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1.
Calcif Tissue Int ; 113(4): 383-392, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37493798

RESUMO

In this study, we aim to evaluate the correlation between T score measured by dual X-ray absorptiometry (DXA), volumetric bone mineral density (vBMD) derived from quantitative computed tomography (QCT) and MRI-based vertebral bone quality (VBQ), explore the diagnostic performance of VBQ in osteoporosis and determine the recognition value of VBQ in osteoporotic fracture in a relatively large cohort of elderly patients scheduled to undergo spinal surgery. A total of 260 patients were enrolled in the study. DXA and QCT were used to evaluate osteoporotic status. We calculated the lumbar VBQ score, analyzed the correlation between T score, vBMD and VBQ, and explored whether VBQ was an influential factor of bone quality and fracture by binary logistic regression as well as the diagnostic performance of VBQ in osteoporosis and fracture by ROC curve. VBQ was negatively correlated with vBMD and T score. (r = - 0.487 vs. r = - 0.220). The VBQ score was a risk factor for osteoporosis under the QCT diagnostic criteria (OR = 2.245, 95% CI 1.456-3.460) and osteoporotic fractures (OR = 1.496, 95% CI 1.097-2.040). It exhibited superior discriminant performance for osteoporosis diagnosed by QCT, with a cutoff value of 3.70 and an AUC of 0.7354. Its cutoff value for osteoporotic fractures was 3.72, and its AUC was 0.6717. In a cohort of elderly patients scheduled to undergo spinal surgery, the VBQ score was more strongly associated with vBMD than the T score and could identify patients with osteoporosis and corresponding vertebral compression fracture (VCF).


Assuntos
Fraturas por Compressão , Osteoporose , Fraturas por Osteoporose , Fraturas da Coluna Vertebral , Humanos , Idoso , Absorciometria de Fóton/métodos , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Compressão/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Densidade Óssea , Osteoporose/diagnóstico por imagem , Vértebras Lombares/lesões
2.
Spine J ; 23(8): 1172-1181, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37031891

RESUMO

BACKGROUND CONTEXT: Recently published studies have revealed a correlation between MRI-based vertebral bone quality (VBQ) score and bone mineral density (BMD) measured using dual X-ray absorptiometry (DXA) or quantitative computed tomography (QCT). However, no studies have determined if differences in field strength (1.5 vs 3.0 T) could affect the comparability of the VBQ score among different individuals. PURPOSE: To compare the VBQ score obtained from 1.5 T and 3.0 T MRI (VBQ1.5T vs VBQ3.0T) in patients undergoing spine surgery and assess the predictive performance of VBQ for osteoporosis and osteoporotic vertebral fracture (VCF). DESIGN: A nested case‒control study based on an ongoing prospective cohort study of patients undergoing spine surgery. PATIENT SAMPLE: All older patients (men aged >60 years and postmenopausal women) with available DXA, QCT and MR images within 1 month were included. OUTCOME MEASURES: VBQ score, DXA T-score, and QCT derived vBMD. METHODS: The osteoporotic classifications recommended by the World Health Organization and American College of Radiology were used to categorize the DXA T-score and QCT-derived BMD, respectively. For each patient, the VBQ score was calculated using T1-weighted MR images. Correlation analysis between VBQ and DXA/QCT was performed. Receiver operating characteristic (ROC) curve analysis, including determination of the area under the curve (AUC), was performed to assess the predictive performance of VBQ for osteoporosis. RESULTS: A total of 452 patients (98 men aged >60 years and 354 postmenopausal women) were included in the analysis. Across different BMD categories, the correlation coefficients between the VBQ score and BMD ranged from -0.211 to -0.511, and the VBQ1.5T score and QCT BMD demonstrated the strongest correlation. The VBQ score was a significant classifier of osteoporosis detected by either DXA or QCT, with VBQ1.5T showing the highest discriminative power for QCT-osteoporosis (AUC=0.744, 95% CI=0.685-0.803). In ROC analysis, the VBQ1.5T threshold values ranged from 3.705 to 3.835 with a sensitivity between 48% and 55.6% and a specificity between 70.8% and 74.8%, while the VBQ3.0T threshold values ranged from 2.59 to 2.605 with a sensitivity between 57.6% and 67.1% and a specificity between 67.8% and 69.7%. CONCLUSIONS: VBQ1.5T exhibited better discriminability between patients with and without osteoporosis than VBQ3.0T. Considering the non-negligible difference in osteoporosis diagnosis threshold values between the VBQ1.5T and VBQ3.0T scores, it is essential to clearly distinguish the magnetic field strength when assessing the VBQ score.


