Gastroprotective effects of Machilus zuihoensis Hayata bark against acidic ethanol-induced gastric ulcer in mice

Background and aim

In traditional medicine, Machilus zuihoensis Hayata bark (MZ) is used in combination with other medicines to treat gastric cancer, gastric ulcer (GU), and liver and cardiovascular diseases. This study aims to evaluate the gastroprotective effects and possible mechanism(s) of MZ powder against acidic ethanol (AE)-induced GU and its toxicity in mice.

Experimental procedure

The gastroprotective effect of MZ powder was analyzed by orally administering MZ for 14 consecutive days before AE-inducing GU. Ulcer index (UI) and protection percentage were calculated, hematoxylin and eosin staining and periodic acid-Schiff staining were performed, and gastric mucus weights were measured. The antioxidative, anti-inflammatory, and anti-apoptotic mechanisms, and possible signaling pathway(s) were studied.

Results and conclusion

Pretreatment with MZ (100 and 200 mg/kg) significantly decreased 10 μL/g AE-induced mucosal hemorrhage, edema, inflammation, and UI, resulted in protection percentages of 88.9% and 93.4%, respectively. MZ pretreatment reduced AE-induced oxidative stress by decreasing malondialdehyde level and restoring superoxide dismutase activity. MZ pretreatment demonstrated anti-inflammatory effects by reducing both serum and gastric tumor necrosis factor-α, interleukin (IL)-6, and IL-1β levels. Furthermore, MZ pretreatment exhibited anti-apoptotic effect by decreasing Bcl-2 associated X protein/B-cell lymphoma 2 ratio. The gastroprotective mechanisms of MZ involved inactivations of nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) and mitogen activated protein kinase (MAPK) signaling pathways. Otherwise, 200 mg/kg MZ didn't induce liver or kidney toxicity. In conclusion, MZ protects AE-induced GU through mucus secreting, antioxidative, anti-inflammatory, and anti-apoptotic mechanisms, and inhibitions of NF-κB and MAPK signaling pathways.

[Application of periodontal regeneration strategy by treating both symptoms and primary cause in natural tooth preservation]

Teeth with severe periodontitis always have occlusal trauma, local anatomical abnormalities, mucogingival deformities or other factors that aggravate plaque retention or periodontal tissue damage. For these teeth, the author put forward the strategy of treating both symptoms and primary cause. That is, carrying out the periodontal regeneration surgery on the basis of analyzing and removing the primary cause factors. Through literature review and case series analysis, this paper discusses the therapeutic effects of strategy by treating both symptoms and primary cause on teeth with severe periodontitis, in order to provide reference for clinician work.

Study of pharyngeal airway morphology with CBCT: Benefits of four premolar extraction orthodontic treatments

BACKGROUND AND AIM

Four premolars extractions are routine procedures for correction of malocclusion, but will inevitably lead to a reduction of tongue space, whether this will weaken the pharyngeal airway remains a controversy.

PATIENTS AND METHODS

Cone-beam computed tomography (CBCT) radiographs of 80 patients who completed four premolar extraction orthodontic treatments were collected and divided into three anteroposterior skeletal groups according to the ANB (angle subspinale to nasion to supramentale) value. Linear, angular, cross-sectional area, and volumetric dimensions of the pharyngeal airway were measured using Dolphin Imaging 11.9 software. One-way analysis of variance and Pearson's correlation coefficient test were performed to assess the intergroup comparisons. Treatment changes were evaluated with two-sample t-tests.

RESULTS

In intergroup comparisons, vertical linear and cross-sectional area differences were identified in S-Go/N-Me, VD1, VD1/N-Me, VD2/N-Me, AA, OAA and OMINI (p<0.05), while other measurements showed no significant differences. Angle2, the tilting degree of the pharyngeal airway, showed a positive correlation with ANB (p<0.05). As for the treatment changes, a significant increase was found in the pharyngeal airway in the Class I group (OUA p<0.05, VD1 p<0.001, VD2 p<0.05) and Class II group (VD1 p<0.001. VD2, p<0.05), and inversely, a significant decrease was found in the pharyngeal airway in the Class III group (OAA p<0.05, OMINI p<0.05, OUA p<0.05). No volumetric difference was identified. Interestingly, regarding the preoperative pharyngeal airway size, values trended to the mean value significantly.

CONCLUSION

Four premolar extraction orthodontic treatments did not affect the pharyngeal airway volume except for the vertical liner and cross-sectional area dimensions. The trend of the gold standard suggested a positive influence of four premolar extraction orthodontic treatments.

Pyrolysis gas from biomass and plastics over X-Mo@MgO (X = Ni, Fe, Co) catalysts into functional carbon nanocomposite: Gas reforming reaction and proper process mechanisms

The metal catalysts X-Mo@MgO (X = Ni, Fe, Co) was studied as excellent catalyst for catalytic pyrolysis conversion of biomass and plastics into functional carbon nanocomposite. The proper reaction mechanism of the process was explored through the gas composition, and explored the bactericidal performance of functional carbon nanocomposite. The results showed that the Ni, Fe and Co-based catalysts elevated H₂ gas yield reached to 57%, 34% and 44% as the addition of Mo, due to Mo or its oxide species for scission of small molecule compound. The introduction of NiMo@MgO catalyst produced lower CH₄, and higher H₂ and MWCNTs, which indicated that the formation of MWCNTs is mainly attributed to CH₄ dehydrogenation. As a comparison, FeMo@MgO catalyst for CO disproportionation reaction could generate more MWCNTs and lower H₂. The functional carbon nanocomposite from FeMo@MgO catalyst were comprehensively evaluated by multiple characterizations. TPO and Raman results confirmed that FeMo@MgO catalyst can provide an excellent carrier to generate MWCNTs with few defects and high graphitization. The functional carbon nanocomposite were initially applied to E.coli extinguishing. The core-shell structure catalyst not only has excellent bactericidal performance, but also has strong resistance to metal leaching.

