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Objective To investigate the respiratory pathogens and clinical features in children with acute exacerbation of bronchial asthma. Methods Nasopharyngeal swabs were collected from 225 children with acute exacerbation of bronchial asthma, aged <14 years, who attended the outpatient service or were hospitalized from August 2017 to August 2019. Quantitative real-time PCR was used to detect 12 pathogens, i.e., respiratory syncytial virus (RSV), human rhinovirus (HRV), influenza virus A (IFVA), influenza virus B (IFVB), parainfluenza virus types 1-3 (PIV1- 3), human metapneumovirus (HMPV), adenovirus (ADV), Bordetella pertussis (BP), Chlamydia pneumoniae (CP), and Mycoplasma pneumoniae (MP). Results The overall detection rate of virus was 46.2% (104/225), and 7 kinds of viruses were detected, i.e., HRV (19.6%, 44/225), ADV (16.0%, 36/225), IFVB (5.8%, 13/225), RSV (4.9%, 11/225), IFVA (3.6%, 8/225), PIV3 (1.8%, 4/225), and HMPV (0.4%, 1/225). Of all pathogens, BP had the highest detection rate of 28.4% (64/225), and the detection rates of MP and CP were 16.4% (37/225) and 0.4% (1/225), respectively. The mild exacerbation group had a higher detection rate of BP than the severe exacerbation group (P<0.05), while the severe exacerbation group had significantly higher detection rates of RSV and MP than the mild exacerbation group (P<0.05). There were significant differences in the proportion of children with paroxysmal cough, spasmodic cough, fever, lung rales and abnormal lung imaging findings among the simple BP infection, simple virus infection and simple MP infection groups (P<0.05). Conclusions BP, HRV, and MP are common respiratory pathogens detected in children with acute exacerbation of bronchial asthma, and respiratory virus infection is an important pathogen of acute exacerbation of asthma in children. Acute exacerbation of asthma caused by different pathogens has different clinical features and severities. [ABSTRACT FROM AUTHOR]

Objective To study the expression of interferon-λ1 (IFN-λ1) in respiratory epithelial cells in children with human rhinovirus (HRV) infection. Methods Sputum samples and nasopharyngeal swabs were collected from the children who were hospitalized due to acute respiratory infection from February to October, 2017. Bacterial culture was performed, and nucleic acid test was performed for 11 respiratory pathogens. A total of 90 children with positive HRV alone were enrolled as the HRV infection group, and 95 children with positive respiratory syncytial virus (RSV) alone were enrolled as the RSV infection group. A total of 50 healthy children who underwent outpatient physical examination during the same period of time and had negative results for all pathogen tests were enrolled as the healthy control group. Nasopharyngeal swabs were collected from all groups, and quantitative real-time PCR was used to measure viral load and the mRNA expression of IFN-λ1. Results In the HRV infection group, there was no significant difference in the mRNA expression of IFN-λ1 between boys and girls and across all age groups (P>0.05). In the HRV infection group, there was no correlation between the mRNA expression of IFN-λ1 and HRV load (P>0.05). The mRNA expression of IFN-λ1 in the HRV infection group was significantly higher than that in the healthy control group (P<0.05), but significantly lower than that in the RSV infection group (P<0.05). Conclusions HRV can induce the expression of IFN-λ1 in respiratory epithelial cells, suggesting that IFN-λ1 may play an important role in anti-HRV infection in children. [ABSTRACT FROM AUTHOR]

Propagation of partially coherent flat-topped beams (PCFT) through turbulent atmosphere was studied with the help of generalized Huygens-Fresnel integral and the matrix optics. The analytic expression for the cross-spectral density matrix of partially coherent flat-topped beam was derived. Through analyzing the properties of the cross-spectral density and the degree of coherence of PCFT in turbulent atmosphere, the dependence of sensitivity of PCFT to turbulence on propagating distance and beam order number N was investigated. The results show that a PCFT beam with larger propagating distance and lower beam order is more affected by atmospheric turbulence, while the dependence of PCFT order N, coherence properties itself and propagating distance on the spectral degree of coherence becomes weaker due to the existence of atmospheric turbulence. [ABSTRACT FROM AUTHOR]

