Tea consumption and risk of lower respiratory tract infections: a two-sample mendelian randomization study.

BACKGROUND: Observational studies have reported the association between tea consumption and the risk of lower respiratory tract infections (LRTIs). However, a consensus has yet to be reached, and whether the observed association is driven by confounding factors or reverse causality remains unclear. METHOD: A two-sample Mendelian randomization (MR) analysis was conducted to determine whether genetically predicted tea intake is causally associated with the risk of common LRTI subtypes. Genome-wide association study (GWAS) from UK Biobank was used to identify single-nucleotide polymorphisms (SNPs) associated with an extra cup of tea intake each day. The summary statistics for acute bronchitis, acute bronchiolitis, bronchiectasis, pneumonia, and influenza and pneumonia were derived from the FinnGen project. RESULTS: We found that genetically predicted an extra daily cup of tea intake was causally associated with the decreased risk of bronchiectasis [odds ratio (OR) = 0.61, 95% confidence interval (CI) = 0.47-0.78, P < 0.001], pneumonia (OR = 0.90, 95% CI = 0.85-0.96, P = 0.002), influenza and pneumonia (OR = 0.91, 95% CI = 0.85-0.97, P = 0.002), but not with acute bronchitis (OR = 0.91, 95% CI = 0.82-1.01, P = 0.067) and acute bronchiolitis (OR = 0.79, 95% CI = 0.60-1.05, P = 0.100). Sensitivity analyses showed that no heterogeneity and pleiotropy could bias the results. CONCLUSIONS: Our findings provided new evidence that genetically predicted an extra daily cup of tea intake may causally associated with a decreased risk of bronchiectasis, pneumonia, and influenza and pneumonia.

Host-Based Diagnostics for Acute Respiratory Infections.

PURPOSE: The inappropriate use of antimicrobials, especially in acute respiratory infections (ARIs), is largely driven by difficulty distinguishing bacterial, viral, and noninfectious etiologies of illness. A new frontier in infectious disease diagnostics looks to the host response for disease classification. This article examines how host response-based diagnostics for ARIs are being used in clinical practice, as well as new developments in the research pipeline. METHODS: A limited search was conducted of the relevant literature, with emphasis placed on literature published in the last 5 years (2014-2019). FINDINGS: Advances are being made in all areas of host response-based diagnostics for ARIs. Specifically, there has been significant progress made in single protein biomarkers, as well as in various "omics" fields (including proteomics, metabolomics, and transcriptomics) and wearable technologies. There are many potential applications of a host response-based approach; a few key examples include the ability to discriminate bacterial and viral disease, presymptomatic diagnosis of infection, and pathogen-specific host response diagnostics, including modeling disease progression. IMPLICATIONS: As biomarker measurement technologies continue to improve, host response-based diagnostics will increasingly be translated to clinically available platforms that can generate a holistic characterization of an individual's health. This knowledge, in the hands of both patient and provider, can improve care for the individual patient and help fight rising rates of antibiotic resistance.

Role of the zinc uptake ABC transporter of Moraxella catarrhalis in persistence in the respiratory tract.

Moraxella catarrhalis is a human respiratory tract pathogen that causes otitis media in children and lower respiratory tract infections in adults with chronic obstructive pulmonary disease. We have identified and characterized a zinc uptake ABC transporter that is present in all strains of M. catarrhalis tested. A mutant in which the znu gene cluster is knocked out shows markedly impaired growth compared to the wild type in medium that contains trace zinc; growth is restored to wild-type levels by supplementing medium with zinc but not with other divalent cations. Thermal-shift assays showed that the purified recombinant substrate binding protein ZnuA binds zinc but does not bind other divalent cations. Invasion assays with human respiratory epithelial cells demonstrated that the zinc ABC transporter of M. catarrhalis is critical for invasion of respiratory epithelial cells, an observation that is especially relevant because an intracellular reservoir of M. catarrhalis is present in the human respiratory tract and this reservoir is important for persistence. The znu knockout mutant showed marked impairment in its capacity to persist in the respiratory tract compared to the wild type in a mouse pulmonary clearance model. We conclude that the zinc uptake ABC transporter mediates uptake of zinc in environments with very low zinc concentrations and is critical for full virulence of M. catarrhalis in the respiratory tract in facilitating intracellular invasion of epithelial cells and persistence in the respiratory tract.

Serum levels of 25-hydroxyvitamin D and the CYP3A biomarker 4ß-hydroxycholesterol in a high-dose vitamin D supplementation study.

