ABSTRACT
Studies have shown that autoimmune disease (AID)-related ulcers are disease complications that lead to serious poor prognosis such as infection and disability. It is difficult to make a clear diagnosis and there are contradictions between the applications of immunosuppressive therapy and anti-infectious therapy. Improper diagnosis and immunosuppressive therapy can easily delay the timing of anti-infectious therapy and surgery for patients, which bring adverse effects on the prognosis of patients. This paper reviews the concept, clinical characteristics and treatment suggestions of each subtype of AID-related ulcers, in order to provide more ideas for AID-related ulcers' clinical diagnosis and treatment.
Subject(s)
Humans , Autoimmune Diseases/therapy , Ulcer/complicationsABSTRACT
Objective To analyze the epidemiological characteristics of COVID-19 cases reported in Xianyang City from January to February 2020. Methods We retrospectively studied 17 COVID-19 patients diagnosed in Xianyang Central Hospital. The patients were characterized clinically and epidemiologically. Results The 17 patients included 10 male and 7 female, with an average age of(39.59±17.31)years. The median interval of time between onset and diagnosis was four days(1-10 days), whereas the median duration of COVID-19 was 16 days(3-23 days). Of the patients, six were mild, 10 were pneumonia, and one was severe. A total of 15 patients had fever as the onset, accompanied by fatigue, sore throat, sputum, vomit, muscle soreness; the other two patients were asymptomatic. There were no complications documented in all the patients. Patients had low levels of white blood cells and lymphocytes. Chest CT scan showed diverse diffuse ground-glass shadow. Eleven patients had travel history in Wuhan before the onset, four patients had contact with people who had travel history or residence history in Wuhan, and the other two patients did not report epidemiological exposure history. In addition, four of the 17 patients were clustered cases. Conclusion General population is susceptible to COVID-19. The majority of the confirmed cases have epidemiological exposure history. Routine examination, including white blood cell, lymphocyte count and CT scan may facilitate early diagnosis.
ABSTRACT
Objective:To apply 13N-ammonia PET/CT cerebral blood perfusion imaging combined with methazolamide challenge for cerebrovascular reserve (CVR) evaluation in ischemic cerebrovascular diseases. Methods:From January, 2014 to December, 2016, 56 ischemic stroke patients with serious stenosis of unilateral internal carotid artery or middle cerebral artery accepted basal and stress PET/CT with methazolamide challenge. The patients were divided into normal-CVR group (n = 29) and reduced-CVR group (n = 27) according to the results of CVR, and followed up for 24 months. The ischemic cerebrovascular events and cerebral blood flow were observed. Results:The incidence of transient ischemic attack was more in the reduced-CVR group than in the normal-CVR group (χ2 = 4.389, P < 0.05), while the incidence of ischemic stroke increased a little with no significant difference between the two groups (P > 0.05). The CBF was improved in normal-CVR group after treatment (t = 2.409, P < 0.05), and the improvement was not significant in reduced-CVR group (t = 0.648, P > 0.05). Conclusion:13N-ammonia PET/CT cerebral blood flow perfusion imaging combined with methazolamide challenge can be used to evaluate CVR to predict the outcome for patients with cerebral ischemic disease, which is helpful for early intervention.
