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1.
Int Wound J ; 20(1): 120-130, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35633295

ABSTRACT

The study aimed to evaluate the antibacterial efficacy of Lugol's solution 5% and Gentian violet 1% against methicillin-resistant Staphylococcus aureus (MRSA) biofilm in vivo. The bactericidal efficacy for treatment of MRSA-biofilm skin wound infection was tested in a murine model. Luciferase-tagged S. aureus Xen31, a MRSA-strain derived from S. aureus ATCC-3359130, was used for infection. Wounds were made in the skin of mice and infected with MRSA. The mice were treated with Lugol's solution and Gentian violet. Application of the antimicrobial agents started 24 hours post infection and was repeated daily for five-days. The antimicrobial effect on the biofilm bacteria was evaluated by measuring bioluminescence from MRSA daily for seven-days. Lugol's solution and Gentian violet showed a significant reduction in luminescent signals from the first assessment day to all subsequent days (P < .001). Lugol's solution and Gentian violet effectively eradicated MRSA in biofilm in vivo and could be alternatives or in addition to topical antibiotics when MRSA-biofilm wound infection is suspected.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Skin Diseases, Infectious , Soft Tissue Injuries , Wound Infection , Animals , Mice , Gentian Violet/therapeutic use , Staphylococcus aureus , Anti-Bacterial Agents/therapeutic use , Wound Infection/drug therapy , Soft Tissue Injuries/drug therapy , Biofilms
2.
Cell Tissue Bank ; 23(3): 417-440, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35000046

ABSTRACT

The application of 3D printing technologies fields for biological tissues, organs, and cells in the context of medical and biotechnology applications requires a significant amount of innovation in a narrow printability range. 3D bioprinting is one such way of addressing critical design challenges in tissue engineering. In a more general sense, 3D printing has become essential in customized implant designing, faithful reproduction of microenvironmental niches, sustainable development of implants, in the capacity to address issues of effective cellular integration, and long-term stability of the cellular constructs in tissue engineering. This review covers various aspects of 3D bioprinting, describes the current state-of-the-art solutions for all aforementioned critical issues, and includes various illustrative representations of technologies supporting the development of phases of 3D bioprinting. It also demonstrates several bio-inks and their properties crucial for being used for 3D printing applications. The review focus on bringing together different examples and current trends in tissue engineering applications, including bone, cartilage, muscles, neuron, skin, esophagus, trachea, tympanic membrane, cornea, blood vessel, immune system, and tumor models utilizing 3D printing technology and to provide an outlook of the future potentials and barriers.


Subject(s)
Bioprinting , Bone and Bones , Ink , Printing, Three-Dimensional , Tissue Engineering , Tissue Scaffolds
3.
Ups J Med Sci ; 125(3): 217-225, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32552165

ABSTRACT

Background: Increasing antimicrobial resistance to antibiotics is a substantial health threat. Bioactive glass S53P4 (BAG) has an antimicrobial effect that can reduce the use of antibiotics. The aim of this study was to evaluate the antimicrobial efficacy of BAG in vitro on staphylococci in biofilm and in planktonic form. Secondary aims were to investigate whether supernatant fluid primed from BAG retains the antibacterial capacity and if ciprofloxacin enhances the effect.Methods: BAG-S53P4 granules, <45 µm, primed in tryptic soy broth (TSB) were investigated with granules present in TSB (100 mg/mL) and after removal of granules (100, 200, and 400 mg/mL). The efficacy of BAG to eradicate Staphylococcus aureus biofilm in vitro was tested using 10 different clinical strains and 1 reference strain in three test systems: the biofilm-oriented antiseptic test based on metabolic activity, the biofilm bactericidal test based on culturing surviving bacteria, and confocal laser scanning microscopy (CLSM) combined with LIVE/DEAD staining.Results: Exposure to 48 h primed BAG granules (100 mg/mL) produced bactericidal effects in 11/11 strains (p = 0.001), and CLSM showed reduction of viable bacteria in biofilm (p = 0.001). Supernatant primed 14 days, 400 mg/mL, reduced metabolic activity (p < 0.001), showed bactericidal effects for 11/11 strains (p = 0.001), and CLSM showed fewer viable bacteria (p = 0.001). The supernatant primed for 48 h, or in concentrations lower than 400 mg/mL at 14 days, did not completely eradicate biofilm.Conclusion: Direct exposure to BAG granules, or primed supernatant fluid, effectively eradicated S. aureus in biofilm. The anti-biofilm effect is time- and concentration-dependent. When BAG had reached its full antimicrobial effect, ciprofloxacin had no additional effect.