The primary aim was to study the relationship between individual serum levels of 25-hydroxyvitamin D and 4ß-hydroxycholesterol, which is an endogenous biomarker of the drug-metabolizing CYP3A enzymes. In addition, the relationship between this biomarker and inflammation, measured as C-reactive protein (CRP), was investigated. Serum samples were used from a recently performed clinical trial in patients with antibody deficiency or increased susceptibility to respiratory tract infections that were randomized to either placebo or high-dose (4000 IU/day) vitamin D for 12 months. One hundred sixteen patients were included in the final analyses, and serum samples collected 6 months after study start were analyzed. At this time point, 25-hydroxyvitamin D levels were found to range between 10 and 284 nM. Individual levels of 25-hydroxyvitamin D as well as CRP were compared with 4ß-hydroxycholesterol levels. In addition, all participants were genotyped for two polymorphisms (Taq1 and Foq1) in the vitamin D receptor gene. There was no significant correlation between individual serum levels of 25-hydroxyvitamin D and 4ß-hydroxycholesterol. However, a moderate, but statistically significant, negative correlation between CRP and 4ß-hydroxycholesterol levels was observed. This study in patients with highly variable serum levels of 25-hydroxyvitamin D could not reveal any relationship between vitamin D and 4ß-hydroxycholesterol, an endogenous biomarker of CYP3A activity. However, the negative correlation between CRP and 4ß-hydroxycholesterol supports earlier experimental results that inflammation may suppress hepatic CYP3A activity, a finding of potentially high clinical relevance that warrants further exploration.

Sleepiness that cannot be overcome: narcolepsy and cataplexy.

Narcolepsy-cataplexy syndrome is characterized by excessive daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations and disturbed nocturnal sleep. It is strongly associated with the genetic marker, human leucocyte antigen (HLA) DQB1*06:02. A deficit in the endogenous hypocretin/orexin system due to neuronal degeneration in the lateral hypothalamus, induced by an autoimmune-mediated process, is the primary pathophysiology associated with the human disease. The important finding of an association with hypocretin genes in animal models of narcolepsy has led to the establishment of cerebrospinal fluid hypocretin measurements as a new diagnostic test for human narcolepsy. This is a fascinating story of translation of basic science research into clinical practice in sleep medicine during the past decade. Recent advances have shed light on the associations between respiratory medicine and narcolepsy-cataplexy research. The first is that upper airway infections, including H1N1 and/or streptococcal infections, may initiate or reactivate an immune response that leads to loss of hypocretin-secreting cells and narcolepsy in genetically susceptible individuals. The second is that an increased incidence of sleep disordered breathing among narcoleptic subjects may relate to the impairment of central control of breathing, linked to hypocretin deficiency or carriage of HLADQB1*06:02, in animals and human subjects with narcolepsy, respectively, indicating neural dysfunction in an area where respiratory and sleep-wake systems are closely interrelated.

[Polarized light as an epigenetic factor in inhibition of inflammation; a genome-wide expression analysis in recurrent respiratory diseases of children]. / A polarizált fény epigenetikai tényezo a gyulladásgátlásban; teljesgenom-szintu expressziós analízis gyermekkori visszatéro légúti megbetegedésekben.

UNLABELLED: Whole-body polarized light therapy has been primarily investigated in various clinical observations and in a few in vitro model systems. AIMS: In the present study, clinical and molecular effects of whole-body polarized light treatment on children suffering from recurrent respiratory infection were studied. METHODS: Incidence and duration of respiratory symptoms as well as the length of appropriate antibiotic therapy have been measured. Simultaneously, genome-wide gene expression pattern was examined by whole genome cDNA microarray in peripheral lymphocytes of children. RESULTS: Twenty of twenty five children showed a marked clinical improvement, while in five of twenty five had poor or no changes. Gene expression pattern of the peripheral lymphocytes of the patients was compared in favorable and poor responders. Lymphocytes of the children with a documented improved clinical response to polarized light therapy showed a decrease in the expression of chemokine genes, such as CXCL1, CXCL2, IL-8 and in that of the tumor necrosis alpha (TNFα) gene. On the contrary, a rapid elevation was found in the expression of gene encoding for CYP4F2, a leukotriene-B(4)-metabolizing enzyme. In children with poor clinical response to polarized light therapy, no similar changes were detected in the gene expression pattern of the lymphocytes. CONCLUSIONS: Improved clinical symptoms and modified gene expression profile of lymphocytes reveals anti-inflammatory effect upon whole body polarized light irradiation.

Genome-wide gene expression study indicates the anti-inflammatory effect of polarized light in recurrent childhood respiratory disease.

OBJECTIVES: The clinical and molecular effects of whole-body polarized light treatment on children suffering from recurrent respiratory infection were studied. METHODS: The incidence and duration of respiratory symptoms as well as the length of appropriate antibiotic therapy were measured. Simultaneously, the genome-wide gene expression pattern was examined by whole genome cDNA microarray in peripheral lymphocytes of children. RESULTS: Twenty of 25 children showed a marked clinical improvement, while in five of 25 had poor response or no changes. The gene expression pattern of the patients' peripheral lymphocytes was compared in favorable and poor responders. The lymphocytes of the children with a documented improved clinical response to polarized light therapy showed a decrease in the expression of chemokine genes, such as CXCL1, CXCL2, CXCL3, and IL-8, and in that of the TNFα gene. On the contrary, a rapid elevation was found in the expression of the gene encoding for CYP4F2, a leukotriene B4-metabolizing enzyme. In children with poor clinical response to polarized light therapy, no similar changes were detected in the gene expression pattern of the lymphocytes. CONCLUSIONS: The improved clinical symptoms and modified gene expression profile of lymphocytes reveals an anti-inflammatory effect of whole-body polarized light irradiation.

