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Tzou Yien Lin - One of the best experts on this subject based on the ideXlab platform.
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Chlamydial Pneumonia in children requiring hospitalization effect of mixed infection on clinical outcome
Journal of Microbiology Immunology and Infection, 2005Co-Authors: Minghan Tsai, Yhu Chering Huang, Chihjung Chen, Pen Yi Lin, Luanyin Chang, Chenghsun Chiu, Kuo Chien Tsao, Chung Guei Huang, Tzou Yien LinAbstract:The etiology of community-acquired Pneumonia (CAP) in a children's hospital was studied among 209 previously healthy children treated from August 1, 2001 to July 31, 2002. A total of 26 children (12.4%) with a diagnosis of Chlamydial infection were included in this study. The diagnosis of Chlamydial infection was based on either a positive immunofluorescent assay result for Chlamydial antigen in sputum, or positive serologic results for immunoglobulin M (IgM), an IgG titer >/=1:640 or a 4-fold rise in IgG titer by microimmunofluorescence test. Fourteen patients (53.8%) were female and 20 (76.9%) were less than 5 years of age. The onset of infection occurred between August and January in 21 cases (80.7%). Twenty one patients (80.8%) had other pathogens identified. Fever and cough were the most common presenting symptoms. The signs and symptoms were similar for the children with and without coinfection except for tachypnea and wheezing sound, which were significantly more common in patients with mixed infection. None of the laboratory parameters seemed to be specific for Chlamydial infection; however, serum C-reactive protein level was significantly higher in cases with mixed infection. Among the 26 children, 12 (46.2%) needed respiratory therapy, and most of them (91.7%, 11/12) had coinfection. Two patients (7.7%) with mixed infection were admitted to the pediatric intensive care unit. One had lobar Pneumonia with pleural effusion and the other had necrotizing Pneumonia requiring surgical intervention. None of the patients died. In conclusion, Chlamydia sp. was identified in 12.4% of children with CAP in this series, and mixed infections were common (80.8%) among these patients. The clinical course of Chlamydial Pneumonia was not serious in most patients, but alertness is needed to the possibility of developing severe Pneumonia in cases with bacterial coinfection.
Margaret R. Hammerschlag - One of the best experts on this subject based on the ideXlab platform.
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Neonatal prophylaxis with antibiotic containing ointments does not reduce incidence of Chlamydial conjunctivitis in newborns
BMC Infectious Diseases, 2021Co-Authors: Tamar A. Smith-norowitz, Crystal Ukaegbu, Stephan Kohlhoff, Margaret R. HammerschlagAbstract:Background Neonatal ocular prophylaxis with silver nitrate does not prevent neonatal conjunctivitis due to Chlamydia trachomatis . The efficacy of antibiotic containing preparations for prevention of neonatal Chlamydial conjunctivitis (NCC) has not been established. Objective To examine published literature to determine whether antibiotic containing preparation are efficacious for prevention of NCC and C. trachomatis in the nasopharynx. Methods A literature search of MEDLINE and EMBASE. Articles were selected for review if their content included 4 key criteria: (1) Prospective/comparative study. (2) Prenatal screening of mothers for C. trachomatis with results reported. (3) Follow-up of infants born to chlamydia-positive women. (4) Infants prospectively followed at regular intervals and tested for C. trachomatis in the eye/ nasopharynx (NP). Results The search yielded 159 studies; 11 were selected for full reviews, eight were excluded; three addressed the four criteria. Rates of C. trachomatis conjunctivitis in infants in included studies who received silver nitrate was 20–33%; positive NP, 1–28% and Pneumonia, 3–8%. Rates of C. trachomatis conjunctivitis in neonates who received erythromycin or tetracycline prophylaxis did not differ from silver nitrate; 0–15 and 11%, respectively, who received erythromycin or tetracycline developed NCC. Similarly, 4–33 and 5% of infants who received erythromycin or tetracycline, respectively, had positive NP cultures; 0–4% developed Chlamydial Pneumonia. Conclusion Neonatal ocular prophylaxis with erythromycin or tetracycline ophthalmic ointments does not reduce incidence of neonatal Chlamydial conjunctivitis or respiratory infection in infants born to mothers with C. trachomatis infection compared to silver nitrate.
