Heterozygous Seryl-tRNA Synthetase 1 Variants Cause Charcot-Marie-Tooth Disease.

OBJECTIVE: Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT. METHODS: Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays. RESULTS: Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation. INTERPRETATION: Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.

The survival of periodontally treated molars in long-term maintenance: A systematic review and meta-analysis.

AIM: This systematic review and meta-analysis aimed to determine the survival of periodontally treated molars during maintenance care and identify the risk factors associated with molar loss among patients with periodontitis who received professional periodontal therapy and maintenance. MATERIALS AND METHODS: Longitudinal studies with a minimum follow-up duration of 5 years published until 28 August 2023 were retrieved from the following databases: the Cochrane Library, Embase, MEDLINE and Web of Science. All included studies reported data on molar retention. Meta-analysis was performed using Review Manager 5.4. A modified version of the Newcastle-Ottawa Scale was used to evaluate the study quality. Statistical results of analyses of the overall survival rate and molar loss are presented as estimated standardized mean differences, whereas the results of the analyses of risk factors are presented as risk ratios with 95% confidence intervals (95% CIs). RESULTS: From among the 1323 potentially eligible reports, 41 studies (5584 patients, 29,908 molars retained at the beginning of maintenance therapy, mean follow-up duration of 14.7 years) were included. The pooled survival rate of the molars during maintenance therapy was 82% (95% CI: 80%-84%). The average loss of molars was 0.05 per patient per year (95% CI: 0.04-0.06) among the patients receiving long-term periodontal maintenance (PM) therapy. Fifteen factors were examined in this meta-analysis. Six patient-related factors (older age, lack of compliance, smoking, bruxism, diabetes and lack of private insurance) and five tooth-related factors (maxillary location, high probing pocket depth, furcation involvement, higher mobility and lack of pulpal vitality) were identified as risk factors for molar loss during maintenance therapy. CONCLUSIONS: The findings of the present study suggest that the long-term retention of periodontally compromised molars can be achieved. The average number of molars lost per decade was <1 among the patients receiving long-term PM therapy. Older age, noncompliance, smoking, bruxism, diabetes, lack of private insurance coverage, maxillary location, furcation involvement, higher mobility, increase in the probing pocket depth and loss of pulpal vitality are strong risk factors for the long-term prognosis of molars.

Mild hyperthermia enhanced synergistic uric acid degradation and multiple ROS elimination for an effective acute gout therapy.

BACKGROUND: Acute gouty is caused by the excessive accumulation of Monosodium Urate (MSU) crystals within various parts of the body, which leads to a deterioration of the local microenvironment. This degradation is marked by elevated levels of uric acid (UA), increased reactive oxygen species (ROS) production, hypoxic conditions, an upsurge in pro-inflammatory mediators, and mitochondrial dysfunction. RESULTS: In this study, we developed a multifunctional nanoparticle of polydopamine-platinum (PDA@Pt) to combat acute gout by leveraging mild hyperthermia to synergistically enhance UA degradation and anti-inflammatory effect. Herein, PDA acts as a foundational template that facilitates the growth of a Pt shell on the surface of its nanospheres, leading to the formation of the PDA@Pt nanomedicine. Within this therapeutic agent, the Pt nanoparticle catalyzes the decomposition of UA and actively breaks down endogenous hydrogen peroxide (H2O2) to produce O2, which helps to alleviate hypoxic conditions. Concurrently, the PDA component possesses exceptional capacity for ROS scavenging. Most significantly, Both PDA and Pt shell exhibit absorption in the Near-Infrared-II (NIR-II) region, which not only endow PDA@Pt with superior photothermal conversion efficiency for effective photothermal therapy (PTT) but also substantially enhances the nanomedicine's capacity for UA degradation, O2 production and ROS scavenging enzymatic activities. This photothermally-enhanced approach effectively facilitates the repair of mitochondrial damage and downregulates the NF-κB signaling pathway to inhibit the expression of pro-inflammatory cytokines. CONCLUSIONS: The multifunctional nanomedicine PDA@Pt exhibits exceptional efficacy in UA reduction and anti-inflammatory effects, presenting a promising potential therapeutic strategy for the management of acute gout.

