Reduction of methicillin-resistant Staphylococcus aureus biofilm growth and development using arctic berry extracts.

Introduction: Surgical site infection remains a devastating and feared complication of surgery caused mainly by Staphylococcus aureus (S. aureus). More specifically, methicillin-resistant S. aureus (MRSA) infection poses a serious threat to global health. Therefore, developing new antibacterial agents to address drug resistance are urgently needed. Compounds derived from natural berries have shown a strong antimicrobial potential. Methods: This study aimed to evaluate the effect of various extracts from two arctic berries, cloudberry (Rubus chamaemorus) and raspberry (Rubus idaeus), on the development of an MRSA biofilm and as treatment on a mature MRSA biofilm. Furthermore, we evaluated the ability of two cloudberry seed-coat fractions, hydrothermal extract and ethanol extract, and the wet-milled hydrothermal extract of a raspberry press cake to inhibit and treat biofilm development in a wound-like medium. To do so, we used a model strain and two clinical strains isolated from infected patients. Results: All berry extracts prevented biofilm development of the three MRSA strains, except the raspberry press cake hydrothermal extract, which produced a diminished anti-staphylococcal effect. Discussion: The studied arctic berry extracts can be used as a treatment for a mature MRSA biofilm, however some limitations in their use exist.

ALS patients in otorhinolaryngology: A retrospective study.

Objectives: Given its rarity and the lack of clear clinical markers, amyotrophic lateral sclerosis (ALS) remains a diagnostic challenge. Because bulbar-onset ALS (buALS) presents with impaired speech or swallowing, patients are often primarily referred to an otolaryngologist (ORL) or phoniatrician. The objectives of this retrospective cohort study were to analyze the role of ORLs and phoniatricians in ALS diagnostics and treatment and the potential diagnostic delay related to initial visit to aforementioned specialists. Methods: We reviewed data for all 327 patients treated for ALS through the Hospital District of Helsinki and Uusimaa (HUS) between 2010 and 2014, focusing specifically on 110 (34%) patients presenting with bulbar nerve onset (buALS). Their presenting symptoms, referral to specialized care, and delay in referral to a neurology clinic were assessed. Indications and findings from swallowing studies were reviewed as well as the incidence of percutaneous endoscopic gastrostomy (PEG) and tracheostomy. Results: Among the 110 patients with buALS, 64 (58%) were primarily referred to a neurologist, 28 (25%) to an ORL, and five (5%) to a phoniatrician. The most common presenting symptom was dysarthria in 89 patients, (81%), followed by dysphagia in 26 (24%). In most cases, an ORL or phoniatrician suspected a neuromuscular disease; however, in eight (24%) cases, the neurological etiology of symptoms was missed. Overall, 49 (45%) patients underwent a swallowing study and 86 (78%) patients underwent PEG placement. Conclusions: Among buALS patients, 30% initially consulted an ORL or phoniatrician and 45% underwent a swallowing study. Based on our results, swallowing studies rarely lead to immediate PEG placement. An initial visit to other specialists had no impact on diagnostic delays or survival.

Finnish Version of the Eating Assessment Tool (F-EAT-10): A Valid and Reliable Patient-reported Outcome Measure for Dysphagia Evaluation.

Our aim was to validate a Finnish version of the Eating Assessment Tool (F-EAT-10) for clinical use and to test its reliability and validity in a multicenter nationwide study. Normative data were acquired from 180 non-dysphagic participants (median age 57.0 years, 62.2% female). Dysphagia patients (n = 117, median age 69.7 years, 53.0% female) referred to fiberoptic endoscopic evaluation of swallowing (FEES) completed F-EAT-10 before the examination and after 2 weeks. Patients underwent the 100-ml water swallow test (WST) and FEES was evaluated using the following three scales: the Yale Pharyngeal Residue Severity Rating Scale, Penetration-Aspiration Scale, and the Dysphagia Outcome Severity Scale. An operative cohort of 19 patients (median age 75.8 years, 57.9% female) underwent an endoscopic operation on Zenker's diverticulum, tight cricopharyngeal muscle diagnosed in videofluorography, or both. Patients completed the F-EAT-10 preoperatively and 3 months postoperatively. The cut-off score for controls was < 3 (sensitivity 94.0%, specificity 96.1%) suggesting that ≥ 3 is abnormal. Re-questionnaires for test-retest reliability analysis were available from 92 FEES patients and 123 controls. The intraclass correlation coefficient was excellent for the total F-EAT-10 score (0.93, 95% confidence interval 0.91-0.95). Pearson correlation coefficients were strong (p < 0.001) for each of the questions and the total score. Internal consistency as assessed by Cronbach's alpha was excellent (0.95). Some correlations between findings in FEES and 100-ml WST with F-EAT-10 were observed. The change in subjective symptoms of operative patients paralleled the change in F-EAT-10. F-EAT-10 is a reliable, valid, and symptom-specific patient-reported outcome measure for assessing dysphagia among Finnish speakers.

