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2.
Curr Pharm Des ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31942857

RESUMO

BACKGROUND: Guidelines have previously suggested that atrial fibrillation (AF) is associated with an increased risk of arrhythmic death in Brugada syndrome (BrS) patients. However, only two articles consisting of 17 AF patients with BrS supported these views. The risk stratification of BrS patients with AF remains controversial. Thus, we performed a meta-analysis to estimate the risk stratification of BrS patients with AF. METHODS: We searched relevant studies published from 2000 to December 30, 2018. A total of 1712 patients with BrS from five studies were included: 200 patients (12%) were reported with AF, among whom 37 patients (19%) had arrhythmic events. RESULTS: BrS patients with AF in all studies (OR 1.92, 95% CI:0.91to 4.04, P =0.09; Heterogeneity: P = 0.03, I2=61%)and some European studies (OR 1.12, 95% CI: 0.18 to 6.94, P=0.91; Heterogeneity: P = 0.006, I2=80%) did not display a higher risk of arrhythmic events than those without AF, but BrS patients with AF in Japanese studies (OR 2.32, 95% CI: 1.37 to 3.93, P=0.002; Heterogeneity: P = 0.40, I2=0%) had a higher risk of arrhythmic events than those without AF. The proportion of BrS patients with AF was greater in Japanese studies than in some European studies (16% vs. 9%, P<0.001). CONCLUSIONS: On the whole, BrS patients with AF showed no higher risk of arrhythmic events than those without AF, but BrS patients with AF in Japan had a higher risk of arrhythmic events than those without AF.

3.
J Membr Biol ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31820013

RESUMO

Lysophosphatidylcholine (LPC) is a major atherogenic lipid that stimulates an increase in mitochondrial reactive oxygen species (mtROS) and the release of cytokines under inflammasome activation. However, the potential receptors of LPC in macrophages are poorly understood. Members of the transient receptor potential (TRP) channel superfamily, which is crucially involved in transducing environmental irritant stimuli into nociceptor activity, are potential receptors of LPC. In this study, we investigated whether LPC can induce the activation of transient receptor potential ankyrin 1 (TRPA1), a member of the TRP superfamily. The functional expression of TRPA1 was first detected by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting and calcium imaging in human acute monocytic leukemia cell line (THP-1)-derived macrophages. The mechanism by which LPC induces the activation of macrophages through TRPA1 was verified by cytoplasmic and mitochondrial calcium imaging, mtROS detection, a JC-1 assay, enzyme-linked immunosorbent assay, the CCK-8 assay and the lactate dehydrogenase (LDH) cytotoxic assay. LPC induced the activation of THP-1-derived macrophages via calcium influx, and this activation was suppressed by potent and selective inhibitors of TRPA1. These results indicated that TRPA1 can mediate mtROS generation, mitochondrial membrane depolarization, the secretion of IL-1ß and cytotoxicity through cellular and mitochondrial Ca2+ influx in LPC-treated THP-1-derived macrophages. Therefore, the inhibition of TRPA1 may protect THP-1-derived macrophages against LPC-induced injury.

4.
Acta Crystallogr C Struct Chem ; 75(Pt 12): 1690-1697, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802760

RESUMO

The new asymmetrical organic ligand 2-{4-[(1H-imidazol-1-yl)methyl]phenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazole (L, C17H13N5O), containing pyridine and imidazole terminal groups, as well as potential oxdiazole coordination sites, was designed and synthesized. The coordination chemistry of L with soft AgI, CuI and CdII metal ions was investigated and three new coordination polymers (CPs), namely, catena-poly[[silver(I)-µ-2-{4-[(1H-imidazol-1-yl)methyl]phenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazole] hexafluoridophosphate], {[Ag(L)]PF6}n, catena-poly[[copper(I)-di-µ-iodido-copper(I)-bis(µ-2-{4-[(1H-imidazol-1-yl)methyl]phenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazole)] 1,4-dioxane monosolvate], {[Cu2I2(L)2]·C4H8O2}n, and catena-poly[[[dinitratocopper(II)]-bis(µ-2-{4-[(1H-imidazol-1-yl)methyl]phenyl}-5-(pyridin-4-yl)-1,3,4-oxadiazole)]-methanol-water (1/1/0.65)], {[Cd(L)2(NO3)2]·2CH4O·0.65H2O}n, were obtained. The experimental results show that ligand L coordinates easily with linear AgI, tetrahedral CuI and octahedral CdII metal atoms to form one-dimensional polymeric structures. The intermediate oxadiazole ring does not participate in the coordination interactions with the metal ions. In all three CPs, weak π-π interactions between the nearly coplanar pyridine, oxadiazole and benzene rings play an important role in the packing of the polymeric chains.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31836984

