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1.
Artigo em Chinês | WPRIM | ID: wpr-1006295

RESUMO

Sesquiterpenoids are natural compounds composed of 15 carbon atoms, which can be divided into sesquiterpene alcohols, ketones, lactones, aldehydes, and carboxylic acids according to oxygen groups. These compounds are widely distributed in nature, and their physiological activities are diverse. For example, many sesquiterpenes with potential anticancer effects have been found for anti-tumor effects, including cytotoxicity, antioxidant, immune regulation, cell proliferation, and so on. In addition, some sesquiterpenoids have good application prospects in antibacterial, anti-inflammatory, and anti-cardiovascular diseases. Malignant tumors, inflammation, bacterial diseases, and cardiovascular diseases are the main diseases that cause human death, and natural products have unique advantages in the treatment of these diseases. Therefore, the development of new drugs that are easy to promote has become a new research hotspot. In this paper, the sesquiterpenes extracted from the natural components of Chinese herbs and plants with anti-tumor, anti-inflammatory, antibacterial, and anti-cardiovascular activities, such as Xanthium, Atractylodes, Convolvulus, Acanthium, Ligularia, Artemisia, Ligularia, Ligularia, Labiaceae Mint, Acanthophyllum, Turmeria, Ginger, and other Chinese herbs and plants, were discussed. The biological activities and related mechanisms of this compound were reviewed, which provided a reference for further research and clinical application of sesquiterpenes.

2.
Artigo em Chinês | WPRIM | ID: wpr-1021820

RESUMO

BACKGROUND:β-amyloid protein and Tau protein have adverse effects on the cognitive function of Alzheimer's disease patients,and Notch1 and Caspase-3 can regulate the expression of β-amyloid protein and Tau protein.It is not clear whether Notch1 and Caspase-3 mediate the process of aerobic exercise to improve the cognitive ability of Alzheimer's disease patients.At present,there is a lack of studies on the effect of long-term aerobic exercise on the expression of Notch1 and Caspase-3 in the hippocampus of Alzheimer's disease mice. OBJECTIVE:To observe the expression of Notch1 and Caspase-3 in the hippocampus of Alzheimer's disease mice undergoing long-term aerobic exercise and to investigate the effects of Notch1 and Caspase-3 in Alzheimer's disease mice. METHODS:Wild type and APP/PS1 double-transgenic Alzheimer's disease mice aged 3 months were randomly divided into four groups:wild control group,wild exercise group,Alzheimer's disease control group and Alzheimer's disease exercise group,with 20 mice in each group.Mice in the control groups were not subjected to exercise,while those in the exercise groups received aerobic exercise intervention for 5 months.After the exercise intervention,Morris water maze was used to detect the spatial learning and memory ability of mice.Real-time PCR,immunofluorescence and western blot were used to detect the expressions of Aβ1-42,Tau,Notch1 and Caspase-3 in the hippocampal tissues of mice in each group. RESULTS AND CONCLUSION:The spatial learning and memory ability of Alzheimer's mice was significantly worse than that of wild-type mice(P<0.05).The spatial learning and memory ability of mice in the exercise groups were significantly better than that in the corresponding control groups(P<0.05).The expressions of Aβ1-42,Tau,Notch1 and Caspase-3 in the hippocampus were significantly higher in the Alzheimer's disease control group than the wild control group(P<0.05)and were significantly lower in the Alzheimer's disease exercise group than the Alzheimer's disease control group(P<0.05).To conclude,long-term aerobic exercise can improve the spatial learning and memory ability of Alzheimer's disease mice,which may be related to the decreased expression of Notch1,Caspase-3,Aβ1-42 and Tau protein in the hippocampus of Alzheimer's disease mice.

