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Microbiome Jul 2023Secondary bacterial infections and pneumonia are major mortality causes of respiratory viruses, and the disruption of the upper respiratory tract (URT) microbiota is a...
BACKGROUND
Secondary bacterial infections and pneumonia are major mortality causes of respiratory viruses, and the disruption of the upper respiratory tract (URT) microbiota is a crucial component of this process. However, whether this URT dysbiosis associates with the viral species (in other words, is viral type-specific) is unclear.
RESULTS
Here, we recruited 735 outpatients with upper respiratory symptoms, identified the infectious virus types in 349 participants using multiplex RT-PCR, and profiled their upper respiratory microbiome using the 16S ribosomal RNA gene and metagenomic gene sequencing. Microbial and viral data were subsequently used as inputs for multivariate analysis aimed at revealing viral type-specific disruption of the upper respiratory microbiota. We found that the oropharyngeal microbiota shaped by influenza A virus (FluA), influenza B virus (FluB), respiratory syncytial virus (RSV), and human rhinovirus (HRV) infections exhibited three distinct patterns of dysbiosis, and Veillonella was identified as a prominent biomarker for any type of respiratory viral infections. Influenza virus infections are significantly correlated with increased oropharynx microbiota diversity and enrichment of functional metabolic pathways such as L-arginine biosynthesis and tetracycline resistance gene tetW. We used the GRiD algorithm and found the predicted growth rate of common respiratory pathogens was increased upon influenza virus infection, while commensal bacteria, such as Streptococcus infantis and Streptococcus mitis, may act as a colonization resistance to the overgrowth of these pathogens.
CONCLUSIONS
We found that respiratory viral infections are linked with viral type-specific disruption of the upper respiratory microbiota, particularly, influenza infections uniquely associated with increased microbial diversity and growth rates of specific pathogens in URT. These findings are essential for clarifying the differences and dynamics of respiratory microbiota in healthy participants and acute respiratory viral infections, which contribute to elucidating the pathogenesis of viral-host-bacterial interactions to provide insights into future studies on effective prevention and treatment of respiratory tract infections. Video Abstract.
Topics: Humans; Influenza, Human; Dysbiosis; Respiratory Tract Infections; Orthomyxoviridae Infections; Oropharynx; Bacteria; Influenza A virus; Coinfection
PubMed: 37482605
DOI: 10.1186/s40168-023-01597-9 -
Emerging Microbes & Infections Dec 2023The development of novel culture-independent techniques of microbial identification has allowed a rapid progress in the knowledge of the nasopharyngeal microbiota and...
The development of novel culture-independent techniques of microbial identification has allowed a rapid progress in the knowledge of the nasopharyngeal microbiota and its role in health and disease. Thus, it has been demonstrated that the nasopharyngeal microbiota defends the host from invading pathogens that enter the body through the upper airways by participating in the modulation of innate and adaptive immune responses. The current COVID-19 pandemic has created an urgent need for fast-track research, especially to identify and characterize biomarkers to predict the disease severity and outcome. Since the nasopharyngeal microbiota diversity and composition could potentially be used as a prognosis biomarker for COVID-19 patients, which would pave the way for strategies aiming to reduce the disease severity by modifying such microbiota, dozens of research articles have already explored the possible associations between changes in the nasopharyngeal microbiota and the severity or outcome of COVID-19 patients. Unfortunately, results are controversial, as many studies with apparently similar experimental designs have reported contradictory data. Herein we put together, compare, and discuss all the relevant results on this issue reported to date. Even more interesting, we discuss in detail which are the limitations of these studies, that probably are the main sources of the high variability observed. Therefore, this work is useful not only for people interested in current knowledge about the relationship between the nasopharyngeal microbiota and COVID-19, but also for researchers who want to go further in this field while avoiding the limitations and variability of previous works.
Topics: Humans; COVID-19; Pandemics; Nasopharynx; Microbiota; Nose
PubMed: 36606725
DOI: 10.1080/22221751.2023.2165970 -
Laryngo- Rhino- Otologie Jan 2024
Topics: Humans; Trachea; Hypopharynx; Larynx
PubMed: 38181779
DOI: 10.1055/a-2169-9226 -
Anatomia, Histologia, Embryologia Sep 2023Giant anteater (Myrmecophaga tridactyla) is an endangered species that resides in much of Latin America, but it has been losing its habitat, especially in the Cerrado...
