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1.
J Nanobiotechnology ; 19(1): 201, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229725

RESUMO

BACKGROUND: The design of stable and biocompatible black phosphorus-based theranostic agents with high photothermal conversion efficiency and clear mechanism to realize MRI-guided precision photothermal therapy (PTT) is imminent. RESULTS: Herein, black phosphorus nanosheets (BPs) covalently with mono-dispersed and superparamagnetic ferrous selenide (FeSe2) to construct heteronanostructure nanoparticles modified with methoxy poly (Ethylene Glycol) (mPEG-NH2) to obtain good water solubility for MRI-guided photothermal tumor therapy is successfully designed. The mechanism reveals that the enhanced photothermal conversion achieved by BPs-FeSe2-PEG heteronanostructure is attributed to the effective separation of photoinduced carriers. Besides, through the formation of the P-Se bond, the oxidation degree of FeSe2 is weakened. The lone pair electrons on the surface of BPs are occupied, which reduces the exposure of lone pair electrons in air, leading to excellent stability of BPs-FeSe2-PEG. Furthermore, the BPs-FeSe2-PEG heteronanostructure could realize enhanced T2-weighted imaging due to the aggregation of FeSe2 on BPs and the formation of hydrogen bonds, thus providing accurate PTT guidance and generating hyperthermia to inhabit tumor growth under NIR laser with negligible toxicity in vivo. CONCLUSIONS: Collectively, this work offers an opportunity for fabricating BPs-based heteronanostructure nanomaterials that could simultaneously enhance photothermal conversion efficiency and photostability to realize MRI-guided cancer therapy.


Assuntos
Compostos Ferrosos/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas/química , Fósforo/química , Fósforo/farmacologia , Terapia Fototérmica/métodos , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Hipertermia Induzida , Camundongos , Nanoestruturas , Fototerapia/métodos , Polietilenoglicóis/química , Medicina de Precisão
2.
Am J Orthod Dentofacial Orthop ; 155(5): 670-680, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31053283

RESUMO

INTRODUCTION: This study investigated the effects of different doses of parathyroid hormone (PTH) on orthodontic tooth movement after mandibular ramus osteotomy and the associated dose-response relationship. METHODS: One-hundred twenty rabbits were divided into 2 experimental groups (A and B) and 2 control groups (control group and negative control group). An experimental model of mandibular ramus osteotomy with installation of an orthodontic tooth movement device was established in groups A and B and the control group. After surgery, groups A and B received intermittent subcutaneous injections of PTH, 20 and 40 µg/kg, respectively, and the control group received injections of normal saline solution. The negative control group underwent installation of the orthodontic tooth movement device without mandibular ramus osteotomy and received normal saline solution after surgery. Changes in expression of RANKL and RUNX2 in the periodontal tissues of the first molars were evaluated by means of immunohistochemical analysis and quantitative fluorescence polymerase chain reaction. RESULTS: Movement of the first molars was more rapid in group B than in group A in the 21 days after surgery. Significantly higher RANKL mRNA levels and lower RUNX2 mRNA levels were detected on the compression side of the periodontal tissues in groups A and B than in the control groups. There was a significant difference in RANKL and RUNX2 expression levels between group B and the control groups at all time points. CONCLUSIONS: Mandibular ramus osteotomy combined with high-dose PTH can increase catabolism on the compressed periodontal tissues, thereby accelerating remodeling of periodontal bone and promoting orthodontic tooth movement after surgery.


Assuntos
Osteotomia Mandibular , Hormônio Paratireóideo/farmacologia , Técnicas de Movimentação Dentária , Animais , Remodelação Óssea/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imuno-Histoquímica , Hormônio Paratireóideo/administração & dosagem , Reação em Cadeia da Polimerase , Ligante RANK/metabolismo , Coelhos
3.
Mol Pharm ; 13(4): 1298-307, 2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-26894988

