Effect of ALA-PDT on inhibition of oral precancerous cell growth and its related mechanisms.

BACKROUND: Early treatment of oral precancerous lesions is considered as a key strategy for in oral carcinogenesis prevention. Increasing evidence has suggested that the transforming growth factor beta (TGF-ß) signaling pathway is tightly involved in the process of oral-carcinogenesis. In this study, we investigated the inhibition effect and potential mechanism of 5-aminolaevulinic acid photodynamic therapy (ALA-PDT) in human oral precancerous cells via TGF-ß pathway. MATERIALS AND METHODS: Here, the dysplastic oral keratinocyte (DOK) cells were incubated with ALA concentration of 1 mM/mL for 4 h and then irradiated with a Helium-Neon (He-Ne) ion laser at 633 nm (200 mW/cm2). The control cells were cultured in Dulbecco's modified Eagle's medium (DMEM) medium. We analyzed the differentially expressed genes and correlated pathways in oral precancerous cells following ALA-PDT using Affymetrix microarrays. TGF-ß pathway was analyzed by quantitative real-time polymerase chain reaction (RT-qPCR) and western blotting. Bioinformatics analysis was performed to evaluate the expression of TGF-ß1 in human oral cancer samples and adjacent normal samples. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), flow cytometry, 2'-7'-dichlorodihydrofluorescein diacetate (DCFH-DA), and wound healing assay were used to assess the effects of ALA-PDT plus TGF-ß receptor inhibitor (LY2109761) in DOK cells. RESULTS: The TGF-ß signaling could exert in suppressive effects on DOK cells after ALA-PDT. The cell proliferation and migration rate of DOK cells was significantly reduced and apoptosis and ROS generation induced more effectively by ALA-PDT combined with LY2109761. Furthermore, cell cycle analysis revealed that the combined treatment resulted in G0/G1 phase arrest. CONCLUSIONS: ALA-PDT suppresses the growth of oral precancerous cells by regulating the TGF-ß signaling pathway, and its suppressive effect was enhanced using LY2109761. These results indicate that it could be a promising alternative treatment against oral precancerous lesions.

Microbial community alteration in tongue squamous cell carcinoma.

Tongue squamous cell carcinoma (TSCC) is the most common oral cavity malignancy. The role of the microbial community in TSCC development and progression is unclear. In the present study, 23 patients with TSCC were recruited. Tissue DNA was extracted from cancer and paracancerous normal tissues from all participants. Next-generation 16S rDNA amplicon sequencing and functional prediction were applied for taxonomic analysis. Alpha diversity measurements using the Shannon and Simpson diversity indexes indicated a significant increase in the microbiotic diversity of cancer samples (Shannon index: P = 0.001, Simpson index: P = 0.015); otherwise, no differences were found when using observed operational taxonomic units (OTUs) and Chao1 index (observed OTUs: P = 0.261, Chao1 index: P = 0.054). The dominant phyla of the microbiota included Bacteroidetes, Proteobacteria, Firmicutes, Actinobacteria, and Fusobacteria. Multivariate analysis of variance (Adonis) and nonparametric analysis of similarities (ANOSIM) based on unweighted unifrac distances demonstrated differences in the bacterial community structure between the two groups (P = 0.001 for Adonis, P = 0.001 for ANOSIM). Compared with the normal samples, Neisseria, Streptococcus, and Actinomyces levels decreased significantly in cancer samples. Co-occurrence network analysis implied that the bacterial community in cancer was more conserved than that in normal tissue. Matched-pair analysis of cancer and control samples revealed a significant alteration in the relative abundance of specific taxa. These findings will enrich our knowledge of the association between the oral microbial community and TSCC. Further experiments should investigate the potential carcinogenic mechanism of microbial community alterations in TSCC. KEY POINTS: • Microbial community role in tongue squamous cell carcinoma. • Significant alteration of microbiome found between cancer and normal tissues. • Microbial community alteration and potential carcinogenic mechanism.

The Role of Autologous Platelet Concentrates in the Treatment of Medication-Related Osteonecrosis of the Jaw.

