Moderate- to long-term therapeutic outcomes of treated aggressive periodontitis patients without regular supportive care.

BACKGROUND AND OBJECTIVE: Risk for deterioration in treated aggressive periodontitis (AgP) individuals remained unclear. This retrospective cohort study investigated 7-26 years of periodontal outcomes and oral health-related quality of life (OHRQoL) of young adults with advanced periodontitis. MATERIAL AND METHODS: Eighty-nine previously treated patients with AgP were re-examined. Clinical and radiographic parameters before treatment discontinuation and at re-examination were compared. OHRQoL at re-call was assessed with the short-form Oral Health Impact Profile (OHIP-14S). RESULTS: None of the subjects adhered to suggested periodontal therapy and maintenance after discharge. Mean percentage of sites with probing pocket depth (PPD) ≥6 mm at re-examination was 4.5 ± 5.9%. A total of 182 teeth had been lost over time. Tooth loss rate was 0.14/patient/year. From 68 subjects with documented favorable treatment outcomes, higher percentage of sites with PPD ≥6 mm at re-examination and higher radiographic proximal bone loss was associated with current smoking status. Patients with AgP with <20 teeth at re-call had worse OHRQoL than those with ≥20 teeth. Patients with higher full-mouth mean PPD also reported poorer OHRQoL. CONCLUSION: Treatment in patients with AgP who smoke and neglect proper supportive care, risk periodontal disease progression. Substantial tooth loss and higher full-mouth mean PPD led to poorer OHRQoL in this cohort.

Clinical use of venoarterial extracorporeal membrane oxygenation.

With advances in mechanical circulation, venoarterial extracorporeal membrane oxygenation has become an established technique to provide cardiopulmonary support for patients with cardiovascular collapse. This article reviews the physiological principles of such extracorporeal technique and its interaction with the native heart. Practical aspects including equipment, patient selection, and common complications with their prevention and specific management are summarised. The strategy for weaning from venoarterial extracorporeal membrane oxygenation is also discussed.

Clinical use of venovenous extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation has been used clinically for more than 40 years. The technique provides respiratory and/or circulatory support via venovenous and veno-arterial configurations, respectively. We review the basic physiological principles of extracorporeal membrane oxygenation systems in venovenous extracorporeal membrane oxygenation. Clinical aspects including patient selection, equipment, setup, and specific patient management are outlined. Pros and cons of the use of extracorporeal membrane oxygenation in respiratory failure are discussed.

Biochemical characterization of the cell-biomaterial interface by quantitative proteomics.

Surface topography and texture of cell culture substrata can affect the differentiation and growth of adherent cells. The biochemical basis of the transduction of the physical and mechanical signals to cellular responses is not well understood. The lack of a systematic characterization of cell-biomaterial interaction is the major bottleneck. This study demonstrated the use of a novel subcellular fractionation method combined with quantitative MS-based proteomics to enable the robust and high-throughput analysis of proteins at the adherence interface of Madin-Darby canine kidney cells. This method revealed the enrichment of extracellular matrix proteins and membrane and stress fibers proteins at the adherence surface, whereas it shows depletion of extracellular matrix belonging to the cytoplasmic, nucleus, and lateral and apical membranes. The asymmetric distribution of proteins between apical and adherence sides was also profiled. Apart from classical proteins with clear involvement in cell-material interactions, proteins previously not known to be involved in cell attachment were also discovered.

A rare neurological complication due to lithium poisoning.

Lithium salts have been used in treatment of depression and bipolar disorder for more than 50 years. Neurotoxic side-effects such as nystagmus, ataxia, tremor, fasciculation, clonus, seizure and even coma have been well described in the literature. We present a case of generalised peripheral neuropathy following lithium intoxication. It is a rare presentation with delayed onset and characterised by a rapid downhill course. Diagnosis was confirmed by nerve conduction tests, which showed axonal neuropathy. Despite the profound neurological effects of this toxicity, it is readily reversible with supportive care and the prognosis is good.

Sensorineural Hearing Loss in Nasopharyngeal Carcinoma Survivors in the Modern Treatment Era - The Early and Late Effects of Radiation and Cisplatin.

