Host-to-Host Group A Streptococcus Transmission Causes Infection of the Lamina Propria but not Epithelium of the Upper Respiratory Tract in MyD88-Deficient Mice

2021 ◽  
Author(s):  
Dylan Minor ◽  
Jacob Cavon ◽  
Thea Johnson ◽  
Savannah Ontiveros ◽  
Daniel Gao ◽  
...  
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Lamina Propria ◽  
Respiratory Infection ◽  
Group A Streptococcus ◽  
Acute Infection ◽  
Upper Respiratory Tract ◽  
Host Group ◽  
Group A ◽  
Upper Respiratory

To understand protective immune responses against the onset of Group A Streptococcus respiratory infection, we investigated whether MyD88 KO mice were susceptible to acute infection through transmission. After commingling with mice that had intranasal GAS inoculation, MyD88 -/- recipient mice had increased GAS loads in the nasal cavity and throat that reached a mean throat colonization of 6.3 x 10 6 cfu/swab and mean GAS load of 5.2 x 10 8 cfu in the nasal cavity on day 7. Beyond day 7, MyD88 -/- recipient mice became moribund, with mean 1.6 x 10 7 cfu/swab and 2.5 x 10 9 cfu GAS in the throat and nasal cavity, respectively. Systemic GAS infection occurred a couple of days after the upper respiratory infection. GAS infects the lip, gingival sulcus of the incisor teeth, the lamina propria of the turbinate but not the nasal cavity and nasopharyngeal tract epithelia, and C57BL/6J recipient mice had no or low levels of GAS in the nasal cavity and throat. Direct nasal GAS inoculation of MyD88 -/- mice caused GAS infection mainly in the lamina propria of the turbinate. In contrast, C57BL/6J mice with GAS inoculation had GAS bacteria in the nasal cavity but not in the lamina propria of the turbinates. Thus, MyD88 -/- mice are highly susceptible to acute and lethal GAS infection through transmission, and MyD88 signaling is critical for protection of the respiratory tract lamina propria but not nasal and nasopharyngeal epithelia against GAS infection.

scholarly journals Group A Streptococcus Infection of the Nasopharynx Requires Proinflammatory Signaling through the Interleukin-1 Receptor

2020 ◽  
Vol 88 (10) ◽  
Author(s):  
Doris L. LaRock ◽  
Raedeen Russell ◽  
Anders F. Johnson ◽  
Shyra Wilde ◽  
Christopher N. LaRock
Keyword(s):  
Respiratory Tract ◽  
Group A Streptococcus ◽  
Interleukin 1 ◽  
Etiologic Agent ◽  
High Morbidity ◽  
Invasive Infection ◽  
Upper Respiratory Tract ◽  
Group A ◽  
Upper Respiratory ◽  
Neutrophil Response

ABSTRACT Group A Streptococcus (GAS) is the etiologic agent of numerous high-morbidity and high-mortality diseases. Infections are typically highly proinflammatory. During the invasive infection necrotizing fasciitis, this is in part due to the GAS protease SpeB directly activating interleukin-1β (IL-1β) independent of the canonical inflammasome pathway. The upper respiratory tract is the primary site for GAS colonization, infection, and transmission, but the host-pathogen interactions at this site are still largely unknown. We found that in the murine nasopharynx, SpeB enhanced IL-1β-mediated inflammation and the chemotaxis of neutrophils. However, neutrophilic inflammation did not restrict infection and instead promoted GAS replication and disease. Inhibiting IL-1β or depleting neutrophils, which both promote invasive infection, prevented GAS infection of the nasopharynx. Mice pretreated with penicillin became more susceptible to GAS challenge, and this reversed the attenuation from neutralization or depletion of IL-1β, neutrophils, or SpeB. Collectively, our results suggest that SpeB is essential to activate an IL-1β-driven neutrophil response. Unlike during invasive tissue infections, this is beneficial in the upper respiratory tract because it disrupts colonization resistance mediated by the microbiota. This provides experimental evidence that the notable inflammation of strep throat, which presents with significant swelling, pain, and neutrophil influx, is not an ineffectual immune response but rather is a GAS-directed remodeling of this niche for its pathogenic benefit.