A boy, aged 11 years, was admitted due to intermittent fever for 15 days, cough for 10 days, and "hemoptysis" for 7 days. The boy had fever and cough with left neck pain 15 days ago, and antibiotic treatment was effective. During the course of disease, the boy developed massive "hemoptysis" which caused shock. Fiberoptic bronchoscopy revealed a left pyriform sinus fistula with continuous bleeding. In combination with neck and vascular imaging examination results, the boy was diagnosed with internal jugular vein injury and thrombosis due to congenital pyriform sinus fistula infection and neck abscess. The boy was improved after treatment with temperature-controlled radiofrequency ablation for the closure of pyriform sinus fistula, and no recurrence was observed during the follow-up for one year and six months. No reports of massive hemorrhage and shock due to pyriform sinus fistula infection were found in the searched literature, and this article summarizes the clinical features, diagnosis, and treatment of this boy, so as to provide a reference for the early diagnosis of such disease and the prevention and treatment of its complications.

Objective: To investigate the distribution characteristics and clinical features of Burkholderia cepacia infection in children., Methods: A retrospective analysis was performed for the clinical data of 16 children with Burkholderia cepacia infection who were hospitalized between June 2012 and September 2017., Results: All 16 children with Burkholderia cepacia infection were sporadic cases. A total of 16 strains of Burkholderia cepacia were isolated, among which 8 were detected by sputum culture, 5 were detected by blood culture, 2 were detected by tracheal intubation tip culture, and 1 was detected by lung biopsy culture. Of the 16 children, there were 11 boys and 5 girls, with an age of 5 days to 6 years, and the children aged <1 year accounted for 69%. As for department distribution, 10 children were in the PICU/NICU and 6 were in the general wards. As for clinical manifestations, one child had disseminated intravascular coagulation, and the other 15 children had pulmonary infection, among who 11 had severe pneumonia (8 of them underwent mechanical ventilation during treatment). As for underlying diseases, 2 had severe congenital heart disease, 4 had primary immunodeficiency, 3 were highly suspected of immunodeficiency or inherited metabolic diseases, 1 had tracheal stenosis, 1 had Kawasaki disease, 1 was a preterm infant with bronchopulmonary dysplasia, 1 had severe cleft lip and palate, and 3 had no definite underlying diseases. Of all the children, 7 also had infections with adenovirus and Mycoplasma. The average length of hospital stay was 20.3 days for all children, and 12 were improved and 4 died after treatment. All 16 strains of Burkholderia cepacia had a drug resistance rate of 100% to amikacin and gentamicin and ≥80% to ampicillin/sulbactam and ticarcillin/clavulanic acid, as well as the lowest drug resistance rate to levofloxacin., Conclusions: Burkholderia cepacia is an opportunistic pathogen often found in immunocompromised children and can produce drug resistance. The presence or absence of underlying diseases should be considered during anti-infective therapy. The children with Burkholderia cepacia infection often have a poor prognosis, and an understanding of the disease spectrum of Burkholderia cepacia infection helps with clinical diagnosis and treatment.

This study aimed to investigate antibody levels of the newer human enteroviruses (EV) A71, A90, and B87 in the population of Shandong Province, and provide a scientific basis for the development of prevention and control measures. In this study, serum specimens were collected from 400 individuals living in Yantai city, Shandong Province in 2010. EV-A71, A90, and B87 antibodies were detected using neutralization tests, and the results were analyzed by statistical methods. It was found that the positive neutralizing antibody rates of EV-A71, A90 and B87 in the population were 46.0%, 8.8%, and 47.0%, respectively. Their geometric mean titers (GMT) were 1 : 5.20, 1 : 1.49, and 1 : 4.02, respectively. Positive antibody rates for EV-A71 and EV-B87 were lowest in the 1-yr and 7-mo age groups, respectively. Positive rates increased gradually with age, and become consistent in the population aged >5 years. Positive antibody rates of EV-A90 were consistent across all age groups. Maternal antibody levels of EV-A71 declined rapidly after birth, and the increase in seroprevalence among 3-7 years old children implied that most EV-A71 infections occurred in preschool and early elementary school children. High positive antibody rates of EV-B87 in healthy individuals, especially children, implied that there may be an immune barrier within the general population. The population monitoring of EV-A90 should be strengthened, as its positive antibody rate is low.