Sanguiin H-6 Fractionated from Cloudberry (Rubus chamaemorus) Seeds Can Prevent the Methicillin-Resistant Staphylococcus aureus Biofilm Development during Wound Infection.

Staphylococcus aureus is the most common cause of surgical site infections and its treatment is challenging due to the emergence of multi-drug resistant strains such as methicillin-resistant S. aureus (MRSA). Natural berry-derived compounds have shown antimicrobial potential, e.g., ellagitannins such as sanguiin H-6 and lambertianin C, the main phenolic compounds in Rubus seeds, have shown antimicrobial activity. The aim of this study was to evaluate the effect of sanguiin H-6 and lambertianin C fractionated from cloudberry seeds, on the MRSA growth, and as treatment of a MRSA biofilm development in different growth media in vitro and in vivo by using a murine wound infection model where sanguiin H-6 and lambertianin C were used to prevent the MRSA infection. Sanguiin H-6 and lambertianin C inhibited the in vitro biofilm development and growth of MRSA. Furthermore, sanguiin H-6 showed significant anti-MRSA effect in the in vivo wound model. Our study shows the possible use of sanguiin H-6 as a preventive measure in surgical sites to avoid postoperative infections, whilst lambertianin C showed no anti-MRSA activity.

Microbiome of the Healthy External Auditory Canal.

OBJECTIVE: To investigate the microbiota of the healthy external auditory canal (EAC) culture-independently and to evaluate the usefulness of the swabbing method in collecting EAC microbiota samples. STUDY DESIGN: Cohort study. PATIENTS: Fifty healthy asymptomatic working-age volunteers. INTERVENTION: Samples were harvested with DNA-free swabs from the volunteers' EACs. MAIN OUTCOME MEASURES: Amplicon sequencing of the 16S rRNA gene was used to characterize the microbial communities in the samples. RESULTS: The swabbing method is feasible for EAC microbiota sample collection. The analyzed 41 samples came from 27 female and 14 male subjects; 4 samples were excluded due to recent antimicrobial treatment and 5 because of low sequence count or suspected contaminant microbes. The four most frequent amplicon sequence variants in the microbiota data were Staphylococcus auricularis, Propionibacterium acnes, Alloiococcus otitis, and Turicella otitidis. Typically, the dominant amplicon sequence variant in a sample was one of the most frequent bacteria, but there were also subjects where the dominant species was not among the most frequent ones. The genus Alloiococcus was least common in females who reported cleaning their ears. Subjects with a high relative abundance of Alloiococcus typically had a low abundance of Staphylococcus, which may be a sign of the two being competing members of the microbial community. CONCLUSIONS: The most common bacteria in the microbiome of the healthy EAC were Staphylococcus auricularis, Propionibacterium acnes, Alloiococcus otitis, and Turicella otitidis. The EAC microbiota seems more diverse and individualized than previously thought. Also, ear cleaning habits seem to alter the EAC microbiome.

Strategies to Prevent Biofilm Infections on Biomaterials: Effect of Novel Naturally-Derived Biofilm Inhibitors on a Competitive Colonization Model of Titanium by Staphylococcus aureus and SaOS-2 Cells.

