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The association of air pollution and greenspace with respiratory pathogen acquisition and respiratory health was investigated in a community-based birth-cohort of 158 Australian children. Weekly nasal swabs and daily symptom-diaries were collected for 2-years, with annual reviews from ages 3-7-years. Annual exposure to fine-particulate-matter (PM2.5), nitrogen-dioxide (NO2), and normalised-difference-vegetation-index (NDVI) was estimated for pregnancy and the first 2-years-of-life. We examined rhinovirus, any respiratory virus, Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae detections in the first 3-months-of-life, age at initial pathogen detection, wheezing in the first 2-years, and asthma at ages 5-7-years. Our findings suggest that higher NDVI was associated with fewer viral and M. catarrhalis detections in the first 3-months, while increased PM2.5 and NO2 were linked to earlier symptomatic rhinovirus and H. influenzae detections, respectively. However, no associations were observed with wheezing or asthma. Early-life exposure to air pollution and greenspace may influence early-life respiratory pathogen acquisition and illness. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the difference between the bacterial profiles of the nasal cavities and adenoid surfaces of children with chronic rhinosinusitis (CRS). We also intended to determine and analyze the potential correlation between the pre- and post-adenoidectomy differences in the nasal bacterial profile and clinical prognosis. Methods: The clinical information of pediatric patients was collected. All the children underwent adenoidectomy (with or without tonsillectomy), and swab samples were collected during the operation. Visual analog scales (VAS) were used at 3, 6, and 12 months postoperatively. At the 12-month follow-up examination, swab samples were collected again. PCR amplification was performed of the v3-v4 variable regions of 16S rRNA of the collected specimens, as well as high-throughput sequencing using the Illumina platform. The species information was obtained by OTUs clustering, species annotation, and α-diversity analysis. Results: Twenty-two male and eight female pediatric patients were included in the investigation The most abundant genus level bacterial representatives on the nasal surface before adenoidectomy were Moraxella catarrh, Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus, whereas on the surface of adenoids, they were Streptococcus pneumonia, Haemophilus influenza, Nucleobacter, and Moraxella catarrhalis. One year postoperatively, the bacteria with the highest abundance on the nasal surface at the genus level were Moraxella catarrhalis, Streptococcus pneumonia, Staphylococcus aureus, and non-culturable Dolosigranulum. One year postoperatively, the bacterial richness in the nasal cavity was significantly higher than at baseline (P <.05). Furthermore, the subjective nasal score of all children significantly decreased at 3, 6, and 12 months postoperatively (P <.01). Conclusion: The preoperative bacterial abundance of the nasal cavity and the adenoid surfaces was similar, showing a clear correlation. No single specific bacterium was established to be a dominant species associated with the development of CRS in children. The post-adenoidectomy bacterial richness in the nasal cavity was significantly increased, which may be closely related to the relief of postoperative sinusitis symptoms. [ABSTRACT FROM AUTHOR]

Bacteriophages were discovered in early 20th century. However, the interest in bacteriophage research was reduced with the discovery of antibiotics. With the increasing number of infections due to multidrug-resistant (MDR) organisms, the potential usefulness of bacteriophages as therapeutic agents has been re-evaluated. In this review, we found that more than 30 lytic bacteriophages that infect Acinetobacter species have been characterised. These are mainly members of Caudovirales, with genome sizes ranging from 31 kb to 234 kb and G+C contents ranging from 33.5% to 45.5%. The host range can be as low as < 10% of all tested Acinetobacter strains. Fourteen published murine trials indicated positive outcomes in bacteriophage-treated groups. Only two case reports were pertaining to the use of bacteriophages in the treatment of Acinetobacter infections in humans; in both cases, the infections were resolved with bacteriophage therapy. The use of bacteriophages has been associated with reduced Acinetobacter burden in the environment, as shown in two studies. The major limitation of bacteriophage therapy is its highly selective host strain. In conclusion, the potential usefulness of bacteriophage therapy for the treatment of MDR Acinetobacter species has been documented only in limited studies and more research is needed prior to its extensive use in clinical practice. [ABSTRACT FROM AUTHOR]

Background Streptococcus pneumoniae (Spn), Haemophilus influenzae (Hflu), and Moraxella catarrhalis (Mcat) nasopharyngeal colonization precedes disease pathogenesis and varies among settings and countries. We sought to assess colonization prevalence, density, Spn serotypes, and antibiotic resistance in children in the first 6 months of life in pediatric primary care settings. Methods Prospective cohort study in Rochester, NY during 2018–2020. Nasopharyngeal swabs were collected from 101 children at age 1, 2, and 3 weeks, then 1, 2, 4, 6, 9, 12, 15, 18, and 24 months. Spn serotypes were determined by Quellung. Oxacillin resistance for Spn and β-lactamase production by Hflu and Mcat was tested. All children received PCV13 vaccine according to U.S. recommended schedule. Results Spn, Hflu , and Mcat colonization was detected in only 5% of infants before age 2 months old. Cumulative prevalence was 34% for Spn , 10% for Hflu , and 53% for Mcat in children ≤6 months of age. Nasopharyngeal bacterial density of Spn, Hflu , and Mcat (x = 2.71 log) in children ≤6 months of age was lower than at 7–24 months of age (x = 3.15 log, p < 0.0001). Predominant serotypes detected ≤6 months of age were 23B (16.7%), 22F (12.9%), 15B/C (11%), and 16F (9.2%). In total, 14.8% of Spn isolates were oxacillin resistant and 66.7% of Hflu isolates were β-lactamase producing. Conclusion Spn, Hflu , and Mcat nasopharyngeal colonization was uncommon and of low density among children ≤6 months old, especially among children <2 months of age. Non-PCV13 serotypes predominated and a different serotype distribution was observed in ≤6-month olds compared to 7- to 24-month olds. [ABSTRACT FROM AUTHOR]

Background Pneumococcal conjugate vaccines (PCVs) effectively reduce infection and asymptomatic carriage of Streptococcus pneumoniae vaccine serotypes. In 2016, Belgium replaced its infant PCV13 program by a 4-year period of PCV10. Concomitantly, S. pneumoniae serotype carriage was monitored together with the carriage of other nasopharyngeal pathogens in children attending day-care centers. Methods From 2016 to 2019, a total of 3459 nasopharyngeal swabs were obtained from children aged 6–30 months. Culture and qPCR were used for the identification of S. pneumoniae , Haemophilus influenzae, Moraxella catarrhalis , and Staphylococcus aureus and for serotyping and antimicrobial susceptibility assessment of S. pneumoniae strains. Results S. pneumoniae colonization was frequent and stable over the study years. H. influenzae and M. catarrhalis were more frequently carried (P  < .001) than S. pneumoniae , by, respectively, 92.3% and 91.0% of children. Prevalence of all PCV13 serotypes together increased significantly over time from 5.8% to 19.6% (P  < .001) and was attributable to the increasing prevalence of serotype 19A. Coincidently, non-vaccine serotype 6C increased (P  < .001) and the overall pneumococcal non-susceptibility to tetracycline and erythromycin. Non-susceptibility to cotrimoxazole decreased (P  < .001). Conclusions The switch to a PCV program no longer covering serotypes 19A, 6A, and 3 was associated with a sustained increase of serotypes 19A and 6C in healthy children, similarly as in invasive pneumococcal disease. This resulted in a re-introduction of the 13-valent conjugate vaccine during the summer of 2019. [ABSTRACT FROM AUTHOR]