ABSTRACT
Objective:To detect the colony number of bacteria, yeasts and molds in fermentation process of Pinelliae Rhizoma Fermentata (PRF), microbial flora species, and quantitatively analyze the dynamic changes of four dominant microorganisms at different fermentation time points of PRF, so as to provide experimental basis for exploring the processing mechanism of PRF. Method:According to Pharmaceutical Standard Preparation of Traditional Chinese Medicine Prescription of Ministry of Health of the People's Republic of China (the 10th volume), PRF was processed. The samples at five different fermentation time points (0, 30, 60, 90, 120 h) of PRF were taken, the culturing, isolation and purification of bacteria, yeasts and molds were carried out with selective media, and the colonies were counted. Fluorescence quantitative polymerase chain reaction (PCR) technique was employed to conduct absolute quantification of Bacillus subtilis, Paecilomyces variotii, Byssochlamys spectabilis and Aspergillus niger. The recombinant plasmids of these 4 microorganisms were used as the standard substances, and the standard curves were prepared after dilution of multiple ratios, quantitative analysis was performed on these 4 microorganisms in five samples at different processing time points (0, 30, 60, 90, 120 h) of PRF. Result:During the fermentation process of PRF, the number of bacteria was low with smooth change, while molds and yeasts grew dramatically at the late stage of fermentation and reached 1×106 CFU·mL-1 at the end of fermentation. At 5 different fermentation time points, the copy numbers of Bacillus subtilis were 3.53×105, 7.56×104, 1.58×105, 1.90×106, 1.85×106 copies·g-1, the copy numbers of Paecilomyces variotii were 0, 0, 0, 3.45×107, 4.15×108 copies·g-1, the copy numbers of Byssochlamys spectabilis were 0, 0, 0, 1.04×108, 2.28×108 copies·g-1, the copy numbers of Aspergillus niger were 0, 0, 9.48×105, 1.47×106, 7.56×106 copies·g-1, respectively. Conclusion:The change trend of microflora in the fermentation process of PRF can be reflected by the dynamic change of four dominant microorganisms, and molds may play an important role in the processing of PRF. Fluorescence quantitative PCR technique has the advantages of rapidity, sensitivity, good repeatability and high specificity, it is suitable for exploring processing mechanism of PRF.
ABSTRACT
A high-content GABA was found in Sojae Semen Praeparatum(SSP), which is a famous traditional Chinese medicine and officially listed in Chinese Pharmacopoeia. To screen out and identify GABA-producing microbes from samples at different time points during the fermenting process of SSP, traditional microbiological methods combined with molecular biological methods were used to study the predominant GABA-producing microorganisms existing in the fermenting process of SSP. This study would lay a foundation for further studying the processing mechanism of SSP. The fermenting process of SSP was based on Chinese Pharmacopoeia(2010 edition), and samples were taken at different time points during the fermenting process of SSP. The bacteria and fungi from samples at different time points in the fermenting process of SSP were cultured, isolated and purified by selective medium, and dominant strains were selected. The dominant bacteria were cultured in the designated liquid medium to prepare the fermentation broths, and GABA in the fermentation broth was qualitatively screened out by thin-layer chromatography. The microbial fermentation broth with GABA spots in the primary screening was quantitatively detected by online pre-column derivatization and high performance liquid chromatography established in our laboratory. GABA-producing microorganisms were screened out from predominant strains, and their GABA contents in fermentation broth were determined. The DNA sequences of GABA-producing bacteria and fungi were amplified using 16S rDNA and 18S rDNA sequences by PCR respectively. The amplified products were sequenced, and the sequencing results were identified through NCBI homology comparison. Molecular biological identification was made by phylogenetic tree constructed by MEGA 7.0 software. Through the homology comparison of NCBI and the construction of phylogenetic tree by MEGA 7.0 software, nine GABA-producing microorganisms were screened out and identified in this study. They were Bacillus subtilis, Enterococcus faecium, E. avium, Aspergillus tamarii, A. flavus, A. niger, Cladosporium tenuissimum, Penicillium citrinum and Phanerochaete sordida respectively. For the first time, nine GABA-producing microorganisms were screened out and identified in the samples at different time points during the fermenting process of SSP in this study. The results indicated that multiple predominant GABA-producing microorganisms exist in the fermenting process of SSP and may play an important role in the formation of GABA.