Giant anteater (Myrmecophaga tridactyla) is an endangered species that resides in much of Latin America, but it has been losing its habitat, especially in the Cerrado biome, where it constantly suffers traumas resulting from fires and roadkill. The anatomical knowledge of structures of the respiratory system is important for a better morphophysiological understanding of the species. Thus, this study aimed to perform the macroscopic and histomorphological description of the pharynx and larynx of the giant anteater. Twelve adult giant anteaters were used, three of them fixed in buffered formalin for further dissection and pharynx and larynx macroscopic analysis of structures. From the other animals, samples of the pharynx and larynx were collected and prepared for histological evaluation under optical microscope. Macroscopically, their pharynx and soft palate are extensive, and the anatomical location of these structures and the larynx differs greatly from that described in other species. The larynx, although more caudal, was similar to that of other animals. Histologically, the epithelium of these regions varied between the pseudostratified ciliated columnar and the non-keratinized stratified squamous epithelium. Laryngeal cartilages were composed of elastic (epiglotti) and hyaline cartilages (arytenoid, cricoid and thyroid cartilage), with an ossification process and glandular clusters around the hyaline cartilage. The distinct anatomical location of the pharynx and larynx of Myrmecophaga tridactyla is the main macroscopic finding of this study, besides the length of the pharynx and soft palate of these animals.
Topics: Animals; Vermilingua; Xenarthra; Pharynx; Larynx; Microscopy
PubMed: 37096428
DOI: 10.1111/ahe.12928 -
Current Opinion in Microbiology Feb 2024The respiratory tract microbiome (RTM) is a microbial ecosystem inhabiting different niches throughout the airway. A critical role for the RTM in dictating lung... (Review)
Review
The respiratory tract microbiome (RTM) is a microbial ecosystem inhabiting different niches throughout the airway. A critical role for the RTM in dictating lung infection outcomes is underlined by recent efforts to identify community members benefiting respiratory tract health. Obligate anaerobes common in the oropharynx and lung such as Prevotella and Veillonella are associated with improved pneumonia outcomes and activate several immune defense pathways in the lower airway. Colonizers of the nasal cavity, including Corynebacterium and Dolosigranulum, directly impact the growth and virulence of lung pathogens, aligning with robust clinical correlations between their upper airway abundance and reduced respiratory tract infection risk. Here, we highlight recent work identifying respiratory tract bacteria that promote airway health and resilience against disease, with a focus on lung infections and the underlying mechanisms driving RTM-protective benefits.
Topics: Humans; Lung; Oropharynx; Respiratory Tract Infections; Pneumonia, Bacterial; Microbiota
PubMed: 38277901
DOI: 10.1016/j.mib.2024.102428 -
The Journal of Craniofacial SurgeryThe study was performed to analyze the oropharynx airway and examine the influence of age and gender on the oropharynx volume configuration using cone beam computed...
OBJECTIVE
The study was performed to analyze the oropharynx airway and examine the influence of age and gender on the oropharynx volume configuration using cone beam computed tomography.
MATERIALS AND METHODS
This study examined the cone beam computed tomographic images of 51 patients 25 male and 26 females, group matched for age and gender. The oropharynx airway volume and area between the posterior nasal spine and top of the epiglottis were measured and compared.
RESULTS
The statistical measurements of 51 cone beam computed tomography images showed a nonsignificant difference found between male and female regarding the age (the mean age for female 40.15 y. and for male32.72 y). Male subjects had greater oropharynx volume, a high significant difference ( P =0.005) in oropharynx volume between the 3 age groups. A significant difference was found between the smallest age group with the larger age groups.
CONCLUSION
The study data revealed that the changes in measurements of oropharynx airway are age-dependent in addition to gender effect.
Topics: Humans; Male; Female; Spiral Cone-Beam Computed Tomography; Imaging, Three-Dimensional; Oropharynx; Cone-Beam Computed Tomography; Epiglottis; Cephalometry; Pharynx
PubMed: 37815391
DOI: 10.1097/SCS.0000000000009768 -
The Journal of Infectious Diseases Nov 2023Adding additional specimen types (eg, serology or sputum) to nasopharyngeal swab (NPS) reverse transcription polymerase chain reaction (RT-PCR) increases respiratory... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Adding additional specimen types (eg, serology or sputum) to nasopharyngeal swab (NPS) reverse transcription polymerase chain reaction (RT-PCR) increases respiratory syncytial virus (RSV) detection among adults. We assessed if a similar increase occurs in children and quantified underascertainment associated with diagnostic testing.
METHODS
We searched databases for studies involving RSV detection in persons <18 years using ≥2 specimen types or tests. We assessed study quality using a validated checklist. We pooled detection rates by specimen and diagnostic tests and quantified performance.
RESULTS
We included 157 studies. Added testing of additional specimens to NP aspirate (NPA), NPS, and/or nasal swab (NS) RT-PCR resulted in statistically nonsignificant increases in RSV detection. Adding paired serology testing increased RSV detection by 10%, NS by 8%, oropharyngeal swabs by 5%, and NPS by 1%. Compared to RT-PCR, direct fluorescence antibody tests, viral culture, and rapid antigen tests were 87%, 76%, and 74% sensitive, respectively (pooled specificities all ≥98%). Pooled sensitivity of multiplex versus singleplex RT-PCR was 96%.