Objective. This study is aimed at investigating the pattern of change occurring in respiratory pathogens before and after the outbreak of COVID-19, a type of viral pneumonia for which a pandemic was declared (March 2020). The results were analyzed by gender and age to identify the association between personal hygiene and prevention of infection by respiratory pathogens. Methods. A retrospective analysis was performed on 39,814 sputum, bronchial aspirate, and transtracheal aspirate samples obtained from 15,398 patients visiting a university hospital, located in Chungcheongnam-do, South Korea, between January 2018 and December 2021. From 4,454 patients whose samples were culture positive for bacteria, 6,389 strains were isolated and further cultured. Results. The mean age of the outpatients with respiratory pathogens was 66.2 years, and the comparison of the culture test results by gender showed that 64.9% (2,892/4,454) were male and 35.1% (1,562/4,454) were female. Compared to the pre-COVID-19 pandemic period, the number of outpatients with a request for respiratory microbial cultures after the onset of the pandemic was reduced by 20.7% and the number of outpatients with a positive culture result was reduced by 23.0%. The number of respiratory samples received was reduced by 6.7% after the pandemic, while the sample positive rate was reduced by 18.3%. Among the isolated microbial strains, there was a significant decrease of 43.1% for the Acinetobacter baumannii complex, 60.5% for Streptococcus pneumoniae, 67.2% for Haemophilus influenzae, and 78.1% for Moraxella catarrhalis when compared with pre-COVID-19 levels. The distribution of respiratory microbial strains by age group showed that the highest percentage of isolated strains was in patients in their 70s. Conclusions. The improvements in personal hygiene due to the COVID-19 pandemic exerted a substantial influence on the pattern of change in other common respiratory microorganisms, which highlights the importance of personal hygiene management in the prevention of respiratory infections. [ABSTRACT FROM AUTHOR]

Background and Aim: Acinetobacter baumannii is considered to be a re-emerging causative agent of nosocomial infections. There is a significant relation between pathogenicity of this bacterium and the numerous virulence factors. The purpose of this study was to investigate nine virulence factor genes in A. baumannii isolates derived from hospitalized patients. Materials and Methods: A total of 50 A. baumannii isolates were recovered from patients with pneumonia in Imam Khomeini Hospital, Tehran, Iran. Following biochemical and microbiological identification of the bacteria, Multiplex PCR was performed for basD, plD, csuA genes, surA, pbpG, bfmR genes, and bap, ompA genes using specific sets of primers which were specifically designed for this study. The espA was identified separately by a Uniplex PCR assay. All amplified DNA fragments were sequenced for the products’ confirmation. Results: Among the 50 clinical isolates of A. baumannii studied, bfmR and pbpG genes were reported in all samples (100%), bap, plD, surA, and csuA genes were collected from 49 samples (98%), 48 (96%) of these isolates had ompA and basD genes, and espA gene was observed in only five isolates (10%). Conclusion: According to this study results, virulence factors genes in clinical A. baumannii have a prevalence rate more than 90%. Additionally, the high incidence rate of those genes related to biofilm formation indicates that most clinical strains have the ability to form biofilm structures. [ABSTRACT FROM AUTHOR]

Background We explored the nasal microbiota in Indigenous Australian children in relation to ear and nasal health. Methods In total, 103 Indigenous Australian children aged 2–7 years (mean 4.7 years) were recruited from 2 Queensland communities. Children's ears, nose, and throats were examined and upper respiratory tract (URT) swabs collected. Clinical histories were obtained from parents/medical records. URT microbiota were characterized using culturomics with Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) identification. Real-time PCR was used to quantify otopathogen (Haemophilus influenzae , Streptococcus pneumoniae , and Moraxella catarrhalis) loads and detect respiratory viruses. Data were analyzed using beta diversity measures, regression modeling, and a correlation network analysis. Results Children with historical/current otitis media (OM) or URT infection (URTI) had higher nasal otopathogen detection and loads and rhinovirus detection compared with healthy children (all P <.04). Children with purulent rhinorrhea had higher nasal otopathogen detection and loads and rhinovirus detection (P <.04) compared with healthy children. High otopathogen loads were correlated in children with historical/current OM or URTI, whereas Corynebacterium pseudodiphtheriticum and Dolosigranulum pigrum were correlated in healthy children. Conclusions Corynebacterium pseudodiphtheriticum and D. pigrum are associated with URT and ear health. The importance of the main otopathogens in URT disease/OM was confirmed, and their role relates to co-colonization and high otopathogens loads. [ABSTRACT FROM AUTHOR]

Moraxella lacunata, a low-virulence Gram-negative coccobacillus, is classically associated with conjunctivitis and upper respiratory tract infections; systemic infections such as sepsis have rarely been reported, especially in children. We describe a 28-month-old girl with atypical hemolytic uremic syndrome and stage II chronic kidney disease on long-term eculizumab therapy who presented with systemic inflammatory response syndrome and was found to have Moraxella lacunata bloodstream infection. Eculizumab, a humanized monoclonal anti-C5 antibody, has been associated with susceptibility to infections with encapsulated bacteria, especially Neisseria meningitidis. This is the first report of an invasive bacterial infection with Moraxella lacunata in a pediatric eculizumab recipient. [ABSTRACT FROM AUTHOR]

Objective: Silver has become a global treatment option with the US Food and Drug Administration providing marketing clearance for many silver-impregnated wound dressings and topical agents. However, the increased use of silver-based products across medical disciplines has raised questions concerning the development of acute silver resistance. In this study, the efficacy of previously identified silver-resistant clinical bacteria (Klebsiella pneumoniae and Enterobacter cloacae) against a variety of commercially available silver-based wound dressings was further investigated. Method: To further explore the clinical significance of these isolates, multiple time-course and repeat-challenge assays were conducted with nine dressings using a panel of silver-resistant and silversensitive microorganisms. Silver-impregnated dressings were ranked by silver species, quantity of silver and overall efficacy. Results: Both silver-resistant strains were largely unaffected and exhibited phenotypic resistance even when exposed to the high silver concentrations found in commercially available wound dressings. In stark contrast, the majority of the dressings were able to maintain a high degree of efficacy over the course of 72 hours and during repeated bacterial challenges against silver-sensitive microorganisms. Conclusion: Our findings provide additional evidence that clinically significant silver-resistance has emerged in the clinical setting. Such resistant microbes are capable of sustained silver resistance against a wide variety of silver adjuvants. These findings suggest that the further development and dissemination of these resistance mechanisms could significantly impact current practices in wound healing. Declaration of interest: The authors have no conflicts of interest to declare. [ABSTRACT FROM AUTHOR]