RESUMO

Combination therapy has been developed as a promising therapeutic approach for hepatocellular carcinoma therapy. Here we report a low toxicity and high performance nanoparticle system that was self-assembled from a poly(ethylenimine)-glycyrrhetinic acid (PEI-GA) amphiphilic copolymer as a versatile gene/drug dual delivery nanoplatform. PEI-GA was synthesized by chemical conjugation of hydrophobic GA moieties to the hydrophilic PEI backbone via an acylation reaction. The PEI-GA nanocarrier could encapsulate doxorubicin (DOX) efficiently with loading level about 12% and further condense DNA to form PEI-GA/DOX/DNA complexes to codeliver drug and gene. The diameter of the complexes is 102 ± 19 nm with zeta potential of 19.6 ± 0.2 mV. Furthermore, the complexes possess liver cancer targeting ability and could promote liver cancer HepG2 cell internalization. Apoptosis of cells could be induced by chemotherapy of DOX, and PI3K/Akt/mTOR signaling pathway acts a beneficial effect on the modulation of autophagy. Here, it is revealed that utilizing PEI-GA/DOX/shAkt1 complexes results in effective autophagy and apoptosis, which are useful to cause cell death. The induction of superfluous autophagy is reported to induce type-II cell death and also could increase the sensity of chemotherapy to tumor cells. In this case, combining autophagy and apoptosis is meaningful for oncotherapy. In this study, PEI-GA/DOX/shAkt1 has demonstrated favorable tumor target ability, little side effects, and ideal antitumor efficacy.


Assuntos
Autofagia/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Ácido Glicirretínico/química , Nanopartículas/química , Polietilenoimina/química , Polímeros/farmacologia , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , Animais , Doxorrubicina/uso terapêutico , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Nanopartículas/uso terapêutico , Polímeros/química , Polímeros/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/genética
4.
Int J Legal Med ; 129(1): 179-86, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25030187

RESUMO

The aim of this study was to assess the accuracy of Cameriere's methods on dental age estimation in the northern Chinese population. A sample of orthopantomographs of 785 healthy children (397 girls and 388 boys) aged between 5 and 15 years was collected. The seven left permanent mandibular teeth were evaluated with Cameriere's method. The sample was split into a training set to develop a Chinese-specific prediction formula and a test set to validate this novel developed formula. Following the training dataset study, the variables gender (g), x 3 (canine teeth), x 4 (first premolar), x 7 (second molar), N 0, and the first-order interaction between s and N 0 contributed significantly to the fit, yielding the following linear regression formula: Age = 10.202 + 0.826 g - 4.068x 3 - 1.536x 4 - 1.959x 7 + 0.536 N 0 - 0.219 s [Symbol: see text] N 0, where g is a variable, 1 for boys and 0 for girls. The equation explained 91.2 % (R (2) = 0.912) of the total deviance. By analyzing the test dataset, the accuracy of the European formula and Chinese formula was determined by the difference between the estimated dental age (DA) and chronological age (CA). The European formula verified on the collected Chinese children underestimated chronological age with a mean difference of around -0.23 year, while the Chinese formula underestimated the chronological age with a mean difference of -0.04 year. Significant differences in mean differences in years (DA - CA) and absolute difference (AD) between the Chinese-specific prediction formula and Cameriere's European formula were observed. In conclusion, a Chinese-specific prediction formula based on a large Chinese reference sample could ameliorate the age prediction accuracy in the age group of children.


Assuntos
Determinação da Idade pelos Dentes/métodos , Povo Asiático , Ápice Dentário/crescimento & desenvolvimento , Adolescente , Criança , Pré-Escolar , China , Feminino , Humanos , Modelos Lineares , Masculino , Radiografia Panorâmica , Ápice Dentário/diagnóstico por imagem
5.
Int J Legal Med ; 128(4): 659-65, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24532176

RESUMO

Age estimation by third molar mineralization has been developed for a period of time. Recent studies showed that impaction status has an influence on the rate of the third molar mineralization in Europids and male Black African populations. In this regard, the present study was conducted to determine whether the impaction status could delay the chronological process of third molar mineralization in northwestern Chinese population too. A total of 3,512 digital orthopantomograms of 1,255 male and 2,257 female northwestern Chinese subjects aged from 11 to 26 years were assessed based on the formation stages described by Demirjian et al. with two modifications. Mineralization stage and impaction status were determined for all third molars. Statistical measures were calculated at stages C-H in the male and female gender for both impacted and non-impacted third molars. It was ascertained that the mean ages with impacted third molars at stages C-H were 0.02-1.42 years higher in males and 0.04-1.52 years higher in females than those with non-impacted third molars, but statistical differences were only found at stages C, D, and E in males and stages D and E in females. The probabilities of being under 14, 16, or 18 years of age with non-impacted third molars were all higher than those with impacted third molars. The results prove that impacted third molars show significant slower mineralization than non-impacted ones at stages D and E in both males and females of northwestern Chinese population. It is recommended to consider the influence of impaction on the rate of third molar mineralization for dental age estimation.


