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1.
J Hazard Mater ; 467: 133654, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38341894

RESUMEN

Self-propelled micro/nanomotors have attracted great attention for environmental remediation, however, their use for radioactive waste detection and removal has not been addressed. Engineered micromotors that are able to combine fast detection and highly adsorptive capability are promising tools for radioactive waste management but remain challenging. Herein, we design self-propelled micromotors based on zeolite imidazolate framework (ZIF-8)-hydrogel composites via inverse emulsion polymerization and show their potential for efficient uranium detection and removal. The incorporation of magnetic ferroferric oxide nanoparticles enables the magnetic recycling and actuation of the single micromotors as well as formation of swarms of worm-like or tank-treading structure. Benefited from the enhanced motion, the micromotors show fast and high-capacity uranium adsorption (747.3 mg g-1), as well as fast uranium detection based on fluorescence quenching. DFT calculation confirms the strong binding between carboxyl groups and uranyl ions. The combination of poly(acrylic acid-co-acrylamide) with ZIF-8 greatly enhances the fluorescence of the micromotor, facilitating the high-resolution fluorescence detection. A low detection limit of 250 ppb is reached by the micromotors. Such self-propelled micromotors provide a new strategy for the design of smart materials in remediation of radioactive wastewater.

2.
Small ; : e2308318, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38258396

RESUMEN

In nature, many organisms are capable of self-organizing into collective groups through local communications to perform complex tasks that individuals cannot complete. To date, the reported artificial microswarms either rely on toxic chemical reactions for communication or lack the hierarchical controllability and functionality, which is unfavorable for practical applications. To this end, this exploits the ion-exchange reaction enabled hierarchical swarm composed of cationic ion exchange resin and magnetic microspheres of internal information exchange. The swarm is reconfigurable under magnetic fields, generating ordered structures of controllable mobilities and even reversed hierarchy, able to navigate in confined and complex environments. Moreover, the swarm shows interesting communications among each other, such as merging, splitting, and member exchange, forming multi-leader groups, living crystals, and complex vortices. Furthermore, the swarm functions as a dual-functional microreactor, which can load, transport, and release drugs in a pH-enhanced manner, as well as effectively degrade antibiotics via light-enhanced Fenton-like reaction in polluted water. The organized structure of the swarm greatly improves the drug loading/transport efficiency and the local concentration of catalysts for fast pollutant removal. This design lays the foundation for the design of dual-functional micro/nanorobots for intelligent drug delivery and advanced environmental remediation.

3.
Nanomaterials (Basel) ; 13(21)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37947744

RESUMEN

Swarms of self-propelled micromotors can mimic the processes of natural systems and construct artificial intelligent materials to perform complex collective behaviors. Compared to self-propelled Janus micromotors, the isotropic colloid motors, also called micromotors or microswimmers, have advantages in self-assembly to form micromotor swarms, which are efficient in resistance to external disturbance and the delivery of large quantity of cargos. In this minireview, we summarize the fundamental principles and interactions for the assembly of isotropic active particles to generate micromotor swarms. Recent discoveries based on either catalytic or external physical field-stimulated micromotor swarms are also presented. Then, the strategy for the reconstruction and motion control of micromotor swarms in complex environments, including narrow channels, maze, raised obstacles, and high steps/low gaps, is summarized. Finally, we outline the future directions of micromotor swarms and the remaining challenges and opportunities.

4.
Front Med (Lausanne) ; 10: 1163371, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034526

RESUMEN

Purpose: This study aimed to evaluate the efficacy and safety of same-session flexible ureteroscopy (fURS) for the treatment of bilateral upper urinary tract stones and to examine the influence of stone load on the outcome of same-session fURS, stratifying by total diameter of stones (TDS) ≤30 mm vs. >30 mm. Patients and methods: We retrospectively reviewed all cases of same-session fURS performed for bilateral upper urinary tract stones at four institutions between January 2017 and September 2020. All patients were divided into two groups based on TDS, ≤30 mm and >30 mm. Data on patient demographics, stone characteristics, surgical results, and complications were collected and analyzed for differences between the two groups. Stone-free rate (SFR) was defined as patients endoscopically stone-free or with radiological fragments <2 mm of each renal unit. Results: A total of 121 patients with bilateral upper urinary tract stones underwent same-session fURS, consisting of 73 patients in the TDS ≤ 30 mm group and 48 patients in the TDS > 30 mm group. The mean bilateral stone size was 28.2 ± 12.2 mm (range: 9.1-38.4 mm), with a mean operating time of 97.1 ± 39.6 min (range: 19-220 min). The SFR was 54.5% after the first fURS, and SFR increased to 97.5% after re-fURS for residual stones. The operation time for the TDS > 30 mm group was longer than that of the TDS ≤ 30 mm group (85.1 ± 36.5 vs. 115.4 ± 37.4 min, p < 0.001). The SFR after the first fURS was significantly lower in the TDS > 30 mm group than in the TDS ≤ 30 mm group (25.0% vs. 73.9%, p < 0.001). Although there was no statistically significant difference in overall SFR between the two groups (93.7% vs. 100%, p = 0.060), the rate of re-fURS for residual stones was higher in the TDS > 30 mm group than in the TDS ≤ 30 mm group (75% vs. 26%, p < 0.001). There were no significant differences in length of hospital stay (LOS) (2.2 ± 0.7 vs. 2.3 ± 1.0, p = 0.329) or complication rate (10.9% vs. 14.6%, p = 0.582) between the two groups. Conclusion: The results suggested that same-session fURS can be effectively performed with a low complication rate. A higher SFR after the first fURS can be achieved in the case of bilateral upper urinary tract stones with TDS ≤ 30 mm, and priority should be given to same-session fURS.