Calculating and modeling the exchange energies of homonuclear and heteronuclear alkali dimers based on the surface integral method

The exchange energies of all homonuclear and heteronuclear alkali dimers are calculated based on the surface integral method. These results are generally in good agreement with both ab initio calculations and experimental results where available. It is also shown that the exchange energies could be fitted by an analytical expression of AR(b) exp(-cR). b and c can be calculated by two simple formulas that are only related to the ionization energies of the constituent atoms. A is the only parameter in this expression. More interestingly, it is found that the parameter A for the heteronuclear dimers could be approximated by a combining rule.

The effect of enamel matrix derivative (Emdogain®) on gene expression profiles of human primary alveolar bone cells

Emdogain® is frequently used in regenerative periodontal treatment. Understanding its effect on gene expression of bone cells would enable new products and pathways promoting bone formation to be established. The aim of the study was to analyse the effect of Emdogain® on expression profiles of human-derived bone cells with the help of the micro-array, and subsequent validation. Bone was harvested from non-smoking patients during dental implant surgery. After outgrowth, cells were cultured until subconfluence, treated for 24 h with either Emdogain® (100 µg/ml) or control medium, and subsequently RNA was isolated and micro-array was performed. The most important genes demonstrated by micro-array data were confirmed by qPCR and ELISA tests. Emdogain tipped the balance between genes expressed for bone formation and bone resorption towards a more anabolic effect, by interaction of the PGE2 pathway and inhibition of IL-7 production. In addition the results of the present study indicate that Emdogain possibly has an effect on gene expression for extracellular matrix formation of human bone cells, in particular on bone matrix formation and on proliferation and differentiation. With the micro-array and the subsequent validation, the genes possibly involved in Emdogain action on bone cells were identified. These results can contribute to establishing new products and pathways promoting bone formation.

High Dielectric Hyperbranched Polyaniline Materials

New organic materials for the purpose of high speed capacitor applications are discussed. The effect of the microcrystalline size dependence of different polyaniline polymeric systems on the dielectric constant is investigated. Two different methods are described for the preparation of the polyaniline dielectric materials. By sonication polymerization, the prepared polyaniline with a suggested hyperbranched structure showed much larger microcrystalline domains in comparison to the conventional linear polyaniline. Investigations of the dielectric constant and capacitance at a relatively high frequency (>100 kHz) suggested that the system with the larger microcrystalline domains (hyperbranched) gives rise to a larger dielectric constant. The mechanism of the increased dielectric response at higher frequencies is investigated by EPR spectroscopy, and these results suggest that delocalized polarons may provide a way to enhance the dielectric response at high frequency.

Polaron Delocalization in Ladder Macromolecular Systems

Organic macromolecules with conjugated building blocks have been the focus of extensive research that is motivated, in part, by the potential to create optical and electronic devices. We have shown that palladium-catalyzed amination can assemble triarylamine ladder materials with extended structures. Two ladder macromolecules have been prepared in high yields by a series of twelve or sixteen C-N coupling reactions. Studies of the electronic and optical properties of neutral and oxidized forms of the ladder structures were conducted. The optical and electronic properties of the ladder systems are compared to those of the linear tetra-phenyl-p-phenylenediamine as well as the tetra-p-anisyl-p-tetraazacyclophane. The electrochemistry of the ladder systems consists of a multiwave voltammogram with a relatively low first oxidation potential. Electron paramagnetic resonance spectroscopy of the ladder systems suggests the presence of a large density of delocalized polarons. Linear absorption measurements of the chemically oxidized ladders revealed both polaron and intervalence absorption bands. Steady-state and time-resolved fluorescence measurements were also carried out to characterize the dynamics in these novel systems.

Beta-amyloid peptide fragment 31-35 induces apoptosis in cultured cortical neurons

A synthetic fragment 31-35 of beta-amyloid peptide was used in cultured cortical neurons to examine whether this smaller sequence could trigger apoptotic degeneration in vitro by using morphological, biochemical and flow-cytometric examinations. The results showed that: (i) neurons treated with fragment 31-35 of beta-amyloid peptide exhibited membrane blebbing, compaction of nuclear chromatin, nuclear shrinkage and nuclear fragmentation; (ii) a typical DNA ladder was revealed by agarose gel electrophoresis following fragment 31-35 of beta-amyloid peptide exposure; (iii) the internucleosome DNA fragmentation was also detected by flow-cytometric examination following fragment 31-35 of beta-amyloid peptide exposure; and (iv) the DNA fragmentation induced by fragment 31-35 of beta-amyloid peptide in the above two examinations could be blocked by co-treatment with aurintricarboxylic acid or actinomycin D. It is suggested that fragment 31-35 of the beta-amyloid peptide may be a shorter sequence of beta-amyloid peptide responsible for triggering an apoptotic process in cultured neurons.