3.
International Eye Science ; (12): 1127-1131, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1032360

RESUMO

AIM: To analyze changes in the ocular surface parameters of keratoconus after long-term wearing of rigid gas permeable contact lens(RGPCL).METHODS:Prospective case study. A total of 113 keratoconus patients(213 eyes)fitted with RGPCL in the optometry center of Gansu Provincial Hospital from January 2018 to January 2022 were included. They were divided into three groups according to the severity of keratoconus, including 42 cases(80 eyes)in mild keratoconus group, 54 cases(102 eyes)in moderate keratoconus group and 17 cases(31 eyes)in severe keratoconus group. Furthermore, the non-invasive tear break-up time(NIBUT), non-invasive tear meniscus height(NITMH), red eye index, lipid layer thickness, fluorescent corneal staining, meibomian gland secretory function, Schirmer I test and ocular surface disease index(OSDI)scores were observed by Keratograph analyzer before and after wearing RGPCL for 1 wk, 1, 3, 6, 12 mo, respectively.RESULTS: There were no statistical significance in the age, NIBUT, NITMH, lipid layer thickness, meibomian gland secretory function and Schirmer I test among the three groups(P>0.05), while there were statistical significance in the sphere, cylinder, spherical equivalent, best corrected visual acuity(BCVA), non-contact intraocular pressure(IOPNCT), anterior, posterior corneal surface Kmax, corneal surface thickness at the thinnest point, eye redness index, fluorescent corneal staining, and OSDI(P<0.05). In the mild keratoconus group, NIBUT had statistical differences at 3, 6 and 12 mo after wearing RGPCL(P<0.05), NITMH had statistical differences in 6 and 12 mo(P<0.05), the eye redness index, fluorescent corneal staining and OSDI scores had statistical differences in 1 wk and 1 mo(P<0.05), and lipid layer thickness and meibomian gland secretory function had statistical differences in 12 mo(P<0.05). In the moderate keratoconus group, there were statistical differences in NIBUT at 6 and 12 mo after wearing lenses(P<0.05); there were statistical differences in the NITMH, lipid layer thickness and meibomian secretory function at 12 mo after wearing lens(P<0.05); there were statistical differences in the eye redness index at 1 wk, 1 and 3 mo after wearing RGPCL(P<0.05); there were statistical differences in the fluorescent corneal staining at 1 wk after wearing RGPCL(P<0.05); there were statistical differences in the OSDI at 1 wk and 1 mo after wearing RGPCL(P<0.05). In the severe keratoconus group, there were statistical differences in the NIBUT, NITMH and eye redness index at 1 wk, 1, 3, 6 and 12 mo after wearing RGPCL(P<0.05); there were statistical differences in the lipid layer thickness at 6,12 mo after wearing RGPCL(P<0.05); there were statistical differences in the fluorescent corneal staining and OSDI scores at 1 wk, 6 and 12 mo after wearing RGPCL(P<0.05); there were statistical differences in the meibomian secretory function at 6 and 12 mo after wearing RGPCL(P<0.05); and there were statistical differences in the Schirmer I test at 12 mo after wearing RGPCL(P<0.05).CONCLUSION: Long-term wearing of RGPCL can affect the ocular surface microcirculation in keratoconus patients, thus making differences in patients subjective. However, it has no significant impact on the visual quality of patients. Therefore, long-term wearing of RGPCL is safely to control the progression of keratoconus.

4.
Artigo em Chinês | WPRIM | ID: wpr-1022457

RESUMO

Objective:To investigate the application value of carbon nanoparticle tracer in lymph node dissection for Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG).Methods:The retrospective cohort study was conducted. The clinicopathological data of 147 patients with Siewert type Ⅱ and Ⅲ AEG who were admitted to Shengli Petroleum Central Hospital from June 2015 to July 2020 were collected. There were 109 males and 38 females, aged (65±9)years. All the patients underwent laparoscopic-assisted radical resection of AEG via esophageal hiatus. Of 147 patients, 61 cases not injected with carbon nanoparticle tracer preoperatively were allocated into control group and 86 cases injected with carbon nanoparticle tracer preoperatively were allocated into experimental group. Observation indicators: (1) surgical and postoperative situations; (2) influencing factors analysis of No.10 lymph nodes metastasis. Measurement data with normal distribution were represented as Mean± SD, and comparison between groups was conducted using the t test. Count data were represented as absolute numbers or percentages, and comparison between groups was analyzed by the chi-square test. Univariate analysis was conducted by statistic methods based on data type, and multivariate analysis was conducted by the Logistic step-wise regression model. Results:(1) Surgical and postoperative situations. Patients of the experimental group and control group completed laparoscopic-assisted radical resection of AEG via esophageal hiatus successfully. There was no significant difference in the operation time, volume of intraoperative blood loss, the total number of lymph node dissection, the number of the first station, the second station and positive lymph nodes between the two groups ( P>0.05). For the experimental group, the black staining rate of lymph nodes was 57.937%(1 365/2 356), the black staining rate of the first station and second station lymph nodes was 77.989%(1 024/1 313) and 43.691%(232/531), the black staining rate of Siewert type Ⅱ and Ⅲ AEG patients was 56.855%(423/744) and 58.437%(942/1 612), respectively. The lymph node metastasis rate was 19.091%(815/4 269) of 147 patients, 18.573%(242/1 303)of Siewert type Ⅱ AEG patients and 19.319%(573/2 966) of Siewert type Ⅲ AEG patients. For Siewert type Ⅱ AEG patients, the metastasis rate of No.1, 2, 3, 4sa, 4sb, 7, 8a, 11p lymph nodes was more than 10%, the metastasis rate of No.4d, 5, 6, 9, 10, 11d, 12a lymph nodes was lower than 10%. For Siewert type Ⅲ AEG patients, the metastasis rate of No.1, 2, 3, 4sa, 4sb, 7, 8a, 10, 11p and lower mediastinal lymph nodes was more than 10%, the metastasis rate of No.4d, 5, 6, 9 11d, 12a and lower mediastinal lymph nodes was lower than 10%. There was no significant difference in the Clavien Dindo classification of postoperative complications between the two groups ( P>0.05). (2) Influencing factors analysis of No.10 lymph nodes metastasis. Results of multivariate analysis showed that tumor T staging and degree of tumor differention was an independent influencing factor for No.10 lymph nodes metastasis ( P<0.05). Conclusions:For Siewert type Ⅱ and Ⅲ AEG patients, the application of carbon nano-partide tracer can not increase the number of lymph node dissection. The second station lymph node dissection should be paid attention for Siewert type Ⅱ AEG. Tumor T staging and degree of tumor differentiation are independent influencing factors for No.10 lymph nodes metastasis.

