Alloyed Trimetallic Nanocomposite as an Efficient and Recyclable Solid Matrix for Ideonella sakaiensis Lipase Immobilization.

In this work, a trimetallic (Ni/Co/Zn) organic framework (tMOF), synthesized by a solvothermal method, was calcinated at 400 and 600 °C and the final products were used as a support for lipase immobilization. The material annealed at 400 °C (Ni-Co-Zn@400) had an improved surface area (66.01 m2/g) and pore volume (0.194 cm3/g), which showed the highest enzyme loading capacity (301 mg/g) with a specific activity of 0.196 U/mg, and could protect the enzyme against thermal denaturation at 65 °C. The optimal pH and temperature for the lipase were 8.0 and 45 °C but could tolerate pH levels 7.0-8.0 and temperatures 40-60 °C. Moreover, the immobilized enzyme (Ni-Co-Zn@Lipase, Ni-Co-Zn@400@Lipase, or Ni-Co-Zn@600@Lipase) could be recovered and reused for over seven cycles maintaining 80, 90, and 11% of its original activity and maintained a residual activity >90% after 40 storage days. The remarkable thermostability and storage stability of the immobilized lipase suggest that the rigid structure of the support acted as a protective shield against denaturation, while the improved pH tolerance toward the alkaline range indicates a shift in the ionization state attributed to unequal partitioning of hydroxyl and hydrogen ions within the microenvironment of the active site, suggesting that acidic residues may have been involved in forming an enzyme-support bond. The high enzyme loading capacity, specific activity, encouraging stability, and high recoverability of the tMOF@Lipase indicate that a multimetallic MOF could be a better platform for efficient enzyme immobilization.

Preparation of Multifunctional Hydrogels with In Situ Dual Network Structure and Promotion of Wound Healing.

As an emerging biomedical material, wound dressings play an important therapeutic function in the process of wound healing. It can provide an ideal healing environment while protecting the wound from a complex external environment. A hydrogel wound dressing composed of tilapia skin gelatin (Tsg) and fucoidan (Fuc) was designed in this article to enhance the microenvironment of wound treatment and stimulate wound healing. By mixing horseradish peroxidase (HRP), hydrogen peroxide (H2O2), tilapia skin gelatin-tyramine (Tsg-Tyr), and carboxylated fucoidan-tyramine in agarose (Aga), using the catalytic cross-linking of HRP/H2O2 and the sol-gel transformation of Aga, a novel gelatin-fucoidan (TF) double network hydrogel wound dressing was constructed. The TF hydrogels have a fast and adjustable gelation time, and the addition of Aga further enhances the stability of the hydrogels. Moreover, Tsg and Fuc are coordinated with each other in terms of biological efficacy, and the TF hydrogel demonstrated excellent antioxidant properties and biocompatibility in vitro. Also, in vivo wound healing experiments showed that the TF hydrogel could effectively accelerate wound healing, reduce wound microbial colonization, alleviate inflammation, and promote collagen deposition and angiogenesis. In conclusion, TF hydrogel wound dressings have the potential to replace traditional dressings in wound healing.

COVID-19 vaccination affects short-term anti-coagulation levels in warfarin treatment.

Vaccines against SARS-CoV-2 have been recommended across the world, yet no study has investigated whether COVID-19 vaccination influences short-term warfarin anti-coagulation levels. Patients on stable warfarin treatment who received anti-SARS-CoV-2 vaccination were prospectively enrolled and followed up for three months. INR values less than 10 days before vaccination (baseline), 3-5 days (short-term) and 6-14 days (medium-term) after vaccination were recorded as INR0, INR1, and INR2, respectively. The variations of INR values within individuals were compared, and the linear mixed effect model was used to evaluate the variations of INR values at different time points. Logistic regression analysis was performed to determine covariates related to INR variations after COVID-19 vaccination. Vaccination safety was also monitored. There was a significant difference in INR values between INR0 and INR1 (2.15 vs. 2.26, p = 0.003), yet no marked difference was found between INR0 and INR2. The linear mixed effect model also demonstrated that INR variation was significant in short-term but not in medium-term or long-term period after vaccination. Logistic regression analysis showed that no investigated covariates, including age, vaccine dose, genetic polymorphisms of VKORC1 and CYP2C9 etc., were associated with short-term INR variations. Two patients (2.11%) reported gingival hemorrhage in the short-term due to increased INR values. The overall safety of COVID-19 vaccines for patients on warfarin was satisfying. COVID-19 vaccines may significantly influence warfarin anticoagulation levels 3-5 days after vaccination. We recommend patients on warfarin to perform at least one INR monitoring within the first week after COVID-19 vaccination.