Subject(s)
Bacteria , Classification , Metabolism , Chromatography, High Pressure Liquid , Fermentation , Fungi , Classification , Metabolism , Phylogeny , Seeds , Microbiology , Glycine max , Microbiology , gamma-Aminobutyric AcidABSTRACT
Objective To investigate the roles of long noncoding RNA-myocardial infarction-associated transcript (MIAT) on lens epithelial cells (LECs) fibrosis induced by transforming growth factor-β2(TGF-β2).Methods LECs line (SRA01/04) was cultured in conventional DMEM (normal control group) and DMEM containing 10 ng/ml TGF-β2(TGF-β2 induced group) for 48 hours.The morphology of the cells was observed under the optical microscope,and the relative expression levels of M IAT,E-cadherin (E-cad),α-smooth muscle action (α-SMA),collagen Ⅰ (Coll Ⅰ) in protein level and mRNA level were detected by real-time fluorescence quantitative PCR and Western blot,respectively.The cells cultured in DMEM or DMEM containing 10 ng/ml TGF-β2 were transfected by siNRA empty carrier (siNRA group,siNRA+TGF-β2 group) and siRNA-MIAT (siRNA-MIAT group,siNRA-MIAT+ TGF-β2 group) for 48 hours,and the morphology of the cells was observed under the optical microscope,and the relative expression levels of MIAT,E-cadherin (E-cad),α-smooth muscle action (α-SMA),collagen Ⅰ (Coll Ⅰ) in protein level and mRNA level were detected by real-time fluorescence quantitative PCR and Western blot.Results The cells in the normal control group showed the round and polygon in shape,and those in the TGF-β2 induced group showed the spindle-like.Compared with the normal control group,the relative expression levels of MIAT mRNA,α-SMA mRNA and Coll Ⅰ mRNA were significantly elevated (2.497 ± 0.644 vs.0.827 ± 0.062;2.951 ±0.146 vs.1.085±0.517;2.115 ±0.090 vs.1.002 ± 0.088),and the expression of E-Cad mRNA was significantly reduced (0.102±0.027 vs.1.020±0.262) in the TGF-β2 induced group (P =0.045,0.004,0.000,0.025).The expressions of MIAT,α-SMA,Coll Ⅰ and E-Cad showed a similar trend between two groups.The relative expressions of MIAT protein and mRNA were evidently reduced in the SiRNA-MIAT group compared with the siRNA empty vector group (all at P＜0.05).Compared with the siRNA+TGF-β2 group,the relative expressions of α-SMA and Coll Ⅰ in protein and mRNA levels were significantly reduced,and the expressions of E-cad protwin and mRNA were elevated in the siRNA-MIAT+TGF-β2 group (all at P＜0.01).Conclusions MIAT might participate in TGF-β2-induced LECs-EMT.The down-regulation of MIAT in the LECs inhibits the fibrosis of LECs.
ABSTRACT
Long non-coding RNA ( LncRNA) is a class of transcript (>200 nucleotides) that do not encode proteins. It plays an important role in epigenetic regulation and gene expression at transcriptional or post transcriptional level. The abnormal expression of LncRNA may lead to various pathological processes. Diabetic retinopathy ( DR ) is a multifactorial disease. Recent studies have shown that many specific expressions of LncRNAs are closely related to the genesis of DR. In this review, we summarized the recent advances in the function of LncRNA, the regulatory mechanisms of LncRNA involved in the development of DR, and the related therapies.
ABSTRACT
To investigate the microbial species, amount changes as well as the isolation and identification of domain strains at different fermentation time points of Pinelliae Rhizoma Fermentata, and provide basis for exploring the mechanism of Pinelliae Rhizoma Fermentata processing. Five samples were chosen at the time points (0, 18, 36, 54, 72 h) of Pinelliae Rhizoma Fermentata processing. Bacteria, mold and yeast from the samples were cultured; their colonies were counted, and the dominant strains were isolated and purified. The dominant bacteria and dominant fungi were identified by 16S rDNA and 26S rDNA sequencing respectively. The results showed that the bacteria count was low with slow and smooth changes in the fermentation process;while mold and yeast grew dramatically after 54 h culturing and reached 1×107 CFU•mL⁻¹ at the end of fermentation. Through the NCBI homology alignment and phylogenetic tree construction, the dominant bacteria were identified as Streptomyces sp., Bacillus pumilus, B. subtilis, B. aryabhattai and other Bacillus sp.; the dominant yeast was identified as Meyerozyma guilliermondii; the dominant mold were identified as Paecilomyces variotii, Byssochlamys spectabilis, and Aspergillus niger in the processing of Pinelliae Rhizoma Fermentata. The results indicated that multiple microbe species, especially yeast and mold, played a role in the fermentation processing of Pinelliae Rhizoma Fermentata. M. guilliermondii, P. variotii, P. variotii and A. niger and Bacillus sp. can be the crucial factors in the processing of Pinelliae Rhizoma Fermentata.
