Evaluation of in vitro Streptococcus mutans and Actinomyces naeslundii attachment and growth on restorative materials surfaces.

BACKGROUND: Restorative materials have varying surface characteristics from natural tooth, which may affect oral-bacterial surface attachment/growth. This study examined 48-h Streptococcus mutans (Sm) or Actinomyces naeslundii (An) growth on various restorative materials and tooth surfaces. METHODS: The quantity and viability of 48-hour-old Sm and An growth on polished (180- or 1200-grits), saliva-coated resin composite (RC), glass ionomer cements (GIC), resin-modified GIC (R-GIC), GIC containing casein phosphopeptide-amorphous calcium phosphate (3% (w/w), CPP-ACP GIC), amalgam or tooth blocks (5 × 5 × 1 mm3 ) were examined. RESULTS: Rough-polished (arithmetical mean deviation of the assessed surface roughness profile (Ra): 1.50-1.75 µm) material surfaces revealed relatively higher proportion of inorganic, positively charged surface components ((Si + Al)/C) and greater quantity of surface attached bacteria than smooth polished (Ra: 0.20-0.35 µm) material groups (P < 0.001). Less Sm and An were observed on tooth, and smooth polished GIC and CPP-ACP GIC surfaces than on resin-based materials (RC, R-GIC) and amalgam (P ≤ 0.003). Viability of Sm was found to be lower on amalgam surfaces (P < 0.001), whereas that of An appeared lower on both amalgam surfaces and rough CPP-ACP GIC surfaces (P ≤ 0.033). CONCLUSION: Surface roughness exerted a pronounced effect on in vitro growth/attached Sm/An quantity but may not have an impact on bacteria viability. Interestingly, despite smoother surfaces of various materials tested, fewer Sm/An were observed attaching on tooth surfaces.

IRF4-induced upregulation of lncRNA SOX2-OT promotes cell proliferation and metastasis in cholangiocarcinoma by regulating SOX2 and PI3K/AKT signaling.

OBJECTIVE: The aim of this study was to investigate the role of lncRNA SOX2-OT in the proliferation and metastasis of cholangiocarcinoma (CCA) and its underlying mechanisms. PATIENTS AND METHODS: A total of 82 patients with CCA underwent surgery in our hospital were enrolled in this study. Five CCA cell lines (HuH-28, QBC939, HuCCT1, CCLP1, RBE) were used. The ability of proliferation and metastasis of CCA cells were detected by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, colony formation assay, and transwell assay, respectively. Additionally, in vivo tumor metastasis assay was done. Furthermore, the Kaplan Meier method was used to validate the prognostic importance of SOX2-OT for patients with cholangiocarcinoma. Besides, the protein and mRNA expression of CCA cells were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. RESULTS: The expression level of lncRNA SOX2-OT was significantly upregulated in cholangiocarcinoma tissues. Functional assays were further conducted to prove the oncogenic role of SOX2-OT on the proliferation and metastasis of cholangiocarcinoma cells. Furthermore, mechanism investigations manifested that transcription factor IRF4 upregulates SOX2-OT by promoting the transcriptional activity of SOX2-OT. SOX2-OT could positively regulate the nearby gene SOX2. SOX2-OT suppressed the nuclear transcription of PTEN, thereby activating PI3K/AKT signaling. CONCLUSIONS: lncRNA SOX2-OT upregulated by IRF4 promotes cell proliferation and metastasis in cholangiocarcinoma via upregulating SOX2 and activating PI3K/AKT signaling pathway.

[Research progress on free radicals in human body].

Free radicals are the intermediates of metabolism, widely exist in the human bodies. Under normal circumstances, the free radicals play an important role in the metabolic process on human body, cell signal pathway, gene regulation, induction of cell proliferation and apoptosis, so as to maintain the normal growth and development of human body and to inhibit the growth of bacteria, virus and cancer. However, when organic lesion occurs affected by external factors or when equilibrium of the free radicals is tipped in the human body, the free radicals will respond integratedly with lipids, protein or nucleic acid which may jeopardize the health of human bodies. This paper summarizes the research progress of the free radicals conducted in recent years, in relations to the perspective of the types, origins, test methods of the free radicals and their relationship with human's health. In addition, the possible mechanisms of environmental pollutants (such as polycyclic aromatic hydrocarbons) mediating oxidative stress and free radicals scavenging in the body were also summarized.