The present study included 250 clinical samples during the period between December 2018 -- April 2019 on 250 patients with ophthalmological infections of both sexes & different ages (3 days -75 years old), attend to ophthalmological clinic in hospital Ibn-AL-Hythem for eyes infection in Baghdad. The ophthalmological infections classified into 3 types according to the anatomical site of involvement. The first group was conjunctivitis (200) case, the 2nd was Blepharitis (35) case & the 3rd was Keratitis (15) cases. Isolation of the causative micro-organisms for the previous infections, culture & sensitivity test to different antimicrobial agents were done. The results showed that 200 (229.4)% are you giren significant growth of bacteria while 50 (69.07%) were no growth for bacteria. Include Staphylococcus aureus (77.6%), Staphylococcus epidermidis (13.6%), Streptococcus pneumonia (6.4%) & Streptococcus pyogenes (2.1%), while G-ve isolates 61 (30.5%) include (7) species of bacteria; Haemophilus influenza (81.9%), Klebsiella pneumonia (6.5%), Proteus spp & Pseudomonas aeruginosa, the Same (3.2%) for each & finally Neisseria gonorrhoeae, Moraxella spp, Acinetobacter were the least (1.6%) for each. Antimicrobial (12 agents) susceptibility of the bacterial isolates revealed marked resistant of these isolates for most antimicrobial agents e.g. Penicillin (87.8%), amoxicillin/clavulanicacid (84.4%), cephalexien (83.9%), erythromycin (83.4%), ampicillin (71.3%) while the least resistant (8.2%) reported for ciprofloxacin. [ABSTRACT FROM AUTHOR]

Background: Chronic cough is a common symptom in children and protracted bacterial bronchitis (PBB) is one of the causes of chronic cough. However, the understanding of this disease remains limited. The present study aims to update PBB in children. Methods: The clinical data of children with PBB from 2014 to 2018 were retrospectively analyzed, and PBB clinical features of published studies were summarized. Electronic databases were searched in May 2019. Clinical studies were included in the present study. Reviews were undertaken in duplicate. Results: Totally 712 cases were analyzed in this study, including 52 cases in our center and 660 cases from 14 studies. In the 52 cases, 88.5% of patients with PBB were less than 6 years old and all of them complained of wet cough. Three cases were confirmed with laryngomalacia, and microbiologically-based-PBB were identified in 13 cases (9 Streptococcus pneumonia, 3 Staphylococcus aureus, and 1 Pseudomonas aeruginosa). Twenty cases were completely remitted after treatment. In the 14 studies, the patients with PBB were typically younger than 3 years old, accompanying wheezing and airway malacia. Co-infection was common in most western cases, Streptococcus pneumonia, Haemophilus influenza and Moraxella catarrhalis were the top three pathogens. Symptoms were improved in most patients, whereas some cases with comorbidities required prolonged antibiotics treatment. Conclusions: PBB is common in male infants with chronic wet cough and accompanied by wheezing and airway deformities. Most cases are clinically diagnosed PBB in China and microbiologically-based-PBB is common in western countries. Co-infection could be found, Streptococcus pneumoniae and Haemophilus influenza were the most frequent etiology in China and western countries, respectively. Patients with comorbidities may need extended antibiotics treatment for more than 2 weeks. [ABSTRACT FROM AUTHOR]

Asthma is a chronic airway inflammatory disease that can lead to several complications caused by bacterial infections. However, recurrent attacks of the disease require long-term use of antibiotics, resulting in lung dysbiosis and poor outcomes. Daqing Formula (DQF) is a well-known herbal medicine in Pharmacopoeia of China , which is widely used for various stimuli-induced lower respiratory diseases, including asthma, bronchitis, and pneumonia. Thus, it has been demonstrated to be a plant-derived broad-spectrum antibiotic for treating and preventing various acute and chronic respiratory diseases. This study evaluated the efficacy and possible mechanism of DQF on allergic asthma and airway dysbiosis. The mice were co-challenged with ovalbumin and ampicillin to induce allergic asthma combined with airway dysbacteriosis. The populations of lung microbiota were detected by using 16s DNA sequencing. The levels of asthmatic markers in BALF were detected by ELISA. The levels of Th1/Th2 cytokines in splenic CD4+ cells of mice were analyzed by flow cytometry. The expressions of the GSK-3β signaling pathway in the lung tissues of asthmatic mice and eosinophils were detected by western blotting assay. The inhibition of DQF on the production of pro-inflammatory cytokines in eosinophils of asthmatic mice. The results showed that treatment with DQF at 200–800 mg/kg doses significantly reduced the frequency of nasal rubbing and lung inflammation as well as the number of total cells, eosinophils, and macrophages in bronchoalveolar lavage fluid. It decreased the relative abundances of Streptococcus, Cuoriavidus, and Moraxella, increased Akkermansia and Prevotella_6 in lung tissues of asthmatic mice, and inhibited the growth of Staphylococcus aureus , Klebsiella pneumoniae , Streptococcus pneumoniae and their resistant strains in vitro. Furthermore, DQF reduced the levels of eotaxin, TSLP, IL-4, IL-5, IL-25, and IL-33, but enhanced IFN-γ and IL-12 in BALF. It elevated the population of Th1 cells, inhibited eosinophil activation, and downregulated the expressions of p-GSK-3β, p-p65, nuclear β-catenin, and p-STAT3 in the lung tissues of asthmatic mice. The results revealed that DQF reduced airway inflammation, ameliorated lung dysbiosis, shifted the Th1/Th2 balance, and inhibited eosinophil activation in asthmatic mice, indicating its potential for severe asthma treatment. [Display omitted] • The abuse of antibiotics promoted the development of asthma. • DQF reduced airway inflammation induced by OVA and ampicillin in mice. • DQF ameliorated lung dysbiosis and inhibited the growth of drug-resistant bacteria. • DQF inhibited eosinophil activation via inhibiting GSK-3β-mediated pathways. • DQF prevented antibiotic abuse-induced severe asthma. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to evaluate the antibacterial efficacy of Nigella sativa (NS) seed oil against the most frequently isolated infectious bacteria of the middle and external ear Materials and Methods: The in vitro antibacterial activity of NS oil was evaluated against 34 clinical isolates of Streptococcus pneumoniae, 32 clinical isolates of Moraxella catarrhalis, 32 clinical isolates of Haemophilus influenzae, and 32 clinical isolates of Pseudomonas aeruginosa. Staphylococcus aureus, Escherichia coli, and P aeruginosa were also evaluated for their sensitivity to the NS oil. The minimum inhibitory concentration (MIC) of the NS oil was determined via a broth dilution technique. Serial solutions were prepared in a Mueller Hinton-F broth to achieve an ultimate concentration of NS oil within the microplate wells ranging from 256 ^g/mL to 0.25 ^g/mL. The growth control wells and medium were used for each bacterial strain, and the microplates were incubated at 35°C for 24 h. Those wells having no visible growth and the lowest concentration of NS oil were accepted as showing the MIC. Results: In this study a comparison was made between NS oil and the various antibiotics known to be effective against the bacterial strains mentioned above. The NS was shown to have bactericidal activity against H. influenzae, M. catarrhalis, and S. pneumoniae. However, the NS was not found to be effective against P aeruginosa at any concentration. Conclusion: The results of this laboratory-based study support the use of NS oil as an alternative treatment for ear infections. However it is necessary to conduct clinical studies to evaluate the antibacterial efficacy of NS oil on patients with ear infections. [ABSTRACT FROM AUTHOR]