5.
Medicine (Baltimore) ; 102(17): e33648, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37115052

RESUMEN

In patients with stage IA non-small cell lung cancer (NSCLC), uniportal video-assisted thoracic surgery (U-VATS) anatomical segmentectomy removes the lung tumor while preserving lung function as much as possible, and it is therefore an alternative to lobectomy. Patients with stage IA NSCLC receiving U-VATS segmental resection at our institution from September 2017 to June 2019 were compared with patients receiving U-VATS lobectomy. A total of 47 patients received segmentectomy and 209 patients received U-VATS lobectomy in the same period. Propensity score matching was conducted to diminish bias. The final study cohort included 42 patients who received segmentectomy and 42 propensity score matching-matched patients who received lobectomy. Perioperative parameters and postoperative complications, length of hospital stay, postoperative forced expiratory volume in 1 s (FEV1), and forced vital capacity (FVC) were compared between the 2 groups. Surgery was successfully completed in all patients. The mean follow-up was for 8.2 months. The postoperative complication rate was comparable between the 2 groups: 31.0% in segmentectomy patients versus 35.7% in lobectomy patients (P = .643). At 1 month after surgery, FEV1% and FVC% were not significantly different between the 2 groups (P > .05). At 3 months after surgery, FEV1 and FVC were higher in segmentectomy patients than in lobectomy patients (FEV1, 82.79% ± 6.36% vs 78.55% ± 5.42%; FVC, 81.66% ± 6.09% vs 78.90% ± 5.58%, P < .05). Patients receiving segmentectomy suffer less pain and have better postoperative lung function and higher quality of life.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Anciano , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Calidad de Vida , Neumonectomía/efectos adversos , Pulmón/patología , Complicaciones Posoperatorias/etiología , Cirugía Torácica Asistida por Video/efectos adversos
6.
Environ Sci Pollut Res Int ; 30(11): 32065-32082, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36462073

RESUMEN

With the recent increase in global focus on green energy, the application of thermal infrared remote sensing data for the detection of geothermal anomalies has attracted wide attention as it can overcome the difficulty of using only ground surveying. This study aimed to highlight areas of geothermal anomalies with land surface temperature (LST) time series data in winter derived from thermal infrared remote sensing. To extract LST anomaly areas in the Ruili Basin for geothermal prospecting, nine types of data on the study area in winter during 2014 ~ 2021 from Landsat 8 were analyzed. Landsat 8 LST inversion data based on the mono-window algorithm (MWA) can be used to identify hot springs, volcanoes, and other heat-related phenomena. Superimposing LST anomalies for each cycle through drilling data, excluding the heat island effect, geothermal anomaly regions could be plotted. The results show that the accuracy of MWA LST varied within 2 K, which is acceptable for geothermal energy and higher than those of the radiative transfer equation (RTE) algorithm and MODIS LST products. Three high-LST regions in the southeast of the study area were identified as geothermal anomaly areas (A, B, and C), and region B was further verified through a comprehensive field investigation of geothermal wells, supplemented by the temperature gradient (TG) method. The findings reveal that the distribution of geothermal anomaly areas and high-LST areas are highly consistent with the northeast trending fault structure; faults act as thermal channels and help in accurately detecting local LST anomalies. Overall, the infrared remote sensing method proved to be a valid technique for detecting LST anomalies. Considering the synergy between thermal infrared surface detection and subsurface exploration methods, the identification of known geothermal fields (B) and other possible areas (A and C) has significance in the upscaling of local geologic information to regional prospecting, thus providing a direction for future geothermal research.