AIMS: Hearing loss is a common debilitating complication in nasopharyngeal carcinoma (NPC) survivors. The aim of the present study was to investigate the impact of inner ear/cochlear radiation dose and cisplatin use on early and late sensorineural hearing loss (SNHL) in NPC patients treated with radiotherapy alone, concurrent chemoradiation (cCRT) and induction chemotherapy followed by cCRT (iCRT) in the intensity-modulated radiotherapy era. MATERIALS AND METHODS: The study included 81 NPC patients treated with intensity-modulated radiotherapy between 2014 and 2016. Pure tone audiometry was carried out at baseline and follow-up. The effects of cochlear/inner ear radiation and cisplatin doses on early (<12 months) and late (≥24 months) SNHL were analysed using multivariable regression after adjusting for important predictors. RESULTS: In total, 156 ears were examined. In early SNHL (n = 136), cisplatin use predicted the incidence of early high-frequency SHNL (HF-SNHL) (odds ratio 6.4, 95% confidence interval 1.7-23.9, P = 0.005). Ninety ears were analysed for late SNHL (median follow-up 38 months). Inner ear/cochlear radiation and cisplatin doses and better pre-treatment hearing were independent predictors of threshold change at 4 kHz. Every 10 Gy increase in inner ear/cochlear Dmean resulted in 5-dB and 6-dB threshold changes, respectively (cochlear Dmean: B = 0.005, 95% confidence interval 0.0004-0.009, P = 0.031; inner ear Dmean: B = 0.006, 95% confidence interval 0.001-0.010, P = 0.014). Cisplatin use was associated with late HF-SNHL (odds ratio 3.74, 95% confidence interval 1.1-12.3, P = 0.031). In the cCRT and iCRT subgroups, no cisplatin dose-dependent ototoxicity was observed. Severe (≥30 dB) late HF-SNHL occurred in 14% and 25% of the patients when the cochlear dose constraints were 40 Gy and 44 Gy, respectively. The radiotherapy-alone group did not develop severe late HF-SNHL. CONCLUSION: Cochlear/inner ear radiation dose and cisplatin use showed differential and independent ototoxicity in early and late SNHL. As cochlear/inner ear dose-dependent ototoxicity was demonstrated, the cochlear dose constraint should be as low as reasonably achievable, especially when cisplatin is also administered.

Comparing respiratory polygraphy with pulse transit time analysis versus overnight polysomnography in the diagnosis of obstructive sleep apnoea in children.

OBJECTIVE: Obstructive sleep apnea syndrome in children is associated with significant morbidity. Polysomnography is the main diagnostic tool but is time consuming and requires skilled manpower to supervise the patient overnight and hence long referral to diagnosis time. However, there are limitations and underestimation of the apnoea hyponea index (AHI) with alternative home sleep apnoea testing (HSAT), such as type 3 respiratory polygraphy (RP). Prior studies have demonstrated pulse transit time (PTT) to be a reliable indicator of cortical arousals. In this study, the use of PTT together with RP will be studied to determine whether the derived AHI is comparable to that of PSG. METHOD: Forty-five patients with suspected OSA met the inclusion criteria underwent PSG in the sleep laboratory for analysis. The raw data for either PSG or RP analysis were allocated separately to two different accredited sleep technicians. The primary outcome AHI derived from PTT with RP was compared to the AHI derived from PSG. Secondary outcomes compared were obstructive apnoea index (OAI), total hypopnoea index (THI) and arousal index (AI). Bland Altman analysis was used to compare the agreement of AHI derived from the 2 modalities and demonstrate whether RP is non inferior or equivalent to the gold standard for diagnosing OSAS. RESULTS: The patients studied had a median age of 8.8 years (range 3-17 years). The patients were not limited to certain spectrum of severity OSA and had AHI results spread from mild to severe OSA (AHI 0.4/hr to 72.2/hr). The RP with PTT-derived AHI was strongly correlated to the PSG derived AHI as seen on the Spearman plot (r = 0.98). The Bland Altman plot showed no evidence of underestimation of the AHI due to missed arousal related hypopneas. The difference of AHI derived from RP and PSG results were clinically insignificant. The differences between the PSG and RP total hypopnoea index (THI) and arousal index (AI) were also statistically insignificant. CONCLUSION: The study shows that RP with PTT can be considered a reliable diagnostic alternative compared with PSG. The role of PTT incorporated with RP was to minimize underestimation of AHI due to missed arousal associated hypopnea events. The results were apparent across mild to severe severity of OSA. There are advantages of RPs particularly in paediatrics. Overall this study offers promising preliminary insights that RP incorporated with PTT can be further explored as an acceptable home diagnostic tool for diagnosing OSA in children.