Background: This document provides evidence-based clinical practice guidelines on the management of adult patients with community-acquired pneumonia.Methods: A multidisciplinary panel conducted pragmatic systematic reviews of the relevant research and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations.Results: The panel addressed 16 specific areas for recommendations spanning questions of diagnostic testing, determination of site of care, selection of initial empiric antibiotic therapy, and subsequent management decisions. Although some recommendations remain unchanged from the 2007 guideline, the availability of results from new therapeutic trials and epidemiological investigations led to revised recommendations for empiric treatment strategies and additional management decisions.Conclusions: The panel formulated and provided the rationale for recommendations on selected diagnostic and treatment strategies for adult patients with community-acquired pneumonia. [ABSTRACT FROM AUTHOR]

Abstract In this study, the physicochemical properties and bacterial community of hongeo (fermented skate) were investigated during fermentation at 10 °C. A continuous increase in pH, contents of ammonia nitrogen, amino nitrogen, free fatty acid, and released and expressible water, and total bacterial count was noticed during fermentation. Furthermore, the decrease in lightness (L∗) and increase in yellowness (b∗) were most likely caused by the Maillard reaction, as well as by lipid oxidation during fermentation, as evidenced by the increase in thiobarbituric acid reactive substances (TBARS) values. The bacterial community in hongeo samples at different fermentation stage was determined using 16S rRNA sequencing. Results of linear discriminate analysis effect size (LEfSe) analysis indicated that skate samples of the final fermentation stage were enriched in Pseudomonadales, Alteromonadales, and Burkholderiales , which showed a profound impact on the physicochemical properties of skate samples during fermentation. The identification of dominant communities in hongeo samples provides important information for selection of starter cultures consisting of strains that are well adapted to the particular production technology. Highlights • The physicochemical properties of fermented skate were investigated. • Bacterial community dynamics in skate during fermentation were analyzed. • Most bacteria in skate were members of the phylum Firmicutes and Proteobacteria. • Pseudomonas caeni was the most abundant species at the end of fermentation. [ABSTRACT FROM AUTHOR]

Lower respiratory tract infections (LRTIs) remain a challenge in African healthcare settings and only few data are available on their aetiology in Cameroon. The purpose of this study was to access the bacterial cause of LRTIs in patients in Cameroon by two methods. Methods. Participants with LRTIs were enrolled in the referral centre for respiratory diseases in Yaoundé city and its surroundings. To detect bacteria, specimens were tested by conventional bacterial culture and a commercial reverse-transcriptase real-time polymerase chain reaction (RT-PCR) assay. One hundred forty-one adult patients with LRTIs were enrolled in the study. Among the participants, 46.8% were positive for at least one bacterium. Streptococcus pneumoniae and Haemophilus influenzae were the most detected bacteria with 14.2% (20/141) followed by Klebsiella pneumoniae, 9.2% (13/141), Staphylococcus aureus, 7.1% (10/141), and Moraxella catarrhalis, 4.3% (6/141). Bacterial coinfection accounted for 23% (14/61) with Haemophilus influenzae being implicated in 19.7% (12/61). The diagnostic performance of RT-PCR for bacteria detection (43.3%) was significantly different from that of culture (17.7%) (p< 0.001). Only Streptococcus pneumoniae detection was associated with empyema by RT-PCR (p<0.001). These findings enhance understanding of bacterial aetiologies in order to improve respiratory infection management and treatment. It also highlights the need to implement molecular tools as part of the diagnosis of LRTIs. [ABSTRACT FROM AUTHOR]

A gram-stain-negative and strictly aerobic bacterium, designated strain HR-ET, was isolated from a water sample of the Han River in South Korea. Cells were catalase-negative and oxidase-positive motile rods with a flagellum. The strain grew at 10-37 °C and pH 7-8 and in the presence of 0-2% (w/v) NaCl. Ubiquinone-8 and summed features 3 (comprising C16:1ω7c and/or C16:1ω6c) and 8 (comprising C18:1ω7c and/or C18:1ω6c), C16:0, iso-C10:0 and C12:0 3-OH were identified as the major respiratory quinone and fatty acids (>5%), respectively. The 16S rRNA gene sequence of strain HR-ET shared the highest similarities with Perlucidibaca piscinae IMCC 1704T (98.1%), Perlucidibaca aquatica BK296T (96.8%), Paraperlucidibaca baekdonensis RL-2T (95.8%) and Paraperlucidibaca wandonensis WT-RY4T (95.7%). However, strain HR-ET formed a phylogenetic lineage distinct from members of the family Moraxellaceae, and a taxonomic analysis by RDP Naïve Bayesian rRNA Classifier classified strain HR-ET as a new genus of the family Moraxellaceae. In addition, analyses based on rpoD, secA and gyrB gene sequences also showed that strain HR-ET formed a lineage distinct from those of the genera Perlucidibaca and Paraperlucidibaca. Average nucleotide identity and in silico DNA-DNA hybridization values between strain HR-ET and the type strains of P. piscinae and P. aquatica were very low with 80.1 and 23.6% and 75.7 and 21.2%, respectively. The DNA G+C content was 67.0 mol%. Based on the phenotypic, genotypic and chemotaxonomic analyses, strain HR-ET represents a novel genus of the family Moraxellaceae, for which the name Amnimonas aquatica gen. nov., sp. nov. is proposed. The type strain of the type species is HR-ET (=KACC 19408T=JCM 32266T). [ABSTRACT FROM AUTHOR]

Healthcare associated infection (HAI) is known to increase the economic burden of patients while the medical cost due to MDRO HAI is even higher. Three hundred eighty-one multidrug resistance organisms (MDROs) healthcare associated infection (HAI) case-patients and three hundred eighty-one matched control-patients were identified between January and December in 2015. The average total hospitalization medical cost of the case group was $6127.65 and that of the control group was $2274.02. The difference between the case group and the control group was statistically significant (t = 21.07; P < 0.01). The attributable cost of MDRO HAI was $3853.63. The direct medical costs due to different MDRO infections were different. The increased medical costs of CR-AB, CR-KP, and CR-PA were significantly higher than that of MRSA, MRSE, ESBL E. coli, and ESBL Kp (P < 0. 05). Among the subitem expenses, the drug cost increased the most (the average cost was $1457.72), followed by the treatment fee and test fee; the differences were statistically significant (P < 0.01). [ABSTRACT FROM AUTHOR]

Moraxella lacunata is a rare coccobacillus associated with eye and upper respiratory tract infections. It may also have an affinity for bone and joint tissue. We report on 1 case of subacute osteomyelitis of the patella due to M. lacunata that presented as an osteolytic bone lesion in a child. [ABSTRACT FROM AUTHOR]

