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This study aimed to investigate clinical effectiveness of stone disintegration by using isolation coupling pad ("icPad") as coupling medium to reduce trapped air pockets during extracorporeal shock wave lithotripsy (ESWL). Patients underwent ESWL between Oct. 2017 and May 2018 were enrolled in this clinical observational study. An electromagnetic lithotripter (Dornier MedTech Europe GmbH Co., Germany) was used in this study. Patients were divided into icPad group P1, P2 and semi-gel group C by different coupling medium. The energy level and total number of shock wave (SW) for group P1 and C was set at level 2 and 3000 and group P2 at level 3 and 2500. The successful stone disintegration rate (SSDR) was determined to evaluate the treatment outcome. All patients were evaluated by KUB film and ultrasonography after 90 days. Complications during ESWL were recorded. A total of 300 patients satisfied the inclusion criteria. There were no significant differences in characteristics of patients and stone among three groups. The corresponding SSDRs for patients in group P1, P2 and C was 73.0%, 73.2% and 55.3%, respectively. The SSDR in group P1 was statistically higher than Group C. Comparing to semi-liquid gel, coupling medium using by icPad could achieve better treatment outcome of stone disintegration in ESWL.
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Cálculos Renais , Litotripsia , Cálculos Ureterais , Fadiga , Humanos , Cálculos Renais/terapia , Resultado do Tratamento , Cálculos Ureterais/terapiaRESUMO
INTRODUCTION: Air pockets between the lithotripter head and body surface are almost inevitably generated when applying a handful of gel onto the contact portion of the treatment head and that on the patient's skin during coupling procedure. These air pockets can compromise the transmission of acoustic energy of shock wave and may significantly affect efficacy of stone disintegration. Comparing to conventional gel, this study aims to investigate efficacy of stone disintegration by using a proprietary isolation-coupling pad ("icPad") as the coupling medium to reduce trapped air pockets during ESWL procedure. METHOD: In this phantom study, Dornier lithotripter (Delta-2 RC, Dornier MedTech Europe GmbH Co., Germany) was used with a proprietary gel pads (icPad, Diameter = 150 mm, Thickness = 4 mm and 8 mm). The lithotripter was equipped with inline camera to observe the trapped air pockets between the contact surface of the lithotripter head. A testing and measuring device were used to observe experimental stone disintegration using icPad and semi-liquid gel. The conventional semi-liquid gel was used as control for result comparison. RESULTS: The stone disintegration rate of icPad 4 mm and 8 mm after 200 shocks of energy at level 2 were significantly higher than that of the semi-liquid gel (disintegration rate 92.3%, 85.0% vs. 45.5%, respectively, p < 0.001). The number of shocks for complete stone disintegration by icPad of 4 mm and 8 mm at the same energy level 2 were significantly lower than that of the semi-liquid gel (the number of shocks 242.0 ± 13.8, 248.7 ± 6.3 vs. 351.0 ± 54.6, respectively, p = 0.011). Furthermore, quantitative comparison of observed air pockets under Optical Coupling Control (OCC) system showed that the area of air pockets in semi-liquid group was significantly larger than that of the group using icPad (8 mm) and that of the group using icPad (8 mm) after sliding (332.7 ± 91.2 vs. 50.3 ± 31.9, 120.3 ± 21.5, respectively, p < 0.05). CONCLUSION: The advantages of icPad includes: (1) reduced the numbers of shock wave and increased stone disintegration rate due to icPad's superior efficacy; (2) significantly reduce trapped air pockets in ESWL coupling. Due to the study limitation, more data are needed to confirm our observations before human trials.
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Géis , Litotripsia/métodos , Ar , Humanos , Litotripsia/instrumentação , Imagens de FantasmasRESUMO
Ectoine has fostered the development of products for skin care and cosmetics. In this study, we employed the marine bacterial strain Marinococcus sp. MAR2 to increase ectoine production by optimizing medium constituents using Response Surface Methodology (RSM) and a fed-batch strategy. The results from the steepest ascent and central composite design indicated that 54 g/L of yeast extract, 14.0 g/L of ammonium acetate, 74.4 g/L of sodium glutamate, and 6.2 g/L of sodium citrate constituted the optimal medium with maximum ectoine production (3.5 g/L). In addition, we performed fed-batch culture in the bioreactor, combining pH and dissolved oxygen to produce ectoine by Marinococcus sp. MAR2. The ectoine production, content, and productivity of 5.6 g/L, 10%, and 3.9 g/L/day were further reached by a fed-batch culture. Thus, the ectoine production by Marinococcus sp. MAR2 using RSM and fed-batch strategy shows its potential for industrial production.