ABSTRACT
Long-term use of systemic or topical glucocorticoid can cause posterior subcapsular opacities ( PSO ) , named glucocorticoid-induced cataract ( GIC ) . There are many hypotheses on the pathogenesis of GIC. However, no one has well explained the formation of PSO, which leads to no effective approaches in the prevention and/or treatment. A new opinion is that hormones might affect lens epithelial cells through GR - mediated vimentin changes, which eventually result in the formation of GIC. Therefore, the association between vimentin and lens epithelial cell proliferation and differentiation, maybe a new direction for further studies in the pathogenesis of GIC.
ABSTRACT
<p><b>OBJECTIVE</b>To construct, express and purify human fusion proteins composed of a single-chain antibody fragment scFv that recognizes the prostate specific membrane antigen (PSMA) protein, Fdt, HA2 and tp, and to analyze the binding activity of the expressed fusion proteins.</p><p><b>METHODS</b>The fusion protein genes scFv, scFv-tp, and scFv-Fdt-HA2-tp were amplified by PCR, and the genes obtained were then cloned into the expression vector pET28 and expressed in E. coli BL21. The expressed products were identified by SDS-PAGE and Western blot and purified with Ni(2+)-NTA chelating agarose. The antigen-binding activity of the fusion proteins was determined by ELISA.</p><p><b>RESULTS</b>The human anti-PSMA fusion gene was successfully constructed and expressed in M15 as the inclusion body after induced with IPTG. All the target proteins expressed could bind the PSMA antigen.</p><p><b>CONCLUSION</b>Fusion proteins can specifically bind the PSMA antigen. This finding contributes to the study of the targeted delivery of siRNA.</p>
Subject(s)
Humans , Male , Antigens, Surface , Allergy and Immunology , Cloning, Molecular , Electrophoresis, Polyacrylamide Gel , Escherichia coli , Genetics , Allergy and Immunology , Glutamate Carboxypeptidase II , Allergy and Immunology , Polymerase Chain Reaction , RNA, Small Interfering , Allergy and Immunology , Recombinant Fusion Proteins , Genetics , Allergy and Immunology , Single-Chain Antibodies , Genetics , Allergy and ImmunologyABSTRACT
<p><b>BACKGROUND</b>Previous researches about necrotic pancreatic tissue infections are numerous, but the study on systemic infection related to the severe acute pancreatitis (SAP) treatment period is limited. This study aimed to investigate the distribution and drug resistance of pathogenic bacteria in patients who had hepatobiliary surgery for SAP during the past three years.</p><p><b>METHODS</b>A retrospective study was conducted on the distribution, category and drug resistance of pathogenic bacteria in patients who had hepatobiliary surgery for SAP from 2008 to 2011.</p><p><b>RESULTS</b>A total of 594 pathogenic bacteria samples were isolated. Among them 418 isolates (70.4%) were Gram bacteria negative, 142 isolates (23.9%) were Gram bacteria positive, and 34 isolates (5.7%) were found fungi. The most common Gram negative bacteria were Escherichia coli (19.8%), and the dominant Gram positive pathogenic bacteria were Enterococcus faecium. The distribution of SAP-related infectious pathogens was mainly in peritoneal drainage fluid, sputum, bile, and wound secretions. Almost all the Gram negative pathogenic bacteria were sensitive to carbapenum. Extended-spectrum β-lactamases (ESBLs) producing strains were more resistant to penicillins and cephalosprins than the ESBLs non-producing strains. Staphylococcus was sensitive to vancomycin and linezolid. The drug resistance of meticillin-resistant staphylococcus (MRS) to commonly used antibiotics was higher than meticillin-sensitive streptococcus (MSS). Enterococcus sp. exhibited lower drug-resistance rates to vancomycin and linezolid.</p><p><b>CONCLUSIONS</b>Gram negative bacteria were the dominant SAP-related infection after hepatobiliary surgery. A high number of fungal infections were reported. Drug resistant rates were high. Rational use of antibiotics according to the site of infection, bacterial species and drug sensitivity, correctly executing the course of treatment and enhancing hand washing will contribute to therapy and prevention of SAP-related infection and decrease its mortality.</p>
