Allylamine coating on zirconia dental implant surface promotes osteogenic differentiation in vitro and accelerates osseointegration in vivo.

OBJECTIVES: The glow discharge plasma (GDP) procedure has proven efficacy in grafting allylamine onto zirconia dental implant surfaces to enhance osseointegration. This study explored the enhancement of zirconia dental implant properties using GDP at different energy settings (25, 50, 75, 100, and 200 W) both in vitro and in vivo. MATERIALS AND METHODS: In vitro analyses included scanning electron microscopy, wettability assessment, energy-dispersive X-ray spectroscopy, and more. In vivo experiments involved implanting zirconia dental implants into rabbit femurs and later evaluation through impact stability test, micro-CT, and histomorphometric measurements. RESULTS: The results demonstrated that 25 and 50 W GDP allylamine grafting positively impacted MG-63 cell proliferation and increased alkaline phosphatase activity. Gene expression analysis revealed upregulation of OCN, OPG, and COL-I. Both 25 and 50 W GDP allylamine grafting significantly improved zirconia's surface properties (p < .05, p < .01, p < .001). However, only 25 W allylamine grafting with optimal energy settings promoted in vivo osseointegration and new bone formation while preventing bone level loss around the dental implant (p < .05, p < .01, p < .001). CONCLUSIONS: This study presents a promising method for enhancing Zr dental implant surface's bioactivity.

Trismus in head and neck cancer: translation and validation of the Chinese version of the Gothenburg Trismus Questionnaire-2 (C-GTQ-2).

OBJECTIVES: Trismus, marked by restricted mouth opening, significantly affects patients with temporomandibular disorder (TMD) and head and neck cancer (HNC). Despite its prevalence, specialized questionnaires for trismus assessment are scarce. This study aims to fill this gap by translating and validating the Gothenburg Trismus Questionnaire version 2 (GTQ-2) into Chinese (C-GTQ-2), enhancing the evaluation of trismus in HNC and TMD patients. MATERIALS AND METHODS: The study involved 78 HNC patients, 75 TMD patients, and a control group of 150 individuals without trismus symptoms. Participants were asked to complete the C-GTQ-2 and other health-related quality of life (HRQL) instruments. A subset of 30 individuals retook the questionnaire within two weeks to assess test-retest reliability. RESULTS: The C-GTQ-2 demonstrated remarkable reliability, with Cronbach's alpha values exceeding 0.70 in three of the four domains, indicating high internal consistency. The instrument also showcased high intra-class correlations in the test-retest, affirming its reliability. Furthermore, it exhibited strong convergent validity, aligning well with other HRQL instruments, and effectively discriminated between patients with and without trismus, establishing its discriminant validity. CONCLUSIONS: The C-GTQ-2 emerges as a valid and reliable tool for assessing trismus in HNC and TMD patients, promising to significantly enhance both clinical and research approaches to managing trismus-related complications in the Chinese-speaking demographic. CLINICAL RELEVANCE: C-GTQ-2 proves effective for trismus assessment in head and neck cancer and temporomandibular disorder patients, offering enhanced clinical and research utility.

Acceleration of the biodegradation of cationic polyacrylamide by the coupling effect of thermophilic microorganisms and high temperature in hyperthermophilic composting.

As a flocculant of sewage sludge, cationic polyacrylamide (CPAM) enters the environment with sludge and exists for a long time, posing serious threats to the environment. Due to the environmental friendliness and high efficiency in the process of organic solid waste treatment, hyperthermophilic composting (HTC) has received increasing attention. However, it is still unclear whether the HTC process can effectively remove CPAM from sludge. In this study, the effects of HTC and conventional thermophilic composting (CTC) on CPAM in sludge were compared and analyzed. At the end of HTC and CTC, the concentrations of CPAM were 278.96 mg kg-1 and 533.89 mg kg-1, respectively, and the removal rates were 72.17% and 46.61%, respectively. The coupling effect of thermophilic microorganisms and high temperature improved the efficiency of HTC and accelerated the biodegradation of CPAM. The diversity and composition of microbial community changed dramatically during HTC. Geobacillus, Thermobispora, Pseudomonas, Brevundimonas, and Bacillus were the dominant bacteria responsible for the high HTC efficiency. To our knowledge, this is the first study in which CPAM-containing sludge is treated using HTC. The ideal performance and the presence of key microorganisms revealed that HTC is feasible for the treatment of CPAM-containing sludge.