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Diamino Aminoácidos/metabolismo , Bacillaceae/metabolismo , Técnicas de Cultura Celular por Lotes/métodos , Microbiologia Industrial/métodos , Acetatos/análise , Acetatos/metabolismo , Bacillaceae/crescimento & desenvolvimento , Técnicas de Cultura Celular por Lotes/instrumentação , Reatores Biológicos , Meios de Cultura/química , Meios de Cultura/metabolismo , Desenho de Equipamento , Fermentação , Microbiologia Industrial/instrumentação , Citrato de Sódio/análise , Citrato de Sódio/metabolismo , Glutamato de Sódio/análise , Glutamato de Sódio/metabolismoRESUMO
Chondral or osteochondral defects are still controversial problems in orthopedics. Here, chondrocytes labeled with magnetic nanoparticles were cultivated on a biphasic, type II collagen-chitosan/poly(lactic-co-glycolic acid) scaffold in an attempt to develop cultures with trackable cells exhibiting growth, differentiation, and regeneration. Rabbit chondrocytes were labeled with magnetic nanoparticles and characterized by scanning electron microscopy (SEM), transmission electron (TEM) microscopy, and gene and protein expression analyses. The experimental results showed that the magnetic nanoparticles did not affect the phenotype of chondrocytes after cell labeling, nor were protein and gene expression affected. The biphasic type II collagen-chitosan/poly(lactic-co-glycolic) acid scaffold was characterized by SEM, and labeled chondrocytes showed a homogeneous distribution throughout the scaffold after cultivation onto the polymer. Cellular phenotype remained unaltered but with increased gene expression of type II collagen and aggrecan, as indicated by cell staining, indicating chondrogenesis. Decreased SRY-related high mobility group-box gene (Sox-9) levels of cultured chondrocytes indicated that differentiation was associated with osteogenesis. These results are encouraging for the development of techniques for trackable cartilage regeneration and osteochondral defect repair which may be applied in vivo and, eventually, in clinical trials.
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Quitosana/química , Condrócitos/citologia , Condrogênese , Colágeno Tipo II/química , Ácido Láctico/química , Nanopartículas de Magnetita/análise , Ácido Poliglicólico/química , Alicerces Teciduais/química , Animais , Células Cultivadas , Condrócitos/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Engenharia TecidualRESUMO
This study explored the effect of deltamethrin, a pesticide, on intracellular free Ca²âº concentration ([Ca²âº]i) in PC3 human prostate cancer cells. Deltamethrin at concentrations between 5 µM and 20 µM evoked [Ca²âº]i rises in a concentration-dependent manner. This Ca²âº signal was inhibited by 22% by removal of extracellular Ca²âº. Nifedipine, econazole, and SKF96365 also inhibited the Ca²âº signal. Treatment with the endoplasmic reticulum Ca²âº pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) in Ca²âº-free medium nearly abolished deltamethrin-induced [Ca²âº]i rises. Treatment with deltamethrin also inhibited most of BHQ-induced [Ca²âº]i rises. Inhibition of phospholipase C (PLC) with U73122 failed to alter deltamethrin-evoked [Ca²âº]i rises. Deltamethrin killed cells at concentrations of 20-100 µM in a concentration-dependent fashion. Chelation of cytosolic Ca²âº with 1,2-bis (2-aminophenoxy) ethane-N, N, N', N'-tetraacetic acid/acetoxymethyl ester (BAPTA/AM) did not prevent deltamethrin's cytotoxicity. Together, in PC3 human prostate cancer cells, deltamethrin induced [Ca²âº]i rises that involved Ca²âº entry through store-operated Ca²âº channels and PLC-independent Ca²âº release from the endoplasmic reticulum. Deltamethrin induced cytotoxicity in a Ca²âº-independent manner.