RESUMO

A complete orthogonal experiment using a pot test is conducted to investigate the effects of four amendments (biochar, peat, manure, and non-contaminated soil (NCS)) on the metal availability, mobility, and phytostabilization potential of an energy crop, king grass (Pennisetum purpureum × P. thyphoideum), in Pb/Zn mine tailings. The addition of amendments significantly increased the pH and fertility of the tailings, while significantly decreasing the heavy metal available contents in the tailings. The available Cd, Pb, Zn, and As concentrations in the tailings in the treatment amended with biochar+NCS+peat+manure were 51.00%, 36.62%, 50.57%, and 75.88%, respectively, lower than those in the treatment control. The king grass survived in the tailings without amendments, while amendments made the plant grow well or better in the tailings than in NCS. The addition of amendments significantly reduced the content of heavy metals and bioaccumulation factor (BCF) in the plant root but increased the translocation factor (TF) of Cd, Zn, and As and had little effect on the TF of Pb. The TF for heavy metals in plant were lower than one for all of the treatments. During a leaching period of 30 days, the pH of the leachate declined slowly and then maintained at 6.0~6.6. The addition of the amendments significantly reduced the metal concentrations of the leachates, and the highest declines were 50.46%, 20.04%, 41.58%, and 47.04% for Cd, Pb, Zn, and As, respectively. Biochar had a higher immobilization capacity for Cd, Pb, Zn, and As than manure, peat, and NCS. King grass could be used to aid phytostabilization for Cd- and Pb-polluted tailings, and biochar-rich amendments were effective for the in situ immobilization of metals. Further field monitoring is necessary to demonstrate the effectiveness of king grass and amendments under the climatic conditions of China.

6.
Life Sci ; : 117178, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31862452

RESUMO

AIMS: Odontoblasts play essential functions in dentinal repair, and therefore, many researchers have been interested in exploring new ways of promoting odontoblast generation. The present study aimed to identify the potential role of the glioma-associated oncogene protein-2 (GLI2) in the differentiation of human dental pulp stem cells (hDPSCs) into odontoblast-like cells. MAIN METHODS: hDPSCs were sorted from dental pulp cells by magnetic-activated cell sorting. Next, the differentiation of hDPSCs into odontoblast-like cells was measured by detecting mineralized nodule formation, differentiation markers dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP-1) and downstream transcription factors of the Wnt/ß-catenin signaling pathway. GLI2 expression was measured during hDPSC differentiation into odontoblast-like cells. The effects of GLI2 in the process of differentiation of hDPSCs into odontoblast-like cells with the involvement of the Wnt/ß-catenin signaling pathway were evaluated by silencing GLI2 and activating the Wnt/ß-catenin signaling pathway in hDPSCs. KEY FINDINGS: It was observed that GLI2 was up-regulated during hDPSC differentiation into odontoblast-like cells, which was proved to enhance the differentiation of hDPSCs into odontoblast-like cells. Moreover, the Wnt/ß-catenin signaling pathway was activated by GLI2. The activity of ALP, expression of DMP-1 and DSPP and the number of mineralized nodules were increased in hDPSCs cultured in osteogenic medium. Overexpression of GLI2 promoted the differentiation of hDPSCs into odontoblast-like cells by activating the Wnt/ß-catenin signaling pathway. SIGNIFICANCE: Taken together, the present study showed that GLI2 was positively correlated with the differentiation of hDPSCs into odontoblast-like cells, which might provide a potential biomarker for the treatment of tooth damage.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31751215

