Theoretical and Experimental Study of Different Side Chains on 3,4-Ethylenedioxythiophene and Diketopyrrolopyrrole-Derived Polymers: Towards Organic Transistors.

In this research, two polymers of P1 and P2 based on monomers consisting of thiophene, 3,4-Ethylenedioxythiophene (EDOT) and diketopyrrolopyrrole (DPP) are designed and obtained via Stille coupling polycondensation. The material shows excellent coplanarity and structural regularity due to the fine planarity of DPP itself and the weak non-covalent bonding interactions existing between the three units. Two different lengths of non-conjugated side chains are introduced and this has an effect on the intermolecular chain stacking, causing the film absorption to display different characteristic properties. On the other hand, the difference in the side chains does not have a significant effect on the thermal stability and the energy levels of the frontier orbitals of the materials, which is related to the fact that the materials both feature extremely high conjugation lengths and specific molecular compositions. Microscopic investigations targeting the side chains provide a contribution to the further design of organic semiconductor materials that meet device requirements. Tests based on organic transistors show a slight difference in conductivity between the two polymers, with P2 having better hole mobility than P1. This study highlights the importance of the impact of side chains on device performance, especially in the field of organic electronics.

Graphene Coated Ti-6Al-4V Exhibits Antibacterial and Antifungal Properties Against Oral Pathogens.

PURPOSE: This study aimed to explore the antimicrobial properties of graphene coated Ti-6Al-4V to oral pathogens. MATERIALS AND METHODS: Graphene directly synthesized on Ti-6Al-4V alloy was characterized by scanning electron microscopy (SEM) and Raman spectroscopy. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, live/dead fluorescent staining and SEM were used to analyze the antimicrobial properties of graphene coated Ti-6Al-4V alloy to Porphyromonas gingivalis (P. gingivalis), Fusobacterium nucleatum (F. nucleatum), and Candida albicans (C. albicans). Reactive oxygen species (ROS) generation was monitored to reveal the antimicrobial mechanism. RESULTS: Graphene coated Ti-6Al-4V alloy caused a significant reduction in the presence of both bacterial and fungal pathogens as compared to uncoated Ti-6Al-4V alloy. P. gingivalis, F. nucleatum, and C. albicans on graphene coated Ti-6Al-4V alloy were less active than on uncoated Ti-6Al-4V alloy, and tended to become shrunk and deformed. Meanwhile, graphene coated Ti-6Al-4V alloy induced more generation of ROS in the pathogens than uncoated Ti-6Al-4V alloy. CONCLUSIONS: Graphene coated Ti-6Al-4V alloy exhibited antimicrobial properties against oral pathogens, the induction of oxidative stress might be involved in its antimicrobial mechanisms.

Worldwide prevalence estimates of burning mouth syndrome: A systematic review and meta-analysis.

OBJECTIVES: To evaluate the worldwide prevalence and epidemiology profile of burning mouth syndrome. MATERIAL AND METHODS: A systematic review and meta-analysis was conducted. Search strategies were performed in PubMed, EMBASE, Web of Science, the Cochrane Library, China National Knowledge Infrastructure, and Wanfang database for studies published before January 31, 2021, for the prevalence of burning mouth syndrome. RESULTS: Eighteen articles were included. The overall pooled prevalence of burning mouth syndrome was 1.73% (95% CI = 0.176-0.351, n = 26,632) in general population, and 7.72% (95% CI = 0.434-0.691, n = 86,591) in clinical patients. The subgroup analysis by continent showed that among the population-based studies the prevalence in Asia (1.05%) lower than in Europe (5.58%) and North America (1.10%). The subgroup analysis by gender showed the prevalence of female (1.15%) was higher than male (0.38%) in general population. The subgroup analysis by age showed the prevalence was higher for people over 50 (3.31%) than under 50 (1.92%). CONCLUSIONS: The pooled prevalence of burning mouth syndrome was relatively high in both general population and clinical patients, varies in different regions with the highest prevalence in Europe, and females over 50 years were the most susceptible group. More epidemiological surveys on the prevalence of burning mouth syndrome are needed.

Effectiveness of photobiomodulation in the treatment of primary burning mouth syndrome-a systematic review and meta-analysis.

