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1.
Zhongguo Zhong Yao Za Zhi ; 45(8): 1859-1865, 2020 Apr.
Artículo en Zh | MEDLINE | ID: mdl-32489070

RESUMEN

The historical preparation methods of Glycyrrhizae Radix et Rhizoma were summarized and analyzed by consulting relevant literatures of herbal medicines and medical classics. This study also reviewed the records of Glycyrrhizae Radix et Rhizoma processing methods in previous editions of the Chinese Pharmacopoeia and the regulations on processing technology of Glycyrrhizae Radix et Rhizoma decoction pieces in China. This paper summarized the processing history of Glycyrrhizae Radix et Rhizoma and defined the development process of Glycyrrhizae Radix et Rhizoma processing. According to textual research from ancient times to today, there are many ways to process Glycyrrhizae Radix et Rhizoma. The processing methods without auxiliary materials include braising, frying, cooking, simmering and adding such auxiliary materials as wine, vinegar, salt, oil, ginger, honey, water and bile. There are 9 editions of the published Chinese Pharmacopoeia that document the processing of Glycyrrhizae Radix et Rhizoma, and 24 provinces and cities nationwide record the processing of Glycyrrhizae Radix et Rhizoma. At present, the 2015 edition of the Chinese Pharmacopoeia only records the processing technology of Glycyrrhizae Radix et Rhizoma honey, and the honey processing method is still widely usedtoday. Whether or not Zhigancao should be used uniformly for honey-processed Zhigancao today should be based on the processing methods of Chinese herbal medicine and its clinical use in previous ancient medical books. This paper provides a reference and historical basis for subsequent studies on other processing techniques of Glycyrrhizae Radix et Rhizoma, the rational selection of Glycyrrhizae Radix et Rhizoma varieties and the further development and utilization of corresponding medicinal materials.


Asunto(s)
Medicamentos Herbarios Chinos/análisis , Triterpenos , China , Extractos Vegetales , Rizoma/química
2.
Tob Induc Dis ; 222024.
Artículo en Inglés | MEDLINE | ID: mdl-38434517

RESUMEN

INTRODUCTION: Understanding the current burden of stomach cancer linked to smoking and the variations in trends across different locations, is crucial for developing effective prevention strategies. In this study, we present findings on the age-standardized death rate (ASDR) and age-standardized disability-adjusted life years (DALYs) rate attributed to smoking in 204 countries and territories spanning 21 regions from 1990 to 2019. METHODS: The data for this study were obtained from the Global Burden of Disease Study (GBD) 2019, which assessed 369 diseases and injuries, as well as 87 risk factors in 204 countries and 21 regions. To assess the trend in ASDR and age-standardized DALYs rate, the estimated annual percentage change (EAPC) was utilized. RESULTS: Between 1990 and 2019, smoking was found to be associated with a decrease in ASDR (EAPC = -2.20) and age-standardized DALYs (EAPC = -2.42) rates for gastric cancer. As the sociodemographic index (SDI) increased, the decline in rates also increased gradually. However, the decline was smallest in regions with low SDI (EAPCASDR = -1.34; EAPCage-standardized DALYs rate = -1.38). In 21 regions, both ASDR and DALYs rates experienced a decline. The smallest decline in ASDR was observed in Western Sub-Saharan Africa, with an EAPC of -0.80, while the smallest decline in DALYs rate was found in Oceania, with an EAPC of -0.81. Among the 204 countries analyzed, the Dominican Republic showed the highest increase in ASDR and age-standardized DALYs rate (EAPCASDR = 1.19; EAPCage-standardized DALYs rate = 1.21), followed by Afghanistan (EAPCASDR = 1.09; EAPCage-standardized DALYs rate = 1.09) and Sao Tome and Principe (EAPCASDR = 1.05; EAPCage-standardized DALYs rate = 1.03). In the year 2019, the highest ASDR and age-standardized DALYs rate was observed in East Asia, with the highest rates occurring in Mongolia. CONCLUSIONS: The burden of stomach cancer worldwide, adjusted for age, and related to smoking, has shown a decline from 1990 to 2019. However, regional disparities have been identified, with some areas experiencing an increase in this burden. These regions with a higher burden emphasize the necessity for the implementation of strong tobacco control measures.