RESUMO

OBJECTIVE: Breast cancer is the most common type of invasive cancer and one of the leading causes of cancer death in women worldwide. Correct staging of breast cancer is critical to the survival rate of the patients. Sentinel lymph node (SLN) biopsy (SLNB), currently the gold standard technique for breast cancer staging, requires preoperative and intraoperative image guidance for noninvasive SLN identification and minimal surgical invasion. However, existing image guidance techniques suffer from a variety of limitations, such as ionizing radiation, high cost, and poor imaging depth. To address the clinical challenges, new methodology has to be developed. METHODS: We developed a photoacoustic (PA) imaging procedure for noninvasive and nonradioactive SLN identification and biopsy guidance enhanced with a clinically-approved lymphatic tracer, i.e., carbon nanoparticles (CNPs) suspension injection. RESULTS: In vivo experiments show that the proposed procedure could sensitively identify the SLN and provide high-contrast image guidance for fine-needle aspiration simulation. In addition, we demonstrated that CNPs have significantly better performance than other commonly-used contrast agents, such as methylene blue and indocyanine green. CONCLUSION: PA imaging technique using clinically-approved CNPs as the contrast agent is capable for noninvasive and nonradioactive SLN identification and high-contrast biopsy guidance, and should be considered as a new tool for assisting SLNB in breast cancer staging. SIGNIFICANCE: The proposed CNPs-enhanced PA imaging technique provides a practical way for SLN identification and biopsy guidance for breast cancer patients and paves the way for clinical translation of PA SLN imaging.

8.
Heart Fail Rev ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31745841

RESUMO

Recently, several studies have demonstrated that heart failure (HF) may increase the risk of incident cancer. However, this association has not been statistically and systematically verified by any comprehensive pooled analyses. We performed a meta-analysis on cancer morbidity and co-mortality of adults with HF in a large sample size to explore the relationship between HF and the risk of developing cancer. From inception to April 2019, we searched PubMed and EMBASE for published relevant articles on patients with HF diagnosed with cancer afterwards, with reported outcomes of morbidity and mortality. Two investigators independently reviewed these included studies. Study data were independently extracted using predefined data extraction forms. Random and fixed-effects models were fit for the study duration. This analysis consisted of 4 cohort studies comprising 5,004,251 participants. The relative risk (RR) for incident cancer was 1.22 (95% confidence interval (CI), 1.13-1.33) indicating that patients with HF may have a higher risk of developing cancer. The pooled RR of co-mortality was 2.03 (95% CI, 1.13-3.65), indicating that HF associated with cancer increases the risk of mortality. In this meta-analysis and systematic review, our results demonstrated that heart failure may increase the risk of incident cancer and that HF associated with cancer increases the risk of mortality.

9.
Front Pharmacol ; 10: 1133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31680944

RESUMO

Background: Ischemic stroke (IS) is a leading cause of death and long-term disability worldwide. The NaoShuanTong capsule (NSTC), a traditional Chinese patent medicine, has been extensively used in the treatment of stroke in China. However, the clinical efficacy and safety of this treatment has not been statistically and systematically verified by any comprehensive pooled analysis. We therefore performed a meta-analysis to evaluate the efficacy and safety of NSTC in the treatment of IS. Methods: Randomized controlled trials (RCTs) of NSTC in the treatment of IS conducted before September 2018 were retrieved from five databases, according to specific inclusion and exclusion criteria. Two investigators independently reviewed the included studies and extracted relevant data. The methodological quality of the included studies was assessed using criteria from the Cochrane Handbook, and analyzed using Review Manager 5.3 software. Results: Thirteen RCTs comprising a total of 1,360 participants were included in this study. NSTC was shown to significantly improve the overall response rate (OR = 3.04, 95% CI [1.76, 5.26], P < 0.00001), and neurological function (NSTC increased Modified Barthel Index (MD = 8.15, 95% CI [3.79, 12.52], P = 0.0005), Functional Independence Measure (MD = 29.61, 95% CI [10.11, 49.10], P = 0.003) and European Stroke Scale scores (MD = 8.51, 95% CI [7.00, 10.01], P = 0.03). In addition, NSTC significantly increased serum adiponectin level (MD = 0.66, 95% CI [0.23, 1.08], P = 0.002). Moreover, NSTC reduced atherosclerotic plaque area (MD = -2.24, 95% CI [-4.02, -0.46], P = 0.01) and intima-media thickness (MD = -0.09, 95% CI [-0.13, -0.05], P < 0.0001). However, there was no significant difference between NSTC treatment and conventional therapy with respect to Fugl-Meyer Assessment score (MD = 10.59, 95% CI [-1.78, 22.96], P = 0.09) or Crouse score (MD = -0.78, 95% CI [-1.79, -0.22], P = 0.13). Conclusions: The results of this meta-analysis showed that NSTC exhibits efficacy in the treatment of cerebral infarction. NSTC can improve the overall response rate and neurological function, increase blood adiponectin, reduce neurological deficits, and decrease atherosclerotic plaque area.

