The Epidemiology of Pathogens in Community-Acquired Pneumonia Among Children in Southwest China Before, During and After COVID-19 Non-pharmaceutical Interventions: A Cross-Sectional Study.

OBJECTIVE: This study aimed to investigate the pathogen epidemiology of community-acquired pneumonia (CAP) among children in Southwest China before, during and after the COVID-19 non-pharmaceutical interventions (NPIs). METHODS: Pathogen data of hospitalised children with CAP, including multiple direct immunofluorescence test for seven viruses, bacterial culture and polymerase chain reaction (PCR) for Mycoplasma pneumoniae, were analysed across three phases: Phase I (pre-NPIs: 1 January 2019 to 31 December 2019), Phase II (NPI period: 1 January 2020 to 31 December 2020) and Phase III (post-NPIs: 1 January 2023 to 31 December 2023). RESULTS: A total of 7533 cases were enrolled, including 2444, 1642 and 3447 individuals in Phases I, II and III, respectively. M. pneumoniae predominated in Phases I and III (23.4% and 35.5%, respectively). In Phase II, respiratory syncytial virus (RSV) emerged as the primary pathogen (20.3%), whereas detection rates of influenza A virus (Flu A) and M. pneumoniae were at a low level (1.8% and 9.6%, respectively). In Phase III, both Flu A (15.8%) and M. pneumoniae epidemic rebounded, whereas RSV detection rate returned to Phase I level, and detection rates of Streptococcus pneumoniae and Haemophilus influenzae decreased significantly compared to those in Phase I. Detection rates of adenovirus and parainfluenza virus type 3 decreased phase by phase. Age-stratified analysis and monthly variations supported the above findings. Seasonal patterns of multiple pathogens were disrupted during Phases II and III. CONCLUSIONS: COVID-19 NPIs exhibited a distinct impact on CAP pathogen epidemic among children, with post-NPIs increases observed in M. pneumoniae and Flu A prevalence. Continuous pathogen monitoring is crucial for effective prevention and control of paediatric CAP.

The relationship between Mycoplasma and Kawasaki disease in pediatric patients: An updated systematic review and meta-analysis.

Objectives: This study aimed to clarify the relationship between Mycoplasma pneumoniae (M. pneumoniae) and Kawasaki disease by conducting an updated systemic review and meta-analysis of published studies. Materials and methods: Studies mentioning M. pneumoniae and Kawasaki disease before October 2022 were included in this meta-analysis. The pooled prevalence was calculated, and the log odds ratio in the random effects model was applied to estimate the pooled prevalence of M. pneumoniae infection in pediatric patients with Kawasaki disease. In addition, the clinical parameters, such as hemoglobin and erythrocyte sedimentation rate, were analyzed. Six studies with a total of 1,859 pediatric patients with Kawasaki disease were enrolled. The focused outcome was the pooled prevalence and clinical parameters. Results: The pooled prevalence of M. pneumoniae infection was statistically significant in pediatric patients with Kawasaki disease. In addition, the values of hemoglobin and erythrocyte sedimentation rate were significantly different between M. pneumoniae-infected and non-M. pneumoniae-infected patients with Kawasaki disease. Other clinical parameters were not significantly different between M. pneumoniae-infected and non-M. pneumoniae-infected patients with Kawasaki disease. Conclusion: The results suggest that M. pneumoniae infection is significantly prevalent in pediatric patients with Kawasaki disease. The lower values of hemoglobin and erythrocyte sedimentation rate in M. pneumoniae-infected patients with Kawasaki disease might be needed to investigate further.

Risk factors for death in children with critical and severe hand-foot-and-mouth disease in Chongqing, China: An observational study.

