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1.
J Pharm Biomed Anal ; 240: 115924, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38142499

ABSTRACT

The quality standards for Andrographis paniculata, a widely used medicinal herb, exhibited significant variations across different pharmacopeias. In this study, we compared the HPLC content determination methods and total lactone content of A. paniculata samples from different regions, as specified in the Chinese (CP), United States (USP), European (EP), Thai (TP), and Indian pharmacopeias (IP), as well as the Hong Kong Chinese Materia Medica Standards (HK). We aimed to assess the differences and similarities among these pharmacopeias and harmonized international quality standards for A. paniculata. The analysis revealed variations in sample preparation, liquid chromatographic conditions, fingerprint profiles, and total lactone content among the different pharmacopeias. Specifically, the CP and HK methods exhibited superior sample preparation and chromatographic separation. Further comparing the content of 20 A. paniculata samples with the CP, USP, EP and HK methods showed consistent determinations for the same components, indicating similar detection capabilities. The discrepancies in total lactone content primarily stemmed from differences in the number and types of detected compounds. Moreover, the acceptance criteria exhibited a stringency in the order CP > HK > EP > USP. In conclusion, this comparison analysis of content determination in CP, USP, HK, EP, TP and IP provided a scientific foundation for the international standardization and trade regulations of A. paniculata. It also served as a valuable reference for the development of international quality standards for other medicinal herbs, facilitating the harmonization of global pharmaceutical standards.


Subject(s)
Andrographis , Diterpenes , Plants, Medicinal , Andrographis paniculata , Andrographis/chemistry , Diterpenes/analysis , Plants, Medicinal/chemistry , Lactones , Reference Standards , Plant Extracts/chemistry
2.
J Org Chem ; 88(20): 14445-14453, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37815929

ABSTRACT

The direct alkoxylation of amides has been accomplished via methoxyiminoacyl (MIA)-mediated Pd-catalyzed C-H functionalization. A diverse array of alkylamide substrates is amenable to this protocol, providing γ-C(sp3)-alkoxylation of alkylamide derivatives with good to high efficiency. Two aspects of the research were completed to explore the reaction mechanism. On the one hand, the result of the kinetic isotopic effect experiment and control experiment indicated that reductive elimination is a rate-limiting step. On the other hand, density functional theory calculations demonstrated that a concerted Sn2 reductive elimination mechanism pathway is prior. Finally, the MIA group could be efficiently hydrogenated and protected in a one-pot procedure, which provides a short synthetic route to γ-methoxy amino acid derivatives.

3.
Chin J Dent Res ; 26(2): 113-117, 2023 06 23.
Article in English | MEDLINE | ID: mdl-37395523

ABSTRACT

Implant-retained removable partial dentures (RPDs) are commonly used to resolve the complications associated with traditional distal extension RPDs; however, this technology does not consider the necessity and importance of parallelism between the path of RPD insertion and the long axis of the implant. This clinical report presents a novel digital preparation technique that involves the preparation of parallel guiding planes on abutment teeth and implant insertion in the distal extension area using a computer-aided design and manufacturing template. This clinical case of implant-retained RPDs illustrates the fabrication and application of the digital template. Using this technique, the path of RPD insertion is parallel to the long axis of the implant. As a result, the components of the implant-retained RPD, including the abutment teeth, implants and attachments, can demonstrate greater longevity.


Subject(s)
Denture, Partial, Removable , Tooth , Humans , Face , Computer-Aided Design , Technology
4.
Asia Pac J Clin Nutr ; 32(1): 33-39, 2023.
Article in English | MEDLINE | ID: mdl-36997483

