Epidemiology of acute otitis media among young children: a multiple database study in Taiwan

Effects of reactive oxygen species generation induced by Wonju City particulate matter on mitochondrial dysfunction in human middle ear cell

Atmospheric particulate matter (PM) contains different components that can elicit varying adverse health effects in humans and animals. Studies on PM toxicity and its underlying mechanisms in the middle ear are limited, and they generally use a PM standard. However, as PM composition varies temporally and geographically, it is crucial to identify the toxic PM constituents according to season and region and investigate their associated health effects. Thus, we sought to determine whether PM induces cytotoxicity and inflammatory factor and reactive oxygen species (ROS) generation in human middle ear epithelial cells obtained from patients with otitis media. The cells were treated with both standard urban PM and PM directly captured from the atmosphere in Wonju City. The association between mitochondrial dysfunction and PM was investigated. PM exposure significantly increased COX-2 and TNF-α mRNA expression, increased ROS generation, induced inflammatory responses, and caused abnormalities in mitochondrial motility and function. Furthermore, PM induced cell apoptosis, which consequently reduced cell survival, particularly at the concentration of 100 μg/mL. Overall, our study provides new insights into the toxic effects of standard and atmospheric PM on middle ear cell line.

Engineering of Extracellular Vesicles Based on Payload Changes for Tissue Regeneration

In the field of tissue regeneration and tissue engineering, many years ago, various nano to macroscopic-sized materials have been used to reduce inflammation and restore damaged tissue. Whether it is safe to study the regeneration of all tissues based on the biological mechanisms of an organism composed of cells is still debated, and studies using extracellular vesicles derived from cells have become popular in the past decade. It has been reported that exosomes with a size of 100 nm or less, which plays an important role in cell-cell communication, contain various factors, such as proliferation, anti-inflammatory, and growth factors. In addition, the payload of exosomes varies depending on the parent cell and the recipient cell, and a technology to differentiate the selective payload must treat specific diseases. In this review, we examined the current trends in research using exosomes derived from cells or tissues and analyzed various research reports on factors that can affect tissue regeneration.

Alteration of payload in extracellular vesicles by crosstalk with mesenchymal stem cells from different origin

Background

The application of extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) requires customized materials to target disease or cell damage. We hypothesized that EVs exert different inflammatory effects on one recipient cell, although stem cells of different origins in humans have similar payloads.

Results

Here, the payload of EVs released by crosstalk between MSCs and human middle ear epithelial cells (HMEECs) extracted from adipose tissue, bone marrow and tonsils significantly increased the level of anti-inflammatory factors. EVs derived from the co-culture medium decreased TNF-, COX-2, IL-1, and IL-6 levels to approximately zero within 3h in HMEECs. Expression of miR-638 and amyloid- A4 precursor protein-binding family A member 2 was analyzed using microarrays and gene ontology analysis, respectively.

Conclusions

In conclusion, stem cells of different origins have different payloads through crosstalk with recipient-specific cells. Inducing specific factors in EVs by co-culture with MSCs could be valuable in regenerative medicine.

Graphical abstract

Trends and health burden of hospitalized acute respiratory infections and impact of Haemophilus influenza immunization in a Tunisian university hospital: a twelve-year study

BACKGROUND

We aimed to describe the episodes and trends of admissions for community-acquired Respiratory Infections (RI) over a 12-year period and to assess the impact of Haemophilus influenza type b (Hib) vaccine on RI admissions in children aged up to 3 years.

METHODS

We conducted a twelve-year retrospective observational study on all community-acquired RI admitted to Fattouma Bourguiba Hospital in Monastir Governorate (Tunisia) from 1 January 2002 to 31 December 2013. RI cases were selected from the Regional Registry of Hospital Morbidity. Data were coded according to ICD-10. To assess the impact of the Hib vaccine, three cohorts were defined based on vaccine status (unvaccinated cohort, first vaccinated cohort (VC) by monovalent form and second VC by pentavalent combination).

RESULTS

Admissions for RI represented 17.6% (CI95%: 17.3-18.1) of all communicable diseases hospitalizations (n = 6 061/34 289). The crude incidence rates (CIR) per 100,000 inh were 24.2 for upper RI (URI) and 77.5 and for Lower RI (LRI) (p < 0.0001). Pneumonias represented 53.9% of LRI. Sex-ratio (male/female) was 1.12 for URI and 1.64 for LRI (p < 0.0001). At admission, the median age was 22 years (IQR: 3-52). Admission for Pneumonia increased significantly during study period (slope 'b' = 5.16; p < 0.0001) especially in children up to 5 years old (slope 'b' = 5.53) and in elderly (slope 'b' = 2.13). Among children up to 3 years old, the CIRs per 100,000 for Hib pneumonia admission were 11.6 in Non-Vaccinated Cohort (NVC), 10.6 in Vaccinated Cohort (VC) by protocol 1 (Hib Vaccine monovalent) and 0.80 in VC by protocol 2 (pentavalent vaccine combination).The relative risk reduction was 99% for protocol 2 (p < 0.001).