Measuring distance from the incisors to the esophageal cancer by FDG PET/CT: endoscopy as the reference.

BACKGROUND: Using endoscopy as the reference, this study evaluated the accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in measuring distance from the incisors to the PET detectable esophageal cancer. If there is high concordance between endoscopic and PET measurements, our results may provide a basis to use FDG PET/CT in cooperation with endoscopic measurement to localize those PET/CT and CT undetectable esophageal tumors for radiotherapy planning. MATERIALS: Esophageal cancer patients with pretreatment endoscopy and FDG PET/CT detectable esophageal tumors were recruited retrospectively. The distances from the incisors to the proximal esophageal tumor margins were determined by endoscopy and by the sagittal images of FDG PET/CT. The endoscopic measurement was used as the comparative reference. A nuclear medicine doctor and a radiation oncologist each performed the FDG PET/CT measurement twice for every patient. We analyzed the differences in these measurements, and assessed agreement and reproducibility of the results by the intraclass correlation coefficient (ICC). RESULTS: Thirty-four patients, with 35 esophageal tumors, were included. By endoscopy and FDG PET/CT, the mean distances from the incisors to the proximal esophageal tumor margin were 27.3 ± 6.4 cm (range 17.1-40.0 cm) and 26.8 ± 6.3 cm (range 15.7-41.3 cm), respectively. The mean absolute differences between the endoscopic and four FDG PET/CT measurements ranged from 1.129 to 1.289 cm (SD: 0.98-1.19). The measurement agreement between FDG PET/CT and endoscopy by ICC was between 0.962 and 0.971. The intra- and interobserver reproducibilities of the two readers were excellent (intraobserver ICC: 0.985, 0.996; interobserver ICC: 0.976-0.984). CONCLUSIONS: FDG PET/CT was in high agreement with endoscopy in measuring the distance from the incisors to the proximal esophageal tumor margin. For FDG PET/CT and CT undetectable esophageal cancer, incorporation of the endoscopic measurement with PET/CT might be a way for making radiotherapy plan.

Exploring the Risk Factors of Sudden Cardiac Death Using an Electrocardiography and Medical Ultrasonography for the General Population Without a History of Coronary Artery Disease or Left Ventricular Ejection Fraction <35% and Aged >35 Years　- A Novel Point-Based Prediction Model Based on the Chin-Shan Community Cardiovascular Cohort.

BACKGROUND: Most of the factors and prediction models of sudden cardiac death (SCD) have been developed without considering the Asia population. The purpose of this study is to construct a point-based prediction model for the general population in Asia.Methods and Results: Chin-Shan Community Cardiovascular Cohort (CCCC) is a community-based longitudinal cohort initiated between 1990 and 1991, enrolling participants aged ≥35 years and following them up until 2005. Participants with coronary artery disease (CAD) or a left ventricular ejection fraction (LVEF) of 35% were excluded from this study. The Framingham risk score function was used to derive a simple point-based prediction model. Based on bootstrapping, a novel model (CCCC-SCD-Score) was validated. A total of 2,105 participants were analyzed. The incidence rate of SCD was 0.406 per 1,000 person-years. The CCCC-SCD-Score score was calculated using age groups (maximal points=4), left ventricular hypertrophy, hypertension, left ventricular ejection fraction <40%, aortic flow rate >190 cm/s, and carotid plaque scores ≥5 (point=1 for each risk factor). The C-index of the CCCC-SCD-Score in predicting SCD risks was 0.888 (95% confidence interval: 0.807-0.969). CONCLUSIONS: For the general Asian population without a history of CAD or a LVEF <35% and who are aged >35 years, the novel model-based scoring system effectively identifies the risk for SCD using the clinical factors, electrocardiographic and echocardiographic data.

The Treatment Efficiency and Microbiota Analysis of Sapindus mukorossi Seed Oil on the Ligature-Induced Periodontitis Rat Model.