Design and construction of chemical-biological module clusters for degradation and assimilation of poly(ethylene terephthalate) waste.

The rising accumulation of poly(ethylene terephthalate) (PET) waste presents an urgent ecological challenge, necessitating an efficient and economical treatment technology. Here, we developed chemical-biological module clusters that perform chemical pretreatment, enzymatic degradation, and microbial assimilation for the large-scale treatment of PET waste. This module cluster included (i) a chemical pretreatment that involves incorporating polycaprolactone (PCL) at a weight ratio of 2% (PET:PCL = 98:2) into PET via mechanical blending, which effectively reduces the crystallinity and enhances degradation; (ii) enzymatic degradation using Thermobifida fusca cutinase variant (4Mz), that achieves complete degradation of pretreated PET at 300 g/L PET, with an enzymatic loading of 1 mg protein per gram of PET; and (iii) microbial assimilation, where Rhodococcus jostii RHA1 metabolizes the degradation products, assimilating each monomer at a rate above 90%. A comparative life cycle assessment demonstrated that the carbon emissions from our module clusters (0.25 kg CO2-eq/kg PET) are lower than those from other established approaches. This study pioneers a closed-loop system that seamlessly incorporates pretreatment, degradation, and assimilation processes, thus mitigating the environmental impacts of PET waste and propelling the development of a circular PET economy.

Structural Properties and Surface Modification Decided Pharmacokinetic Behavior and Bio-Distribution of DNA Origami Frameworks in Mice.

This study establishes and validates a series of three dimentional (3D) DNA origami frameworks (DOFs) carrying imaging probes to evaluate their pharmacokinetics and real-time bio-distribution in mice. Three typical DOFs with distinguished structural properties are subjected to mice intravenous injection to systematically investigate their in vivo behaviors. Tracing the radioisotope zirconium-89 (89 Zr) trapped at the inner space of the frameworks, positron emission tomography (PET) imaging is employed to record the real-time bio-distribution of the structures and acquire their pharmacokinetic parameters in the major metabolic organs. The 3D DOFs show different behavior compared to previous structures, with lower kidney accumulation and higher liver retention. Modifications to the structures, such as exposed ssDNA or polyethylene glycol (PEG) moieties, impact their behavior, but are structure-dependent. The 43 nm icosahedra framework among the DOFs perform the best in liver targeting, with the ssDNA extensions enhancing this tendency. The modification of triantennary N-acetylgalactosamine (GalNAc), further improves its uptake in liver cells, especially in hepatocytes over other cell types, discovered by flow cytometry analysis.

The application of composite scaffold materials based on decellularized vascular matrix in tissue engineering: a review.

Decellularized vascular matrix is a natural polymeric biomaterial that comes from arteries or veins which are removed the cellular contents by physical, chemical and enzymatic means, leaving only the cytoskeletal structure and extracellular matrix to achieve cell adhesion, proliferation and differentiation and creating a suitable microenvironment for their growth. In recent years, the decellularized vascular matrix has attracted much attention in the field of tissue repair and regenerative medicine due to its remarkable cytocompatibility, biodegradability and ability to induce tissue regeneration. Firstly, this review introduces its basic properties and preparation methods; then, it focuses on the application and research of composite scaffold materials based on decellularized vascular matrix in vascular tissue engineering in terms of current in vitro and in vivo studies, and briefly outlines its applications in other tissue engineering fields; finally, it looks into the advantages and drawbacks to be overcome in the application of decellularized vascular matrix materials. In conclusion, as a new bioactive material for building engineered tissue and repairing tissue defects, decellularized vascular matrix will be widely applied in prospect.

