Resorbable Microspheres versus Trisacryl Gelatin Microspheres for Uterine Artery Embolization: A Randomized Controlled Trial.

Background There are insufficient data comparing resorbable microspheres (RMs) with permanent trisacryl gelatin microspheres (TAGMs) for uterine artery embolization (UAE). Purpose To compare therapeutic efficacy and clinical outcomes in participants with symptomatic fibroids after UAE with RMs or TAGMs. Materials and Methods This randomized controlled trial included participants undergoing UAE for symptomatic fibroids at a single institution (from May 2021 to May 2023). Participants were randomized one-to-one to undergo UAE with either RMs or TAGMs. Numeric rating scale pain scores and cumulative fentanyl consumption were assessed for 24 hours after undergoing UAE. Anti-Mullerian hormone was measured to assess effects of UAE on ovarian function. MRI was performed before and 3 months after UAE to evaluate fibroid necrosis and uterine artery recanalization. Repeated variables such as pain were analyzed using Mann-Whitney U test with post hoc Bonferroni correction. Results Sixty female participants (mean age, 45.7 years ± 3.6 [SD]) completed the study, with 30 in each group. No evidence of a difference in pain scores was observed between groups (P > .99). Moreover, there was no evidence of a difference in the total fentanyl consumption at 24 hours after UAE between groups (median: RMs, 423 [IQR, 330-530] vs TAGMs, 562 [IQR, 437-780]; P = .15). Serum anti-Mullerian hormone 3 months after UAE showed no evidence of a difference between groups (RMs vs TAGMs, 0.71 ng/mL ± 0.73 vs 0.49 ng/mL ± 0.45, respectively; P = .09). No evidence of a difference in the rate of complete necrosis of the dominant fibroid was observed between groups (97% [29 of 30] for both groups; P > .99). The rate of uterine artery recanalization was higher in RM versus TAGM groups (70% [21 of 30] vs 17% [five of 30], respectively; P < .001). Conclusion UAE with RMs, compared with UAE with TAGMs, showed no evidence of a difference in terms of therapeutic effectiveness or postprocedural pain scores in participants with symptomatic fibroids. Clinical trial registration no. NCT05086770 © RSNA, 2024 See also the editorial by Spies in this issue.

Comparison of the Characteristics of Recycled Carbon Fibers/Polymer Composites by Different Recycling Techniques.

In this study, three recycling methods, namely, mechanical grinding, steam pyrolysis, and the supercritical solvent process, which are used to acquire recycled carbon fibers (RCFs), were compared for their application in synthesizing polymer-matrix composites. RCF-reinforced polyethylene (PE) composites were prepared to compare the mechanical properties of the composites generated using the three recycling methods. The PE/RCF composites exhibited 1.5 times higher mechanical strength than the RCF-reinforced PE composites, probably because of the surface oxidation effects during the recycling processes that consequently enhanced interfacial forces between the RCF and the matrix. Further, the steam pyrolysis process showed the highest energy efficiency and can thus be applied on a large production scale in domestic recycled CF markets.

Comparative Outcome Analysis of N-Butyl Cyanoacrylate Embolization of the False Lumen Versus Thoracic Endovascular Aortic Repair in Aortic Dissection.

PURPOSE: To evaluate the feasibility, safety, and effectiveness of N-butyl cyanoacrylate (NBCA) embolization for the treatment of aortic dissection. MATERIALS AND METHODS: In this single-center retrospective study conducted from February 2003 to June 2019, NBCA embolization of an aortic false lumen was attempted in 12 patients (median age, 59 y; range, 41-68 y) and thoracic endovascular aortic repair (TEVAR) was performed in 53 patients (median age, 59 y; range, 37-70 y) for aortic dissection with one or more indications of persisting pain, malperfusion, rupture or impending rupture, maximal aortic diameter ≥ 55 mm, and/or rapid aortic enlargement. The main exclusion criterion for embolization was the presence of fast blood flow in the aortic false lumen on aortography. The efficacy of NBCA embolization and TEVAR was compared by evaluating technical and clinical outcomes, repeat intervention-free survival (RFS), and overall survival (OS). RESULTS: Technical success was achieved in 11 of the 12 patients treated with NBCA embolization (91.7%), and clinical success was achieved in 9 of these 11 (81.8%). No significant difference was found between embolization and TEVAR in clinical success rates (embolization, 81.8%; TEVAR, 84.9%; P = .409) or procedure-related complications (embolization, 1 patient [8.3%]; TEVAR, 4 patients [7.5%]; P = .701). In addition, embolization showed comparable 5-y RFS (embolization, 82.5% ± 9.3; TEVAR, 85.5% ± 4.8; P = .641) and 5-y OS (embolization, 100%; TEVAR, 95.4% ± 3.2; P = .744) rates to TEVAR. CONCLUSIONS: NBCA embolization of the false lumen in aortic dissection seems to be a safe and effective treatment modality for the closure of false lumen in selected patients.