5.
Chinese Journal of Biotechnology ; (12): 614-624, 2023.
Artigo em Chinês | WPRIM | ID: wpr-970395

RESUMO

Papaya, which is mainly cultivated in the southeastern region of China, is one of the four famous fruits in Lingnan. It is favored by people because of its edible and medicinal value. Fructose-6-phosphate, 2-kinase/fructose-2, 6-bisphosphatase (F2KP) is a unique bifunctional enzyme with a kinase domain and an esterase domain that catalyzes the synthesis and degradation of fructose-2, 6-bisphosphate (Fru-2, 6-P2), an important regulator of glucose metabolism in organisms. In order to study the function of the gene CpF2KP encoding the enzyme in papaya, it is particularly important to obtain the target protein. In this study, the coding sequence (CDS) of CpF2KP, with a full-length of 2 274 bp, was got from the papaya genome. The amplified sequence of full-length CDS was cloned into the vector PGEX-4T-1 which was double digested with EcoR I and BamH I. The amplified sequence was constructed into a prokaryotic expression vector by genetic recombination. After exploring the induction conditions, the results of SDS-PAGE showed that the size of the recombinant GST-CpF2KP protein was about 110 kDa. The optimum IPTG concentration and temperature for CpF2KP induction were 0.5 mmol/L and 28 ℃, respectively. The purified sin[A1] gle target protein was obtained after purifying the induced CpF2KP protein. In addition, the expression level of this gene was detected in different tissues, and showed that the gene was expressed at the highest level in seeds and the lowest in pulp. This study provides an important basis for further revealing the function of CpF2KP protein and studying the involved biological processes of this gene in papaya.


Assuntos
Humanos , Carica/genética , Proteínas Recombinantes , Metabolismo dos Carboidratos , Clonagem Molecular , China
6.
Acta Pharmaceutica Sinica B ; (6): 258-270, 2021.
Artigo em Inglês | WPRIM | ID: wpr-881135

RESUMO

Liposomes have made remarkable achievements as drug delivery vehicles in the clinic. Liposomal products mostly benefited from remote drug loading techniques that succeeded in amphipathic and/or ionizable drugs, but seemed impracticable for nonionizable and poorly water-soluble therapeutic agents, thereby impeding extensive promising drugs to hitchhike liposomal vehicles for disease therapy. In this study, a series of weak acid drug derivatives were designed by a simplistic one step synthesis, which could be remotely loaded into liposomes by pH gradient method. Cabazitaxel (CTX) weak acid derivatives were selected to evaluate regarding its safety profiles, pharmacodynamics, and pharmacokinetics. CTX weak acid derivative liposomes were superior to Jevtana® in terms of safety profiles, including systemic toxicity, hematological toxicity, and potential central nerve toxicity. Specifically, it was demonstrated that liposomes had capacity to weaken potential toxicity of CTX on cortex and hippocampus neurons. Significant advantages of CTX weak acid derivative-loaded liposomes were achieved in prostate cancer and metastatic cancer therapy resulting from higher safety and elevated tolerated doses.

7.
Artigo em Chinês | WPRIM | ID: wpr-608653

RESUMO

Mesenchymal stem cells (MSCs) have good immune regulatory function,can inhibit many immune cell proliferation,direct effects on activation and proliferation of T cell,play a role in immune regulation by Treg cells or by the secretion of soluble factors regulating Thl/Th2 secretion and reaction equilibrium,inhibit the inflammation through the anti-inflammatory,regulation of cytokines expression at the same time,so reduce the expression levels of matrix metalloproteinase-2 and-9,which may promote lacrimal gland tissue damage,and thus play a role in immune regulation.MSCs can reduce the autoimmune dry eye clinical index,recovery secretion function of part lacrimal gland.This article reviews the research advances in inmmmne regulation of MSCs on autoimmune dry eye.