ABSTRACT

BACKGROUND AND OBJECTIVES: Observational studies have shown that energy restriction could be beneficial for controlling bodyweight in patients with polycystic ovary syndrome (PCOS). We aim to compare the effects of a high-protein diet (HPD), a high-protein and high-dietary fiber diet (HPHFD), and a calorie-restricted diet (CRD) on metabolic health and gut microbiota in overweight/obese PCOS patients. METHODS AND STUDY DESIGN: We will enroll a total of 90 overweight/obese PCOS patients into this eight-week open-label randomised controlled trial. Participants will be randomly assigned to three groups: CRD group (energy coefficient 20 kcal/kg.day, water ≥1500 mL, 0.8-1.2 g/kg protein, carbohydrate energize 55-60%, and fat energize 25-30%), HDP group (energy coefficient 20 kcal/kg.day, water ≥1500 mL, and 1.5-2.0 g/kg protein) and HPHFD group (based on the high protein diet with 15 g more dietary fiber supplement). The primary outcome is body weight, body fat percentage, and lean body mass. The secondary outcomes will include changes in blood lipids, inflammation, glucose tolerance, blood pressure, and gut microbiota compositions. Between-group differences in adiposity measurements at baseline will be compared using one-way analysis of variance (ANOVA) or Kruskal-Wallis test when appropriate. Within-group difference after 8-week intervention will be compared using paired t-test or Wilcoxon signed rank test. Between-group differences in adiposity measurements after 8-week diet intervention will be compared using linear mixed model and ANCOVA. The gut microbiota will be analyzed using 16S amplicon sequencing and the sequencing data will be analyzed using the standardized QIIME2 piperline.


Subject(s)
Gastrointestinal Microbiome , Insulin Resistance , Polycystic Ovary Syndrome , Female , Humans , Overweight/complications , Overweight/therapy , Polycystic Ovary Syndrome/complications , Polycystic Ovary Syndrome/therapy , Weight Loss , Obesity/complications , Obesity/therapy , Body Weight , Dietary Fiber , Randomized Controlled Trials as Topic
5.
Metabolites ; 12(4)2022 Mar 25.
Article in English | MEDLINE | ID: mdl-35448474

ABSTRACT

This study centered on detecting potentially anti-inflammatory active constituents in ethanolic extracts of Chinese Lonicera species by taking an UHPLC-HRMS-based metabolite profiling approach. Extracts from eight different Lonicera species were subjected to both UHPLC-HRMS analysis and to pharmacological testing in three different cellular inflammation-related assays. Compounds exhibiting high correlations in orthogonal projections to latent structures discriminant analysis (OPLS-DA) of pharmacological and MS data served as potentially activity-related candidates. Of these candidates, 65 were tentatively or unambiguously annotated. 7-Hydroxy-5,3',4',5'-tetramethoxyflavone and three bioflavonoids, as well as three C32- and one C34-acetylated polyhydroxy fatty acid, were isolated from Lonicera hypoglauca leaves for the first time, and their structures were fully or partially elucidated. Of the potentially active candidate compounds, 15 were subsequently subjected to pharmacological testing. Their activities could be experimentally verified in part, emphasizing the relevance of Lonicera species as a source of anti-inflammatory active constituents. However, some compounds also impaired the cell viability. Overall, the approach was found useful to narrow down the number of potentially bioactive constituents in the complex extracts investigated. In the future, the application of more refined concepts, such as extract prefractionation combined with bio-chemometrics, may help to further enhance the reliability of candidate selection.

6.
Front Plant Sci ; 12: 681490, 2021.
Article in English | MEDLINE | ID: mdl-34567020

ABSTRACT

Crop plants grow, and then, they allocate resources to different structures, including seeds and fruits, which represent yield in most crops. We define the yield stability of a genotype as its ability to reduce the effects of temporal variation in resources and conditions on yield production, and we argue that yield stability can be understood in terms of two processes: (1) crop survival and growth (biomass production): the ability of the crop plants to survive and produce biomass under the range of conditions to which it is exposed and (2) the pattern of allocation of this biomass to yield across this range of conditions. Plant breeders and crop physiologists have focused on (1), but much less attention has been paid to (2). We hypothesize that (2) is primarily the result of reproductive allometry: the quantitative relationship between vegetative and reproductive biomass. Ecological theory and the allometric models we present predict a tradeoff between (a) the ability of a genotype to produce yield over a wide variety of conditions and (b) its ability to produce very high yields under optimal or near-optimal conditions. We reanalyze the data from two recent studies, and the results are consistent with this hypothesis. Yield stability in crops corresponds to bet-hedging in evolutionary ecological theory. It is the most appropriate strategy for smallholder farmers in developing countries, a group that comprises most of the farmers in the world. Researchers and crop breeders need to rethink their objectives if they want to develop optimal varieties for these farmers.