Periodontitis is a common oral disease mainly caused by bacterial infection and inflammation of the gingiva. In the prevention or treatment of periodontitis, anti-bacterial agents are used to inhibit pathogen growth, despite increasing levels of bacterial resistance. Sapindus mukorossi Gaertn (SM) seed oil has proven anti-bacterial and anti-inflammation properties. However, the possibility of using this plant to prevent or treat periodontitis has not been reported previously. The aim of this study was to evaluate the effects of SM oil on experimental periodontitis in rats by using micro-CT and microbiota analysis. The distance between cementoenamel junction (CEJ) and alveolar bone crest (ABC) on the sagittal micro-CT slide showed that total bone loss (TBL) was significantly lower in CEJ-ABC distances between SM oil and SM oil-free groups on Day 14. Histology data also showed less alveolar bone resorption, a result consistent result with micro-CT imaging. The microbiota analyzed at phylum and class levels were compared between the SM oil and SM oil-free groups on Day 7 and Day 14. At the phylum level, Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria were the dominant bacterium. Firmicutes in box plot analysis was significantly less in the SM oil group than in the SM oil-free group on Day 7. At the class level, Bacteroidia, Gammaproteobacteria, Bacilli, Clostridia, and Erysipelotrichia were the dominant bacteria. The bacteria composition proportion of Bacilli, Clostridiay, and Erysipelotrichia could be seen in the SM oil group significantly less than in t SM oil-free group on Day 7. Overall, the present results show that topical application of SM oil can reduce bone resorption and change bacteria composition in the ligature-induced periodontitis model. According to these results, it is reasonable to suggest SM oil as a potential material for preventing oral disease.

Preparation of Calcium Phosphate Compounds on Zirconia Surfaces for Dental Implant Applications.

Titanium is widely used in medical implants despite the release of heavy metal ions over long-term use. Zirconia is very close to the color of teeth; however, its biological inertness hinders bonding with bone tissue. Alkaline treatment and coatings of calcium phosphate can be used to enhance bone regeneration adjacent to dental implants. This study examined the effects of alkaline treatment, calcium phosphate coatings, and sintering, on the physical properties of implant material. Our analysis confirmed that the calcium phosphate species were octacalcium phosphate (OCP). The sintering of calcium phosphate was shown to create B-type HAP, which is highly conducive toward the differentiation of mesenchymal stem cells (MSCs) into osteoblasts for the facilitation of bone integration. Conclusions: This study demonstrated the room-temperature fabrication of dental implants with superhydrophilic surfaces to enhance biocompatibility.

2020 International Consensus on First Aid Science With Treatment Recommendations.

This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life-threatening bleeding through the use of tourniquets, hemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research.

Association between TNF-α G-308A (rs1800629) polymorphism and susceptibility to chronic periodontitis and type 2 diabetes mellitus: A meta-analysis.

BACKGROUND AND OBJECTIVE: Although the association between tumor necrosis factor-α (TNF-α) G-308A (rs1800629) polymorphism and chronic periodontitis (CP), chronic periodontitis with type 2 diabetes mellitus (DP) is assumed, results of this association have been contradictory. The aim of this study was to assess the relationship between rs1800629 polymorphism and CP/DP susceptibility. METHODS: We searched for studies on PubMed, Web of Science, MEDLINE, Chinese National Infrastructure, and WanFang databases. Study selection was performed using specific inclusion and exclusion criteria and fulfilled the PECO (participant, exposure, comparison, and outcome) format. The relationship between rs1800629 polymorphism and CP/DP susceptibility was evaluated by the effect summary odds ratio (OR) and 95% confidence intervals (CIs). Allele, dominant, and recessive genetic models were computed to assess the strength of the association. RESULTS: A total of 25 case-control studies were included in the analysis. In the Asian population, TNF-α rs1800629 polymorphism was found to be significantly associated with CP in the overall analyses and for all genetic contrasts, while no significant risks were found among Caucasian populations for all genetic contrasts. The TNF-α rs1800629 polymorphism was also associated with increased DP risk in Asians under the fixed-effects model, but not in the recessive comparison. CONCLUSION: The meta-analysis suggested that TNF-α rs1800629 polymorphism might affect the risk of CP and DP, particularly in individuals of Asian descent.