10.
Aging (Albany NY) ; 11(19): 8270-8293, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31586988

RESUMO

Left- and right-sided colon cancer (LC and RC) differ substantially in their molecular characteristics and prognoses, and are thus treated using different strategies. We systematically analyzed alternative splicing (AS) events and splicing factors in LC and RC. RNA-seq data were used for genome-wide profiling of AS events that could distinguish LC from RC. The Exon Skip splicing pattern was more common in RC, while the Retained Intron pattern was more common in LC. The AS events that were upregulated in RC were enriched for genes in the axon guidance pathway, while those that were upregulated in LC were enriched for genes in immune-related pathways. Prognostic models based on differentially expressed AS events were built, and a prognostic signature based on these AS events performed well for risk stratification in colon cancer patients. A correlation network of differentially expressed AS events and differentially expressed splicing factors was constructed, and RBM25 was identified as the hub gene in the network. In conclusion, large differences in AS events may contribute to the phenotypic differences between LC and RC. The differentially expressed AS events reported herein could be used as biomarkers and treatment targets for colon cancer.

11.
Stem Cell Res ; 40: 101571, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31520889

RESUMO

Autism spectrum disorder (ASD) is a neurological disorder with complex etiologies. In this study, urine cells were collected from a 16-year-old male with ASD and reprogrammed with the human SKOM transcription factors. The patient has a heterozygous C > T mutation of FCGR1B gene that was confirmed by sequencing analysis. The pluripotency was verified by gene expression and capacity of differentiation towards the three germ layers. This kind of iPSC will be valuable for further understanding the pathogenesis of ASD and help to develop drugs for treating ASD.

12.
Eur J Med Chem ; 183: 111679, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541870

RESUMO

Anti-tubulin polymerization agents can disrupt tumor-vascular to exhibit anti-cancer potency. In this study, a series of substituted (2-(phenylamino)thieno[3,2-d]pyrimidin-4-yl)(3,4,5-trimethoxyphenyl)methanone analogues were designed and synthesized as anti-tubulin polymerization agents that interact with colchicine binding site. The anti-proliferative assay indicated that most of the target compounds displayed moderate to high potencies towards five tumor cell lines. The structure-activity relationship of these analogues was summarized. The most potent compound 14 was selected to assay its inhibition on the tubulin polymerization. 14 displayed potent inhibition against tubulin polymerization with an IC50 value of 4.1 ±â€¯0.1 µM. The colchicine competition assay demonstrated that 14 inhibited tubulin polymerization by binding to the colchicine-binding site of tubulin. The molecular modeling study elucidated the binding mode of 14 in the colchicine binding site. The result of confocal immunofluorescent study proved that 14 can quickly disrupt the microtubules of Hela cells in a concentration dependent manner. Some experiments at cellular level were conducted to investigate the effects of 14 on cellular morphology, cell colony formation, cell cycle distribution, cell apoptosis and mitochondrial changes. The results demonstrated that 14 is a potent anti-tubulin agent with strong concentration dependent effect of inhibition of colony formation, induction of G2/M arrest and induction of apoptosis through mitochondrial pathway.

13.
J Org Chem ; 84(21): 14241-14247, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31535555

RESUMO

A general visible-light mediated ortho-C-H trifluoromethylation of aniline derivatives by using a low-cost and stable Langlois reagent (CF3SO2Na) as the "CF3" source has been developed. In contrast to previous reports, this strategy allowed access to elusive trifluoromethyl lactams. Furthermore, mechanism experiments revealed that a copper/photoredox dual catalytic mechanism enabled general trifluoromethylation of aniline derivatives.