Subject(s)
Biofilms/drug effects , Glass , Plankton/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests
4.
Otol Neurotol ; 41(4): 537-544, 2020 04.
Article in English | MEDLINE | ID: mdl-32176145

ABSTRACT

OBJECTIVE: We compared the sound transmission using different types of total ossicular replacement prostheses (TORP); we then studied the performance of a new TORP that we designed inspired by the columella, the single ossicle found in birds. METHODS: Stapedial vibrations were measured on nine freshly frozen human temporal bones with laser Doppler vibrometry. We then compared the performances of eight common TORP positions or designs as well as the new silver prototype of bird-type prosthesis, designed also according to our digital holography patterns of the human tympanic membrane (TM). RESULTS: The TORPs placed in lateral contact with both the TM and the malleus handle outperformed, at most frequencies, those placed only in contact with the TM.The new bird-type prosthesis performed equally well or better than all other prostheses. CONCLUSION: If the malleus handle can be retained when placing a TORP, the best sound transmission can be achieved by placing the TORP in contact with both the distal part of the malleus handle and the TM. The good performance of our bird-type prosthesis suggests that there is still room for future improvement of prosthesis design to further optimize hearing outcomes after surgery.


Subject(s)
Ossicular Prosthesis , Ossicular Replacement , Humans , Lasers , Malleus/surgery , Temporal Bone/diagnostic imaging , Temporal Bone/surgery
5.
Otol Neurotol ; 41(1): 45-51, 2020 01.
Article in English | MEDLINE | ID: mdl-31664003

ABSTRACT

BACKGROUND: A significant number of adults suffer from conductive hearing loss due to chronic otitis media, otosclerosis, or other pathologies. An objective measurement of ossicular mobility is needed to avoid unnecessarily invasive middle ear surgery and to improve hearing outcomes. METHODS: Minimally invasive intraoperative laser vibrometry provides a method that is compatible with middle ear surgery, where the tympanic membrane is elevated. The ossicles were driven by a floating mass transducer and their mobility was measured using a laser Doppler vibrometer. Utilising this method, we assessed both the absolute velocities of the umbo and incus long process as well as the incus-to-umbo velocity ratio during artificial fixation of the incus alone or incus and malleus together. RESULTS: The reduction of absolute velocities was 8 dB greater at the umbo and 17 dB at the incus long process for incus-malleus fixations when compared with incus fixation alone. Incus fixation alone resulted in no change to the incus-to-umbo velocity ratio where incus-malleus fixations reduced this ratio (-11 dB). The change in incus velocity was shown to be the most suitable parameter to distinguish between incus fixation and incus-malleus fixation. When the whole frequency range was analyzed, one could also differentiate these two fixations from previously published stapes fixation, where the higher frequencies were less affected. CONCLUSION: Minimally invasive intraoperative laser vibrometry provides a promising objective analysis of ossicular mobility that would be useful intraoperatively.