Asunto(s)
Calor , Tecnología de Sensores Remotos , Ciudades , Monitoreo del Ambiente/métodos , Temperatura , China
7.
Environ Pollut ; 308: 119684, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35764183

RESUMEN

Perfluorooctanoic acid (PFOA) is abundant in environment due to its historical uses in consumer products and industrial applications. Exposure to low doses of PFOA has been associated with various disease risks, including neurological disorders. The underlying mechanism, however, remains poorly understood. In this study, we examined the effects of low dose PFOA exposure at 0.4 and 4 µg/L on the morphology, epigenome, mitochondrion, and neuronal markers of dopaminergic (DA)-like SH-SY5Y cells. We observed persistent decreases in H3K4me3, H3K27me3 and 5 mC markers in nucleus along with alterations in nuclear size and chromatin compaction percentage in DA-like neurons differentiated from SH-SY5Y cells exposed to 0.4 and 4 µg/L PFOA. Among the selected epigenetic features, DNA methylation pattern can be used to distinguish between PFOA-exposed and naïve populations, suggesting the involvement of epigenetic regulation. Moreover, DA-like neurons with pre-differentiation PFOA exposure exhibit altered network connectivity, mitochondrial volume, and TH expression, implying impairment in DA neuron functionality. Collectively, our results revealed the prolonged effects of developmental PFOA exposure on the fitness of DA-like neurons and identified epigenome and mitochondrion as potential targets for bearing long-lasting changes contributing to increased risks of neurological diseases later in life.


Asunto(s)
Fluorocarburos , Neuroblastoma , Biomarcadores/metabolismo , Caprilatos/metabolismo , Caprilatos/toxicidad , Metilación de ADN , Dopamina/metabolismo , Epigénesis Genética , Fluorocarburos/metabolismo , Fluorocarburos/toxicidad , Humanos , Mitocondrias/metabolismo , Neuroblastoma/metabolismo , Neuronas/metabolismo
8.
Chem Commun (Camb) ; 58(33): 5144-5147, 2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35383796

RESUMEN

Rh(III)-Catalyzed 1 : 2 coupling of 3-aryl-2H-benzo[b][1,4]oxazines with α-diazo-ß-ketoesters has been realized for the mild synthesis of spiropyrans. The reaction proceeded via twofold C-H activation followed by unusual [3+3] and [4+2] annulation with decent functional group tolerance. Moreover, a pyranoid-skeleton intermediate was isolated as a key intermediate as a result of monoalkylation and enol oxygen annulation, which offers direct mechanistic insight.


Asunto(s)
Rodio , Catálisis , Oxazinas
9.
Front Pharmacol ; 12: 710169, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34552485

RESUMEN

Rheumatoid arthritis (RA) is closely associated with periarticular osteopenia and leads to a high risk of generalized osteoporosis. Although glucocorticoid (GC) treatment ameliorates joint degradation and manages inflammation in RA, GC application may induce further bone quality deterioration in RA patients. Current treatments for RA lack relevant strategies for the prevention and treatment of osteopenia in RA. In this study, we aimed to investigate whether salvianolate treatment ameliorated osteopenia in prednisone-treated RA rats. Lewis rats with collagen-induced arthritis (CIA) were administered prednisone (PDN) or PDN plus salvianolate (PDN+Sal) treatment for 90 days. The effects of Sal were investigated in PDN-treated CIA rats. To further evaluate the effects of Sal under inflammatory conditions, we investigated the effects of Sal treatment on the TNF-α-induced inflammatory response in MC3T3-E1 osteoblasts. Bone histomorphometry, bone mineral density (BMD), bone biomechanical properties, micro-computed tomography (micro-CT), immunohistochemistry, RT-PCR and western blot analyses were performed to evaluate the effects of Sal. The results demonstrated that RA induced bone loss and bone quality deterioration, with high bone turnover in CIA rats. PDN+Sal treatment significantly increased BMD and trabecular/cortical bone mass, suppressed inflammation, and improved bone biomechanical properties compared to CIA control and PDN treatment. PDN+Sal treatment significantly suppressed bone resorption and the RANKL and RANKL/OPG ratios compared to PDN. PDN+Sal and PDN treatment significantly inhibited TNF-α by 82 and 83%, respectively, and both suppressed inflammation in CIA rats. However, there was no significant difference between PDN+Sal and PDN treatment alone in regard to bone formation parameters or the management of inflammation and arthropathy. Sal significantly increased Osterix, OPN, and Col1a1 while decreasing RANKL, TRAF6, and TRAIL gene in TNF-α-induced MC3T3-E1 osteoblasts. Sal significantly increased Osterix, OPN and RUNX2 while decreasing NF-κB, TRAF6 and IL-1ß protein in TNF-α-induced MC3T3-E1 osteoblasts. The results suggested that salvianolate treatment ameliorated osteopenia and improved bone quality in prednisone-treated RA rats, and the potential mechanism may be related to the regulation of the RANKL/RANK/OPG signaling pathway, TRAIL-TRAF6-NFκB signal axis, and downregulation of inflammatory cytokines. Salvianolate could be used as a promising supplemental therapeutic strategy to ameliorate osteopenia and improve bone quality in GC-treated RA patients.