To evaluate the effectiveness of photobiomodulation (PBM) on primary burning mouth syndrome (pBMS). We searched Chinese and English studies published before February 10, 2020. The databases used include PubMed, EMBASE, the Cochrane Library, Web of Science, Wanfang Database, and China National Knowledge Infrastructure (CNKI). Randomized controlled clinical trials (RCTs) that used the PBM to treat pBMS and reported specific treatment outcomes were considered for inclusion. We eventually included 12 RCTs, and 574 samples were included in these studies. The primary outcomes investigated were pain reduction and life quality improvement. A meta-analysis performed on 9 groups in 5 trials showed that PBM was effective in reducing pain compared with placebo (MD - 1.86, 95% CI - 2.59 to - 1.13, Z = 4.99, P < 0.00001). Meta-analysis was also performed on 7 groups in 4 trials and showed that PBM was effective in improving life quality compared with placebo (MD - 3.43, 95% CI - 5.11 to - 1.75, Z = 4.00, P < 0.0001). Qualitative analysis of the included RCTs found that PBM might also play a role in the decrease of TNF-α and IL-6 in saliva. Three studies that compared PBM with medications were evaluated by descriptive analysis. None of the treatment-related adverse event was reported. Up to date, PBM appears to have an effect on pain reduction and life quality improvement in pBMS patients. However, more evidence is still required to warrant its efficacy and safety in treating pBMS.

Tissue-specific Transcriptome analysis reveals lignocellulose synthesis regulation in elephant grass (Pennisetum purpureum Schum).

BACKGROUND: The characteristics of elephant grass, especially its stem lignocellulose, are of great significance for its quality as feed or other industrial raw materials. However, the research on lignocellulose biosynthesis pathway and key genes is limited because the genome of elephant grass has not been deciphered. RESULTS: In this study, RNA sequencing (RNA-seq) combined with lignocellulose content analysis and cell wall morphology observation using elephant grass stems from different development stages as materials were applied to reveal the genes that regulate the synthesis of cellulose and lignin. A total of 3852 differentially expressed genes (DEGs) were identified in three periods of T1, T2, and T3 through RNA-seq analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of all DEGs showed that the two most abundant metabolic pathways were phenylpropane metabolism, starch and sucrose metabolism, which were closely related to cell wall development, hemicellulose, lignin and cellulose synthesis. Through weighted gene co-expression network analysis (WGCNA) of DEGs, a 'blue' module highly associated with cellulose synthesis and a 'turquoise' module highly correlated with lignin synthesis were exhibited. A total of 43 candidate genes were screened, of which 17 had function annotations in other species. Besides, by analyzing the content of lignocellulose in the stem tissues of elephant grass at different developmental stages and the expression levels of genes such as CesA, PAL, CAD, C4H, COMT, CCoAMT, F5H and CCR, it was found that the content of lignocellulose was related to the expression level of these structural genes. CONCLUSIONS: This study provides a basis for further understanding the molecular mechanisms of cellulose and lignin synthesis pathways of elephant grass, and offers a unique and extensive list of candidate genes for future specialized functional studies which may promote the development of high-quality elephant grass varieties with high cellulose and low lignin content.

Mutation in SSUH2 Causes Autosomal-Dominant Dentin Dysplasia Type I.

Dentin dysplasia type I (DDI) is an autosomal-dominant genetic disorder resulting from dentin defects. The molecular basis of DDI remains unclear. DDI exhibits unique characteristics with phenotypes featuring obliteration of pulp chambers and diminutive root, thus providing a useful model for understanding the genetics of tooth formation. Using a large Chinese family with 14 DDI patients, we mapped the gene locus responsible for DDI to 3p26.1-3p24.3 and further identified a missense mutation, c.353C>A (p.P118Q) in the SSUH2 gene on 3p26.1, which co-segregated with DDI. We showed that SSUH2 (p.P118Q) perturbed the structure and significantly reduced levels of mutant (MT) protein and mRNA compared with wild-type SSUH2. Furthermore, MT P141Q knock-in mice (+/- and -/-) had a unique partial obliteration of the pulp cavity and upregulation or downregulation of six major genes involved in odontogenesis: Dspp, Dmp1, Runx2, Pax9, Bmp2, and Dlx2. The phenotype of missing teeth was determined in zebrafish with morpholino gene knockdowns and rescued by injection of normal human mRNA. Taken together, our observations demonstrate that SSUH2 disrupts dental formation and that this novel gene, together with other odontogenesis genes, is involved in tooth development.