Biofilm-mediated infection is a major cause of bone prosthesis failure. The lack of molecules able to act in biofilms has driven research aimed at identifying new anti-biofilm agents via chemical screens. However, to be able to accommodate a large number of compounds, the testing conditions of these screenings end up being typically far from the clinical scenario. In this study, we assess the potential applicability of three previously discovered anti-biofilm compounds to be part of implanted medical devices by testing them on in vitro systems that more closely resemble the clinical scenario. To that end, we used a competition model based on the co-culture of SaOS-2 mammalian cells and Staphylococcus aureus (collection and clinical strains) on a titanium surface, as well as titanium pre-conditioned with high serum protein concentration. Additionally, we studied whether these compounds enhance the previously proven protective effect of pre-incubating titanium with SaOS-2 cells. Out of the three, DHA1 was the one with the highest potential, showing a preventive effect on bacterial adherence in all tested conditions, making it the most promising agent for incorporation into bone implants. This study emphasizes and demonstrates the importance of using meaningful experimental models, where potential antimicrobials ought to be tested for the protection of biomaterials in translational applications.

Bacterial biofilm in salivary stones.

PURPOSE: To assess the susceptibility of salivary stones to bacterial biofilm formation, which may be involved in the development of salivary gland infection, and to investigate a relation between microbiological aspects and patient characteristics. METHODS: This prospective study comprises of 54 patients with sialolithiasis attended in Helsinki University Hospital during 2014-2016. A total of 55 salivary stones were removed, and studied for biofilm formation using fluorescence microscopy and sonication. The isolated organisms were quantified and identified using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. RESULTS: Biofilm formation was confirmed on the surface of 39 (70.9%) stones. A total of 96 microorganisms were isolated from 45 salivary stones (81.8%). Two or more organisms were isolated in 33 (73.3%) cases. The main isolates were Streptococcus mitis/oralis (n = 27; 28.1%), followed by Streptococcus anginosus (n = 10; 9.6%), Rothia spp. (n = 8; 8.3%), Streptococcus constellatus (n = 7; 7.3%), and Streptococcus gordonii (n = 6; 6.2%). In all patients showing pre-operative (12 cases) or peri-operative (three cases) drainage of pus, the presence of biofilm was detected in microscopy (p = 0.004). Four patients showed post-operative infection, and in three of them (75.0%), the presence of biofilm was detected. Increased number of pus drainage was found among patients with reflux symptoms or use of proton-pump inhibitors. CONCLUSIONS: Salivary stones are susceptible to bacterial biofilm formation, which could be related with the development and severity of the inflammation and the refractory nature of the disease. Sonication of salivary gland stones could be a useful method for finding the etiology of the chronic infection.

Prevention of Biomaterial Infection by Pre-Operative Incubation with Human Cells.

BACKGROUND: Cells of tissues and biofilm forming bacteria compete for the living space on the surface of an implant. We hypothesized the incubation of the implant (titanium, polydimethylsiloxane, and polystyrene surface) with human cells before implantation as a strategy to prevent bacterial adhesion and biofilm formation. METHODS: After 24 hours of incubation with human osteogenic sarcoma SaOS-2 cells (1 × 105 cells/mL), the materials were incubated for 4.5 hours or two days with Staphylococcus aureus in serial 1:10 dilutions of 108 colony-forming units/mL. The bacterial adherence and biofilm biomass on materials pre-incubated with SaOS-2 cells were compared with our previous results on materials incubated only with bacteria or in simultaneous co-culture of SaOS-2 cells and S. aureus. Fluorescent microscopy and crystal violet stain were used. The number of viable SaOS-2 and bacterial cells present was tested using colorimetric methods (MTT, LDH) and drop plate method, respectively. RESULTS: The pre-treatment with human cells was associated with a reduction of bacterial colonization of the biomaterial at 4.5 hours and 48 hours compared with the non-pre-treated materials. The presence of bacteria decreased the number of viable human cells on all materials. ( Supplementary Fig. 1 ; see online supplementary materials at www.liebertpub.com/sur ). CONCLUSIONS: These results suggest that the pre-operative incubation of prostheses with host cells could prevent infection of biomaterials.

Work-up of globus: assessing the benefits of neck ultrasound and videofluorography.