7.
Front Plant Sci ; 11: 532537, 2020.
Article in English | MEDLINE | ID: mdl-33584738

ABSTRACT

Allocation dynamics of stored starch plays essential roles in the development and growth of trees. Previous studies focused on the dynamics and the characteristics of starch in autotrophic trees. However, although starch granules have been detected in the organs or tissues of some parasitic plants, studies on the allocation dynamics and roles of storage starch in them are limited. Therefore, we determined and estimated the allocation dynamics and roles of starch in Santalum album Linn., a hemiparasitic tree, using morphological and physiological methods. Our findings showed abundant starch in the stem and root of S. album at the early seedling stage. Although S. album seedlings attached to the host showed no significant changes in starch levels throughout the experiment, unattached and host-removed seedlings exhibited a gradual decrease in the starch content over time. When the starch content of unattached seedlings was less than 1%, they started to die. Starch accumulated to high levels in developing and active haustoria; however, starch levels were low in the inactive haustoria. The present study suggests that starch may provide energy to seedlings that have no host, allowing them to survive during the unattached phase, thus increasing their chance to attach to host roots by extending their survival duration. In addition, we speculate that storage starch is potentially involved in the development of haustoria and in the physiological processes of S. album related to the absorption and transportation of water and nutrients from its host.

8.
Int J Comput Dent ; 22(3): 251-260, 2019.
Article in English | MEDLINE | ID: mdl-31463489

ABSTRACT

The application of robots in oral treatment can not only reduce the work intensity of clinicians but also improve the accuracy of treatment. In this article, the application and research status of robots in stomatology are reviewed.


Subject(s)
Oral Medicine , Robotics , Humans
9.
Sci Rep ; 6: 28126, 2016 06 21.
Article in English | MEDLINE | ID: mdl-27324079

ABSTRACT

Periodontal regeneration involves the restoration of at least three unique tissues: cementum, periodontal ligament tissue (PDL) and alveolar bone tissue. Here, we first isolated human PDL stem cells (PDLSCs) and jaw bone mesenchymal stem cells (JBMSCs). These cells were then induced to form cell sheets using an ascorbic acid-rich approach, and the cell sheet properties, including morphology, thickness and gene expression profile, were compared. Platelet-rich fibrin (PRF) derived from human venous blood was then fabricated into bioabsorbable fibrin scaffolds containing various growth factors. Finally, the in vivo potential of a cell-material construct based on PDLSC sheets, PRF scaffolds and JBMSC sheets to form periodontal tissue was assessed in a nude mouse model. In this model, PDLSC sheet/PRF/JBMSC sheet composites were placed in a simulated periodontal space comprising human treated dentin matrix (TDM) and hydroxyapatite (HA)/tricalcium phosphate (TCP) frameworks. Eight weeks after implantation, the PDLSC sheets tended to develop into PDL-like tissues, while the JBMSC sheets tended to produce predominantly bone-like tissues. In addition, the PDLSC sheet/PRF/JBMSC sheet composites generated periodontal tissue-like structures containing PDL- and bone-like tissues. Further improvements in this cell transplantation design may have the potential to provide an effective approach for future periodontal tissue regeneration.