We wished to analyze the genetic characterization of echovirus 11 (Echo11) from samples of environmental sewage in Shandong Province (China). The VP1 coding region was typed as the strains were amplified. Phylogenetic analyses on the VP1 sequences from these isolates, strains isolated from AFP cases in the period 1994-2010 and others published in GenBank were conducted. From 2011 to 2012, 94 Echo11 strains were isolated from samples of environmental sewage in Jinan and Linyi City in Shandong Province. Numbers of Echo11 were seasonal and reached peaks in the summer and autumn in both cities; A- mong these isolates, nucleotide (nt) identities were 89.5%-100.0% whereas amino acid (aa) identities were 95.4%-100.0%. The nt and aa identities were 76.6%-79.7% and 90.4%-92.5% between those strains and the prototype (Gregory) strain of Echo11, respectively. All isolates from Shandong Province were the A genotype and the strains evolved very rapidly, which suggested that several transmission chains was co-circulating. We described the temporal fluctuation and genetic characterization of Echo11 isolates from surveillance of environmental sewage in Shandong Province, thereby providing important information for exploring the dynamic change and genetic variation of circulating human enteroviruses in this Province in China.

To analyze the genetic characteristics of echovirus 6 (E6) isolated from meningitis and encephalitis cases in Shandong Province, China, we collected cerebrospinal fluid samples from meningitis and encephalitis cases in Shandong Province from 2007 to 2012 for virus isolation. Viral RNAs were extracted from positive isolates, and complete VP1 coding regions were amplified by RT-PCR and sequenced. Homology comparison and phylogenetic analysis were performed. Six isolates were identified as E6 by microneutralization assay and molecular typing. The homology analysis showed that the six isolates had 78. 6%-99. 8% nucleotide and 95. 5%-100. 0% amino acid identities with each other, as well as 76. 9%-78. 4% nucleotide and 92. 3%-95. 1% amino acid identities with the prototype strain (D' Amori). The phylogenetic analysis based on the integrated VP1 sequences indicated that all Shandong E6 isolates could be separated into four clusters, designated as A, B, C, and D. The six E6 isolates belonged to clusters A, B, and D. Our study reveals high genetic differences between Shandong E6 isolates and suggests different transmission lineages of E6 co-circulated in Shandong Province.

Human Enterovirus HEV 74 is a new member of species Human enterovirus B (HEV-B). To understand its evolution and restructuring characteristics, we report the complete genome sequence of a HEV74 strain 05293/SD/CHN/2005(abbreviated as 05293) isolated from an acute flaccid paralysis (AFP) case in Shangdong Province, China, 2005. Analysis of the complete genomic sequence of 05293 showed that its genome was collinear with that of previously described 2 HEV74 strains, except for insertions and deletions at the 5'NTR and the 3 NTR regions. The complete genome sequence of strain 05293 displayed 80. 8% nucleotide and 96% amino acid identity to the prototype strain USA/CA75-10213, and 80. 6% and 95. 9% to another isolated strain Rikaze-136. The P1, P2 and P3 coding regions of strain 05293 displayed 81. 5%, 80. 0%, 79. 7% nucleotide and 95. 9%, 96. 0%, 96.2% amino acid identity to the prototype strain USA/CA75-10213, and 81. 9%, 78. 8%, 79. 5% and 95. 9%, 96. 1%, 95. 7% to strain Rikaze-136, respectively. The phylogenetic tree and Simplot analysis on 05293 and HEV-B genome sequences were performed, and the result indicated frequent recombination within HEV-B.