Assuntos
Osteoporose , Fraturas por Osteoporose , Masculino , Humanos , Feminino , Idoso , Densidade Óssea , Estudos de Casos e Controles , Estudos Prospectivos , Osteoporose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/cirurgia , Absorciometria de Fóton/métodos , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/cirurgia , Vértebras Lombares
3.
BMC Geriatr ; 23(1): 231, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069511

RESUMO

BACKGROUND: Robust evidence on whether diagnostic discordance exists between lumbar osteoporosis detected by quantitative computed tomography (QCT) vs. dual-energy X-ray absorptiometry (DXA) is still lacking. In this study involving a relatively large prospective cohort of older men (aged > 60 years) and postmenopausal women, we assessed lumbar QCT-derived volumetric bone mineral density (vBMD) and DXA-derived area BMD and evaluated their predictive performance for prevalent vertebral fracture (VF). METHODS: A total of 501 patients who underwent spinal surgery from September 2020 to September 2022 were enrolled. The criteria recommended by the American College of Radiology and the World Health Organization were used for lumbar osteoporosis diagnosis. The osteoporosis detection rates between QCT and DXA were compared. QCT-vBMD was plotted against the DXA T score, and the line of best fit was calculated based on linear regression. Multivariate logistic regression was used to analyze the associations between risk factors and VF. Receiver operating characteristic curve analysis was performed, and the corresponding area under the curve (AUC) was calculated. RESULTS: QCT screening showed that 60.7% of patients had osteoporosis, whereas DXA screening showed that 50.7% of patients had osteoporosis. Diagnoses were concordant for 325 (64.9%) patients. In all, 205 patients suffered a VF of at least one anatomic level. Of these, 84.4% (173/205) were diagnosed with osteoporosis by QCT, while only 73.2% (150/205) were diagnosed by DXA. Multivariate logistic regression showed that osteoporosis detected by QCT exhibited a stronger relationship with VF than that detected by DXA (unadjusted OR, 6.81 vs. 5.04; adjusted OR, 3.44 vs. 2.66). For discrimination between patients with and without VF, QCT-vBMD (AUC = 0.802) showed better performance than DXA T score (AUC = 0.76). CONCLUSION: In older patients undergoing spinal surgery, QCT-vBMD is more helpful than DXA in terms of osteoporosis detection rate and prediction of patients with prevalent VFs.


Assuntos
Osteoporose , Fraturas da Coluna Vertebral , Masculino , Humanos , Feminino , Idoso , Absorciometria de Fóton/métodos , Estudos Prospectivos , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Densidade Óssea , Tomografia Computadorizada por Raios X
4.
Molecules ; 28(4)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36838705

RESUMO

Combretastatin A-4 (CA-4) is a potent tubulin polymerisation inhibitor. However, the clinical application of CA-4 is limited owing to its low aqueous solubility and the easy conversion of the olefin double bond from the more active cis- to the less active trans-configuration. Several structural modifications were investigated to improve the solubility of CA-4 derivatives. Among the compounds we synthesized, the kinetic solubility assay revealed that the solubility of compounds containing a piperazine ring increased the most, and the solubility of compounds 12a1, 12a2, 15 and 18 was increased 230-2494 times compared with that of the control compound (Z)-3-(4-aminophenyl)-2-(3,4,5-trimethoxyphenyl)acrylonitrile (9a). In addition, these synthesised stilbene nitriles had high anticancer cell (AGS, BEL-7402, MCF-7, and HCT-116) selectivity over L-02 and MCF-10A normal cells while maintaining micromolar activity against cancer cells. The most cytotoxic compound is 9a, and the IC50 value is 20 nM against HCT-116 cancer cells. Preliminary studies indicated that compound 12a1 had excellent plasma stability and moderate binding to rat plasma proteins, suggesting it is a promising lead compound for the development of an anticancer agent.


Assuntos
Antineoplásicos , Estilbenos , Antineoplásicos/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Solubilidade , Estilbenos/química , Relação Estrutura-Atividade , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacologia , Humanos , Linhagem Celular Tumoral
5.
Microsyst Nanoeng ; 8: 78, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35818382

RESUMO

The accurate, continuous analysis of healthcare-relevant gases such as nitrogen oxides (NOx) in a humid environment remains elusive for low-cost, stretchable gas sensing devices. This study presents the design and demonstration of a moisture-resistant, stretchable NOx gas sensor based on laser-induced graphene (LIG). Sandwiched between a soft elastomeric substrate and a moisture-resistant semipermeable encapsulant, the LIG sensing and electrode layer is first optimized by tuning laser processing parameters such as power, image density, and defocus distance. The gas sensor, using a needlelike LIG prepared with optimal laser processing parameters, exhibits a large response of 4.18‰ ppm-1 to NO and 6.66‰ ppm-1 to NO2, an ultralow detection limit of 8.3 ppb to NO and 4.0 ppb to NO2, fast response/recovery, and excellent selectivity. The design of a stretchable serpentine structure in the LIG electrode and strain isolation from the stiff island allows the gas sensor to be stretched by 30%. Combined with a moisture-resistant property against a relative humidity of 90%, the reported gas sensor has further been demonstrated to monitor the personal local environment during different times of the day and analyze human breath samples to classify patients with respiratory diseases from healthy volunteers. Moisture-resistant, stretchable NOx gas sensors can expand the capability of wearable devices to detect biomarkers from humans and exposed environments for early disease diagnostics.

