As the second generation macrolide antibiotic, except for antibacterial effects, azithromycin can down-regulate inflammatory responses, reduce mucus secretion and inhibit bacterial biofilms.In addition to the infectious diseases caused by atypical pathogens, viral or bacterial, chronic diseases including cystic fibrosis, chronic rhinosinusitis, asthma, gastroparesis and otherdiseases can be treated with azithromycin.Clinicians should pay more attention to drug resistance and adverse reactions in infant.The article will review the progress of clinical application of azithromycin in recent years and the strategies for drug resistance and adverse effects.

Objective To observe the effect of visible light on apoptosis of cultured human retinal pigment epithelium (RPE) cells. Methods Being the light source,500lx,(2 000?500)lx and (3 400?200)lx cold white light were used. The duration of exposure was 0,6,12 and 24 hours respectively. Apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling, Annexin V flunorescein isothiocyanate/Propidium iodium labelling and flow cytometry. Results Apoptosis and necrosis were found in cultured human RPE cells which were exposed to visible light.(1)A significant increase in apoptotic and necrotic percentages was consistent with a higher light intensity.(2)Apoptosis was the main response to shorter (6 h and 12 h) exposure duration,while necrosis was more pronounced correlated to the prolongation of post exposure culture ( P 500 lx) increases the proportion of apoptosis and necrosis of human RPE cells in vitro.The extent is related to exposure intensity and duration. It demonstrates that the lower intensity and the shorter duration of exposure to light are, the more pronounced apoptotic percentages are observed,otherwise necrosis.

Objective To observe the effect of exogenous basic fibroblast growth factor (bFGF) on apoptosis of cultured human retinal pigment epithelial (RPE) cells exposed to visible light,and determine the role of bFGF, fibroblast growth factor receptor 1 (FGFR1),bcl 2 and caspase 3. Methods (2000? 500) lx cold white light was used. Exogenous bFGF was utilized during culture. Annexin annexin V fluorescein isothiocyanate/propidium iodium (V FITC/PI) labeling,flow cytometry, Immunocytochemical staining, enzyme associated absorb examing and reverse transcriptional polymerase chain reaction (RT PCR) were used to determine the apoptosis, the expression levels of bFGF, FGFR1, bcl 2, as well as the activity of caspase 3. Results No protective effect of bFGF was observed under the concentration 5 ng/ml. A significant inhibition of apoptosis was found in 10 ng/ml and 20 ng/ml groups ( P5 ng/ml) groups than light exposure groups ( P

Objective To investigate the detection of human bocavirus (HBoV) in children with acute respiratory infection and to explore the relationship between viral load and clinical characteristics of acute respiratory infection in children.Methods A total of 4 501 nasopharyngeal secretion samples were collected from hospitalized children with acute respiratory infection from January 2013 to June 2013.HBoV-positive children were divided into simple infection group and mixed infection group.Children with HBoV DNA≥1 × 104 copy/mL were categorized into high viral load group,while those with HBoV DNA ＜1 × 104 copy/mL were categorized into low viral load group.HBoV was determined by fluorescence quantitative polymerase chain reaction (PCR).Respiratory syncytial virus (RSV),influenza virus (Inf)-A,Inf-B,parainfluenza virus (Pinf)-Ⅰ 、Pinf-Ⅱ 、Pinf-Ⅲ and adeno virus antigen were detected by direct antigen-specific immunofluorescence assays.Mycoplasm Pnuemonia was detected by real-time fluorescence quantitative PCR.Serum mycoplasma antibodies were detected by enzyme-linked immunosorbent assay (ELISA).Bacteria was detected by sputum culture.Over the same period,23 children undergoing elective inguinal hernia operation with no respiratory infection or fever were considered as control group.The percentage of peripheral blood T lymphocyte subsets were tested by flow cytometry.Inter-group differences were compared using Chi-square test or Fisher exact test.Viral loads were compared using Mann-Whitney test.Results Two hundred and twenty-two HBoV-positive cases were detected with a positive rate of 5.41％ (222/4 105),33.33％ (74/222) of which were with high viral load and 66.67％ (148/222) were with low viral load.There was a high incidence in the age group of 1-2 years.The simple HBoV infection accounted for 24.32％,including 26 cases with high viral load and 28 cases with low viral load.Wheezing was more common in patients with high viral load than those with low viral load,and the difference was statistically significant (88.46 ％ vs 42.86 ％,x2 =12.295,P=0.001).Among the 222 HBoV-positive cases,the median viral load of HBoV in simple infection group was 3.86 × 103 copy/mL,and 1.0× 103 copy/mL in mixed infection group.The difference of the viral load between these two groups was statistically significant (Z =2.906,P =0.004).Mycoplasma and Streptococcus pneumonia were most commonly detected in the 168 patients with mixed infection.Percentages of CD3+ and CD3+/CD8+ subsets were significantly lower in HBoV simple infection group and mixed infection group,compared to control group (both P＜0.05).However,percentages of CD3 /CD19+,CD19+/ CD23+ subsets were significantly higher in HBoV simple infection group and mixed infection group,compared to control group (both P＜0.05).Conclusions HBoV is one of the pathogens causing acute respiratory tract infection in children,which lead to cellular immunity dysfunction in children.Moreover,children with higher HBoV load are more likely to develop wheezing.Co-infection with other pathogens should be considered in children with low HBoV load.