14.
J Biophotonics ; 12(12): e201900212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31407486

RESUMO

Needle placement is important for many clinical interventions, such as tissue biopsy, regional anesthesia and drug delivery. It is essential to visualize the spatial position of the needle and the target tissue during the interventions using appropriate imaging techniques. Based on the contrast of optical absorption, photoacoustic imaging is well suited for the guidance of interventional procedures. However, conventional photoacoustic imaging typically provides two-dimensional (2D) slices of the region of interest and could only visualize the needle and the target when they are within the imaging plane of the probe at the same time. This requires great alignment skill and effort. To ease this problem, we developed a 3D interventional photoacoustic imaging technique by fast scanning a linear array ultrasound probe and stitching acquired image slices. in vivo sentinel lymph node biopsy experiment shows that the technique could precisely locate a needle and a sentinel lymph node in a tissue volume while a perfusion experiment demonstrates that the technique could visualize the 3D distribution of injected methylene blue dye underneath the skin at high temporal and spatial resolution. The proposed technique provides a practical way for photoacoustic image-guided interventions.

15.
Front Immunol ; 10: 1592, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354731

RESUMO

The nod-like receptor family pyrin domain containing 3 (NLRP3) is currently the most widely studied inflammasome and has become a hot topic of recent research. As a macromolecular complex, the NLRP3 inflammasome is activated to produce downstream factors, including caspase-1, IL-1ß, and IL-18, which then promote local inflammatory responses and induce pyroptosis, leading to unfavorable effects. A growing number of studies have examined the relationship between the NLRP3 inflammasome and cardiovascular diseases (CVDs). However, some studies have shown that the NLRP3 inflammasome is not involved in the occurrence of certain diseases. Therefore, identifying the mechanism of action of the NLRP3 inflammasome and its potential involvement in the pathological process of disease progression is of utmost importance. This review discusses the mechanisms of NLRP3 inflammasome activation and the relationship between the inflammasome and CVDs, including coronary atherosclerosis, myocardial ischemia/reperfusion, cardiomyopathies, and arrhythmia, as well as CVD-related treatments.

16.
Psychiatry Res ; 278: 173-179, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207454

RESUMO

To improve understanding of treatment-resistant depression (TRD) in a large population of individuals with depression, a self-reported antidepressant efficacy survey was designed and administered to 23andMe research participants. Participants with a current depressive episode or with a depressive episode within the last 5 years were queried for the effect of pharmacotherapy during the episode. TRD was defined as non-response to at least two antidepressants taken for at least 5-6 weeks. Non-TRD (NTRD) was defined as responsive to either the first or second medication taken for at least 3-4 weeks. Participants who could not be classified as TRD or NTRD were excluded from the analysis. Approximately 56,000 participants completed the survey, among which approximately 33,000 took medication for a depressive episode. The 3409 participants with self-reported TRD tended to have younger age of onset, and a more persistent course prior to initiation of treatment (e.g., a longer prior average episode duration and residual symptoms between episodes) than the 18,511 participants classified as NTRD. This survey identified depression characteristics, comorbidities, trigger events, and early childhood trauma that distinguish TRD from NTRD.

17.
Eur J Med Chem ; 171: 420-433, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30928712

RESUMO

(E)-3,4-dihydroxystyryl alkyl sulfones, as new analogues of neurodegenerative agents, were designed and synthesized. The biological results demonstrated that most of the target compounds preserved antioxidant and anti-inflammatory potency in scavenging reactive free radicals, protecting neuronal cells against neurotoxins such as H2O2, 6-hydroxydopamine and inhibiting lipopolysaccharide (LPS)-induced over-production of NO. Among these compounds, 6.22 with cyclopentyl propyl exhibited prominent antioxidant activity at low concentration (2.5 µM) in H2O2 model (cell viability = 94.5%). In addition, 6.22 (IC50 = 1.6 µM) displayed better anti-inflammatory activity than that of lead compound 1 (IC50 = 13.4 µM). In view of the outstanding performance of 6.22, the apoptotic rates of H2O2-damaged PC12 cells were detected by Annexin V-FITC/PI assay. 6.22 showed higher potency in inhibition of apoptosis than 1 at low concentration (2.5 µM), consisting with the antioxidant and anti-inflammatory models. Furthermore, with the predicted CNS (+) blood-brain barrier (BBB) permeability (Pe = 6.84 × 10-6 cm s-1), low cytotoxicity and favorable physiochemical properties based on calculation, compound 6.22 can be further developed as a potential multifunctional neuroprotective agent.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Antioxidantes/síntese química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/antagonistas & inibidores , Linhagem Celular , Relação Dose-Resposta a Droga , Peróxido de Hidrogênio/farmacologia , Camundongos , Estrutura Molecular , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Permeabilidade/efeitos dos fármacos , Picratos/antagonistas & inibidores , Ratos , Relação Estrutura-Atividade
18.
Sci Rep ; 9(1): 5945, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30976009