Osteogenesis of 3D-Printed PCL/TCP/bdECM Scaffold Using Adipose-Derived Stem Cells Aggregates; An Experimental Study in the Canine Mandible.

Three-dimensional (3D) printing is perceived as an innovative tool for change in tissue engineering and regenerative medicine based on research outcomes on the development of artificial organs and tissues. With advances in such technology, research is underway into 3D-printed artificial scaffolds for tissue recovery and regeneration. In this study, we fabricated artificial scaffolds by coating bone demineralized and decellularized extracellular matrix (bdECM) onto existing 3D-printed polycaprolactone/tricalcium phosphate (PCL/TCP) to enhance osteoconductivity and osteoinductivity. After injecting adipose-derived stem cells (ADSCs) in an aggregate form found to be effective in previous studies, we examined the effects of the scaffold on ossification during mandibular reconstruction in beagle dogs. Ten beagles were divided into two groups: group A (PCL/TCP/bdECM + ADSC injection; n = 5) and group B (PCL/TCP/bdECM; n = 5). The results were analyzed four and eight weeks after intervention. Computed tomography (CT) findings showed that group A had more diffuse osteoblast tissue than group B. Evidence of infection or immune rejection was not detected following histological examination. Goldner trichrome (G/T) staining revealed rich ossification in scaffold pores. ColI, Osteocalcin, and Runx2 gene expressions were determined using real-time polymerase chain reaction. Group A showed greater expression of these genes. Through Western blotting, group A showed a greater expression of genes that encode ColI, Osteocalcin, and Runx2 proteins. In conclusion, intervention group A, in which the beagles received the additional ADSC injection together with the 3D-printed PCL/TCP coated with bdECM, showed improved mandibular ossification in and around the pores of the scaffold.

Risk factors for residual mouth breathing in children who had completely resolved obstructive sleep apnea after adenotonsillectomy.

PURPOSE: Adenotonsillectomy is the first-line treatment for pediatric obstructive sleep apnea (OSA). However, although completely resolved OSA after adenotonsillectomy, some children still showed persistence of mouth breathing. Therefore, we attempted to identify risk factors for residual mouth breathing in children with OSA after successful adenotonsillectomy. MATERIALS AND METHODS: This study retrospectively enrolled children who underwent adenotonsillectomy as a treatment of OSA. Additionally, children who showed apnea-hypopnea index ≥ 1 on 1-year postoperative polysomnography or adenoid regrowth on one-year postoperative lateral cephalogram were excluded. The presence of allergic rhinitis, septal deviation, dentofacial abnormalities, the size of tonsil and adenoid was also evaluated in all enrolled children. Dentofacial abnormalities were defied as a high palatal arch, macroglossia, retrognathia, micrognathia, and overcrowding of teeth which assessed by dentists. RESULTS: A total of 62 children were enrolled (no residual mouth-breathing group, n = 18 and residual mouth-breathing group, n = 44) in this study. There were no significant differences in demographic factors, physical examination, and sleep parameters, except age and preoperative adenoid size. On the multiple logistic regression analysis, we found that older age, large adenoid size, and presence of dentofacial abnormalities significantly correlated with residual mouth breathing (adjusted coefficient estimates = 0.3890, 2.3611, and 2.8615, respectively) after successful adenotonsillectomy. CONCLUSIONS: Older age, large adenoid size, and presence of dentofacial abnormalities in children with OSA may be the risk factors for residual mouth breathing after successfully resolved OSA.

Effect of long-term oral appliance therapy on obstruction pattern in patients with obstructive sleep apnea.