Continuous Transformation from Membrane-Less Coacervates to Membranized Coacervates and Giant Vesicles: Toward Multicompartmental Protocells with Complex (Membrane) Architectures.

The membranization of membrane-less coacervates paves the way for the exploitation of complex protocells with regard to structural and cell-like functional behaviors. However, the controlled transformation from membranized coacervates to vesicles remains a challenge. This can provide stable (multi)phase and (multi)compartmental architectures through the reconfiguration of coacervate droplets in the presence of (bioactive) polymers, bio(macro)molecules and/or nanoobjects. Herein, we present a continuous protocell transformation from membrane-less coacervates to membranized coacervates and, ultimately, to giant hybrid vesicles. This transformation process is orchestrated by altering the balance of non-covalent interactions through varying concentrations of an anionic terpolymer, leading to dynamic processes such as spontaneous membranization of terpolymer nanoparticles at the coacervate surface, disassembly of the coacervate phase mediated by the excess anionic charge, and the redistribution of coacervate components in membrane. The diverse protocells during the transformation course provide distinct structural features and molecular permeability. Notably, the introduction of multiphase coacervates in this continuous transformation process signifies advancements toward the creation of synthetic cells with different diffusible compartments. Our findings emphasize the highly controlled continuous structural reorganization of coacervate protocells and represents a novel step toward the development of advanced and sophisticated synthetic protocells with more precise compositions and complex (membrane) structures.

Artificial Intelligence-Assisted Digital Immunoassay Based on a Programmable-Particle-Decoding Technique for Multitarget Ultrasensitive Detection.

The development of a multitarget ultrasensitive immunoassay is significant to fields such as medical research, clinical diagnosis, and food safety inspection. In this study, an artificial intelligence (AI)-assisted programmable-particle-decoding technique (APT)-based digital immunoassay system was developed to perform multitarget ultrasensitive detection. Multitarget was encoded by programmable polystyrene (PS) microspheres with different characteristics (particle size and number), and subsequent visible signals were recorded under an optical microscope after the immune reaction. The resultant images were further analyzed using a customized, AI-based computer vision technique to decode the intrinsic properties of polystyrene microspheres and to reveal the types and concentrations of targets. Our strategy has successfully detected multiple inflammatory markers in clinical serum and antibiotics with a broad detection range from pg/mL to µg/mL without extra signal amplification and conversion. An AI-based digital immunoassay system exhibits great potential to be used for the next generation of multitarget detection in disease screening for candidate patients.

Construction of Membraneless and Multicompartmentalized Coacervate Protocells Controlling a Cell Metabolism-like Cascade Reaction.

In recent years, there has been growing attention to designing synthetic protocells, capable of mimicking micrometric and multicompartmental structures and highly complex physicochemical and biological processes with spatiotemporal control. Controlling metabolism-like cascade reactions in coacervate protocells is still challenging since signal transduction has to be involved in sequential and parallelized actions mediated by a pH change. Herein, we report the hierarchical construction of membraneless and multicompartmentalized protocells composed of (i) a cytosol-like scaffold based on complex coacervate droplets stable under flow conditions, (ii) enzyme-active artificial organelles and a substrate nanoreservoir capable of triggering a cascade reaction between them in response to a pH increase, and (iii) a signal transduction component based on the urease enzyme capable of the conversion of an exogenous biological fuel (urea) into an endogenous signal (ammonia and pH increase). Overall, this strategy allows a synergistic communication between their components within the membraneless and multicompartment protocells and, thus, metabolism-like enzymatic cascade reactions. This signal communication is transmitted through a scaffold protocell from an "inactive state" (nonfluorescent protocell) to an "active state" (fluorescent protocell capable of consuming stored metabolites).