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Cálcio/metabolismo , Inseticidas/farmacologia , Nitrilas/farmacologia , Neoplasias da Próstata/metabolismo , Piretrinas/farmacologia , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quelantes/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Masculino , Nitrilas/antagonistas & inibidores , Piretrinas/antagonistas & inibidores , Fosfolipases Tipo C/antagonistas & inibidoresRESUMO
The effect of the antidepressant doxepin on cytosolic Ca²âº concentrations ([Ca²âº](i)) and viability in PC3 human prostate cancer cells was explored. The Ca²âº-sensitive fluorescent dye fura-2 was applied to measure [Ca²âº](i). Doxepin at concentrations of 500-1000 µM induced a [Ca²âº](i) rise in a concentration-dependent manner. The response was reduced partly by removing Ca²âº. Doxepin-evoked Ca²âº entry was suppressed by Ca²âº entry blockers (nifedipine, econazole, SK&F96365), and protein kinase C (PKC) modulators. In the absence of extracellular Ca²âº, incubation with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin or 2,5-di-tert-butylhydroquinone (BHQ) partly inhibit doxepin-induced [Ca²âº](i) rise. Incubation with doxepin nearly inhibited thapsigargin or BHQ-induced [Ca²âº](i) rise. Inhibition of phospholipase C (PLC) with U73122 failed to alter doxepin-induced [Ca²âº](i) rise. At concentrations of 200-250 µM, doxepin killed cells in a concentration-dependent manner. This cytotoxic effect was not reversed by chelating cytosolic Ca²âº with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'- tetraacetic acid/acetoxy methyl (BAPTA/AM). Annexin V/PI staining data implied that doxepin (200 and 250 µM) did not induce apoptosis. Collectively, in PC3 cells, doxepin induced a [Ca²âº](i) rise by evoking PLC-independent Ca²âº release from stores including the endoplasmic reticulum and Ca²âº entry via PKC-sensitive store-operated Ca²âº channels. Doxepin caused cell death that was independent of [Ca²âº](i) rises.
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Antidepressivos/farmacologia , Cálcio/metabolismo , Doxepina/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Humanos , Masculino , Fosfolipases Tipo C/fisiologiaRESUMO
The effect of sertraline, a selective serotonin reuptake inhibitor (SSRI), on cytosolic free Ca²âº concentrations ([Ca²âº](i)) in a rabbit corneal epithelial cell line (SIRC) is unclear. This study explored whether sertraline changed basal [Ca²âº](i) levels in suspended SIRC cells by using fura-2 as a Ca²âº-sensitive fluorescent dye. Sertraline at concentrations between 10-100 µM increased [Ca²âº](i) in a concentration-dependent manner. The Ca²âº signal was reduced by 23% by removing extracellular Ca²âº. Sertraline induced Mn²âº influx, leading to quench of fura-2 fluorescence, suggesting Ca²âº influx. This Ca²âº influx was inhibited by phospholipase A2 inhibitor aristolochic acid, but not by store-operated Ca²âº channel blockers and protein kinase C/A modulators. In Ca²âº-free medium, pretreatment with the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin, cyclopiazonic acid or 2,5-di-tert-butylhydroquinone greatly inhibited sertraline-induced Ca²âº release. Inhibition of phospholipase C with U73122 abolished sertraline-induced [Ca²âº](i) rise. At concentrations of 5-50 µM, sertraline killed cells in a concentration-dependent manner. The cytotoxic effect of 25 µM sertraline was not reversed by prechelating cytosolic Ca²âº with BAPTA/AM. Collectively, in SIRC cells, sertraline induced [Ca²âº](i) rises by causing phospholipase C-dependent Ca²âº release from the endoplasmic reticulum and Ca²âº influx via phospholipase A2-sensitive Ca²âº channels. Sertraline-caused cytotoxicity was mediated by Ca²âº-independent pathways.
