Response to a Respiratory Survey

Respondents to a respiratory survey of Berlin, New Hampshire, residents in 1961 have been studied to assess the relationship between co-operation and respiratory disease prevalence. Two hundred and forty-three unco-operative subjects, interviewed at home, had significantly more morning phlegm and a lower vital capacity than carefully matched subjects who attended the central clinic. Fifty-one volunteers had the same prevalence of respiratory disease symptoms and physiological abnormalities as carefully matched subjects drawn from a probability sample of the city.It is concluded that respiratory disease prevalence will be underestimated if calculated from studies of co-operative subjects who attend a clinic. Case-finding by respiratory disease screening clinics will also miss many persons who suffer from chronic bronchitis.     

Establishing a Liquid-covered Culture of Polarized Human Airway Epithelial Calu-3 Cells to Study Host Cell Response to Respiratory Pathogens In vitro

The apical and basolateral surfaces of airway epithelial cells demonstrate directional responses to pathogen exposure in vivo. Thus, ideal in vitro models for examining cellular responses to respiratory pathogens polarize, forming apical and basolateral surfaces. One such model is differentiated normal human bronchial epithelial cells (NHBE). However, this system requires lung tissue samples, expertise isolating and culturing epithelial cells from tissue, and time to generate an air-liquid interface culture.Calu-3 cells, derived from a human bronchial adenocarcinoma, are an alternative model for examining the response of proximal airway epithelial cells to respiratory insult¹, pharmacological compounds^2-6, and bacterial^7-9 and viral pathogens, including influenza virus, rhinovirus and severe acute respiratory syndrome - associated coronavirus^10-14. Recently, we demonstrated that Calu-3 cells are susceptible to respiratory syncytial virus (RSV) infection in a manner consistent with NHBE^15,16 . Here, we detail the establishment of a polarized, liquid-covered culture (LCC) of Calu-3 cells, focusing on the technical details of growing and culturing Calu-3 cells, maintaining cells that have been cultured into LCC, and we present the method for performing respiratory virus infection of polarized Calu-3 cells.To consistently obtain polarized Calu-3 LCC, Calu-3 cells must be carefully subcultured before culturing in Transwell inserts. Calu-3 monolayer cultures should remain below 90% confluence, should be subcultured fewer than 10 times from frozen stock, and should regularly be supplied with fresh medium. Once cultured in Transwells, Calu-3 LCC must be handled with care. Irregular media changes and mechanical or physical disruption of the cell layers or plates negatively impact polarization for several hours or days. Polarization is monitored by evaluating trans-epithelial electrical resistance (TEER) and is verified by evaluating the passive equilibration of sodium fluorescein between the apical and basolateral compartments^17,18 . Once TEER plateaus at or above 1,000 Ω×cm², Calu-3 LCC are ready to use to examine cellular responses to respiratory pathogens.     

Defense Response to Pathogens Through Epigenetic Regulation in Rice

Epigenetic factors have recently emerged as key regulators of the defense response to pathogens in plants. The epigenetic mechanisms underlying defense regulation have been investigated mostly in Arabidopsis, while our understanding of the epigenetic regulation of defense in rice is limited. In this review, we summarize recent findings surrounding epigenetic mechanisms for defense in rice, primarily focusing on DNA methylation, histone modification, and small RNA regulation. In particular, we focused on RNA-directed DNA methylation (RdDM) and other epigenetic regulatory mechanisms that are involved in disease resistance. Finally, we explored potential epigenetic factors that might regulate the defense response in rice by analyzing available microarray data that can be used to uncover details of epigenetics regulation.     

Neutrophil Response to Pseudomonas aeruginosa in Respiratory Infection

Sputum from patients with acute exacerbation of respiratory infection by Pseudomonas aeruginosa was observed under the electron microscope. External to the cell wall of P. aeruginosa a granular, electron-dense material was observed which is suggestive of capsule. It is supposed that stabilization of capsule occurred by the host antibody, which was produced due to chronic infection by P. aeruginosa. Mucoid type of microcolonies were observed with a fibrous matrix of exopolysaccharide. Other types of microcolonies were surrounded by granular substances or fine fibers. Neutrophil was found to be partially surrounding the microcolony in an attempt to defense. Debris was formed mainly by the destruction of the neutrophil. Most neutrophils were found full of phagocytosed debris; in contrast only a few neutrophils were found to have phagocytosed P. aeruginosa. This study concludes that instead of phagocytosing bacteria, neutrophil phagocytosed debris and bacteria were not completely eradicated. Therefore, this might be one of the factors in the pathogenesis of respiratory infection and persistent colonization by P. aeruginosa.     

Respiratory Response to Periodic Emergence in Intertidal Molluscs

SYNOPSIS: The ratio of aerial: aquatic was computed for species of intertidal molluscs.This ratio was <1 for sub- and lower littoral species suggestingpartial anaerobiosis in air and >1 for high littoral archeogastropodssuggesting high metabolic demands in air. ratios were near unity for meso- and neogastropodspecies regardless of zonation. Littoral fringe mesogastropodshad ratios <1 reflecting reduced activity on emergence. Amajor gastropod adaptation to increasing emergence is reductionof ctenidium surface area and formation of a mantle cavity lung.Mid- and high littoral pulmonates with both a mantle cavitylung and secondary gills have ratios near unity. In contrast, littoral fringe pulmonates withoutsecondary gills are partially anaerobic in water. Emerged lowand mid-littoral bivalves close the valves, are almost entirelyanaerobic, have ratios 0.14:1and conserve energy by greatly reducing metabolic demand inair. In contrast, emerged high littoral bivalves remain aerobicby periodic gaping and mantle cavity ventilation. Such behaviorssupport an aerobic metabolism while minimizing evaporative waterloss. Aerial gas exchange prevents anaerobic end-product accumulationand, with a reduction in energy demand, allows efficient energystore utilization during prolonged emergence.     