Synthesis and Characterization of a New Copolymer Consisting of Polyamide 1210 and Reactive Phosphorus-Nitrogen Flame-Retardant.

The thermal stability and reactivity of organophosphorus flame-retardants play a critical role in synthesizing copolymerized flame-retardant polyamides. Herein, this work successfully synthesizes a flame-retardant CEPPA-DDA salt (CDS) with both good thermal stability and high reactivity by reacting 2-carboxyethyl phenyl phosphonic acid (CEPPA) with 1,12-dodecanediamine (DDA). Flame-retardant polyamide 1210 (FRPA) is further prepared by copolymerizing the CDS, DDA, and sebacic acid (SEA). The test results show that the introduction of CDS can significantly improve the flame-retardant properties of FRPA. Specifically, the flame-retardant polyamide 1210 (FRPA-7) with 7 wt% CDS addition can reach V-0 grade according to UL-94 standard, accompanying limiting oxygen index value of 30.2% and tensile strength of 38.62 MPa. Compared with pure polyamide 1210, the peak heat release rate and total heat release rate of FRPA-7 reduce by 24.11% and 9.40%, respectively. This study provides a simple strategy to prepare flame-retardant polyamides with high flame retardancy and good mechanical properties, which are expected to show great potentials in future industrial applications.

Serum zinc and periodontitis in non-diabetic smoking and non-smoking adults: NHANES 2011-2014.

OBJECTIVE: This study aimed to evaluate the association of serum zinc with periodontitis in non-diabetics based on smoking status, using a representative sample of adults in the United States. METHODS: A total of 1051 participants who underwent full-mouth periodontal examination and serum zinc testing were enrolled from NHANES 2011 to 2014. The covariate-adjusted association of serum zinc concentrations with periodontitis was explored using multivariable logistic regression, restricted cubic spines, and sensitivity analysis. RESULTS: The mean age of the 1051 adults was 54.5 years, 59.37% were male, and 20.65% had periodontitis. Analysis of the results showed that serum zinc was associated with periodontitis. The overall adjusted odds of periodontitis were 9% (odds ratio [OR]: 0.91; 95% confidence interval [CI]: 0.83-1.00) and 14% (OR: 0.86; 95% CI: 0.75-0.98) for nonsmokers and smokers, respectively. Smokers with T3 serum zinc exhibited a 53% reduction in the fully adjusted odds of periodontitis (OR: 0.47; 95% CI: 0.23-0.96), when compared to the reference group (T1 serum zinc), with serum zinc as the categorical variable. CONCLUSIONS: Serum zinc levels were associated with the risk of periodontitis in non-diabetic smokers but not non-smokers.

Comparative evaluation of four treatments for postorthodontic white spot lesions: a randomized controlled trial.

OBJECTIVES: To evaluate the treatment efficacy of fluoride toothpaste alone and those of adjunctive use of resin infiltration, sodium fluoride varnish, and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on white spot lesions (WSLs). MATERIALS AND METHODS: Seventy-nine patients (356 teeth) with WSLs after orthodontic treatment were randomly allocated into four groups. The WSLs of the participants received resin infiltration only at baseline, and the other groups received fluoride varnish, CPP-ACP mousse, and placebo treatment every 6 months, respectively. A toothpaste containing 1400 ppm fluoride and toothbrushes were distributed to all participants, and oral hygiene instructions were provided. Photos of the teeth with WSL were taken to compare the change between groups which was measured by ImageJ software. RESULTS: Twelve months later, different degrees of reduction in the area of WSLs were observed in all groups. The percentage of lesion area reduction in WSLs in the resin infiltration group was 46.6%, which was significantly higher than that in fluoride varnish group (26.6%), CPP-ACP group (28.6%), and control group (29.8%), and the differences were statistically significant (p < 0.001). CONCLUSIONS: This study shows that after 1-year follow-up, the use of fluoride toothpaste, with or without the use of fluoride varnish or CPP-ACP, can reduce the area of WSLs. While resin infiltration can immediately improve dental aesthetics and continuously improved in 12 months, resin infiltration group showed much better results than other groups. TRIAL REGISTRATION: Clinical Trials Registration Number: ChiCTR2000032516. CLINICAL SIGNIFICANCE: The use of fluoride toothpaste, with or without adjunctive use of fluoride varnish and CPP-ACP, can reduce the area of WSLs, while resin infiltration treatment has additional effect and can immediately improve dental aesthetics.