8.
Artigo em Chinês | WPRIM | ID: wpr-609885

RESUMO

Objective To establish the model of autoimmune dry eye and analyze the level of cytokines and the pathological changes of autoimmune dry eye rabbits treated with human umbilical cord mesenchymal stem cells (MSCs).Methods Twentyfour female New Zealand rabbits were randomly divided into three groups:Normal control group,dry eye group and MSCs treatment group,8 cases in each group.After treated with MSCs for six weeks,the pathological changes were observed,and the expression of Th1 and Th17 cell differentiation related cytokines mRNA in lacrimal gland tissue was detected by real-time quantitative PCR.The percentage of regulatory T cells (CD4 +Foxp3 + cells) in the lacrimal gland and spleen tissues of the dry eye model group and MSCs treatment group was measured by flow cytometry.Results After treatment with MSCs for 6 weeks,HE staining from each rabbit lacrimal gland showed that,the normal control group showed no or only a few lymphocytes;The lacrimal gland cells were atrophied in the dry eye group,the distribution of lymphocyte scattered around the gland and small blood vessels;Compared with dry eye group,the lacrimal gland lymphocyte infiltration reduced in MSCs treatment group,and the cell morphology were better.Compared with dry eye group,lymphocyte infiltration and aggregation in the conjunctival conjunctiva in MSCs treatment group were significantly reduced,the epithelial structure was intact,and the degeneration and atrophy cells were rare.The expression of inflammatory factors including interferon-γ(IFN-γ),Interleukin-17 (IL-17) and transcription factor T-bet mRNA were decreased in MSCs treatment group,there were significant difference compared with dry eye group (all P < 0.05);Thl7 cell associated cytokines IL-17 expression levels were decreased,but no significant difference was found between two groups (P > 0.05);The expression of transcription factor RORrt mRNA in dry eye group was significantly decreased,the difference was statistically significant (P < 0.05).The expression of inflammatory factors TNF-α in the lacrimal gland tissue of MSCs treatment group was significantly lower than that in the dry eye model group,while the expression of the anti-inflammatory factor TGF-β was significantly higher than that in the dry eye model group,and the differences were statistically significant (all P<0.05).The regulatory T cells (CD4 + Foxp3 + cells) in the lacrimal gland of dry eye model group accounted for 10% of lymphocytes was,while the treatment group accounted for 27.8%,MSCs group was significantly higher than dry eye group,the difference was statistically significant (P < 0.05).Conclusion MSCs can reduce the histopathological changes of the immune dry eye,and they may have immunoregulatory effects on autoimmune dry eye.The mechanisms of immunomodulatory effects may be related to the balance of inflammatory cytokines and anti-inflammatory cytokines.

9.
Artigo em Chinês | WPRIM | ID: wpr-309072

RESUMO

<p><b>OBJECTIVE</b>The objective of this paper is to analyze the stress distribution in the deep wedge-shaped defective mandibular first premolars restored with different methods.</p><p><b>METHODS</b>Three-dimensional finite element models of mandibular first premolar with deep wedge-shaped defect were created. The model, which was untreated after root canal treatment, served as the control group. Then, according to different treatment designs, four experimental groups were established as follows: resin filling (A), post restoration after resin filling (B), crown restoration after resin filling (C), and post and crown restoration after resin filling (D). Four different post materials were then chosen for establishing the subgroup models: fiber post (B1, D1), AuPd post (B2, D2), pure Ti post (B3, D3), and CoCr post (B4, D4). A force of 100 N was applied at a 30° angle on the buccal-inclined surface near the top of the buccal cusp. The maximum principal stress and Von Mises stress were investigated using finite element analysis software.</p><p><b>RESULTS</b>1) For the control group, the maximum principal stress and Von Mises stress of the residual dentine were the same as those of the tip of the defect. 2) Compared with the control group, the maximum principal stress and Von Mises stress of groups A, B, C, and D decreased greatly (P<0.05). The maximum principal stress and Von Mises stress of groups C and D with crowns were similar. The maximum principal stress and Von Mises stress of the post-dentine surface of groups B and D with fiber post were less than those in the cast metal post models (P<0.05). 3) The displacement of the buccal cusp of group A was similar to that of the control group (P>0.05) and larger than those in groups B, C, and D (P<0.05).</p><p><b>CONCLUSIONS</b>It is necessary for deep wedge-shaped defective teeth to be treated with full crowns, but a post is not necessary. If a post is used, fiber post with elastic modulus closer to the dentine is more suitable than metal post.
.</p>


Assuntos
Humanos , Dente Pré-Molar , Coroas , Dentina , Análise de Elementos Finitos , Técnica para Retentor Intrarradicular , Tratamento do Canal Radicular , Coroa do Dente
10.
Artigo em Chinês | WPRIM | ID: wpr-507193

