The proliferation and invasion of osteosarcoma are inhibited by miR-101 via targetting ZEB2.

Having a better grasp of the molecular mechanisms underlying carcinogenesis and progression in osteosarcoma would be helpful to find novel therapeutic targets. Different types of cancers have presented abnormal expression of miRNA-101 (miR-101). Nevertheless, we still could not figure out what expression of miR-101 in human osteosarcoma is and its biological function. Thus, we conducted the present study to identify its expression, function, and molecular mechanism in osteosarcoma. We detected the expression of miR-101 in osteosarcoma samples and cell lines. The effects of miR-101 on osteosarcoma cells' proliferation and invasion were evaluated. Luciferase reporter assay was applied to identify the direct target of miR-101. Compared with adjacent normal specimens and normal bone cell line by using qPCR, the expression levels of miR-101 in osteosarcoma specimens and human osteosarcoma cell lines distinctly decreased. According to function assays, we found that overexpression of miR-101 significantly inhibited the cell proliferation and invasion in osteosarcoma cells. Moreover, we confirmed that zinc finger E-box binding homeobox 2 (ZEB2) was a direct target of miR-101. In addition, overexpression of ZEB2 could rescue the inhibition effect of proliferation and invasion induced by miR-101 in osteosarcoma cells. MiR-101 has been proved to be down-regulated in osteosarcoma and has the ability to suppress osteosarcoma cell proliferation and invasion by directly targetting ZEB2.

Epidemiological and clinical characteristics of respiratory viral infections in children in Shanghai, China.

Acute respiratory tract infections (ARTIs) due to various viruses are not only the most common causes of upper and lower respiratory infection but are also major causes of morbidity and mortality in children. In this study, we investigated the prevalence and clinical characteristics of children with virus-related ARTIs and determined the spectrum of respiratory viruses and their correlation with meteorological variables in Jiading District, Shanghai, China. Nasopharyngeal swabs from 2819 children with ARTIs were collected from August 2011 to December 2014, and used for detection of respiratory viruses by multiplex RT-PCR. Seventeen respiratory viruses were detected among 691 (24.5 %) of 2819 patients. The highest prevalence of respiratory viruses was detected in the age group of less than 1 year (29.0 %), and the prevalence decreased with age. This suggests that children less than one year old are the most susceptible to infection. Influenza virus (IFV) was the most frequently detected virus (5.8 %), followed by parainfluenza virus (PIV) (5.7 %), enterovirus (EV) (4.3 %), and respiratory syncytial virus (RSV) (3.6 %). Statistical analysis showed that epidemics of IFV, PIV and EV had distinct seasonal variations. Mean monthly temperature appeared to be the only meteorological factor associated with IFV and PIV infection. These findings will provide valuable information for decision-making, prevention and treatment of ARTIs in children.

[Association between parainfluenza virus infection and climatic factors in children].

OBJECTIVE: To study the association between acute respiratory human parainfluenza virus (HPIV) infection and climatic factors in children. METHODS: A total of 2 526 throat swab samples were collected from children with acute respiratory infection who visited the Pediatric Clinic of Shanghai Jiading Nanxiang Hospital between 2011 and 2013. HPIV was detected by multiplex RT-PCR. Related meteorological data were collected, including monthly mean temperature, monthly mean humidity, and monthly total rainfall. The association between HPIV detection rate and climatic factors was analyzed by Spearman's or Pearson test. RESULTS: During the three years, the overall HPIV detection rate was 5.62% (142/2 526), and HPIV-1 was the most common type (46.5%), followed by HPIV-3 (31.0%), HPIV-2 (17.6%), and HPIV-4 (4.9%). There were significant differences in the detection rates of HPIV-1 and HPIV-2 in different seasons, and the detection rates of both were the highest in summer (P<0.05). HPIV positive rate was positively correlated with monthly mean temperature (r=0.598; P<0.01) and monthly total rainfall (rs=0.602; P<0.01). CONCLUSIONS: The activity of HPIV in children is correlated with climatic factors, particularly temperature and rainfall.