Subject(s)
Ear Ossicles , Hearing Loss, Conductive/surgery , Lasers , Otologic Surgical Procedures/methods , Vibration , Adult , Ear Ossicles/pathology , Ear Ossicles/surgery , Female , Humans , Minimally Invasive Surgical Procedures/instrumentation , Minimally Invasive Surgical Procedures/methods , Models, Anatomic
6.
Otol Neurotol ; 40(1): e32-e39, 2019 01.
Article in English | MEDLINE | ID: mdl-30540698

ABSTRACT

OBJECTIVES: Patients with otosclerosis more often complain about postoperative taste disturbance than patients with chronic otitis media, which seems paradoxical. We aim to investigate if and potentially why this seems to be the case, since the chorda tympani nerve (CTN) is thought to be severely traumatized less frequently during surgery in the former than in the latter. STUDY DESIGN: Prospective cohort study. SETTING: Department of Otorhinolaryngology at Hospital of Vastmanland, Vasteras, Sweden. PATIENTS: Sixty-five adults undergoing primary middle ear surgery were included. Thirty-seven were operated on for chronic suppurative otitis media with or without cholesteatoma (CSOM) and 28 for otosclerosis. INTERVENTIONS: Middle ear surgery due to otosclerosis or CSOM. Subjective and objective taste measurements and quality of life (QoL) questionnaire. MAIN OUTCOME MEASURES: Taste was assessed using electrogustometry (EGM) and the filter paper disc (FPD) method before and up to 1 year after surgery. Questionnaires on taste disturbance, including a visual analogue scale (VAS), and QoL were completed before and up to 1 year after surgery. RESULTS: Subjective taste disturbance anytime during the 1-year follow-up were reported by 62 and 46%, respectively. The difference in EGM 1 week after surgery compared with preoperative EGM was significantly greater among CSOM patients than otosclerosis. One year postoperatively, the difference is non-significant. CONCLUSION: Surgery for CSOM causes greater initial and more long-lasting taste disturbances as compared with surgery for otosclerosis. One-year postoperative taste normalizes for both CSOM and otosclerosis patients according to VAS and EGM measurements. No real change in QoL was seen 1-year postoperatively. LEVEL OF EVIDENCE: Level 2 evidence is prospective observational research with an experimental design.


Subject(s)
Otitis Media/surgery , Otologic Surgical Procedures/adverse effects , Otosclerosis/surgery , Quality of Life , Taste Disorders/etiology , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Postoperative Complications/etiology , Postoperative Period , Prospective Studies , Surveys and Questionnaires , Sweden , Taste/physiology , Visual Analog Scale , Young Adult
7.
8.
J Assoc Res Otolaryngol ; 19(3): 243-260, 2018 06.
Article in English | MEDLINE | ID: mdl-29623476

ABSTRACT

The human tympanic membrane (TM) has a thin outer epidermal layer which plays an important role in TM homeostasis and ear health. The specialised cells of the TM epidermis have a different physiology compared to normal skin epidermal keratinocytes, displaying a dynamic and constitutive migration that maintains a clear TM surface and assists in regeneration. Here, we characterise and compare molecular phenotypes in keratinocyte cultures from TM and normal skin. TM keratinocytes were isolated by enzymatic digestion and cultured in vitro. We compared global mRNA and microRNA expression of the cultured cells with that of human epidermal keratinocyte cultures. Genes with either relatively higher or lower expression were analysed further using the biostatistical tools g:Profiler and Ingenuity Pathway Analysis. Approximately 500 genes were found differentially expressed. Gene ontology enrichment and Ingenuity analyses identified cellular migration and closely related biological processes to be the most significant functions of the genes highly expressed in the TM keratinocytes. The genes of low expression showed a marked difference in homeobox (HOX) genes of clusters A and C, giving the TM keratinocytes a strikingly low HOX gene expression profile. An in vitro scratch wound assay showed a more individualised cell movement in cells from the tympanic membrane than normal epidermal keratinocytes. We identified 10 microRNAs with differential expression, several of which can also be linked to regulation of cell migration and expression of HOX genes. Our data provides clues to understanding the specific physiological properties of TM keratinocytes, including candidate genes for constitutive migration, and may thus help focus further research.