The post-antifungal effect (PAFE) of amphotericin B, nystatin, ketoconazole and 5-fluorocytosine and its impact on the colonization traits of Candida glabrata.

The post-antifungal effect (PAFE) has been shown to affect Candida pathogenicity, but there is little information on either PAFE or its association with the colonization traits of Candida glabrata. The objective of this study was to determine, in vitro, the PAFE on 14 C. glabrata isolates following exposure to amphotericin B (AMB), nystatin (NYS), ketoconazole (KETO) and 5-fluorocytosine (5FC). In addition, we evaluated the impact of PAFE on yeast adherence to buccal epithelial cells (BEC), cell-surface-hydrophobicity (CSH) and biofilm growth (BG) on denture acrylic surfaces. PAFE was induced following a 1-h exposure of yeasts to (x1-x4MIC) of AMB, NYS, KETO and 5FC in RPMI medium and, measured using automated turbidometry. The BEC adhesion, CSH and BG assays were performed by the methods of Kimura & Pearsall, Sweet et al., and Jin et al., respectively. Significant differences in PAFE (P < 0.001) were observed after exposure to AMB and NYS, but not KETO and 5FC. Following exposure to AMB, NYS, KETO and 5FC, significant inter-strain differences (P < 0.001) were observed in percentage terms in adhesion (39.0%, 43.48%, 38.28%, 35.07%) and biofilm growth (42.86%, 39.86%, 42.81%, 36.38%), respectively. Short exposure of C. glabrata to sub-cidal concentrations of antifungals modulates yeast growth and also affects some of their colonization traits.

There is no routine head and neck exam during the COVID-19 pandemic.

Head and neck examinations are commonly performed by all physicians. In the era of the COVID-19 pandemic caused by the SARS-CoV-2 virus, which has a high viral load in the upper airways, these examinations and procedures of the upper aerodigestive tract must be approached with caution. Based on experience and evidence from SARS-CoV-1 and early experience with SARS-CoV-2, we provide our perspective and guidance on mitigating transmission risk during head and neck examination, upper airway endoscopy, and head and neck mucosal surgery including tracheostomy.

Nano-scale surface morphology, wettability and osteoblast adhesion on nitrogen plasma-implanted NiTi shape memory alloy.

Plasma immersion ion implantation (PIII) is an effective method to increase the corrosion resistance and inhibit nickel release from orthopedic NiTi shape memory alloy. Nitrogen was plasma-implanted into NiTi using different pulsing frequencies to investigate the effects on the nano-scale surface morphology, structure, wettability, as well as biocompatibility. X-ray photoelectron spectroscopy (XPS) results show that the implantation depth of nitrogen increases with higher pulsing frequencies. Atomic force microscopy (AFM) discloses that the nano-scale surface roughness increases and surface features are changed from islands to spiky cones with higher pulsing frequencies. This variation in the nano surface structures leads to different surface free energy (SFE) monitored by contact angle measurements. The adhesion, spreading, and proliferation of osteoblasts on the implanted NiTi surface are assessed by cell culture tests. Our results indicate that the nano-scale surface morphology that is altered by the implantation frequencies impacts the surface free energy and wettability of the NiTi surfaces, and in turn affects the osteoblast adhesion behavior.

Effects of Salivary Mg on Head and Neck Carcinoma via TRPM7.