PURPOSE: Oral appliance therapy is an alternative treatment modality for obstructive sleep apnea (OSA). However, there have been no studies to determine whether changes in the obstructive pattern occur following long-term use of oral devices. Therefore, we examined whether the obstructive pattern changes in patients with OSA who undergo long-term oral appliance therapy using drug-induced sleep endoscopy (DISE). METHODS: We investigated 156 consecutive patients diagnosed with OSA. Seventy-nine of these patients were found to be eligible for inclusion in this study. All enrolled patients underwent two DISE examinations: before and after oral appliance use. We compared the DISE findings for each patient in terms of degree and configuration of airway obstruction at the levels of the velum, oropharynx, tongue base, and epiglottis. RESULTS: We found that dental problems, as assessed using the average values of overjet and overbite, were significantly decreased after 2 years of oral appliance use. Comparisons of the DISE findings revealed that there was significant widening of the upper airway structures following long-term oral appliance therapy, especially in the velum (P = 0.022) and epiglottis (P = 0.001). However, changes in the configuration of upper airway obstruction were not observed in any of the structures of the upper airway. CONCLUSIONS: We found evidence possibly indicating decreased obstruction at the levels of the velum and epiglottis after long-term use of oral appliances. We suggest further cohort studies to confirm these findings.

Adenotonsillar hypertrophy as a risk factor of dentofacial abnormality in Korean children.

No studies for the role of adenotonsillar hypertrophy in development of dentofacial abnormalities have been performed in Asian pediatric population. Thus, we aimed to investigate the relationship between adenotonsillar hypertrophy and dentofacial abnormalities in Korean children. The present study included consecutive children who visited a pediatric clinic for sleep-disordered breathing due to habitual mouth breathing, snoring or sleep apnea. Their palatine tonsils and adenoids were graded by oropharyngeal endoscopy and lateral cephalometry. Anterior open bite, posterior crossbite, and Angle's class malocclusions were evaluated for dentofacial abnormality. The receiver-operating characteristic curve analysis was used to identify age cutoffs to predict dentofacial abnormality. A total of 1,083 children were included. The presence of adenotonsillar hypertrophy was significantly correlated with the prevalence of dentofacial abnormality [adjusted odds ratio = 4.587, 95% CI (2.747-7.658)] after adjusting age, sex, body mass index, allergy, and Korean version of obstructive sleep apnea-18 score. The cutoff age associated with dentofacial abnormality was 5.5 years (sensitivity = 75.5%, specificity = 67%) in the children with adenotonsillar hypertrophy and 6.5 years (sensitivity = 70.6%, specificity = 57%) in those without adenotonsillar hypertrophy. In conclusion, adenotonsillar hypertrophy may be a risk factor for dentofacial abnormalities in Korean children and early surgical intervention could be considered with regards to dentofacial abnormality.

Clinical efficacy study of position-responding mandibular advancement device in patients with obstructive sleep apnea.

Objectives: Although mandibular advancement device (MAD) treatment is effective in patients with obstructive sleep apnea (OSA), there are still some concerns about its potential therapeutic and side effects. Thus, we developed a novel MAD that auto-titrates depending on its position in patients with OSA. Therefore, we conducted a clinical trial to determine the efficacy of an auto-titrating mandibular advancement device (AMAD) for treating OSA. Methods: Fourteen patients with OSA were enrolled in this study. Polysomnography (PSG) was conducted at the start of the clinical trial, and PSG with AMAD in situ was performed after three months of treatment. Results: The mean Epworth Sleepiness Scale (ESS) and STOP-Bang scores were 8.21 ± 4.21 and 5.00 ± 1.00, respectively. After 3 months of treating AMAD, STOP-Bang scores improved to 3.75 ± 1.06; however, there was no significant change in ESS scores. Additionally, we found statistically significant improvements in several respiratory parameters in the PSG data after AMAD treatment. The AHI (32.85 ± 21.71 to 12.93 ± 10.70), supine AHI (45.91 ± 23.58 to 15.59 ± 12.76), lateral AHI (13.94 ± 10.95 to .49 ± 7.40), lowest O2 saturation (79.71 ± 6.22 to 84.00 ± 5.71), total arousal number (191.14 ± 112.07 to 86.57 ± 48.80), and arousal index (33.76 ± 21.00 to 15.05 ± 8.42) were recorded. However, there were no significant changes in total sleep time, sleep efficiency, or mean oxygen saturation. Additionally, we did not observe any major side effects during treatment, specifically related to tooth or jaw pain. Conclusion: Our clinical trial revealed that AMAD improved PSG parameters and reduced the incidence of common side effects. Therefore, AMAD may be an effective alternative treatment for OSA.