Genetic variation of human respiratory syncytial virus among children with fever and respiratory symptoms in Shanghai, China, from 2009 to 2012.

Human respiratory syncytial virus (HRSV) of genus Pneumovirus is one of the most common pathogens causing severe acute lower respiratory tract infection in infants and children. No information on the genotype distribution of HRSV is available in East China (e.g. Shanghai). From August 2009 to December 2012, 2407 nasopharyngeal swabs were collected from outpatient children with fever and respiratory symptoms in Shanghai. HRSV infection was determined using a multiplex RT-PCR assay. The second hypervariable region (HVR2) of G protein gene of HRSV was amplified and sequenced from HRSV positive samples. Genotypes were characterized by phylogenetic analyses. Of 2407 nasopharyngeal samples, 184 (7.6%) were tested as HRSV positive. From 160 positive subjects with sufficient nasopharyngeal samples, 69 HVR2 sequences were obtained by RT-PCR and sequencing. Three HRSV epidemic seasons were observed from August 2009 to December 2012, and an extreme outbreak of HRSV occurred in the 2009-2010 epidemic season. A genotype shift of predominant HRSV strains from B group in the 2009-2010 epidemic season to group A in the subsequent epidemic seasons was observed. Ten HRSV genotypes, including four group A genotypes NA1, NA3, NA4, and ON1, and six group B genotypes BA9, BA10, SAB4, CB1, BAc, and BA?, were detected in Shanghai. Seven genotypes (NA1, BA9-10, SAB4, CB1, BAc and BA?) were found in the 2009-2010 epidemic season. The co-circulation of multiple genotypes was associated with the extreme outbreak of HRSV among children with fever and respiratory symptoms in the 2009-2010 epidemic season.

[Allergens and their relationships to childhood bronchial asthma in the Jiading District of Shanghai].

OBJECTIVE: To study allergens and their relationship to the occurrence of childhood bronchial asthma in the Jiading District of Shanghai. METHODS: Three hundred and eighty-two 4 to 12-year-old children with asthma in the remission stage from Nanxiang Hospital in the Jiading District of Shanghai were used as a case group (asthma group), and 402 children from two primary schools and two kindergartens in Jiading were enrolled by cluster sampling and served as control group. Parents of the children completed a questionnaire on living conditions and allergy-related disease history. Skin prick test (SPT) for 18 common allergens was carried out in both groups. In order to examine the effect of environment and living conditions on SPT results, children in the control group were further divided into two sub-groups according to birth place: migrant (219 cases) and resident (183 cases). RESULTS: SPT results revealed that the main allergens identified in the Jiading region were dermatophagoides farinae, house dust mites, shrimps, cockroaches, and dog hair. The SPT positive rate was 67.9% in the asthma group, and this was significantly higher than in the control group (31.8%) (P<0.01). The environment and living conditions in the migrant group were significantly different from the resident group (P<0.01), whereas the SPT positive rate for this group was significantly lower than in the resident group (P<0.01). CONCLUSIONS: Allergens in the Jiading region mainly originate from dermatophagoides farinae, household dust mites, shrimps, cockroaches and dog hair. Children with asthma are more susceptible to allergens. Environment and living conditions may be relevant, to a certain extent, to an SPT positive rate.

[Clinical characteristics of human bocavirus infection in 90 children].