Subject(s)
Guided Tissue Regeneration, Periodontal , Mandible/surgery , Maxilla/surgery , Mesenchymal Stem Cell Transplantation , Periodontal Ligament/surgery , Periodontitis/therapy , Platelet-Rich Fibrin/metabolism , Adolescent , Adult , Animals , Calcium Phosphates , Cell Differentiation , Cells, Cultured , Dentin , Humans , Male , Mandible/physiology , Maxilla/physiology , Mesenchymal Stem Cells/cytology , Mice , Mice, Nude , Osteogenesis , Periodontal Ligament/physiology , Periodontitis/surgery , Tissue Engineering , Tissue Scaffolds/chemistry , Young Adult
10.
Shanghai Kou Qiang Yi Xue ; 24(5): 551-6, 2015 Oct.
Article in Chinese | MEDLINE | ID: mdl-26598187

ABSTRACT

PURPOSE: This study was intended to modify the surface of pure titanium by micro-arc oxidation (MAO), and to investigate the effects of MAO process on the biological behavior of MC3T3-E1 osteoblastic cells. METHODS: MAO treatment of specimens were carried out using a staggered voltage boost procedure. The surface topography of the prepared specimens were observed by field emission scanning electron microscopy. Contact angle measurements were tested on a contact angle measuring system. MC3T3-E1 cells were cultured on specimens and the number of adhesion cells at 60 and 120 min were investigated by MTT. After 4 h of culture, cytoskeleton of the attached cells were examined using laser confocal scanning microscope. After 24, 72, 120 and 168 h of post seeding, cell proliferation were assessed using MTT assay. On day 16 of culture, the expressions of osteogenesis-related genes were analyzed through real time fluorescence quantitative polymerase chain reaction (qPCR). The data was analyzed using SPSS 16.0 software package. RESULTS: A porous oxide layer was grown on pure titanium substrates via MAO process. The contact angles for water and glycerol on the MAO surface were smaller than polished surface. At 2 culture times, the MAO surface showed significantly higher cell adhesion than polished surface. Actin staining indicated that the cells spread well on the MAO surface. At 72, 120 and 168 h, better cell proliferation were seen for MAO surfaces compared with that on the polished surface, but there was no significant difference. The qPCR showed that no obvious variations in gene expression of RUNX2 and ALP by MC3T3-E1 cells were observed on 2 different surfaces. CONCLUSIONS: Compared with polished surface, better adhesion of MC3T3-E1 cells are observed on MAO surface. However, no obvious change in gene expression of RUNX2 and ALP were observed between the MAO surface and polished surface.


Subject(s)
Osteoblasts/physiology , Titanium , Animals , Cell Adhesion , Cell Line , Cell Proliferation , Gene Expression , Mice , Microscopy, Electron, Scanning , Osteogenesis , Oxidation-Reduction , Real-Time Polymerase Chain Reaction , Surface Properties
11.
Molecules ; 20(5): 8107-24, 2015 May 05.
Article in English | MEDLINE | ID: mdl-25951006

ABSTRACT

A high-performance liquid chromatography coupled with quadrupole tandem time-of-flight mass (HPLC-QTOF-MS) and ultraviolet spectrometry (HPLC-UV) was established for simultaneous qualitative and quantitative analysis of the major chemical constituents in Caulis Trachelospermi, respectively. The analysis was performed on an Agilent Zorbax Eclipse Plus C18 column (4.6 mm×150 mm, 5 µm) using a binary gradient system of water and methanol, with ultraviolet absorption at 230 nm. Based on high-resolution ESI-MS/MS fragmentation behaviors of the reference standards, the characteristic cleavage patterns of lignano-9, 9'-lactones and lignano-8'-hydroxy-9, 9'-lactones were obtained. The results demonstrated that the characteristic fragmentation patterns are valuable for identifying and differentiating lignano-9,9'-lactones and lignano-8'-hydroxy-9,9'-lactones. As such, a total of 25 compounds in Caulis Trachelospermi were unambiguously or tentatively identified via comparisons with reference standards or literature. In addition, 14 dibenzylbutyrolatone lignans were simultaneously quantified in Caulis Trachelospermi by HPLC-UV method. The method is suitable for the qualitative and quantitative analyses of dibenzylbutyrolatone lignans in Caulis Trachelospermi.


