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1.
Food Chem ; 337: 127761, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777565

RESUMO

Amino and thiolated aptamers are the main aptamers used to construct label-free electrochemical impedimetric aptasensors. In this study, the modification performance and electrochemical properties of amino aptamers and thiolated aptamers were studied in the construction of label-free impedimetric sensors. The results showed that the initial modification density of amino aptamers was higher than that of thiol aptamers. Aptamers can recognize and bind OTA to generate electrical signals. The higher the density of aptamer modification was, the better the electric signals were. If only considering the initial modification density, amino aptamers were more suitable for the preparation of aptasensors than thiolated aptamers. However, the modification density of the amino aptamer decreased with the prolonged immersion time in 1 mM HCl solution, which suggests that the stability of this sensor was poor. However, the thiolated aptamer maintained relatively constant density and could be reused. Thus, the thiolated aptasensor had a wide range and good reproducibility and stability for the determination of ochratoxin A (OTA). In addition, this study proved that gold nanoparticles play an important role in signal amplification by increasing the effective gold surface to fix more aptamers in the process of sensor preparation.

2.
Cell Biol Int ; 43(5): 565-573, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30958604

RESUMO

Heterotopic ossification (HO) is a common disturbing complication of intra-articular fractures. Its prevention and treatment are still difficult as its pathogenesis is unclear. It was reported that PDGFRα+ muscle cells in skeletal muscle may participate in the formation of HO; however, the specific mechanism is still unknown. This study investigated the function of miR-19b-3p in osteogenic differentiation of PDGFRα+ muscle cells. MiR-19b-3p was upregulated during PDGFRα+ muscle cell osteogenic differentiation. The exogenous expression of miR-19b-3p led to an increase in osteogenic marker gene transcription and translation during the osteogenic differentiation of PDGFRα+ muscle cells. Furthermore, both alkaline phosphatase and alizarin red staining increased in miR-19b-3p mimic transfected cells. Over-expression of miR-19b-3p led to the down-regulation of gene of phosphate and tension homology deleted on chromosome ten (PTEN). Additionally, the dual luciferase reporter assay demonstrated that PTEN was a direct target of miR-19b-3p. The increase of osteocalcin, osteopontin, and Runt-related transcription factor 2 protein levels induced by ectopic miR-19b-3p expression could be partially reversed by PTEN over-expression. In conclusion, our results suggested that miR-19b-3p may be a promising target in inhibiting PDGFRα+ muscle cell osteogenic differentiation and treatment of HO.


Assuntos
MicroRNAs/metabolismo , Ossificação Heterotópica/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Diferenciação Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação para Baixo , Humanos , MicroRNAs/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Ossificação Heterotópica/genética , Ossificação Heterotópica/patologia , Osteocalcina/metabolismo , PTEN Fosfo-Hidrolase/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética
3.
Sci Rep ; 8(1): 14058, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30232405

RESUMO

A highly selective fluorescent sensor H4L based on a bis(salamo)-type compound with two N2O2 chelating moieties as ionophore was successfully developed. Sensor H4L was found to have excellent selectivity for B4O72- over many other anions (Br-, CI-, CN-, CO32-, HCO3-, H2PO4-, HSO4-, NO3-, OAc-, S2O3-, SCN-, SO42-, Hcy (homocysteine) and H2O2), and it exhibited an approximately 150-fold enhancement of the fluorescence response to B4O72- in Tris-HCl buffer (DMF/H2O = 9:1, v/v, pH = 7) solutions. Significantly, its fluorescence intensity was enhanced in a linear fashion with increasing concentrations of B4O72-. The detection limit of sensor H4L towards B4O72- was 8.61 × 10-7 M. The test strips could conveniently, efficiently and simply detect B4O72- ions in Tris-HCl buffer (DMF/H2O = 9:1, v/v, pH = 7) solutions. Furthermore, sensor H4L showed excellent membrane permeability in living cells, and it was successfully used to monitor intracellular B4O72- by confocal luminescence imaging.


Assuntos
Boratos/análise , Corantes Fluorescentes/síntese química , Água/química , Técnicas Biossensoriais , Corantes Fluorescentes/química , Limite de Detecção , Microscopia Confocal , Estrutura Molecular
4.
Molecules ; 23(4)2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-29614741

RESUMO

[Co2(L)Ce(OAc)3(CH3CH2OH)]·1.5CH3OH∙0.5CH2Cl2, a heterotrinuclear Co(II)-Ce(III) bis(salamo)-type complex with a symmetric bi(salamo)-type ligand H4L and an acyclic naphthalenediol moiety, was designed, synthesized and characterized by elemental analyses, FT-IR, UV-Vis and fluorescence spectroscopy and X-ray crystallography. The X-ray crystallographic investigation revealed the heterotrinuclear complex consisted of two Co(II) atoms, one Ce(III) atom, one (L)4‒ unit, three µ2-acetate ions, one coordinated ethanol molecule, one and half crystallization methanol molecule and half crystallization dichloromethane molecule. Two Co(II) atoms located in the N2O2 coordination spheres, are both hexacoordinated, with slightly distorted octahedral geometries. The Ce(III) atom is nine-coordinated and located in the O6 cavity possesses a single square antiprismatic geometry. In addition, supramolecular interactions exist in the Co(II)-Ce(III) complex. Two infinite 2D supramolecular structures are built via intermolecular O-H···O, C-H···O and C-H···π interactions, respectively.