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Sinalização do Cálcio/fisiologia , Cálcio/metabolismo , Células Epiteliais/metabolismo , Epitélio Corneano/citologia , Epitélio Corneano/metabolismo , Sertralina/administração & dosagem , Animais , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Epitélio Corneano/efeitos dos fármacos , Coelhos , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagemRESUMO
Regenerative medicine is increasingly important in clinical practice. Ligamentum flava (LF) are typically removed during spine-related surgeries. LF may be a source of cells for spinal fusion that is conducted using tissue engineering techniques. In this investigation, LF cells of rabbits were isolated and then characterized by flow cytometry, morphological observation, and immunofluorescence staining. The LF cells were also cultivated in polyethylene (glycol) diacrylate (PEGDA) hydrogels that incorporated bone morphogenetic protein-2 (BMP-2) growth factor, to evaluate their proliferation and secretion of ECM and differentiation in vitro. The experimental results thus obtained that the proliferation, ECM secretion, and differentiation of the PEGDA-BMP-2 group exceeded those of the PEGDA group during the period of cultivation. The mineralization and histological staining results differed similarly. A nude mice model was utilized to prove that LF cells on hydrogels could undergo osteogenic differentiation in vivo. These experimental results also revealed that the PEGDA-BMP-2 group had better osteogenic effects than the PEGDA group following a 12 weeks after transplantation. According to all of these experimental results, LF cells are a source of cells for spinal fusion and PEGDA-BMP-2 hydrogel is a candidate biomaterial for spinal fusion by tissue engineering.
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Proteína Morfogenética Óssea 2/farmacologia , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Ligamento Amarelo/citologia , Luz , Osteogênese/efeitos dos fármacos , Fusão Vertebral , Animais , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Células Cultivadas , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos Nus , Osteogênese/genética , CoelhosRESUMO
This article studied the effects of platelet-rich plasma (PRP) on the potential of synovial fluid mesenchymal stem cells (SF-MSCs) to differentiate. The PRP and SF-MSCs were obtained from the blood and knees of pigs, respectively. The identification of SF-MSCs and their ability to differentiate were studied by histological and surface epitopes, respectively. The SF-MSCs can undergo trilineage mesenchymal differentiation under osteogenic, chondrogenic, and adipocyte induction. The effects of various PRP concentrations (0%, 20% and 50% PRP) on differentiation were evaluated using the SF-MSCs-alginate system, such as gene expression and DNA proliferation. A 50% PRP concentration yielded better differentiation than the 20% PRP concentration. PRP favored the chondrogenesis of SF-MSCs over their osteogenesis in a manner that depended on the ratios of type II collagen/type I collagen and aggrecan/osteopontin. Eventually, PRP promoted the proliferation of SF-MSCs and induced chondrogenic differentiation of SF-MSCs in vitro. Both PRP and SF-MSCs could be feasibly used in regenerative medicine and orthopedic surgeries.
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Condrogênese , Células-Tronco Mesenquimais/metabolismo , Plasma Rico em Plaquetas/metabolismo , Líquido Sinovial/citologia , Alginatos/química , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Feminino , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Células-Tronco Mesenquimais/citologia , SuínosRESUMO
M-3M3FBS (2,4,6-trimethyl-N-(meta-3-trifluoromethyl-phenyl)-benzenesulfonamide is a presumed phospholipase C activator which induced Ca²âº movement and apoptosis in different cell models. How- ever, the effect of m-3M3FBS on cytosolic free Ca²âº concentrations ([Ca²âº]i) and apoptosis in SCM1 human gastric cancer cells is unclear. This study explored whether m-3M3FBS elevated basal [Ca²âº]i levels in suspended cells by using fura-2 as a Ca²âº-sensitive fluorescent dye. M-3M3FBS at concentrations between 5-50 µM increased [Ca²âº]i in a concentration-dependent manner. The Ca²âº signal was reduced by half by removing extracellular Ca²âº. M-3M3FBS-induced Ca²âº influx was inhibited by nifedipine, econazole, SK&F96365, aristolochic acid, and GF109203X. In Ca²âº-free medium, 50 µM m-3M3FBS pretreatment inhibited the [Ca²âº]i rise induced by the endoplasmic reticulum Ca²âº pump inhibitor thapsigargin. Conversely, pretreatment with thapsigargin partly reduced m-3M3FBS-induced [Ca²âº]i rise. Suppression of inositol 1,4,5-trisphosphate production with U73122 did not change m-3M3FBS- induced [Ca²âº]i rise. At concentrations between 25 and 50 µM m-3M3FBS killed cells in a concentration- dependent manner. The cytotoxic effect of m-3M3FBS was not reversed by prechelating cytosolic Ca²âº with acetoxy-methyl ester of bis-(o-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid (BAPTA/AM). Annexin V/propidium iodide staining data suggest that m-3M3FBS induced apoptosis at 25 and 50 µM. M-3M3FBS also increased levels of superoxide. Together, in human gastric cancer cells, m-3M3FBS induced a [Ca²âº]i rise by inducing phospholipase C-independent Ca²âº release from the endoplasmic reticulum and Ca²âº entry via protein kinase C-sensitive store-operated Ca²âº channels. M-3M3FBS induced cell death that might involve apoptosis via reactive oxygen species production.