Changes in the parameters of nasal breathing and parameters of the upper respiratory tract during orthognathic operations in patients with II and III skeletal class of jaw anomalies

2020 ◽  
pp. 22-27
Author(s):  
S.Sh. Gammadaeva ◽  
M.I. Misirkhanova ◽  
A.Yu. Drobyshev
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Nasal Septum ◽  
Cross Sectional Area ◽  
Upper Respiratory Tract ◽  
Sectional Area ◽  
Nasal Breathing ◽  
Cross Sectional ◽  
Skeletal Class ◽  
Upper Respiratory

The study analyzed the functional parameters of nasal breathing, linear parameters of the nasal aperture, nasal cavity and nasopharynx, volumetric parameters of the upper airways in patients with II and III skeletal class of jaw anomalies before and after orthognathic surgery. The respiratory function of the nose was assessed using a rhinomanometric complex. According to rhinoresistometry data, nasal resistance and hydraulic diameter were assessed. According to the data of acoustic rhinometry, the minimum cross-sectional area along the internal valve, the minimum cross-sectional area on the head of the inferior turbinate and nasal septum and related parameters were estimated. According to the CBCT data, the state of the nasal septum, the inferior turbinates, the nasal aperture, the state of the nasal cavity, and the linear values of the upper respiratory tract (nasopharynx) were analyzed. The patients were divided into 4 groups according to the classification of the patency of the nasal passages by

Photography and the flexible fibreoptic rhinolaryngoscope

1986 ◽  
Vol 100 (1) ◽  
pp. 41-46 ◽  
Author(s):  
J. M. Lancer
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Upper Respiratory Tract ◽  
Pathological Anatomy ◽  
Medical Practitioners ◽  
Upper Respiratory

SummaryDocumentation of normal and pathological anatomy is important to all medical practitioners. The ability to visualize and photograph the upper respiratory tract has been revolutionized by the advent of the flexible fibreoptic rhinolaryngoscope (FFRL), which demonstrates a one-instrument capability for the examination and photodocumentation of the ears, nasal cavity, nasopharynx, larynx, hypopharynx and trachea (Selkin, 1984). If a large natural maxillary ostium, or surgical window, is present, the antrum may also be examined.

scholarly journals Preventive and therapeutic role of nasal irrigation in management of acute respiratory disease during COVID-19 pandemic and beyond

2021 ◽  
pp. 58-64
Author(s):  
V. M. Svistushkin ◽  
Zh. T. Mokoyan
Keyword(s):  
Respiratory Tract ◽  
Nasal Cavity ◽  
Distribution Area ◽  
Upper Respiratory Tract ◽  
Saline Irrigation ◽  
Nasal Irrigation ◽  
Wide Range ◽  
Upper Respiratory ◽  
Nasal Saline Irrigation ◽  
Tract Infections

It has long been known, that nasal saline irrigation is a safe and effective method, which is routinely prescribed by otorhinolaryngologists to prevent and to treat a wide range of pathologies. There are a lot of publications on different irrigation techniques and methods. This literature review discusses the key parameters of nasal irrigation, including tonicity, pH, and the additional components, and explains how they affect the effectiveness of the procedure. The vast majority of available publications did not found any possible changes in the effectiveness of solutions with different pH close to neutral meaning. Whereas, the volume of the irrigated solution, increases the efficiency of the irrigation in direct proportion. Thus, the largest distribution area of the solute is noted when washing with a large volume of liquid. Nasal saline irrigation is an effective treatment option for patients with several acute and chronic diseases and for postoperative care after rhinosurgery. Moreover, nasal irrigation might be used as an effective non-specific method for prevention of acute upper respiratory tract infections. Irrigation of the nasal cavity reduces the mucus viscosity and promotes its faster elimination, along with pathogens fixed in it. Additionally, irrigation with isotonic saline solutions increases the hydration of the underlying water base, which enhances the frequency of ciliary beat and reduces the concentration of local inflammatory mediators. COVID-19 pandemic situation due to lack of any specific antiviral drugs dictates the necessity of an effective non-specific preventive option, which could be introduced worldwide. The so-called full volume lavage of the nasal cavity allows for better cleaning of the nasal cavity and effective moisturizing of the mucous membrane. It is the timely cleansing and moisturizing that are most important for maintaining the normal activity of the local protective mechanisms of the upper respiratory tract.

Significance of Quantitative Salivary Cultures for Group A and Non-group A β-Hemolytic Streptococci in Patients with Pharyngitis and in Their Family Contacts

PEDIATRICS ◽  
1979 ◽  
Vol 64 (6) ◽  
pp. 904-912
Author(s):  
Edward L. Kaplan ◽  
Robert Couser ◽  
Barbara Ballard Huwe ◽  
Carolyn Mckay ◽  
Lewis W. Wannamaker
Keyword(s):  
Antibody Response ◽  
Respiratory Tract ◽  
Group A Streptococci ◽  
Upper Respiratory Tract ◽  
C Reactive Protein ◽  
Throat Culture ◽  
Reactive Protein ◽  
Group A ◽  
Bona Fide ◽  
Upper Respiratory