Subject(s)
Keratinocytes/metabolism , MicroRNAs/metabolism , RNA, Messenger/metabolism , Tympanic Membrane/metabolism , Cell Movement/genetics , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Primary Cell Culture , Tympanic Membrane/cytology
9.
Int J Pediatr Otorhinolaryngol ; 107: 140-144, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29501296

ABSTRACT

OBJECTIVE: To evaluate the impact of tympanostomy ventilation tube material (silicone vs fluoroplastic) and shape (short vs long) regarding time to extrusion, occurrence of otorrhea, occlusion, tube removal and occurrence of persistent perforation. METHODS AND MATERIAL: Four different types of ventilation tubes were used; Long Armstrong tubes, Donaldson tubes, Shepard tubes and straight tubes, representing four specific combinations of VT material (silicone or fluoroplastic) and shape (short, double flanged or long, single flanged). Four hundred children scheduled for bilateral tube insertion were included in a randomized trial. The patients received one type of tube in the right ear and another type in the left ear. The incidence of tube extrusion and complications were monitored postoperatively every third month by an otolaryngologist. RESULTS: Twenty-two children were excluded during surgery. Out of the studied 378 children the mean age was 35.3 months. 63.8% were boys. Short tubes extruded earlier than long tubes; hazard ratio (HR) 4.84 (95% CI 3.50-6.69, p < 0.001). Long Armstrong tubes were least prone to extrude. Silicone tubes resulted in significantly longer time to first infection in a VT ear, HR 1.68 (95% CI 1.03-2.76, p = 0.039). Donaldson tubes rendered the longest mean time to first infection (p = 0.025). Infections did not affect tube extrusion rates significantly (p = 0.879). No significant differences were found regarding tube occlusion, tube extraction or persistent perforation. CONCLUSIONS: Long tubes are less prone to extrude early. Long Armstrong tubes have the least propensity to extrude early. Silicone tubes render significantly longer time to first infection. Donaldson tubes result in least infections. Infection does not affect extrusion rates significantly. LEVEL OF EVIDENCE: 1b.


Subject(s)
Middle Ear Ventilation/instrumentation , Otitis Media with Effusion/surgery , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Incidence , Infant , Male , Middle Ear Ventilation/adverse effects , Middle Ear Ventilation/methods , Postoperative Complications/epidemiology
10.
Stem Cells Dev ; 27(10): 649-657, 2018 05 15.
Article in English | MEDLINE | ID: mdl-29571277

ABSTRACT

Epidermal cells with stem cell-like characteristics have been identified in the tympanic membrane (TM) and localized specifically to the umbo and annulus regions. While they have been proposed to play a role in the regeneration of both acute and chronic TM perforations, evidence for the mechanism and regulation of their contribution is not yet described. Indeed, the behavior of these putative stem cells is largely unknown, in part due to a lack of refined methods for efficient cell isolation. In this study, we compared different explant techniques using normal and perforated rat TM tissues and investigated their ex vivo characteristics. TM after perforation in vivo showed increased staining for epidermal stem cell markers integrin ß1 and cytokeratin (CK) 19, and for proliferation Ki-67, indicating activation of the proliferative centers. A mixed population of fibroblasts and epithelial cells were isolated from explant cultures. Excised TM umbo implanted on a culture well insert was the most effective technique. Explants made from perforated TM produced cells before those from unperforated TM. More importantly, the implanted TM umbo organoid was capable of producing cells in a continuous manner, allowing subsequent harvest using trypsin. Primary rat TM epithelial cell cultures positive for pancytokeratin had colony forming activity and could be enriched for CK 19-positive cells that were capable of culture expansion by proliferation and cell migration when subject to a wound assay. Taken together, trauma to the TM activated the proliferative centers and prompted early cell production from TM umbo organoid cultures, which produced TM stem cell-like cultures that proved suitable for tissue engineering of the TM.