10.
Sensors (Basel) ; 21(15)2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34372418

RESUMEN

Research on fusion modeling of high spatial and temporal resolution images typically uses MODIS products at 500 m and 250 m resolution with Landsat images at 30 m, but the effect on results of the date of reference images and the 'mixed pixels' nature of moderate-resolution imaging spectroradiometer (MODIS) images are not often considered. In this study, we evaluated those effects using the flexible spatiotemporal data fusion model (FSDAF) to generate fusion images with both high spatial resolution and frequent coverage over three cotton field plots in the San Joaquin Valley of California, USA. Landsat images of different dates (day-of-year (DOY) 174, 206, and 254, representing early, middle, and end stages of the growing season, respectively) were used as reference images in fusion with two MODIS products (MOD09GA and MOD13Q1) to produce new time-series fusion images with improved temporal sampling over that provided by Landsat alone. The impact on the accuracy of yield estimation of the different Landsat reference dates, as well as the degree of mixing of the two MODIS products, were evaluated. A mixed degree index (MDI) was constructed to evaluate the accuracy and time-series fusion results of the different cotton plots, after which the different yield estimation models were compared. The results show the following: (1) there is a strong correlation (above 0.6) between cotton yield and both the Normalized Difference Vegetation Index (NDVI) from Landsat (NDVIL30) and NDVI from the fusion of Landsat with MOD13Q1 (NDVIF250). (2) Use of a mid-season Landsat image as reference for the fusion of MODIS imagery provides a better yield estimation, 14.73% and 17.26% higher than reference images from early or late in the season, respectively. (3) The accuracy of the yield estimation model of the three plots is different and relates to the MDI of the plots and the types of surrounding crops. These results can be used as a reference for data fusion for vegetation monitoring using remote sensing at the field scale.


Asunto(s)
Productos Agrícolas , Imágenes Satelitales , Gossypium , Estaciones del Año
11.
Sensors (Basel) ; 20(14)2020 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-32707649

RESUMEN

The objective of this study was to develop a low-cost method for rice growth information obtained quickly using digital images taken with smartphone. A new canopy parameter, namely, the canopy volume parameter (CVP), was proposed and developed for rice using the leaf area index (LAI) and plant height (PH). Among these parameters, the CVP was selected as an optimal parameter to characterize rice yields during the growth period. Rice canopy images were acquired with a smartphone. Image feature parameters were extracted, including the canopy cover (CC) and numerous vegetation indices (VIs), before and after image segmentation. A rice CVP prediction model in which the CC and VIs served as independent variables was established using a random forest (RF) regression algorithm. The results revealed the following. The CVP was better than the LAI and PH for predicting the final yield. And a CVP prediction model constructed according to a local modelling method for distinguishing different types of rice varieties was the most accurate (coefficient of determination (R2) = 0.92; root mean square error (RMSE) = 0.44). These findings indicate that digital images can be used to track the growth of crops over time and provide technical support for estimating rice yields.


Asunto(s)
Oryza/crecimiento & desarrollo , Fotograbar , Teléfono Inteligente , Algoritmos , Productos Agrícolas/crecimiento & desarrollo , Hojas de la Planta
12.
J Gene Med ; 22(6): e3174, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32056303

RESUMEN

BACKGROUND: MicroRNAs (miRs) hold critical implications in the modulation of osteogenesis. This work was designed to unravel the underlying regulatory mechanism of miR-22 during osteoblast differentiation. METHODS: Synthetic miR-22 mimics or inhibitors were transfected into preosteoblast MC3T3-E1 cells to regulate miR-22 expression. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and flow cytometry analyses were employed to assess cell proliferation and apoptosis. A quantitative real-time polymerase chain reaction and western blot assays were applied to measure mRNA and protein expression. Alkaline phosphatase activity and alizarin red staining were tested to further analyze cell differentiation. In silico analysis and luciferase reporter assays were utilized to identify the direct binding between miR-22 and its potential target. RESULTS: MTT and flow cytometry analyses showed that miR-22 repressed MC3T3-E1 cell viability and promoted cell apoptosis. By detecting osteogenic-specific molecule expression, alkaline phosphatase activity and alizarin red staining, miR-22 was observed to suppress osteogenic differentiation of MC3T3-E1 cells. In silico analysis and luciferase reporter assays confirmed that ESR1 is a direct target gene of miR-22. In addition, miR-22 expression affected the phosphorylation of p38 mitogen-activated protein kinase and Jun N-terminal kinase expression in MC3T3-E1 cells. CONCLUSIONS: The findings of the present study highlight the functional significance of miR-22 in osteoblast differentiation and suggest its role as a possible therapeutic target in metabolic bone disorders.


