• Korean Journal of Veterinary Service
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• v.27 no.2
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• pp.153-157
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• 2004

Bacteria isolated from nasal cavity of 50 Thoroughbred horses with respiratory tract infection were examined. There were isolated Pseudomonas aeruginosa(33.5%), Escherichia coli(10.2%), Pseudomonas spp(7.6%), Klebsiella oxytoca(5.9%), Streptococcus equi subsp zooepidemious(6.2%), Klebsiella pneumoniae(3.4%), Acinetobacter spp(5.5%) and coagulase negative staphylococcus(2.1%). The majority of isolates were highly susceptible to amikacin, amoxicillin, aztreonam, cefotaxime, cefepime, cefotetan, ceftazidime, cefuroxime, chloramphenicol, ciprofloxacin, clindamycin, erythromycin, gentamicin, imipenem, tetracyclin and vancomycin. These results can provide basic information for the treatments of respiratory tract infections in Thoroughbred horses.

• Pediatric Infection and Vaccine
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• v.26 no.3
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• pp.129-139
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• 2019

The human respiratory tract hosts both pathogenic and commensal bacteria. The development of well-conserved 16S rRNA sequencing and culture-independent techniques has enabled many achievements in the study of the human microbiome. Microbial composition of the respiratory tract in early childhood has been shown to correlate to respiratory health in later stages of life. This review highlights current understandings of respiratory microbiota development in healthy children, examples of microbial interactions, impacts on the host immune system, and the relationship between respiratory tract microbiome and respiratory health.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.32 no.1
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• pp.29-34
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• 2021

Background and Objectives Tracheostomy lead to persistent bacterial colonization of the respiratory tract. Surgical site infection and restenosis by the pathogenic bacteria is the most fatal complication after open airway surgery. The aim of this study is to describe the culture results of larynx and tracheostoma in patients with tracheostomy and the preoperative, intraoperative culture results in patients underwent open airway surgery. Materials and Method A retrospective review was performed on 18 patients who underwent culture between 2017 and 2019. Results Pseudomonas or antibiotic resistance bacteria were identified in 11 patients out of 18 patients (61.1%); Ceftriaxone-resistant Streptococcus (38.9%), Pseudomonas (33.3%), Methicillin-resistant Staphylococcus aureus (16.7%), extended-spectrum β-lactamases (ESBL) producing Klebsiella pneumoniae (11.1%). Among 18 patients, 6 patients showed the different culture result between larynx and tracheostoma. In 4 out of 10 patients who underwent open airway surgery, the bacteria were not identified before surgery, but the bacteria were isolated in the intraoperative culture. In one patient, the bacteria detected intraoperatively were different from those detected before surgery. Conclusion Preoperative respiratory tract culture and usage of perioperative antibiotics according to the culture are necessary. It is crucial to verify the bacterial culture in both tracheostoma and larynx. And it should be performed immediately before open airway surgery.

• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.533-542
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• 2014

We extracted essential oils from four species (Pinus densiflora, Larix kaempferi, Pinus koraiensis, and Abies holophylla) in the family Pinaceae to investigate their antibacterial activities against respiratory tract bacteria (Klebsiella pneumoniae, Haemophillus influenzae, Streptococcus pyogenes, Streptococcus pneumonia, and Neisseria meningitides). Among the tested oils, that from A. holophylla was showed strong activity based on disc diffusion and broth medium dilution (minimum inhibitory concentration, MIC) assays. Qualitative analysis of A. holophylla oil was carried out by GC-MS; ${\alpha}$-pinene, camphene, ${\beta}$-pinene, 3-carene, limonene, bornyl acetate, borneol, ${\beta}$-caryophyllene, ${\alpha}$-caryophyllene, caryophyllene oxide, and ${\alpha}$-bisabolol were identified as its major constituents. Fractionation by silica gel chromatography was performed to analyze the active constituents of the crude oil. In particular, one fraction containing caryophyllene oxide as the major constituent showed stronger antibacterial activity than the crude oil of A. holophylla. Growth rates of bacterial strains exposed to fraction D were explored by optical density (OD600) measurements while morphology was examined by optical microscopy observations ( ${\times}1000$). OD600 of K. pneumoniae decreased from 0.2582 to 0.005 in response to treatment with fraction D at a MIC value of $0.31{\mu}{\ell}/m{\ell}$.