A splicing mutation in VPS4B causes dentin dysplasia I.

BACKGROUND: Dentin dysplasia I (DDI) is a genetically heterogeneous autosomal-dominant disorder characterised by rootless teeth with abnormal pulpal morphology, the aetiology of which presents as genetically heterogeneous. METHODS AND RESULTS: Using a cohort of a large Chinese family with 10 patients with DDI, we mapped to a 9.63 Mb candidate region for DDI on chromosome 18q21.2-q21.33. We then identified a mutation IVS7+46C>G which resulted in a novel donor splice site in intron 7 of the VPS4B gene with co-segregation of all 10 affected individuals in this family. The aberrant transcripts encompassing a new insert of 45 bp in size were detected in gingival cells from affected individuals. Protein structure prediction showed that a 15-amino acid insertion altered the ATP-binding cassette of VPS4B. The mutation resulted in significantly reduced expression of mRNA and protein and altered subcellular localisation of VPS4B, indicating a loss of function of VPS4B. Using human gingival fibroblasts, the VPS4B gene was found to act as an upstream transducer linked to Wnt/ß-catenin signalling and regulating odontogenesis. Furthermore, knockdown of vps4b in zebrafish recapitulated the reduction of tooth size and absence of teeth similar to the tooth phenotype exhibited in DDI index cases, and the zebrafish mutant phenotype could be partially rescued by wild-type human VPS4B mRNA. We also observed that vps4b depletion in the zebrafish negatively regulates the expression of some major genes involved in odontogenesis. CONCLUSIONS: This study identifies VPS4B as a disease-causing gene for DDI, which is one of the important contributors to tooth formation, through the Wnt/ß-catenin signalling pathway.

[Investigation of fibrous cultural materials by infrared spectroscopy].

Cultural fibrous material includes both important categories, i. e. textile and paper, consisting of precious cultural materials in museum, such as costume, painting, and manuscript. In recent years more and more connoisseur and conservator's concerns are, through nondestructive method, the authenticity and the ageing identification of these cultural relics especially made from fragile materials. In this research, we used attenuated total reflection infrared spectroscopy to identify five traditional textile fibers, alongside cotton, linen, wool, mulberry silk and tussah silk, and another five paper fibers alongside straw, wheat straw, long qisong, Chinese alpine rush and mulberry bar, which are commonly used for making Chinese traditional xuan paper. The research result showed that the animal fiber (wool, mulberry silk and tussah silk) and plant fiber (cotton and linen) were easier to be distinguished by comparing the peaks at 3 280 cm-1 belonging to NH stretching vibration and a serious peaks related to amide I to amide III. In the spectrum of wool, the peak at 1 076 cm-1 was assigned to the S-O stretching vibration absorption of cystine in wool structure and can be used to tell wool from silk. The spectrum of mulberry silk and tussah silk seems somewhat difficult to be identified, as well as the spectrum of cotton and linen. Five rural paper fibers all have obvious characteristic peaks at 3 330, 2 900 cm-1 which are related to OH and CH stretching vibration. In the fingerprint wavenumber range of 1 600 - 800 cm, the similar peaks also appeared at 1 370, 1 320 cm-1 and 1 162, 1 050 cm-1, both group peaks respectively are related to CH and CO vibration in the structure of cellulose and hemicellulose in paper fibers. Although there is more similarity of the infrared spectroscopy of these 5 paper fibers, some tiny difference in absorbance also can be found at 3 300 cm-1 and in the fingerprint range at 1 332, 1 203, and 1 050 cm-1 which are related to C-O-C vibration in cellulose. Moreover, in order to explore direct and simple method to identify different materials with similar spectrum,. the principal component analysis (PCA) was applied to separate cotton and linen, mulberry silk and tussah silk, as well as five paper fibers. To eliminate and reduce the spectral scattering caused by sample uneven surface roughness, the multiplicative scatter correction (MSC) has been applied based on total spectral data. The result showed that the score plot using the first two principal components can effectively categorize both group textiles of cotton and linen, as well as mulberry silk and tussah silk, and they have similar chemical structure. For five paper fibers, the PCA was applied in different spectral range (918-550, 1 280-918, 1 700-1 280 and 3 800-2 800 cm-1), and the best result appeared in the range from 3 800 to 2 800 cm-1, in which the five paper fibers can be well categorized. This research showed that infrared spectroscopy combined with principal component analysis has great potential advantage on identifying fibrous materials with similar structure.