Two novel protocols for cleaning residual simethicone and fluid in patient-ready duodenoscopes.

BACKGROUND AND AIM: Approximately 42-95% of working channels have been reported to show the presence of residual fluid despite endoscope reprocessing. The aim of this study was to design two novel protocols for cleaning residual simethicone and demonstrate its efficiency by evaluating the residual fluid and cleanliness in the working channels of patient-ready duodenoscopes. METHODS: The designed protocol for cleaning residual simethicone was implemented in manual cleaning and/or high-level disinfection (HLD). The residual fluid inside the working channels was estimated by visual inspection. Adenosine triphosphate (ATP) values were evaluated to determine cleanliness after manual cleaning. RESULTS: Manual cleaning with novel simethicone cleaning protocol demonstrated a significant decrease in fluid droplets (14.6 ± 29.9 vs 0 ± 0, P < 0.001) and ATP values (157 ± 196 relative light units [RLUs] vs 52 ± 41 RLUs, P = 0.031). HLD with simethicone cleaning protocol, using either enzymatic detergent with effective for cleaning simethicone or cleaning time set in the automatic endoscope reprocessor program for 8 min, demonstrated significant decrease in the number of fluid droplets. Follow-up after the implementation of the simethicone cleaning protocol showed a significant decrease in fluid droplets (37.4 ± 41.0 vs 2.1 ± 5.5, P = 0.003) and ATP values (271 ± 268 RLUs vs 82 ± 136 RLUs, P = 0.021). CONCLUSIONS: Simethicone cleaning protocol is advantageous for significantly decreasing fluid droplets and ATP values within endoscope working channels. After manual cleaning with the simethicone cleaning protocol, in particular, no retained fluid droplet was observed in patient-ready duodenoscopes.

Periodontal disease and risk of mortality and kidney function decline in advanced chronic kidney disease: a nationwide population-based cohort study.

OBJECTIVES: Periodontal disease is prevalent in patients with chronic kidney disease (CKD) and potentially associated with kidney function decline. However, it is uncertain whether periodontal disease affects the risk of mortality and morbidity in patients with advanced CKD. MATERIALS AND METHODS: Taiwan's National Health Insurance Research Database was used to conduct a nationwide population-based cohort study. Propensity score matching procedures were performed to select people with stage 5 CKD and to compare the long-term risk of mortality, end-stage renal disease, and major adverse cardiovascular events (MACE) between people with and without periodontal disease. Multivariable Cox regression analyses were conducted to calculate the adjusted hazard ratio (aHR) with 95% confidence interval (CI) for the outcome of interest. RESULTS: A total of 8119 subjects with stage 5 CKD were initially included. After matching to demographic and clinical covariates, 1254 subjects with 7099 person-years of follow-up were selected for analyses. Periodontal disease was not associated with long-term risks of all-cause mortality (aHR: 0.77, 95% CI: 0.49-1.22), progression to end-stage renal disease (aHR: 0.91, 95% CI: 0.75-1.10), or MACE (aHR: 1.18, 95% CI: 0.91-1.53). These findings were generally consistent across subgroups of age, sex, comorbid diabetes, uses of systemic antibiotic, and different dental procedures. CONCLUSIONS: Periodontal disease is not a predictor for long-term mortality or morbidity in patients with advanced CKD. CLINICAL RELEVANCE: These results provide important evidence to elucidate the relationship between periodontitis and critical clinical outcomes of advanced CKD.

Sequential Application of Calcium Phosphate and ε-Polylysine Show Antibacterial and Dentin Tubule Occluding Effects In Vitro.