Endodontic management of maxillary first molar with protostylid: a rare case report.

BACKGROUND: A protostylid is a relatively rare dental developmental aberration characterized as an extra cusp located on the mesial half of the buccal surface of the molars. A protostylid is rarely to be reported due to its low rate of occurrence. This case report describes a patient referred for endodontic treatment due to the presence of a protostylid on the buccal surface of the maxillary first molar that induced apical periodontitis. CASE PRESENTATION: A 53-year-old female reported a 3-month history of pain of chewing with her upper left posterior teeth over 3 months. In the clinical examination, an abraded anomalous cusp-like structure was found on the buccal surface of tooth 26, Cone beam computed tomography (CBCT) revealed a supernumerary cusp with an intact root canal inside, which was fused with the mesiobuccal (MB) root canal in the middle of the root. In addition, extensive periapical radiolucency was observed around tooth 26. The tooth was diagnosed as apical periodontitis, and endodontic treatment was performed. The initial lesion in tooth 26 gradually healed over 1 year of observation. CONCLUSIONS: To our knowledge, this case is the first to describe the endodontic management of a maxillary first molar with a protostylid and advances our understanding of supernumerary cusps. This case provides a reference for the treatment of protostylid.

Zero-Interfacing µHPLC to ICPMS.

The chromatography-mass spectrometry hyphenated technique is the most widely adopted tool for quantifying trace analytes in a complex biosample. One issue we frequently encountered, however, is that the separated analyte-containing chromatographic peaks broaden and even remix prior to mass spectrometric quantification due to the inevitable molecular diffusion within the dead-volume introduced by hyphenation. We developed a zero-interfacing approach for coupling microbore (µ) HPLC with inductively coupled plasma mass spectrometry (ICPMS). Zero-interfacing µHPLC to ICPMS has been achieved by a column-nebulizer assembly (COL-NEB) of a self-designed glass framework with a tapered nozzle, in which a capillary chromatographic column can be harbored while an Ar gas flow is blown through the nozzle mouth. The COL-NEB can be positioned just before the base of the Ar-ICP serving as the central sampling channel of a conventional Ar-ICP torch for online nebulization and transportation of the analytes separated on µHPLC into ICPMS, maintaining the molecular resolution obtained on µHPLC and the limit of detection (LOD) of ICPMS. For example, the full width at half-maximum of a SLUGT peptide chromatographic peak was reduced to 1.71 ± 0.07 s (n = 5) with a 0.72 fg LOD (3σ) of 80Se. Moreover, at least 32 Se-containing peptides were determined in the trypsin lysate of the water-soluble fraction (≥3000 MW) from Se-enriched yeast CRM SELM-1 within a 10 min run, the highest record to date. We believe such an approach paves the way to determining accurate information on a heteroatom and its binding biomolecules that play key roles during life processes.

Controlling Properties and Functions of Polymer Gels Using Photochemical Reactions.

Photoresponsive polymer gels have attracted increasing interest owing to their potential applications in healable materials, drug release systems, and extracellular matrices. Because polymer gels provide suitable environments for photochemical reactions, their properties and functions can be controlled with light with a high spatiotemporal resolution. Herein, the design of photoresponsive polymer gels based on different types of photochemical reactions is introduced. The mechanism and applications of irreversible photoreactions, such as photoinduced free-radical polymerization, photoinduced click reactions, and photolysis, as well as reversible photoreactions such as photoinduced reversible cycloadditions, reversible photosubstitution of metal complexes, and photoinduced metathesis are reviewed. The remaining challenges of photoresponsive polymer gels are also discussed.

A test prototype of a novel flexible video laryngoscope and preliminary verification in a difficult airway management simulator.