Hand-foot-and-mouth disease (HFMD) is a common childhood infection that may lead to serious complications and even death. Globally, epidemics of HFMD are increasing each year, especially in China. This study aimed to identify risk factors for death in children with critical and severe HFMD in Chongqing, China.We performed an observational study involving patients with critical and severe HFMD admitted to the Children's Hospital of Chongqing Medical University from January 2009 to December 2016. Overall, 179 patients aged 2 months to 16 years, were included; 127 died (non-survival group) and 52 survived (survival group); the case-fatality rate was 70.94%. Data comprising demographic characteristics, clinical symptoms and signs, and laboratory findings were collected. Non-conditional logistic regression analysis was performed to determine the risk factors for death.Univariate analysis showed that sex, coma, light-reflex insensitivity, pulmonary rales, pulmonary edema or hemorrhage, cold extremities, tachycardia, hypotension, white blood cell count, blood glucose concentration, serum lactate level, creatine kinase-MB isoenzyme level, and acidosis were associated with death (P < .05). Logistic regression analysis identified female sex (odds ratio [OR] 9.6, 95% confidence interval [CI] 3.0-30.2), light-reflex insensitivity (OR 4.4, 95% CI 1.4-13.1), tachycardia (OR 1.05, 95% CI 1.03-1.07), and higher serum lactate levels (OR 1.14, 95% CI 1.19-1.69) as independent risk factors; and longer onset-to-hospitalization time (OR 0.43, 95% CI 0.28-0.66) as an independent protective factor for death in children with critical and severe HFMD.Female sex, light-reflex insensitivity, tachycardia, and higher serum lactate level are potential independent risk factors; and longer onset-to-hospitalization time is possibly an independent protective factor for death in patients with critical and severe HFMD.

The novel gene mtb192 is a candidate marker for the detection of multidrug-resistant Mycobacterium tuberculosis strains.

BACKGROUND: Multi-drug resistant tuberculosis (TB) is one of the most main threats to the global TB control work at present. And it's very difficult to detect. From a screen of differentially expressed genes in multidrug-resistant tuberculosis (MDR-TB) strains, we identified a new gene, mtb192. In the present study, we verified the association of mtb192 with TB drug resistance by detecting its expression in clinical isolates from paediatric TB patients. MATERIALS AND METHODS: The homology of mtb192 was analysed by gene blasting in GenBank. The drug resistance of clinical TB isolates was tested, and mtb192 gene expression was compared using reverse transcription polymerase chain reaction (RT-PCR) and quantitative PCR. RESULTS: Gene homology suggested that mtb192 is a new gene sequence. Among the 120 clinical isolates, 14 were positive for mtb192, including 12 in the MDR group, 2 in the single drug-resistant group, 1 in the poly-resistant group, and 1 in the sensitive group. The mtb192 positive expression rate was significantly higher in the MDR group than all other groups, and the mtb192 mRNA expression level was significantly higher in the MDR group than in the non-MDR group. CONCLUSIONS: The new gene mtb192 showed significantly higher expression in MDR-TB strains and could be related to the development of MDR in Mycobacterium tuberculosis, highlighting it as a new genetic marker in the detection of MDR-TB.

Screening and comparison of differentially expressed genes between one MDR-TB strain and the virulent M. tuberculosis H37Rv.

To screen and compare the differentially expressed genes between one MDR-TB strain separated from one child patient and the virulent Mycobacterium tuberculosis H37Rv, suppression subtractive hybridization (SSH) technology was used to build a library of cDNAs that were differentially expressed in the MDR and H37Rv. From this cDNA library, genes that were expressed in the MDR-TB but not in the H37Rv were selected for gene sequencing and homology analysis; 113 positive clones were obtained, their cDNA fragments were sequenced, and homology analysis was performed. Four novel sequences were identified. The results provide a partial list of genes differentially expressed in MDR-TB and four novel genes were found. Identification of these genes may contribute to our understanding of MDR-TB development.

Construction, screening and evaluation of a derivative recombinant adenovirus for the optimal siRNA targeting of a novel gene (HA117).

At this study, we screened for an optimal siRNA to target a novel gene named HA117 and constructed and evaluated a recombinant adenovirus carrying the DNA template for the transcription of the optimal HA117 siRNA to examine the function of HA117 and its possible mechanism of action in CW-2 cell lines. An HAi5-carrying recombinant adenovirus (Ad-HAi5) was successfully constructed and evaluated. The results show that, among five pairs of DNA templates, siRNA transcribed from HAi5 gave the strongest interference with the novel gene HA117. The expression of the exogenous HA117 gene increased drug resistance in CW-2 cells. We hypothesized that this action may be a result of HA117 through inhibiting apoptosis in CW-2 cells.

Evaluation of biodistribution and safety of adenovirus vector containing MDR1 in mice.