OBJECTIVE: To study the clinical characteristics of human bocavirus (HBoV) infection in children. METHODS: Nasal and throat swab samples were collected in 843 children with lower respiratory tract infection. The multiple RT-PCR method was used to detect HBoV and six other common respiratory tract viruses. The clinical characteristics of HboV positive cases were investigated. RESULTS: Among 843 cases, 90 were HboV positive (10.7%), 131 were respiratory syncytial virus (RSV) positive (15.5%), 117 were influenza virus positive (13.9%), 84 were parainfluenza virus positive (10.0%), 55 were rhinovirus positive (6.5%), 48 were coronavirus positive (5.7%), and 33 were human metapneumovirus positive (3.7%). Of the 90 HBoV infected patients, 45 (50%) showed a co-infection with other respiratory tract viruses. Among them, 33 were infected with one other type of virus (37%), 11 (12%) were infected with two other types of virus, and 1 case (1%) was infected with other three viruses. The HBoV positive rate in children with wheezing was significantly higher than those without wheezing (17.0% vs 9.2%; P<0.01). The common clinical manifestations of HBoV-infected patients included frequent coughing, wheezing and fever. There were no significant differences in the frequency of wheezing between HBoV and RSV infected patients. CONCLUSIONS: HBoV positive rate detected from children with wheezing is higher than from children without wheezing, suggesting that apart from RSV, HBoV is another virus causing wheezing in children with respiratory tract infection. Co-infections of HBoV with other respiratory track viruses can be present in some patients.

Molecular monitoring of causative viruses in child acute respiratory infection in endemo-epidemic situations in Shanghai.

BACKGROUND: Numerous viruses are responsible for respiratory infections; however, both their distribution and genetic diversity, in a limited area and a population subgroup, have been studied only rarely during a sustained period of time. METHODS: A 2-year surveillance program of children presenting with acute respiratory infections (ARIs) was carried out to characterize the viral etiology and to assess whether using gene amplification and sequencing could be a reliable approach to monitor virus introduction and spread in a population subgroup. RESULTS: Using multiplex RT-PCR, 15 different respiratory viruses were detected within the 486 nasopharyngeal positive samples collected among 817 children aged <9-year old who presented with ARI during October 2006 to September 2008. A single virus was detected in 373 patients (45.7%), and two to four viruses in 113 patients (13.8%). The most frequent causative viruses were respiratory syncytial virus (RSV) (24.7%), human bocavirus (24.5%), and human rhinovirus (HRV) (15%). RSV was more prevalent in winter and among young infants. Cases of seasonal influenza A and B viruses were reported mainly in January and August. An increase in adenovirus infection was observed during the spring of the second year of the study. Sequence analyses showed multiple introductions of different virus subtypes and identified a high prevalence of the newly defined HRV-C species. A higher viral incidence was observed during the winter of 2008, which was unusually cold. CONCLUSIONS: This study supports the usefulness of multiplex RT-PCR for virus detection and co-infection, and for implementation of a molecular monitoring system for endemic and epidemic viral respiratory infections.

Correlation between bocavirus infection and humoral response, and co-infection with other respiratory viruses in children with acute respiratory infection.

BACKGROUND: Human bocavirus (HBoV), a recently discovered virus, is prevalent among children with respiratory tract infection throughout the world. Co-infection was frequently found in HBoV-positive patients. Thus, whether HBoV is responsible for the respiratory disease is still arguable. OBJECTIVES: A comprehensive study was carried out to integrate clinical and virological prevalence in HBoV-positive outpatient children, and to determine genetic and serologic characteristics of HBoV in Shanghai, China. STUDY DESIGN: Nasal/throat swabs and sera were obtained over a 2-year period from 817 children with respiratory tract infection to examine the presence of HBoV and its co-infection. The seroepidemiology of HBoV was studied by ELISA and Western blot against the capsid protein VP2-based fragment. Persistence of HBoV was also analyzed in 12 pairs of return-visit cases. RESULTS: HBoV was identified in 96 samples (11.8%). The co-infection rate with other respiratory viruses was 51%. IgM was detected in 55.7% of HBoV RT-PCR-positive patients, and in 72.7% of those who had high viral genome load. In addition, persistent viral DNA positivity was detected in 10 of 12 HBoV-positive cases tested, an average of 14 days later, and one child was still HBoV-positive after 31 days. CONCLUSION: HBoV was found frequently in children with respiratory tract symptoms associated with other respiratory viruses, and persisted in the respiratory tract and in serum and urine. The presence of IgM was significantly more prevalent in viremic patients and those diagnosed with high load of HBoV DNA in nasal/throat swabs.