3.
World J Gastrointest Oncol ; 16(5): 1995-2005, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38764807

RESUMEN

BACKGROUND: Limited knowledge exists regarding the casual associations linking blood metabolites and the risk of developing colorectal cancer. AIM: To investigate causal associations between blood metabolites and colon cancer. METHODS: The study utilized a two-sample Mendelian randomization (MR) analysis to investigate the causal impact of 486 blood metabolites on colorectal cancer. The primary method of analysis used was the inverse variance weighted model. To further validate the results several sensitivity analyses were performed, including Cochran's Q test, MR-Egger intercept test, and MR robust adjusted profile score. These additional analyses were conducted to ensure the reliability and robustness of the findings. RESULTS: After rigorous selection for genetic variation, 486 blood metabolites were included in the MR analysis. We found Mannose [odds ratio (OR) = 2.09 (1.10-3.97), P = 0.024], N-acetylglycine [OR = 3.14 (1.78-5.53), P = 7.54 × 10-8], X-11593-O-methylascorbate [OR = 1.68 (1.04-2.72), P = 0.034], 1-arachidonoylglycerophosphocholine [OR = 4.23 (2.51-7.12), P = 6.35 × 10-8] and 1-arachidonoylglycerophosphoethanolamine 4 [OR = 3.99 (1.17-13.54), P = 0.027] were positively causally associated with colorectal cancer, and we also found a negative causal relationship between Tyrosine [OR = 0.08 (0.01-0.63), P = 0.014], Urate [OR = 0.25 (0.10-0.62), P = 0.003], N-acetylglycine [0.73 (0.54-0.98), P = 0.033], X-12092 [OR = 0.89 (0.81-0.99), P = 0.028], Succinylcarnitine [OR = 0.48 (0.27-0.84), P = 0.09] with colorectal cancer. A series of sensitivity analyses were performed to confirm the rigidity of the results. CONCLUSION: This study showed a causal relationship between 10 blood metabolites and colorectal cancer, of which 5 blood metabolites were found to be causal for the development of colorectal cancer and were confirmed as risk factors. The other five blood metabolites are protective factors.

4.
Phytomedicine ; 123: 155154, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37976696

RESUMEN

OBJECTIVE: Alpinia oxyphylla fructus without impurities and shells is called "Yi-Zhi-Ren" (YZR) in Chinese, and traditionally used to alleviate enuresis. The aim of this study was to investigate the effects and underlying mechanisms of YZR in the treatment of overactive bladder (OAB) in spontaneously hypertensive rats (SHR), a vascular disorder-related OAB model. METHODS: A 3-week administration of YZR water extract (p.o.) was done, followed by urodynamics to measure bladder parameters. Changes in bladder structure were observed through H&E staining and Masson's staining. An integrated approach involving network pharmacology, transcriptomics and metabolomics was employed to elucidate the potential mechanisms of YZR, and the key proteins involved in the mechanisms were validated by Western blotting. Additionally, network pharmacology was used to predict the relationship between YZR's active components and validated proteins. RESULTS: YZR treatment significantly improved the bladder storage parameters, tightened the detrusor layer, reduced inflammatory infiltration, and decreased collagen proportion in the SHR bladder. These results indicated that YZR water extract can alleviate OAB symptoms and improve bladder structure. Integrated analysis suggested that YZR may affect extracellular matrix-receptor interaction and calcium signaling pathway. Western blotting results further confirmed that the reduction in key proteins, such as TGFß1, p-SMAD3, collagen III, Gq and PLCß1, involved in collagen synthesis and calcium signaling pathways after YZR treatment. Network pharmacology predicted that sitosterol, chrysin, and nootkatone were potential components responsible for YZR's therapeutic effect on OAB. CONCLUSION: YZR's mechanisms of action in treating OAB involved the TGFß1-SMAD3 signaling pathway-related collagen synthesis and Gq-PLCß1 calcium signaling pathway, which are associated with detrusor contraction frequency and strength, respectively.