A case of complete Melkersson-Rosenthal syndrome: Possibly associated with Mycolicibacterium fortuitum from odontogenic origin.

Melkersson-Rosenthal syndrome (MRS) is a neuromucocutaneous disease of unknown pathogenesis. With this communication, we describe a case of a 26-year-old woman with complete MRS in whom Mycolicibacterium fortuitum was detected in the swelling lip biopsy by next- generation sequencing. The patient's symptoms were slightly improved after intralesional corticosteroid injection combined with broad-spectrum antibiotics, while they were significantly improved after further treatment of dental caries and removal of the residual root. This case provides insight into the possible microbial infection pathogenesis of MRS, and M. fortuitum was speculated to be related to granulomatous and neuronal disorders, most probably from odontogenic origin.

Challenge in the diagnosis, evaluation, and management of burning mouth sensation: A retrospective cohort study.

BACKGROUND: Burning mouth sensation is a common symptom with varying etiologies that can affect patient quality of life. The authors aimed to investigate the clinical characteristics, differentiate the underlying causes, and evaluate the impact on quality of life of patients with burning mouth sensation. CASE DESCRIPTION: A retrospective cohort study of 583 patients with burning mouth sensation symptoms was conducted. Demographic features, clinical characteristics, and associated systemic comorbidities of patients were collected. The 14-item Oral Health Impact Profile Questionnaire score and posttreatment follow-up were evaluated and analyzed among patients. In total, 583 patients with burning mouth sensation symptoms were enrolled; perimenopausal women were most affected; mean (SD) age was 57.04 (12.03) years, and the female to male ratio was 7:1. Patients were stratified into 178 patients (30.53%) with burning mouth syndrome (BMS) and 405 patients (69.47%) without BMS. No significant differences were found for age, sex, clinical characteristics, and 14-item Oral Health Impact Profile Questionnaire scores between BMS and no BMS groups. Notably, 72 of 119 patients without BMS who participated in follow-up had received referrals and treatment for systemic diseases, of which 76.39% achieved complete (45.83%) or partial (30.56%) remission. Among these patients, treatment for gastrointestinal disorders (92.59%), oral candidiasis (78.57%), thyroid diseases (66.67%), and avoidance of local irritants (62.50%) were most effective, and they were perpetuated as the common underlying causes. PRACTICAL IMPLICATIONS: The study results implied significance of adopting multidisciplinary management of burning mouth sensation. It is imperative for dentists and physicians to strengthen their collaborative relationships and focus on both systemic and oral conditions in these patients.

Solution-processed vanadium oxide as a hole collection layer on an ITO electrode for high-performance polymer solar cells.

A solution-processed vanadium oxide (s-VO(x)) anode buffer layer on an indium-tin-oxide (ITO) electrode was used instead of PEDOT:PSS for improving the stability and photovoltaic performance of the polymer solar cells (PSCs). The s-VO(x) layer was prepared by spin-coating a vanadyl acetylacetonate (VO(acac)(2)) isopropyl alcohol solution on the ITO electrode and then thermal annealing at 150 °C for 10 min. The s-VO(x) oxide layer is highly transparent in the visible range and shows effective hole collection property. The photovoltaic performance of the s-VO(x) buffer layer was studied by fabricating the PSCs based on poly(3-hexylthiophene) (P3HT) as an electron donor and four soluble fullerene derivatives, [6,6]-phenyl-C(61)-butyric acid methyl ester (PC(60)BM), [6,6]-phenyl-C(71)-butyric acid methyl ester (PC(70)BM), indene-C(60) bisadduct (IC(60)BA), and indene-C(70) bisadduct (IC(70)BA), as electron acceptors. The PSCs with the s-VO(x) buffer layer show improved performance in comparison with the traditional devices with the PEDOT:PSS buffer layer on ITO, no matter which fullerene derivative was used as an acceptor. The power conversion efficiency of the PSC based on P3HT:IC(70)BA (1 : 1, w/w) with the s-VO(x) anode buffer layer reached 6.35% under the illumination of AM1.5G 100 mW cm(-2).

Chromosome-scale genome assembly provides insights into speciation of allotetraploid and massive biomass accumulation of elephant grass (Pennisetum purpureum Schum.).