Assuntos
Cério/química , Cobalto/química , Complexos de Coordenação/síntese química , Oximas/química , Complexos de Coordenação/química , Cristalografia por Raios X , Fluorescência , Ligação de Hidrogênio , Ligantes , Espectrometria de Fluorescência
5.
J Int Med Res ; 45(4): 1394-1405, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28606024

RESUMO

Objective To analyze the effects of the acetabular fracture index (AFI) and other factors on the functional outcome of patients with acetabular fractures involving the posterior wall. Methods Forty-eight patients who underwent surgery in our department were reviewed. According to the AFI, which indicates the percentage of remaining intact posterior acetabular arc, the patients were divided into Group A (AFI ≤ 25%, 11 patients), Group B (25% < AFI ≤ 50%, 23 patients), Group C (50% < AFI ≤ 75%, 7 patients), and Group D (75% < AFI ≤ 100%, 7 patients). The AFI was measured with a computed tomography picture archiving and communication system or calculated with the cosine theorem. A nonparametric test and ordinal regression were used to determine the role of the AFI and other factors on the functional outcome. Perioperative information, including demographic and fracture-related data, reduction quality, physical therapy duration, association with a lower limb fracture and avascular necrosis of the femoral head were prospectively gathered. Results The mean AFIs of A, B, C, and D groups were 14.3%, 35.9%, 59.5%, and 81.2%, respectively. No statistically significant differences were observed among the groups for demographic and fracture-related data. A better reduction quality (OR = 4.21, 95%CI 1.42 ∼ 12.43, χ2 = 6.781, P = 0.009) and a larger value of AFI (OR = 2.56, 95%CI 1.18 ∼ 5.55, χ2 = 5.648, P = 0.017) result in a higher functional score. The functional outcome of a physical therapy duration of more than 12 months (OR = 0.15, 95%CI 0.02 ∼ 0.90, χ2 = 4.324, P = 0.038) was better than that of less than 12 months. Lower limb fracture (OR = 0.13, 95%CI 0.02 ∼ 0.74, χ2 = 5.235, P = 0.022) and avascular necrosis of femoral head (OR = 0.02, 95%CI 0.00 ∼ 0.87, χ2 = 4.127, P = 0.042) were found to correlate with a lower functional score. Conclusion With a greater of AFI, the functional outcome score would be better. Other factors, including reduction quality, physical therapy duration, association with a lower limb fracture, and avascular necrosis of the femoral head, most likely also affect hip functional recovery.


Assuntos
Acetábulo/lesões , Fraturas Ósseas/cirurgia , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Adolescente , Adulto , Idoso , Feminino , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Int J Clin Pharm ; 39(4): 826-830, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28500436

RESUMO

Background Heterotopic ossification (HO) after joint surgery is always a disturbing problem for patients and surgeons. Prophylaxis is the most effective therapy. Objective To assess the efficacy and safety of a multimodal analgesia protocol that included parecoxib and celecoxib in preventing HO after acetabular fracture surgery. Setting Selecting patients from trauma registry of our hospital. Method We identified 259 patients who had acetabular fracture surgery between January 2008 and December 2014. Hundredsixty-three patients received parecoxib and celecoxib (Group A) and 96 patients received no prophylaxis (Group B). The presence of HO was assessed according to the classification of Brooker et al. at the 12 month postoperative visit. Main outcome measure The differences in HO incidence and severity between the two groups. Results 49 patients (30.0%) developed HO in the Group A and 44(45.8%) in Group B. The difference in total HO incidence between the two groups was significant (P = 0.011 < 0.05, χ2 = 6.530, OR 0.508, 95% CI (0.301-0.857). Severe HO (Brooker grade III or IV) developed in 15 patients (9.2%) in Group A and 17 patients (17.7%) in Group B. Brooker grade I + II was 34(20.9%) and 27(28.1%) in each group. The difference in the severity of HO between the two Groups was significant (P = 0.008 < 0.05). Conclusion A short-term administration of parecoxib and celecoxib aids in the prevention of HO after acetabular fractures surgery.