Asunto(s)
Alpinia , Vejiga Urinaria Hiperactiva , Ratas , Animales , Vejiga Urinaria , Ratas Endogámicas SHR , Alpinia/química , Multiómica , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Colágeno
5.
J Mater Sci Mater Med ; 24(4): 1067-77, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23371765

RESUMEN

In this study, integrin expression, proliferation, and endothelial differentiation of adipose-derived stem cells (ADSCs) on pristine cobalt chrome (CoCr) surface, microstructured and nanostructured CoCr surfaces (obtained after treatment with piranha solution) were investigated. The results showed that proliferation of ADSCs on the substrates treated with piranha solution is not significantly different from that on the pristine substrates. However, quantitative real-time PCR analysis showed significantly enhanced up-regulation of CD31, vWF and eNOS from gene level by ADSCs on the nanostructured substrates but not on the microstructured substrates. The adsorption of vitronectin from the culture medium on the nanostructured substrates was higher than on the pristine and microstructured substrates. We speculate that this results in increased integrin αvß3 expression in the ADSCs, which may contribute partially to the enhanced endothelial differentiation of ADSCs on the nanostructured substrates. This study shows that ADSCs can be used to endothelialize stents in vitro and the endothelial differentiation of ADSC is enhanced on the nanostructured surfaces.


Asunto(s)
Tejido Adiposo/citología , Aleaciones de Cromo , Endotelio Vascular/citología , Nanoestructuras , Células Madre/citología , Adsorción , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Técnicas In Vitro , Microscopía Electrónica de Rastreo , Proteínas/química , Reacción en Cadena en Tiempo Real de la Polimerasa
6.
Biotechnol Bioeng ; 109(2): 336-45, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21956834

RESUMEN

Silicone has been utilized extensively for biomedical devices due to its excellent biocompatibility and biodurability properties. However, its surface is easily colonized by bacteria which will increase the probability of nosocomial infection. In the present work, a hydrophilic antimicrobial carboxymethyl chitosan (CMCS) layer has been grafted on medical grade silicone surface pre-treated with polydopamine (PDA). The increase in hydrophilicity was confirmed from contact angle measurement. Bacterial adhesion tests showed that the PDA-CMCS coating reduced the adhesion of Escherichia coli and Proteus mirabilis by ≥ 90%. The anti-adhesion property was preserved even after the aging of the functionalized surfaces for 21 days in phosphate-buffered saline (PBS), and also after autoclaving at 121°C for 20 min. Both E. coli and P. mirabilis readily form biofilms on the pristine surface under static and flow conditions but with the PDA-CMCS layer, biofilm formation is inhibited. The flow experiments indicated that it is more difficult to inhibit biofilm formation by the highly motile P. mirabilis as compared to E. coli. No significant cytotoxicity of the modified substrates was observed with 3T3 fibroblasts.


Asunto(s)
Antiinfecciosos/química , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Escherichia coli/fisiología , Proteus mirabilis/fisiología , Siliconas/química , Células 3T3 , Análisis de Varianza , Animales , Antiinfecciosos/farmacología , Quitosano/química , Quitosano/farmacología , Escherichia coli/efectos de los fármacos , Indoles/química , Indoles/farmacología , Ratones , Polímeros/química , Polímeros/farmacología , Proteus mirabilis/efectos de los fármacos , Propiedades de Superficie
7.
Front Oncol ; 12: 979809, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36203427

RESUMEN

Objective: Trends in the incidence, disability-adjusted life-years (DALYs), and mortality rate of cervical cancer remain unknown. Methods: The average annual percent changes (AAPCs) and relative risks (RR) in the incidence, DALYs, and mortality rate were determined using a joinpoint regression analysis; the net age, period, and cohort effects on above rates were evaluated. Results: A significant increase in age-standardized incidence (AAPC, 0.9%; 95CI: 0.8, 1.1) but significant decreases in age-standardized DALYs (AAPC, -0.4%; 95%CI: -0.60, -0.20) and the mortality rate (AAPC, -0.4%; 95CI: -0.6, -0.3) were observed. As for age-specific rates, the incidence was higher in younger age groups, and the DALYs and mortality rate were lower in older age groups. The effects of age included a slight but significant increase in the RR with advancing age from 35 to 94 years; the period effect included a significant increase in the incidence over the 2005-2019 periods; and the cohort effect included a substantial increase in the incidence from earlier to later birth cohorts. Conclusions: The incidence of cervical cancer increased from 1990 to 2019, particularly in younger age groups, and the DALYs and mortality rate decreased in the older age groups. Furthermore, the incidence increased with age, period, and cohort.