Subject(s)
Humans , Anti-Bacterial Agents , Pharmacology , Gram-Negative Bacteria , Gram-Positive Bacteria , Virulence , Microbial Sensitivity Tests , Pancreatitis , MicrobiologyABSTRACT
<p><b>OBJECTIVE</b>To determine whether circulating level of catestatin (CST) could provide prognostic information independently of conventional risk markers for the development of in-hospital heart failure in patients with ST-segment elevation myocardial infarction (STEMI).</p><p><b>METHODS</b>The data of 120 STEMI patients (mean age: 61 years, 73% male) were collected from the Second Hospital of Shanxi Medical University and Taiyuan Central Hospital between November 2010 and September 2011.The patients were categorized into 4 groups according to CST (ng/L) quartile: ≤ 74.72, 74.73-79.67, 79.68 - 84.21 and ≥ 84.22 ng/L. Clinical features, therapeutic approaches were compared among groups. The patients were also grouped according to Killip class: Killip level I (n = 68), Killip level II (n = 23), Killip level III (n = 18), Killip level IV (n = 11). CST, NE and NT-proBNP were compared among groups. The Spearma rank correlation and multivariate logistic regression analysis were applied to determine the association between risk factors and in-hospital heart failure. Receiver-operator characteristic (ROC) curve was performed to evaluate the power of CST and NT-proBNP on predicting in-hospital heart failure.</p><p><b>RESULTS</b>Gender, hospital days, past history of smoking, hypertension, myocardial infarction, CK-MB peak level, TnI peak level, heart rate, blood pressure, blood glucose, blood lipid levels on admission and early reperfusion therapy were similar among groups. Patients with higher CST values were more likely to be older, to have lower body mass index, to have higher white blood cell count, CysC, hs-CRP, NE, NT-proBNP, past history of angina, diabetes mellitus, being diuretic users, and to have a lower ejection fraction (all P < 0.05). Higher CST levels were also associated with increased risk of heart failure (P < 0.05). In proportion with the deterioration of the cardiac function, CST, NE, NT-proBNP concentration gradually increased (all P < 0.05). Spearman rank correlation analysis showed that the CST was negatively correlated with LVEF (r(s) = -0.923, P < 0.001) and positively correlated with NT-proBNP (r(s) = 0.884, P < 0.001). After multivariate adjustment, CST remained to be an independent risk factor for the development of in-hospital heart failure (OR = 1.125, 95%CI: 1.056 - 1.198;P < 0.001). The area under the ROC curve of CST and NT-proBNP was 0.777 and 0.874. Using CST = 77.29 ng/L as a cut-off value, the sensitivity was 92.8% and specificity was 70.6% for predicting the development of in-hospital heart failure.</p><p><b>CONCLUSION</b>The plasma CST level is an independent predictor for the development of in-hospital heart failure in patients with STEMI.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Catechols , Pharmacology , Chromogranin A , Blood , Heart Failure , Diagnosis , Inpatients , Myocardial Infarction , Blood , Diagnosis , Peptide Fragments , Blood , Prognosis , Prospective Studies , Risk FactorsABSTRACT
<p><b>OBJECTIVE</b>The aim of the study was to detect the expression of Ki67 and P53 proteins in the gingival tissue before and after wearing three kinds of dental casting alloy crowns.</p><p><b>METHODS</b>The three kinds of dental casting alloys (58% golden alloy, NiCr alloy, NiCr alloy excluding Be) were used to make full crowns for 3 dogs in each group. Another 3 dogs were taken as control. The immunohistochemistry Envision method was used to measure the expression of Ki67 and P53 proteins in the gingival tissue before wearing the crowns, 2 weeks, 1 month, 2 months, 3 months after wearing the crowns.</p><p><b>RESULTS</b>The expression of Ki67 and P53 proteins in gingival tissue increased 1 month after wearing NiCr alloy and NiCr alloy excluding Be, then decreased gradually. And the expression of Ki67 and P53 proteins in 58% golden alloy group was similar to that in control. No pathological change was observed in all samples.</p><p><b>CONCLUSION</b>Two kinds of NiCr alloy crowns both can increase the expression of Ki67 and P53 proteins in gingival tissue, but 58% golden alloy crowns can not. So compared with NiCr alloy crowns, 58% golden alloy crowns have better biological properties. And none of three kinds of dental alloy crowns may induce long-term abnormal proliferation in gingival tissue.</p>