Subject(s)
Regeneration/physiology , Stem Cells/cytology , Tympanic Membrane/cytology , Animals , Cell Culture Techniques/methods , Cell Movement/physiology , Cell Proliferation/physiology , Cell Separation/methods , Cells, Cultured , Epithelial Cells/cytology , Fibroblasts/cytology , Fibroblasts/metabolism , Ki-67 Antigen/metabolism , Male , Rats , Rats, Sprague-Dawley , Stem Cells/metabolism , Tissue Engineering/methods , Tympanic Membrane/metabolism , Tympanic Membrane Perforation/metabolism , Wound Healing/physiology
11.
Otol Neurotol ; 39(3): 333-339, 2018 03.
Article in English | MEDLINE | ID: mdl-29342039

ABSTRACT

OBJECTIVE: To compare stapes vibrations in different partial ossicular replacement prosthesis (PORP) applications. METHODS: Stapedial vibrations were measured on fresh frozen human temporal bones with laser Doppler vibrometry. Eight different types of common ossiculoplasty methods were compared regarding recovery of stapes vibrations in relation with the normal ossicular chain. The PORPs were divided into three groups: 1) PORPs with the lateral contact only with the tympanic membrane, 2) PORPs with lateral contact only to the malleus handle, and 3) PORPs with lateral contact with both the malleus handle and the tympanic membrane. RESULTS: The PORPs with lateral contact only to the malleus handle performed better than the PORPs with lateral contact to the tympanic membrane only at 2 kHZ, but the best recovery was found in the group with contact both to the malleus handle and the tympanic membrane. CONCLUSION: The best sound transmission might be achieved by placing a PORP in contact with both the tympanic membrane and the handle of the malleus.


Subject(s)
Malleus/surgery , Ossicular Prosthesis , Otologic Surgical Procedures/methods , Stapes/physiology , Tympanic Membrane/surgery , Humans , Incus/surgery , Models, Biological , Temporal Bone/surgery , Vibration
12.
Hear Res ; 357: 46-53, 2018 01.
Article in English | MEDLINE | ID: mdl-29190487

ABSTRACT

Ossicular fixation through otosclerosis, chronic otitis media and other pathologies, especially tympanosclerosis, are treated by surgery if hearing aids fail as an alternative. However, the best hearing outcome is often based on knowledge of the degree and location of the fixation. Objective methods to quantify the degree and position of the fixation are largely lacking. Laser vibrometry is a known method to detect ossicular fixation but clinical applicability remains limited. A new method, minimally invasive laser vibrometry (MIVIB), is presented to quantify ossicle mobility using laser vibrometry measurement through the ear canal after elevating the tympanic membrane, thus making the method feasible in minimally invasive explorative surgery. A floating mass transducer provides a clinically relevant transducer to drive ossicular vibration. This device was attached to the manubrium and drove vibrations at the same angle as the longitudinal axis of the stapes and was therefore used to assess ossicular chain mobility in a fresh-frozen temporal bone model with and without stapes fixation. The ratio between the umbo and incus long process was shown to be useful in assessing stapes fixation. The incus-to-umbo velocity ratio decreased by 15 dB when comparing the unfixated situation to stapes fixation up to 2.5 kHz. Such quantification of ossicular fixation using the incus-to-umbo velocity ratio would allow quick and objective analysis of ossicular chain fixations which will assist the surgeon in surgical planning and optimize hearing outcomes.


Subject(s)
Diagnostic Techniques, Otological/instrumentation , Ear, Middle/physiology , Lasers , Movement , Stapes/physiology , Transducers, Pressure , Acoustic Stimulation , Equipment Design , Humans , Pressure , Time Factors , Vibration
13.
Int J Pediatr Otorhinolaryngol ; 103: 58-64, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29224767