BACKGROUND: The aim of this study is to examine the safety and distribution of Ad-EGFP-MDR1, an adenovirus encoding human multidurg resistance gene (human MDR1), in the mice colon carcinoma model. METHODS: After bone marrow cells (BMCs) were infected with Ad-EGFP-MDR1, they were administered by intra bone marrow-bone marrow transplantation (IBM-BMT). Total adenovirus antibody and serum adenovirus neutralizing factor (SNF) were determined. Biodistribution of Ad-EGFP-MDR1 was detected by in situ hybridization and immunohistochemistry. The peripheral hematocyte white blood cell (WBC), haemoglobin (Hb), red blood cell (RBC) and platelet (Plt) counts were analyzed. RESULTS: Neither total adenovirus antibody nor SNF increased weeks after BMT. In situ hybridization and immunohistochemistry demonstrated concordant expression of human MDR1 and P-gp which were found in lung, intestine, kidney and BMCs after BMT, but not detected in liver, spleen, brain and tumor. No significant abnormality of the recovery hematocyte was observed on Day 30 after treatment. CONCLUSION: The results indicate that IBM-BMT administration of a replication defective adenovirus is a feasible mode of delivery, allowing exogenous transference. The findings in this study are conducted for the future long-term studies of safety assessment of Ad-EGFP-MDR1.

[Growth and differentiation effect on HL60 cells by adenovirus-mediated exogenous wnt5a gene modification on human bone marrow mesenchymal stem cells].

OBJECTIVE: To study the effect of human bone marrow mesenchymal stem cell (bMSCs) modified by the adenovirus-mediated exogenous wnt5a gene on the hematopoietic function of bone marrow and the inhibition of the growth of HL60 leukemia cells. METHODS: BMSCs were identified through flow cytometry and modified by Ad5-wnt5a, The transfection rate of wnt5a gene in bMSCs was detected by RT-PCR. The cell growth curves were detected in different groups (bMSCs group, Ad5-GFP group, Ad5-wnt5a group). Ad5-wnt5a-bMSCs and HL60 cells were co-cultured, the surface differentiation antigen (CD13, CD14, CD68) and cell cycles were detected by immunocytochemical and flow cytometry in different groups (HL60 cell group, HL60+bMSCs group, HL60+ Ad5-GFP group, HL60+ Ad5-wnt5a group), respectively. RESULTS: Adenovirus-mediated exogenous wnt5a gene was transfected into bMSCs. The expression of differentiation antigens of CD14, CD68 in HL60+Ad5-wnt5a group were higher than those in control group (P < 0.05), the expression of differentiation antigen CD13 were not significant difference in different groups (P > 0.05). Compared with control group, the cell cycle in HL60+ Ad5-wnt5a group was blocked at G2 phase in the fourth day. CONCLUSION: Exogenous wnt5a gene can promote the growth of bMSCs, and induce HL60 cells to differentiation and maturation.

[Clinical significance of HA117 expression in children with acute leukemia].

OBJECTIVE: To explore the role of the expression of HA117 gene in bone marrow mononuclear cells (BMMNC) with acute leukemia and multidrug resistance. METHODS: HA117 gene expressions in 36 children with acute leukemia and 10 children with Idiopathic thrombocytopenic purpura (ITP) were tested using semi quantitative reverse transcriptase polymerase chain reaction (RT-PCR) technique. RESULTS: The HA117 gene was expressed in 75% of children with acute leukemia. There was no significant difference in HA117 gene expression between children with acute lymphoblastic leukemia (ALL, 69.57%) and children with acute myeloid leukemia (AML, 91.67%). But the semi-quantitative expression of HA117/beta-actin in AML childern was significantly higher than in ALL children (q=4.5852, P<0.01). The expressions of HA117 gene and HA117/beta-actin in both ALL and AML children were significantly higher than in ITP children chi2=5.05, 8.81; q=4.4612, 6.9695; P<0.05). The remission patients had lower expression of HA117/beta-actin and similar expression of HA117 compared with initially diagnosed patients. The remission patients had higher expression of HA117 gene and similar expression of HA117/beta-actin compared with patients with ITP. The non-remission patients had higher expression of HA117/beta-actin than remission patients and ITP patients (q=3.1705, 4.4102, P<0.05), but no significant difference from initially diagnosed patients (q=0.5470, P>0.05). CONCLUSION: The expression of HA117 gene is high in the BMMNC of initially diagnosed and non-remission patients with AL. But the remission patients have similar semi-quantitative expression of HA117 as patients with ITP, which indicates that a quantitative testing is more important. The expression of HA117 gene decreases with the improvement of the illness. HA117 is one of the factors that may affect the clinical remission of AML. The new gene HA117 may also be associated with multidrug resistance of leukemia.

HA117 gene increased the multidrug resistance of K562 cells in vitro: an investigation to the function of a novel gene related to drug resistance.