Asunto(s)
Receptor alfa de Estrógeno/genética , Regulación de la Expresión Génica , Sistema de Señalización de MAP Quinasas , MicroARNs/genética , Osteoblastos/metabolismo , Interferencia de ARN , Animales , Apoptosis/genética , Biomarcadores , Diferenciación Celular/genética , Línea Celular , Supervivencia Celular/genética , Ratones , Osteoblastos/citología , Osteogénesis/genética , ARN Mensajero/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
PLoS One ; 13(9): e0202885, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30212470

RESUMEN

Osteoporosis (OP) is a systemic skeletal disorder, manifesting with a reduction in bone mass and deterioration of the microarchitecture. Mesenchymal stem cells (MSCs) have an innate ability to differentiate into several cell types, including osteoblasts (OB). Ginsenoside Rb1 (GRb1) is an ethanol extract from ginseng and contains a highly concentrated form of ginsenoside. GRb1 shows extensive beneficial health effects such as anti-oxidative and anti-inflammatory functions, modulating the immune system and inhibiting osteoclastogenesis. We hypothesized that GRb1 can promote MSC differentiation into OBs and inhibit bone loss. In the present study, we aimed to address two questions: (1) Will GRb1 have a positive effect on osteogenic differentiation of MSCs? and (2) Will GRb1 halt bone loss in ovariectomized (OVX) rats? We investigated the effects of GRb1 on viability and osteogenic differentiation of rat mesenchymal stem cells (rMSCs). Our results showed that GRb1 at concentrations of 10-8 M and 10-6 M can increase alkaline phosphatase activity, mineralization and the expression of osteogenic related proteins, such as osteopontin and osteoprotegerin, while incubating rMSCs with osteogenic induction medium and GRb1. Adding GRb1 into the medium can prevent rMSCs from Oxidative damage at the concentration of 25µM H2O2. Furthermore, 40 4-month-old rats were assigned to 5 groups(8 rats per group): the basal group, the sham group, the OVX group, the high dose of GRb1 group (6 mg/kg/day) and the low dose of GRb1 group (3 mg/kg/day). Rats recrived treatment 3days after surgery and last for 14 weeks. Examinations included serum analysis, mechanical testing, Masson-Goldner trichrome staining and bone histomorphometry analysis. The results showed that OVX can lead to dyslipidemia and excessive oxidative stress, whereas GRb1 cannot significantly halt dyslipidemia and excessive oxidative stress in OVX rats. In addition, the bone density of the lumbar vertebra and femur were decreased significantly in the OVX rats, and GRb1 could not inhibit bone loss. Bone histomorphometry analysis showed that the number and width of bone trabecula of the tibia were reduced in OVX rats, and GRb1 could not prevent their occurrence. A bone biomechanics assay showed that GRb1 cannot improve the ability of bone structure to resist fracture of the femur in OVX rats. The current study demonstrated that GRb1 has an obvious effect on osteogenic differentiation in rMSCs but no obvious effect on bone loss in OVX rats. These findings indicate GRb1 has a positive effect on rMSCs but does not have an effect on bone loss in OVX rats at the concentration we used.


Asunto(s)
Conservadores de la Densidad Ósea/farmacología , Ginsenósidos/farmacología , Osteoporosis/tratamiento farmacológico , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Células Madre Mesenquimatosas/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ovariectomía , Ratas Sprague-Dawley , Organismos Libres de Patógenos Específicos , Insuficiencia del Tratamiento
14.
Acta Pharmacol Sin ; 39(4): 633-641, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29323335