BACKGROUND: To verify a test prototype of a novel flexible video laryngoscope in a difficult airway management simulator and to compare the efficacy of the flexible video laryngoscope with that of a conventional video laryngoscope. METHODS: Fifteen clinical anesthesiologists performed endotracheal intubation with a flexible video laryngoscope and a conventional video laryngoscope in a difficult airway management simulator in the neutral position with intermediate and difficult mouth opening. The rate of intubation success, intubation time, and classification of glottic exposure were recorded. After endotracheal intubation, participants were asked to assess the difficulty of intubation of the two laryngoscopes. RESULTS: The success rate of endotracheal intubation with flexible video laryngoscope was significantly higher than that with video laryngoscope in neutral positions with both intermediate (P = 0.025) and difficult (P = 0.005) mouth opening. The Cormack Lehane score of the flexible video laryngoscope was significantly lower than that of the video laryngoscope in the neutral position with intermediate mouth opening (P < 0.001) and difficult mouth opening (P < 0.001). There was no significant difference in intubation time in the neutral position with intermediate mouth opening (P = 0.460) or difficult mouth opening (P = 0.078). The difficulty score of endotracheal intubations with the flexible video laryngoscope was also significantly lower than that of the video laryngoscope in the neutral position with intermediate mouth opening (P = 0.001) and difficult mouth opening (P = 0.001). CONCLUSIONS: Compared with conventional video laryngoscopy, flexible video laryngoscopy can provide superior glottic exposure and improve the success rate of intubation in a difficult airway management simulator.

Mechanism and quantitative assessment of saturation transfer for water-based detection of the aliphatic protons in carbohydrate polymers.

PURPOSE: CEST MRI experiments of mobile macromolecules, for example, proteins, carbohydrates, and phospholipids, often show signals due to saturation transfer from aliphatic protons to water. Currently, the mechanism of this nuclear Overhauser effect (NOE)-based transfer pathway is not completely understood and could be due either to NOEs directly to bound water or NOEs relayed intramolecularly via exchangeable protons. We used glycogen as a model system to investigate this saturation transfer pathway in sugar polymer solution. METHODS: To determine whether proton exchange affected saturation transfer, saturation spectra (Z-spectra) were measured for glycogen solutions of different pH, D2 O/H2 O ratio, and glycogen particle size. A theoretical model was derived to analytically describe the NOE-based signals in these spectra. Numerical simulations were performed to verify this theory, which was further tested by fitting experimental data for different exchange regimes. RESULTS: Signal intensities of aliphatic NOEs in Z-spectra of glycogen in D2 O solution were influenced by hydroxyl proton exchange rates, whereas those in H2 O were not. This indicates that the primary transfer pathway is an exchange-relayed NOE from these aliphatic protons to neighboring hydroxyl protons, followed by the exchange to water protons. Experimental data for glycogen solutions in D2 O and H2 O could be analyzed successfully using an analytical theory derived for such relayed NOE transfer, which was further validated using numerical simulations with the Bloch equations. CONCLUSION: The predominant mechanism underlying aliphatic signals in Z-spectra of mobile carbohydrate polymers is intramolecular relayed NOE transfer followed by proton exchange.

The differences in characteristics of extracellular polymeric substances of flocs and anammox granules impacted aggregation.

Extracellular polymeric substances (EPS) are considered crucial components in the formation of microbial aggregates such as biofilms, flocs and granules. However, the role of EPS in sludge aggregation is still unclear. In this study, the differences in EPS characteristics of anammox granular sludge (AG), anammox floc sludge (AF) and activated floc sludge (AS) were investigated to clarify its role in granular aggregation. The results showed that the flocculation ability of EPS extracted from AG (62.8 ± 2.3%) was notably higher than that of EPS extracted from AF (35.7 ± 1.7%) and AS (17.3 ± 1.5%). The zeta potential and hydrophobicity of EPS showed the same tendency. In addition, the PN/PS ratio of AG, AF and AS were 7.66, 4.62 and 3.93, respectively. FTIR, XPS and 3D-EEM fluorescence spectra results revealed that anammox granular sludge has a higher ratio of hydrophobic groups, α-helixs/(ß-sheets and random coils), intermolecular hydrogen bonds, and aromatic amino acids, and a lower ratio of electronegative groups. Anammox granular sludge exhibited high aggregation ability, because its EPS had higher zeta potential, hydrophobicity and intermolecular hydrogen bond ratio. This work provides a better understanding of the high aggregation ability of anammox granules and a theoretical basis for improving granules proportion and retention ability of microbes in reactor system.