Magnesium (Mg) has been known to play vital roles in regulating growth and various metabolic processes. In recent years, the association between Mg and tumorigenesis has raised more and more attention. However, the effects of Mg on the progression of head and neck carcinoma (HNC), as well as the mechanism behind it, remain undefined. In this study, the roles of Mg in tumorigenic activities were tested in CAL27 and FaDu cells as well as in a xenograft tumor model in nude mice. We demonstrated that a moderate increase in extracellular Mg contributed to the proliferation, migration, and invasion of 2 HNC cell lines, while the addition of Mg in drinking water promoted the growth of xenograft tumors in mice without altering their serum Mg levels. Moreover, TRPM7, a major Mg transporter, was shown to be essential for the tumorigenic activities of HNC and the Mg-induced promotive effects on HNC cells and was further shown to be associated with the activation of AKT/mTOR (mammalian target of rapamycin) signaling. In a preliminary clinical study, we determined the Mg ion concentrations in the stimulated saliva from 72 patients with nasopharynx carcinoma and 12 healthy individuals. Our data revealed that the salivary Mg levels of subjects with nasopharynx carcinoma were significantly higher than those of the healthy controls. This is correlated with our finding showing TRPM7 to be overexpressed in tumor tissues harvested from 9 patients with HNC. Therefore, we can conclude that salivary Mg level, within a certain range, could act as a risk factor for the progression of HNC, which involves the activation of AKT/mTOR signaling pathways through the TRPM7 channel. The control of salivary Mg level and the intervention of TRPM7 should not be ignored during the study of HNC.

Epimedium-derived phytoestrogen exert beneficial effect on preventing steroid-associated osteonecrosis in rabbits with inhibition of both thrombosis and lipid-deposition.

OBJECTIVES: This study tested the effect of Epimedium-derived phytoestrogen (PE) on preventing steroid-associated osteonecrosis (ON) in rabbit model. METHODS: Thirty 28-week-old male New-Zealand white rabbits were divided into control group (CON; n=14) and PE group (PE; n=16; 5 mg/kg body weight/day) after receiving an established inductive protocol for inducing steroid-associated ON. Before and after inductive protocol, Dynamic-MRI was employed on bilateral femora for local intra-osseous perfusion, blood samples were examined for coagulation, fibrinolysis and lipid-transportation, and marrow samples were quantified for adipogenesis-gene mRNA expression. Six weeks later, bilateral femora were dissected for Micro-CT-based micro-angiography, and then ON lesion, intravascular thrombosis and extravascular fat-cell-size were examined histopathologically. RESULTS: The incidence of ON in the PE group (31%) was significantly lower than that in the CON group (93%). Compared to the CON group, local intra-osseous perfusion was maintained in the PE group. Blocked trunk vessels were seldom found in micro-angiography of the PE-treated rabbits. Thrombosis incidence and fat-cell-size were both significantly lower in the PE group than those in the CON group. During the early period after induction, indicator of coagulation, fibrinolysis, lipid-transportation and adipogenesis-gene expression were found with significantly changing pattern in the PE group compared to the CON group. CONCLUSION: PE was able to exert beneficial effect on preventing steroid-associated ON in rabbits with inhibition of both thrombosis and lipid deposition.

Surface mechanical properties, corrosion resistance, and cytocompatibility of nitrogen plasma-implanted nickel-titanium alloys: a comparative study with commonly used medical grade materials.

Stainless steel and titanium alloys are the most common metallic orthopedic materials. Recently, nickel-titanium (NiTi) shape memory alloys have attracted much attention due to their shape memory effect and super-elasticity. However, this alloy consists of equal amounts of nickel and titanium, and nickel is a well known sensitizer to cause allergy or other deleterious effects in living tissues. Nickel ion leaching is correspondingly worse if the surface corrosion resistance deteriorates. We have therefore modified the NiTi surface by nitrogen plasma immersion ion implantation (PIII). The surface chemistry and corrosion resistance of the implanted samples were studied and compared with those of the untreated NiTi alloys, stainless steel, and Ti-6Al-4V alloy serving as controls. Immersion tests were carried out to investigate the extent of nickel leaching under simulated human body conditions and cytocompatibility tests were conducted using enhanced green fluorescent protein mice osteoblasts. The X-ray photoelectron spectroscopy results reveal that a thin titanium nitride (TiN) layer with higher hardness is formed on the surface after nitrogen PIII. The corrosion resistance of the implanted sample is also superior to that of the untreated NiTi and stainless steel and comparable to that of titanium alloy. The release of nickel ions is significantly reduced compared with the untreated NiTi. The sample with surface TiN exhibits the highest amount of cell proliferation whereas stainless steel fares the worst. Compared with coatings, the plasma-implanted structure does not delaminate as easily and nitrogen PIII is a viable way to improve the properties of NiTi orthopedic implants.