8.
J Mater Sci Mater Med ; 22(10): 2283-92, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21786132

RESUMEN

Poly(methyl methacrylate)-based bone cements are functionalized with mesoporous silica nanoparticles (MSN) to enable a highly efficient and sustained release of antibiotics to reduce the risk of post-operative joint infection. To overcome the limited drug release of 5% for only 1 day with the current commercial-grade bone cements, a 8 wt% MSN-formulated bone cement is able to increase the drug release efficiency by 14-fold and sustain the release for up to 80 days. The loaded MSN is suggested to build up an effective network of rod-shaped silica particles with uniformly arranged nanoporous channels, which is responsible for the effective drug diffusion and extend time-release to the external surfaces. MSN has no detrimental effect on the critical weight-bearing bending modulus and compression strength of bone cement. In vitro assay test results show a much sustained antibacterial effect and low cytotoxicity of MSN demonstrating the potential applicability of MSN-formulated bone cement.


Asunto(s)
Antibacterianos/química , Cementos para Huesos/química , Gentamicinas/química , Nanopartículas/química , Polimetil Metacrilato/química , Dióxido de Silicio/química , Células 3T3 , Animales , Antibacterianos/administración & dosificación , Materiales Biocompatibles , Fibroblastos/efectos de los fármacos , Ratones , Microscopía Electrónica de Rastreo , Factores de Tiempo
9.
Biotechnol Bioeng ; 104(1): 30-9, 2009 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-19408318

RESUMEN

Essential oils are known to possess antimicrobial and antioxidant activity while chitosan is a biocompatible polymer with antibacterial activity against a broad spectrum of bacteria. In this work, nanoparticles with both antioxidant and antibacterial properties were prepared by grafting eugenol and carvacrol (two components of essential oils) on chitosan nanoparticles. Aldehyde groups were first introduced in eugenol and carvacrol, and the grafting of these oils to chitosan nanoparticles was carried out via the Schiff base reaction. The surface concentration of the grafted essential oil components was determined by X-ray photoelectron spectroscopy (XPS). The antioxidant activities of the carvacrol-grafted chitosan nanoparticles (CHCA NPs) and the eugenol-grafted chitosan nanoparticles (CHEU NPs) were assayed with diphenylpicrylhydrazyl (DPPH). Antibacterial assays were carried out with a representative gram-negative bacterium, Escherichia coli (E. coli) and a gram-positive bacterium, Staphylococcus aureus (S. aureus). The grafted eugenol and carvacrol conferred antioxidant activity to the chitosan nanoparticles, and the essential oil component-grafted chitosan nanoparticles achieved an antibacterial activity equivalent to or better than that of the unmodified chitosan nanoparticles. Cytotoxicity assays using 3T3 mouse fibroblast showed that the cytotoxicity of CHEU NPs and CHCA NPs were significant lower than those of the pure essential oils.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Quitosano/farmacología , Eugenol/farmacología , Monoterpenos/farmacología , Nanopartículas/química , Animales , Antibacterianos/metabolismo , Antibacterianos/toxicidad , Antioxidantes/metabolismo , Antioxidantes/toxicidad , Compuestos de Bifenilo/metabolismo , Células Cultivadas , Quitosano/metabolismo , Quitosano/toxicidad , Cimenos , Escherichia coli/efectos de los fármacos , Eugenol/metabolismo , Eugenol/toxicidad , Fibroblastos/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Monoterpenos/metabolismo , Monoterpenos/toxicidad , Oxidación-Reducción , Picratos/metabolismo , Staphylococcus aureus/efectos de los fármacos
10.
Biomacromolecules ; 10(6): 1603-11, 2009 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-19391583