Background. Influenza A virus (IAV) has had the highest morbidity globally over the past decade. A growing number of studies indicate that the upper respiratory tract (URT) microbiota plays a key role for respiratory health and that a dysfunctional respiratory microbiota is associated with disease; but the impact of microbiota during influenza is understudied. Methods. We recruited 180 children, including 121 IAV patients and 59 age-matched healthy children. Nasopharyngeal (NP) and oropharyngeal (OP) swabs were collected to conduct 16S rDNA sequencing and compare microbiota structures in different individuals. Results. Both NP and OP microbiota in IAV patients differed from those in healthy individuals. The NP dominated genera in IVA patients, such as Moraxella, Staphylococcus, Corynebacterium, and Dolosigranulum, showed lower abundance than in healthy children. The Streptococcus significantly enriched in patients’ NP and Phyllobacterium could be generally detected in patients’ NP microbiota. The most abundant genera in OP microbiota showed a decline tendency in patients, including Streptococcus, Neisseria, and Haemophilus. The URT’s bacterial concurrence network changed dramatically in patients. NP and OP samples were clustered into subgroups by different dominant genera; and NP and OP microbiota provided the precise indicators to distinguish IAV patients from healthy children. Conclusion. This is the first respiratory microbiome analysis on pediatric IAV infection which reveals distinct NP and OP microbiota in influenza patients. It provides a new insight into IAV research from the microecology aspect and promotes the understanding of IAV pathogenesis. [ABSTRACT FROM AUTHOR]

Highlights • The emergence of homologous enzymes with different subcellular localizations. • Localization switch of homologous enzymes needs multiple evolutionary steps. • Localization switch requires innovations at genomic, genetic and enzymatic levels. Abstract After gene duplication, paralogous genes evolve independently, and consequently, the new proteins encoded by these duplicated genes are exposed to changes in their subcellular location. Although there are increasing evidence that phylogenetically related proteins play different functions in different subcellular compartments, the number of evolutionary steps required for the emergence of a novel protein with a novel subcellular localization remains unclear. Regarding this intriguing topic, here we examine in depth our previous reports describing both intracellular and extracellular polyhydroxybutyrate polymerases (PhaC) in the Pseudomonadales group. The recapitulation of the intracellular-to-extracellular localization switch of PhaC in these strains shows a gradual evolution from a simple cytosolic PhaC form to a complex extracellular PhaC form specifically secreted via the type 1 secretion system. This gradual evolution includes several adaptive and pre-adaptive changes at the genomic, genetic and enzymatic levels, which are intimately related to the lifestyle of organisms during the evolution of protein localization. We conclude that the protein localization switch can be an extremely complex process in nature. [ABSTRACT FROM AUTHOR]

Summary: Airborne bacteria are abundant and can vary with land use. Urban expansion is increasing rapidly at a global scale, altering natural sources of airborne bacterial biodiversity, as soils and native plants are replaced by pavement and managed yards. Urbanization homogenizes the biodiversity of larger organisms, but its effects are understudied with respect to microbes. This study uses categorical and gradient approaches to examine airborne bacterial communities in southwest Michigan (USA). Airborne communities carried a gut‐microbial signature and were equally homogenous above urban and rural sites, despite greater homogeneity of soil communities at urban sites. Ruminococcaceae were abundant, the source of which is likely wildlife. Beyond the gut‐microbial signature, there were underlying effects of land use, which were evident in the shared airborne taxa across urban and rural sites. Bacillales, Burkholderiales, Alteromonadales and Pseudomonadales were shared more across urban sites, while Xanthomonadales, which contains crop‐plant pathogens, were shared across rural agricultural sites. These results suggest that taxa which may distribute globally, coupled with localized sources, contribute to urban communities, while regional rural activities drive rural composition. We determined that soils were unlikely to contribute to broad distribution of some plant‐associated taxa, but may be a source for distribution of others. [ABSTRACT FROM AUTHOR]

Neutrophilic asthma (NA) is an important asthma inflammatory phenotype associated with disease severity, airflow limitation, and steroid resistance, and its mechanism is still uncertain. Evidences suggest a potential role for bacteria in its pathogenesis, but, so far, this remains poorly understood. We sought to investigate airway bacterial burden, community composition, and inflammatory response in NA. Fifty-four stable asthmatics without infection were enrolled and separated into either NA group (n = 20) or non-NA group (n = 34). Subject demographics, Asthma Control Test (ACT) scores, medications, and pulmonary functions were documented. Sputum cytology, airway bacterial burden, microbial community composition, and inflammatory cytokines were assessed. The total airway bacterial burden was significantly increased in subjects with NA versus non-NA and was positively correlated with the sputum neutrophil percentage. Airway neutrophilia was associated with less airway bacterial community richness and diversity, along with a distinct community composition. In patients with NA, bacteria in phylum Proteobacteria, especially Haemophilus spp. and Moraxella spp., showed significant increases in both actual loads and relative abundances, while bacteria in phyla Firmicutes, Actinobacteria, and Saccharibacteria showed decreased relative abundances compared with non-NA. Patients with NA demonstrated higher levels of interleukin-1β (IL-1β), IL-6, IL-8, IL-12, IL-17A, and tumor necrosis factor-α (TNF-α) in sputum samples compared with non-NA. Increased bacterial burden and distinct microbiota composition were the key characters of neutrophilic phenotype in asthma, accompanied by excessive airway inflammation. Understanding the relationship between airway microbiota and neutrophilic inflammation may help in treatment and management of asthma, such as targeting airway microbiota. [ABSTRACT FROM AUTHOR]

Plant growth promoting rhizobacteria (PGPR) belonging to the group “fluorescent pseudomonads” play very important role in sustainable agriculture. They are well known to assist plants’ health by diverse mechanisms. Potential of fluorescent pseudomonads to protect plants from a range of phytopathogens is of prime importance and gained momentum in agri-biotechnology. At global level commercialization of fluorescent pseudomonads in the form of bioinoculants for the management of several plant diseases is now considered to be very effective. Fluorescent pseudomonads are being used as effective biocontrol agents (BCA) against an array of phytopathogens. They have great potential as BCA because of the ability to produce a variety of secondary metabolites. Therefore, the objective of this review is to describe and assess the roles of secondary metabolites produced by fluorescent pseudomonads in controlling the phytopathogens and enhancing the plant health. Prominent secondary metabolites involved in biocontrol by fluorescent pseudomonads include phenazines (PHZ), 2, 4-diacetylphloroglucinol (DAPG), pyoluteorin (PLT), pyrrolnitrin (PRN), cyclic lipopeptides (CLPs) and volatile organic compounds (VOCs) such as hydrogen cyanide (HCN). These metabolites are known for antifungal, antibacterial, antiviral, antitumor and anti-nematicidal properties. Better contemporary techniques for extraction, purification and characterization may unveil the mechanisms of action of these metabolites and enable to utilize them in future bioformulations so as to replace harmful synthetic chemicals (in agriculture). [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa exhibits flagellum-mediated swimming in liquid and swarming on hydrated surfaces under diverse nutrient conditions. Prior studies have implicated a phosphodiesterase, DipA, in regulating these flagellummediated motilities, but collectively, the necessity for DipA was unclear. In this study, we find that the medium composition conditionally constrains the influence of DipA on flagellar motility. We show that DipA exhibits more influence on minimal medium supplemented with glutamate or glucose, where flagellar motility was negated for the dipA mutant. Conversely, a dipA-deficient mutant exhibits flagellar motility when growing with LB Lennox broth and minimal medium supplemented with Casamino Acids. Swarming under these rich medium conditions occurs under elevated levels of c-di-GMP. We also demonstrate that the influence of DipA upon swimming often differs from that upon swarming, and we conclude that a direct comparison of the motility phenotypes is generally valid only when characterizing motility assay results from the same medium composition. Our results are consistent with the explanation that DipA is one of several phosphodiesterases responding to the nutrient environment sensed by P. aeruginosa. On minimal medium with glutamate or glucose, DipA is dominant; however, on rich medium, the necessity of DipA is fully negated. IMPORTANCE Motile and ubiquitous bacteria such as Pseudomonas aeruginosa can quickly colonize surfaces and form biofilms in numerous environments such as water distribution systems, soil, and the human lung. To effectively disrupt bacterial colonization, it is imperative to understand how bacteria regulate motility in these different growth environments. Here, we show that the phosphodiesterase DipA is not required for flagellar motility under all nutrient conditions. Thus, the maintenance of intracellular c-di-GMP levels to promote flagellar motility or biofilm development must be conditionally regulated by differing phosphodiesterases in variation with select nutrient cues. [ABSTRACT FROM AUTHOR]

