram proposed in this study has good prediction ability.Conclusion Age,clinical grade,clinical stage,M stage,tumor size classification,and radiotherapy are important influencing factors for the survival of elderly patients with HCC.The prediction model of prognosis nomogram constructed in this study has good predictive value,and it can be used to predict the OS of elderly patients with HCC,which could be helpful for individualized survival assessment and clinical management of these patients.

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]