Globus patients with normal ear, nose, and throat (ENT) status are a diagnostic challenge. The symptom may be long lasting and cause concern about malignancy, leading to possibly unnecessary further investigation. The aim of the study was to assess whether radiological examinations are useful in globus diagnostics, how often patients suffer from persistent globus, and whether globus patients with normal ENT status develop a malignancy during a follow-up. We reviewed medical records of all 76 globus patients referred to Helsinki University Hospital, Department of Otorhinolaryngology-Head and Neck Surgery in 2009. Patient history and findings in physical and radiological examinations were registered. A questionnaire concerning patients' present pharyngeal symptoms was sent 3 and 6 years after their initial visit. Data from the Finnish Cancer Registry revealed whether patients developed malignancies within a 3-year follow-up. Based on medical records, neck ultrasound was performed for 37 (49 %) and videofluorography for 22 patients (29 %), with nonsignificant findings. After a 3- and 6-year follow-up, half patients indicated that they were asymptomatic or had fewer symptoms, whereas the rest had persistent symptoms. The Finnish Cancer Registry data confirmed that globus patients developed no head and neck malignancies during a 3-year follow-up. In the present study, neck ultrasound and videofluorography showed no additional benefit to evaluate the globus etiology in patients whose ENT status was normal. Half the globus patients suffered from persistent symptoms after a 3- and 6-year follow-up, indicating that globus may cause discomfort chronically. However, no patients developed malignancies during a 3-year follow-up.

Competitive colonization of prosthetic surfaces by staphylococcus aureus and human cells.

Implantation of a biomaterial provides an adhesion substratum both to host cell integration and to contaminating bacteria. We studied simultaneous competitive adhesion of Staphylococcus aureus in serial 1:10 dilutions of 108 colony forming units (CFU)/mL and human osteogenic sarcoma (SaOS-2) or primary osteoblast (hOB) cells, both 1x105 cells/mL, to the surfaces of titanium, polydimethylsiloxane and polystyrene. The bacterial adherence and human cell proliferation, cytotoxicity and production of reactive oxygen species (ROS) were studied using fluorometric (fluorescent microscopy and flow cytometry) and colorimetric methods (MTT, LDH and crystal violet). The bacterial cell viability was also evaluated using the drop plate method. The presence of bacteria resulted in reduced adherence of human cells to the surface of the biomaterials, increased production of ROS, and into increased apoptosis. On the other hand, the presence of either type of human cells was associated with a reduction of bacterial colonization of the biomaterial with Staphylococcus aureus. These results suggest that increasing colonization of the biomaterial surface in vitro by one negatively affects colonization by the other. Host cell integration to an implant surface reduces bacterial contamination, which opens novel opportunities for the design of infection-resistant biomaterials in current implantology and future regenerative medicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 62-72, 2017.

Dysphagia and malignancy: A three-year follow-up and survey of National Cancer Registry data.

OBJECTIVES/HYPOTHESIS: Dysphagia may cause concern about malignancy. Symptoms are often unspecific; thus, it is essential to identify those requiring further investigations. STUDY DESIGN: Retrospective study combined with patient survey. METHODS: Case records of the 303 dysphagia patients referred in 2009 to Helsinki University Hospital, Department of Otorhinolaryngology-Head and Neck Surgery were surveyed. Based on clinical data, the main cause of symptoms divided patients into five groups. Alarming signs were food sticking in the throat or in the esophagus, weight loss, and progressive dysphagia symptoms. A questionnaire sent 3 years after the primary visit concerned the present symptoms. To investigate whether dysphagia could have been early symptom of malignancy, we surveyed the Finnish Cancer Registry database until the end of 2012. RESULTS: Most diagnoses remained descriptive: unspecific dysphagia (167, 55%). Five (0.02%) had malignant disease, for all of whom the suspicion of malignancy was evident. Finnish Cancer Registry data indicated that unspecific dysphagia did not develop into malignancy during a 3-year follow-up. Returned questionnaires numbered 154 (62%), of which 30 (19%) were asymptomatic patients; relieved symptoms in 36 (23%), fluctuating or unchanged symptoms in 43 (28%), and worse symptoms in 12 (8%). The remaining patients (33, 21%) had not answered that question or the answer was uninterpretable. CONCLUSION: Further investigations to reveal malignancy seemed unnecessary if alarming clinical signs or findings were lacking. After 3 years, almost half the patients were asymptomatic or had milder symptoms revealing the condition's potential for spontaneous recovery. LEVEL OF EVIDENCE: N/A. Laryngoscope, 126:2073-2078, 2016.