RESUMEN

Glucocorticoid (GC)-induced osteoporosis (GIO) is characterized by impaired bone formation, which can be alleviated by tanshinol, an aqueous polyphenol isolated from Salvia miltiorrhiza Bunge. In this study we investigated the molecular mechanisms underlying GC-induced modulation of osteogenesis as well as the possibility of using tanshinol to interfere with GIO. Female SD rats aged 4 months were orally administered distilled water (Con), prednisone (GC, 5 mg·kg-1·d-1), GC plus tanshinol (Tan, 16 mg·kg-1·d-1) or GC plus resveratrol (Res, 5 mg·kg-1·d-1) for 14 weeks. After the rats were sacrificed, samples of bone tissues were collected. The changes in bone formation were assessed using Micro-CT, histomorphometry, and biomechanical assays. Expression of Kruppel-like factor 15 (KLF15), peroxisome proliferator-activated receptor γ 2 (PPARγ 2) and other signaling proteins in skeletal tissue was measured with Western blotting and quantitative RT-PCR. GC treatment markedly increased the expression of KLF15, PPARγ2, C/EBPα and aP2, which were related to adipogenesis, upregulated FoxO3a pathway proteins (FoxO3a and Gadd45a), and suppressed the canonical Wnt signaling (ß-catenin and Axin2), which was required for osteogenesis. Thus, GC significantly decreased bone mass and bone quality. Co-treatment with Tan or Res effectively counteracted GC-impaired bone formation, suppressed GC-induced adipogenesis, and restored abnormal expression of the signaling molecules in GIO rats. We conclude that tanshinol counteracts GC-decreased bone formation by inhibiting marrow adiposity via the KLF15/PPARγ2/FoxO3a/Wnt pathway.


Asunto(s)
Adipogénesis/efectos de los fármacos , Ácidos Cafeicos/uso terapéutico , Osteogénesis/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Vía de Señalización Wnt/efectos de los fármacos , Adipocitos/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Médula Ósea/metabolismo , Proteína alfa Potenciadora de Unión a CCAAT/genética , Regulación hacia Abajo , Proteínas de Unión a Ácidos Grasos/genética , Femenino , Proteína Forkhead Box O3/genética , Factores de Transcripción de Tipo Kruppel/genética , PPAR gamma/genética , Prednisona/administración & dosificación , Prednisona/farmacología , Ratas Sprague-Dawley , Resveratrol , Estilbenos/administración & dosificación , Estilbenos/farmacología , Regulación hacia Arriba , Vía de Señalización Wnt/genética
15.
J Bone Miner Metab ; 36(6): 628-639, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29124434

RESUMEN

Glucocorticoids (GCs) are often prescribed to treat rheumatoid arthritis (RA) in the long term, but there is still controversy in the administration of GCs, mainly because of the adverse reactions such as osteoporosis. Numerous studies have demonstrated that osteoporosis could be induced by GCs in normal rats. However, few experiments have focused on whether osteoporosis could be induced or aggravated by GCs in collagen induced arthritis (CIA) rats. We have investigated bone changes in CIA rats treated with prednisone at 4.5 mg/kg/day for 30 and 90 days by bone histomorphometry, bone mineral density (BMD), micro-CT, biomechanical test, and enzyme-linked immunosorbant assay. We found that high bone turnover osteoporosis was shown in CIA rats. Prednisone treatment for 30 and 90 days improved articular structure and decelerated the degeneration of the femur in CIA rats, but did not improve BMD and bone biomechanics. We conclude that osteoporosis was not aggravated in CIA rats treated with prednisone for 30 and 90 days. On the contrary, prednisone treatment for 30 and 90 days could prevent bone loss of the femur in CIA rats. There was a negative effect on bone metabolism in CIA rats treated with prednisone for 90 days.


Asunto(s)
Artritis Experimental/metabolismo , Fémur/metabolismo , Prednisona/farmacología , Animales , Artritis Experimental/sangre , Artritis Experimental/patología , Artritis Experimental/fisiopatología , Biomarcadores/sangre , Fenómenos Biomecánicos/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Hueso Esponjoso/diagnóstico por imagen , Hueso Esponjoso/efectos de los fármacos , Hueso Esponjoso/patología , Hueso Esponjoso/fisiopatología , Femenino , Fémur/efectos de los fármacos , Fémur/patología , Fémur/fisiopatología , Glucocorticoides/farmacología , Articulaciones/patología , Ratas Endogámicas Lew , Microtomografía por Rayos X
16.
Exp Ther Med ; 14(4): 2779-2788, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28966669

RESUMEN

The aim of the present study was to investigate the effect of salvianolic acid B (Sal B) and danshensu (DSU) on the osteogenic differentiation of bone marrow mesenchymal stem cells (MSCs) and the mechanisms of the effects. The osteogenic differentiation of MSCs in culture was assessed by measuring alkaline phosphatase (ALP) activity, osteocalcin (OCN) production, nitric oxide (NO) production and the mRNA expression levels of osteoprotegerin (OPG) and its ligand by MSCs. MSCs were successfully induced to differentiate into osteoblasts and adipocytes. Sal B and DSU increased the ALP activity and the production of OCN in the absence of an ossification inducer. The increase in ALP activity was more pronounced when induction was combined with the osteogenic inducer, Sal B, which enhanced the expression of OPG; however, Sal B reduced the expression of receptor activator of nuclear factor-κB ligand (RANKL) by MSCs. Sal B reversed the inhibitory effect of N-nitro L-arginine methylester on the MSCs and increased ALP activity, OCN content and the OPG/RANKL ratio. Based on these results, it was concluded that Sal B increases the osteogenic differentiation of MSCs, most likely by regulating the nitric oxide pathway.

