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1.
J Bone Oncol ; 34: 100425, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35391944

RESUMO

Bone metastases is a common manifestation of advanced malignant tumors. With the recent advances in medical technology, the survival period of patients with malignant tumors is prolonged, and the probability of bone metastases is significantly increased. Approximately 70% to 80% of patients with breast or prostate cancer will eventually develop bone metastases. In addition, thyroid, lung, and kidney carcinomas are all known to cause bone metastases, with a 30% to 40% incidence upon postmortem assessment. Bone metastases often lead to severe pain, pathological fractures, and nerve damage and have become a critical factor affecting the quality of life and life expectancy of cancer patients. Although treatments for bone metastases are diverse, choosing the appropriate treatment is difficult. Both conservative treatment and open surgery have certain drawbacks and may not be appropriate for all patients. Interventional procedures have the advantages of less trauma with quicker recovery and represent a viable alternative. This review provides updates on the progress of research on the interventional treatment of bone metastases and directions regarding relevant further studies.

2.
BMC Musculoskelet Disord ; 22(1): 304, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771141

RESUMO

BACKGROUND: Heterotopic ossification (HO) is noted most frequently in periarticular muscles and has not yet been reported in the cruciate ligaments of the knee. We present a rare case of symptomatic ossification of the posterior cruciate ligament (PCL). CASE PRESENTATION: A 59-year-old woman had a 2-year history of knee pain that was getting worse during knee motion and had restricted knee motion for 1 year. X-rays could not show the lesion clearly. Multi-planar computed tomography demonstrated ossification within the PCL with mild osteoarthritic changes and excluded any other intra-articular pathology. The patient underwent arthroscopic debridement and then experienced immediate relief of pain and complete recovery of range of motion. CONCLUSION: This is the first report of HO in the PCL as a possible cause of knee pain and restricted knee motion. On the basis of literature review, this case elaborates the difference between HO and calcification in the ligaments, the related factors inducing HO and the undefined pathogenesis, and favorable prognosis after adequate treatment.


Assuntos
Ossificação Heterotópica , Ligamento Cruzado Posterior , Artroscopia , Feminino , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Ligamentos Articulares , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/cirurgia , Ligamento Cruzado Posterior/diagnóstico por imagem , Ligamento Cruzado Posterior/cirurgia , Amplitude de Movimento Articular
3.
ACS Omega ; 2(5): 1886-1895, 2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457549

RESUMO

Biocompatible and biodegradable polylactide (PLA) composites with supertough mechanical property and sufficient flame retardancy were fabricated by employing a facile approach involving reactive blending of PLA and ethylene-acrylic ester-glycidyl methacrylate terpolymer (EGMA), with the addition of aluminum hypophosphite (AHP) as an effective flame retardant. In consideration of the balance between mechanical property and flame retardancy, the optimal formula was taking a PLA/EGMA 80/20 blend (supertough STPLA) as the matrix and adding 20 wt % of AHP (relative to the mass of STPLA) as the flame retardant, coded as STPLA/20AHP. The mechanical property test showed that for STPLA/20AHP the elongation at break was increased by about 22 times and the notched Izod impact strength was enhanced by approximately 11 times as compared to those for neat PLA. The flame-retardant property test showed that for STPLA/20AHP the limiting oxygen index value reached 26.6% and the UL-94 V0 rating test was passed. Thermogravimetric analysis, microscale combustion calorimetry, and cone calorimeter were further applied to reveal the thermal stability and combustion behaviors of STPLA/xAHP, respectively, where x indicated the mass content of AHP in percentage. The phase separation morphology, dispersion of AHP particles in STPLA matrix, and fracture surfaces and char residues after flame burning were examined by phase contrast optical microscopy and scanning electron microscopy, respectively, which helped comprehend the results obtained from the mechanical property and flame retardancy tests. The supertough STPLA/xAHP, with sufficient flame retardancy as prepared in this work, could have a potential for engineering applications.