Surface characteristics, biocompatibility, and mechanical properties of nickel-titanium plasma-implanted with nitrogen at different implantation voltages.

NiTi shape memory alloy is one of the promising orthopedic materials due to the unique shape memory effect and superelasticity. However, the large amount of Ni in the alloy may cause allergic reactions and toxic effects thereby limiting its applications. In this work, the surface of NiTi alloy was modified by nitrogen plasma immersion ion implantation (N-PIII) at various voltages. The materials were characterized by X-ray photoelectron spectroscopy (XPS). The topography and roughness before and after N-PIII were measured by atomic force microscope. The effects of the modified surfaces on nickel release and cytotoxicity were assessed by immersion tests and cell cultures. The XPS results reveal that near-surface Ni concentration is significantly reduced by PIII and the surface TiN layer suppresses nickel release and favors osteoblast proliferation, especially for samples implanted at higher voltages. The surfaces produced at higher voltages of 30 and 40 kV show better adhesion ability to osteoblasts compared to the unimplanted and 20 kV PIII samples. The effects of heating during PIII on the phase transformation behavior and cyclic deformation response of the materials were investigated by differential scanning calorimetry and three-point bending tests. Our results show that N-PIII conducted using the proper conditions improves the biocompatibility and mechanical properties of the NiTi alloy significantly.

Nickel release behavior, cytocompatibility, and superelasticity of oxidized porous single-phase NiTi.

Porous NiTi shape memory alloys are one of the promising biomaterials for surgical implants because of their unique shape memory effects and porous structure with open pores. However, the complex surface morphology and larger area of porous NiTi compared to dense NiTi make it more vulnerable from the viewpoint of release of nickel, which can cause deleterious effects in the human body. It is also more difficult to modify the exposed surfaces of a porous structure using conventional surface modification technologies. In this work, oxidation in conjunction with postreaction heat treatment was used to modify the surfaces of porous single-phase NiTi prepared by capsule-free hot isostatic pressing to mitigate Ni leaching and enhance the surface properties. Differential scanning calorimetry thermal analysis, uniaxial compression tests, inductively-coupled plasma mass spectrometry, and cell cultures reveal that porous NiTi alloys oxidized at 450 degrees C for 1 h have an austenite transition temperature below 37 degrees C, excellent superelasticity, lower nickel release, and no cytotoxicity.

Surface structure and properties of biomedical NiTi shape memory alloy after Fenton's oxidation.

Fenton's oxidation is traditionally used to remove inorganic and organic pollutants from water in waster water treatment. It is an advanced oxidation process in which H2O2 is catalytically decomposed by ferrous irons into hydroxyl radicals (*OH) which have a higher oxidation potential (2.8V) than H2O2. In the work reported here, we for the first time use Fenton's oxidation to modify the surface of biomedical NiTi shape memory alloy (SMA). The influences of Fenton's oxidation on the surface microstructure, blood compatibility, leaching of harmful Ni ions and corrosion resistance in simulated body fluids is assessed using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, inductively coupled plasma mass spectrometry, electrochemical tests, hemolysis analysis and the blood platelet adhesion test. The mechanical stability of the surface titania film produced by Fenton's oxidation as well as their effects on the shape memory behavior of the SMA are studied by bending tests. Our results show that Fenton's oxidation produces a novel nanostructured titania gel film with a graded structure on the NiTi substrate without an intermediate Ni-rich layer that is typical of high-temperature oxidation. Moreover, there is a clear Ni-free zone near the top surface of the titania film. The surface structural changes introduced by Fenton's oxidation improve the electrochemical corrosion resistance and mitigate Ni release. The latter effects are comparable to those observed after oxygen plasma immersion ion implantation reported previously and better than those of high-temperature oxidation. Aging in boiling water improves the crystallinity of the titania film and further reduces Ni leaching. Blood platelet adhesion is remarkably reduced after Fenton's oxidation, suggesting that the treated SMA has improved thrombo resistance. Enhancement of blood compatibility is believed to stem from the improved hemolysis resistance, the surface wettability and the intrinsic electrical characteristics of the titania film. The titania film produced by Fenton's oxidation has good mechanical stability and does not adversely impact the shape memory behavior of NiTi. Our work suggests that Fenton's oxidation is a promising low-temperature, low-cost surface modification method for improving the surface properties of biomedical NiTi SMA.