Elephant grass (Pennisetum purpureum Schum) is an important forage, biofuels and industrial plant widely distributed in tropical and subtropical areas globally. It is characterized with robust growth and high biomass. We sequenced its allopolyploid genome and assembled 2.07 Gb into A' and B subgenomes of 14 chromosomes with scaffold N50 of 8.47 Mb, yielding a total of 77,139 genes. The allotetraploid speciation occurred approximately 15 Ma after the divergence between Setaria italica and Pennisetum glaucum, according to a phylogenetic analysis of Pennisetum species. Double whole-genome duplication (WGD) and polyploidization events resulted in large-scale gene expansion, especially in the key steps of growth and biomass accumulation. Integrated transcriptome profiling revealed the functional divergence between subgenomes A' and B. A' subgenome mainly contributed to plant growth, development and photosynthesis, whereas the B subgenome was primarily responsible for effective transportation and resistance to stimulation. Some key gene families related to cellulose biosynthesis were expanded and highly expressed in stems, which could explain the high cellulose content in elephant grass. Our findings provide deep insights into genetic evolution of elephant grass and will aid future biological research and breeding, even for other grasses in the family Poaceae.

Preparation and characterization of arginine-modified chitosan/hydroxypropyl methylcellose antibacterial film.

Chitosan and its derivatives are widely used in medical, cosmetic and food fields. In this study, chitosan-N-arginine (CSA) was synthesized and characterized by Fourier-transform infrared (FT-IR), 1H NMR, gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). A novel antibacterial composite film consisting of CSA, hydroxypropyl methylcellose (HPMC) and glycerol was then prepared. The transparent and homogeneous film presented good compatibility between CSA and HPMC, confirmed by SEM. The thickness of the film was about 44.8 µm and its moisture content was 23.0%. Antimicrobial evaluation of CSA/HPMC film showed 9.0 mm bacteriostatic diameter zone against E. coli and 10.5 mm one against S. aureus. The film exhibited cell biocompatibility and promoted proliferation with L929 cell cytotoxicity test. Both antibacterial and cytotoxic results showed that the CSA/HPMC film was a promising material for medication, cosmetics and food preservation applications.

High-performance inverted polymer solar cells with solution-processed titanium chelate as electron-collecting layer on ITO electrode.

High-performance inverted polymer solar cells (PSCs) with solution-processed titanium chelate TIPD as electron collecting layer are reported. The power conversion efficiency (PCE) of the inverted PSC with a-TIPD buffer layer with thermal annealing at 150 °C for 10 min reached 7.4% under the illumination of AM1.5, 100 mW/cm(2), which is increased by 16% in comparison with that (6.4%) of the device in the conventional structure. The PCE of 7.4% is the highest among the inverted PSCs reported so far in the literature.

Structural insights into cellulolytic and chitinolytic enzymes revealing crucial residues of insect ß-N-acetyl-D-hexosaminidase.

The chemical similarity of cellulose and chitin supports the idea that their corresponding hydrolytic enzymes would bind ß-1,4-linked glucose residues in a similar manner. A structural and mutational analysis was performed for the plant cellulolytic enzyme BGlu1 from Oryza sativa and the insect chitinolytic enzyme OfHex1 from Ostrinia furnacalis. Although BGlu1 shows little amino-acid sequence or topological similarity with OfHex1, three residues (Trp(490), Glu(328), Val(327) in OfHex1, and Trp(358), Tyr(131) and Ile(179) in BGlu1) were identified as being conserved in the +1 sugar binding site. OfHex1 Glu(328) together with Trp(490) was confirmed to be necessary for substrate binding. The mutant E328A exhibited a 8-fold increment in K(m) for (GlcNAc)(2) and a 42-fold increment in K(i) for TMG-chitotriomycin. A crystal structure of E328A in complex with TMG-chitotriomycin was resolved at 2.5 Å, revealing the obvious conformational changes of the catalytic residues (Glu(368) and Asp(367)) and the absence of the hydrogen bond between E328A and the C3-OH of the +1 sugar. V327G exhibited the same activity as the wild-type, but acquired the ability to efficiently hydrolyse ß-1,2-linked GlcNAc in contrast to the wild-type. Thus, Glu(328) and Val(327) were identified as important for substrate-binding and as glycosidic-bond determinants. A structure-based sequence alignment confirmed the spatial conservation of these three residues in most plant cellulolytic, insect and bacterial chitinolytic enzymes.