Assuntos
Determinação da Idade pelos Dentes/métodos , Dente Serotino/crescimento & desenvolvimento , Calcificação de Dente , Dente Impactado/diagnóstico por imagem , Adolescente , Adulto , Povo Asiático , Criança , China , Feminino , Humanos , Masculino , Dente Serotino/diagnóstico por imagem , Radiografia Panorâmica , Adulto Jovem
6.
J Oral Maxillofac Surg ; 72(2): 419-30, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24071373

RESUMO

PURPOSE: Parathyroid hormone (PTH) is a major regulator of bone metabolism. Various animal studies and clinical trials have addressed the treatment of osteoporosis and fracture healing with the intermittent administration of PTH, whereas few studies have investigated the effects of PTH on mandibular defect repair. This study sought to examine the feasibility of using recombinant human PTH (rhPTH) to promote the repair of mandibular defects and to provide a preliminary investigation of the underlying mechanisms of this phenomenon. MATERIALS AND METHODS: A mandibular defect model was established using Japanese white rabbits. The experimental animals were randomly divided into a control group that received postoperative subcutaneous injections of normal saline on alternate days and an experimental group that received postoperative subcutaneous injections of rhPTH 25 µg on alternate days. The experimental animals were sacrificed at 1, 2, 3, and 4 weeks after the operation to perform x-ray imaging and bone histomorphometric examinations of the defect areas. Changes in serum levels of bone-specific alkaline phosphatase (bALP) and osteoprotegerin (OPG) over time were examined. RESULTS: Compared with the control group, the experimental group exhibited newly generated bone matrix in the mandibular defect area at earlier stages. In the experimental group, the bone trabeculae were arranged in an orderly manner, and uniform calcification was observed. Marked hyperplasia of osteoblasts was observed in the new bone tissue of the experimental group, but significantly less hyperplasia of osteoblasts was observed in the control group. In the 2 groups, the average serum bALP and OPG levels increased after the operation and then gradually decreased. In the experimental group, levels of bALP and OPG at 1 week and 2 weeks after the operation were significantly different from preoperative levels. In the control group, the OPG level at 2 weeks after the operation was significantly different from the preoperative OPG level. A comparison of serum bALP and OPG levels at each examined time point showed no significant difference between the 2 groups. CONCLUSION: The intermittent subcutaneous injection of rhPTH 25 µg/day promotes the healing of mandibular defects in rabbits. The application of rhPTH may facilitate mandible regeneration by increasing quantities of osteoblasts, accelerating bone turnover metabolism, and upregulating OPG levels.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Regeneração Óssea/efeitos dos fármacos , Doenças Mandibulares/tratamento farmacológico , Hormônio Paratireóideo/uso terapêutico , Fosfatase Alcalina/metabolismo , Animais , Injeções Subcutâneas , Mandíbula/patologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoprotegerina/metabolismo , Hormônio Paratireóideo/administração & dosagem , Hormônio Paratireóideo/farmacologia , Coelhos , Distribuição Aleatória , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico
7.
Bioresour Technol ; 381: 129106, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127172

RESUMO

The potential of green solvents, specifically deep eutectic solvents (DESs), has piqued the interest of researchers in the field of lignocellulose pretreatment. To enhance the enzymatic digestion efficiency of waste rice hull (RCH), an effective pretreatment approach was developed using the DES [AA][CATB], which was made with acetic acid (AA) and cetyltrimethylammonium bromide (CTAB). The results showed that [AA][CATB] improved enzymatic saccharification by 3.7 times compared to raw RCH and efficiently eliminated lignin and removed xylan. The improvement in enzymatic hydrolysis efficiency was then interpreted by a series of characterizations that showed a great morphological changed RCH with an obvious accessibility increase and a lignin surface area and hydrophobicity reduction. This work demonstrates that functional, and easily recoverable DESs have potential for improving the efficiency of lignocellulose pretreatment in biorefineries, providing a promising approach for developing green solvents and achieving more sustainable and efficient biorefinery processes.