Dexamethasone acetate loaded poly(ε-caprolactone) nanofibers for rat corneal chemical burn treatment.

Topical eye drop approaches to treat ocular inflammation in dry eyes often face limitations such as low efficiency and short duration of drug delivery. Nanofibers serve to overcome the limitation of the short duration of action of topical eye drops used against ocular inflammation in dry eyes. Several attempts to develop suitable nanofibers have been made; however, there is no ideal solution. Here, we developed polycaprolactone (PCL) nanofibers loaded with dexamethasone acetate (DEX), prepared by electrospinning, as a potential ocular drug delivery platform for corneal injury treatment. Thirty-nine Sprague Dawley rats (7 weeks old males) were divided into four treatment groups after alkaline burns of the cornea; negative control (no treatment group); dexamethasone eyedrops (DEX group); PCL fiber (PCL group); dexamethasone loaded PCL (PCL + DEX group). We evaluated therapeutic efficacy of PCL + DEX by examining the epithelial wound healing effect, the extent of corneal opacity and neovascularization. Additionally, various inflammatory factors, including IL-1ß, were investigated through immunochemistry, western blot analysis, and quantitative real-time RT-PCR (qRT-PCR). PCL + DEX group showed histologically alleviated signs of corneal inflammation compared with DEX group, which showed a decrease in IL-1ß and MMP9 in the corneal stroma. The quantitative expression on day 1 after alkaline burn of pro-inflammatory markers, including IL-1ß and IL-6, in the PCL + DEX group was significantly lower than that in the DEX group. Notably, PCL + DEX treatment significantly suppressed neovascularization, and enhanced the anti-inflammatory function of DEX during the acute phase of ocular inflammation. Collectively, these findings suggest that PCL + DEX may be a promising approach to effective drug delivery in corneal burn injuries.

Relationship of Depression, Anxiety, and Bipolar Disease with Burning Mouth Syndrome: A Nationwide Cohort Study.

Burning mouth syndrome (BMS) is a chronic, painful condition of the oral mucosa. Although the pathogenesis remains unclear, psychological and neuroendocrine factors are considered the major contributors. Few longitudinal studies have investigated the effects of psychological factors on the occurrence of BMS. Therefore, we evaluated the risk of BMS in patients with affective disorders using a nationwide population-based cohort dataset. We identified patients with depression, anxiety, and bipolar disorder and then selected comparison participants using the 1:4 propensity score-matching method. We investigated the incidence of BMS events during the follow-up period using survival analysis, the log-rank test, and Cox proportional hazards regression models. After adjusting for other contributing conditions, the adjusted hazard ratio (HR) for developing BMS was 3.37 (95% confidence interval [CI]: 1.67-6.80) for depression and 5.09 (95% CI: 2.19-11.80) for anxiety; however, bipolar disorder showed no significant risk. Specifically, female patients with depression and anxiety had an increased risk of BMS. Moreover, patients with anxiety showed an increased adjusted HR of BMS events during the first 4 years after diagnosis, whereas patients with depression did not. In conclusion, depression and anxiety disorders are significantly associated with the risk of BMS. Additionally, female patients showed a significantly higher risk of BMS than male patients, and anxiety showed increased BMS events earlier than depression. Therefore, clinicians should consider the risk of BMS when treating patients with depression or anxiety.

Risk of Burning Mouth Syndrome in Patients with Migraine: A Nationwide Cohort Study.