4.
ACS Appl Mater Interfaces ; 6(16): 13552-63, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25105468

RESUMO

Supertough biocompatible and biodegradable polylactide materials were fabricated by applying a novel and facile method involving reactive blending of polylactide (PLA) and poly(ethylene glycol) diacylate (PEGDA) monomer with no addition of exogenous radical initiators. Torque analysis and FT-IR spectra confirm that cross-linking reaction of acylate groups occurs in the melt blending process according to the free radical polymerization mechanism. The results from differential scanning calorimetry, phase contrast optical microscopy and transmission electron microscopy indicate that the in situ polymerization of PEGDA leads to a phase separated morphology with cross-linked PEGDA (CPEGDA) as the dispersed particle phase domains and PLA matrix as the continuous phase, which leads to increasing viscosity and elasticity with increasing CPEGDA content and a rheological percolation CPEGDA content of 15 wt %. Mechanical properties of the PLA materials are improved significantly, for example, exhibiting improvements by a factor of 20 in tensile toughness and a factor of 26 in notched Izod impact strength at the optimum CPEGDA content. The improvement of toughness in PLA/CPEGDA blends is ascribed to the jointly contributions of crazing and shear yielding during deformation. The toughening strategy in fabricating supertoughened PLA materials in this work is accomplished using biocompatible PEG-based polymer as the toughening modifier with no toxic radical initiators involved in the processing, which has a potential for biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Fenômenos Mecânicos , Poliésteres/química , Polietilenoglicóis/química , Varredura Diferencial de Calorimetria , Reagentes de Ligações Cruzadas/química , Cristalização , Módulo de Elasticidade , Microscopia Eletrônica de Transmissão , Peso Molecular , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Resistência à Tração , Viscosidade
5.
Food Chem ; 141(1): 66-71, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23768328

RESUMO

A new method was developed for the determination of organic and inorganic selenium in selenium-enriched rice by graphite furnace atomic absorption spectrometry detection after cloud point extraction. Effective separation of organic and inorganic selenium in selenium-enriched rice was achieved by sequentially extracting with water and cyclohexane. Under the optimised conditions, the limit of detection (LOD) was 0.08 µg L(-1), the relative standard deviation (RSD) was 2.1% (c=10.0 µg L(-1), n=11), and the enrichment factor for selenium was 82. Recoveries of inorganic selenium in the selenium-enriched rice samples were between 90.3% and 106.0%. The proposed method was successfully applied for the determination of organic and inorganic selenium as well as total selenium in selenium-enriched rice.


Assuntos
Fracionamento Químico/métodos , Oryza/química , Selênio/análise , Selênio/isolamento & purificação , Espectrofotometria Atômica/métodos
6.
Talanta ; 106: 8-13, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23598089

RESUMO

A new method was developed for the speciation analysis of inorganic arsenic in coal samples by high performance liquid chromatography coupled to hydride generation atomic fluorescence spectrometry after microwave-assisted extraction. Effective extract of As(III) and As(V) in coal sample was achieved by 1.0 mol L(-1)H3PO4 and 0.1 mol L(-1)ascorbic acid. Under the optimized conditions, the limits of detection (LOD) were 0.01 µg L(-1) and 0.02 µg L(-1), the relative standard deviations (RSD) were 2.4% and 3.3% (c=10.0 µg L(-1), n=7), recoveries were 102.5% and 96.5% for As(III) and As(V). The proposed method was successfully applied for the determination of speciation of inorganic arsenic in coal samples and GBW11117 coal standard reference material with complex matrix.

7.
Arthritis Rheum ; 64(10): 3324-33, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22674034

RESUMO

OBJECTIVE: To study the regulation of expression of ß-1,3-glucuronosyltransferase 1 (GlcAT-1), an important regulator of glycosaminoglycan (GAG) synthesis, by Smad3 in nucleus pulposus (NP) cells. METHODS: GlcAT-1 expression was examined in rat NP and anulus fibrosus (AF) cells treated with transforming growth factor ß (TGFß). The effects of Smad signaling and Smad suppression on GlcAT-1 were examined in rat NP cells. GlcAT-1 expression was analyzed in the discs of Smad3-null mice and in degenerated human NP tissue. RESULTS: TGFß increased the expression of GlcAT-1 in rat NP but not rat AF cells. Suppression of GlcAT-1 promoter activity was evident with dominant-negative ALK-5 (DN-ALK-5). Cotransfection with Smad3 strongly induced promoter activity independent of TGFß. Bioinformatics analysis indicated the presence of several Smad binding sites in the promoter; deletion analysis showed that the region between -274 and -123 bp was required for Smad3 response. DN-Smad3, Smad 3 small interfering RNA, and Smad7 strongly suppressed basal as well as TGFß-induced promoter activity. Induction of promoter activity by Smad3 was significantly blocked by DN-Smad3; Smad7 had a very small effect. Lentiviral transduction of NP cells with short hairpin RNA Smad3 resulted in a decrease in GlcAT-1 expression and accumulation of GAG. Compared to wild-type mice, significantly lower expression of GlcAT-1 was seen in the discs of Smad3-null mice. Analysis of degenerated human NP tissue specimens showed no positive correlation between GlcAT-1 and TGFß expression. Moreover, isolated cells from degenerated human tissue showed a lack of induction of GlcAT-1 expression following TGFß treatment, suggesting an altered response. CONCLUSION: Our findings demonstrate that in healthy NP cells, the TGFß-Smad3 axis serves as a regulator of GlcAT-1 expression. However, an altered responsiveness to TGFß during disc degeneration may compromise GAG synthesis.