Subject(s)
Drugs, Chinese Herbal/chemistry , Lignans/chemistry , Plant Extracts/chemistry , Chromatography, High Pressure Liquid/methods , Lactones/chemistry , Medicine, Chinese Traditional/methods , Reference Standards , Spectrophotometry, Ultraviolet/methods , Tandem Mass Spectrometry/methods
12.
J Pediatr ; 166(2): 326-31.e2, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25491091

ABSTRACT

OBJECTIVE: To examine the association between the timing and type of complementary feeding and childhood adiposity in Mainland China. STUDY DESIGN: During 1999-2009, 97 424 singletons were enrolled in the Jiaxing Birth Cohort, a population-based prospective cohort study in Southeast China. Of these children, 43 848 children provided complementary diet information and other anthropometric measurements at 1, 3, and 6 months of age and were followed up until 4-5 years of age. Obesity and overweight were identified as body mass index (BMI)-for-age z-score (SD) ≥2 and between 1 and 2, respectively. RESULTS: Among 40 510 children in the statistical analysis, 3.18% were overweight and 64.8% were fed complementary food before 3 months of age. Early introduction of complementary foods was associated with greater BMI z-score (P-trend < .001) and higher risk of overweight (P-trend = .033). Compared with introduction of complementary foods between 4-6 months of age, before 3 months of age of introduction was associated with 11% greater risk of overweight (OR 1.11, 95% CI 1.03-1.19). No significant association between timing of complementary feeding and obesity was observed. Fish liver oil was the major type of complementary food associated with adiposity. Early introduction of fish liver oil was associated with greater BMI z-score (P < .001) and greater risk of overweight (P-trend = .004). CONCLUSIONS: Early introduction of fish liver oil is associated with greater childhood BMI and risk of overweight in Chinese children at 4-5 years of age.


Subject(s)
Adiposity , Body Mass Index , Infant Nutritional Physiological Phenomena , Age Factors , Child, Preschool , China , Cohort Studies , Female , Humans , Infant , Male , Overweight/epidemiology , Pediatric Obesity/epidemiology , Prospective Studies , Risk Assessment
13.
Molecules ; 19(8): 11560-71, 2014 Aug 05.
Article in English | MEDLINE | ID: mdl-25100250

ABSTRACT

Initial investigation for new active herbal extract with inhibiting activity on JAK/STAT signaling pathway revealed that the extract of Caulis Trachelospermi, which was separated by 80% alcohol extraction and subsequent HP-20 macroporous resin column chromatography, was founded to strongly inhibit IFN-γ-induced STAT1-responsive luciferase activity (IFN-γ/STAT1) with IC50 value of 2.43 µg/mL as well as inhibiting IL-6-induced STAT3-responsive luciferase activity (IL-6/STAT3) with IC50 value of 1.38 µg/mL. Subsequent study on its active components led to the isolation and identification of two new dibenzylbutyrolactone lignans named 4-demethyltraxillaside (1) and nortrachelogenin 4-O-ß-D-glucopyranoside (2), together with six known compounds. The lignan compounds 1-4 together with other lignan compounds isolated in previous study were tested the activities on IFN-γ/STAT1 and IL-6/STAT3 pathways. The following result showed that the main components trachelogenin and arctigenin had corresponding activities on IFN-γ/STAT1 pathway with IC50 values of 3.14 µM and 9.46 µM as well as trachelogenin, arctigenin and matairesinol strongly inhibiting IL-6/STAT3 pathway with IC50 values of 3.63 µM, 6.47 µM and 2.92 µM, respectively.