CONCLUSIONS
RT-PCR was the most sensitive pediatric RSV diagnostic test. Adding multiple specimens did not substantially increase RSV detection, but even small proportional increases could result in meaningful changes in burden estimates. The synergistic effect of adding multiple specimens should be evaluated.
Topics: Adult; Child; Humans; Respiratory Syncytial Virus Infections; Sensitivity and Specificity; Respiratory Syncytial Virus, Human; Viruses; Diagnostic Techniques and Procedures; Nasopharynx; Reverse Transcriptase Polymerase Chain Reaction
PubMed: 37285396
DOI: 10.1093/infdis/jiad185 -
Trends in Microbiology Aug 2023The nasopharynx is an important microbial reservoir for the emergence and spread of antibiotic-resistant organisms. The nasopharyngeal resistome is an extensive,... (Review)
Review
The nasopharynx is an important microbial reservoir for the emergence and spread of antibiotic-resistant organisms. The nasopharyngeal resistome is an extensive, adaptable reservoir of antibiotic-resistance genes (ARGs) within this niche. Metagenomic sequencing decodes the genetic material of all organisms within a sample using next-generation technologies, permitting unbiased discovery of novel ARGs and associated mobile genetic elements (MGEs). The challenges of sequencing a low-biomass bacterial sample have limited exploration of the nasopharyngeal resistome. Here, we explore the current understanding of the nasopharyngeal resistome, particularly the role of MGEs in propagating antimicrobial resistance (AMR), explore the advantages and limitations of metagenomic sequencing technologies and bioinformatic pipelines for nasopharyngeal resistome analysis, and highlight the key outstanding questions for future research.
Topics: Humans; Anti-Bacterial Agents; Bacteria; Drug Resistance, Microbial; Genes, Bacterial; Nasopharynx; Metagenomics
PubMed: 36967247
DOI: 10.1016/j.tim.2023.02.008 -
Nature Communications Nov 2023Even slight imbalance between the growth rate of different organs can accumulate to a large deviation from their appropriate size during development. Here, we use live...
Even slight imbalance between the growth rate of different organs can accumulate to a large deviation from their appropriate size during development. Here, we use live imaging of the pharynx of C. elegans to ask if and how organ size scaling nevertheless remains uniform among individuals. Growth trajectories of hundreds of individuals reveal that pharynxes grow by a near constant volume per larval stage that is independent of their initial size, such that undersized pharynxes catch-up in size during development. Tissue-specific depletion of RAGA-1, an activator of mTOR and growth, shows that maintaining correct pharynx-to-body size proportions involves a bi-directional coupling between pharynx size and body growth. In simulations, this coupling cannot be explained by limitation of food uptake alone, and genetic experiments reveal an involvement of the mechanotransducing transcriptional co-regulator yap-1. Our data suggests that mechanotransduction coordinates pharynx growth with other tissues, ensuring body plan uniformity among individuals.
Topics: Humans; Animals; Caenorhabditis elegans; Pharynx; Mechanotransduction, Cellular; Caenorhabditis elegans Proteins; YAP-Signaling Proteins
PubMed: 37985670
DOI: 10.1038/s41467-023-43230-1 -
Sleep & Breathing = Schlaf & Atmung May 2024The aim of this study was to evaluate the efficacy of uvulopalatopharyngoplasty (UPPP) and the corresponding postoperative morphometrical changes.
OBJECTIVES
The aim of this study was to evaluate the efficacy of uvulopalatopharyngoplasty (UPPP) and the corresponding postoperative morphometrical changes.
METHODS
Patients diagnosed with obstructive sleep apnea syndrome who complained of snoring and apnea were enrolled in this study. Pre- and postoperative tests, including CTs, pharyngeal volume (PV), cross-sectional area (CSA), and six-category morphometrical studies, were performed.
RESULTS
Of 11 patients included, 10 showed improvement of symptoms. BMI correlated with the respiratory event index (REI). In terms of PV, there was a significantly wider postoperative area. The rate of change between preoperative REI and postoperative REI (ΔREI) correlated with the amount of change of PV between preoperative PV and postoperative PV (ΔPV). CSA increased postoperatively and correlated with REI. Uvula space (UV) and distance between the hyoid bone and the base of the tongue (HB) increased postoperatively, and posterior airway space (PAS) and epiglottic space (Epi) decreased postoperatively. UV and PAS were significant (p = 0.046, 0.014). UV was related to REI.
CONCLUSION
Widening the PV, increasing CSA, and the posterior movement of the tongue base after UPPP surgery were found. The improvement of REI did not depend only on volume. These results suggest that it was important not only to widen the PV but also to improve the shape of the pharynx.
Topics: Humans; Sleep Apnea, Obstructive; Uvula; Pharynx; Male; Female; Middle Aged; Adult; Polysomnography; Otorhinolaryngologic Surgical Procedures; Palate, Soft
PubMed: 37792164
DOI: 10.1007/s11325-023-02926-w