CONCLUSION

Admissions for RI in a  tertiary level hospital were common with an increasing trend. The Hib immunization program, in particular the pentavalent combination, has had a positive impact on the reduction of related acute diseases.

Childhood otitis media: Relationship with daycare attendance, harsh parenting, and maternal mental health

Psychological stress has been linked to developmental problems and poor health in children, but it is unclear whether it is also related to otitis media (OM). As part of a long-term study surveying the characteristics of childcare and development in Taiwan, we analyzed the relationship between OM and sources of psychological stress in children, such as poor maternal mental health and harsh parental discipline. We analyzed the data of 1998 children from the "Kids in Taiwan: National Longitudinal Study of Child Development & Care (KIT) Project" at the age of 3 years. Using bivariate and multivariate logistic regression models, we tested several risk factors as potential independent predictors of two outcomes: parent-reported incidence of OM and child health. The proportion of children who had developed OM in the first 3 years of their life was 12.5%. Daycare attendance (odds ratio [OR]: 1.475; 95% confidence interval [CI]: 1.063-2.046), poor maternal mental health (OR: 1.913; 95% CI: 1.315-2.784), and harsh parental discipline (OR: 1.091; 95% CI: 1.025-1.161) correlated with parent-reported occurrence of OM. These findings suggest that providing psychosocial support to both parents and children might be a novel strategy for preventing OM.

Quercetin inhibits NTHi-triggered CXCR4 activation through suppressing IKKα/NF-κB and MAPK signaling pathways in otitis media

Otitis media is one of the most common bacterial infections in children, contributing to hearing loss. A vital bacterial pathogen leading to otitis media development is the nontypeable Haemophilus influenzae (NTHi). Inflammation response is reported as an important characristic for otitis media. Chemokine CXC receptor 4 (CXCR4) is a 352-amino acid seven-span transmembrane G-protein coupled receptor, essential for inflammatory response. However, the possible molecular mechanism indicating the alteration of CXCR4 modulated by NTHi is poorly known. In the present study, NTHi enhanced CXCR4 expression through phosphorylation of IKKα and p38, which relied on nuclear factor-κB (NF-κB) translocation in vitro as well as in the middle ear of mice in vivo. Previously, quercetin, a natural production mainly isolated from rutin, has shown anti-inflammatory effects. Here, we report that quercetin suppressed NTHi-induced CXCR4 expression levels in vitro and in vivo. Quercetin blocked CXCR4 activation through direct IKKβ phosphorylation inhibition, as well as of p38 MAPK restraining. Hence, identification of quercetin may be a potential therapeutic strategy for treating otitis media induced by NTHi through inflammation suppression.

Systemic corticosteroids for acute otitis media in children

BACKGROUND

Acute otitis media (AOM) is a common acute infection in children. Pain is its most prominent and distressing symptom. Antibiotics are commonly prescribed for AOM, although they have only a modest effect in reducing pain at two to three days. There is insufficient evidence for benefits of other treatment options, including systemic corticosteroids. However, systemic corticosteroids are potent anti-inflammatory drugs, and so theoretically could be effective, either alone or as an addition to antibiotics.

OBJECTIVES

To assess the effects of systemic corticosteroids (oral or parenteral), with or without antibiotics, for AOM in children.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) which contains the Cochrane ARI Group's Specialised Register, MEDLINE (Ovid), Embase (Elsevier), CINAHL (EBSCO), Web of Science (Thomson Reuters), and LILACS (BIREME) for published studies, and ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) for completed and ongoing studies, to 20 February 2018. We checked the reference lists of all primary studies and review articles for additional references and contacted experts in the field to identify additional unpublished materials.

SELECTION CRITERIA

We included randomised controlled trials of children with AOM that compared any systemic corticosteroid (oral or parenteral) with placebo, either with antibiotics (corticosteroid plus antibiotic versus placebo plus antibiotic) or without antibiotics (corticosteroid versus placebo).

DATA COLLECTION AND ANALYSIS

Three review authors (EDS, RR, YP) independently screened the titles and abstracts and retrieved the full texts of potentially relevant studies. We independently extracted study characteristics and outcome data from the included studies, and assessed the risk of bias for each study using the criteria outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We assessed study quality using the GRADE method.