Subject(s)
Plant Extracts/pharmacology , Signal Transduction/drug effects , Tracheophyta/chemistry , Cell Line, Tumor , Humans , Inhibitory Concentration 50 , Interferon-gamma/metabolism , Interleukin-6/metabolism , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Plant Extracts/chemistry , STAT1 Transcription Factor/metabolism , STAT3 Transcription Factor/metabolism
14.
J Nutr ; 144(9): 1454-9, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25008581

ABSTRACT

The association between breastfeeding status and childhood overweight is inconclusive. The aim of the present study was to investigate the relation between exclusive breastfeeding and childhood overweight risk in children 4-5 y of age in Southeast China. Among 97,424 children enrolled between 1999 and 2009 in the Jiaxing Birth Cohort, 42,550 of them were included in the final analysis with complete records on breastfeeding status and anthropometric measurements at 4-5 y of age (48-60 mo). Overweight and being at risk of overweight were identified as a body mass index (BMI)-for-age Z-score ≥ 2 and between 1 and 2, respectively. After 4-5 y of follow-up, 4845 (11.4%) children were identified as being at risk of overweight, and 1343 (3.16%) children were overweight. Adjusting for important child and maternal characteristics, longer duration of breastfeeding was associated with lower risk of childhood overweight (P-trend = 0.009) and being at risk of overweight (P-trend < 0.001). Children exclusively breastfed for 3-5 mo and ≥6 mo had 13% (RR = 0.87; 95% CI: 0.77, 0.99) and 27% (RR = 0.73; 95% CI: 0.56, 0.95) lower risk of becoming overweight compared with children exclusively breastfed for <1 mo, respectively. In boys, there were inverse associations of 3-5 mo (RR = 0.83; 95% CI: 0.71, 0.98) or ≥6 mo (RR = 0.65; 95% CI: 0.47, 0.91) of exclusive breastfeeding against becoming overweight, but there were no significant associations in girls (3-5 mo: RR = 0.96, 95% CI: 0.76, 1.22; ≥6 mo: RR = 0.92, 95% CI: 0.60, 1.41). In conclusion, the present findings suggest that longer duration of exclusive breastfeeding is associated with lower risk of becoming overweight in Chinese children.


Subject(s)
Body Mass Index , Breast Feeding , Pediatric Obesity/prevention & control , Child, Preschool , China , Cohort Studies , Female , Humans , Infant , Infant, Newborn , Male , Overweight/prevention & control , Risk , Sex Factors
15.
BMJ ; 346: f3706, 2013 Jun 27.
Article in English | MEDLINE | ID: mdl-23814120

ABSTRACT

OBJECTIVES: To investigate the association between intake of fish and n-3 polyunsaturated fatty acids (n-3 PUFA) and the risk of breast cancer and to evaluate the potential dose-response relation. DESIGN: Meta-analysis and systematic review of prospective cohort studies. DATA SOURCES: PubMed and Embase up to December 2012 and references of retrieved relevant articles. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Prospective cohort studies with relative risk and 95% confidence intervals for breast cancer according to fish intake, n-3 PUFA intake, or tissue biomarkers. RESULTS: Twenty six publications, including 20,905 cases of breast cancer and 883,585 participants from 21 independent prospective cohort studies were eligible. Eleven articles (13,323 breast cancer events and 687,770 participants) investigated fish intake, 17 articles investigated marine n-3 PUFA (16,178 breast cancer events and 527,392 participants), and 12 articles investigated alpha linolenic acid (14,284 breast cancer events and 405,592 participants). Marine n-3 PUFA was associated with 14% reduction of risk of breast cancer (relative risk for highest v lowest category 0.86 (95% confidence interval 0.78 to 0.94), I(2)=54), and the relative risk remained similar whether marine n-3 PUFA was measured as dietary intake (0.85, 0.76 to 0.96, I(2)=67%) or as tissue biomarkers (0.86, 0.71 to 1.03, I(2)=8%). Subgroup analyses also indicated that the inverse association between marine n-3 PUFA and risk was more evident in studies that did not adjust for body mass index (BMI) (0.74, 0.64 to 0.86, I(2)=0) than in studies that did adjust for BMI (0.90, 0.80 to 1.01, I(2)=63.2%). Dose-response analysis indicated that risk of breast cancer was reduced by 5% per 0.1g/day (0.95, 0.90 to 1.00, I(2)=52%) or 0.1% energy/day (0.95, 0.90 to 1.00, I(2)=79%) increment of dietary marine n-3 PUFA intake. No significant association was observed for fish intake or exposure to alpha linolenic acid. CONCLUSIONS: Higher consumption of dietary marine n-3 PUFA is associated with a lower risk of breast cancer. The associations of fish and alpha linolenic acid intake with risk warrant further investigation of prospective cohort studies. These findings could have public health implications with regard to prevention of breast cancer through dietary and lifestyle interventions.