Effects of polyvinylchloride microplastics on the toxicity of nanoparticles and antibiotics to aerobic granular sludge: Nitrogen removal, microbial community and resistance genes.

Copper oxide nanoparticles (CuO NPs) and ciprofloxacin (CIP) have ecological risk to humans and ecosystems. Polyvinylchloride microplastics (PVC MPs), as a representative of microplastics, may often coexist with CuO NPs and CIP in wastewater treatment systems due to their widespread application. However, the co-impact of PVC MPs in wastewater systems contained with CuO NPs and CIP on nitrogen removal and ecological risk is not clear. In this work, PVC MPs co-impacts on the toxicity of CuO NPs and CIP to aerobic granular sludge (AGS) systems and potential mechanisms were investigated. 10 mg/L PVC MPs co-addition did not significantly affect the nitrogen removal, but it definitely changed the microbial community structure and enhanced the propagation and horizontal transfer of antibiotics resistance genes (ARGs). 100 mg/L PVC MPs co-addition resulted in a raise of CuO NP toxicity to the AGS system, but reduced the co-toxicity of CuO NPs and CIP and ARGs expression. The co-impacts with different PVC MPs concentration influenced Cu2+ concentrations, cell membrane integrity, extracellular polymeric substances (EPS) contents and microbial communities in AGS systems, and lead to a change of nitrogen removal.

Periodontopathic bacterial adhesion to different restorative materials used to elevate proximal subgingival margins.

This study compared the periodontopathic bacterial adhesion to four restorative materials used for deep margin elevation at 2, 24, and 48-h after incubation. Discs were produced from four restorative materials: resin modified glass ionomer, glass hybrid, flowable bulk fill resin composite, and bioactive ionic resin. Root dentin was used as control. Specimens were coated with saliva and used to culture a biofilm comprised of three strains of periodontopathic bacteria; Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans. Bacterial adherence was assessed by colony count assay, crystal violet staining, and visualized using confocal laser scanning microscopy. Data were analyzed by two-way ANOVA followed by Tukey's post hoc tests. The adhesion values for the control specimens were significantly higher than for other materials, while those for the flowable bulk fill were significantly lower than for any other material within all evaluation assays. The 2-h incubation period showed the lowest adhesion values regardless of the group. The 48-h adhesion values were higher than the 24-h results in all groups except the flowable bulk fill. Microscopic imaging partially supported the findings of the measurements. In terms of periodontopathic bacterial adhesion, the tested flowable bulk fill may be preferable for subgingival use over other tested materials.

Ceramic Femoral Heads Exhibit Lower Wear Rates Compared to Cobalt Chrome: A Meta-Analysis.

BACKGROUND: Wear between the femoral head and acetabular liners continues to limit the longevity of total hip arthroplasty implants despite advances in implant materials. The purpose of this meta-analysis was to compare linear wear rates of cobalt-chromium (CoCr) and fourth-generation ceramic femoral heads on highly cross-linked polyethylene (XLPE) liners. METHODS: A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was conducted to identify all studies between 2003 and 2020 that examined in vivo wear rates of either fourth-generation ceramics or CoCr femoral heads on XLPE liners. Studies were analyzed in a weighted means analysis of wear rates and a random effects meta-analysis. RESULTS: A total of 36 studies met inclusion criteria (1,657 CoCr and 659 ceramic patients). The pooled, weighted mean wear rate was 0.063 mm/year (standard deviation [SD]: 0.061, confidence interval [CI]: 0.049-0.077) for CoCr and 0.047 mm/year (SD: 0.057, CI: 0.033-0.062; P < .01) for ceramic (P < .01). A meta-analysis of 4 studies directly comparing ceramic and CoCr found that CoCr heads demonstrated 0.029 mm/year more wear than ceramic heads (95% CI: 0.026-0.059, P = .306). Mean wear for 32-mm heads was significantly higher for ceramic (P < .01), while mean wear for 36-mm heads was significantly higher for CoCr (P < .01). CONCLUSION: Fourth-generation ceramic femoral heads were found to have significantly lower wear rates than CoCr heads. Unlike previous studies, this meta-analysis included only in vivo studies and those with the same generation of highly XLPE liners.