17.
Planta Med ; 83(16): 1264-1273, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28427101

RESUMEN

Tanshinol is a major water-soluble active component of Salvia miltiorrhiza. In this study, we aimed to investigate whether tanshinol has potential therapeutic effects against glucocorticoid-induced osteoporosis and glucocorticoid-induced myopathy. Ninety-six female Sprague-Dawley rats were randomly assigned to five groups: a control group, a model group, and three model groups treated with 25 or 50 mg/kg of tanshinol, or calcitriol. All model groups received prednisone acetate for 90 days to induce glucocorticoid-induced osteoporosis. Afterwards, all animals underwent a surgical procedure to induce bone defects at the right proximal tibia. Prednisone treatment was stopped after surgery, but tanshinol or calcitriol treatment was continued to the endpoint. At the experimental endpoint, compared to the model group, 25 mg/kg tanshinol could significantly reverse glucocorticoid-induced loss of bone mineral density by 12.5 %, while enhancing mechanical bone strength, causing a significant 11 % increase in trabecular number, and reducing trabecular separation by 28 %. In addition, tanshinol improved the bone microarchitecture and prevented glucocorticoid-induced bone loss by promoting bone formation and inhibiting bone resorption. Moreover, results of bone defect repair and muscle weight measurements revealed that tanshinol accelerated the bone fracture healing process and attenuated muscle atrophy caused by glucocorticoid. Furthermore, qRT-PCR analysis showed a 1-fold upregulation in mRNA levels of transforming growth factor beta and roughly 6-fold increases in vascular endothelial growth factor mRNA expression in calluses from the tanshinol groups. Tanshinol also preserved muscular ubiquitin mRNA levels from glucocorticoid-induced elevation. These findings demonstrate the potential benefits of tanshinol against glucocorticoid-induced osteoporosis and glucocorticoid-induced myopathy, which warrants further investigation in future studies.


Asunto(s)
Ácidos Cafeicos/uso terapéutico , Enfermedades Musculares/tratamiento farmacológico , Osteoporosis/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Absorciometría de Fotón , Animales , Ácidos Cafeicos/química , Modelos Animales de Enfermedad , Femenino , Glucocorticoides , Estructura Molecular , Enfermedades Musculares/inducido químicamente , Enfermedades Musculares/patología , Osteoporosis/inducido químicamente , Osteoporosis/patología , Fitoterapia , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Salvia miltiorrhiza , Tomografía
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 566-70, 2017 Feb.
Artículo en Chino | MEDLINE | ID: mdl-30291819

RESUMEN

Soil organic matter (SOM) is one of the most important measuring indexes of soil fertility. How to predict SOM spatial distribution precisely has great significance to soil carbon storage estimation and precision agriculture development. Traditional measurement of SOM, although with higher accuracy, consumes a lot of labor resources and costs long-term monitoring period, therefore, it is hard to achieve dynamic monitor of SOM. Spectroscopy technique has been used in SOM and other soil physicochemical parameters quick measurement. However spatial inversion model accuracy of SOM based on remote sensing images is relatively lower than laboratory model accuracy due to the influence of soil moisture, roughness and so on. In recent years, most studies have not eliminated the effect of moisture. Since moisture has great influence on SOM spectra reflectance, this study introduced the temporal information combined with the spectral information in order to solve this problem. Soil moisture has differences in multi period remote sensing images, and the spectra reflectance is also different. Based on the combination of reflectance from of two periods remote sensing images, the spectral index was constructed to predict SOM in this study. MODIS images of study area acquired in this study area (Blacksoil zone) because of the advantage of high temporal resolution. Spectra reflectance of MODIS images were used to analyze the effect of moisture on soil spectral reflectance, and then the spectral prediction models of SOM were built based on the comprehensive impacts of SOM and soil moisture. The results shows that: (1) the accuracy of SOM prediction model based on single image was lower without consideration of moisture effect, The Root mean square error (RMSE) of SOM prediction model were 0.591, 0.522, 0.545, 0.553, and the determination coefficient (R(2)) were 0.505, 0.614, 0.562, 0.568, 0.645 respectively based on the day of year (DOY) 117, 119, 130, 140, 143 single image. (2) Model with multi temporal images (DOY119 and 143) which considered the effect of moisture and SOM showed better predictive ability. RMSE was 0.442 while R2 was 0.723. Therefore the accuracy and stability of the model were significantly improved, and it can be used to predict the spatial distribution of SOM in regional scale. This study provides important information for regional soil fertility evaluation, soil carbon storage estimation, and precision agriculture development.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2585-9, 2016 Aug.
Artículo en Chino | MEDLINE | ID: mdl-30074369