In this study, ε-polylysine and calcium phosphate precipitation (CPP) methods were employed to induce antibacterial effects and dentin tubule occlusion. Antibacterial effects of ε-polylysine were evaluated with broth dilution assay against P. gingivalis. CPP solution from MCPM, DCPD, and TTCP was prepared. Four concentrations of ε-polylysine(ε-PL) solutions (0.125%, 0.25%, 0.5%, 1%) were prepared. Dentin discs were prepared from recently extracted human third molars. Dentin discs were incubated with P. gingivalis (ATCC 33277) bacterial suspension (ca. 105 bacteria) containing Brain Heart Infusion medium supplemented with 0.1 g/mL Vitamin K, 0.5 mg/mL hemin, 0.4 g/mL L-cysteine in anaerobic jars (37 °C) for 7 days to allow for biofilm formation. P. g-infected dentin specimens were randomly divided into four groups: CPP + 0.125% ε-PL, CPP + 0.25% ε-PL, CPP + 0.5% ε-PL, CPP + 1% ε-PL. On each dentin specimen, CPP solution was applied followed by polylysine solution with microbrush and immersed in artificial saliva. Precipitate formation, antibacterial effects, and occlusion of dentinal tubules were characterized in vitro over up to 72 h using scanning electron microscopy. ε-PL showed 34.97% to 61.19% growth inhibition levels against P. gingivalis (P. g) after 24 h of incubation. On P. g-infected dentin specimens, DCPD + 0.25% ε-PL, and DCPD + 0.5% ε-PL groups showed complete bacterial inhibition and 78.6% and 98.1% dentin tubule occlusion, respectively (p < 0.001). The longitudinal analysis on fractured dentin samples in DCPD and TTCP groups revealed deeply penetrated hydroxyapatite-like crystal formations in dentinal tubules after 72 h of incubation in artificial saliva.

Acid-Activated Motion Switching of DB24C8 between Two Discrete Platinum(II) Metallacycles.

The precise operation of molecular motion for constructing complicated mechanically interlocked molecules has received considerable attention and is still an energetic field of supramolecular chemistry. Herein, we reported the construction of two tris[2]pseudorotaxanes metallacycles with acid-base controllable molecular motion through self-sorting strategy and host-guest interaction. Firstly, two hexagonal Pt(II) metallacycles M1 and M2 decorated with different host-guest recognition sites have been constructed via coordination-driven self-assembly strategy. The binding of metallacycles M1 and M2 with dibenzo-24-crown-8 (DB24C8) to form tris[2]pseudorotaxanes complexes TPRM1 and TPRM2 have been investigated. Furthermore, by taking advantage of the strong binding affinity between the protonated metallacycle M2 and DB24C8, the addition of trifluoroacetic acid (TFA) as a stimulus successfully induces an acid-activated motion switching of DB24C8 between the discrete metallacycles M1 and M2. This research not only affords a highly efficient way to construct stimuli-responsive smart supramolecular systems but also offers prospects for precisely control multicomponent cooperative motion.

Targeting lipid droplet lysophosphatidylcholine for cisplatin chemotherapy.

This study aims to explore lipidic mechanism towards low-density lipoprotein receptor (LDLR)-mediated platinum chemotherapy resistance. By using the lipid profiling technology, LDLR knockdown was found to increase lysosomal lipids and decrease membranous lipid levels in EOC cells. LDLR knockdown also down-regulated ether-linked phosphatidylethanolamine (PE-O, lysosomes or peroxisomes) and up-regulated lysophosphatidylcholine [LPC, lipid droplet (LD)]. This implies that the manner of using Lands cycle (conversion of lysophospholipids) for LDs might affect cisplatin sensitivity. The bioinformatics analyses illustrated that LDLR-related lipid entry into LD, rather than an endogenous lipid resource (eg Kennedy pathway), controls the EOC prognosis of platinum chemotherapy patients. Moreover, LDLR knockdown increased the number of platinum-DNA adducts and reduced the LD platinum amount. By using a manufactured LPC-liposome-cisplatin (LLC) drug, the number of platinum-DNA adducts increased significantly in LLC-treated insensitive cells. Moreover, the cisplatin content in LDs increased upon LLC treatment. Furthermore, lipid profiles of 22 carcinoma cells with differential cisplatin sensitivity (9 sensitive vs 13 insensitive) were acquired. These profiles revealed low storage lipid levels in insensitive cells. This result recommends that LD lipidome might be a common pathway in multiple cancers for platinum sensitivity in EOC. Finally, LLC suppressed both cisplatin-insensitive human carcinoma cell training and testing sets. Thus, LDLR-platinum insensitivity can be due to a defective Lands cycle that hinders LPC production in LDs. Using lipidome assessment with the newly formulated LLC can be a promising cancer chemotherapy method.