RESUMEN

Orthopedic implant failure has been attributed mainly to loosening of the implant from host bone, which may be due to poor bonding of the implant material to bone tissue, as well as to bacterial infection. One promising strategy to enhance tissue integration is to develop a selective biointeractive surface that simultaneously enhances bone cell function while decreasing bacterial adhesion. In this in vitro study, the surfaces of titanium alloy substrates were functionalized by first covalently grafting carboxymethyl chitosan (CMCS), followed by the conjugation of bone morphogenetic protein-2 (BMP-2) to the CMCS-grafted surface. Bacterial adhesion on the substrates was assayed with Staphylococcus aureus and Staphylococcus epidermidis . Cell functions were investigated using osteoblasts and human bone marrow-derived mesenchymal stem cells. The results showed that bacterial adhesion on both the CMCS and CMCS-BMP-2 functionalized surfaces was significantly reduced compared to that on the pristine substrates. In addition, the CMCS-BMP-2 modified substrates significantly promoted attachment, alkaline phosphatase activity, and calcium mineral deposition of both osteoblast and human bone marrow-derived mesenchymal stem cells. The achievement of the dual functions of bacterial adhesion reduction and cell function promotion by the CMCS-BMP-2 modified titanium substrates illustrates the good potential of such surfaces for enhancement of tissue integration and implant longevity.


Asunto(s)
Proteína Morfogenética Ósea 2/química , Quitosano/química , Oseointegración , Titanio/química , Fosfatasa Alcalina/metabolismo , Adhesión Bacteriana , Calcio/metabolismo , Proliferación Celular , Humanos , Osteoblastos/citología , Osteoblastos/enzimología , Osteoblastos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/citología , Staphylococcus epidermidis/citología , Propiedades de Superficie
12.
J R Soc Interface ; 16(152): 20180799, 2019 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-30836894

RESUMEN

Osseointegration of metallic implants in porous osteoporotic bone remains a challenge. Surface modification of implants to reduce peri-implant osteoclastic bone resorption was explored in the study. Bioinspired polydopamine (pDOP) and polyphenol tannic acid (pTAN) are nature-derived universal coating systems that have emerged either as a sole coating or ad-layer for biomolecular conjugation on different biomaterials. The effects pDOP and pTAN on osteoclast development have not been reported before. In this study, osteoclast development was investigated on titanium (Ti) substrates coated with pDOP (Ti-pDOP) and pTAN (Ti-pTAN). The results showed that Ti-pDOP and Ti-pTAN coating reduced tartrate-resistant acid phosphatase activity and osteoclast cell number as compared with pristine Ti. Intriguingly, the reduction was higher on Ti-pTAN than on Ti-pDOP. Economical and biocompatible tannic acid serves as a superior coating in decreasing osteoclast activity when compared with that of pDOP coating and could be used to modulate osteoclast activity at bone-implant interfaces.


Asunto(s)
Interfase Hueso-Implante , Diferenciación Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos , Indoles , Osteoclastos/metabolismo , Polímeros , Taninos , Titanio , Animales , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Indoles/química , Indoles/farmacología , Ratones , Polímeros/química , Polímeros/farmacología , Porosidad , Células RAW 264.7 , Taninos/química , Taninos/farmacología , Titanio/química , Titanio/farmacología
13.
Polymers (Basel) ; 11(8)2019 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-31362449

RESUMEN

Implant anchorage remains a challenge, especially in porous osteoporotic bone with high osteoclast activity. The implant surface is modified with osteogenic molecules to stimulate osseointegration. Strontium (Sr) is known for its osteogenic and anti-osteoclastogenic effects. In this study, Sr was immobilized on a titanium (Ti) surface using bioinspired polyphenol tannic acid (pTAN) coating as an ad-layer (Ti-pTAN). Two separate coating techniques were employed for comparative analysis. In the first technique, Ti was coated with a tannic acid solution containing Sr (Ti-pTAN-1Stp). In the second method, Ti was first coated with pTAN, before being immersed in a SrCl2 solution to immobilize Sr on Ti-pTAN (Ti-pTAN-2Stp). Ti-pTAN-1Stp and Ti-pTAN-2Stp augmented the alkaline phosphatase activity, collagen secretion, osteocalcin production and calcium deposition of MC3T3-E1 cells as compared to those of Ti and Ti-pTAN. However, osteoclast differentiation of RAW 264.7, as studied by TRAP activity, total DNA, and multinucleated cell formation, were decreased on Ti-pTAN, Ti-pTAN-1Stp and Ti-pTAN-2Stp as compared to Ti. Of all the substrates, osteoclast activity on Ti-pTAN-2Stp was the lowest. Hence, an economical and simple coating technique using pTAN as an adlayer preserved the dual biological effects of Sr. These results indicate a promising new approach to tailoring the cellular responses of implant surfaces.