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Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Sulfonamidas/farmacologia , Fosfolipases Tipo C/fisiologia , Linhagem Celular Tumoral , Humanos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologiaRESUMO
OBJECTIVE: Treatment of early stage avascular necrosis of the femoral head (AVNFH) is still challenging for clinicians today. Core decompression with the implantation of mesenchymal stem cells (MSCs) has become popular and been proven to be an effective therapy for ANNFH. Synovial fluid MSCs, which can be easily harvested by joint aspiration, reportedly have the potential to differentiate into bone and cartilage. The purpose of this investigation is to evaluate the effectiveness of core decompression plus the implantation of alginate beads embedded with synovial fluid MSCs (ABSMSCs) in bone regeneration in the treatment of steroid-induced AVNFH in a rabbit model. METHODS: An in vitro study is carried out to evaluate the bioactivity and osteogenic differentiation of synovial fluid MSCs in the environment formed by alginate beads. In an in vivo study, the application of ABSMSCs was combined with bone decompression to treat steroid-induced AVNFH in a rabbit model. Bone mineral density, radiography and histology were used to evaluate the bone growth of the femoral head after the rabbits had been euthanized 6 weeks after surgery. RESULTS: The results obtained in vitro showed that the synovial fluid MSCs in the environment of alginate beads had the potential to differentiate toward bone growth. In vivo, the treatment of steroid-induced AVNFH in a rabbit model by core decompression plus the implantation of ABSMSCs preserved the bone density and sphericity of the femoral head and promoted bone regeneration. CONCLUSION: Implantation of ABSMSCs is a novel and effective therapy for AVNFH. Hopefully, this application will improve the outcome of early stage AVNFH and facilitate the harvesting of stem cells.
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Alginatos , Necrose da Cabeça do Fêmur/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Microesferas , Líquido Sinovial , Animais , Necrose da Cabeça do Fêmur/induzido quimicamente , Glucocorticoides/administração & dosagem , Ácido Glucurônico , Ácidos Hexurônicos , Humanos , Metilprednisolona/administração & dosagem , Coelhos , Líquido Sinovial/citologiaRESUMO
The COVID-19 pandemic has underscored the pivotal role of epidemiology in studying pathogenic agents [...].
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Microscopic examination of acid-fast mycobacterial bacilli (AFB) in sputum smears remains the most economical and readily available method for laboratory diagnosis of pulmonary tuberculosis (TB). However, this conventional approach is low in sensitivity and labor-intensive. An automated microscopy system incorporating artificial intelligence and machine learning for AFB identification was evaluated. The study was conducted at an infectious disease hospital in Jiangsu Province, China, utilizing an intelligent microscope system. A total of 1000 sputum smears were included in the study, with the system capturing digital microscopic images and employing an image recognition model to automatically identify and classify AFBs. Referee technicians served as the gold standard for discrepant results. The automated system demonstrated an overall accuracy of 96.70% (967/1000), sensitivity of 91.94% (194/211), specificity of 97.97% (773/789), and negative predictive value (NPV) of 97.85% (773/790) at a prevalence of 21.1% (211/1000). Incorporating AI and machine learning into an automated microscopy system demonstrated the potential to enhance the sensitivity and efficiency of AFB detection in sputum smears compared to conventional manual microscopy. This approach holds promise for widespread application in TB diagnostics and potentially other fields requiring labor-intensive microscopic examination.