External Z-plasty Technique for Correction of Alar Retraction in Asian Patients.

BACKGROUND: Current strategies for correcting alar retraction mainly include cartilage grafting and composite grafting, which are relatively complicated and may produce injury to the donor site. Herein, we introduce a simple and effective external Z-plasty technique for correcting alar retraction in Asian patients with poor skin malleability. METHODS: Twenty-three patients were presented with alar retraction and poor skin malleability, and they were very concerned about the shape of the nose. These patients undergoing external Z-plasty surgery were analyzed retrospectively. In this surgery, no grafts were needed, and the location of the Z-plasty was according to the highest point of the retracted alar rim. We reviewed the clinical medical notes and photographs. During the postoperative follow-up period, patients' reported satisfaction with aesthetic outcome were also evaluated. RESULTS: The alar retraction of all the patients was successfully corrected. The postoperative mean follow-up period was 8 months (range: 5-28 mo). No incidents of flap loss, recurrence of alar retraction, or nasal obstruction were observed during postoperative follow-up. Within postoperative 3-8 weeks, minor red scarring was visible at the operative incisions in most patients. However, these scars turned unobvious after postoperative 6 months. There were 15 cases (15/23) being very satisfied with the aesthetic outcome of this procedure. Seven patients (7/23) were satisfied with the effect and the invisible scar of this operation. Only one patient was dissatisfied with the scar, but she was satisfied with the correction effect of the retraction. CONCLUSION: This external Z-plasty technique can be an alternative method for correction of alar retraction with no need of cartilage grafting, and the scar can be unobvious with fine surgical suture. However, the indications should be limited in patients with severe alar retraction and poor skin malleability, who should not particularly care about the scars.

An Innovative Stent Consisting of Expanded Polytetrafluoroethylene and Ear Cartilage in Rhinoplasty For Asians: Application I of Dai's Exogenous Extension Stent Concept.

BACKGROUND: Restricted ventilation is common after rhinoplasty with an endogenous extension stent. The authors proposed an exogenous extension stent concept for Asian rhinoplasty patients to avoid this problem. Herein, we introduce an innovative stent in rhinoplasty for Asians, which is an application of this concept. METHODS: An L-shaped expanded polytetrafluoroethylene is hand-carved, and the long arm is placed at the nose back to improve the flatness of the nose, while the short arm supports the nasal column to raise the nose tip. The prosthesis does not occupy nasal volume and therefore theoretically does not affect nasal ventilation. The fan-shaped ear cartilage was placed at the nasal tip to prevent visualization of the nasal tip. The safety and effectiveness of this method were verified through 20 years of clinical practice. The difficulty of learning and popularizing the method was tested through the course of rhinoplasty among 22 plastic surgeons. RESULTS: After 20 years of clinical practice, it was found that this stent could not only effectively improve the nasal dorsum and tip morphology, but also did not actually affect the nasal volume and thus did not affect the nasal ventilation of patients. Among the trainees in plastic surgery, we found that it was not difficult to learn this method of rhinoplasty and the trainees could complete the prosthesis carving well after standardized training. CONCLUSION: This stent consisting of expanded polytetrafluoroethylene and ear cartilage is suitable in rhinoplasty for Asians with significant advantages, one of which is that it has no risk of resulting in restricted nasal ventilation. LEVEL OF EVIDENCE: Level IV.

Impacts of hydraulic conditions on microplastics biofilm development, shear stresses distribution, and microbial community structures in drinking water distribution pipes.