Assuntos
Lignina , Oryza , Solventes Eutéticos Profundos , Tensoativos , Hidrólise , Solventes , Biomassa , Ácido Acético
8.
J Hazard Mater ; 417: 126130, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-34229397

RESUMO

Novel composite foam (CMCTS-PUF-s) was prepared by immobilizing carboxymethyl chitosan (CMCTS) on polyurethane foam (PUF) in which amino groups in CMCTS reacted with isocyanate groups in polyurethane prepolymer. The adsorption capacity of the optimal composite foam (CMCTS-PUF-5) reached to 118.2 mg/g with 5% CMCTS loading. The removal rate to methylene blue (MB) was up to 97.1%, which was obviously higher than 18.9% of PUF. After recycling for five times, the removal rate still reached 83.2%, which strongly proved the excellent reusability of immobilizing CMCTS modified PUF. The characterization results of FTIR and TG showed that CMCTS was well loaded on PUF by covalent bond. The Young's modulus and tensile strength of CMCTS-PUF-5 were increased by 252% and 97% compared with that of PUF. MIP characterization result showed the porosity of CMCTS-PUF-5 was 73.99% and the pore sizes were mainly distributed between 50 and 150 µm, which provide sufficient diffusion channels and active sites for MB dyes. The adsorption kinetics and isotherm proved pseudo-second-order kinetic model and Langmuir isotherm model could well describe the adsorption process of CMCTS-PUF-5. Therefore, CMCTS-PUF-s presents excellent recoverability, high stability and attractive adsorption efficiency, shows the potential application in future treatment of dye wastewater.


Assuntos
Quitosana , Poluentes Químicos da Água , Adsorção , Cinética , Azul de Metileno , Poliuretanos
9.
Exp Biol Med (Maywood) ; 246(15): 1727-1739, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33926259

RESUMO

Bone mass loss (osteoporosis) seen in postmenopausal women is an adverse factor for implant denture. Using an ovariectomized rat model, we studied the mechanism of estrogen-deficiency-caused bone loss and the therapeutic effect of Zoledronic acid. We observed that ovariectomized-caused resorption of bone tissue in the mandible was evident at four weeks and had not fully recovered by 12 weeks post-ovariectomized compared with the sham-operated controls. Further evaluation with a TUNEL assay showed ovariectomized enhanced apoptosis of osteoblasts but inhibited apoptosis of osteoclasts in the mandible. Zoledronic acid given subcutaneously as a single low dose was shown to counteract both of these ovariectomized effects. Immunohistochemical staining showed that ovariectomized induced the protein levels of RANKL and the 65-kD subunit of the NF-κB complex mainly in osteoclasts, as confirmed by staining for TRAP, a marker for osteoclasts, whereas zoledronic acid inhibited these inductions. Western blotting showed that the levels of RANKL, p65, as well as the phosphorylated form of p65, and IκB-α were all higher in the ovariectomized group than in the sham and ovariectomized + zoledronic acid groups at both the 4th- and 12th-week time points in the mandible. These data collectively suggest that ovariectomized causes bone mass loss by enhancing apoptosis of osteoblasts and inhibiting apoptosis of osteoclasts. In osteoclasts, these cellular effects may be achieved by activating RANKL-NF-κB signalling. Moreover, zoledronic acid elicits its therapeutic effects in the mandible by counteracting these cellular and molecular consequences of ovariectomized.


Assuntos
Apoptose/efeitos dos fármacos , NF-kappa B/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Ácido Zoledrônico/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Diferenciação Celular/efeitos dos fármacos , Feminino , NF-kappa B/metabolismo , Osteoclastos/patologia , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Ovariectomia/métodos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
10.
J Biomater Appl ; 35(4-5): 544-552, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32660363

RESUMO

Porous titanium scaffolds can provide sufficient mechanical support and bone growth space for large segmental bone defect repair. However, they fail to restore the physiological environment of bone tissue. Barium titanate (BaTiO3) is considered a smart material that can produce an electric field in response to dynamic force. Low-intensity pulsed ultrasound stimulation (LIPUS), as a kind of micromechanical wave, can not only promote bone repair but also induce BaTiO3 to generate an electric field. In our studies, BaTiO3 was coated on porous Ti6Al4V and LIPUS was externally applied to observe the influence of the piezoelectric effect on the repair of large bone defects in vitro and in vivo. The results show that the piezoelectric effect can effectively promote the osteogenic differentiation of bone marrow stromal cells (BMSCs) in vitro as well as bone formation and growth into implants in vivo. This study provides an optional alternative to the conventional porous Ti6Al4V scaffold with enhanced osteogenesis and osseointegration for the repair of large bone defects.