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Aims: Several artificial bone grafts have been developed but fail to achieve anticipated osteogenesis due to their insufficient neovascularization capacity and periosteum support. This study aimed to develop a vascularized bone-periosteum construct (VBPC) to provide better angiogenesis and osteogenesis for bone regeneration. Methods: A total of 24 male New Zealand white rabbits were divided into four groups according to the experimental materials. Allogenic adipose-derived mesenchymal stem cells (AMSCs) were cultured and seeded evenly in the collagen/chitosan sheet to form cell sheet as periosteum. Simultaneously, allogenic AMSCs were seeded onto alginate beads and were cultured to differentiate to endothelial-like cells to form vascularized bone construct (VBC). The cell sheet was wrapped onto VBC to create a vascularized bone-periosteum construct (VBPC). Four different experimental materials - acellular construct, VBC, non-vascularized bone-periosteum construct, and VBPC - were then implanted in bilateral L4-L5 intertransverse space. At 12 weeks post-surgery, the bone-forming capacities were determined by CT, biomechanical testing, histology, and immunohistochemistry staining analyses. Results: At 12 weeks, the VBPC group significantly increased new bone formation volume compared with the other groups. Biomechanical testing demonstrated higher torque strength in the VBPC group. Notably, the haematoxylin and eosin, Masson's trichrome, and immunohistochemistry-stained histological results revealed that VBPC promoted neovascularization and new bone formation in the spine fusion areas. Conclusion: The tissue-engineered VBPC showed great capability in promoting angiogenesis and osteogenesis in vivo. It may provide a novel approach to create a superior blood supply and nutritional environment to overcome the deficits of current artificial bone graft substitutes.
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Background: The use of magnetic resonance linear accelerators (MR-LINACs) for clinical treatment has opened up new possibilities and challenges in the field of radiation oncology. However, annual quality assurance (QA) is relatively understudied due to practical considerations. Thus, to overcome the difficulty of measuring the dose with a small water phantom for TRS-398 or TG-51 in all external beam radiation treatment unit environments, such as MR compatibility, we designed a remote phantom with a three-axis changeable capacity for QA. Methods: The designed water phantom was tested under an MR environment. The water phantom system comprised of three parts: a phantom box, a dose measurement tool, and a PMD401 drive system. The UNIDOSE universal dosimeter was used to collect beam data. The manufacturer's developer tools were utilized to position the measurement. To ensure magnetic field homogeneity, a distortion phantom was prepared using sixty fish oil capsules aligned radially to distinguish the oil and free air. The phantom was scanned in both the MR simulator and computed tomography (CT), and the acquired images were analyzed to determine the position shift. Results: The dimensions of the device are 30 cm in the X-axis, 20 cm in the Y-axis, and 17 cm in the Z-axis. Total cost of materials was no more than $10,000 US dollars. Our results indicate that the device can function normally in a regular 1.5 T MR environment without interference from the magnetic field. The water phantom's traveling speed was found to be approximately 5 mm/s with a position difference confined within 6 cm intervals during normal use. The distortion test results showed that the prepared MR environment has uniform magnetic field homogeneity. Conclusions: In this study, we constructed a prototype water phantom device that can function in an MR simulator without interference between the magnetic field and electronic components. Compared to other commercially available MR-LINAC water phantoms, our device offers a more cost-effective solution for routine monthly QA. It can shorten the duration of QA tests and relieve the burden on medical physicists.
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Using low-energy electron diffraction and angle-resolved photoemission spectroscopy, we investigated the lattice and electronic structures of the Pb(111) surface upon the adsorption of Au atoms at the low temperature T = 40 K. Unlike earlier results showing the formation of PbAu-alloy layers at room temperature, we found that Au atoms form a ultra-thin superstructure, Au/Pb(111)-3 × 3, on top of the Pb(111) surface. Moreover, three surface-state bands, S1, S2, and S3, are induced within and immediately adjacent to the Pb bulk projected band gap centered at the surface zone boundary [Formula: see text] at the energies of - 0.02, - 1.05, and - 2.56 eV, respectively. First-principles calculation based on Au/Pb(111)-3 × 3 confirms the measured surface-state bands among which the most interesting are the S1 and S3 surface states. They are derived from surface resonances in Pb(111). Moreover, S1, which disperses across Fermi level, exhibits a large anisotropic Rashba splitting with α of 1.0 and 3.54 eVÅ in the two symmetry directions centered at [Formula: see text]. The corresponding Rashba splitting of S1 band in Cu/Pb(111)-3 × 3 and Ag/Pb(111)-3 × 3 were calculated for comparison.