OBJECTIVE: A novel multi-drug resistance gene named as HA117 has been screened and cloned in multidrug resisitant leukemia cell lines in our previous research, but its function is still unknown. In this study, HA117 gene was investigated whether it could increase the drug resistance in chronic myelogenous myeloid leukemia cell line K562. METHODS: HA117 was cloned and adenovirus vectors were constructed with the HA117 gene (Adeasy-HA117). K562 cells were infected by Ad-HA117 to get the K562/Ad-HA117 cells with HA117 gene expression. The infection efficiency and the multiplicity of infection (MOI) were detected by fluorescence and flow cytometry. The expression of HA117 gene was detected by RT-PCR. The drug sensitivities of K562/Ad-HA117 cells were detected by Methyl Thiazolyl Tetrazolium (MTT) assay. RESULTS: Recombinant adenovirus vectors were constructed and a MOI of 100 is most suitable to infect K562 cells. The infected K562 cells demonstrated in vitro production of HA117 mRNA as measured by reverse-transcriptase polymerase chain reaction. There were no significant changes in K562/Ad-HA117 cells growth, while the drug sensitivities of K562/Ad-HA117 cells to Vincristine, Adriamycin, Etoposide, Daunorubicin, Mitomycin and Cyclophosphamide decreased 4.44, 7.18, 3.01, 9.53, 3.48 and 3.61 times than that of uninfected K562 cells, respectively (P < 0.05). CONCLUSION: Expression of the novel gene HA117 could significantly increased the multi-drug resistance of K562 cells, which indicated that HA117 is a functionally relevant multidrug resistance gene.

Screening and cloning of multi-drug resistant genes in HL-60/MDR cells.

OBJECTIVE: To screen and clone multi-drug resistance (MDR) related genes in MDR acute myeloid leukemia cells (HL-60/MDR). METHODS: HL-60/MDR was established using All-Trans Retinoic Acid. With the HL-60 cells as "tester" and HL60/MDR as "driver", the cDNA library of HL-60/MDR was established by suppression subtractive hybridization. Then 12 of the resulting subtracted cDNA clones were selected for DNA sequencing and homology analysis. The obtained expressed sequence tags (ESTs) were analyzed with the GenBank BLASTN program to identify sequence homologies to known genes. RESULTS: The HL-60/MDR cells had different multi-drug resistance to six kinds of chemotherapeutic drugs. The 211 positive gene clones in differential cDNA library of HL-60/MDR cells were amplified with PCR and 46 gene clones exhibited differential expression (ratio >3). Twelve gene clones with significant differential expression (ratio >5) were screened out to homology analysis. Of these, 11 matched known genes and the rest 1 showed no significant homology to human or non-human known sequences. It was named as gene clone HA117. CONCLUSIONS: This effort provides the partial list of genes differential expressed in HL-60/MDR cells and a novel gene HA117 was found to be related to MDR. Identification of these genes contributes to our understanding of MDR development, and potentially provides candidate target genes to overcome MDR.

[Effect of siRNA targeting VEGF on cell apoptosis and the expression of survivin in K562 cells.].

OBJECTIVE: To study the effect of adenovirus vector-mediated siRNA targeting vascular endothelial growth factor(VEGF) on apoptosis and the expression of survivin in K562 cells. METHODS: K562 cells were infected with recombinant adenovirus Ad5-VEGFsi for 72 hours as experimental group (K562/Ad5-VEGFsi), and empty vector group (K562/Ad5) and blank control group (K562) as controls. VEGF mRNA and survivin mRNA expression were determined by RT-PCR. The protein levels of VEGF and survivin were measured by ELISA and Western blot, respectively. The apoptosis of K562 cells was detected by flow cytometry. RESULTS: The levels of VEGF and survivin mRNA expression in experimental group cells were significantly decreased (P < 0.01). The protein concentration of VEGF in experimental group supernatant was (1121 +/- 15) pg/ml, being lower than that in empty vector group \[(1290 +/- 28) pg/ml\] and black control group \[(1303 +/- 28) pg/ml\] (P < 0.01), and the level of survivin protein in experimental group (0.26 +/- 0.11) was significantly reduced compared with that in blank control group (0.74 +/- 0.10) (P < 0.01). The apoptosis rate of K562/Ad5-VEGFsi cells (16.45 +/- 0.14)% was higher than those of K562/Ad5 cells (3.54 +/- 0.17)% and K562 cells (2.56 +/- 0.20)% (P < 0.01). CONCLUSIONS: VEGF can up-regulate the expression of survivin. After inhibition of VEGF by RNAi, the expression of survivin is decreased subsequently and the rates of cell apoptosis are increased.