Bacterial adhesion on biomedical surfaces covered by yttria stabilized zirconia.

The aim of this study was to compare the bacterial adhesion of Staphylococcus spp. on Ti-6Al-4V with respect to Ti-6Al-V modified alloys with a set of Cubic yttria stabilized zirconia (YSZ) and Ag-YSZ nanocomposite films. Silver is well known to have a natural biocidal character and its presence in the surface predicted to enhance the antimicrobial properties of biomedical surfaces. Microbial adhesion tests were performed using collection strains and twelve clinical strains of Staphylococcus aureus and Staphylococcus epidermidis. The adherence study was performed using a previously published protocol by Kinnari et al. Both collection strains and clinical isolates have shown lower bacterial adhesion to materials modified with respect to the alloy Ti-6Al-4V and the modification with silver reduced the bacterial adhesion for most of all the strains studied. Moreover the percentage of dead bacteria have been evaluated, demonstrating increased proportion of dead bacteria for the modified surfaces. Nanocrystalline silver dissolves releasing both Ag(+) and Ag(0) whereas other silver sources release only Ag(+). We can conclude that YSZ with nanocrystalline silver coating may lead to diminished postoperative infections and to increased corrosion and scratch resistance of YSZ incorporating alloys Ti-6Al-4V.

The role of biofilm in chronic laryngitis and in head and neck cancer.

PURPOSE OF REVIEW: The importance of bacterial biofilm in the human body, both when associated in chronic infections and as the default mode of microbial growth in the normal flora, has been understood during the last two decades. The word biofilm has recently entered into clinical vocabulary especially in dentistry, and oral hygienists have begun to talk of oral or dental biofilm instead of oral plaque. Biofilm presence has been demonstrated widely in otorhinolaryngology, related to chronic infections of middle ear, paranasal sinuses and lymphoid tissue of adenoids and tonsils and to implanted materials; however, less literature exists considering the implication of biofilm to laryngeal infections or head and neck cancer. The research until now has been mainly descriptive and the mechanisms that lead to biofilm formation are unclear and thus there are limited options for specific treatment of biofilm infection. The focus of this article is to review the recent literature considering the bacterial biofilm in larynx and in head and neck surgery. RECENT FINDINGS: Bacterial biofilm has now also been implicated in chronic laryngitis. Among head and neck cancer patients, biofilm is the main reason for the short life cycle of indwelling devices such as voice prostheses and tracheal tubes. Recently, bacterial biofilm has been related to dysplasia and malignancies both as an aetiological factor and as a source of complications. SUMMARY: It has been shown that microbial biofilm is implicated in the mechanisms leading to chronic recalcitrant infections, implant contamination and even to dysplasia. Biofilm has an important role in finding new preventive measures and treatment of these diseases.

Long-term outcome of endoscopic shortening and stiffening of the vocal folds to raise the pitch.

In this study, we aimed to assess the long-term effects of the mucosal layer plastic surgery of the vocal folds performed on the voices of male-to-female transgenders. This retrospective cohort study enrolled 22 patients who were operated during 2004-2010 by a combined technique of transmucosal anterior suturing and stiffening of the vocal folds through a longitudinal cordotomy incision using CO2 laser. Long-term effects were assessed based on completed questionnaires on four different categories including subjective evaluation of patient's own voice perception and a standardized voice inventory (VHI), as well as an acoustic assessment and videolaryngoscopic examination. Out of the 22 patients contacted, 16 returned the questionnaires, and 13 of them participated in the subsequent acoustic analysis and videolaryngoscopic assessment. Results of the study were as follows: The total VHI score, after the procedure, was 32. F0 increased significantly for both the vowel/a/ and text from 157 to 207 Hz and 139 to 162 Hz, respectively. Perturbation measures did not show a significant change. F0 did not correlate with the VHI score. One patient had symptomatic anterior perforation that needed re-operation. The combination of transmucosal anterior suturing and stiffening of the vocal folds by laser cordectomy results in significant elevation of the F0 in the long term and in acceptable levels of VHI score compared to other reports. In conclusion, the results of the procedures show that it is enough to get the mucosal edges sutured together without the need to suture either the ligaments or the muscle of the vocal folds. The need for revision is minimal with this procedure.