ABSTRACT: The frequent refractory response of patients to the treatment of medication-related osteonecrosis of the jaw (MRJON) has attracted clinicians' attention to several treatments. However, they are at best, palliative, and have a higher failure rate than previous treatments. The present meta-analysis was performed to evaluate the clinical effectiveness of autologous platelet concentrates (APCs) combined with surgery in the treatment of MRONJ. The authors conducted a meta-analysis involving a systematic search of PubMed, EMBASE, Wiley Online Library and the Cochrane Library for eligible studies from their inception to November 2019, in accordance with preselected criteria. The inverse variance method was applied to fixed or random effects models based on the heterogeneity of the studies. Thirteen studies that investigated APCs in the treatment of MRONJ were eligible for inclusion in the meta-analysis of 223 patients and 33 lesions. The pooled success rate of APCs combined with surgery for MRONJ was 90% (95%CI, 80%-97%) and the pooled OR was 7.67 (95%CI, 2.10-27.98), indicating the combination was 7.67 times more effective than surgery alone. The results suggest that the use of APCs is a promising therapeutic regimen, as it provided additional benefits to surgery in the treatment of MRONJ. To achieve the benefits, a tension-free primary closure of the soft tissue is recommended as well. Randomized studies with large sample sizes is warranted to confirm our finding.

[Phonetic parameters analysis of articulated consonant with different denture base].

OBJECTIVE: To compare the phonetic parameters changes of titanium denture base materials to that of conventionally processed poly methyl methacrylate (PMMA) resin. METHODS: Forty-two edentulous patients were included in this study. Each patient received two sets of dentures. One of the upper denture was restored with titanium denture base, the other was restored with conventional PMMA denture base. Consonant /x, sh, r, zh, ch, j, q/ associated with place of articulation and manner of articulation were chosen and all of the processed acoustic specimens were stored at computerized speech lab (CSL). Model 4150 (KAY) for the first concentrated frequency area (CFA-1), voice onset time (VOT) and spectrogram were analyzed. RESULTS: The consonant articulation effect of denture base showed significant difference between the two type of dentures in the CSL. The consonant parameters (/x, sh, r, zh, ch, j, q/) CFA-1 of group A [(3595 +/- 102), (3089 +/- 104), (1876 +/- 116), (4078 +/- 116), (3604 +/- 119), (5432 +/- 118), (4934 +/- 121) Hz] was different from the one of group B [(3644 +/- 101), (3280 +/- 88), (1978 +/- 113), (4214 +/- 193), (3817 +/- 49), (5478 +/- 158), (5020 +/- 183) Hz] (P < 0.05). The consonant parameters VOT of /zh, ch, j/ in group A [(54.67 +/- 1.13), (143.80 +/- 2.24), (62.53 +/- 0.75) ms] was different from those of group B [(52.88 +/- 0.34), (137.55 +/- 2.50), (62.00 +/- 1.54) ms] (P < 0.05). The consonant parameters VOT of /g, k/ in group A [(26.94 +/- 0.33), (114.53 +/- 2.15) ms] was different from those of group B [(28.59 +/- 0.65), (124.40 +/- 3.74) ms] (P < 0.05). A redundant spike as it was located prior to the inherent spike could be observed in the /g, k/ spectrogram of the PMMA denture base group. CONCLUSIONS: Titanium denture base is recommended to provide a satisfying form of articulate position with thinner front palate thickness of the denture base. CFA-1 and VOT based CSL are effective acoustic parameters for articulation testing after denture delivery.

Fracture strength of custom-fabricated Celay all-ceramic post and core restored endodontically treated teeth.