Both microplastic and biofilm are contamination sources in drinking water, but their integrated impacts on water quality have been rarely studied, especially in drinking water distribution pipes with complex hydraulic conditions. This study explored the impacts of hydraulic conditions (0-2 m/s) on microplastic biofilm (MP-BM) development, shear stresses distribution, and microbial community structures. The research was conducted for two weeks using a pilot test device to simulate practical water pipes. The following were the primary conclusions: (1) According to morphology analysis, clusters (>5 µm) significantly increased in the plastisphere when the flow velocity ranged from 0.55 m/s to 0.95 m/s, and average size of clusters decreased when the flow velocity ranged from 1.14 m/s to 1.40 m/s (2) Characteristics of MP-BM impact shear stress on both plastisphere and pipe wall biofilm. Shear stresses were positively correlated with flow velocity, number of MP-BM, and size of MP-BM, while negatively correlated with diameters of pipes. (3) 31 genera changed strictly and monotonously with the fluid velocity, accounting for 15.42%. Opportunistic pathogens in MP-BM such as Sediminibacterium, Curvibacter, and Flavobacterium were more sensitive to hydraulic conditions. Moreover, microplastics (<100 µm) deserve more attention to avoid human ingestion and to prevent mechanical damage and bio-chemical risks.

Dynamic alterations in yak (Bos grunniens) rumen microbiome in response to seasonal variations in diet.

Rumen microorganisms play important roles in the healthy growth of yaks. This study investigated changes in yak rumen microbiome during natural grazing at the warm seasons and supplementary feeding at cold seasons. High-throughput sequencing of 16S rRNA and metagenome analysis were conducted to investigate the structures and functions of yak rumen microbial communities. The results indicated that Bacteroidetes and Firmicutes were the most abundant phyla. In addition, Bacteroidetes might play a more important role than Firmicutes during the supplementary feeding stage (spring and winter), but less during natural grazing stage (summer and autumn). KEGG analysis showed that the amino sugar and nucleotide sugar metabolism, glycolysis/gluconeogenesis, pyruvate metabolism, starch and sucrose metabolism, and fructose and mannose metabolism were the main pathways in the microbial community, which were significantly different between seasons. The carbohydrate-active enzymes (CAZyme) annotation revealed that cellulose was an important carbon source for microorganisms in yak rumen. Glycoside hydrolases (GHs) were the most abundant class of CAZymes, followed by glycosyl transferases (GTs), which were important to digestion of oil, cellulose, and hemicellulose in food. These results contribute to the understanding of microbial components and functions in yak rumen.

3D Ionic Olefin-Linked Conjugated Microporous Polymers for Selective Detection and Removal of TcO4-/ReO4- from Wastewater.

Technetium (99Tc) is a highly toxic radioactive nuclear wastewater contaminant. Real-time detection of 99Tc is very difficult due to its difficult-to-complex nature. Herein, a novel three-dimensional ionic olefin-linked conjugated microporous polymer (TFPM-EP-Br) is constructed using tetrakis(4-aldehyde phenyl)methane (TFPM) as the central monomer. The unique cationic cavity and highly hydrophobic framework enable TFPM-EP-Br to act as a fluorescent sensor for TcO4-. The fluorophores of TFPM-EP-Br can be quenched due to electron transfer from TFPM-EP-Br to TcO4- and the formation of strongly nonfluorescent complexes. Meanwhile, the regular pore channels are beneficial for the fast mass transfer of TcO4-, resulting in an ultrafast response time (less than 2 s) with an ultralow detection limit (33.3 nM). In addition, the ultrahigh specific surface area enables TFPM-EP-Br to combine the ability to synergistically detect and remove radioactive 99Tc. From this perspective, the novel conjugated microporous polymer has made a breakthrough in the detection and extraction of radioactive contaminants.

Alterations in the saliva microbiome in patients with gastritis and small bowel inflammation.