Subject(s)
Breast Neoplasms/epidemiology , Fatty Acids, Omega-3/administration & dosage , Seafood/statistics & numerical data , alpha-Linolenic Acid/metabolism , Body Mass Index , Female , Humans , Prospective Studies , Risk Factors
16.
Yao Xue Xue Bao ; 48(5): 718-22, 2013 May.
Article in Chinese | MEDLINE | ID: mdl-23888695

ABSTRACT

Angelica polymorpha Maxim. is a plant of the Angelica genus (Umbelliferae). The root and stem of this plant is a folk medicine known to have the actions of relieving rheumatism and cold and subsiding swelling and pains. To investigate the chemical constituents in the root of A. polymorpha Maxim., seven compounds were isolated from an 80% ethanol extract by column chromatography. Their structures were elucidated according to the spectroscopic analysis. Compound 1 is a new sesquiterpene, named as bisabolactone. Its absolute configuration was determined by 1D NOESY and CD analysis. The others were identified as 5-hydroxymethylfurfural (2), hycandinic acid ester 1 (3), ferulic acid (4), isooxypeucedanin (5), noreugenin (6) and cimifugin (7). Compound 2 and 3 were isolated from this genus for the first time and compound 4 was isolated from this plant for the first time.


Subject(s)
Angelica/chemistry , Plants, Medicinal/chemistry , Sesquiterpenes/isolation & purification , Chromones/chemistry , Chromones/isolation & purification , Coumaric Acids/chemistry , Coumaric Acids/isolation & purification , Coumarins/chemistry , Coumarins/isolation & purification , Furaldehyde/analogs & derivatives , Furaldehyde/chemistry , Furaldehyde/isolation & purification , Molecular Structure , Plant Roots/chemistry , Quinic Acid/analogs & derivatives , Quinic Acid/chemistry , Quinic Acid/isolation & purification , Sesquiterpenes/chemistry
17.
Chin Med J (Engl) ; 126(5): 879-83, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23489795

ABSTRACT

BACKGROUND: Varieties of restorative materials are widely used in dentistry. The aim of this study is to explore the influence of different dental restorative materials on bond interface reliability. METHODS: A two-dimensional finite element analysis method was adopted to simulate the shear-bond efficacy test. The influence of elastic modulus and Poisson's ratio were investigated separately. Several dental restorative materials including resins, metals, and ceramics were analyzed in this study. RESULTS: The deformation and peak equivalent stress level of the dentin-adhesive interface rose sharply following a decrease in the elasticity of restorative materials, especially those with a low elastic modulus range. The influence of the Poisson's coefficient was not significant. Ceramics and gold alloy were preferred to resin composite in restorations bearing extensive shear load during service. CONCLUSIONS: Restorative materials with an elastic modulus similar to that of teeth are not always the best clinical choice. This research provides a helpful guide for the application of different restorative materials in clinical practice.