Assuntos
Ligas/química , Compostos de Bário/química , Osso e Ossos/química , Materiais Revestidos Biocompatíveis/química , Alicerces Teciduais/química , Titânio/química , Animais , Compostos de Bário/metabolismo , Osso e Ossos/metabolismo , Diferenciação Celular , Materiais Revestidos Biocompatíveis/metabolismo , Humanos , Testes Mecânicos , Células-Tronco Mesenquimais , Osseointegração , Osteogênese , Porosidade , Ovinos , Engenharia Tecidual , Titânio/metabolismo , Microtomografia por Raio-X
11.
Zhonghua Yi Xue Za Zhi ; 88(35): 2482-6, 2008 Sep 16.
Artigo em Zh | MEDLINE | ID: mdl-19080629

RESUMO

OBJECTIVE: To evaluate the effects of perioperative oral administration of Yunan Baiyao on reduction of postoperative facial swelling following bimaxillary orthognathic surgery. METHODS: Patients scheduled for Le Fort I osteotomies and bilateral sagittal split ramus osteotomies were enrolled in the prospective, randomized, double-blind, placebo-controlled clinical study. Patients were orally administrated with Yunnan Baiyao capsules or placebo capsules before 3 days of operation and 5 days post-operation. Three-dimensional face images were recorded with OKIO-SC-400 Scanning System in 40 patients at pre-operation, postoperatively 3 day, 1 week and 1 month. Facial scans from different time periods were registrated to same coordinates and overlaid onto the baseline facial scan. 3D and 2D model deviations were performed with reverse engineering software to compare the differences between each two models and to quantitatively determine the reductions in facial swelling. RESULTS: There were 18 patients in Yunnan Baiyao group and 22 patients in control group. The severe swelling region was in the cheek, followed by the upper and lower lip. The average reduction of swelling thickness in Yunnan Baiyao group and control group from 3 day to 1 week postoperative was 3.6 mm and 2.3 mm respectively; there was significant difference between the two groups. Significant differences were also found in percentage changes of facial morphology from 3 day to 1 week postoperative (49.0% and 38.3% respectively). There were no significant changes in facial volumes of swelling between the two groups. CONCLUSIONS: Perioperative oral administration of Yunnan Baiyao capsules can effectively reduce the magnitude of facial swelling in bimaxillary orthognathic surgery. Yunnan Biayao has efficacy of anti-inflammatory response.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Edema/tratamento farmacológico , Fitoterapia , Complicações Pós-Operatórias/tratamento farmacológico , Método Duplo-Cego , Face , Feminino , Humanos , Masculino , Procedimentos Cirúrgicos Bucais/efeitos adversos , Placebos
12.
Zhonghua Yi Xue Za Zhi ; 88(33): 2339-42, 2008 Aug 26.
Artigo em Zh | MEDLINE | ID: mdl-19087695