RESUMEN

Pixel-based processing method mainly extracts spectral information from hyperspectral remote sensing images, but site specific management zone (SSMZ) delineation and crop yield estimation with images need to take spatiotemporal heterogeneity into account. As the spatial resolution of remote sensing data increases, the so-called "salt-and-pepper" problem of pixel-based classification becomes more serious. The spatiotemporal heterogeneity of soil properties and crop biophysical parameters are mainly delineated with grid sampling and geostatistics interpolation, but the widely used method has some problems: time consuming and high cost. Satellite imageries are introduced to delineate SSMZ, but there are also problems needed to be resolved: (1) single date imagery is used to map SSMZ which is difficult to determine the optimal date for SSMZ delineation; (2) only few SSMZs were mapped, which limited application of site specific fertilizing and management; (3) pixel-based method for SSMZ delineation didn't concern the spatial relationship between pixels and site specific management does not implement at pixel level, but at SSMZ level. To improve the accuracy of crop yield estimation, a time-series of hyperspectral airborne images with high spatial resolution (1 m) of a cotton field, which is located in San Joaquin Valley, California US, were acquired and classified by using object-oriented segmentation, then yield predicting models were built, and the accuracy and stability of yield models were validated with determining coefficients R2 and the root mean square error (RMSE). Results are as follows: (1) object-oriented SSMZ delineating method combines spectral, spatial and temporal information, reduces noises in images and yield data, improves the accuracy of yield prediction; (2) for same SSMZ number, first derivative predicting model is more accurate; (3) for same spectral input, models with fewer SSMZs show higher accuracy, which is due to spatial errors of airborne images and yield data. The results will improve monitoring methods for crop growth and yield while accelerate the application of UAV remote sensing in precision agriculture.

20.
J Bone Miner Metab ; 34(5): 500-16, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26210858

RESUMEN

Numerous studies have demonstrated that rheumatoid arthritis (RA) is often associated with bone loss; however, few experiments have focused on cancellous and cortical bone changes in rats during the process of arthritis. We have investigated bone changes in rats with collagen-induced arthritis (CIA) and have explored the characteristics of how RA induces osteoporosis by means of bone histomorphometry, bone biomechanics studies, bone mineral density studies, micro computer tomography, enzyme-linked immunosorbant assay, immunohistochemistry, and Western blot analysis. Bone mineral density of the femur and lumbar vertebrae and biomechanical properties of the femur were decreased in CIA rats. Trabecular bone volume of the tibia and lumbar vertebrae was decreased whereas bone resorption was increased in CIA rats. Bone formation of the tibial shaft in periosteal surfaces was decreased in CIA rats. Furthermore, the trabecular bone loss in CIA rats was severer at 16 weeks than at 8 weeks, as was cortical bone loss. The serum level of tumor necrosis factor α in CIA rats was increased, and the expression of dickkopf 1 and that of receptor activator of nuclear factor κB (RANKL) ligand (RANKL) in the ankle joints were also increased, but the expression of osteoprotegerin (OPG) was decreased. We conclude that CIA rats developed systemic osteoporosis, and that osteoporosis became more serious with CIA development. The mechanism may be related to the increase of bone resorption in cancellous bone cause by upregulation of the expression of DKK-1 and regulation of the RANKL/RANK/OPG signaling pathway, and the decrease of bone formation in cortical bone caused by an increase in the expression of DKK-1.


Asunto(s)
Artritis Experimental/complicaciones , Osteoporosis/etiología , Animales , Articulación del Tobillo/patología , Artritis Experimental/metabolismo , Artritis Experimental/patología , Fenómenos Biomecánicos , Densidad Ósea , Hueso Esponjoso/patología , Femenino , Fémur/fisiopatología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Osteoporosis/metabolismo , Osteoporosis/patología , Osteoporosis/fisiopatología , Osteoprotegerina/metabolismo , Ligando RANK/metabolismo , Ratas , Ratas Endogámicas Lew
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