MAIN RESULTS

We included two studies involving 252 children with AOM aged from three months to six years receiving hospital ambulatory care who were treated with intramuscular ceftriaxone, and who were then randomised to the corticosteroid group (corticosteroid and corticosteroid plus antihistamine) or the placebo group (antihistamine and double placebo). In one study, children also had a needle aspiration of middle ear fluid. Both studies were at unclear risk of bias for allocation concealment, and unclear to high risk of bias for selective reporting.One study (N = 179) included pain as an outcome, but we were unable to derive the proportion of children with persistent pain at Day 5 and Day 14. Reduction of overall or specific symptoms was presented as improvement in clinical symptoms and resolution of inflamed tympanic membranes without the need for additional antibiotic treatment: at Day 5 (94% of children in the treatment group (N = 89) versus 89% in the placebo group (N = 90); risk ratio (RR) 1.06, 95% confidence interval (CI) 0.97 to 1.16) and Day 14 (91% versus 87%; RR 1.05, 95% CI 0.95 to 1.17). Low-quality evidence meant that we are uncertain of the effectiveness of corticosteroids for this outcome.The second study (N = 73) reported a reduction of overall or specific symptoms without additional antibiotic treatment during the first two weeks as a favourable outcome. Children in the treatment group had more favourable outcomes (adjusted odds ratio 65.9, 95% CI 1.28 to 1000; P = 0.037), although the numbers were small. We were unable to pool the results with the other study because it did not report the proportion of children with this outcome by treatment group. Only one study reported adverse effects of corticosteroids (e.g. drowsiness, nappy rash), but did not quantify incidence, so we were unable to draw conclusions about adverse effects. Neither study reported a reduction in overall or specific symptom duration.

AUTHORS' CONCLUSIONS

The evidence for the effect of systemic corticosteroids on AOM is of low to very low quality, meaning the effect of systemic corticosteroids on important clinical outcomes in AOM remains uncertain. Large, high-quality studies are required to resolve the question.

Notch signaling is active in normal mouse middle ear epithelial cells

Mucous cell metaplasia/hyperplasia in the middle ear epithelium is associated with the occurrence of otitis media with effusion during infections. However, the mechanism by which Notch signaling regulates cell fate in the middle ear epithelium is unclear. The aim of the present study was to elucidate this mechanism by investigating the localization of Notch receptors, such as Notch1 and Notch2, and Notch ligands, such as Jagged1, in the normal mouse middle ear epithelium (NMMEE) using immunofluorescence. Furthermore, the mRNA expression levels of Notch receptors and ligands were evaluated using reverse transcription polymerase chain reaction (PCR). The effects of the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine tert-butyl ester (DAPT) on epithelial cell proliferation were determined using 5-ethynyl-2′-deoxyuridine (EdU) staining and immunofluorescence staining of the apoptosis marker caspase-3 and the epithelial proliferation marker pan-cytokeratine. In addition, the differentiation of the NMMEE cells was characterized by evaluating the mRNA expression levels of the mucous cell-associated genes Arg2, Muc2, Spdef, Spink4 and Tff1 using quantitative PCR. Notch1, Notch2 and Jagged1 were observed to be co-localized throughout the mouse middle ear epithelium. Furthermore, Notch1-4, Jagged1, Jagged2, Dll1 and Dll4 mRNAs were expressed in the NMMEE cells. The inhibition of Notch by DAPT resulted in fewer EdU-positive cells and the upregulation of the expression levels of various mucous cell-associated genes. The results indicate that DAPT suppresses the proliferation of NMMEE cells while promoting their differentiation into mucous cells. Therefore, DAPT may provide a specific therapeutic strategy for the reversal of multiple pathological processes that are associated with epithelium thickening in the middle ear.

A test protocol for assessing the hearing status of students with special needs

OBJECTIVES

Individuals with disabilities are often reported to have a high prevalence of undetected hearing disorders/loss, but there is no standardized hearing test protocol for this population. The purposes of this study were (1) to examine the hearing status of students with special needs in Taiwan, and (2) to investigate the use of an on-site hearing test protocol that would adequately detect hearing problems in this population and reduce unnecessary referrals for off-site follow-up services.

METHODS

A total of 238 students enrolled in two schools for special education and one habilitation center participated in the study. Most students had intellectual disabilities and some also had additional syndromes or disorders. A hearing screening protocol including otoscopy, tympanometry, and distortion product otoacoustic emissions was administered to examine students' outer, middle, and inner ear functions, respectively. Pure tone tests were then administered as an on-site follow-up for those who failed or could not be tested using the screening protocol.

