Twenty-four hour ambulatory nasal pH monitoring

Hehar, S. S.; Mason, J. D. T.; Stephen, A. B.; Washington, N.; Jones, Nicholas S.; Jackson, S.J; Bush, Debbie

doi:10.1046/j.1365-2273.1999.00190.x

Cited by 35 publications

(24 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus potentially, alterations in airway surface pH may explain many of the phenotypic hallmarks of CF and may lead to new treatment options. Airway surface pH has been previously measured in the nose, and both the equipment and methodology are well established [23,24]. Previous studies have reported that nasal pH varies with race [25] and the presence of rhinitis [26].…”

mentioning

confidence: 99%

Airway surface pH in subjects with cystic fibrosis

McShane¹,

Davies²,

Davies³

et al. 2003

Eur Respir J

115

View full text Add to dashboard Cite

The cystic fibrosis (CF) transmembrane conductance regulator protein can transport bicarbonate and may therefore regulate airway surface (AS) pH. Disturbances of AS pH could contribute to the pathophysiology of CF lung disease.Five studies were carried out including the following: study 1) nasal pH measurements were made in 25 CF and 10 non-CF adults using an antimony pH probe. Mean nasal pH was significantly lower in the CF group. Nasal potential difference may have been a confounding factor; study 2) in a fresh cohort of CF and non-CF subjects, no significant difference was found between the two groups using a gold pH probe; study 3) simultaneous nasal pH measurements were made in 15 CF and 15 non-CF adults using both probes. In the CF group, there was a trend for the antimony probe to read lower than the gold probe. In the non-CF group, the antimony probe read higher. The pH difference noted in study 1 related to technical factors; study 4) the effect of acute changes in serum acid/base balance on nasal pH was assessed in five non-CF adults. Nasal pH was not altered by either acute respiratory acidosis or alkalosis; study 5) nasal and lower airway pH was measured in five CF and six non-CF children. No difference was found between the groups. There was a correlation between nasal and lower airway pH.The authors conclude that airway surface pH does not differ between cystic fibrosis and noncystic fibrosis subjects and therefore, cystic fibrosis transmembrane conductance regulator may not play a major role in airway surface pHin vivo.

show abstract

mentioning

confidence: 99%

Airway surface pH in subjects with cystic fibrosis

McShane¹,

Davies²,

Davies³

et al. 2003

Eur Respir J

115

View full text Add to dashboard Cite

show abstract

“…To assess the consequence of pH on the integrity of nasal mucosal surface, drug solutions of different pH values ranging from 2 to 12 were applied to rat nasal mucosa whose pH is 7.39 and the outcomes verified that when pH ranged from 3 to 10, negligible magnitude of proteins and enzymes were released from cells, indicative of no cellular damages. On the other hand, if pH values were lower than 3 or higher than 10, damages were observed intracellularly and at membrane level (Costantino et al, 2007;Hehar et al, 1999;Litvyakova & Baraniuk, 2001). …”

Section: Phmentioning

confidence: 99%

Nasal-nanotechnology: revolution for efficient therapeutics delivery

2014

View full text Add to dashboard Cite

Context: In recent years, nanotechnology-based delivery systems have gained interest to overcome the problems of restricted absorption of therapeutic agents from the nasal cavity, depending upon the physicochemical properties of the drug and physiological properties of the human nose. Objective: The well-tolerated and non-invasive nasal drug delivery when combined with the nanotechnology-based novel formulations and carriers, opens the way for the effective systemic and brain targeting delivery of various therapeutic agents. To accomplish competent drug delivery, it is imperative to recognize the interactions among the nanomaterials and the nasal biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signaling involved in patho-biology of the disease under consideration. Methods: Quite a few systems have been successfully formulated using nanomaterials for intranasal (IN) delivery. Carbon nanotubes (CNTs), chitosan, polylactic-co-glycolic acid (PLGA) and PLGA-based nanosystems have also been studied in vitro and in vivo for the delivery of several therapeutic agents which shown promising concentrations in the brain after nasal administration. Results and conclusion: The use of nanomaterials including peptide-based nanotubes and nanogels (NGs) for vaccine delivery via nasal route is a new approach to control the disease progression. In this review, the recent developments in nanotechnology utilized for nasal drug delivery have been discussed.

show abstract

“…The degree of acidification of these surfaces in mammals varies depending on the distribution and activity of the submucosal glands. The pH of the human passageway has a range from 5.2 to 8.0 [13][14][15][16][17][18]. Therefore, the efficient infection of human URT cells requires a certain level of virus stability to acidic pH.…”

Section: Differences Between Human and Avian Influenza Virusesmentioning

confidence: 99%

Influenza vaccines manufacturing in continuous cell lines: problems and solutions

Romanova¹

2017

Microbiology Independent Research Journal (MIR Journal)

View full text Add to dashboard Cite

In order to decrease the morbidity and mortality caused by seasonal influenza outbreaks, several hundred million vaccine doses are produced worldwide each year. The predominant substrate for the production of the influenza vaccine today is fertilized hen's eggs. The substitution of the technology based on living organisms by the cell culture-based process offers many advantages, including easier scalability and reduced dependence on the availability of eggs. The African green monkey kidney and Madin Darby canine kidney cell lines support the efficient growth of influenza viruses of different subtypes and, therefore, are considered to be the two most promising alternative substrates for the production of the human influenza vaccine.However, the pH of endosomes in both of these cell lines is higher than the pH essential for triggering a conformational change of the hemagglutinin (HA) of human influenza viruses, which enables the viral-cellular membrane fusion. This mismatch gives rise to mutations in the HA that lead to an increase of the optimum pH of HA conformational change. As of a result of these mismatches, the HA, and consequently the whole virus, has reduced stability to low pH and elevated temperatures. The production of a vaccine from less stable virus will lead to an elevated HA content in the low pH conformation that can affect the safety, potency, infectivity, and protective efficacy of the final inactivated and live attenuated influenza vaccines.The main limitations of the cell line-based influenza vaccine technology and the possibilities to preserve the viral stability over the course of influenza vaccine production are discussed in the review.

show abstract

Twenty-four hour ambulatory nasal pH monitoring

Cited by 35 publications

References 5 publications

Airway surface pH in subjects with cystic fibrosis

Airway surface pH in subjects with cystic fibrosis

Nasal-nanotechnology: revolution for efficient therapeutics delivery

Influenza vaccines manufacturing in continuous cell lines: problems and solutions

Contact Info

Product

Resources

About