Comparative Study of Three Traditional Mongolian Medicines on Streptozotocin-induced Diabetic Nephropathy in Rats.

3 kinds of prescription of Traditional Mongolian (Chinese) Medicine (TMM) have been used in treating diabetic nephropathy (DN). We aimed to investigate: first, which prescription was more effective; second, whether it was more effective when combined with the 3 prescriptions. The DN model was prepared by a single dose of Streptozotocin (STZ, 65 mg/kg, i.p.) in rats and treated 3 times every day with P-1 (Sugmul-10), P-2 (Narenmandul-11), P-3 (Xieriga-4) respectively, and combined group was treated with P-1 in the morning, P-2 and P-3 in the evening. The results showed combining with 3 prescriptions in one day was much more effective than each single prescription. The mechanism of renal protection maybe related to MMP-2 and TGF-ß1, the conclusion could be useful and beneficial for clinical medicine.

Anticonvulsant activity of 2-(substituted-imino)thiazolidin-4-ones.

A novel series of 2-(substituted-imino)thiazolidin-4-ones were synthesized and evaluated for anticonvulsant activity using the maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (Sc-PTZ) assays and their neurotoxicity was measured by the rotarod test. The results of these tests demonstrated that 2-(4-(pentyloxy)phenylimino)thiazolidin-4-one (5d) was the most potent anticonvulsant, with ED50 value of 18.5 mg/kg and 15.3 mg/kg in the MES and Sc-PTZ tests, and protective index (PI=TD50/ED50) values of 10.6 and 12.8 respectively. 5d was much safer than a reference drug Carbamazepine.

Directional differentiation of chicken spermatogonial stem cells in vitro.

BACKGROUND: Mammalian spermatogonial stem cells (SSC) are able to differentiate into different cell types in vitro, which are valuable sources for regenerative medicine and gene transfer studies. We investigated the differentiation potential of chicken SSC into osteoblasts, neuron-like cells and adipocytes in vitro. METHODS: Chicken SSC from the testes of 18- and 20-day-old chicken embryos were cultured in different induction media for three passages in vitro. For differentiation into osteoblasts, SSC were cultured in Dulbecco's modified Eagle medium (DMEM) supplemented with 1 x 10(-4) micromol/mL desamethasone, 10 micromol/mL (beta-sodium glycerophosphate and 0.05 mg/mL vitamin C, and examined by microscopy after Von Kossa's, cytochemical and immunohistochemical staining. For differentiation into neuron-like cells, SSC were cultured in DMEM supplemented with 1 x 10(-3) micromol/mL retinoic acid (RA), 5.0 micromol/mL 3-isobutyl-1-methylxanthine (IBMX) and examined by microscopy after toluidine blue or immunohistochemical staining. For differentiation into adipocytes, SSC were cultured in DMEM supplemented with 1 x 10(-3) micromol/mL dexamethasone, 0.01 mg/mL insulin, 0.5 micromol/mL IBMX and examined by microscopy after Oil red O staining and reverse transcriptase-polymerase chain reaction (RT-PCR) for gene expression of peroxisome proliferation activation receptor-gamma (PPAR-gamma). RESULTS: After 15 and 21 days of culture in the induction medium for osteoblast differentiation, 75% and 80% chicken SSC differentiated into osteoblasts, as confirmed by Von Kossa's, calcium-cobalt and collagen I antibody staining. After 3 and 7 days of culture in the induction medium for neuron-like cell differentiation, 78% and 85% SSC became neuron-like cells, as confirmed by staining with toluidine blue and the monoclonal antibody against neuron-specific enolase, nestin and glial fibrillary acidic protein. After 7 days of culture in the induction for adipocyte differentiation, 85% SSC differentiated into adipocytes, as confirmed by Oil red O staining and RT-PCT for PPAR-gamma gene expression. DISCUSSION: Our results show that chicken SSC can differentiate into osteoblasts, neuron-like cells and adipocytes under similar conditions as for directional differentiation of mammalian SSC in vitro. The findings show the feasibility of using SSC-derived cells for developmental biology and gene transfer studies in chickens.