Subject(s)
Dental Bonding , Dental Materials , Finite Element Analysis , Humans
18.
Cell Transplant ; 22(2): 205-29, 2013.
Article in English | MEDLINE | ID: mdl-23031442

ABSTRACT

Stem cells have received a great deal of interest from the research community as potential therapeutic "tools" for a variety of chronic debilitating diseases that lack clinically effective therapies. Stem cells are also of interest for the regeneration of tooth-supporting tissues that have been lost to periodontal disease. Indeed, substantial data have demonstrated that the exogenous administration of stem cells or their derivatives in preclinical animal models of periodontal defects can restore damaged tissues to their original form and function. As we discuss here, however, considerable hurdles must be overcome before these findings can be responsibly translated to novel clinical therapies. Generally, the application of stem cells for periodontal therapy in clinics will not be realized until the best cell(s) to use, the optimal dose, and an effective mode of administration are identified. In particular, we need to better understand the mechanisms of action of stem cells after transplantation in the periodontium and to learn how to preciously control stem cell fates in the pathological environment around a tooth. From a translational perspective, we outline the challenges that may vary across preclinical models for the evaluation of stem cell therapy in situations that require periodontal reconstruction and the safety issues that are related to clinical applications of human stem cells. Although clinical trials that use autologous periodontal ligament stem cells have been approved and have already been initiated, proper consideration of the technical, safety, and regulatory concerns may facilitate, rather than inhibit, the clinical translation of new therapies.


Subject(s)
Periodontal Diseases/therapy , Periodontium/physiology , Periodontium/transplantation , Regenerative Medicine/methods , Stem Cell Transplantation/methods , Animals , Humans , Periodontium/drug effects , Regenerative Medicine/trends , Stem Cell Transplantation/trends , Translational Research, Biomedical
19.
Biotechnol Adv ; 30(3): 658-72, 2012.
Article in English | MEDLINE | ID: mdl-22138411

ABSTRACT

Translational medicine is an evolutional concept that encompasses the rapid translation of basic research for use in clinical disease diagnosis, prevention and treatment. It follows the idea "from bench to bedside and back", and hence relies on cooperation between laboratory research and clinical care. In the past decade, translational medicine has received unprecedented attention from scientists and clinicians and its fundamental principles have penetrated throughout biomedicine, offering a sign post that guides modern medical research toward a patient-centered focus. Translational regenerative medicine is still in its infancy, and significant basic research investment has not yet achieved satisfactory clinical outcomes for patients. In particular, there are many challenges associated with the use of cell- and tissue-based products for clinical therapies. This review summarizes the transformation and global progress in translational medicine over the past decade. The current obstacles and opportunities in translational regenerative medicine are outlined in the context of stem cell therapy and tissue engineering for the safe and effective regeneration of functional tissue. This review highlights the requirement for multi-disciplinary and inter-disciplinary cooperation to ensure the development of the best possible regenerative therapies within the shortest timeframe possible for the greatest patient benefit.


Subject(s)
Dentistry/methods , Regenerative Medicine/trends , Stem Cell Transplantation/methods , Translational Research, Biomedical/trends , Biomedical Research/trends , Dentistry/trends , Humans , Precision Medicine/trends , Regenerative Medicine/methods , Stem Cell Transplantation/trends , Tissue Engineering/methods
20.
J Mater Sci Mater Med ; 23(3): 853-62, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22201031

ABSTRACT

Since calcium phosphates (CaPs) were first proposed, a wide variety of formulations have been developed and continuously optimized, some of which (e.g. calcium phosphate cements, CPCs) have been successfully commercialized for clinical applications. These CaP-based biomaterials have been shown to be very attractive bone substitutes and efficient drug delivery vehicles across diverse biomedical applications. In this article, CaP biomaterials, principally CPCs, are addressed as alternatives/complements to autogenous bone for grafting in implant dentistry and as coating materials for enhancing the osteoinductivity of titanium implants, highlighting their performance benefits simultaneously as carriers for growth factors and as scaffolds for cell proliferation, differentiation and penetration. Different strategies for employing CaP biomaterials in dental implantology aim to ultimately reach the same goal, namely to enhance the osseointegration process for dental implants in the context of immediate loading and to augment the formation of surrounding bone to guarantee long-term success.


Subject(s)
Biocompatible Materials , Calcium Phosphates/chemistry , Dental Implants
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