Serum 25-hydroxyvitamin D is negatively associated with severe periodontitis: a cross-sectional study.

BACKGROUND: Periodontitis can lead to the destruction of periodontium and adversely influence the overall health, wellbeing, and quality of life. However, studies on the relationship between severe periodontitis and serum 25-hydroxyvitamin D [25(OH)D] are limited. This study is designed to explore the relationship between 25(OH)D and severe periodontitis. METHODS: A cross-section study of 2928 participants enrolled from the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2014 was conducted. The periodontal examination was performed using a total oral periodontal examination program, and probe measurements were collected at six sites per tooth in NHANES. Severe periodontitis was characterized as: ≥ 2 interproximal sites with attachment loss (AL) ≥ 6 mm (not on the same tooth) and ≥ 1 interproximal site with probing depth (PD) ≥ 5 mm. Severe periodontitis and serum 25(OH)D were the dependent and independent variables, respectively. Univariate, multivariate, and subgroup analyses were performed to explore the relationship between severe periodontitis and serum 25(OH)D. RESULTS: Among the 2928 participants, the average age of the population was 50 ± 13.71 years old, with 1425 (48.67%) males, 316 (10.79%) exhibited severe periodontitis. Serum 25(OH)D showed a significantly negative association with severe periodontitis after adjusting all variables (OR 0.75, 95% CI 0.63-0.89). In addition, severe periodontitis has a nonlinear relationship with serum 25(OH)D, whoes inflection point was 102 (nmol/L). On the left side of the inflection point (25(OH)D ≤ 102 nmol/L), the effect size was 0.98 and 95%CI was 0.98-0.99 (25(OH)D per 1 nmol/L increments). On the right side of the inflection point (25(OH)D > 102 nmol/L), the effect size was 0.99 and 95% CI was 0.98-1.01. The subgroup analysis showed pronounced changes in non-Hispanic white, alcohol consumption, diabetes, and health insurance. CONCLUSION: Serum 25 (OH) D in relation to severe periodontitis is nonlinear in our study.When serum 25 (OH) D is less than 102 nmol/L, serum 25 (OH) D is negatively associated with severe periodontitis.

A two-week single-group longitudinal test of a new sonic-powered toothbrush simulating the 'bass brushing technique' with tapered bristles on the brush head for reduction of dental plaque and gingivitis.

OBJECTIVE: To investigate the effect of a new powered toothbrush with tapered bristles on the brush head for the reduction of dental plaque and gingivitis. METHODS: This was a single-centre, single-group, longitudinal clinical trial. Thirty-two participants who were typical manual toothbrush users were recruited and assigned the sonic-powered brush. Interviews were arranged on the 1st , 4th , and 15th days which represented the baseline (T1 ), middle (T2 ) and final (T3 ) time points, respectively. At each visit, the plaque index (PlI), gingival index (GI), bleeding on probing (BOP) and probing depth (PD) were recorded for the Ramfjord index teeth, gingival crevicular fluid(GCF) samples were collected and the proportions of eight periodontal pathogenic bacteria were analysed. Repeated-measures analysis of variance (ANOVA) was used for comparisons at different time points. RESULTS: PlI was significantly reduced by 41.67% from T1 to T2 (p<0.001) and decreased by 18.57% from T2 to T3 (p=0.003). GI also varied significantly from T1 to T2 (p=0.018) and T1 to T3 (p=0.037). A 35.86% reduction in the BOP percentage occurred after using the sonic-powered toothbrush for 3 days (p=0.001). However, no significant difference was observed in the mean values of PD at different examination intervals (p=0.529). There was no significant difference in the proportions of bacteria between T1 and T3 (p>0.05). CONCLUSION: This research demonstrated the efficacy of the sonic-powered brush handle together with tapered bristles on the brush in reducing plaque and gingivitis within a short time period.

Enhanced Hemocompatibility and In Vivo Analytical Accuracy of Intravascular Potentiometric Carbon Dioxide Sensors via Nitric Oxide Release.