ABSTRACT

OBJECTIVES: The aim of the study was to evaluate the antibacterial efficacy of Lugol's solution, acetic acid, and boric acid against Staphylococcus aureus biofilm. METHODS: The efficacy of Lugol's solution 1%, 0.1%, and 0.05%, acetic acid 5% or boric acid 4.7% for treatment of Staphylococcus aureus biofilm in vitro was tested using 30 clinical strains. Susceptibility in the planktonic state was assessed by disk diffusion test. Antiseptic effect on bacteria in biofilm was evaluated by using a Biofilm-oriented antiseptic test (BOAT) based on metabolic activity, a biofilm bactericidal test based on culturing of surviving bacteria and confocal laser scanning microscopy combined with LIVE/DEAD staining. RESULTS: In the planktonic state, all tested S. aureus strains were susceptible to Lugol's solution and acetic acid, while 27 out of 30 tested strains were susceptible to boric acid. In biofilm the metabolic activity was significantly reduced following exposure to Lugol's solution and 5% acetic acid, while boric acid exposure led to no significant changes in metabolic activities. In biofilm, biocidal activity was observed for Lugol's solution 1% (30/30), 0.1% (30/30), and 0.05% (26/30). Acetic acid and boric acid showed no bactericidal activity in this test. Confocal laser scanning microscopy, assessed in 4/30 strains, revealed significantly fewer viable biofilm bacteria with Lugol's solution (1% p < 0.001, 0.1% p = 0.001 or 0.05% p = 0.001), acetic acid 5% for 10 min (p = 0.001) or 30 min (p = 0.015), but not for acetic acid for 1 min or boric acid. CONCLUSION: Lugol's solution 1.0% and 0.1% effectively eradicated S. aureus in biofilm and could be an alternative to conventional topical antibiotics where S. aureus biofilm is suspected such as external otitis, pharyngitis and wounds.


Subject(s)
Acetic Acid/pharmacology , Anti-Infective Agents, Local/pharmacology , Biofilms/drug effects , Boric Acids/pharmacology , Iodides/pharmacology , Staphylococcus aureus/drug effects , Microscopy, Confocal
15.
Acta Otolaryngol ; 137(9): 928-934, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28471720

ABSTRACT

HYPOTHESIS: To examine the cellular events following induced superficial lesions of the human tympanic membrane (TM). Such information could lead to enhanced appreciation of repair mechanisms and novel strategies to restore TM perforations. BACKGROUND: Persistent perforation of the TM in chronic otitis media is a major global health problem and frequently necessitates surgical intervention. Most TM perforations heal spontaneously and swiftly, but sometimes healing fails. The underlying mechanisms and the reason for incomplete repair are often elusive, although some mechanisms have been proposed. METHODS: Here, five healthy adult human TMs were sampled during vestibular schwannoma surgery. Three days before harvesting, three TMs were superficially lesioned, including the epithelial and sub-epithelial layers, using a needle and two TMs served as controls. Light and transmission electron microscopy were performed. RESULTS: Surrounding lesion showed distinct ultrastructural changes. This included a keratinocyte frontier with electron-dense cells with abundant ribosomes and nuclei metamorphosis. Beneath, were activated fibroblasts and invaded/transformed free cells and signs of increased transcellular activity of adjacent blood vessels. CONCLUSIONS: The study describes dynamic morphological events of a human lesioned TM. The human model may be used for further investigations and understanding of TM healing mechanisms.


Subject(s)
Tympanic Membrane Perforation/pathology , Tympanic Membrane/injuries , Tympanic Membrane/ultrastructure , Wound Healing , Humans , Microscopy, Electron, Transmission , Tympanic Membrane/physiology
16.
Acta Otolaryngol ; 137(9): 940-944, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28537107

ABSTRACT

INTRODUCTION: Results of fat graft myringoplasty are often reported with only short-term follow-up. Audiological results are less commonly reported, as well as long-term follow-up results. MATERIALS AND METHODS: One hundred consecutive patients scheduled for fat graft myringoplasty were included in a prospective cohort study. Clinical and audiological outcomes were assessed at six weeks and one year postoperatively. RESULTS: Perforation sizes ranged from 0.5 to 4 mm. The six-week follow-up showed a total perforation closure rate of 72.9% with a statistically significant (p = .03) higher rate for the pediatric age group (83.0%). 64.4% of all patients were healed at one-year follow-up. Statistical analyses for background factors did not reveal any significant difference in healing rates with regard to patient sex or location or cause of the perforation. The mean preoperative air-conduction (AC) threshold was 25 dB with an air-bone gap of 12 dB. At the one-year follow-up the mean air conduction threshold for healed ears was improved to 16.6 dB, still 54.2% of them had a type B tympanogram. CONCLUSIONS: Children had a higher perforation closure rate at six-week follow-up than adult patients. Recurrent tympanic membrane perforations were common after initially successful fat graft myringoplasties. Long-term hearing was improved after successful fat graft myringoplasty, resulting in a mean AC threshold of 16.6 dB.