Assuntos
Glucuronosiltransferase/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Disco Intervertebral/metabolismo , Proteína Smad3/metabolismo , Animais , Expressão Gênica/efeitos dos fármacos , Glucuronosiltransferase/genética , Humanos , Disco Intervertebral/efeitos dos fármacos , Degeneração do Disco Intervertebral/genética , Camundongos , Camundongos Knockout , Fosforilação , Regiões Promotoras Genéticas/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/genética , Fator de Crescimento Transformador beta/farmacologia
8.
J Pharm Biomed Anal ; 60: 14-8, 2012 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-22118996

RESUMO

A cloud point extraction (CPE) method for the preconcentration of ultra-trace chromium speciation in human serum samples prior to determination by graphite furnace atomic absorption spectrometry (GFAAS) had been developed in this paper. In this method, Cr(III) reacts with 1-(2-pyridylazo)-2-naphthol (PAN) yielding a hydrophobic complex, which is then entrapped in the surfactant-rich phase, whereas Cr(VI) remained in aqueous phase. Thus, separation of Cr(III) and Cr(VI) could be realized. Total chromium was determined after the reduction of Cr(VI) to Cr(III) by using ascorbic acid as reducing reagent. PAN was used not only as chelating reagent in CPE, but also as chemical modifier in GFAAS. Triton X-114 non-ionic surfactant had been used as an extraction medium. The main factors affecting CPE efficiency, such as pH of solution, concentration and kind of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time, were investigated in detail. An enrichment factor of 83.5 was obtained for the preconcentration of Cr(III) with 10 mL solution. Under the optimal conditions, the detection limit of Cr(III) was 0.02 µg L⁻¹. The relative standard deviation was 2.6% for intra-day assay precision (n=7, c=10 ng mL⁻¹), values of recovery for chromium were from 92.0% to 94.7% for three samples. This method is simple, accurate, and sensitive and can be applied to determine ultra-trace chromium speciation in human serum.


Assuntos
Cromo/sangue , Extração Líquido-Líquido/métodos , Espectrofotometria Atômica/métodos , Quelantes/química , Cromo/química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Extração Líquido-Líquido/estatística & dados numéricos , Naftóis/química , Octoxinol , Polietilenoglicóis/química , Espectrofotometria Atômica/estatística & dados numéricos , Tensoativos/química , Temperatura
9.
J Hazard Mater ; 192(3): 935-9, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21824726

RESUMO

A cloud point extraction method for the preconcentration of ultra-trace bismuth in human serum prior to its determination by inductively coupled plasma optical emission spectrometry had been developed in this paper. The cloud point extraction method was based on the complex of Bi(III) with 8-hydroxyquinoline and Triton X-114 was used as non-ionic surfactant. The main factors affecting cloud point extraction efficiency, such as pH of solution, concentration of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time were investigated in detail. An enrichment factor of 81 was obtained for the preconcentration of Bi(III) with 25 mL solution. Under the optimal conditions, the detection limit of Bi(III) is 0.12 µg L(-1). The relative standard deviation (n = 7) of determination was 2.3%, values of recovery of bismuth were from 92.3% to 94.7% for three samples. This method is simple, accurate, sensitive and can be applied to the determination trace bismuth in human serum.


Assuntos
Bismuto/sangue , Técnicas de Química Analítica/métodos , Espectrofotometria/métodos , Humanos , Concentração de Íons de Hidrogênio , Íons , Metais/química , Octoxinol , Oxiquinolina/farmacologia , Polietilenoglicóis/farmacologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Soro/química , Tensoativos/química , Temperatura , Oligoelementos/sangue
10.
J Hazard Mater ; 176(1-3): 901-5, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20006436

RESUMO

A cloud point extraction (CPE) method for the preconcentration of ultra-trace aluminum in human albumin prior to its determination by graphite furnace atomic absorption spectrometry (GFAAS) had been developed in this paper. The CPE method was based on the complex of Al(III) with 1-(2-pyridylazo)-2-naphthol (PAN) and Triton X-114 was used as non-ionic surfactant. The main factors affecting cloud point extraction efficiency, such as pH of solution, concentration and kind of complexing agent, concentration of non-ionic surfactant, equilibration temperature and time, were investigated in detail. An enrichment factor of 34.8 was obtained for the preconcentration of Al(III) with 10 mL solution. Under the optimal conditions, the detection limit of Al(III) was 0.06 ng mL(-1). The relative standard deviation (n=7) of sample was 3.6%, values of recovery of aluminum were changed from 92.3% to 94.7% for three samples. This method is simple, accurate, sensitive and can be applied to the determination of ultra-trace aluminum in human albumin.


Assuntos
Albuminas/metabolismo , Alumínio/análise , Espectrofotometria Atômica/métodos , Precipitação Química , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Ligação Proteica , Reprodutibilidade dos Testes , Espectrofotometria Atômica/normas , Tensoativos/química
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