RESUMO

Objective To study genotyping and molecular epidemiology distribution of GBS pathogenic strains of GBS positive pregnant women in Guangzhou,for GBS pathogenic strains of rapid molecular diagnosis and epidemiological surveillance pro-vide certain theoretical basis and method.Methods In the Guangzhou area,used multi stage stratified sampling method col-lecting GBS positive pregnant women’s reproductive tract specimens from January to December 2015,drug sensitivity quality control standard strains:Streptococcus pneumoniae (ATCC49619)and Staphylococcus aureus (ATCC25923),took culture of bacterial,strain,identification,DNA extraction,PCR,gene detection method,through the relevant software for data analy-sis,analyzed GBS strains of gene and molecular epidemiology.Results In the study,collected 2 812 samples of secretions,af-ter identification of strains isolated from 178 strains of pathogenic GBS strains,the detection rate was 6.33%.GBS patho-genic strains to linezolid vancomycin,penicillin,nitrfurantion and other antimicrobial drug resistance rate was 0,GBS parho-genic strains to ampicillin,ciprfloxacin moxifloxacin and levofloxacintesistant parts,the restance rates were 1.1%,16.9%, 18.0% and 22.5%,but GBS pathogenic strains to erythromycin,clindamycin tetracydine antibiotics showed a high resistance rate,the resistance rates were 50.6%,47.8%(of which 20 cases of erythromycin induced clindamycin resistance accouted for 23.5%)and 73.0%.Among them,65 strains of GBS detected the mreA gene,56 strains of GBS detected the ermB gene,36 strains of GBS detected the mefA gene,28 strains of GBS detected the mefE gene,5 strains of GBS detected the ermA gene, ermC gene was not detected in the gene.Among them,carried five multidrug resistance gene of 3 strains (1.6 9%)and 4 kinds of resistant gene carried with 15 strains (8.43%),carried three resistance genes of 19 strains (10.67%),2 kinds of resistant gene carrying a 25 strains (14.04%),carried the resistance gene of 5 strains (2.81%),did not carry resistance gene of 1 strain (0.56%).The nucleotide sequences of the five drug resistance genes were 100%,and no gene mutation oc-curred.Conclusion The main GBS disease resistant gene was mreA,ermA,ermB,mrfA,mefE and its nucleotide sequence homology was 100%.The clinical need to strengthen the detection of resistant gene and molecular level and guide clinical more scientific and rational drug use.

11.
Artigo em Chinês | WPRIM | ID: wpr-317729

RESUMO

<p><b>OBJECTIVE</b>This study investigated the influence of different designs and porcelain/glaze firing on the marginal and internal fit of three kinds of computer aided design/computer aided manufacturing (CAD/CAM) zirconia ceramic implant-supported crowns.</p><p><b>METHODS</b>Three groups of zirconia ceramic implant-supported crowns with different designs were produced from copings by using a Cercon CAD/CAM system (n = 8). The first two groups comprised double-layer crowns (zirconia coping + veneer) with regular (Group A) and full circumferential zirconia-collar marginal designs (Group B). The third group was composed of anatomic single-layer zirconia crowns without cores (Group C). Initially, the marginal and internal gaps of the copings and crowns were individually replicated by light-body silicon and then measured by micro-computed tomography scanning before and after porcelain/glaze firing. Five measurements were employed: vertical marginal gap (MG); horizontal marginal discrepancy (HMD); chamfer area (CA); axial wall (AW); and axial-occlusal transition area (AOT). Statistical analyses were performed by SPSS 17.0.</p><p><b>RESULTS</b>HMD measurements in Group A were statistically higher than those in Groups B and C (P < 0.05), regardless of whether the values were obtained before or after porcelain/glaze firing. By contrast, the HIMD measurements in Groups B and C showed no significant difference (P > 0.05). Moreover, no differences were noted in MG, CA, AW, and AOT among the three groups (P > 0.05). All the measurements in the three groups showed no significant change after porcelain/glaze firing (P > 0.05), except for MG in Group A, which significantly decreased (P < 0.05).</p><p><b>CONCLUSION</b>The marginal fits of the double-layer crowns with full circumferential zirconia-collar and the anatomic single-layer zirconia crowns were superior to that of the double-layer crowns with regular margins. The MG of the crowns with regular margins was obviously influenced by porcelain firing.</p>


Assuntos
Desenho Assistido por Computador , Coroas , Porcelana Dentária , Planejamento de Prótese Dentária , Microtomografia por Raio-X , Zircônio
12.
Artigo em Chinês | WPRIM | ID: wpr-317778

RESUMO

<p><b>OBJECTIVE</b>This study was performed to investigate the electromyographic (EMG) activity of the masseter muscle and the anterior temporalis muscle, as well as the masticatory efficiency after insertion of the dentures in edentulous individuals whose maxillomandibular horizontal relationship records were obtained with three different methods.</p><p><b>METHODS</b>Ten edentulous individuals were enrolled in this study. Three types of complete dentures for these 10 edentulous patients were made according to their different maxillomandibular horizontal relationship records. The maxillomandibular horizontal relationship of complete dentures was recorded by three methods. In the first method (A), the maxillomandibular horizontal relationship was determined at the gothic arch tracing apex. In the second method (B), the relationship was 1 mm anterior to the tracing apex with the gothic arch. In the last method (C), the horizontal jaw relation was recorded by natural chewing. The muscular activities of the three complete dentures were examined by EMG. The masticatory efficiency was evaluated based on the absorbance. The differences among the dentures were statistically analyzed with SPSS 17.0.</p><p><b>RESULTS</b>The muscular activities of dentures B and C were much higher than that of denture A during clenching in the center occlusion and during chewing (P<0.05). The highest asymmetry index was found indenture C, which was significantly higher than those of dentures A and B (P<0.05). A statistically significant increase in the absorbance was observed between dentures B and C (P<0.05); otherwise, no statistically significant differences were observed (P>0.05) between B and C.</p><p><b>CONCLUSIONS</b>Given the limitations of this experimental design, in edentulous individuals the maxillomandibular horizontal relationship recorded at 1 mm anterior to the tracing apex with the gothic arch can improve the function of masticatory muscles and strengthen masticatory performance.</p>