Assuntos
Acetábulo/lesões , Acetábulo/cirurgia , Fraturas Ósseas/tratamento farmacológico , Fraturas Ósseas/cirurgia , Ossificação Heterotópica/prevenção & controle , Manejo da Dor/métodos , Adulto , Idoso , Analgesia/métodos , Celecoxib/administração & dosagem , Terapia Combinada/métodos , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Quimioterapia Combinada , Feminino , Fraturas Ósseas/diagnóstico , Humanos , Isoxazóis/administração & dosagem , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico , Ossificação Heterotópica/etiologia , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
7.
Plant Pathol J ; 32(2): 85-94, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27147928

RESUMO

Studies were conducted to determine the role of 3-methylthioproprionic acid (MTPA) in the pathogenicity of potato stem canker, Rhizoctonia solani, and the concentrations required to inhibit growth of R. solani under laboratory and plant house-based conditions. The experiments were laid out in a completely randomized design with five treatments and five replications. The treatments were 0, 1, 2, 4, and 8 mM concentrations of MTPA. The purified toxin exhibited maximal activity at pH 2.5 and 30°C. MTPA at 1, 2, 4, and 8 mM levels reduced plant height, chlorophyll content, haulm fresh weight, number of stolons, canopy development, and tuber weight of potato plants, as compared to the control. MTPA significantly affected mycelial growth with 8 mM causing the highest infection. The potato seedlings treated with MTPA concentrations of 1.0-8.0 mM induced necrosis of up to 80% of root system area. Cankers were resulted from the injection of potato seedling stems with 8.0 mM MTPA. The results showed the disappearance of cell membrane, rough mitochondrial and cell walls, change of the shape of chloroplasts, and swollen endoplasmic reticulum. Seventy-six (76) hours after toxin treatment, cell contents were completely broken, cytoplasm dissolved, and more chromatin were seen in the nucleus. The results suggested that high levels of the toxin concentration caused cell membrane and cytoplasm fracture. The integrity of cellular structure was destroyed by the phytotoxin. The concentrations of the phytotoxin were significantly correlated with pathogenicity and caused damage to the cell membrane of potato stem base tissue.

8.
Indian J Orthop ; 47(4): 395-401, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23960285

RESUMO

BACKGROUND: Several studies suggested that celecoxib interferes with bone healing while others contradict these findings. This study was conducted to investigate the effects of celecoxib on bone healing in rats femur mold with a dose based on body surface area conversion. MATERIALS AND METHODS: 72 adult female Sprague Dawley rats were randomly divided into three groups after the internal fixation operation of nondisplaced transverse mid diaphyseal fractures of the right femurs. Each group was treated with 1% methylcellulose, celecoxib (21 mg/kg/d) for 1 week, or celecoxib (21 mg/kg/d) for 4 weeks after surgeries respectively. Bone healing scores and callus formation were evaluated by radiographs at 3, 4, 6 weeks after surgeries. Half of these rats were sacrificed for histological analysis at 4 weeks after surgery. The remaining fractured femurs were evaluated by biomechanical tests at 6 weeks after surgery. RESULTS: The mean radiographic scores for fracture healing of both short and long term groups were lower than that of the control group and the differences among the three groups were statistically significant (P < 0.05) at 3, 4, 6 weeks after surgery. The mean bone trabecula density of both groups was smaller than that of the control group and the differences were also statistically significant (P < 0.05) at 4 week. The maximum load, total energy and stiffness in both the short term and long term groups were significantly decreased compared with those in the control group (P < 0.05) at 6 week. CONCLUSION: Both short term and long term sustained use of celecoxib in rat models has significantly inhibitory effects on rat fracture healing.

9.
Clin Orthop Relat Res ; 467(10): 2738-43, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19459023

RESUMO

Melorheostosis is a rare, noninheritable bone dysplasia characterized by its classic radiographic feature of flowing hyperostosis resembling dripping candle wax, generally on one side of the long bone. The condition originally was described by Leri and Joanny in 1922. Its etiology remains speculative, and treatment in most instances has been symptomatic. Melorheostosis usually affects one limb, more often the lower extremity, and rarely the axial skeleton. We report a rare case of severe melorheostosis in the ipsilateral upper and lower extremities with normal contralateral extremities. The plain radiographs revealed almost all the bones in the affected extremities, from clavicle and scapula to distal phalanges of the fingers and from femur to distal phalanges of the toes, presented extensive, dense hyperostosis and heterotopic ossification in the periarticular soft tissue. Physical examination showed considerable swelling and deformities of the left limbs, stiffness and distortion of the joints, and anesthesia in the left ulnar regions of the forearm and hand. The examination of the right side was normal. Computed tomography scans showed multiple areas of classic candle wax-like hyperostosis and narrowing or disappearance of the medullary cavity. Histologic analysis confirmed the clinical and imaging diagnosis and revealed extremely dense sclerotic bone of cortical pattern.


Assuntos
Osso e Ossos , Melorreostose/diagnóstico , Adulto , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Osso e Ossos/fisiopatologia , Progressão da Doença , Edema/etiologia , Extremidades , Feminino , Humanos , Melorreostose/complicações , Melorreostose/tratamento farmacológico , Melorreostose/fisiopatologia , Dor/etiologia , Exame Físico , Amplitude de Movimento Articular , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Resultado do Tratamento
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