Migraine is a common neurological disease that causes a variety of symptoms, most notably throbbing, which is described as a pulsing headache on one side of the head. Burning mouth syndrome (BMS) is defined as an intra-oral burning sensation. Currently, no medical or dental cause has been identified for BMS. Interestingly, neuropathic pain is a characteristic feature of BMS; however, it remains unclear whether migraine can cause BMS. We aimed to identify the association of migraine with the risk of developing BMS. We used a representative nationwide cohort sample of approximately 1 million patients from 2002 to 2013 to investigate the prospective association between migraine and BMS. A total of 4157 migraine patients (migraine group) and 16,628 patients without migraine (comparison group) were enrolled after 1:4 propensity score matching. The overall incidence of BMS was significantly higher in the migraine group (0.15 per 1000 person-years) than in the comparison group (0.05 per 1000 person-years). The adjusted HR for patients with migraine who reported BMS events during the 10-year follow-up period was 2.96 (95% confidence interval, 1.02-8.56), after adjusting for other covariates. However, in the subgroup analysis, the adjusted HR for BMS events did not show a significant difference between the migraine and comparison group according to sex, age, and comorbidities. This study suggests that migraine is associated with an increased incidence of BMS. Therefore, clinicians should be attentive to detect BMS at an early stage when treating patients with migraine.

Association Between Burning Mouth Syndrome and the Development of Depression, Anxiety, Dementia, and Parkinson Disease.

Importance: Burning mouth syndrome is a chronic oral pain disorder that is characterized by a generalized or localized burning sensation without the presence of any specific mucosal lesions. It remains unclear, however, whether burning mouth syndrome is associated with the development of psychoneurological conditions among patients with the syndrome. Objective: To evaluate the risk of developing psychoneurological conditions, including depression, anxiety, dementia, and Parkinson disease, in patients with burning mouth syndrome. Design, Setting, and Participants: This retrospective population-based cohort study was conducted using a nationwide representative cohort sample from the Korean National Health Insurance Service-National Sample Cohort, which consists of data from approximately 1 million patients in South Korea. The study included 586 patients with burning mouth syndrome (patient group) and 1172 individuals without burning mouth syndrome (comparison group). The patient group included all patients who received inpatient and outpatient care for an initial diagnosis of burning mouth syndrome between January 1, 2002, and December 31, 2012. The comparison group was selected (2 individuals without burning mouth syndrome for each patient with burning mouth syndrome) using propensity score matching for sex, age, location of residence, household income level, and comorbidities. Data were collected and analyzed from January 1, 2002, to December 31, 2013. Main Outcomes and Measures: Death and the incidence of psychopathological diseases. Affective disorder events that occurred among participants during the follow-up period were investigated using survival analysis, a log-rank test, and Cox proportional hazards regression models to estimate the incidence rates, survival rates, and hazard ratios, respectively, of participants who developed psychoneurological conditions. Results: Of 1758 total participants, 1086 (61.8%) were female; 701 participants (39.9%) were younger than 45 years, 667 (37.9%) were aged 45 to 64 years, and 390 (22.2%) were older than 64 years. The overall incidence of depression and anxiety was higher in patients with burning mouth syndrome (n = 586; 30.8 incidents and 44.2 incidents per 1000 person-years, respectively) than in individuals without burning mouth syndrome (n = 1172; 11.7 incidents and 19.0 incidents per 1000 person-years, respectively). The results also indicated a similar incidence of dementia and Parkinson disease between the patient group (6.5 incidents and 2.5 incidents per 1000 person-years, respectively) and the comparison group (4.9 incidents and 1.7 incidents per 1000 person-years, respectively). After adjusting for sociodemographic factors (age, location of residence, household income level, and comorbidities), the adjusted hazard ratios for the development of depression and anxiety among patients with burning mouth syndrome were 2.77 (95% CI, 2.22-3.45) and 2.42 (95% CI, 2.02-2.90), respectively. However, no association was found between burning mouth syndrome and the risk of developing dementia and Parkinson disease. Conclusions and Relevance: Results of this observational study suggest that burning mouth syndrome is associated with increases in the incidence of depression and anxiety but not in the incidence of dementia and Parkinson disease among patients with the syndrome. Clinicians should be aware of this association and be prepared to make referrals to appropriate mental health care professionals.

Pepsin detection in the sputum/saliva for the diagnosis of gastroesophageal reflux disease in patients with clinically suspected atypical gastroesophageal reflux disease symptoms.