Cell-mediated Immune Response in Primary Biliary Cirrhosis to a Protein Fraction from Human Bile

Cell-mediated immune responses to a protein fraction of human bile have been demonstrated, using the leucocyte migration test, in eight out of 10 patients with primary biliary cirrhosis but in only three out of nine with active chronic hepatitis. In the latter condition sensitization to a liver-specific hepatocellular antigen was found more frequently (five out of nine patients) than in primary biliary cirrhosis (two out of 10). These results, as well as the granuloma formation observed histologically, suggest that the initial bile duct lesion in primary biliary cirrhosis may be associated with a cell-mediated response to antigens—perhaps derived from bile duct epithelial cells—which may be normal constituents of hepatic bile.     

Neutrophil Response to Nontypable Haemophilus influenzae in Respiratory Infections

Sputa from patients with respiratory infections by nontypable Haemophilus influenzae (H. influenzae) were investigated by electron microscopy. The cell wall of H. influenzae appeared wavy and nonwavy. In the cell wall the peptidoglycan layer was ill-defined. These patients had adequate IgG response in the serum against H. influenzae. However neither capsule nor fimbriae were found. Different stages of phagocytosis and destruction of the bacteria by polymorphonuclear neutrophils (PMN) were observed. PMNs were also found to phagocytose the debris. Evidences were found that the debris is formed mainly by the destruction of polymorphonuclear neutrophil. Extracellular lysosomes were also observed, which may have a role in destruction of both bacteria and host tissue. It was concluded that nontypable H. influenzae are nonfimbriated and noncapsulated during infection. Debris are the end product of PMN destruction, and phagocytosis of debris by PMNs has a role in the pathogenesis of chronic respiratory diseases.     

Viral and Bacterial Pathogens in Bovine Respiratory Disease in Finland

Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage. Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition, 6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth of Mycoplasma dispar and Pasteurella multocida, were typical findings in diseased calves. Pasteurella sp. strains showed no resistance to tested antimicrobials. Mycoplasma bovis and Mannheimia haemolytica were not found.     

Biofilm Formation and Detachment in Gram-Negative Pathogens Is Modulated by Select Bile Acids

Biofilms are a ubiquitous feature of microbial community structure in both natural and host environments; they enhance transmission and infectivity of pathogens and provide protection from human defense mechanisms and antibiotics. However, few natural products are known that impact biofilm formation or persistence for either environmental or pathogenic bacteria. Using the combination of a novel natural products library from the fish microbiome and an image-based screen for biofilm inhibition, we describe the identification of taurine-conjugated bile acids as inhibitors of biofilm formation against both Vibrio cholerae and Pseudomonas aeruginosa. Taurocholic acid (1) was isolated from the fermentation broth of the fish microbiome-derived strain of Rhodococcus erythropolis and identified using standard NMR and MS methods. Screening of the twelve predominant human steroidal bile acid components revealed that a subset of these compounds can inhibit biofilm formation, induce detachment of preformed biofilms under static conditions, and that these compounds display distinct structure-activity relationships against V. cholerae and P. aeruginosa. Our findings highlight the significance of distinct bile acid components in the regulation of biofilm formation and dispersion in two different clinically relevant bacterial pathogens, and suggest that the bile acids, which are endogenous mammalian metabolites used to solubilize dietary fats, may also play a role in maintaining host health against bacterial infection.     

Genomic Circuitry Underlying Immunological Response to Pediatric Acute Respiratory Infection

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胆总管结石患者胆汁病原菌分布特点及耐药性分析

目的:探讨胆总管结石患者胆汁病原菌的分布特点以及耐药性的分析。方法:选择2016年6月-2017年6月期间我院收治的胆总管结石合并胆道感染患者160例为研究对象,所有患者均进行逆行内镜胰胆管造影(ERCP)并抽取胆汁标本,进行细菌培养和耐药性实验,评价分析胆汁病原菌的分布特点及耐药性情况。结果:160例患者中有117例(73.13%)检出病原菌,共培养出病原菌130株,其中有13例患者为两种病原菌同时感染。革兰阴性菌有95株(73.08%)、革兰阳性菌有31株(23.85%)、真菌有4株(3.08%)。比例由高到低的前六位病原菌依次为:大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌、屎肠球菌、铜绿假单胞菌、粪肠球菌。革兰阴性菌对亚胺培南、阿米卡星、美罗培南、他唑巴坦、头孢吡肟等三四代头孢菌素耐药率较低,对头孢曲松、环丙沙星、左氧氟沙星、哌拉西林、氨苄西林等耐药率较高。革兰阳性菌对替拉考宁、万古霉素、利奈唑胺等耐药率较低,对四环素、环丙沙星、左氧氟沙星、克林霉素、氨苄西林等耐药率较高。真菌对酮康唑、伊曲康唑、氟康唑等耐药率较低,对两性霉素B耐药率较高。结论:胆总管结石患者胆汁病原菌主要为革兰阴性菌、其次为革兰阳性菌,各病原菌对各种抗菌药物表现出不同的耐药性,因此在临床治疗时应参考药敏试验结果进行合理选择治疗药物。