In this letter, the innate ability of nitric oxide (NO) to inhibit platelet activation/adhesion/thrombus formation is employed to improve the hemocompatibility and in vivo accuracy of an intravascular (IV) potentiometric PCO2 (partial pressure of carbon dioxide) sensor. The catheter-type sensor is fabricated by impregnating a segment of dual lumen silicone tubing with a proton ionophore, plasticizer, and lipophilic cation-exchanger. Subsequent filling of bicarbonate and strong buffer solutions and placement of Ag/AgCl reference electrode wires within each lumen, respectively, enables measurement of the membrane potential difference across the inner wall of the tube, with this potential changing as a function of the logarithm of sample PCO2. The dual lumen device is further encapsulated within a S-nitroso-N-acetyl-DL-penicillamine (SNAP)-doped silicone tube that releases physiological levels of NO. The NO releasing sensor exhibits near-Nernstian sensitivity toward PCO2 (slope = 59.31 ± 0.78 mV/decade) and low drift rates (<2 mV/24 h after initial equilibration). In vivo evaluation of the NO releasing sensors, performed in the arteries and veins of anesthetized pigs for 20 h, shows enhanced accuracy (vs non-NO releasing sensors) when benchmarked to measurements of discrete blood samples made with a commercial blood gas analyzer. The accurate, continuous monitoring of blood PCO2 levels achieved with this new IV NO releasing PCO2 sensor configuration could help better manage hospitalized patients in critical care units.

The association between serum 25-hydroxyvitamin D levels and dental caries in US adults.

OBJECTIVES: We investigated whether 25-hydroxyvitamin D concentration is independently associated with dental caries among adults in the United States. SUBJECTS AND METHODS: This investigation was a cross-sectional study. A total of 4,244 participants (aged 20-80 years) were enrolled through the 2007-2008 National Health and Nutrition Examination Survey (NHANES). Serum 25-hydroxyvitamin D was categorized into four groups based on previous studies: normal (≥75 nmol/ml), insufficient (50-74.9 nmol/ml), deficient (25-49.9 nmol/ml), and severely deficient (<25 nmol/ml). The dependent and independent variables included dental caries and serum 25-hydroxyvitamin D, respectively. The data were analyzed using univariate analyses, multivariable-adjusted analyses, and subgroup analyses. RESULTS: The fully adjusted model showed that 25-hydroxyvitamin D levels were negatively associated with dental caries after adjusting for the confounders (OR = 0.93, 95% CI 0.89 to 0.98). Compared with the normal group, the likelihood of dental caries was 2.48, 1.29, and 1.43 times higher in the severely deficient, deficient, and insufficient groups, respectively. CONCLUSIONS: Our findings suggest that serum 25-hydroxyvitamin D levels are significantly associated with the occurrence of dental caries among US adults.

Root dentine thickness of danger zone in mesial roots of mandibular first molars.

BACKGROUND: Better understanding of the danger zone anatomy in mesial roots (MRs) of mandibular first molars (MFMs) may serve to decrease the risk of mishaps. This study aimed to measure the minimal distal dentine thicknesses of danger zone in MRs of MFMs in a native Chinese population using cone-beam computed tomography (CBCT). METHODS: CBCT images of 1792 MFMs from 898 Chinese patients were analyzed. The minimal distal dentine thicknesses of the mesiobuccal (MB) and mesiolingual (ML) canals below the furcation 1, 2, 3, 4, 5 mm were measured. The association between the minimal distal dentine thicknesses and the root lengths, patient's age and gender, side were assessed. RESULTS: The minimal distal dentine thicknesses of MB and ML canals are located 3 ∼ 4 mm below the furcation for both men and women. There are no differences between MB and ML canals, while the minimal distal dentine thicknesses of MB and ML canals were higher in men than women (P < 0.05), except at 1 and 3 mm of ML canals (P > 0.05). The minimal distal dentine thicknesses of MB and ML canals increased with age in both men and women at each location (P < 0.05). The minimum distal dentine thickness at every location were significantly different between long teeth and short teeth both in men and women (P < 0.05), with short teeth having the smallest mean values. There are no significant differences between two sides (P > 0.05). CONCLUSIONS: The minimal distal dentine thicknesses of MRs in MSMs have close correlation with root length, patient's age and gender.