IL-2 and IL-10 gene polymorphisms are associated with respiratory tract infection and may modulate the effect of vitamin E on lower respiratory tract infections in elderly nursing home residents.

BACKGROUND: Vitamin E supplementation may be a potential strategy to prevent respiratory tract infections (RIs) in the elderly. The efficacy of vitamin E supplementation may depend on individual factors including specific single nucleotide polymorphisms (SNPs) at immunoregulatory genes. OBJECTIVE: We examined whether the effect of vitamin E on RIs in the elderly was dependent on genetic backgrounds as indicated by SNPs at cytokine genes. DESIGN: We used data and DNA from a previous vitamin E intervention study (200 IU vitamin E or a placebo daily for 1 y) in elderly nursing home residents to examine vitamin E-gene interactions for incidence of RI. We determined the genotypes of common SNPs at IL-1beta, IL-2, IL-6, IL-10, TNF-alpha, and IFN-gamma in 500 participants. We used negative binomial regression to analyze the association between genotype and incidence of infection. RESULTS: The effect of vitamin E on lower RI depended on sex and the SNP at IL-10 -819G-->A (P = 0.03 for interaction for lower RI). Furthermore, we observed that subjects with the least prevalent genotypes at IL-2 -330A-->C (P = 0.02 for upper RI), IL-10 -819G-->A (P = 0.08 for upper RI), and IL-10 -1082C-->T (P < 0.001 for lower RI in men) had a lower incidence of RI independent of vitamin E supplementation. CONCLUSIONS: Studies that evaluate the effect of vitamin E on RIs should consider both genetic factors and sex because our results suggest that both may have a significant bearing on the efficacy of vitamin E. Furthermore, common SNPs at cytokine genes may contribute to the individual risk of RIs in the elderly. This trial was registered at clinicaltrials.gov as NCT00758914.

Antibacterial resistance among children with community-acquired respiratory tract infections (PROTEKT 1999-2000).

OBJECTIVE: To determine the susceptibility of bacterial respiratory tract pathogens, isolated from children (0-12 years) as part of the global PROTEKT surveillance study (1999-2000), to a range of antibacterials, including the ketolide telithromycin. METHODS: Minimum inhibitory concentrations of the antibacterials studied were determined at a central laboratory using the NCCLS microdilution broth method. Macrolide resistance mechanisms were detected by PCR. RESULTS: Of 779 Streptococcus pneumoniae isolates worldwide, 43% were non-susceptible to penicillin (18% intermediate; 25% resistant) and 37% were resistant to erythromycin, with considerable intercountry variation. Eighteen per cent of 653 Haemophilus influenzae and >90% of 316 Moraxella catarrhalis isolates produced beta-lactamase. Of 640 Streptococcus pyogenes isolates, 10% were resistant to erythromycin, with considerable intercountry variation. All S. pneumoniae and 99.8% of H. influenzae isolates were susceptible to telithromycin using breakpoints proposed to the NCCLS (

Evolving resistance patterns in community-acquired respiratory tract pathogens: first results from the PROTEKT global surveillance study. Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin.

In recent years, antibacterial resistance among respiratory pathogens implicated in community-acquired respiratory tract infections (RTIs) has spread worldwide at an alarming rate. Thus, there is a pressing need for new antibacterials that retain activity against resistant organisms, have a low potential to select for resistance and do not induce cross-resistance. Telithromycin is the first of a new class of antibacterials - the ketolides - that have been designed specifically to overcome resistance among respiratory tract pathogens. This paper presents the first results of the PROTEKT study (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin), a worldwide surveillance study initiated to chart the prevalence of important resistance phenotypes and genotypes and the comparative activity of telithromycin against such strains. Analysis of over 7,000 bacterial isolates by April 2001 has confirmed the notable prevalence of strains resistant to commonly prescribed RTI antibacterials for all the pathogens studied. Telithromycin demonstrates high activity against isolates of Streptococcus pneumoniae, irrespective of penicillin G, macrolide or fluoroquinolone resistance. Telithromycin is also highly active against other respiratory tract pathogens, including Streptococcus pyogenes and beta-lactamase-producing strains of Haemophilus influenzae and Moraxella catarrhalis. These data justify the assertion that telithromycin is a promising new candidate for the empirical treatment of community-acquired RTIs, particularly in the face of increasing antibacterial resistance.