• Tuberculosis and Respiratory Diseases
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• v.71 no.6
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• pp.476-479
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• 2011

The Streptococcus milleri group, which also includes S. anginosus, S. intermedius and S. constellatus, is found in the oropharynx, upper respiratory tract, gastrointestinal tract, and urogenital tract mucosa. Bacteria in the Streptococcus milleri group are associated with bacteremia and abscess formation. Most of the reports of of Streptococcus milleri group (SMG) infection occur in patients with underlying medical conditions. Predisposing factors that have been associated with S. milleri group empyema include mucosal disturbances (sinusitis, periodontal disease, enteric disease), preceding to pneumonia, thoracic surgery, malignancy, neurological disease, alcohol abuse, and also diabetes mellitus. We report on a 42-year-old man with mental retardation. He who suffered from dyspnea and a fever that he had developed for over 14 days. S. constellatus and anaerobic bacterias (Prevotella buccae and Micromonas micros) were cultured. The patient was treated with the drainage of pleural effusion and clindamycin and levofloxacin.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.194-204
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• 2020

The detrimental impact of air pollution as a result of frequent exposure to fine particles posed a global public health risk mainly to the pulmonary disorders in pediatric and geriatric population. Here, we reviewed the current literature regarding the role of ginseng and/or its components as antimicrobials, especially against pathogens that cause respiratory infections in animal and in vitro models. Some of the possible mechanisms for ginseng-mediated viral inhibition suggested are improvements in systemic and mucosa-specific antibody responses, serum hemagglutinin inhibition, lymphocyte proliferation, cell survival rate, and viral clearance in the lungs. In addition, ginseng reduces the expression levels of proinflammatory cytokines (IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-6, IL-8) and chemokines produced by airway epithelial cells and macrophages, thus preventing weight loss. In case of bacterial infections, ginseng acts by alleviating inflammatory cytokine production, increasing survival rates, and activating phagocytes and natural killer cells. In addition, ginseng inhibits biofilm formation and induces the dispersion and dissolution of mature biofilms. Most clinical trials revealed that ginseng, at various dosages, is a safe and effective method of seasonal prophylaxis, relieving the symptoms and reducing the risk and duration of colds and flu. Taken together, these findings support the efficacy of ginseng as a therapeutic and prophylactic agent for respiratory infections.

• Clinical and Experimental Pediatrics
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• v.64 no.11
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• pp.543-551
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• 2021

The human microbiome, which consists of a collective cluster of commensal, symbiotic, and pathogenic microorganisms living in the human body, plays a key role in host health and immunity. The human nasal cavity harbors commensal bacteria that suppress the colonization of opportunistic pathogens. However, dysbiosis of the nasal microbial community is associated with many diseases, such as acute respiratory infections including otitis media, sinusitis and bronchitis and allergic respiratory diseases including asthma. The nasopharyngeal acquisition of pneumococcus, which exists as a pathobiont in the nasal cavity, is the initial step in virtually all pneumococcal diseases. Although the factors influencing nasal colonization and elimination are not fully understood, the adhesion of opportunistic pathogens to nasopharyngeal mucosa receptors and the eliciting of immune responses in the host are implicated in addition to bacterial microbiota properties and colonization resistance dynamics. Probiotics or synbiotic interventions may show promising and effective roles in the adjunctive treatment of dysbiosis; however, more studies are needed to characterize how these interventions can be applied in clinical practice in the future.

• Tuberculosis and Respiratory Diseases
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• v.74 no.2
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• pp.63-69
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• 2013