14.
J Funct Biomater ; 9(1)2018 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-29495358

RESUMEN

Biomaterial integration in bone depends on bone remodelling at the bone-implant interface. Optimal balance of bone resorption by osteoclasts and bone deposition by osteoblasts is crucial for successful implantation, especially in orthopaedic surgery. Most studies examined osteoblast differentiation on biomaterials, yet few research has been conducted to explore the effect of different orthopaedic implants on osteoclast development. This review covers, in detail, the biology of osteoclasts, in vitro models of osteoclasts, and modulation of osteoclast activity by different implant surfaces, bio-ceramics, and polymers. Studies show that surface topography influence osteoclastogenesis. For instance, metal implants with rough surfaces enhanced osteoclast activity, while smooth surfaces resulted in poor osteoclast differentiation. In addition, surface modification of implants with anti-osteoporotic drug further decreased osteoclast activity. In bioceramics, osteoclast development depended on different chemical compositions. Strontium-incorporated bioceramics decreased osteoclast development, whereas higher concentrations of silica enhanced osteoclast activity. Differences between natural and synthetic polymers also modulated osteoclastogenesis. Physiochemical properties of implants affect osteoclast activity. Hence, understanding osteoclast biology and its response to the natural microarchitecture of bone are indispensable to design suitable implant interfaces and scaffolds, which will stimulate osteoclasts in ways similar to that of native bone.

15.
J Biomed Mater Res B Appl Biomater ; 106(8): 2878-2887, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29722119

RESUMEN

The incidence of bone disorders, from trauma, tissue degeneration due to ageing, pathological conditions to cancer, has been increasing. The pursuit for bone graft substitutes to assist in regenerating large bone defects is ever growing as a result of the shortage in conventional autografts and allografts, in addition to the associated risks of disease transmission. However, the use of alloplastic biomaterials is limited in clinical settings, as further investigations are required to address the properties of synthetic grafts to mimic the native bone tissue and deliver desirable biomolecules to facilitate bone regeneration. This review discusses the fundamental structure and properties of bone with the emphasis on organic and inorganic components that are important for the biomaterial design. The main focus will be on the advancement and usage of bioactive glass (BG) for bone tissue engineering due to its similarity to the natural inorganic constituent of bone. The various BG synthetic processes, modifications of composition, as well as the biomolecule delivery will be discussed in great detail. As the properties of BG are tuneable according to clinical needs, it creates a new paradigm in addition to displaying its superior potential for bone tissue engineering and translational medicine in the field of orthopedic surgery. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2878-2887, 2018.


Asunto(s)
Huesos/metabolismo , Vidrio/química , Nanopartículas/química , Ingeniería de Tejidos/métodos , Animales , Humanos , Porosidad
16.
ACS Appl Mater Interfaces ; 10(12): 9988-9998, 2018 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-29513524