Construction of poly (vinyl alcohol)/poly (lactide-glycolide acid)/vancomycin nanoparticles on titanium for enhancing the surface self-antibacterial activity and cytocompatibility.

Comparing with traditional drug dosage form, controlled release systems offer more effective and favorable route to deliver drugs in optimum dose to specific sites with long term release duration. In this work, an effective drug delivery system composed of poly (vinyl alcohol) (PVA)/poly (lactide-glycolide acid) (PLGA) nanoparticles (NPs) with encapsulated vancomycin (Van), is constructed on the surface of biomedical titanium. The PVA/PLGA/Van NPs synthesized via double emulsion route are grafted onto the surface of titanium plates modified by alkaline-heat treatment and subsequent aminopropyltriethoxysilane (APTES) deposition. In vitro tests disclose that NPs can release a small amount of drugs continuously due to the slow swelling or hydrolysis of polymer chain segments as the immersion time increases. As the pH value reduces, the ester bonds rupture with releasing more drugs, which is why this drug delivery system exhibits the highest antibacterial efficiency at the lowest pH value of 4.5 in this work. Cell culture results reveal that this smart surface system on titanium facilitates the cell attachment and proliferation on implants. Hence, this pH controlled drug delivery system can be successfully applied as a bio-platform for improving both the osteoblasts adhesion and antibacterial activity of metallic implants.

Construction of N-halamine labeled silica/zinc oxide hybrid nanoparticles for enhancing antibacterial ability of Ti implants.

The traditional antibiotic treatment for bacterial infections often induces antibiotic resistance in bacteria. In this work, we developed hybrid nanoparticles (NPs) with a self-antibacterial ability on Ti implants using monodispersed polystyrene-acrylic acid (PSA) nanoparticles as colloidal templates followed by the electrostatic adsorption of zinc oxide (ZnO) and the subsequent deposition of silica (SiO2) membrane on the outside. These synthesized PSA-ZnO-SiO2 NPs were pretreated by 5,5-dimethylhydantoin (DMH) before chlorination in a diluted NaClO solution. These nanoparticles (PSA-ZnO-SiO2-DMH) were subsequently labeled by N-halamines and then immobilized on the surface of titanium plates through hydrogen bonding. Field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS) were utilized to characterize the modified surface. Antibacterial tests disclosed that the PSA-ZnO-SiO2-DMH-Cl NPs modified surface exhibited excellent antibacterial activity against both Pseudomonas aeruginosa (P.au), Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In vitro cell culture results revealed that PSA-ZnO-SiO2-DMH-Cl had no obvious cytotoxicity for an MC3T3-E1 preosteoblast. This novel surface system provides a promising self-antibacterial bioplatform for metallic implants without using antibiotics.

Construction of poly(lactic-co-glycolic acid)/ZnO nanorods/Ag nanoparticles hybrid coating on Ti implants for enhanced antibacterial activity and biocompatibility.

Poly(lactic-co-glycolic acid)/Ag/ZnO nanorods coating were successfully prepared on the surface of Ti metallic implants using a hydrothermal method and subsequent spin-coating of mixtures of poly(lactic-co-glycolic acid) and silver nanoparticles. The poly(lactic-co-glycolic acid)/Ag/ZnO nanorods coating exhibited excellent antibacterial efficacy of over 96% against both Staphylococcus aureus and Escherichia coli when the initial content of Ag nanoparticles was over 3wt%. In addition, the release of both silver and zinc could last for over a hundred days due to the enwrapping of poly(lactic-co-glycolic acid). Proliferation of mouse calvarial cells exhibited minimal cytotoxicity on the poly(lactic-co-glycolic acid)/Ag/ZnO coating with an initial content of Ag nanoparticles of 1wt% and 3wt%, while it inhibited cell proliferation once this value was increased to 6wt%. The results revealed that this poly(lactic-co-glycolic acid)/Ag/ZnO composite could provide a long-lasting antibacterial approach and good cytocompatibility, thus exhibiting considerable potential for biomedical application in orthopedic and dental implants with excellent self-antibacterial activity and good biocompatibility.