The oral microbiome is an important part of the human microbiome. Accumulating data have shown that oral microbiome alterations are closely related to multiple human diseases. However, salivary microbiota distributions remain unclear in patients with gastritis and small bowel inflammation. Magnetically guided capsule endoscopy (MGCE) is a noninvasive diagnostic tool for patients with gastritis and small bowel inflammation. Herein, we analysed the alterations in saliva microbiota in the normal, small intestinal inflammation and chronic gastritis groups through 16S rRNA gene amplicon sequencing. We found that the abundance of Lactobacillaceae was dramatically higher in chronic gastritis group than healthy individuals (p = 0.001). The levels of Porphyromonas and Faecalibaculum in gastritis samples were increased (p = 0.028; p = 0.006), and the enrichments of Faecalibaculum and Kosakonia in small intestine inflammation samples were elevated (p < 0.001; p = 0.002) compared to those in normal individuals. Our findings clarify the saliva microbiota components and their importance of specific bacteria in gastritis and small bowel inflammation.

Risk factors of reinfection after prosthesis removal and antibiotic bone cement spacer implantation for the treatment of periprosthetic joint infection.

BACKGROUND: Prosthesis removal and antibiotic bone cement spacer implantation is a very important link in two-stage revision of periprosthetic joint infection (PJI) after artificial joint replacement, which is key to the smooth progress of second-stage revision surgery. There are few reports on the risk factors of reinfection after prosthesis removal and antibiotic bone cement spacer implantation for PJI. This study aimed to investigate the risk factors of reinfection after prosthesis removal and antibiotic bone cement spacer implantation for the treatment of PJI. METHODS: Clinical data of 40 patients who underwent prosthesis removal and antibiotic bone cement spacer implantation for PJI after arthroplasty in our hospital from January 2013 to July 2019 were retrospectively analyzed. During the follow-up period of at least 2 years, 21 patients underwent complete two-stage revision after the removal of the antibiotic bone cement spacer, and 19 patients did not receive a new prosthesis due to other factors, such as reinfection or the patient's wishes, record the infection control of patients during the treatment. Reinfection after prosthesis removal and antibiotic bone cement spacer implantation was defined as failure of effective control of infection, symptoms of reinfection, requires increased antibiotic therapy or reoperation. Multivariate Cox proportional hazards model was used to analyze the risk factors associated with reinfection after prosthesis removal and antibiotic bone cement spacer implantation. RESULTS: Of the 40 patients, nine (22.5%) developed reinfection after prosthesis removal and antibiotic bone cement spacer implantation with a mean follow-up duration of 31 months, and multivariate analysis revealed that history of prior revision surgery (hazard ratio [HR] = 6.317, confidence interval [CI]: 1.495-26.700; p = 0.012) and presence of sinus tract before treatment (HR = 5.117, 95% CI: 1.199-21.828; p = 0.027) were independent risk factors for reinfection after prosthesis removal and antibiotic bone cement spacer implantation. CONCLUSION: History of prior revision surgery and presence of sinus tract are two independent risk factors for reinfection in patients with PJI treated with prosthesis removal and antibiotic bone cement spacer implantation.

Reply to: 'comments on 'effects of refractive accommodation on subfoveal choroidal thickness in silicone oil-filled eyes".

In this article, we answered the questions in Lei Gao et al.'s comments on the "effects of refractive accommodation on subfoveal choroidal thickness in silicone oil-filled eyes" one by one.

Effects of refractive accommodation on subfoveal choroidal thickness in silicone oil-filled eyes.