Bacterial biofilm associated with chronic laryngitis.

OBJECTIVE: To determine the incidence of biofilm on the vocal fold epithelium of patients with chronic laryngitis. Bacteria can grow in biofilm protected by a glycoprotein mass. Recent studies have shown the importance of biofilm in chronic otolaryngologic infections. Because chronic laryngitis is often recurrent and occasionally purulent, we hypothesized that it is biofilm related. DESIGN: Prospective, controlled, blinded study. Epithelial biopsy specimens from true vocal folds from patients with chronic laryngitis undergoing diagnostic laryngomicroscopy were prepared for confocal scanning laser microscopy (CSLM) and polymerase chain reaction (PCR) microarray: CSLM images were evaluated for bacterial biofilm morphologic characteristics; PCR with microarray-based diagnostic assay was used to identify the bacterial species involved. Patients with vocal fold polyp served as control cases. SETTING: Tertiary care university hospital. PATIENTS: Eighteen consecutive patients were enrolled in the study. Thirteen of them had chronic laryngitis, and 5 had vocal fold polyps. RESULTS: In 9 cases, the CSLM revealed bacterial growth in biofilm form, and most of these specimens (8 out of 9) were from patients with chronic laryngitis. The PCR results were positive in 13 cases, including all 9 biofilm-positive cases. CONCLUSIONS: Direct detection of biofilm in laryngeal biopsy specimens from patients with chronic laryngitis supports the hypothesis that chronic laryngitis may be biofilm related. Biofilm was found in 62% of the cases of chronic laryngitis. To our knowledge, this is the first report of bacterial biofilm associated with chronic laryngitis; however, further investigation is warranted before a clear conclusion can be drawn.

Mastoid biofilm in chronic otitis media.

HYPOTHESIS: We designed a study to determine the role of mastoid mucosal biofilm in chronic otitis media (COM). BACKGROUND: Biofilm formation has been found in several chronic airway infections. COM is associated with chronic, recalcitrant infection of the mastoid mucosa, and surgery often is required. METHODS: COM patients were divided into 2 groups: one with chronic suppurative otitis media (CSOM) and one with cholesteatoma presence. All COM patients had mastoid involvement in a preoperative computed tomographic scan. The control group consisted of patients undergoing cochlear implantation, with no previous history of chronic otitis media. Mastoid mucosa samples were harvested during mastoidectomy. The samples were studied with multiplex-polymerase chain reaction and with CSLM using BacLight Live/Dead stain. Routine bacterial culture was performed in selected cases. RESULTS: A total of 29 COM patients underwent mastoidectomy. Mastoid mucosal biofilm formation could be found in 19 (66%) of these patients. In the control group, there were 11 cases of cochlear implantation, and 1 patient (9%) presented mastoid mucosal biofilm. In the cholesteatoma group, there were 17 patients, of which, 14 (82%) presented biofilm, whereas in the CSOM group, 5 (42%) of 12 patients presented biofilm. The correlation between COM and biofilm was statistically significant (Fisher's exact test, p = 0.003), as was the correlation between cholesteatoma and biofilm, in comparison with the CSOM group (Fisher's exact test, p = 0.046). CONCLUSION: Mastoid mucosal biofilm could be seen in patients with COM with or without cholesteatoma. The role of mastoid biofilm in the development of cholesteatoma should be studied further.

In vitro adhesion of staphylococci to diamond-like carbon polymer hybrids under dynamic flow conditions.