Background: Aiming to improve outcome of lung transplantation (LTx) patients, we reviewed risk factors and treatment practices for the LTx recipients who experienced respiratory infection in the late post-LTx period (>1 month after LTx). Methods: We analyzed the clinical data of 48 recipients and donors from 61 LTx, who experienced late respiratory infections. Late respiratory infections were classified according to the etiology, time of occurrence, and frequency of donor-to-host transmission or colonization of the recipient prior to transplantation. Results: During the period of observation, 42 episodes of respiratory infections occurred. The organisms most frequently involved were gram (-) bacteria: Acinetobacter baumannii (n=13, 31.0%), Pseudomonas aeruginosa (n=7, 16.7%), and Klebsiella pneumoniae (n=4, 10.0%). Among the 42 episodes recorded, 14 occurred in the late post-LTx period. These were bacterial (n=6, 42.9%), fungal (n=2, 14.3%), viral (n=4, 28.5%), and mycobacterial (n=2, 14.3%) infections. Of 6 bacterial infections, 2 were from multidrug-resistant (MDR) A. baumannii and one from each of MDR P. aeruginosa, extended spectrum ${\beta}$-lactamase (+) K. pneumoniae, methicillin-resistant Staphylococcus aureus and Streptococcus pneumoniae. Infection-related death occurred in 6 of the 14 episodes (43%). Conclusion: Although the frequency of respiratory infection decreased sharply in the late post-LTx period, respiratory infection was still a major cause of mortality. Gram (-) MDR bacteria were the agents most commonly identified in these infections.

• Safety and Health at Work
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• v.1 no.2
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• pp.183-191
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• 2010

Objectives: The objective of this study is to investigate the distribution patterns and exposure concentrations of bioaerosols in industries suspected to have high levels of bioaerosol exposure. Methods: We selected 11 plants including 3 livestock feed plants (LF industry), 3 metal working fluids handling plants (MWFs industry), and 5 sawmills and measured total airborne bacteria, fungi, endotoxins, as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage cascade impactor, and gelatin filters. Endotoxins were measured with polycarbonate filters. Results: The geometric means (GM) of the airborne concentrations of bacteria, fungi, and endotoxins were 1,864, $2,252\;CFU/m^3$, and $31.5\;EU/m^3$, respectively at the sawmills, followed by the LF industry (535, $585\;CFU/m^3$, and $22.0\;EU/m^3$) and MWFs industry (258, $331\;CFU/m^3$, and $8.7\;EU/m^3$). These concentrations by industry type were significantly statistically different (p < 0.01). The ratio of indoor to outdoor concentration was 6.2, 1.9, 3.2, and 3.2 for bacteria, fungi, endotoxins, and dust in the LF industry, 5.0, 0.9, 2.3, and 12.5 in the MWFs industry, and 3.7, 4.1, 3.3, and 9.7 in sawmills. The respiratory fractions of bioaerosols were differentiated by bioaerosol types and industry types: the respiratory fraction of bacteria in the LF industry, MWF industry, and sawmills was 59.4%, 72.0%, and 57.7%, respectively, and that of fungi was 77.3%, 89.5%, and 83.7% in the same order. Conclusion: We found that bioaerosol concentration was the highest in sawmills, followed by LF industry facilities and MWFs industry facilities. The indoor/outdoor ratio of microorganisms was larger than 1 and respiratory fraction of microorganisms was more than 50% of the total microorganism concentrations which might penetrate respiratory tract easily. All these findings suggest that bioaerosol in the surveyed industries should be controlled to prevent worker respiratory diseases.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1109-1114
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• 2021

Chlamydia pneumoniae is a type of pathogenic gram-negative bacteria that causes various respiratory tract infections including asthma. Chlamydia species infect humans and cause respiratory infection by rupturing the lining of the respiratory which includes the throat, lungs and windpipe. Meanwhile, the function of interleukin-4 (IL-4) in Ch. pneumoniae respiratory infection and its association with the development of airway hyperresponsiveness (AHR) in adulthood and causing allergic airway disease (AAD) are not understood properly. We therefore investigated the role of IL-4 in respiratory infection and allergy caused by early life Chlamydia infection. In this study, Ch. pneumonia strain was propagated and cultured in HEp-2 cells according to standard protocol and infant C57BL/6 mice around 3-4 weeks old were infected to study the role of IL-4 in respiratory infection and allergy caused by early life Chlamydia infection. We observed that IL-4 is linked with Chlamydia respiratory infection and its absence lowers respiratory infection. IL-4R α2 is also responsible for controlling the IL-4 signaling pathway and averts the progression of infection and inflammation. Furthermore, the IL-4 signaling pathway also influences infection-induced AHR and aids in increasing AAD severity. STAT6 also promotes respiratory infection caused by Ch. pneumoniae and further enhanced its downstream process. Our study concluded that IL-4 is a potential target for preventing infection-induced AHR and severe asthma.