6.
ACS Appl Mater Interfaces ; 14(15): 17818-17825, 2022 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-35394746

RESUMO

The surge in air pollution and respiratory diseases across the globe has spurred significant interest in the development of flexible gas sensors prepared by low-cost and scalable fabrication methods. However, the limited breathability in the commonly used substrate materials reduces the exchange of air and moisture to result in irritation and a low level of comfort. This study presents the design and demonstration of a breathable, flexible, and highly sensitive NO2 gas sensor based on the silver (Ag)-decorated laser-induced graphene (LIG) foam. The scalable laser direct writing transforms the self-assembled block copolymer and resin mixture with different mass ratios into highly porous LIG with varying pore sizes. Decoration of Ag nanoparticles on the porous LIG further increases the specific surface area and conductivity to result in a highly sensitive and selective composite to detect nitrogen oxides. The as-fabricated Ag/LIG gas sensor on a flexible polyethylene substrate exhibits a large response of -12‰, a fast response/recovery of 40/291 s, and a low detection limit of a few parts per billion at room temperature. Integrating the Ag/LIG composite on diverse fabric substrates further results in breathable gas sensors and intelligent clothing, which allows permeation of air and moisture to provide long-term practical use with an improved level of comfort.

7.
Braz. J. Pharm. Sci. (Online) ; 58: e201026, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420474

RESUMO

Abstract Serum uric acid (UA) is a traditional biomarker in the clinical diagnosis of gout and hyperuricemia. However, serum treatment and storage are cumbersome, and wounds are susceptible to infection. Therefore, in this study, a simple and noninvasive method was developed to detect the UA in human saliva to monitor the gout. An Inertsil ODS-3 column was used for the analysis under the condition of isocratic elution with the mixed solution phosphate buffer (74 mM, pH=2.2): Methanol=98:2 (v:v) and the UV detection at 284 nm. Using salivary UA data from healthy volunteers (HVs) (n=68) and gout patients (GPs) (n=14), we examined the salivary UA difference in their content. The intra-and inter-day accuracy and precision (RSD %) were less than 2.56%, the limit of detection (LOD) of UA was 5.0 ng/mL, the mean recoveries of the corresponding compounds were 102.48%. Saliva levels of UA in HVs and GPs were 35.26±14.06 µg/mL and 91.96±23.90 µg/mL, respectively. The concentrations of salivary UA in GPs were significantly higher than those in HVs ( p < 0.001). This method was also expected to monitor the hyperuricemia and other metabolic disorders in the future


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Saliva , Ácido Úrico/análise , Estudo de Validação , Voluntários Saudáveis/classificação , Gota/patologia , Pacientes/classificação , Cromatografia Líquida de Alta Pressão/métodos
8.
Br J Pharmacol ; 177(12): 2793-2811, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32022249

RESUMO

BACKGROUND AND PURPOSE: Regulating macrophage-hepatocyte crosstalk through P2X7 receptors has led to new pharmacological strategies to reverse alcoholic hepatosteatosis. We investigated how tetrahydroxystilbene glucoside (2354glu), isolated from Polygonum multiflorum, modulates macrophage-hepatocyte crosstalk during alcoholic hepatosteatosis. EXPERIMENTAL APPROACH: A model of alcoholic hepatosteatosis was established by giving ethanol intragastrically to C57BL/6 mice. HepG2 cells were incubated in conditioned medium from LPS+ATP-activated THP-1 human macrophages with silenced or overexpressed P2X7 receptors. THP-1 macrophages or mouse peritoneal macrophages were pretreated with 2354glu for 1 hr prior to LPS+ATP stimulation. Western blots, RT-PCR and immunohistochemical analysis were used, along with over-expression and silencing of P2X7 receptors. KEY RESULTS: Knockdown or overexpression of P2X7 receptors in THP-1 macrophages affected release of mature IL-1ß and, subsequently, modulated lipid metabolism in HepG2 cells via the LKB-AMPK pathway. 2354glu ameliorated alcoholic hepatosteatosis in mice by regulating LKB1-AMPK-SREBP1 pathway and its target genes. Suppression of P2X7 receptor activation by 2354glu inhibited IL-1ß release and reduced macrophage and neutrophil infiltration. In macrophages stimulated with LPS+ATP, expression of P2X7 receptors, caspase-1 and NF-κB, release of IL-1ß, calcium influx and PI uptake were reduced by 2354glu. SIRT1-LKB1-AMPK-SREBP1 axis-mediated lipid accumulation in HepG2 cells was reduced when they were cultured with conditioned media from LPS+ATP-activated THP-1 macrophages pretreated with 2354glu. CONCLUSION AND IMPLICATIONS: Modulation of P2X7 receptors in macrophages regulated lipid accumulation in hepatocytes during alcoholic hepatosteatosis. 2354glu might be a promising candidate that targets P2X7 receptors in macrophages interacting with hepatocytes during alcoholic hepatosteatosis.


Assuntos
Macrófagos , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina , Animais , Glucosídeos , Hepatócitos/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estilbenos
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