Assuntos
Humanos , Oclusão Dentária Central , Prótese Total , Eletromiografia , Mastigação , Boca Edêntula , Músculo Temporal
13.
Artigo em Chinês | WPRIM | ID: wpr-309141

RESUMO

<p><b>OBJECTIVE</b>This study aimed to investigate the influence of coping material and porcelain firing on the marginal and internal fit of computer-aided design/computer-aided manufacturing (CAD/CAM) of zirconia ceramic implant- and titanium ceramic implant-supported crowns.</p><p><b>METHODS</b>Zirconia ceramic implant (group A, n = 8) and titanium metal ceramic implant-supported crowns (group B, n = 8) were produced from copings using the CAD/CAM system. The marginal and internal gaps of the copings and crowns were measured by using a light-body silicone replica technique combined with micro-computed tomography scanning to obtain a three-dimensional image. Marginal gap (MG), horizontal marginal discrepancy (HMD), and axial wall (AW) were measured. Statistical analyses were performed using SPSS 17.0.</p><p><b>RESULTS</b>Prior to porcelain firing, the measurements for MG, HMD, and AW of copings in group A were significantly larger than those in group B (P < 0.05). After porcelain firing, the measurements for MG of crowns in group A were smaller than those in group B (P < 0.05), whereas HMD and AW showed no significant difference between the two groups (P > 0.05). Porcelain firing significantly reduced MG (P < 0.05) in group A but significantly increased MG, HMD, and AW in group B (P < 0.05) HMD and AW were not influenced by porcelain firing in group A (P > 0.05).</p><p><b>CONCLUSION</b>The marginal fits of CAD/CAM zirconia ceramic implant-supported crowns were superior to those of CAD/CAM titanium ceramic-supported crowns. The fits of both the CAD/CAM zirconia ceramic implant- and titanium ceramic implant-supported crowns were obviously influenced by porcelain firing.</p>


Assuntos
Humanos , Cerâmica , Desenho Assistido por Computador , Coroas , Porcelana Dentária , Planejamento de Prótese Dentária , Titânio , Microtomografia por Raio-X , Zircônio
14.
Artigo em Chinês | WPRIM | ID: wpr-261082

RESUMO

<p><b>OBJECTIVE</b>To evaluate the influence of eugenol-containing and resin-containing endodontic sealers on the bond strength of fiber posts using different strategies of root canal irrigation.</p><p><b>METHODS</b>Forty-eight mandibular premolars were endodontically treated. The specimens were randomly assigned into two groups according to different endodontic sealers. Group A used Endofil (eugenol-containing endodontic sealer), and group B used AH-plus (resin-containing endodontic sealer). After post space preparation, each group was randomly assigned into three subgroups according to the strategies of root canal irrigation (eight premolars in each subgroup). Group Al and B1: 0.9%NaCl irrigation; Group A2 and B2: 17% ethylene diamine tetraacetic acid (EDTA)+5.25%NaClO+0.9%NaCl irrigation; Group A3 and B3: ultrasonic agitation associated with 1 7%EDTA+5.25%NaClO+0.9%NaCl. One week after the cementation of fiber posts using RelyX™ Unicem, a push-out test was performed to measure the bond strength of the posts. The microstructure of the root canal surface was examined under scanning electron microscope (SEM).</p><p><b>RESULTS</b>The bond strengths of the six groups were as follows: Al (7.96±2.23) MPa, A2 (9.95±2.89) MPa, A3 (18.88±3.69) MPa, B1 (11.41±3.71) MPa, B2 (14.00±4.04) MPa, and B3 (19.14±3.27) MPa. Statistical analysis revealed a significant interaction between the different endodontic sealers and the strategies of root canal irrigation (P<0.05). Lower bond strength was found in group Al but not in group BI (P<0.05), and the same result was revealed when comparing group A2 and B2. No significant difference was observed between group A3 and B3 (P>0.05). SEM showed that the root canal in group A3 and B3 achieved the cleanest surface with nearly all dentine tubules opened.</p><p><b>CONCLUSION</b>The eugenol-containing endodontic sealer can impair the bond strength of fiber posts compared with the resin-containing sealer when the root canal is irrigated by 0.9% NaCl or 17%EDTA+5.25%NaClO+0.9%NaC. No difference was observed between the two sealers when using 17%EDTA+5.25% NaCIO+0.9%NaCl combined with ultrasonic irrigation.</p>


Assuntos
Humanos , Dente Pré-Molar , Cimentação , Colagem Dentária , Cavidade Pulpar , Análise do Estresse Dentário , Dentina , Técnica para Retentor Intrarradicular , Materiais Restauradores do Canal Radicular , Irrigantes do Canal Radicular , Tratamento do Canal Radicular
15.
Artigo em Chinês | WPRIM | ID: wpr-463550