This cross-sectional study assessed the prevalence of bacteria isolated from Spanish children with suspected chronic lower respiratory tract infection (LRTI) for whom bronchoalveolar lavage (BAL) was indicated. BAL fluid (BALF) was collected from 191 children (aged ≥ 6 months to < 6 years, with persistent or recurrent respiratory symptoms, non-responders to usual treatment) and cultured. Nasopharyngeal swabs (NPSs) were also obtained and cultured to assess concordance of BALF and NPS findings in the same patient. Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis were identified from BALF with a bacterial load indicative of infection (> 104 colony-forming units/mL) in 10.5, 8.9, and 6.3% of children, respectively. Clinical characteristics were similar among participants, regardless of positivity status for any of the bacteria. Approximately 26% of pneumococcal isolates were PCV13 serotypes, and 96% of H. influenzae isolates were non-typeable (NTHi). Concordance between BALF and NPS isolates was 51.0% for S. pneumoniae, 52.1% for H. influenzae, and 22.0% for M. catarrhalis.Conclusion: S. pneumoniae, NTHi, and M. catarrhalis were the main bacteria detected in BALF and NPS. Children with suspected chronic LRTI may benefit from a vaccine protecting against NTHi. What is Known: • Chronic lower respiratory tract infection (LRTI) in children can cause high morbidity and is a major use of healthcare resources worldwide. Despite this, their etiology or potential preventive measures are poorly assessed. • Bronchoalveolar lavage can be used to determine bacterial etiology of chronic LRTI. What is New: • We used conventional and molecular techniques to show that Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis were present in the LRT of Spanish children with suspected chronic LRTI • Concordance between isolates from bronchoalveolar lavage fluid and nasopharyngeal swabs was low, suggesting that samples from the upper respiratory tract could not reliably predict the bacterial etiology of suspected chronic LRTI. [ABSTRACT FROM AUTHOR]

Bovine milk contains a complex microbial community that affects the quality and safety of the product. Detailed knowledge of this microbiota is, therefore, of importance for the dairy industry. In this study, the bacterial composition of consumption milk was assessed during different stages in the production line and throughout the storage in cartons by using culturing techniques and 16S rRNA marker gene sequencing. Monthly samples from two dairies were analyzed to capture the seasonal variations in the milk microbiota. Although there was a core microbiota present in milk samples from both dairies, the composition of the bacterial communities were significantly influenced by sampling month, processing stage and storage temperature. Overall, a higher abundance of operational taxonomic units (OTUs) within the order Bacillales was detected in samples of raw and pasteurized milk from the spring and summer months, while Pseudomonadales and Lactobacillales OTUs were predominant in the winter months. OTUs belonging to the order Lactobacillales, Pseudomonadales, Clostridiales and Bacillales were significantly more abundant in milk samples taken immediately after pasteurization compared to raw milk samples. During storage of milk in cartons at 4 °C, the bacterial composition remained stable throughout the product shelf life, while storage at 8 °C significantly increased the abundance of OTUs belonging to the genus Bacillus and the plate count levels of presumptive Bacillus cereus . The knowledge obtained in this work will be useful to the dairy industry during their quality assurance work and risk assessment practices. [ABSTRACT FROM AUTHOR]

Culturomics is a new postgenomics field that explores the microbial diversity of the human gut coupled with taxono-genomic strategy. Culturomics, and the microbiome science more generally, are anticipated to transform global health diagnostics and inform the ways in which gut microbial diversity contributes to human health and disease, and by extension, to personalized medicine. Using culturomics, we report in this study the description of strain CB1T ( = CSUR P1334 = DSM 29075), a new species isolated from a stool specimen from a 37-year-old Brazilian woman. This description includes phenotypic characteristics and complete genome sequence and annotation. Strain CB1T is a gram-negative aerobic and motile bacillus, exhibits neither catalase nor oxidase activities, and presents a 98.3% 16S rRNA sequence similarity with Pseudomonas putida. The 4,723,534 bp long genome contains 4239 protein-coding genes and 74 RNA genes, including 15 rRNA genes (5 16S rRNA, 4 23S rRNA, and 6 5S rRNA) and 59 tRNA genes. Strain CB1T was named Pseudomonas massiliensis sp. nov. and classified into the family Pseudomonadaceae. This study demonstrates the usefulness of microbial culturomics in exploration of human microbiota in diverse geographies and offers new promise for incorporating new omics technologies for innovation in diagnostic medicine and global health. [ABSTRACT FROM AUTHOR]

Background and Aim Decompensated cirrhosis is characterized by disturbed hemodynamics, immune dysfunction, and high risk of infections. Translocation of viable bacteria and bacterial products from the gut to the blood is considered a key driver in this process. Intestinal decontamination with rifaximin may reduce bacterial translocation (BT) and decrease inflammation. A randomized, placebo-controlled trial investigated the effects of rifaximin on inflammation and BT in decompensated cirrhosis. Methods Fifty-four out-patients with cirrhosis and ascites were randomized, mean age 56 years (± 8.4), and model for end-stage liver disease score 12 (± 3.9). Patients received rifaximin 550-mg BD ( n = 36) or placebo BD ( n = 18). Blood and fecal ( n = 15) sampling were conducted at baseline and after 4 weeks. Bacterial DNA in blood was determined by real-time qPCR 16S rRNA gene quantification. Bacterial composition in feces was analyzed by 16S rRNA gene sequencing. Results Circulating markers of inflammation, including tumor necrosis factor alpha, interleukins 6, 10, and 18, stromal cell-derived factor 1-α, transforming growth factor β-1, and high sensitivity C-reactive protein, were unaltered by rifaximin treatment. Rifaximin altered abundance of bacterial taxa in blood marginally, only a decrease in Pseudomonadales was observed. In feces, rifaximin decreased bacterial richness, but effect on particular species was not observed. Subgroup analyses on patients with severely disturbed hemodynamics ( n = 34) or activated lipopolysaccharide binding protein ( n = 37) revealed no effect of rifaximin. Conclusion Four weeks of treatment with rifaximin had no impact on the inflammatory state and only minor effects on BT and intestinal bacterial composition in stable, decompensated cirrhosis (NCT01769040). [ABSTRACT FROM AUTHOR]