BACKGROUND/AIMS: Atypical manifestations of gastroesophageal reflux disease (GERD) are diverse. We aimed to determine whether pepsin detection in the sputum/saliva could be useful for diagnosing GERD in patients with clinically suspected atypical GERD symptoms. METHODS: Patients with clinically suspected atypical GERD symptoms provided sputum/saliva collected before bedtime, at the time of those symptoms, and after awakening for pepsin measurement by Western blot analysis. All subjects received 24-hour esophageal pH monitoring, and then 40 mg of esomeprazole was given twice a day for 2 weeks. RESULTS: The pepsin test was positive in 20 out of 40 patients, with pepsin detected mainly in the samples collected at the time of symptoms (45%). Samples collected from healthy volunteers (n = 8) were all negative for pepsin. 24-hour pH-metry was positive in 9 patients (23%). Based on 24-hour pH-metry data, the sensitivity and negative predictive value of the pepsin test were excellent in most of typical and atypical symptom groups, whereas its specificity and positive predictive value were relatively low, particularly in atypical symptom groups. CONCLUSIONS: Pepsin measurement in the sputum/saliva collected at the time of symptoms provides a sensitive, non-invasive method for diagnosing GERD in patients with clinically suspected atypical GERD symptoms.

New fabrication method of silk fibroin plate and screw based on a centrifugal casting technique.

Recently, a newer generation of absorbable biomaterials has been developed from silk. Silk is approved by the US Food and Drug Administration, has robust mechanical features, and is biocompatible. Moreover, it offers the ability to be functionalized with bioactive compounds, making it ideal for use in new medical devices. Thus, many researchers have considered that absorbable devices made from silk may be able to overcome current limitations and could be used to meet a broader range of fixation needs. Here, we describe a novel method for the fabrication of silk fibroin (SF)-based bioabsorbable fixation systems using a centrifugal casting technique and incorporating a 3D printer. This approach allows us to create the desired geometric design for the fixation system easily. Moreover, our products demonstrated smoother surface profiles and more homogenous and dense cross-sectional architectures. Furthermore, our plates exhibited very similar mechanical properties compared with commercially used one, and our screws showed more than 70% of their initial mass after 7 weeks on the enzymatic degradation test. On in vivo analysis, we found that our devices were well-maintained in the location of initial fixation, and new bone formation was also observed around this. By these results, we suggest that the SF-based plate/screw prepared by our novel method might be used for the internal fixation of fracture sites.

Interleukin-4 receptor-targeted delivery of Bcl-xL siRNA sensitizes tumors to chemotherapy and inhibits tumor growth.

IL-4 receptor (IL-4R) is commonly up-regulated on tumor cells, and interactions between the receptor and Interleukin-4 (IL-4) can induce the expression of anti-apoptotic proteins, including Bcl-xL. This contributes to tumor cell survival and their resistance to chemotherapy. In this study, we exploited IL-4R-targeted delivery of Bcl-xL siRNA to IL-4R-expressing tumor cells in order to sensitize them to chemotherapy. To target IL-4R, an IL-4R-binding peptide, IL4RPep-1, was attached to branched polyethyleneimine-superparamagnetic iron oxide nanoparticles (BPEI-SPION). These nanoparticles were then complexed with Bcl-xL-targeting siRNA. IL-4R-targeted BPEI-SPION/Bcl-xL siRNA more efficiently reduced Bcl-xL gene expression and enhanced cytotoxicity of doxorubicin in MDA-MB231 breast tumor cells compared to untargeted BPEI-SPION/Bcl-xL siRNA. The siRNA was released from the complexes after 15 h of incubation at pH 5.5 and was stable in the complexes up to 72 h in the serum. The IL-4R-targeted BPEI-SPION/siRNA was internalized by cells through IL-4R, successfully escaped the endosomes, and was dispersed into the cytoplasm. Near-infrared fluorescence and magnetic resonance imaging demonstrated that in vivo tumor homing and accumulation of IL-4R-targeted BPEI-SPION/siRNA were both higher than untargeted BPEI-SPION/siRNA. The IL-4R-targeted BPEI-SPION/Bcl-xL siRNA, in combination with doxorubicin, significantly inhibited tumor growth in mice compared to untargeted BPEI-SPION/Bcl-xL siRNA. These results suggest that the IL-4R-targeted delivery of Bcl-xL siRNA to IL-4R-expressing tumors can sensitize tumors to chemotherapy and enhance the efficacy of anti-tumor therapeutics.

Osteoinductive silk fibroin/titanium dioxide/hydroxyapatite hybrid scaffold for bone tissue engineering.