Guangming Zhong - One of the best experts on this subject based on the ideXlab platform.
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neonatal Chlamydial Pneumonia induces altered respiratory structure and function lasting into adult life
Laboratory Investigation, 2011Co-Authors: Madhulika Jupelli, Ashlesh K Murthy, Bharat Kumar Reddy Chaganty, Neal M Guentzel, Dale M Selby, Margarita M Vasquez, Shamimunisa B Mustafa, B M Henson, Steven R Seidner, Guangming ZhongAbstract:Respiratory dysfunction in adults has been correlated with neonatal Chlamydia trachomatis Pneumonia in several studies, but a causal association has not been clearly demonstrated. In this study, we examined radial alveolar counts (RACs) by microscopy, and airway and parenchymal lung function using a small animal ventilator in juvenile (5 weeks age) and adult (8 weeks age) BALB/c mice challenged as neonates with Chlamydia muridarum (C. mur) on day 1 or day 7 after birth, representing saccular (human pre-term neonates) and alveolar (human term neonates) stages of lung development, respectively. Pups challenged with C. mur on either day 1 or 7 after birth demonstrated significantly enhanced airway hyperreactivity and lung compliance, both as juveniles (5 weeks age) and adults (8 weeks age), compared with mock-challenged mice. Moreover, mice challenged neonatally with Chlamydia displayed significantly reduced RACs, suggesting emphysematous changes. Antimicrobial treatment during the neonatal infection induced early bacterial clearance and partially ameliorated the Chlamydia-induced lung dysfunction as adults. These results suggest that neonatal Chlamydial Pneumonia, especially in pre-term neonates, is a cause of respiratory dysfunction continuing into adulthood, and that antimicrobial administration may be partially effective in preventing the adverse respiratory sequelae in adulthood. The results of our studies also emphasize the importance of prenatal screening and treatment of pregnant women for C. trachomatis in order to prevent the infection of neonates.
Xi Yang - One of the best experts on this subject based on the ideXlab platform.
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Natural Killer T Cells Are Critical for Dendritic Cells to Induce Immunity in Chlamydial Pneumonia
2013Co-Authors: Antony George Joyee, Hongyu Qiu, Yijun Fan, Shuhe Wang, Xi YangAbstract:Rationale: We previously showed an important role of natural killer T cells (NKT) in skewing the adaptive T cell immunity to Chlamydia Pneumoniae (Cpn), an intracellular bacterial lung infection, but the mechanism remains unclear. Objectives: To investigate the underlying mechanism by which NKT modulate T cell responses in Chlamydial Pneumonia. Methods: We examined the effect of NKT activation in modulating DC function, especially in generating protective immunity against Cpn infection using combination of NKT knockout (KO) mice and specific NKT activation approaches. Measurements and Main Results: We found that NKT activation in vivo after Cpn infection induces phenotypic and functional changes in dendritic cells (DC). DC from NKT-deficient mice showed reduced CD40 expression and IL-12 production, whereas enhancing NKT activation using a-GalCer increased CD40 expression and IL-12 production. Co-culture of DC with NKT enhanced bioactive IL-12p70 production by DC in a CD40L-, IFN-g–, and cell–cell contact– dependent manner. Further, co-culture of T cells with DC isolated from infected wild-type (WT) and NKT-deficient mice induced type-1 and type-2 responses, respectively, while DC from a-GalCer– treated, infected mice led to enhanced type-1 responses. Moreover, upon adoptive transfer, DC from infected WT mice induced strong type-1 immunity, whereas those from knockout mice induced type-2 responses and increased disease severity upon challenge infection. Conclusions: Our results provide direct evidence of the critical role of NKT activation in the functional modulation of DC for the development of protective immunity in a clinically relevant respiratory infection
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natural killer t cells are critical for dendritic cells to induce immunity in Chlamydial Pneumonia
American Journal of Respiratory and Critical Care Medicine, 2008Co-Authors: Antony George Joyee, Hongyu Qiu, Yijun Fan, Shuhe Wang, Xi YangAbstract:Rationale: We previously showed an important role of natural killer T cells (NKT) in skewing the adaptive T cell immunity to Chlamydia Pneumoniae (Cpn), an intracellular bacterial lung infection, but the mechanism remains unclear.Objectives: To investigate the underlying mechanism by which NKT modulate T cell responses in Chlamydial Pneumonia.Methods: We examined the effect of NKT activation in modulating DC function, especially in generating protective immunity against Cpn infection using combination of NKT knockout (KO) mice and specific NKT activation approaches.Measurements and Main Results: We found that NKT activation in vivo after Cpn infection induces phenotypic and functional changes in dendritic cells (DC). DC from NKT-deficient mice showed reduced CD40 expression and IL-12 production, whereas enhancing NKT activation using α-GalCer increased CD40 expression and IL-12 production. Co-culture of DC with NKT enhanced bioactive IL-12p70 production by DC in a CD40L-, IFN-γ–, and cell–cell contact–dep...