Intravenous (IV) minocycline (Minocin) is approved in the USA for use in patients with infections due to susceptible strains of many bacteria (e.g. Gram-positive and Gram-negative pathogens, including infections due to Acinetobacter spp.). Minocycline shows antibacterial activity against A. baumannii clinical isolates worldwide, and exhibits synergistic bactericidal activity against multidrug-resistant (MDR) and extensively drug-resistant (XDR) A. baumannii isolates when combined with other antibacterial agents. In retrospective studies, IV minocycline provided high rates of clinical success or improvement, and was generally well tolerated among patients with MDR or carbapenem-resistant A. baumannii infections. [ABSTRACT FROM AUTHOR]

Microbial denitrification in agriculture makes a considerable contribution to terrestrial nitrous oxide (N 2 O) emissions, and the prevailing view is that this mainly occurs in soil. Here, we show the root N 2 O emission capacity of wheat grown under three long-term (32-year) fertilization regimes, and compare root-, rhizosphere- and soil-inhabiting denitrifying microbial communities. The N 2 O/(N 2 O + N 2 ) product ratio of denitrification in the root was 0.5–9.2-fold higher than that in surrounding soil under fertilized conditions, especially manure application. Root N 2 O/(N 2 O + N 2 ) ratio was closely related to the proportion of two nitrite-reductase genes ( nirK / nirS ), with higher N 2 O emission associated with increased nirS abundance. Rhodobacterales and Pseudomonadales dominated the root-associated nirS community. In contrast, soils showed a higher proportion of unclassified denitrifiers. Our results demonstrate the potential of wheat to emit N 2 O from the roots that harbour low-complexity denitrifying communities distinct from those occurred in soils. [ABSTRACT FROM AUTHOR]

Citrus canker, caused by bacteria Xanthomonas citri subsp. citri , can affect all economically important varieties of citrus. Studying Xanthomonas genes related to the invasive capacity may improve the knowledge on how this works and ultimately use the information to avoid the disease. Some annotated genes from Xanthomonas citri subsp. citri published genome are addressed to an interesting class of genes named “pathogenicity, virulence and adaptation”. One of them is xanA , which encodes a predicted phosphoglucomutase. Phosphoglucomutases are ubiquitous enzymes among the living kingdoms that play roles in carbohydrate metabolism, catalyzing the reversible conversion of 1- to 6-phosphoglucose. In Xanthomonas , phosphoglucomutase activity is required to synthesize precursors of the pathogenesis-related polysaccharide xanthan. In this work, a characterization of this gene product is presented by structural and functional studies. Molecular cloning was used for heterologous expression and deletion of xanA . A Michaelis-Menten kinetics model was obtained using the recombinant protein. The protein structure was also determined by X-ray diffraction on the recombinant enzyme substrate-free, bound to glucose-1,6-biphosphate and to glucose-1-phosphate. Deletion of xanA was done with a suicide plasmid construct and the obtained mutant was tested for pathogenic capacity. This study is the first describing the properties of the Xanthomonas citri subsp. citri phosphoglucomutase. [ABSTRACT FROM AUTHOR]

Background: The emergence of Moraxella catarrhalis as a nosocomial pathogen in the last decade with increasing prevalence of antibiotic resistant strains has gained interest. In immunocompromised hosts, the bacterium can cause a variety of severe infections, including pneumonia, endocarditis, septicemia and meningitis. Aim: The purpose of our current study was to evaluate the prevalence and resistance pattern of M. catarrhalis causing RTI among cancer patients. Methods: Patients suspected to be suffering from respiratory tract infection (RTI) were taken up for the study. All specimens were cultured. Identification was done by standard microbiological methods. Certain criteria were considered for determining the pathogenic significance of Moraxella catarrhalis. Result: Out of the total 355 respiratory samples received, 100 (28.1%) respiratory samples showed meaningful growths. The rest of 255 (71.8%) of the respiratory samples produced no significant respiratory bacterial pathogen or no growth. Out of the 100 meaningful samples 124 respiratory pathogens were isolated. Among 124 isolates 19 (15.3%) were Moraxella catarrhalis. Other bacterial isolates were as follows: Pseudomonas aeruginosa 17 (13.7%), Klebsiella pneumoniae 17 (13.7%), Escherichia coli 14 (11.2%), Acinetobacter baumanii 10 (8.0%), Streptococcus spp 10 (8.0%), Staphylococcus spp 9 (7.2%), Candida albicans 8 (6.4%), Staphylococcus aureus 7 (5.6%) and others 13 (10.4%). The finding shows M. catarrhalis as one of the predominant bacterial pathogen causing respiratory tract infection in cancer patients. The susceptibility pattern of M. catarrhalis showed that all the isolates were more susceptible to Amoxycillin-clavulanic acid (57.8%), followed by Chloramphenicol (50.1%). Patients (47.3%) with lung carcinoma were found to be more prone to get infection by M. catarrhalis. Conclusion: Keeping in mind the increasing prevalence of patients being infected with M. catarrhalis in our region, a larger scale research should be conducted to evaluate resistance pattern of M. catarrhalis. Continued surveillance of antimicrobial susceptibility pattern and application of control measures against further transmission are required to decrease the emergence of the resistant strains. [ABSTRACT FROM AUTHOR]

To better characterize the bacterial community members capable of biosurfactant production on leaves, we distinguished culturable biosurfactant-producing bacteria from nonproducers and used community sequencing to compare the composition of these distinct cultured populations with that from DNA directly recovered from leaves. Communities on spinach, romaine, and head lettuce leaves were compared with communities from adjacent samples of soil and irrigation source water. Soil communities were poorly described by culturing, with recovery of cultured representatives from only 21% of the prevalent operational taxonomic units (OTUs) (>0.2% reads) identified. The dominant biosurfactant producers cultured from soil included bacilli and pseudomonads. In contrast, the cultured communities from leaves are highly representative of the culture-independent communities, with over 85% of the prevalent OTUs recovered. The dominant taxa of surfactant producers from leaves were pseudomonads as well as members of the infrequently studied genus Chryseobacterium. The proportions of bacteria cultured from head lettuce and romaine leaves that produce biosurfactants were directly correlated with the culture-independent proportion of pseudomonads in a given sample, whereas spinach harbored a wider diversity of biosurfactant producers. A subset of the culturable bacteria in irrigation water also became enriched on romaine leaves that were irrigated overhead. Although our study was designed to identify surfactant producers on plants, we also provide evidence that most bacteria in some habitats, such as agronomic plant surfaces, are culturable, and these communities can be readily investigated and described by more classical culturing methods. [ABSTRACT FROM AUTHOR]