Light triggering goldsomes enable local NO-generation and alleviate pathological vasoconstriction.

While nitric oxide (NO) can remedy vasoconstriction, inhalation of NO may cause systematic toxicity. We report a goldsome, which comprises a hollowed poly(lactic-co-glycolic acid) (PLGA) polymersome with S-nitrosoglutathione (GSNO, a NO donor) molecules and gold nanoparticles (Au NPs) incorporated in its hydrophilic core and hydrophobic membrane, respectively. Photothermal heating caused breakdown of polymersomes and enabled NO generation through reaction between GSNO and Au NPs. Photo-illumination at the zebrafish head led to local NO generation and selective cerebral vasodilation while it had little effects in regions away from the illumination site, and effectively mitigated hypoxia induced cerebral vasoconstriction. We demonstrate a translational potential by showing photo-stimulated NO generation with a clinical intravascular optical catheter. In conclusion, the goldsome, which enables light stimulated local NO generation and can be delivered with clinical intravascular optical catheters, should extend applications of NO therapies while surmounting limitations associated with systemic administration.

Enzymatic degradation of ginkgolic acid by laccase immobilized on novel electrospun nanofiber mat.

BACKGROUND: Ginkgo biloba leaf extract contains many active ingredients that are beneficial for health. However, ginkgolic acid, one of the major components found in G. biloba extract, may cause serious allergic and toxic side effects. The purpose of this study is to immobilize the laccase system on the electrospun nylon fiber mat (NFM) to hydrolyze the ginkgolic acid in G. biloba leaf extract efficiently. RESULTS: Novel electrospinning technology successfully produced high-quality nanoscopic fiber mats made of a mixture of multi-walled carbon nanotube and nylon 6,6. Laccase that was immobilized onto the NFM exhibited much higher efficiency in the catalyzation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) than nylon 6,6 pellets. After being immobilized onto the NFM, the pH and temperature stability of laccase were significantly improved. The NFM-immobilized laccase could maintain more than 50% of its original activity even after 40 days of storage or 10 operational cycles. The kinetic parameters, including rate constant (K), the time (τ50) in which 50% of ginkgolic acid hydrolysis was reached, the time (τcomplete) required to achieve complete ginkgolic acid hydrolysis, Km and Vmax were determined, and were 0.07 ± 0.01 min-1 , 8.97 ± 0.55 min, 45.45 ± 2.79 min, 0.51 ± 0.09 mM and 0.49 ± 0.03 mM min-1 mg-1 , respectively. CONCLUSION: The result successfully demonstrated the strong potential of using novel electrospun nanofiber mats as enzyme immobilization platforms, which could significantly enhance enzyme activity and stability. © 2020 Society of Chemical Industry.

Mouth-opening device as a treatment modality in trismus patients with head and neck cancer and oral submucous fibrosis: a prospective study.

OBJECTIVES: This study investigated the clinical effectiveness of intervention with an open-mouth exercise device designed to facilitate maximal interincisal opening (MIO) and improve quality of life in patients with head and neck (H&N) cancer and oral submucous fibrosis (OSF). MATERIALS AND METHODS: Sixty patients with H&N cancer, OSF, and trismus (MIO < 35 mm) participated in the functional rehabilitation program. An open-mouth exercise device intervention group and conventional group, each consisting of 20 patients, underwent a 12-week training and exercising program and follow-up. For the control group, an additional 20 patients were randomly selected to match the demographic characteristics of the aforementioned two groups. RESULTS: The patients' MIO improvements in the aforementioned three groups were 14.0, 10.5, and 1.3 mm, respectively. CONCLUSION: Results of this study confirm the significant improvement in average mouth-opening range. In addition, according to patient feedback, significant improvements in health-related quality of life and reductions in trismus symptoms occurred in the open-mouth exercise device group. CLINICAL RELEVANCE: This newly designed open-mouth exercise device can facilitate trismus patients with H&N cancer and OSF and improve mouth-opening range and quality of life.

The retrograde transverse cervical artery as a recipient vessel for free tissue transfer in complex head and neck reconstruction with a vessel-depleted neck.