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Plumbene, with a structure similar to graphene, is expected to possess a strong spin-orbit coupling and thus enhances its superconducting critical temperature (Tc ). In this work, a buckled plumbene-Au Kagome superstructure grown by depositing Au on Pb(111) is investigated. The superconducting gap monitored by temperature-dependent scanning tunneling microscopy/spectroscopy shows that the buckled plumbene-Au Kagome superstructure not only has an enhanced Tc with respect to that of a monolayer Pb but also possesses a higher value than what owned by a bulk Pb substrate. By combining angle-resolved photoemission spectroscopy with density functional theory, the monolayer Au-intercalated low-buckled plumbene sandwiched between the top Au Kagome layer and the bottom Pb(111) substrate is confirmed and the electron-phonon coupling-enhanced superconductivity is revealed. This work demonstrates that a buckled plumbene-Au Kagome superstructure can enhance superconducting Tc and Rashba effect, effectively triggering the novel properties of a plumbene.
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BACKGROUND: Histone deacetylase (HDAC) inhibitors have emerged as a new class of antitumor agents because they were demonstrated to induce cell cycle arrest, promote cell apoptosis, and inhibit metastasis. Recently, HDAC inhibitors were also shown to exhibit pronounced anti-inflammatory properties. However, the underlying mechanism contributing to the suppression of inflammatory responses by HDAC inhibitors remains to be fully defined. In the present study, we explored the actions of trichostatin A (TSA), a potent HDAC inhibitor, on lipopolysaccharide (LPS)-induced cyclooxygenase (COX)-2 expression in human umbilical vascular endothelial cells (HUVECs). METHODS: HUVECs were exposed to LPS in the absence or presence of TSA. COX-2 expression and signaling molecules (JNK, p38MAPK and c-jun) activated by LPS were assessed. RESULTS: The LPS-induced cox-2 messenger RNA and protein were markedly suppressed by TSA. TSA inhibited JNK and p38MAPK phosphorylation in cells exposed to LPS. Treatment of cells with a JNK signaling inhibitor (JNK inhibitor II) or a p38MAPK inhibitor (p38MAPK inhibitor III) markedly inhibited LPS-induced COX-2 expression. TSA suppression of JNK and p38MAPK phosphorylation and subsequent COX-2 expression were restored by selective inhibition of MKP-1 using MKP-1 siRNA. In addition, TSA caused an increase in MKP-1 phosphatase activity in HUVECs. In conclusion, TSA may cause MKP-1 activation to dephosphorylate JNK and p38MAPK, leading to the downregulation of COX-2 in HUVECs stimulated by LPS, a proinflammatory stimulus. GENERAL SIGNIFICANCE: MKP-1 contributes to TSA's protective actions in HUVECs exposed to LPS. The present study also supports the therapeutic value of TSA in treating inflammatory vascular diseases.
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Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Fosfatase 1 de Especificidade Dupla/metabolismo , Endotélio Vascular/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Veias Umbilicais/efeitos dos fármacos , Sequência de Bases , Western Blotting , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Primers do DNA , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Humanos , Fosforilação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Veias Umbilicais/citologia , Veias Umbilicais/enzimologiaRESUMO
UNLABELLED: Increased breastfeeding was suggested as a contributing factor to significant hyperbilirubinemia. The aim of this study was to identify the risk factors associated with jaundice in exclusively breastfed term neonates. We retrospectively reviewed all consecutively live-born neonates from August 2009 to July 2010 who had complete outpatient department (OPD) follow-up at ≤14 days old. Hyperbilirubinemia was defined as a transcutaneous bilirubin (TcB) value of ≥15 mg/dl. During the study period, there were 718 deliveries, of which 152 neonates were transferred to the special care nursery or neonatal intensive care unit; 566 neonates were discharged from the nursery, and 243 neonates were excluded: 83 did not return to the OPD, 46 were older than 14 days at OPD follow-up, 44 were <37 weeks of gestational age, and 70 had been fed formula. In total, 323 neonates were enrolled and classified into the hyperbilirubinemic (114 neonates) and non-hyperbilirubinemic groups (209 neonates). The gender, gestational age, Apgar score, age at nursery discharge, birth weight, and body weight at nursery discharge and at OPD were comparable between the two groups. TcB values at nursery discharge were positively correlated with TcB values in the OPD. Infants with hyperbilirubinemia exhibited significantly greater body weight loss from birth to the OPD follow-up and significantly less body weight gain from nursery discharge to OPD follow-up. CONCLUSION: High TcB values at nursery discharge and a smaller body weight gain are associated with hyperbilirubinemia in term neonates who are exclusively breastfed.