Background: Moraxella catarrhalis is an established pathogen that is causing substantial infections to both children and adults. However, so far there is no effective vaccine to halt the spread of these infections.Methods: Immunoinformatics tools were used to predict M. catarrhalis epitopes that could offer immunoprotection among major proportions of human populations worldwide. Mice were immunized with the best 3 peptides and then challenged with M. catarrhalis in the pulmonary clearance model. Finally, antibodies against these epitopes were detected in humans.Results: Immunoinformatics analyses identified 44 epitopes that are predicted to be good major histocompatibility complex class II binders and at the same time show high population coverage worldwide. After intraperitoneal immunization of mice with the best 3 peptides, peptide A, derived from lactoferrin-binding protein A, showed superior activity in immunogenicity and in clearing M. catarrhalis from mouse lungs. Higher clearance was obtained by combining intraperitoneal and intranasal immunization. In the serum samples from children with otitis media infected with M. catarrhalis, antibody levels against peptide A were significantly lower than in samples from children without otitis media.Conclusions: Peptide A is the first promising peptide-based vaccine against M. catarrhalis Immunoinformatics predicts that it should have a global protection around the world. [ABSTRACT FROM AUTHOR]

Pseudomonads and lactic acid bacteria ( LAB) are the most relevant organisms for assessing the effect of specific chilling time-temperature scenarios on the growth of spoilage bacteria under aerobic and anaerobic (vacuum packs) conditions, respectively. Pseudomonad growth was modelled on beef, pork and lamb carcasses, chilled to specific target surface temperatures and compared with the growth that would be achieved if the carcasses were chilled to a core temperature of 7°C (Regulation ( EC) No 853/2004). Pseudomonad growth with the combination of chilling the carcass surface to a target temperature (1-10°C for beef and lamb, and 5-10°C for pork) and transportation at that temperature plus ± 1°C was also modelled for 1-48 h (assuming an initial count of 1 CFU/cm2). Finally, the growth of pseudomonads and LAB was modelled on meat intended for use in minced meat/meat preparations, stored at temperatures of 1-7°C (inclusive) for 1-12 days. The effect of storage temperature and initial count on the time to reach 107 CFU/cm2 was also investigated. The outputs suggest that chilling bovine or ovine carcasses to between 4 and 10°C surface temperature, inclusive, results in similar or lower predicted pseudomonad growth as compared to chilling to a core temperature of 7°C. The results for porcine carcasses depended on the target surface temperature and chilling curve applied. It was also predicted that pseudomonads and LAB grow steadily on meat stored at 1-7°C and LAB counts exceeded 107 CFU/cm2 when stored for 11 days at 7°C. It was concluded that the time-temperature chilling profiles that may be used to obtain similar or less growth to that obtained when chilling to a core temperature of 7°C is dependent on the initial contamination level. [ABSTRACT FROM AUTHOR]

Rationale: Cystic fibrosis (CF) is characterized by early structural lung disease caused by pulmonary infections. The nasopharynx of infants is a major ecological reservoir of potential respiratory pathogens.Objectives: To investigate the development of nasopharyngeal microbiota profiles in infants with CF compared with those of healthy control subjects during the first 6 months of life.Methods: We conducted a prospective cohort study, from the time of diagnosis onward, in which we collected questionnaires and 324 nasopharynx samples from 20 infants with CF and 45 age-matched healthy control subjects. Microbiota profiles were characterized by 16S ribosomal RNA-based sequencing.Measurements and Main Results: We observed significant differences in microbial community composition (P < 0.0002 by permutational multivariate analysis of variance) and development between groups. In infants with CF, early Staphylococcus aureus and, to a lesser extent, Corynebacterium spp. and Moraxella spp. dominance were followed by a switch to Streptococcus mitis predominance after 3 months of age. In control subjects, Moraxella spp. enrichment occurred throughout the first 6 months of life. In a multivariate analysis, S. aureus, S. mitis, Corynebacterium accolens, and bacilli were significantly more abundant in infants with CF, whereas Moraxella spp., Corynebacterium pseudodiphtericum and Corynebacterium propinquum and Haemophilus influenzae were significantly more abundant in control subjects, after correction for age, antibiotic use, and respiratory symptoms. Antibiotic use was independently associated with increased colonization of gram-negative bacteria such as Burkholderia spp. and members of the Enterobacteriaceae bacteria family and reduced colonization of potential beneficial commensals.Conclusions: From diagnosis onward, we observed distinct patterns of nasopharyngeal microbiota development in infants with CF under 6 months of age compared with control subjects and a marked effect of antibiotic therapy leading toward a gram-negative microbial composition. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a common biofilm-forming bacterial pathogen implicated in diseases of the lungs. The extracellular polymeric substances (EPS) of respiratory Pseudomonas biofilms are largely comprised of anionic molecules such as rhamnolipids and alginate that promote a mucoid phenotype. In this Letter, we examine the ability of negatively-charged fluoroquinolones to transverse the EPS and inhibit the growth of mucoid P. aeruginosa . Anionic fluoroquinolones were further compared with standard antibiotics via a novel microdiffusion assay to evaluate drug penetration through pseudomonal alginate and respiratory mucus from a patient with cystic fibrosis. [ABSTRACT FROM AUTHOR]

Background: Invasive diseases due to Moraxella catarrhalis are rare in children, even in immunocompromised hosts. Therefore, data regarding clinical characteristics and risk factors of such patients are limited. The aim of this study is to compare the clinical characteristics of patients with bacteremia due to Moraxella catarrhalis against those with bacteremia due to Streptococcus pneumoniae and Haemophilus influenzae.Methods: We performed a retrospective case-control study to compare patients younger than 18 years of age with positive blood cultures for the three pathogens between June 2008 and May 2014 at our institution. Data regarding patients' demographics and clinical course were collected from their medical records. Three group comparisons, with M. catarrhalis as reference, were made by the Fisher's exact test and Wilcoxon rank sum test for discrete and continuous variables, respectively.Results: There were eight cases of M. catarrhalis, 110 cases of S. pneumoniae (105 patients) and 22 cases of H. influenzae. The M. catarrhalis group consisted of six females (75 %) with a mean age of 16 months. The majority of patients (7/8, 88 %) had underlying diseases; however, only one was immunocompromised. Characteristically, six patients (75 %) had medical devices including trans-nasal devices (5/8, 63 %). Univariate analysis revealed that underlying conditions (P = 0.005), trans-nasal devices (P < 0.001), and lower body weight (P = 0.016) and low white blood cell count (P = 0.011) at the onset of illness were associated with the M. catarrhalis group compared to the S. pneumoniae group. Meanwhile, the higher rates of the patients with underlying conditions and trans-nasal devices were associated with the M. catarrhalis group compared to the H. influenzae group (P = 0.039, P < 0.001, respectively).Conclusions: The presence of underlying conditions, particularly in those with trans-nasal devices, were characteristic features of patients with bacteremia due to M. catarrhalis. [ABSTRACT FROM AUTHOR]