Subject(s)
Animals , Dogs , Alloys , Chromium Alloys , Crowns , Dental Alloys , GingivaABSTRACT
<p><b>OBJECTIVE</b>To determine whether the roughness of titanium implant can influence its osseointegration by affecting the growth, alkaline phosphatase (ALP) production and expression of core binding factor alpha 1 subunit (Cbfα1) of osteoblasts.</p><p><b>METHODS</b>Totally 48 titanium disc specimens, 15 mm in diameter and 2 mm in thickness, were included in the study and divided equally into 4 groups with 12 specimens in each group. Specimens were coarsened by sandblasting with carborundum granula and acid etching with mixing liquid of hydrochloric acid and sulphuric acid under diverse conditions. In the four groups, three were treated with different surface roughness: micro-roughness [(1.00 ± 0.20) µm], midrange roughness [(1.67 ± 0.08) µm] and severe roughness [(2.40 ± 0.20) µm], while the group untreated with surface roughness [(0.12 ± 0.03) µm] was set as control. Scanning electron microscope, acridine orange fluorescence staining and coomassie brilliant blue staining were used to observe morphology and growth of osteoblasts incubating on these specimens. Enzyme linked immunosorbent assay (ELISA) and fluorescence quantitative real-time polymerase chain reaction were used to evaluate ALP production and gene expression of Cbfα1 of osteoblasts among different groups.</p><p><b>RESULTS</b>Growth, ALP production and Cbfα1 mRNA expression of osteoblasts in experimental groups were higher than those in control group (P < 0.05). Significant differences of these data were also found among three experimental groups (P < 0.05). Midrange roughness group showed the highest level of gene expression of Cbfα1 mRNA, which was 0.93 ± 0.03. While that in the micro-roughness group (0.50 ± 0.03) came second, and the severe roughness group had the lowest data, which was 0.37 ± 0.07.</p><p><b>CONCLUSIONS</b>Results indicated that rough surface was more suitable for the adherence and propagation of the osteoblasts than smooth one did. Surface with roughness of 1-2 µm may be a better choice for osseointegration between osteoblasts and dental implants than others are.</p>
Subject(s)
Humans , Alkaline Phosphatase , Cell Differentiation , Core Binding Factor Alpha 1 Subunit , Metabolism , Dental Implants , Microscopy, Electron, Scanning , Osseointegration , Osteoblasts , Metabolism , Prostheses and Implants , Surface Properties , TitaniumABSTRACT
<p><b>OBJECTIVE</b>To investigate the intensity changes of different thickness ratios of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic before and after Hertzian contact cyclic fatigue.</p><p><b>METHODS</b>Disk-shaped specimens of different thickness ratios of Empress II glass ceramic and GI-II glass-infiltrated alumina ceramic were respectively fabricated. Hertzian contact technique was imposed on the specimens. Critical loads of the specimens before and after 10(5) cycles loading were recorded.</p><p><b>RESULTS</b>The average values of critical loads of all specimens reduced significantly after cycles loading (P < 0.05), and critical loads declined with diminishing thickness of the core ceramic. The critical load of GI-II glass-infiltrated alumina ceramic was significantly higher than Empress II glass ceramic before and after cycle loading(P < 0.05).</p><p><b>CONCLUSION</b>Cycle loading can reduce the strengths of the two kinds of dental ceramic, and the latter is better than the former in the resistance to fracture and cyclic fatigue. Critical loads of the two kinds of dental ceramic are mainly influenced by the core ceramic's strength and thickness.</p>