To identify the pathogen of acute hemorrhagic conjunctivitis (AHC) in Shandong Province in 2010, eye mucous swab samples were collected from 26 patients in Qingdao and Linyi City. Real time-PCR assays for EV70, CVA24 and Adenovirus were performed on these samples. The result showed 17 samples (65.39%) were CVA24 positive while all the samples for HEV70 and Adenovirus detection were negative, which implied that CVA24 was the causative pathogen of this outbreak. A total of 10 virus strains isolated on Hep-2 cells were identified as CVA24 through VP1 amplification and nucleotide sequence analysis. The nucleotide and amino acid homologies on VP1 region among these isolates were 99.3%-100.0% and 99.5%-100.0%, respectively, and the strains aggregated together to one clade in phylogenetic tree. These results showed that the CVA24 circulating in Qingdao and Linyi City belonged to one transmission chain. Shandong CVA24s segregated into 5 different clades, and great nucleotide divergence was observed be tween AHC isolates and others.

Objective: To investigate the pathogen spectrum constitution of HEV related to acute meningitis/encephalitis syndrome (AMES) and to analyze the genetic characterization of the echovirus 30 (Echo30) isolates., Methods: Cerebrospinal fluid, stool, and/or throat swab specimens from 101 AMES cases were collected for virus isolation with RD and HEp-2 cell lines in Linyi city from April to December, 2010. After typing by neutralization test, the entire VP1 gene of the isolates were amplified by RT-PCR and sequenced. Homologous comparison was carried out and phylogenetic analysis were performed., Results: HEVs were isolated from 47 specimens of 34 patients (4 from cerebrospinal fluid, 18 from throut swab and 25 from stool), with 11 Echo30 isolates identified by microneutralization assay and molecular typing method. In alignment of VP1 sequences with global Echo30 isolates, relative high nucleotide homologies (91.2% - 95.4%) with Taian, Zhangqiu and Jiangsu isolates and high divergences (17.9% -19.6%) with prototype strain were observed. Nucleotide divergences among Linyi isolates were 0 - 10.2%, and 3 lineages were revealed via phylogenetic analysis, reflecting 3 transmission chains of Echo30 co-circulated in Linyi city, 2010., Conclusion: Echo30 was the predominant serotype of AMES cases in Linyi city, 2010. These isolates possessed considerable divergence with Echo30 from other countries.

To investigate the genetic characteristics of poliovirus isolates from environmental sewage surveillance in Shandong province, we collected sewage samples in Jinan and Linyi City. Serotyping and VP1/ 3D sequencing were performed on polioviruses isolated from the concentrated sewage samples, and VP1 mutation and recombination were analyzed. Thirty-two of sewage samples were collected, and polioviruses were detected in 10 of the samples with a positive rate of 31.3%. Eighteen Sabin strains were isolated including three type 1, nine type 2, and six type 3 polioviruses, and the number of nucleotide substitutions in VP1 coding region varied from 0 to 4. Recombination was found in three Sabin 2 and four Sabin 3 polioviruses. Analysis of neurovirulence sites of VP1 revealed that one Sabin 1 vaccine strain had a nucleotide change of A to G at nt 2749, one Sabin 2 strain had a nucleotide change of A to G at nt 2908, three Sabin 2 strains had a nucleotide change of U to C at nt 2909, and all six Sabin 3 strains had a nucleotide change of C to U at nt 2493. Poliovirus vaccine strains could be isolated from environmental sewage with a high rate of gene recombination and back mutation of neuvirulence-associated sites. None of wild-type poliovirus or vaccine-derived poliovirus was detected.

Human Enterovirus C group (HEV-C) includes 17 serotypes, which can not be serotype-identified by neutralization test using antiserum pool for NPEV. In order to elucidate the genotypes and molecular evolution of HEV-C in Shandong Province, We selected the strains isolated from AFP cases between 1994-2009 to perform reverse transcriptase-polymerase chain reactions (RT-PCR) by the primers specific for entire VP1 coding gene of HEV-C and sequencing. The phylogenetic tree was then constructed among these VP1 nucleotide sequences and other prototype strains. Totally 12 Shandong local strains were obtained and separated into 4 genotypes, CVA20, CVA21,CVA24 and EV 96. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct from prototype strains in each genotype. This report showed that different genotype HEV-C strains spread widely in Shandong Province.