Subject(s)
Adipose Tissue/transplantation , Myringoplasty/methods , Tympanic Membrane Perforation/surgery , Acoustic Impedance Tests , Adolescent , Adult , Aged , Aged, 80 and over , Audiometry , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Male , Middle Aged , Young Adult
17.
Int J Pediatr Otorhinolaryngol ; 93: 88-96, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28109506

ABSTRACT

OBJECTIVE: To evaluate histologically the progressive development and underlying mechanisms of chronic tympanic membrane perforation (TMP) in a rat model using a two-weeks ventilation tube (VT) treatment combined with topical application of mitomycin C/dexamethasone (VT-M/D), compared with normal tympanic membrane and acute TMPs. METHODS: Fifty male Sprague-Dawley rats were divided into three experimental groups: a normal control group (n = 5), an acute TMP group (n = 5) (i.e. 3 days post-myringotomy) and a VT-M/D group (n = 40). The TMs were regularly assessed by otoscopy. The normal control animals were sacrificed on day 0 and the acute TMP group was sacrificed 3 days post-myringotomy for histological and immunohistochemical evaluations. The VT-M/D group was sacrificed at various time points - 14 and 17 days, 3, 4, 6, 8 and 10 weeks. RESULTS: On longitudinal histological examination, compared with normal TM and acute TMP, the perforation edges at the later time points illustrated thickened stratified squamous epithelium rimming around the edges, significant increase in keratin and collagen deposition, increased macrophage infiltration as well as reduced cellular proliferation. Three phases of TMP healing process were identified - the acute healing phase (3-17 days), the transition phase (3-4 weeks) and the chronic phase (6-10 weeks). CONCLUSION: Based on the histological results of this study, the progressive development of chronic TMPs appeared to be associated with increased epidermal thickening, collagen and keratin deposition, macrophage infiltration and reduced cellular proliferation. After the 3-4 weeks of transition phase, the TMPs seemed to have transformed into a non-healing chronic TMP between 6 and 10 weeks.


Subject(s)
Tympanic Membrane Perforation/pathology , Tympanic Membrane/pathology , Wound Healing/physiology , Animals , Biomarkers/metabolism , Cell Proliferation , Chronic Disease , Disease Progression , Epithelium/metabolism , Epithelium/pathology , Epithelium/physiopathology , Macrophages , Male , Rats , Rats, Sprague-Dawley , Tympanic Membrane/metabolism , Tympanic Membrane/physiopathology , Tympanic Membrane Perforation/metabolism , Tympanic Membrane Perforation/physiopathology
18.
Stem Cells Dev ; 26(6): 405-418, 2017 03 15.
Article in English | MEDLINE | ID: mdl-28052725

ABSTRACT

Stem cell therapies for tympanic membrane repair have shown initial experimental success using mesenchymal stem cells in rat models to promote healing; however, the mechanisms providing this benefit are not known. We investigated in vitro the paracrine effects of human adipose-derived stem cells (ADSCs) on wound healing mechanisms for human tympanic membrane-derived keratinocytes (hTM) and immortalized human keratinocytes (HaCaT). ADSC conditioned media (CMADSC) were assessed for paracrine activity on keratinocyte proliferation and migration, with hypoxic conditions for ADSC culture used to generate contrasting effects on cytokine gene expression. Keratinocytes cultured in CMADSC showed a significant increase in cell number compared to serum-free cultures and further significant increases in hypoxic CMADSC. Assessment of ADSC gene expression on a cytokine array showed a range of wound healing cytokines expressed and under stringent hypoxic and serum-free conditions was upregulated (VEGF A, MMP9, Tissue Factor, PAI-1) or downregulated (CXCL5, CCL7, TNF-α). Several of these may contribute to the activity of conditioned media on the keratinocytes with potential applications in TM perforation repair. VEGFA protein was confirmed by immunoassay to be increased in conditioned media. Together with gene regulation associated with hypoxia in ADSCs, this study has provided several strong leads for a stem cell-derived approach to TM wound healing.