This study compares the ability of selected materials to inhibit adhesion of two bacterial strains commonly implicated in implant-related infections. These two strains are Staphylococcus aureus (S-15981) and Staphylococcus epidermidis (ATCC 35984). In experiments we tested six different materials, three conventional implant metals: titanium, tantalum and chromium, and three diamond-like carbon (DLC) coatings: DLC, DLC-polydimethylsiloxane hybrid (DLC-PDMS-h) and DLC-polytetrafluoroethylene hybrid (DLC-PTFE-h) coatings. DLC coating represents extremely hard material whereas DLC hybrids represent novel nanocomposite coatings. The two DLC polymer hybrid films were chosen for testing due to their hardness, corrosion resistance and extremely good non-stick (hydrophobic and oleophobic) properties. Bacterial adhesion assay tests were performed under dynamic flow conditions by using parallel plate flow chambers (PPFC). The results show that adhesion of S. aureus to DLC-PTFE-h and to tantalum was significantly (P < 0.05) lower than to DLC-PDMS-h (0.671 ± 0.001 × 10(7)/cm(2) and 0.751 ± 0.002 × 10(7)/cm(2) vs. 1.055 ± 0.002 × 10(7)/cm(2), respectively). No significant differences were detected between other tested materials. Hence DLC-PTFE-h coating showed as low susceptibility to S. aureus adhesion as all the tested conventional implant metals. The adherence of S. epidermidis to biomaterials was not significantly (P < 0.05) different between the materials tested. This suggests that DLC-PTFE-h films could be used as a biomaterial coating without increasing the risk of implant-related infections.

Interactions of human bone cells with diamond-like carbon polymer hybrid coatings.

Diamond-like carbon (DLC) coatings produced using the plasma-accelerating filtered pulsed arc discharge (FPAD) method display excellent adherence to the substrate and improve its corrosion resistance. This article reports the interactions of human osteoblastic cells with DLC and two DLC polymer hybrid (DLC-p-h) coatings deposited on smooth, matt and rough silicon wafers by the FPAD method. The DLC-p-h materials were DLC-polytetrafluoroethylene hybrid (DLC-PTFE-h) and DLC-polydimethylsiloxane hybrid (DLC-PDMS-h) coatings. The biocompatibility of the coatings was assayed by using mesenchymal stem cells, primary osteoblasts and Saos-2 cells. Human mesenchymal stem cells proliferated when cultured on DLC and DLC-PTFE-h, but their numbers diminished on DLC-PDMS-h. In all three cell types studied, phalloidin-TRITC staining disclosed cell-type organization typical of an actin cytoskeleton on DLC and DLC-PTFE-h, but minimal and disorganized stress fibers on cells cultured on DLC-PDMS-h. The microtubular cytoskeleton was similarly disorganized on DLC-PDMS-h. Cells on DLC-PDMS-h developed a peculiar form of membrane damage, with nuclear staining by propidium iodide associated with granular calcein staining of the cytoplasm. Active caspase-3 labeling was only seen in cells cultured on DLC-PDMS-h, indicating that these cells undergo apoptosis induced by defective cell adhesion. Results suggest that DLC-PDMS-h coatings might be useful in orthopedic applications where an implant or implant-facet should be protected against bone overgrowth while DLC and DLC-PTFE-h coatings might improve osseointegration.

Can head position after anesthesia cause occlusion of the tympanostomy tube?

OBJECTIVE: Owing to anecdotal evidence, in bilateral tympanostomy, there is a risk of tube occlusion in the ear that stays superior during the recovery after anesthesia. This observational analysis was designed to evaluate the side difference of tympanostomy tube occlusions owing to head position during the operation and postoperative recovery. It was part of a prospective clinical trial with bilateral tympanostomy tube insertion that was conducted to evaluate the effect of albumin coating tympanostomy tube sequelae. METHODS: In the bilateral tympanostomy, the right ear was always operated on first. After left ear tube insertion and during the recovery phase after anesthesia, the patient was turned to lie on the right side. The number of tube sequelae were studied during a 9-month follow-up period. RESULTS: At the first 1-month follow-up visit, 7 right ear tubes and 18 left ear tubes had occluded (p = .043). The same tendency was seen throughout the follow-up. Also, according to a survival analysis, in which survival functions according to laterality were compared using the log-rank test, stratified by tube coating, the left tube occluded at a significantly higher rate. CONCLUSIONS: The position of the patient's head when awake after anesthesia may have an influence on tube occlusion. In this study, the tube located superiorly was occluded more often. This tendency remained during the follow-up. We concluded that there is a possible association between the position of the head during early recovery and occlusion of the tympanostomy tube.