Objective To study the association between activity of hand,foot and mouth disease (HFMD) and the meteorological factors in Suzhou.Methods A total of 17 653 children diagnosed with HFMD in Children's Hospital Affiliated to Suzhou University during 2008 to 2011 were enrolled.The meteorological factors in(c)luding mean temperature,relative humidity,rainfall amount,sum of sunshine and mean wind velocity during Jan 2008 to Dec 2011 were collected monthly.Numeration data were analyzed using chi square or Fisher exact test.Normal distribution data were analyzed using Pearson correlation and non-normal distribution data were analyzed using Spearman rank correlation.Results HFMD could be found all over the year and had obvious seasonality which peaked in Summer,followed by Spring and Autumn and HFMD decreased markedly in Winter.The activity of HFMD was positive correlated with mean temperature(r=0.716,P＜0.01),wind velocity (r=0.630,P＜0.01),rainfall(r=0.477,P＜0.01) and sum of sunshine(r=0.311,P＜0.05).No statistical significance was observed between relative humidity and HFMD(r =0.276,P＞0.05).Multivariate stepwise regression analysis showed that only mean temperature and rainfall were associated with HFMD and mean temperature had stronger influence on HFMD than rainfall (t =4.687,P ＜ 0.01 ; t =2.258,P ＜ 0.05).Conclusions HFMD has obvious seasonality.Mean temperature and rainfall are the main factors affecting this seasonality.

Asthma ; genetics ; Child ; Child, Preschool ; Gene Frequency ; Genotype ; Humans ; Infant ; Male ; Peptidyl-Dipeptidase A ; genetics ; Polymerase Chain Reaction ; Polymorphism, Genetic

Objective To study the epidemiological and clinical features of human parainfluenza virus (HPIV) infection in children in Suzhou,and to provide the evidence-based foundation for early warning,diagnosis and treatment of respiratory infection in children.Methods The sputum specimens and medical history were obtained from children with acute respiratory tract infection hospitalized at the Childen's Hospital Affiliated to Soochow University from January 2006 to December 2015.Seven kinds of common respiratory viruses including respiratory syncytial virus,influenza virus A,influenza virus B,HPIV Ⅰ,HPIV Ⅱ,HPⅣV Ⅲ and adenovirus were detected by using the direct im-munofluorescence.Mycoplasma pneumoniae(MP),chlamydia pneumoniae,human bocavirns (hBoV) were detected by using fluorescence quantitative PCR.Rhinovirus and human metapneumovirus were detected by using reverse transcription-PCR.Sputum was cultured for bacteria.Results In 21 769 cases,the detection rate of HPIV positive was 3.21％ (829 cases),among which,HPIV Ⅰ,HPIV Ⅱ,HPIV Ⅲ were respectively detected in 113 cases (0.52％),16 cases (0.07 ％) and 700 cases (3.21％),respectively.There were 378 cases of simple infection and 428 cases of mixed infection,and the mixed infection was very common in Streptococcus pneumoniae,Haemophilus influenza,MP and hBoV.There was a difference in HPIV infection among genders,and the detection rate of the boys was higher than that of girls[4.14％ (563/13 591 cases) vs.3.25％ (266/8 178 cases),x2 =11.036,P =0.001].In the 28 d-1 year old and ＞ 1-3 year old group,the detection rate of HPIV was higher[4.71％ (494/10 476 cases) and 4.21％ (244/5 793 cases),respectively].In spring and summer,there was a higher detection rate of HPIV infection.The clinical manifestations with simple infection of HPIV Ⅰ and HPIV Ⅲ were cough,fever and wheezing.The rate of fever and shortness of breath in those of HPIV Ⅰ was 71.74％ (33/46 cases),10.87％ (5/46 cases),and that in HPIV Ⅲ was 40.12％ (134/334 cases),2.10％ (7/334 cases),HPIV Ⅰ infection was more likely to cause fever and shortness of breath than those of HPIV Ⅲ,there were significant differences (x2 =16.410,P ＜ 0.001;x2 =10.177,P =0.001).Pneumonia had the highest detection rate of viral infection.Conclusions HPIV Ⅲ is the leading pathogen among the types of HPIV in the hospitalized children in Suzhou area.Among the subtypes of HPIV,the peak of HPIV infection occurs in spring and summer.The children less than 3 years old are the most susceptible to parainfluenza virus,and the HPIV detection rate is gradually declines with age.