Subject(s)
Adipose Tissue/cytology , Keratinocytes/pathology , Paracrine Communication , Stem Cells/cytology , Tympanic Membrane/pathology , Wound Healing , Cell Hypoxia/drug effects , Cell Movement/drug effects , Cell Proliferation/drug effects , Culture Media, Conditioned/pharmacology , Cytokines/metabolism , Gene Expression Profiling , Gene Ontology , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Keratinocytes/drug effects , Paracrine Communication/drug effects
19.
Acta Otolaryngol ; 137(1): 39-43, 2017 Jan.
Article in English | MEDLINE | ID: mdl-27540683

ABSTRACT

CONCLUSION: The incidence of taste disturbance after stapes surgery is high (61.9%), whereas the majority (94.8%) recovers within 1 year. More severe surgical nerve trauma caused more disturbance, implying that the nerve should be handled carefully during surgery. OBJECTIVES: Patients operated on for otosclerosis seem more often to complain about post-operative taste disturbance than those operated on for chronic otitis media, although the chorda tympani nerve more seldom becomes maltreated in stapedotomy. These observations seem paradoxical. It is unclear to what extent a post-operative taste disturbance affects the quality-of-life. This study aims to shed light on the occurrence of post-operative taste disturbances, on possible prognostic factors, and to what extent post-operative taste disturbance impairs the quality-of-life. METHODS: One hundred and thirty-four adults undergoing primary stapedotomy were included. Questionnaires on taste disturbance and quality-of-life (SF-36) were answered before and after surgery, until 1 year post-operatively. RESULTS: Eighty-three (61.9%) study persons reported post-operative taste disturbance. Seven (5.2%) reported persisting disturbance at 1 year. Surgically more traumatized chorda tympani nerves correlated with more severe taste disturbance post-operatively than less traumatized. Taste disturbance at 1 year post-operatively correlate with a decrease of the physical function domain in the SF-36.


Subject(s)
Postoperative Complications/etiology , Stapes Surgery/adverse effects , Taste Disorders/etiology , Adult , Aged , Female , Humans , Male , Middle Aged , Postoperative Complications/psychology , Quality of Life , Taste Disorders/psychology , Young Adult
20.
Int J Pediatr Otorhinolaryngol ; 89: 159-63, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27619049

ABSTRACT

OBJECTIVE: To compare four different types of tympanostomy ventilation tubes (VT); long-shaft and short-shaft silicone tubes and long-shaft and short-shaft fluoroplastic tubes, regarding time to extrusion and events of otorrhea. METHODS: A prospective randomized controlled trial in children with bilateral recurrent acute otitis media or secretory otitis media; four hundred children were randomized to receive one type of VT in the right ear and another type in the left ear. Postoperatively the children were assessed every third month by an otolaryngologist to monitor the incidence of otorrhea and tube extrusion. RESULTS: Out of the 400 children, 22 were excluded during surgery. Mean age was 35.3 months. A majority (63.8%) were boys. Forty-eight children were lost to follow up during the first year. Significantly more short-shaft VTs were extruded after 12 months compared to long-shaft VTs, regardless of material. Significantly higher incidence of otorrhea was found in the fluoroplastic VT ears compared to the silicone ones, regardless of length of tube. CONCLUSION: Long-shaft VTs last longer in the eardrum during the first year of treatment. Silicone tubes render a reduced risk of otorrhea during the first year of treatment.


Subject(s)
Middle Ear Ventilation/instrumentation , Otitis Media with Effusion/surgery , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Male , Middle Ear Ventilation/adverse effects , Middle Ear Ventilation/methods , Postoperative Complications , Prospective Studies , Tympanic Membrane/surgery
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