RESULTS

Only 32.4% of students passed. When administered alone, the referral rate of otoscopy, tympanometry, and otoacoustic emissions were 38.7%, 46.0%, and 48.5%, respectively. The integration of these subtests revealed 52.1% of students needed follow-up services, 11.8% could not be tested, 2.5% had documented hearing loss, and 1.3% needed to be monitored because of negative middle ear pressure. The inclusion of pure tone audiometry increased the passing rate by 9.9% and provided information on hearing sensitivity for an additional 8.6% of students.

CONCLUSION

Hearing assessments and regular hearing screening should be provided as an integral part of health care services for individuals with special needs because of high occurrences of excessive cerumen, middle ear dysfunction, and sensorineural hearing loss. The training of care-givers and teachers of students with special needs is encouraged so that they can help identify hearing problems and reduce the negative impact of hearing disorders and hearing loss. The screening protocol needs to include subtests that examine the status of different parts of their auditory system. The addition of pure tone audiometry as an on-site follow-up tool reduced the rate of off-site referrals and provided more information on hearing sensitivity.

Conductive and Mixed Hearing Losses: A Comparison between Summer and Autumn

Background and Objectives

Conductive hearing loss is common among children and adults. This study aims at comparing the results of conductive hearing loss in summer and autumn.

Subjects and Methods

Puretone audiometry and tympanometry tests were done for all patients who referred to the Iranian-based audiology center of Imam Khomeini Hospital in Ahvaz. Data on the patients with conductive or mixed hearing loss were analyzed. The impacts of season, age, and etiology of the disease were analyzed on the patients who visited the audiology clinic due to the conductive hearing loss in summer and autumn.

Results

One hundred and fifty nine patients in summer and 123 patients in autumn had conductive or mixed hearing loss. Their age ranged from four to 82 years, with the average age of 35. The percentage of the patients, with acute otitis media and chronic otitis media (COM), who visited this clinic, was significantly higher than those with middle ear problems. COM and mastoid surgeries rate was higher in summer than autumn among adults.

Conclusions

There is no relationship between season and middle ear diseases between children and juveniles, but COM and mastoid problems are more common in summer among adults visiting this clinic. Most of the patients had mild conductive hearing loss and bilateral middle ear impairments.

Effect of urban particles on human middle ear epithelial cells

OBJECTIVES

The aim of this study was to examine the cytotoxic effect and inflammatory response of human middle ear epithelial cells (HMEECs) induced by urban particles (UP).

MATERIALS AND METHODS

Cell viability following UP exposure was assessed in HMEECs using the CCK 8 assay. The expression levels of the inflammation-related genes (COX-2 and MUC5AC) were analyzed using semi-quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and COX-2 production was analyzed using western blotting.

RESULTS

Treatment with UP decreased cell viability in HMEECs in a dose- and time-dependent manner. UP exposure induced the significantly increased expression of COX-2 and MUC5AC. Western blotting showed dose dependently increased expression of COX-2 production.

CONCLUSIONS

UP decreased cell viability, increased the inflammatory response, and increased mucin gene production in HMEECs. These findings indicate that exposure to UP can contribute to the development of otitis media.

Bacterial etiology of acute otitis media in the era prior to universal pneumococcal vaccination in Taiwanese children

BACKGROUND

Acute otitis media (AOM) is one of the most frequent bacterial infections in children. Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi) are the two major bacterial pathogens. Pneumococcal conjugate vaccine was introduced into Taiwan in 2005 and only some children were vaccinated. This retrospective study assessed the bacterial etiology of AOM and its antimicrobial susceptibility in the era prior to universal pneumococcal vaccination in Taiwan.

METHODS

From December 2009 to November 2011, children presenting with AOM and having a middle ear effusion sample collected by tympanocentesis were enrolled. The study period was divided into two parts. Demographic data of patients and antibiotic susceptibility of the pathogens were collected and analyzed. Serotypes of S. pneumoniae were identified.

RESULTS

Among the 151 episodes, 46% of samples found bacterial pathogens. S. pneumoniae and NTHi were the leading causes of AOM, detected in 55.7% and 22.9% of bacterial AOM episodes, respectively. The prevalent serotypes of S. pneumoniae were 19 A and 19 F. Significantly more pneumococcal and serotype 19 A AOM were found in the later study period (18.4% vs. 33.3%, p = 0.0036; 10.5% vs. 24.0%, p = 0.028). Among the 39 S. pneumoniae isolates, 11 strains (28.2%) were penicillin-susceptible. Of the 16 NTHi, 10 (62.5%) were susceptible to amoxicillin/clavulanate and all were susceptible to cefotaxime.

CONCLUSION

S. pneumoniae and NTHi were the leading causes of AOM in Taiwanese children in the study period. An increase in patient numbers and proportion of pneumococcal and serotype 19 A AOM occurred. Antimicrobial nonsusceptibility was common in the predominant pathogens.