RESUMO

Objective To investigate the correlation between the degree of liver fibrosis and Aspartate aminotransferase-to-Platelet Ratio Index ( APRI ) in children with biliary atresia ( BA ) , and evaluate the clinical significance of liver fibrosis in biliary atresia.Methods A total of 97 patients with diagnosed BA were recruited between January 2010 and June 2013.AST, PLT and APRI were determined one week before laparotomy.The severity of hepatic tibrosis was.Judged by Metavir system the correlation among AST, PLT, APRI and severity of liver fibrosis were evaluated, and their diagnostic value for degree of liver fibrosis was analyzed by ROC.Results Sera AST levels and PLT counts of BA patients were found to be positively(r=0.367, P<0.01) and negatively(r=-0.403, P<0.01) correlated with Metavir scores of liver fibrosis, respectively.There existed positive correlation between APRI and the severity of hepatic fibrosis (r=0.541, P<0.01).The area under ROC curve of APRI to diagnose none or mild fibrosis and moderately severe fibrosis was 0.78, with sensitivity of 77.9%and specificity of 62.1%at the optimal cut-off value of 0.75; the area under ROC curve of APRI to diagnose moderately severe fibrosis with liver cirrhosis arrived 0.85, with sensitivity of 75.0% and specificity of 89.4% at the optimal cut-off value of 1.77.The accuracy of none or mild fibrosis, moderate fibrosis and cirrhosis diagnosed by APRI were 73.2%, 64.9%, 87.6%, respectively.Conclusion APRI can be used as a non-invasive parameter to assess the severity of hepatic fibrosis with BA.

16.
Artigo em Chinês | WPRIM | ID: wpr-464132

RESUMO

Objective The alm of this study was to determine the solubility and permeability of daldzin and daldzein and the interaction of these two components.Methods With the method inChinese Pharmacopoeia and in situ single-pass intestinal perfusion model we tested the solubility and permeability of daldzin, daldzein and their interaction.Results In pH 7.4 K-R buffer the solubility of daldzin was 6 times than daldzein and both the solubility of these two components were enhanced when they were determined together. In small intestine of rat, the permeability of daldzein was 3 times than daldzin. Daldzin could enhance the permeability of daldzein but the daldzein manifested an opposite trend.Conclusion When compared to daldzin, daldzein owned a lower solubility but a better permeability. When used together, both the solubility and permeability of daldzein would be enhanced. The solubility of daldzin could be enhanced slightly but its permeability would be reduced.

17.
Artigo em Chinês | WPRIM | ID: wpr-317807

RESUMO

<p><b>OBJECTIVE</b>To evaluate the effect of different auxiliary resistance forms on the resistance and marginal fitness of complete crowns for short molar preparations.</p><p><b>METHODS</b>A total of 70 Nissin resin teeth were prepared with 20° total occlusal convergence, 2.5 mm of occlusocervical height, and a shallow finish line on a milling machine. The milled preparations were then randomly assigned to 7 groups of 10. The first group was used as the control group. A total of 30 dies were modified by preparing interproximal grooves with angles of 0°, 6°, and 20° centered on the mesial and distal surfaces of the dies. The rest of the teeth were prepared with occlusal holes in the center of the occlusal surface milled with the same burs to form 0°, 6°, and 20° holes. Cobalt-chromium copings were fabricated for all specimens. The marginal gap of specific points on the axial surface was measured before and after cementation. The resistance of each specimen was evaluated by applying an external force at an angle of 45° to the long axis of the die by using a universal testing machine in a lingual to buccal direction. The maximum force applied before crown dislodgement was measured. Data were analyzed using the SAS 9.2 software.</p><p><b>RESULTS</b>The results showed that the 0° groove, 0° hole, and 6° hole were effective in improving the resistance of the complete crowns (P<0.05). The 0° groove, 6° groove, 0° hole, 6° hole, and 20° hole had significant difference with the control group in terms of marginal discrepancies (P<0.05).</p><p><b>CONCLUSION</b>Auxiliary resistance forms with less degree indicate greater resistance force but worse marginal fitness. In clinical practice, if the resistance of a preparation is enough, the auxiliary resistance forms should be avoided from being used.</p>


Assuntos
Humanos , Cimentação , Coroas , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Dente Molar , Coroa do Dente
18.
Artigo em Chinês | WPRIM | ID: wpr-451356