One hundred ninety-six individuals, 86 with clinically overt pharyngotonsillitis and 110 of their clinically negative contacts were studied to evaluate the sensitivity and the specificity of quantitative saliva cultures for group A β-hemolytic streptococci. We also compared this technique with semiquantitative throat cultures as a means of isolating group A streptococci and of differentiating the streptococcal carrier state from patients with bona fide streptococcal upper respiratory tract infection as defmed by the presence of an antibody response. The data indicate that the throat culture is a more reliable means of identifying group A β-hemolytic streptococci in the upper respiratory tract than is the saliva culture. The converse is true for non-group A β-hemolytic streptococci; the saliva culture is a much better means for isolating these organisms. In individuals positive by both techniques we found good correlation between the degree of positivity of the saliva culture and the degree of positivity of the throat culture. Furthermore, while there was a definite trend for individuals with strongly positive cultures to demonstrate more often an antibody rise in either antistreptolysin O and/or antideoxynibonuclease B—indicating bona fide infection—this relationship was not sufficiently constant to provide a clear differentiation. This study also indicates that discordance (one positive, one negative) of simultaneous duplicate semiquantitative throat cultures is much more common among individuals who do not show an antibody response ("carriers") than among those with an antibody response (bona fide infection). This study confirms our previous observations suggesting that the presence of C-reactive protein in the serum of patients with a positive culture for group A streptococci and clinical signs and symptoms of pharyngitis is often an indication of true streptococcal upper respiratory tract infection, and that even with a positive saliva culture at the initial visit, a negative C-reactive protein is only infrequently (25%) associated with an antibody response.

Bacterial Infections of the Adult Upper Respiratory Tract

2019 ◽  
Author(s):  
Laura K Certain ◽  
Miriam B Barshak
Keyword(s):  
Respiratory Tract ◽  
Bacterial Infections ◽  
Respiratory Tract Infections ◽  
Respiratory Infections ◽  
Group A Streptococcus ◽  
The United States ◽  
Controlled Study ◽  
Upper Respiratory Tract ◽  
Upper Respiratory ◽  
Tract Infections

Upper respiratory tract infections are the most common maladies experienced by humankind.1 The majority are caused by respiratory viruses. A Dutch case-controlled study of primary care patients with acute respiratory tract infections found that viruses accounted for 58% of cases; rhinovirus was the most common (24%), followed by influenza virus type A (11%) and corona­viruses (7%). Group A streptococcus (GAS) was responsible for 11%, and 3% of patients had mixed infections. Potential pathogens were detected in 30% of control patients who were free of acute respiratory symptoms; rhinovirus was the most common.2 Given the increasing problem of antibiotic resistance and the increasing awareness of the importance of a healthy microbiome, antibiotic use for upper respiratory infections should be reserved for those patients with clear indications for treatment. A recent study of adult outpatient visits in the United States found that respiratory complaints accounted for 150 antibiotic prescriptions per 1,000 population annually, yet the expected “appropriate” rate would be 45.3 In other words, most antibiotic prescriptions for these complaints are unnecessary. Similarly, a study in the United Kingdom found that general practitioners prescribed antibiotics to about half of all patients presenting with an upper respiratory infection, even though most of these infections are viral.4 This review contains 5 figures, 16 tables, and 82 references. Keywords: infection, airway, sinusitis, otitis media, otitis externa, pharyngitis, epiglottitis, abscess

Measurement of Local Mass Transfer Coefficients in a Cast Model of the Human Upper Respiratory Tract

1986 ◽  
Vol 108 (1) ◽  
pp. 12-18 ◽  
Author(s):  
L. M. Hanna ◽  
P. W. Scherer
Keyword(s):  
Mass Transfer ◽  
Respiratory Tract ◽  
Nasal Cavity ◽  
Upper Respiratory Tract ◽  
Transfer Coefficients ◽  
Mass Transfer Coefficients ◽  
Local Mass ◽  
Local Mass Transfer ◽  
Cast Model ◽  
Upper Respiratory

Local mass transfer coefficients measured using the naphthalene sublimation technique in an acrylic cast model of the human upper respiratory tract are reported as the Sherwood numbers for the corresponding regions. A steady air flow rate of 12 L per min was used for all measurements. Values of the Sherwood number are seen to be highest in the nasal cavity and proximal nasopharynx while a minimum value occurs just downstream from the larynx. Local values of the Nusselt number obtained in the trachea and proximal nasal cavity assuming a complete heat and mass transfer analogy agree well with in-vivo physiological measurements. The mass transfer coefficients found can be incorporated into an analytical model of respiratory heat and water vapor transfer or into a model of pollutant gas uptake in the respiratory tract.

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