Simultaneous detection of respiratory viruses in children with acute respiratory infection using two different multiplex reverse transcription-PCR assays.

A 4-tube multiplex RT-PCR (mRT-PCR), which showed higher sensitivity over conventional methods, was previously developed for the diagnosis of 14 viral pathogens of the respiratory tract. Herein the mRT-PCR was compared to the commercial Luminex mPCR-microsphere flow cytometry assay (Resplex II) which allows the detection of 12 different viruses. Eleven different viruses were identified in 91 nasopharyngeal swabs of children with acute respiratory infection, influenza A (IAV) and B, respiratory syncytial virus (RSV), human rhinovirus (hRhV), human echovirus, parainfluenza viruses (PIV) 1, 2, 3 and 4, human metapneumovirus (hMPV), and human coronavirus NL63. The results of the two techniques showed 53 and 40 positive patients by the Resplex II assay and mRT-PCR, respectively, with a concordance in 35 positive and 33 negative patients (74.7%). Individual RT-PCR tests were performed to control viruses not simultaneously detected by the two multiplex assays. The major virus misdiagnosed by mRT-PCR was IAV whereas the major viruses misdiagnosed by Resplex II were PIV1, 3 and 4. The mRT-PCR remains a simple, rapid, and specific assay for the specific detection of respiratory viruses, and can be easily implemented with standards in clinical laboratories at a low cost.

Evidence of recombination and genetic diversity in human rhinoviruses in children with acute respiratory infection.

BACKGROUND: Human rhinoviruses (HRVs) are a highly prevalent cause of acute respiratory infection in children. They are classified into at least three species, HRV-A, HRV-B and HRV-C, which are characterized by sequencing the 5' untranslated region (UTR) or the VP4/VP2 region of the genome. Given the increased interest for novel HRV strain identification and their worldwide distribution, we have carried out clinical and molecular diagnosis of HRV strains in a 2-year study of children with acute respiratory infection visiting one district hospital in Shanghai. METHODOLOGY/FINDINGS: We cloned and sequenced a 924-nt fragment that covered part of the 5'UTR and the VP4/VP2 capsid genes. Sixty-four HRV-infected outpatients were diagnosed amongst 827 children with acute low respiratory tract infection. Two samples were co-infected with HRV-A and HRV-B or HRV-C. By comparative analysis of the VP4/VP2 sequences of the 66 HRVs, we showed a high diversity of strains in HRV-A and HRV-B species, and a prevalence of 51.5% of strains that belonged to the recently identified HRV-C species. When analyzing a fragment of the 5' UTR, we characterized at least two subspecies of HRV-C: HRV-Cc, which clustered differently from HRV-A and HRV-B, and HRV-Ca, which resulted from previous recombination in this region with sequences related to HRV-A. The full-length sequence of one strain of each HRV-Ca and HRV-Cc subspecies was obtained for comparative analysis. We confirmed the close relationship of their structural proteins but showed apparent additional recombination events in the 2A gene and 3'UTR of the HRV-Ca strain. Double or triple infections with HRV-C and respiratory syncytial virus and/or bocavirus were diagnosed in 33.3% of the HRV-infected patients, but no correlation with severity of clinical outcome was observed. CONCLUSION: Our study showed a high diversity of HRV strains that cause bronchitis and pneumonia in children. A predominance of HRV-C over HRV-A and HRV-B was observed, and two subspecies of HRV-C were identified, the diversity of which seemed to be related to recombination with former HRV-A strains. None of the HRV-C strains appeared to have a higher clinical impact than HRV-A or HRV-B on respiratory compromise.