RESUMO

Objective To investigate the effects of Kr üppel-like factor 2 ( KLF2 ) on oxidized low density lipoprotein (ox-LDL) induced expression of microRNA-146a (miR-146a) and proinflammatory cyto-kines (MCP-1 and IL-6) in human umbilical vein endothelial cells (HUVECs).Methods Human umbili-cal vein endothelial cells (HUVECs) were cultured and then stimulated with 50μg/ml ox-LDL for 24 hours. HUVECs were infected with adenovirus vectors over-expressing human KLF2 at an appropriate multiplicity of infection.KLF2-siRNA duplexes were transfected into HUVECs to silence the gene expression .HUVECs were collected at time points of 0 h, 3 h, 6 h, 12 h, 24 h and 48 h after infection.Real-time quantitative-PCR was performed to measure the expression of miR-146a at mRNA level.Silenced endogenous miR-146a using LNA-anti-miR-146 a was transfected into HUVECs with lipofectamine 2000 .The levels of MCP-1 and IL-6 in supernatants were detected by ELISA .Results KLF2 remarkably inhibited the expression of miR-146 a in unstimulated and ox-LDL-stimulated HUVECs in a time-dependent manner .The ox-LDL induced ex-pression of miR-146a, MCP-1 and IL-6 in HUVECs were significantly decreased by KLF2.Silenced expres-sion of miR-146a downr-egulated the ox -LDL induced expression of MCP-1 and IL-6 in HUVECs.Moreover, silenced miR-146 a could partly reverse the inhibitory effects of KLF 2 on ox-LDL induced expression of MCP-1 and IL-6 in HUVECs.Conclusion KLF2 inhibited ox-LDL induced expression of MCP-1 and IL-6 in HUVECs partly through down-regulating the expression of miR-146a.

19.
Acta Anatomica Sinica ; (6): 551-554, 2009.
Artigo em Chinês | WPRIM | ID: wpr-405943

RESUMO

Objective To investigate the expression of Nogo-A in the retinal ganglion cells (RGCs) and their axons of mouse embryos and its time course changes. Methods Sections of retinofugal pathway of C57 mouse embryos at different developmental stages were immunostained with Nogo-A specific antibody and observed by a confocal microscopy. The identity of Nogo-A positive cells was partially revealed by double-staining together with Tuj-1. Results At the early stage of E12, Nogo-A was densely expressed in some radially-orientated cells in retina. The immunopositive signals appeared in the cytoplasm, on the cell membrane and axons. The double-labeling together with Tuj-1, a neuronal marker, showed that nearly all the RGCs and their axons expressed Nogo-A protein. At the later stage of E13, the number of Nogo-A positive neurons in retina decreased dramatically. And those Nogo-A positive RGCs were specifically located in the ventricular part and the ciliary margin zone of the retina. At this stage, only a very few axons maintained their Nogo-A expression in the fiber layer of the retina, while most lost their Nogo-A distribution. When most RGCs had fully differentiated at E15, there was no detectable Nogo-A immunopositive staining in the retina and only a few retinal fibers were Nogo-A immunopositive. The similar expression patterns of Nogo-A was found in a few axons along the optic disc, optic stalk, optic chiasm and optic tract. Worthy of note, the retinal axons with Nogo-A distribution in the optic tract were exclusively found in the superficial area, where the newly-arrived axons were traveling through during development. Conclusion The expression pattern and its time course change suggested that Nogo-A was an important protein expressed by the newly differentiated RGC neurons and their projecting axons, whilst the mature RGCs down-regulated their expression. Nogo-A in the new born RGCs might play some cell-intrinsic roles such as decreasing axon branching in vivo.

20.
Artigo em Chinês | WPRIM | ID: wpr-409414

RESUMO

BACKGROUND: The environmental change of regeneration of peripheral nerve fiber can accelerate the regeneration of nerve fiber and the recovery of nerve function. Physiotherapy can improve the local microcirculation of the injured area, and promote and stimulate the recovery course of trauma. Therefore, whether choosing different physiotherapies and controlling irradiation dose can speed up the regeneration of nerve fiber?OBJECTIVE: To observe the effects of different physiotherapies in promoting the regeneration of injured nerve fiber.DESIGN:Randomized grouping and controlled animal experiment.SETTING: Laboratory of Anthropotomy and Histo-Embryology Department,Peking University Health Science Center.MATERIALS: The experiment was conducted in the Laboratory of Anthropotomy and Histo-Embryology Department, Peking University Health Science Center, from September 2001 to September 2002. Fifteen adult male SD rats, weighting 185-220 g, were selected.INTERVENTIONS: The model of sciatic nerve injury was established and randomly assigned to 3 groups. Bio-spectrum group and infrared group with 5rats in each received the corresponding physical irradiation. Injury control group was given no irradiation. The slices of sciatic nerve at the operation side of the animals in the three groups were collected on day 14 after operation. The degeneration rate of the injured nerve fiber was observed under the optical microscope to make indirect assessment of the protective effect of physiotherapy after the nerve was injured.MAIN OUTCOME MEASURES: The degeneration rate of nerve fibers at the breakpoint and at 4 points near the spinal cord ( 1,2,3,4 mm) and away from the spinal cord( 1,2,3,4 mm).difference in the degeneration rate of nerve fibers at the breakpoint away from the spinal cord in bio-spectrum group and infrared group as compared with the degeneration rate of nerve fibers in bio-spectrum group(68% ) and infrared group(89% ) was obviously reduced and that in control group was the the spinal cord in the 3 groups showed decreasing trend: the closer to the spinal cord, the fewer the degenerative nerve fibers. The number of degenerative nerve fibers was the smallest in bio-spectrum group, second smallest in infrared group, and the largest in control group.CONCLUSION: The assisting physiotherapy can decrease the number of regenerative nerve fibers, thus promoting and accelerating their recovery. Irradiation with bio-spectrum equipment is more effective.

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