RESUMO

Multimodal imaging with photoacoustic microscopy (PAM) and optical coherence tomography (OCT) can be an effective method to evaluate the choroidal and retinal microvasculature. To improve the efficiency for visualizing capillaries, colloidal gold nanoparticles (AuNPs) have been applied as a multimodal contrast agent for both OCT and PAM imaging by taking advantage of the strong optical scattering and the strong optical absorption of AuNPs due to their surface plasmon resonance. Ultra-pure AuNPs were fabricated by femtosecond laser ablation, capped with polyethylene glycol (PEG), and administered to 13 New Zealand white rabbits and 3 Dutch Belted pigmented rabbits. The synthesized PEG-AuNPs (20.0 ± 1.5 nm) were demonstrated to be excellent contrast agents for PAM and OCT, and do not demonstrate cytotoxicity to bovine retinal endothelial cells in cell studies. The image signal from the retinal and choroidal vessels in living rabbits was enhanced by up to 82% for PAM and up to 45% for OCT, respectively, by the administered PEG-AuNPs, which enables detection of individual blood vessels by both imaging modalities. The biodistribution study demonstrated the AuNP accumulated primarily in the liver and spleen. Histology and TUNEL staining did not indicate cell injury or death in the lung, liver, kidney, spleen, heart, or eyes up to seven days after AuNP administration. PEG-AuNPs offer an efficient and safe contrast agent for multimodal ocular imaging to achieve improved characterization of microvasculature.

19.
J Nanosci Nanotechnol ; 19(9): 5435-5440, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30961693

RESUMO

Vitamin D plays a major role in the regulation of calcium homeostasis and affects bone metabolism. There is currently limited detailed knowledge about the vitamin D endocrine system in human bone cells. Here, we investigated the direct effects of 1α, 25-dihydroxyvitamin D3 (1α, 25-(OH)2D3 or 'VD3') on osteogenesis of human umbilical cord mesenchymal stem cells (HUCMSCs). We also studied the impact of VD3 on intracellular Ca2+ concentrations in osteogenic cells. The results of alizarin red staining and alkaline phosphatase activity tests showed that VD3 could not induce osteogenic differentiation in HUCMSCs. However, addition of VD3 to the osteogenic differentiationinducing medium could promote HUCMSC to differentiate into osteoblasts. Calcium imaging showed that the addition of VD3 increased intracellular Ca2+ concentrations in osteogenic HUCMSCs. Thus, we concluded that adding VD3 increased intracellular Ca2+ concentrations in osteogenic HUCMSCs and promoted their osteogenesis.

20.
Rev Sci Instrum ; 90(3): 033504, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30927823

RESUMO

The injecting time of the picosecond laser in an indirect-drive integrated fast ignition experiment was measured by using an x-ray streak camera. Despite overlapping spatially and temporally in experiments, the soft x-ray signal from the nanosecond laser ablating the inner wall of an Au hohlraum and the hard x-ray signal from the bremsstrahlung radiation of hot electrons generated by a picosecond laser were separated by different image processes by filtering and collimating the two signals differently. The time sequence between the two x-ray signals was analyzed to extract the injection time of the picosecond laser relative to the hohlraum emission. By tracking the neutron yield as a function of the injection time of the picosecond laser, a clear positive correlation between the neutron yield enhancement and the derived injection times was exhibited. The heating effect of the picosecond laser was confirmed. It is concluded that this method could be used to measure the injecting time and validate the picosecond laser injection.

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