RESUMEN

Estrogen, a steroid hormone, plays an important role in modulating osteoclast proliferation and development. Estrogen deficiency boosts osteoclast activity, leading to osteoporosis in elderly women. In this study, 17-ß estradiol (E2)-loaded poly(ε-caprolactone) (PCL)/silk fibroin (SF) electrospun microfibers were developed as a proposed localized E2 delivery system to treat osteoporotic fractures. PCL is a synthetic polymer known for its biocompatibility and excellent mechanical properties. The bioactivity of PCL was enhanced by mixing it with a natural SF polymer that has low immunogenicity and inherent bioactivity. Different ratios of PCL/SF blends were electrospun and characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle measurement. PCL and SF at a ratio of 50:50 (PCL50/SF50) augmented cell proliferation of murine preosteoblast MC3T3-E1 cells and murine preosteoclast RAW 264.7 cells. Hence, PCL50/SF50 was selected and mixed with three concentrations of E2 to produce electrospun fiber mesh (0.1% E2@PCL/SF, 1% E2@PCL/SF, and 5% E2@PCL/SF). Sustained release of E2 was obtained for about 3 weeks at higher E2 concentration 5% E2@PCL/SF. An E2-loaded PCL50/SF50 elecrospun microfiber (1% E2@PCL/SF and 5% E2@PCL/SF) reduced tartrate-resistant acid phosphate activity, total DNA, and multinucleated cell formation of osteoclasts. On the other hand, the alkaline phosphatase activity and collagen I expression of osteoblasts were retained on all E2-loaded electrospun microfibers. The E2@PCL/SF system shows potential to be used for localized E2 delivery for the treatment of osteoporotic fractures.


Asunto(s)
Osteoblastos , Osteoclastos , Animales , Estradiol , Fibroínas , Ratones , Nanofibras , Poliésteres , Ingeniería de Tejidos , Andamios del Tejido
17.
Nanoscale ; 10(38): 18341-18353, 2018 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-30255905

RESUMEN

Osteoporosis, a systemic skeletal disease prevalent in elderly women, is associated with post-menopausal estrogen deficiency. Although systemic administration of exogenous estradiol (E2) reduced fragility fractures, the treatment has adverse effects. Localized delivery technologies of E2 could be utilized to circumvent the systemic adverse effects of systemic administration. In this study, a localized E2 delivery system is developed. Mesoporous bioactive glass nanoparticles (MBGNPs) with inherent osteogenic properties are modified with ß-cyclodextrin (CD-MBGNPs) to enhance their affinity for E2. To ensure mechanical stability and integrity, E2 loaded CD-MBGNPs are further electrospun with silk fibroin (SF) to produce a nanofibrous mesh (E2@CD-MBGNPs/SF). The incorporation of MBGNPs in SF enhances in vitro apatite formation and sustains the constant release of E2. Moreover, osteoblast proliferation and differentiation markers such as alkaline phosphatase activity, collagen 1 and osteocalcin expression of MC3T3-E1 are augmented in CD-MBGNPs/SF and E2@CD-MBGNPs/SF as compared to SF nanofibers. On the other hand, osteoclast DNA, tartrate resistant acid phosphatase activity and multinucleated cell formation are reduced in E2@CD-MBGNPs/SF as compared to CD-MBGNPs/SF and SF. Hence the presence of CD-MBGNPs in SF stimulates osteoblast function whereas E2 incorporation in CD-MBGNPs/SF reduces osteoclast activity. This is the first report to develop CD-MBGNPs/SF as a localized delivery system for hydrophobic molecules such as estradiol to treat osteoporosis.


Asunto(s)
Sistemas de Liberación de Medicamentos , Estradiol/administración & dosificación , Fibroínas/química , Osteoporosis/tratamiento farmacológico , beta-Ciclodextrinas/química , Animales , Apatitas/análisis , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Liberación de Fármacos , Estradiol/química , Estradiol/farmacología , Ratones , Nanofibras/administración & dosificación , Nanofibras/química , Nanofibras/ultraestructura , Nanopartículas/química , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ratas
18.
J Funct Biomater ; 8(4)2017 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-28956821

RESUMEN

To improve orthopedic implant fixation and reduce post-operative complications, osteogenic molecules are delivered locally by immobilizing them on the surface of implants, which will modulate the biology of cell attachment and differentiation on the implant surface. Estradiol, a natural steroid hormone, maintains bone metabolism by decreasing bone resorption. It either directly or indirectly affects osteoclasts. In this work, estradiol was immobilized on a titanium surface by polydopamine adlayer. Immobilization of estradiol was confirmed by X-ray electron spectroscopy (XPS), immunofluorescence staining and enzyme-linked immunosorbent assay (ELISA). Estradiol-modified substrates enhanced alkaline phosphatases activity (ALP) and calcium deposition of osteoblasts. However, these substrates did not decrease tartrate-resistant acid phosphatase (TRAP) activity and actin ring formation of the osteoclast. The scanning electron microscopic (SEM) images of estradiol-modified substrates showed the formation of estradiol crystals, which decreased the potency of immobilized estradiol. Despite having a successful immobilization of estradiol via the polydopamine technique, the bioavailability and potency of coated estradiol is reduced due to crystallization, suggesting that this is not a suitable system for localized estradiol delivery as tested in vitro here. Consequently, other suitable platforms have to be explored for immobilizing estradiol that will prevent crystal formation while preserving the biological activity.