BACKGROUND: The increased use of all-ceramic crown provides a rationale for tooth-colored core. Due to superior mechanical properties, Vita Celay infiltration ceramic developed for crown and bridge works presents the potential for fabricating all-ceramic posts and cores in one piece. This study was conducted to compare the fracture strength of endodontically treated teeth which were thereafter given different types of posts and cores and crowns restoration, respectively. The evaluated post-and-core systems are: custom-fabricated Celay all-ceramic post-core, custom cast metal post-core, and prefabricated stainless steel post (Parapost) with and without 2.0 mm dentine ferrule. METHODS: Sixty freshly extracted human maxillary central incisors were endodontically treated and randomly divided into five groups with 12 samples each. Group A: Celay ceramic post-cores restored teeth with 2.0 mm dentine ferrule. Group B: Celay ceramic post-cores restored teeth with no dentine ferrule. Group C: cast metal post-cores restored teeth with 2.0 mm dentine ferrule. Group D: cast metal post-cores restored teeth with no dentine ferrule. Group E: prefabricated post and composite cores restored teeth with 2.0 mm dentine ferrule. All teeth were restored with Celay ceramic crowns. Each specimen was subjected to a load at a 45-degree angle to the long axis on MTS 810 material testing machine until failure, at crosshead speed of 0.02 cm/minute. Analysis of variance followed by the Newman-Keuls pairwise multiple comparison tests were used to compare the results of the groups tested. RESULTS: There was a statistically significant difference among the five groups (P < 0.01). Celay ceramic post-cores restored teeth with 2.0 mm dentine ferrule [(758.35+/-19.26) N] and cast metal post-cores restored teeth with 2.0 mm dentine ferrule [(756.63+/-66.22) N] had a significantly greater mean fracture strength than the other three groups in which no significant difference was observed. The 2.0 mm dentine ferrule could cause significant fracture resistance alteration of Celay post-core restored teeth. CONCLUSIONS: When covered with Celay ceramic crowns, Celay post-cores restored teeth with 2.0 mm dentine ferrule and cast metal post-cores restored teeth with 2.0 mm dentine ferrule have similar fracture strength. There was a statistically significant difference between the fracture resistance of Celay post-core restored teeth with and without 2.0 mm dentine ferrule.

[Cloning and expression of the succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum Chinese strain in E. coli].

OBJECTIVE: To clone the full-length gene encoding succinate dehydrogenase iron-sulfur protein of Schistosoma japonicum (SjSDISP) Chinese strain and express it in Escherichia coli. METHODS: According to the published incomplete EST (BU804141) of SjSDISP and the sequence of multiclone sites of lambda gt11 vector, 2 pairs of primers were designed and synthesized. Then the 3' and 5'ends of the EST of the SjSDISP from adult Schistosoma japonicum cDNA library were amplified by anchored PCR. After sequencing, a full-length cDNA sequence of the SjSDISP was obtained, and then it was cloned into prokaryotic expression vector pGEX-4T-1. Identified by agarosed gel electrophoresis, endonucleases digestion and PCR, the resultant recombinant plasmid was used for the expression under the temperature-dependent condition and Western blot analysis. RESULTS: A 1,071 bp sequence was obtained. Sequence analysis showed that the fragment contained a complete open reading frame (ORF), encoding 278 amino acid residues. This target fragment was cloned into the prokaryotic expression vector pGEX-4T-1, and expressed in Escherichia coli. SDS-PAGE revealed that the molecular weight of the expressed fusion recombinant product was 56 kD. Western blot showed that the recombinant protein was recognized by polyclonal rabbit antiserum immunized with Schistosoma japonicum adult worm antigen. CONCLUSION: Cloning of the full-length gene encoding SjSDISP and its bacterial expression were successfully done.

Development of a vaccine against Schistosoma japonicum in China: a review.

Significant progress has been made over the past 50 years in the control of schistosomiasis japonica in China. However, recent data suggest that the disease is re-emerging. By the end of 2003, Schistosoma japonicum was still endemic in 110 counties in seven provinces in the southern part of China where the long-term reduction of the disease has been replaced by an increase in the number of people infected and areas infested by the intermediate host snail, i.e. Oncomelania hupensis. Explanations are multifactorial, including the construction of the Three Gorges dam, major flooding events, recovery of the Dongting Lake and the possible impact of climate change. An efficacious vaccine against S. japonicum would represent a significant addition to the current arsenal of control tools, particularly in the framework of an integrated control approach. The vaccine could be targeted either towards the prevention of infection or towards the reduction of parasite fecundity. Although progress in this field has been relatively slow, encouraging results have been obtained in recent years using defined native and recombinantly derived S. japonicum antigens. These findings suggest that development of a safe and efficacious vaccine is feasible. This paper reviews the progress in the development of a vaccine against S. japonicum in China, and includes also data from foreign researchers who are engaged in collaborative work with Chinese scientists.