PURPOSE: To investigate the effects of refractive accommodation on subfoveal choroidal thickness (SFCT) in silicone oil (SO)-filled eyes. METHODS: This retrospective, self-comparative study was conducted on 40 patients with unilateral macula-on rhegmatogenous retinal detachment, who underwent vitrectomy and SO tamponade. The SFCT of SO-filled eyes and the fellow control eyes were measured using optical coherence tomography at their one-month visit after surgery. The patients wore soft contact positive lenses for 24 h in the SO-filled eyes, to correct their refractive error. SFCT and choroidal vascularity index (CVI) were measured before and after wearing the contact lenses. Mean SFCT was compared between SO-filled eyes and the fellow control eyes, and SFCT and CVI were compared before and after refractive error correction in the SO-filled eyes. RESULTS: Mean SFCT of SO-filled eyes (221.52 ± 38.41 um) was less than that of the fellow eyes (273.41 ± 31.30 um) (P < 0.001). After refractive error correction, the mean SFCT increased to 269.28 ± 36.90 um(P < 0.001). However, CVI decreased from 57.01 ± 2.41 to 55.39 ± 2.39 (P < 0.05). CONCLUSIONS: SFCT reduction in SO-filled eyes was primarily due to the hyperopia status. The non-uniform change in CVI suggests that changes in CT are mainly attributed to a greater expansion of the stromal area instead of the choroidal vascular area. TRIAL REGISTRATION: This study protocol was reviewed and approved by the Ethics Committee of the Central Theater General Hospital, approval number No. [2020]058-1, retrospectively registered.

In vitro effect of an oral spray and mouthrinses on dual species cariogenic bacteria biofilm.

PURPOSE: To determine the efficacy of an oral spray and oral rinses to inhibit oral cariogenic dual species biofilm formation on hydroxyapatite (HA) discs. METHODS: The Streptococcus mutans (NCTC 10449, ATCC), Lactobacilli casei (NCIB 8820, ATCC) dual species biofilm formation and inhibition on HA disc was tested using five antimicrobial products, i.e., oral spray (Oral Shield), Mouthrinse (Listerine Ultra Clean, Listerine Cool Mint, Crest Pro-Health, ACT Restoring). An untreated group served as control. The established biofilm on the surface of each disc was treated or untreated with oral spray and mouthrinse for 2 minutes after 24 or 48 hours. The dual species biofilm formation and inhibition on HA discs was determined using the spread plate method and colonies were counted and expressed as colony forming units (CFU/mL). Further, the HA disc was subjected to confocal laser scanning microscope (CLSM) examination to determine the viability of cells using live-dead staining and a scanning electron microscope (SEM) to examine the effect on bacteria biofilm and morphology. The cytotoxic effect of test spray and mouthrinse was tested on OKF6/TERT-2 cells using the MTT method. RESULTS: At each time point, 24- or 48-hours, S. mutans and L. casei mixed biofilm on HA discs had a significantly (P> 0.001) fewer number of bacteria in the treated groups than the untreated one. The oral spray and mouthrinses had a detrimental effect on bacteria biofilm, morphology and cell wall, whereas no significant changes were observed in the untreated group. Cytotoxic assay revealed that the oral spray was safe for human oral keratinocyte cells. CLINICAL SIGNIFICANCE: The tested oral spray could offer potential to inhibit the cariogenic bacteria and protect the tooth enamel from cariogenic bacterial biofilm.

High-Quality Conjugated Polymers Achieving Ultra-Trace Detection of Cr2O72- in Agricultural Products.

In view of that conjugated polymers (CPs) are an attractive option for constructing high-sensitive Cr2O72- sensors but suffer from lacking a general design strategy, we first proposed a rational structure design of CPs to tailor their sensing properties while validating the structure-to-performance correlation. Short side chains decorated with N and O atoms as recognition groups were instructed into fluorene to obtain monomers Fmoc-Ala-OH and Fmoc-Thr-OH. Additionally, their polymers P(Fmoc-Ala-OH) and P(Fmoc-Thr-OH) were obtained through electrochemical polymerization. P(Fmoc-Ala-OH) and P(Fmoc-Thr-OH) with high polymerization degrees have an excellent selectivity towards Cr2O72- in comparison to other cations and anions. Additionally, their limit of detection could achieve 1.98 fM and 3.72 fM, respectively. Especially, they could realize the trace detection of Cr2O72- in agricultural products (red bean, black bean, and millet). All these results indicate that short side chains decorated with N and O atoms functionalizing polyfluorene enables the ultra-trace detection of Cr2O72-. Additionally, the design strategy will spark new ideas for the construction of highly selective and sensitive Cr2O72- sensors.