19.
J Mech Behav Biomed Mater ; 72: 163-170, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28499164

RESUMEN

The influence of mesoporous silica nanoparticles (MSNs) loaded with antibiotics on the mechanical properties of functional poly(methyl methacrylate)-(PMMA) based bone cements is investigated. The incorporation of MSNs to the bone cements (8.15wt%) shows no detrimental effects on the biomechanical properties of the freshly solidified bone cements. Importantly, there are no significant changes in the compression strength and bending modulus up to 6 months of aging in PBS buffer solution. The preserved mechanical properties of MSN-functionalized bone cements is attributed to the unchanged microstructures of the cements, as more than 96% of MSNs remains in the bone cement matrix to support the cement structures after 6 months of aging. In addition, the MSN-functionalized bone cements are able to increase the drug release of gentamicin (GTMC) significantly as compared with commercially available antibiotic-loaded bone cements. It can be attributed to the loaded nano-sized MSNs with uniform pore channels which build up an effective nano-network path enable the diffusion and extended release of GTMC. The combination of excellent mechanical properties and sustainable drug delivery efficiency demonstrates the potential applicability of MSN-functionalized PMMA bone cements for orthopedic surgery to prevent post-surgery infection.


Asunto(s)
Antibacterianos/química , Cementos para Huesos/química , Polimetil Metacrilato/química , Dióxido de Silicio/química , Liberación de Fármacos , Ensayo de Materiales , Nanopartículas/química
20.
Sci Rep ; 7(1): 15549, 2017 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-29138445

RESUMEN

Huang-Lian-Jie-Du-Tang (HLJDT), a traditional formula with four TCM herbs, has been used for hundred years for different diseases. The current study aimed to assess the inhibitory activity of HLJDT against H1N1 neuraminidase (NA-1), and identify potent NA-1 inhibitors from its plasma profile. The in vitro NA-1 study has shown that the water extract of HLJDT potently inhibited NA-1 (IC50 = 112.6 µg/ml; Ki = 55.6 µg/ml) in a competitive mode. The IC50 values of the water extracts of its four herbs were as follows: Coptidis Rhizoma, 96.1 µg/ml; Phellodendri Chinensis Cortex, 108.6 µg/ml; Scutellariae Radix, 303.5 µg/ml; Gardeniae Fructus, 285.0 µg/ml. Thirteen compounds found in the plasma profile of HLJDT were also identified as potent NA-1 inhibitors, which included jatrorrhizine, palmatine, epiberberine, geniposide, oroxylin A, berberine, coptisine, baicalein, wogonoside, phellodendrine, wogonin, oroxylin A-7-O-glucuronide and baicalin (sorted in ascending order by their IC50 values). Their inhibitory activities were consistent with molecular docking analysis when considering crystallographic water molecules in the ligand-binding pocket of NA-1. Our current findings suggested that HLJDT can be used as a complementary medicine for H1N1 infection and its potent active compounds can be developed as NA-1 inhibitors.


Asunto(s)
Medicamentos Herbarios Chinos/química , Inhibidores Enzimáticos/química , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Gripe Humana/tratamiento farmacológico , Neuraminidasa/química , Animales , Berberina/análogos & derivados , Berberina/química , Alcaloides de Berberina/química , Coptis chinensis , Cristalografía , Medicamentos Herbarios Chinos/administración & dosificación , Inhibidores Enzimáticos/administración & dosificación , Flavanonas/química , Gardenia/química , Humanos , Subtipo H1N1 del Virus de la Influenza A/patogenicidad , Gripe Humana/virología , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Neuraminidasa/antagonistas & inhibidores , Ratas , Scutellaria baicalensis/química
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