RESUMO

OBJECTIVE: To evaluate the effects of Yunnan Baiyao capsules on facial swelling and anti-inflammatory response after orthognathic surgery. METHODS: 87 patients scheduled for Le Fort I osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) and genioplasty were randomly divided into 2 groups: experiment roup (n = 43) given with Yunnan Baiyao capsules orally 4 days before operation once daily and then via nasal feeding tube after operation once a day for 5 days, and placebo group given with placebo capsules. Antibiotic was routinely given to both groups. Serum levels of C-reactive protein (CRP), interleukin 6 (IL-6), and IL-1 were quantified on postoperative days 1, 2, 3, and 5. Degrees of facial swelling were evaluated on postoperative days 3, 5, and 7. RESULTS: Peak CRP and cytokines levels were reached on the first postoperative day in both groups, and the the variables decreased. The serum concentrations of CRP and IL-6 in the Yunan Baiyao group were lower than those in the control group. The CRP levels on the postoperative day 2, 3 and 5 of the experiment group were all significantly lower than those of the placebo group, and the IL-6 level on the second postoperative day of the experiment group was significantly lower than that of the placebo group. CONCLUSION: Perioperative administration of Yunnan Baiyao capsules can reduce the magnitude of inflammatory response and facial swelling after orthognathic surgery. Yunnan Baiyao capsule has efficacy of anti-inflammatory response.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Inflamação/tratamento farmacológico , Fitoterapia , Complicações Pós-Operatórias/tratamento farmacológico , Adolescente , Adulto , Proteína C-Reativa/metabolismo , Cápsulas , Método Duplo-Cego , Edema/tratamento farmacológico , Edema/etiologia , Feminino , Humanos , Inflamação/sangue , Interleucina-1/sangue , Interleucina-6/sangue , Masculino , Procedimentos Cirúrgicos Bucais/efeitos adversos , Placebos , Complicações Pós-Operatórias/sangue , Estudos Prospectivos
13.
Biomaterials ; 27(25): 4409-18, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16677705

RESUMO

Poly(epsilon-caprolactone) (PCL) film was modified using specified amounts of poly(d,l-lactide-co-glycolide) (PLGA) to provide a means to control polymer degradation. The aim of the study was to determine the effects of doping PCL with PLGA on the materials degradation, morphology and cell adhesion, to determine the significant variables within the process that could provide further control of cell adhesion. PLGA-doped PCL films were aged in osteogenic medium at 37 degrees C for up to 28 days. The aged samples were analysed in terms of weight loss or weight gain, molecule deposition and surface morphology. Molecule deposition was determined using Fourier transform infrared spectroscopy in attenuated total reflectance mode (FTIR-ATR) and morphology was determined using scanning electron microscopy and interferometric microscopy. The loss of the PLGA doping during degradation enhanced the formation of nano-porous structures in the remaining PCL domains, which attracted the deposition of substances from the osteogenic medium, which favoured the attachment and growth of human osteoblasts. The growth of osteoblasts was influenced by the controlled release of acidic products through polymer blending. Two pairs of FTIR-ATR absorption bands at 1090 and 1110 cm(-1), and at 1180 and 1190 cm(-1) were found to correlate to both PLGA and PCL, respectively. Changing the level of PLGA doping in PCL provided an approach to control the acidic products which can direct the growth of osteoblast cells.


Assuntos
Caproatos , Adesão Celular , Proliferação de Células , Ácido Láctico , Lactonas , Osteoblastos/citologia , Ácido Poliglicólico , Polímeros , Células Cultivadas , Microscopia Eletrônica de Varredura , Osteoblastos/ultraestrutura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Infravermelho com Transformada de Fourier
14.
Plast Reconstr Surg ; 137(2): 347e-354e, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26818325

RESUMO

BACKGROUND: The administration of different doses of parathyroid hormone to promote mandibular distraction osteogenesis remains unclear. The objective of the present study was to examine the effects of recombinant human parathyroid hormone on new bone formation during mandibular distraction osteogenesis and to investigate the dose-effect relationship associated with this phenomenon. METHODS: A total of 45 rabbits were used to establish the mandibular distraction osteogenesis model. The rabbits were divided into a control group (that received a subcutaneous injection of 1 ml of saline every other day) and experimental groups A, B, C, and D (that received subcutaneous injections of 10, 20, 30, and 40 µg/kg of recombinant human parathyroid hormone, respectively, every other day). On days 1, 7, and 14 of the consolidation period after the distraction had been completed, new bone in the distraction region was examined through histomorphometric investigation and bone mineral density testing. RESULTS: On days 1, 7, and 14 of the fixation period, the number of osteoblasts, trabecular bone area, and bone mineral density were greater in each experimental group than in the control group. On day 1 of the consolidation period, group C featured the highest average number of osteoblasts. On day 14 of the consolidation period, group C exhibited the highest bone mineral densities and largest trabecular bone areas. CONCLUSIONS: Intermittent subcutaneous injections of recombinant human parathyroid hormone can promote new bone formation during mandibular distraction osteogenesis. Different doses of recombinant human parathyroid hormone promoted mandibular distraction osteogenesis to differing extents.