In order to study the genotypes and molecular evolution of human enterovirus (HEV) A species in Shandong Province, Stool samples were collected from AFP and HFMD patients in Shandong Province and virus isolation was performed. Reverse Transcription-Polymerase Chain Reactions (RT-PCR) specific for EV71 and CVA16 were performed with the virus isolates from HFMD patients. Positive isolates were selected for entire VP1 coding gene amplification and sequencing. Isolates with negative PCR results and isolates from AFP patients were selected for entire VP1 coding gene amplification and sequencing using primers specific for HEV A species. Phylogenetic tree was constructed among these VP1 nucleotide sequences and of other strains. Altogether 293 strains classified into 8 genotypes were isolated. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct with prototype strains in every genotype. This report presents an overview of HEV-A in Shandong Province.

Objective: To study the protective effects of tetramethylpyrazine (TMPZ) on rat myocardial cells infected by Coxsackie virus B3 (CVB3) and its signal transduction mechanism., Methods: The cultured myocardial cells of neonatal Sprague-Dawley rats were randomly treated with CVB3, CVB3+TMPZ (100 micromol/L), TMPZ (100 micromol/L) (negative control) or DMEM (blank control). After treatment, the beating rate of myocardial cells and the LDH activity in the culture fluid were measured. Cell viability was ascertained with MTT assay. Western blot was used to study the expression of nuclear factor kappa-B (NF-kappaB) protein in myocardial cells., Results: The beating rate of myocardial cells in the untreated CVB3 infection group was significantly lower than that in the TMPZ-treated CVB3 infection group (32.0+/-3.6 bpm vs 84.3+/-3.5 bpm, P<0.01). The LDH activity and NF-kappaB expression in the TMPZ-treated CVB3 infection group was significantly reduced when compared with untreated CVB3 infection group (P<0.05, P<0.01, respectively). Cell viability 7 days after CVB3 infection in the TMPZ-treated group was higher than that in the untreated CVB3 infection group (86.7+/-2.7% vs 35.3+/-3.4%; P<0.01)., Conclusions: TMPZ can provide protective effects on rat myocardial cells infected by CVB3, possibly by an inhibition of the activity of NF-kappaB in myocardial cells.

Objective: Previous research suggests that dexamethasone (Dex) pretreatment protects neonatal rats against hypoxic-ischemic brain damage (HIBD). Some of the pharmacological effects of baicalin (a traditional Chinese medicine extracted from Scutellaria baicalensis Georgi) are similar to Dex. This study was designed to explore the effect of baicalin on the neuronal apoptosis following HIBD in neonatal rats., Methods: Six-day-old Sprague-Dawley rats were randomly assigned into Control (without HI), HIBD, Dex-pretreatment and post-treatment, Baicalin-pretreatment and -post-treatment groups. HIBD was induced by ligating the left common carotid artery, followed by exposure to hypoxia. In the pretreatment groups either baicalin (16 mg/kg) or Dex (0.1 mg/kg) was administered to the rats 24 hrs before HIBD; in the post-treatment groups baicalin or Dex was given 30 minutes after HIBD. The rat pups were sacrificed on postnatal day 10, and brain tissues were harvested. Brain water content was determined, morphological changes were observed under a light microscope, and neuronal apoptosis was measured by terminal deoxynucleotidyl transferase mediated dUTP biotin nick end labeling (TUNEL) staining., Results: The brain water content and the number of apoptotic cells were significantly higher in the HIBD group than those of the Control group (P < 0.05). Both baicalin and Dex pretreatment decreased the brain water content from 88.9 +/- 1.7 % (HIBD group) to 87.4 +/- 0.7% (baicalin) or 87.3 +/- 0.6% (Dex) (P < 0.05) and the number of apoptotic cells were reduced from 251 +/- 28 (HIBD group) to 102 +/- 47 (baicalin) or 75 +/- 26 (Dex) (P < 0.05). Baicalin and Dex post-treatment had no effects on the brain water content and the number of apoptotic cells. Loss and degeneration of neurons could be observed in the HIBD group. Baicalin and Dex pretreatment significantly alleviated neuronal injury, but post-treatment did not., Conclusions: Pretreatment with baicalin, as with Dex, has a protective effect against HIBD in neonatal rats, but baicalin or Dex post-treatment do not reverse the neuronal injuries.