BACKGROUND: Reconstruction in a vessel-depleted neck is challenging. The success rates can be markedly decreased because of unavailability of suitable recipient vessels. In order to obtain a reliable flow, recipient vessels away from the zone of fibrosis, radiation, or infection need to be explored. The aim of this report is to present our experience and clinical outcomes using the retrograde flow coming from the distal transverse cervical artery (TCA) as a source for arterial inflow for complex head and neck reconstruction in patients with a vessel-depleted neck. METHODS: Between July 2010 and June 2016, nine patients with a vessel-depleted neck underwent secondary head and neck reconstruction using the retrograde TCA as recipient vessel for microanastomosis. The mean age was 49.6 years (range, 36 to 68 years). All patients had previous bilateral neck dissections and all, except one, had also received radiotherapy. Indications included neck contracture release (n = 3), oral (n = 1), mandibular (n = 3) and pharyngoesophageal (n = 2) reconstruction necessitating free anterolateral thigh (n = 3) and medial sural artery (n = 1) perforator flaps, fibula (n = 3) and ileocolon (n = 2) flaps respectively. RESULTS: There was 100% flap survival rate with no re-exploration or any partial flap loss. One case of intra-operative arterial vasospasm at the anastomotic suture line was managed intra-operatively with vein graft interposition. There were no other complications or donor site morbidity during the follow-up period. CONCLUSIONS: In a vessel-depleted neck, the reverse flow of the TCA may be a reliable option for complex secondary head and neck reconstruction in selected patients.

Regulation of mammalian transcription by Gdown1 through a novel steric crosstalk revealed by cryo-EM.

In mammals, a distinct RNA polymerase II form, RNAPII(G) contains a novel subunit Gdown1 (encoded by POLR2M), which represses gene activation, only to be reversed by the multisubunit Mediator co-activator. Here, we employed single-particle cryo-electron microscopy (cryo-EM) to disclose the architectures of RNAPII(G), RNAPII and RNAPII in complex with the transcription initiation factor TFIIF, all to ~19 Å. Difference analysis mapped Gdown1 mostly to the RNAPII Rpb5 shelf-Rpb1 jaw, supported by antibody labelling experiments. These structural features correlate with the moderate increase in the efficiency of RNA chain elongation by RNAP II(G). In addition, our updated RNAPII-TFIIF map showed that TFIIF tethers multiple regions surrounding the DNA-binding cleft, in agreement with cross-linking and biochemical mapping. Gdown1's binding sites overlap extensively with those of TFIIF, with Gdown1 sterically excluding TFIIF from RNAPII, herein demonstrated by competition assays using size exclusion chromatography. In summary, our work establishes a structural basis for Gdown1 impeding initiation at promoters, by obstruction of TFIIF, accounting for an additional dependent role of Mediator in activated transcription.

Static magnetic field increases survival rate of dental pulp stem cells during DMSO-free cryopreservation.

Successful and efficient cryopreservation of living cells and organs is a key clinical application of regenerative medicine. Recently, magnetic cryopreservation has been reported for intact tooth banking and cryopreservation of dental tissue. The aim of this study was to assess the cryoprotective effects of static magnetic fields (SMFs) on human dental pulp stem cells (DPSCs) during cryopreservation. Human DPSCs isolated from extracted teeth were frozen with a 0.4-T or 0.8-T SMF and then stored at -196 °C for 24 h. During freezing, the cells were suspended in freezing media containing with 0, 3 or 10% DMSO. After thawing, the changes in survival rate of the DPSCs were determined by flow cytometry. To understand the possible cryoprotective mechanisms of the SMF, the membrane fluidity of SMF-exposed DPSCs was tested. The results showed that when the freezing medium was DMSO-free, the survival rates of the thawed DPSCs increased 2- or 2.5-fold when the cells were exposed to 0.4-T or 0.8-T SMFs, respectively (p < 0.01). In addition, after exposure to the 0.4-T SMF, the fluorescence anisotropy of the DPSCs increased significantly (p < 0.01) in the hydrophilic region. These results show that SMF exposure improved DMSO-free cryopreservation. This phenomenon may be due to the improvement of membrane stability for resisting damage caused by ice crystals during the freezing procedure.