Assuntos
Mandíbula/efeitos dos fármacos , Mandíbula/crescimento & desenvolvimento , Osteogênese/efeitos dos fármacos , Hormônio Paratireóideo/administração & dosagem , Animais , Densidade Óssea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Mandíbula/cirurgia , Osteogênese por Distração , Coelhos , Proteínas Recombinantes/administração & dosagem
15.
Rev Inst Med Trop Sao Paulo ; 57(3): 273-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26200971

RESUMO

Deep Candida infections commonly occur in immunosuppressed patients. A rare case of a multiple deep organ infection with Candida albicans and spinal tuberculosis was reported in a healthy young man. The 19-year-old man complained of month-long fever and lower back pain. He also had a history of scalded mouth syndrome. Coinfection with Mycobacterium tuberculosis and Candida albicans was diagnosed using the culture of aspirates from different regions. Symptoms improved considerably after antifungal and antituberculous therapy. This case illustrates that infection with tuberculosis might impair the host's immune system and increase the risk of invasive candidiasis in an immunocompetent patient.


Assuntos
Candidíase Invasiva/complicações , Tuberculose da Coluna Vertebral/complicações , Candidíase Invasiva/diagnóstico , Humanos , Imunocompetência , Masculino , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/imunologia , Adulto Jovem
16.
Chin J Traumatol ; 7(2): 81-6, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15294125

RESUMO

OBJECTIVE: To study the effect of nerve growth factor (NGF) and Schwann cells on axon regeneration of the inferior alveolar nerve following mandibular lengthening with distraction osteogenesis. METHODS: Unilateral mandibular osteodistraction was performed in 9 healthy adult male goats with a distraction rate of 1 mm/d. Every 3 goats were killed on days 7, 14 and 28 after mandibular lengthening, respectively. The inferior alveolar nerves in the distraction callus were harvested and processed for ultrastructural and NGF immunohistochemical study. The inferior alveolar nerves from the contralateral side were used as controls. RESULTS: On day 7 after distraction, axon degeneration and Schwann cell proliferation were observed, and very strong staining of NGF in the distracted nerve was detected. On day 14 after distraction, axon regeneration and remyelination were easily observed, and NGF expression started to decline. On day 28 after distraction, the gray scale of NGF immunoreactivity recovered to the normal value and the Schwann cells almost recovered to their normal state. CONCLUSIONS: Gradual mandibular osteodistraction can result in mild or moderate axon degeneration of the inferior alveolar nerve. Nerve trauma may stimulate the proliferation of Schwann cells and promote the synthesis and secretion of NGF in the Schwann cells. Schwann cells and NGF might play important roles in axon regeneration of the injured inferior alveolar nerve following mandibular lengthening.


Assuntos
Axônios/fisiologia , Mandíbula/cirurgia , Nervo Mandibular/fisiologia , Fator de Crescimento Neural/fisiologia , Regeneração Nervosa/fisiologia , Osteogênese por Distração , Células de Schwann/fisiologia , Animais , Axônios/patologia , Cabras , Imuno-Histoquímica , Masculino
17.
Arch Oral Biol ; 59(9): 906-11, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24907520

RESUMO

Dental age estimation is of great importance for individual identification in forensic medicine and many other fields of study. Among them, tooth eruption is a parameter developmental morphology that can be determined by clinical examinations or by dental X-rays. The purpose of present research is to study the chronological course of third molars eruption in a Chinese population and compare that with other ethnic population for age estimation. A total of 1135 conventional orthopantomograms from 506 male and 629 female northern Chinese subjects aged between 11 and 26 years were analyzed. The eruption status of the third molars was assessed using the developmental stages described by Olze et al. Results showed that the third molars 18, 28, 38 and 48 in the stage A showed significant younger average age in males than in females. The Olze's stage A could be used as a reference stage to determine whether a male or female northern Chinese is likely to be equal or above age 16, with 99.6-100% and 97.4-98.1% of correct predictions, respectively. The stage D was found to be a useful marker for diagnosing age under 16 years, with 98.9-100% and 100% of correct predictions in males and females, respectively. There were some significant differences of the chronological course of the third molars eruption in different ethnic groups, which indicated that population-specific standards could enhance the accuracy of forensic age estimation based on third molar eruption.