Jia Tianjun - One of the best experts on this subject based on the ideXlab platform.
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Localization and bioinformatics analysis of Chlamydial Pneumonia hypothetical protein cpn0146
Journal of Clinical Hematology, 2010Co-Authors: Jia TianjunAbstract:Objective:To perform localization and bioinformatics analysis on Chlamydial Pneumonia hypothetical protein cpn0146.Method:Cpn0146 was amplified from Chlamydia Pneumonia AR39 genome and inserted to vector pGEX-6P2 to recombine expression plasmid pGEX-6P2-cpn0146.Then E.Coli XL-blue transformed with pGEX-6P2-cpn 0146 was induced with IPTG to express fusion protein GST-cpn0146.The purified GST-CPN0146 was used to immunize mice and indirect immunofluorescence assay(IFA)was adopted to carry out localization analysis of cpn0146.Finally bioinformatics analysis of Chlamydial Pneumonia hypothetical protein cpn0146s was performed with software Expasy and antheprot 5.0..Result:pGEX-6P2-cpn0146 was constructed successfully and anti-Cpn0146 polyclonal antibody was made successfully.The hypothetical protein Cpn0146 was demonstrated to locate in the inclusion membrane of Chlamydia Pneumonia using IFA.Furthermore,bioinformatics analysis showed Cpn0146 had good hydrophobicity and antigenicity.Conclusion:Chlamydial Pneumonia hypothetical protein cpn0146 was an inclusion membrane protein and had good hydrophobicity and antigenicity.
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gene cloning and expressing of Chlamydial Pneumonia cpn0147 and endogenous localization and bioinformatics analysis of its recombinant protein
Journal of Pathogen Biology, 2009Co-Authors: Tong Wei, Zhang Zhanjun, Jia TianjunAbstract:Objective To clone and express Chlamydial Pneumonia gene Cpn0147,to study its endogenous localization,and to perform bioinformatics analysis.Methods The open reading frame coding for Cpn0147 in the C.Pneumonia AR39 genome was cloned into the PGEX-6P2 vector after it was cloned using PCR and digested by the restriction enzymes BamHⅠand NotⅠ.The recombinant plasmid PGEX6P2-Cpn0147 was transformed into XL-blue bacteria and the gene Cpn0147 was expressed as fusion proteins with the GST tagged to the N-terminus.The GST-Cpn0147 fusion protein was used to immunize mice and the mouse anti-fusion protein antibody was used to localize the endogenous Cpn0147 protein in Chlamydia-infect cells using a direct immunofluorescence assay(IFA).The recombinant protein was analyzed using Expasy software.Results The Cpn0147gene,which was 450 bp in length and encoded a protein with molecular weight of 14.727 ku,was successfully cloned and the GST fusion protein with molecular weight of 43 ku was expressed.The hypothetical protein Cpn0147 was found to be located in the inclusion membrane of C.Pneumonia-infected cells using IFA.Its structure and function was indicated preliminarily by bioinformatics analysis.Conclusion The protein expressed by gene Cpn0147 was an Inc protein with good hydrophilicity and antigenicity.