Objective To explore the correlation of meteorological parameters with the epidemic of acute Moraxella ca-tarrhalis respiratory infection in hospitalized children in Suzhou. Methods A total of 8143 children with acute respiratory infec-tion were participated in the trial during 2006 to 2010, and the secretions of nasopharynx were collected for bacterium culture. Moraxella catarrhalis was identified according to the routine technique of culture. Meteorological parameters including mean temperature, relative humidity, rainfall amount, duration of sunshine and mean wind velocity were collected monthly during the same period. The relationship between the epidemic of Moraxella catarrhalis and metrorological parameters were analyzed by seasonal decomposition method, the Spearman rank correlation and stepwise regression analysis. Results Moraxella catarrhalis was identified in 4.04% of 8 143 specimens. The prevalence of acute Moraxella catarrhalis respiratory infection was higher during winter and spring. The monthly infection rate of Moraxella catarrhalis was negatively correlated with mean temperature as well as duration of sunshine and wind velocity. Wind velocity was independent risk factor for Moraxella catarrhalis infection. Conclusions Moraxella catarrhalis is a primary pathogen in respiratory tract infection in children in Suzhou. The epidemic of Moraxella catarrhalis is closely related to meteorological parameters.

Objective To discuss the pulmonary function change in infants with human bocavirus (HBoV) pneumonia or mycoplasma pneumonia (MP) and its clinical signiifcance. Methods One hundred and forty infants under 3 years old who were admitted due to pulmonary infection were recruited from January, 2013 to October, 2013. Among them, HBoV-DNA was detected in 64 cases, and MP-DNA was detected in 76 cases. Thirty eight normal age-matched infants were selected as controls. The shape of tidal breathing lfow-volume loops (TBFVLs) and change of every index were measured with a Pulmonary Testing System (Jaeger MasterScope). Results The ratio of time to peak tidal expiratory lfow (PTEF) to total expiratory time (TPTEF/TE), the ratio of VPTEF to expiratory volume (VPTEF/VE), tidal expiratory lfow at 25%of the remaining tidal volume (TEF25%) and the ratio of TEF25%to PTEF (25/PF) were signiifcantly decreased in infants with HBoV and MP infection as compared with healthy infants (P<0.05). However, there was no signiifcant difference of the above indices between infants with HBoV and MP infection (P>0.05). The shape of TBFVLs in infants with HBoV and MP pneumonia was changed and characterized by left-shifted PTEF and trough-like concave in descending limb. The PTEF was decreased in infants with pulmonary infection. Conclusions HBoV or MP infection results in impaired pulmonary function with manifestations of obstruction in small airway. The shape of TBFVLs in infants with HBoV and MP pneumonia is characterized by left-shifted PTEF and trough-like concave in descending limb.

Objectives To explore the effects of nasopharyngeal bacterial colonization in children with acute bronchiolitis due to respiratory syncytial virus (RSV).Methods Hospitalized children of acute bronchiolitis were enrolled to detect pathogen and bacterial colonization.Their clinical data and laboratory results were collected and analyzed.Cases of elective surgery were also obtained as control group.Results Fifty-five percent of all children with bronchiolitis had a lower positive rate of nasopharyngeal bacterial culture (55.0％ vs.74.1％,P ＜0.01).Children with nasopharyngeal bacterial colonization had a higher rate of severe bronchiolitis (13.8％ vs.4.2％,P =0.018),presented dyspnea more frequently (19.8％ vs.9.5％,P =0.037) and had a longer hospital duration (8.2 vs.7.5 days,P =0.036) as compared with those without bacterial colonization.In terms of laboratory results,a higher proportion of C-reactive protein was found in children with bacterial colonization than those with non-bacterial colonizations (17.2％ vs.4.2％,P =0.003).Conclusion Bacterial colonization may be a predictor for severe bronchiolitis.