The present study demonstrated the fabrication that incorporation of titanium isopropoxide (TiO2) and hydroxyapatite (HA) nanoparticles into the silk fibroin (SF) scaffolds. In this process, we prepared TiO2 nanoparticles using sol-gel synthesis and the porous structure was developed by salt-leaching process. Homogeneous distribution of TiO2 and HA nanoparticles were confirmed by images of VP-FE-SEM and those equipped with energy dispersive X-ray spectrometer. Structural characteristics of the porous SF/TiO2/HA hybrid scaffold were also determined using FTIR analysis and X-ray diffractometer. In this study, the porous SF/TiO2/HA hybrid scaffold showed similar porosity, enhanced mechanical property, but decreased water binding abilities, compared with the porous SF scaffold. For evaluation of the osteogenic differentiation of rat bone marrow mesenchymal stem cells, alkaline phosphatase activity and osteogenic gene expression were employed. Our results revealed that the porous SF/TiO2/HA hybrid scaffold had improved osteoinductivity compared with the porous SF scaffold. These results suggest that the osteogenic property as well as mechanical property of the porous SF/TiO2/HA hybrid scaffold could be better than the porous SF scaffold. Therefore, the porous SF/TiO2/HA hybrid scaffold may be a good promising biomaterial for bone tissue engineering application.

Hybrid scaffolds based on PLGA and silk for bone tissue engineering.

Porous silk scaffolds, which are considered to be natural polymers, cannot be used alone because they have a long degradation rate, which makes it difficult for them to be replaced by the surrounding tissue. Scaffolds composed of synthetic polymers, such as PLGA, have a short degradation rate, lack hydrophilicity and their release of toxic by-products makes them difficult to use. The present investigations aimed to study hybrid scaffolds fabricated from PLGA, silk and hydroxyapatite nanoparticles (Hap NPs) for optimized bone tissue engineering. The results from variable-pressure field emission scanning electron microscopy (VP-FE-SEM), equipped with EDS, confirmed that the fabricated scaffolds had a porous architecture, and the location of each component present in the scaffolds was examined. Contact angle measurements confirmed that the introduction of silk and HAp NPs helped to change the hydrophobic nature of PLGA to hydrophilic, which is the main constraint for PLGA used as a biomaterial. Thermo-gravimetric analysis (TGA) and FT-IR spectroscopy confirmed thermal decomposition and different vibrations caused in functional groups of compounds used to fabricate the scaffolds, which reflected improvement in their mechanical properties. After culturing osteoblasts for 1, 7 and 14 days in the presence of scaffolds, their viability was checked by MTT assay. The fluorescent microscopy results revealed that the introduction of silk and HAp NPs had a favourable impact on the infiltration of osteoblasts. In vivo experiments were conducted by implanting scaffolds in rat calvariae for 4 weeks. Histological examinations and micro-CT scans from these experiments revealed beneficial attributes offered by silk fibroin and HAp NPs to PLGA-based scaffolds for bone induction.

Antibacterial effects of the povidone-iodine vacuum impregnation technique in expanded polytetrafluoroethylene augmentation rhinoplasty.

Expanded polytetrafluoroethylene (e-PTFE) is a popular graft material for augmentation rhinoplasty. Gore-Tex and Surgiform are two types of e-PTFE; Surgiform has thicker fibrils and is more compact than Gore-Tex. We conducted an ex vivo study to evaluate the ability of povidone-iodine (PVP-I) vacuum pretreatment to prevent infection with these two types of e-PTFE. Gore-Tex and Surgiform specimens were cut into 2-mm(3) pieces, which were separated into two groups. One group for each e-PTFE was disinfected with vacuum PVP-I impregnation and the other group was not disinfected. Using the pieces of implant material, swabs were obtained from the nasal cavities of 20 healthy adults, and the specimens were incubated on agar plates and viewed by scanning electron microscopy (SEM). We found that PVP-I treatment significantly reduced the bacterial colony counts in both the Gore-Tex and Surgiform groups. In the SEM images, bacterial colonies were observed both inside and outside the untreated Gore-Tex; on the untreated Surgiform, they were found primarily on the surface. Few bacteria were detected in the PVP-I-treated Gore-Tex and Surgiform groups. Our findings suggest that PVP-I pretreatment can reduce the risk of infection associated with e-PTFE.