Subject(s)
Humans , Aluminum Oxide , Ceramics , Dental Porcelain , Glass , Materials TestingABSTRACT
<p><b>OBJECTIVE</b>To investigate the submerged culture conditions and nutritional requirments for the production of mycelial biomass and exopolysaccharides (EPS) by medicinal mushroom Phellinus baumii.</p><p><b>METHOD</b>The carbon sources, nitrogen sources, inoculum volume, initial pH and temperature were investigated based on shake flask cultures, respectively.</p><p><b>RESULT</b>The glucose was the most suitable carbon source for both mycelial biomass and EPS production, soy peptone was favorable nitrogen sources for both mycelial biomass and EPS production. The optimal inoculum volume, initial pH and temperature for both mycelial growth and EPS production were 6%, 6.0 and 28 degrees C, respectively.</p><p><b>CONCLUSION</b>The study obtained basic datas for large-scale submerged culture of P. baumii.</p>
Subject(s)
Basidiomycota , Metabolism , Biomass , Hydrogen-Ion Concentration , Mycelium , Metabolism , Polysaccharides , TemperatureABSTRACT
<p><b>OBJECTIVE</b>To compare the difference in strength degradation and morphology damage of two dental ceramic materials after Hertzian contact cyclic fatigue.</p><p><b>METHODS</b>Hertzian contact technique was used to investigate the response of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic to cyclic fatigue. Critical loads of specimens after different fatigue cycles were recorded.</p><p><b>RESULTS</b>For Empress II glass ceramic, critical load had significantly difference between specimens after 10(5) cycles loading. No significant difference of critical load was found in GI- II glass-infiltrated alumina ceramic after cycles loading.</p><p><b>CONCLUSION</b>GI- II glass-infiltrated alumina ceramic has better capability in resistance to cyclic loading. It may attribute to microstructure of material. Empress II glass ceramic shows a brittle damage model.</p>
Subject(s)
Humans , Aluminum Oxide , Aluminum Silicates , Ceramics , Dental Porcelain , Glass , Materials TestingABSTRACT
<p><b>OBJECTIVE</b>To test the corrosion behavior of three kinds of dental casting alloys and to investigate the effect of the released metal ions on the DNA damage of dog buccal mucosal cells.</p><p><b>METHODS</b>Three kinds of frequently used dental casting alloys were used to make full crowns for dogs. The concentration of the released metal ions was measured after the restoration of 2 weeks, 1 month, 2 months and 3 months. The DNA damage of buccal mucosal cells was studied by the method of SCGE.</p><p><b>RESULTS</b>The metal ions released from NiCr and NiCrBe were detected in buccal mucosal cells while the amount of the ions released from noble alloy (gold 58%) was too small to be detected. The DNA damage of mucosal cells increased after restoration of NiCr and NiCrBe crowns.</p><p><b>CONCLUSION</b>The noble alloy (gold 58%) is most corrosion resistant of the three alloys and has good biocompatibility. The NiCr and NiCrBe are prone to corrode and have cytotoxicity to cells.</p>
Subject(s)
Animals , Dogs , Alloys , Corrosion , Crowns , DNA Damage , Dental Alloys , Gold , Ions , Mouth MucosaABSTRACT
<p><b>OBJECTIVE</b>To evaluate the incidence of precore mutation in HBeAg negative HBV infected patients and the therapeutic effect of the immune therapy (levamisole + HBV vaccine + dipyridamole) on patients chronically infected by HBV with precore mutation.</p><p><b>METHODS</b>The precore region of HBV from the HBeAg (-) chronic hepatitis patients was sequenced and the patients suffered from HBV with precore mutation were treated with immune therapy.</p><p><b>RESULTS</b>The precore mutation rate was 10/12. The therapeutic effect of the immune therapy on the precore mutation patients (5/7) was better than that on the HBsAg(+), HBeAg(+) patients (2/11), P less than 0.05.</p><p><b>CONCLUSION</b>The precore mutation rate was quite high in the HBsAg(+), HBeAg(-) patients we studied. The immune-therapy has some therapeutic effects on the patients with precore mutation. But the number of cases was too small, further study is needed.</p>