Assuntos
Determinação da Idade pelos Dentes/métodos , Odontologia Legal/métodos , Dente Serotino/crescimento & desenvolvimento , Erupção Dentária , Adolescente , Adulto , Povo Asiático , Criança , China , Feminino , Humanos , Masculino , Dente Serotino/diagnóstico por imagem , Radiografia Panorâmica , Caracteres Sexuais , Fatores de Tempo
18.
Adv Mater ; 24(4): 554-8, 2012 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-22250035

RESUMO

Inverted polymer solar cells with a bottom metal cathode modified by a conjugated polymer interlayer show considerable improvement of photocurrent and fill factor, which is due to hole blocking at the interlayer, and a modified surface energy which affects the nanostructure in the TQ1/[70]PCBM blend.


Assuntos
Fontes de Energia Elétrica , Polímeros/química , Energia Solar , Eletrodos , Compostos de Estanho/química
19.
Rev. Inst. Med. Trop. Säo Paulo ; 57(3): 273-275, May-Jun/2015. graf
Artigo em Inglês | LILACS | ID: lil-752602

RESUMO

Deep Candida infections commonly occur in immunosuppressed patients. A rare case of a multiple deep organ infection with Candida albicans and spinal tuberculosis was reported in a healthy young man. The 19-year-old man complained of month-long fever and lower back pain. He also had a history of scalded mouth syndrome. Coinfection with Mycobacterium tuberculosis and Candida albicans was diagnosed using the culture of aspirates from different regions. Symptoms improved considerably after antifungal and antituberculous therapy. This case illustrates that infection with tuberculosis might impair the host's immune system and increase the risk of invasive candidiasis in an immunocompetent patient.


As infecções profundas por Candida ocorrem geralmente em pacientes imunossuprimidos. Relatamos caso raro de infecções profundas em múltiplos órgãos por Candida albicans e neuro tuberculose em homem jovem saudável. Um jovem de 19 anos de idade queixou-se de febre e lombalgia há um mês. Relatava ainda histórico de síndrome da boca escaldada. Foi diagnosticada co-infecção por Mycobacterium tuberculosis e Candida albicans em cultura do aspirado de diferentes regiões do organismo. Os sintomas melhoraram significativamente após a terapia antifúngica e antituberculosa. Este caso é apresentado para mostrar que a tuberculose pode prejudicar o sistema imune do hospedeiro e aumentar o risco de candidíase invasiva em paciente imunocompetente.


Assuntos
Humanos , Masculino , Adulto Jovem , Candidíase Invasiva/complicações , Tuberculose da Coluna Vertebral/complicações , Candidíase Invasiva/diagnóstico , Imunocompetência , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/imunologia
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(9): 542-5, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19087606

RESUMO

OBJECTIVE: To evaluate the haemostatic efficacy and safety of prophylactic oral administration of Yunan Baiyao capsules on reduction of blood loss in bimaxillary orthognathic surgery. METHODS: Eighty-seven patients scheduled for Le Fort I osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) were enrolled in the prospective, randomized, double-blind, placebo-controlled clinical study. Forty-three patients took prophylactic oral administration of Yunnan Baiyao capsules 3 days before operation, and 44 patients without Yunnan Baiyao administration served as control. The intraoperative blood loss during Le Fort I osteotomy and bilateral sagittal split ramus osteotomy was estimated and the safety of Yunnan Baiyao capsules was evaluated. RESULTS: The total blood loss in the Yunnan Baiyao group (330.5 +/- 134.4) ml was significantly lower than that of the control group (420.3 +/- 175.9) ml. The blood loss of Le Fort I osteotomy in the Yunnan Baiyao group (154.9 +/- 84.3) ml was also significantly lower than that of the control group (203.8 +/- 98.1) ml. The mean blood loss of BSSRO in the Yunnan Baiyao group was also lower than that of the control group, but the differences was not significant. The post-operative fibrinolysis was in the same level in both groups. Thromboemblic events or other side effects were not observed in this clinical trial. CONCLUSIONS: Prophylactic oral administration of Yunnan Baiyao capsules can effectively reduce the intra-operative blood loss in bimaxillary orthognathic surgery. Yunnan Baiyao capsule are an effective and safe haemostatic traditional Chinese medicine.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Medicamentos de Ervas Chinesas/uso terapêutico , Cirurgia Ortognática/métodos , Fitoterapia , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Estudos Prospectivos , Adulto Jovem
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