Underlying Glycans Determine the Ability of Sialylated Lipooligosaccharide To Protect Nontypeable Haemophilus influenzae from Serum IgM and Complement Molecular Pathogenesis

Nontypeable Haemophilus influenzae (NTHi) efficiently colonizes the human nasopharynx asymptomatically but also causes respiratory mucosal infections, including otitis media, sinusitis, and bronchitis. The lipooligosaccharide (LOS) on the cell surface of NTHi displays complex glycans that mimic host structures, allowing it to evade immune recognition. However, LOS glycans are also targets of host adaptive and innate responses. To aid in evasion of these responses, LOS structures exhibit interstrain heterogeneity and are also subject to phase variation, the random on/off switching of gene expression, generating intrastrain population diversity. Specific LOS modifications, including terminal sialylation of the LOS, which exploits host-derived sialic acid (Neu5Ac), can also block recognition of NTHi by bactericidal IgM and complement by mechanisms that are not fully understood. We investigated the LOS sialic acid-mediated resistance of NTHi to antibody-directed killing by serum complement. We identified specific LOS structures extending from heptose III that are targets for binding by naturally occurring bactericidal IgM in serum and are protected by sialylation of the LOS. Phase-variable galactosyltransferases encoded by lic2A and lgtC each add a galactose epitope bound by IgM that results in antibody-dependent killing via the classical pathway of complement. NTHi’s survival can be influenced by the expression of phase-variable structures on the LOS that may also depend o...
Source: Infection and Immunity - Category: Infectious Diseases Authors: Tags: Molecular Pathogenesis Source Type: research

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ConclusionThe COMQ-12 could be a useful tool to differentiate chronic otitis media with or without cholesteatoma.
Source: European Archives of Oto-Rhino-Laryngology - Category: ENT & OMF Source Type: research
AbstractPurpose of ReviewLymphatic disorders have received an increasing amount of attention over the last decade. Sparked primarily by improved imaging modalities and the dawn of lymphatic interventions, understanding, diagnostics, and treatment of lymphatic complications have undergone considerable improvements. Thus, the current review aims to summarize understanding, diagnostics, and treatment of lymphatic complications in individuals with congenital heart disease.Recent FindingsThe altered hemodynamics of individuals with congenital heart disease has been found to profoundly affect morphology and function of the lymph...
Source: Current Cardiology Reports - Category: Cardiology Source Type: research
AbstractEndoscopic Sinus Surgery is evolving day by day, there is a constant need for improvisation in terms of instrumentation with clear bloodless surgical field and good postoperative results. The applications of Dr. Ahila ’s Conchal Crusher for managing Concha bullosa in Functional Endoscopic Sinus Surgery  (FESS) Surgery are presented. The creation/innovation of Dr. Ahila’s conchal crusher will prevent raw mucosal surface area, bleeding and scope fogging with blood during FESS surgery after traditional conchop lasty. This new instrument makes it easy to reduce concha bullosa during nose and sinus...
Source: Indian Journal of Otolaryngology and Head and Neck Surgery - Category: ENT & OMF Source Type: research
Conclusions: Medical history, physical examination, and imaging studies are crucial in the diagnosis of retinoblastoma-associated orbital pseudocellulitis. Retinoblastoma should be excluded in all patients with signs of pre-septal orbital cellulitis through fundoscopy and/or imaging studiesOcul Oncol Pathol
Source: Ocular Oncology and Pathology - Category: Opthalmology Source Type: research
CONCLUSIONS/SIGNIFICANCE: Otological and audiological outcomes in both groups were similar. The audiological prognosis was favorable regardless of the cleft palate condition. PMID: 33030069 [PubMed - as supplied by publisher]
Source: Acta Oto-Laryngologica - Category: ENT & OMF Authors: Tags: Acta Otolaryngol Source Type: research
Authors: Ciprandi G, La Mantia I, Damiani V, Passali D Abstract INTRODUCTION: Children with recurrent respiratory infections (RRI) represent a social issue for the economic burden and the negative family impact. Local Bacteriotherapy is an attractive therapeutic strategy that could be potentially effective in preventing infections. The current article remarks on the existing evidence of preventing RRI by Local Bacteriotherapy. AREAS COVERED: The literature search methodology was based on the articles cited by PubMed from 1980 to 2020. Respiratory infections include rhino-pharyngitis, otitis media, rhinosinusiti...
Source: Expert Review of Clinical Immunology - Category: Allergy & Immunology Tags: Expert Rev Clin Immunol Source Type: research
By KEN TERRY In a recent podcast about the future of telehealth, Lyle Berkowitz, MD, a technology consultant, entrepreneur, and professor at Northwestern University’s Feinberg School of Medicine, confidently predicted that, because of telehealth and clinical automation, “In 10-20 years, we won’t need primary care physicians [for routine care]. The remaining PCPs will specialize in caring for complicated patients. Other than that, if people need care, they’ll go to NPs or PAs or receive automated care with the help of AI.” Berkowitz isn’t the first to make this kind of predictio...
Source: The Health Care Blog - Category: Consumer Health News Authors: Tags: Artificial Intelligence Health Tech AI Ken Terry primary care Source Type: blogs
CONCLUSION: Chronic suppurative otitis media and otitis media sequelae were surprisingly uncommon in this sample of rural primary school children in Zimbabwe. More studies, preferably population-based, are needed to enable more precise estimates of chronic suppurative otitis media prevalence in Zimbabwe. PMID: 33016257 [PubMed - as supplied by publisher]
Source: Journal of Laryngology and Otology - Category: ENT & OMF Tags: J Laryngol Otol Source Type: research
Abstract Biofilms play a central role in the pathobiology of otitis media (OM), bronchitis, sinusitis, conjunctivitis, and pneumonia caused by nontypeable Haemophilus influenzae (NTHI). Our previous studies show that extracellular DNA (eDNA) and DNABII proteins are essential components of biofilms formed by NTHI. The DNABII protein family includes integration host factor (IHF) and the histone‐like protein HU and plays a central role in NTHI biofilm structural integrity. We demonstrated that immunological targeting of these proteins during NTHI‐induced experimental OM in a chinchilla model caused rapid clearance of biof...
Source: MicrobiologyOpen - Category: Microbiology Authors: Tags: ORIGINAL RESEARCH Source Type: research
CONCLUSION: This study provides, for the first time, information on flagellar expression in H. influenzae, representing an important finding related to its evolution and pathogenic potential. PMID: 28513418 [PubMed - as supplied by publisher]
Source: Journal of Medical Microbiology - Category: Microbiology Authors: Tags: J Med Microbiol Source Type: research
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