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1.
Org Lett ; 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32237750

RESUMO

Alternarin A (1), a rearranged drimane meroterpenoid characterized by a thioglycerate moiety, was isolated together with two known analogues from the coral-associated fungi Alternaria sp. ZH-15. Its structure was determined based on spectroscopic analysis, modified Mosher's method, and TDDFT/ECD calculations. In a primary cultured cortical neuronal network, compound 1 effectively inhibited the activity of spontaneous synchronous Ca2+ oscillations and 4-aminopyridine induced epileptic discharges in the low micromolar concentration range.

2.
BMC Musculoskelet Disord ; 21(1): 152, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143615

RESUMO

BACKGROUND: Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare genetic disorder characterized by extraskeletal heterotopic ossification. It is well recognized that FOP can lead to a devastating condition of disability. However, the mortality rate of FOP patients in China and risk factors for mortality are still largely unclear. METHODS: We conducted a retrospective research on a cohort of 65 cases of FOP patients in China from 2008 to 2018. We reviewed medical records of these FOP patients to retrieve information such as date of birth/death, gender, clinical features, genotypes and biochemical parameters and analyze the correlation of these parameters with the mortality. RESULTS: 92.3% (60/65 cases) patients were classic FOP patients, 3.1% (2/65 cases) were FOP-plus and 4.6% (3/65 cases) were FOP variants. 9 cases of this cohort were dead during the ten-year period, and the overall mortality rate was 13.8%. c.617G > A mutation was confirmed in all non-survivors. In FOP patients≤18 years at diagnosis, non-survivors demonstrated significantly lower blood osteocalcin and alkaline phosphatase levels compared with survivors (P < 0.05), and spearman correlation and logistic regression analysis indicated that serum osteocalcin and alkaline phosphatase levels were negatively correlated with the mortality. Furthermore, the receiver-operating characteristic curve analysis showed serum osteocalcin had the largest area under the curve of 0.855 among four biochemical parameters, and serum osteocalcin < 65.9 ng/ml displayed a good capacity to discriminate the non-survivors from survivors in FOP patients aged 18 years and younger at diagnosis. CONCLUSIONS: Our findings showed that the mortality rate of FOP was 13.8% in China. Serum OC level was negatively correlated with the mortality in Chinese FOP patients ≤18 years at diagnosis.

3.
Nat Rev Clin Oncol ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32112054

RESUMO

The presence of tumour-infiltrating lymphocytes (TILs) is associated with favourable outcomes in patients with breast cancer as well as in those with other solid tumours. T cells make up a considerable proportion of TILs and current evidence suggests that CD8+ T cells are a crucial determinant of favourable clinical outcomes. Studies involving tumour material from numerous solid tumour types, including breast cancer, demonstrate that the CD8+ TILs include a subpopulation of tissue-resident memory T (TRM) cells. This subpopulation has features consistent with those of TRM cells, which have been described as having a role in peripheral immune surveillance and viral immunity in both humans and mice. Patients with early-stage triple-negative breast cancers harbouring greater numbers of TRM cells have a substantially improved prognosis and longer overall survival. Furthermore, patients with advanced-stage breast cancers with higher levels of TRM cells have increased response rates to anti-PD-1 antibodies. These findings have motivated efforts to explore whether CD8+ TRM cells include tumour-specific T cells, their functional responses to cognate antigens and their role in responses to immune checkpoint inhibition. In this Review, we focus on the clinical significance of CD8+ TRM cells and the potential ways that these cells can be targeted to improve the success of immunotherapeutic approaches in patients with breast cancer, as well as in those with other solid tumour types.

4.
Chemosphere ; 251: 126392, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32146191

RESUMO

Emerging evidence indicated that disruption of circadian rhythm (CR) induced metabolic disorders, including dysregulation of energy homeostasis and lipid dysfunction, which was associated with ambient fine particulate matter (PM2.5) as well. However, the role and mechanism of CR in PM2.5-mediated metabolic disorder remain unknown. In the present study, we investigated circadian rhythmic characteristics and explored the effect of PM2.5 on oscillating clock of lipid function and metabolism in white adipose tissue (WAT) and brown adipose tissue (BAT). C57BL/6 mice were exposed to PM2.5 in a whole-body inhalational exposure system. After 10 weeks, the expression of clock-related genes exhibits more robust CR in BAT than WAT, with the acrophase of PER2 in both types of adipose tissue being significantly decreased at ZT12 and Bmal1 increased at ZT0/24 in WAT in response to PM2.5 exposure. In addition, both CR pattern and expression levels of Sirt1 got significantly inhibited by PM2.5 exposure in WAT, accompanied with adipose dysfunction evidenced by inhibited pattern and expression levels of adipokines at the same ZT time points. Finally, a similar phase right shift from ZT4 to ZT12 in both Sirt3 and Ucp1 in BAT was induced by PM2.5 exposure. These findings indicate that disruption of the CR in adipose tissues could be an important way by which PM2.5 exposure induces metabolic disorder and provide potential targets for further investigation.

5.
Zhen Ci Yan Jiu ; 45(2): 152-6, 2020 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-32144927

RESUMO

OBJECTIVE: To observe the effect contralateral needling of in improving pain, edema and limb dysfunction in stroke patients with shoulder-hand syndrome. METHODS: A total of 62 patients with post-stroke shoulder-hand syndrome were divided into a control group and an observation group, 31 cases in each one. The routine treatment with internal medicine and rehabilitation manipulation was adopted in the two groups. Additionally, the routine acupuncture treatment was used in the control group and the contralateral needling techniques was applied in the observation group. The needles were retained for 30 min. The treatment was given once a day for 5 days a week and consecutively for 4 weeks. Before and after treatment, the score of the modified Fugl-Meyer assessment scale (FMA scale), the score of the visual analogue scale (VAS), the score of the hand edema rating and the score of the modified Barthel index (ADL score) were evaluated. RESULTS: The total effective rate was 90.32% (28/31) in the observation group and was 67.74% (21/31) in the control group. The effective rate in the observation group was higher than that in the control group (P<0.05). VAS score, the score of the hand edema rating, FMA score and ADL score were obviously improved as compared with those before treatment in each group and the scores in the observation group were better than those of the control group (P<0.05). CONCLUSION: The contralateral needling therapy of acupuncture is effective for relieving pain and edema as well as improving the motor function of the affected limb in the patients with post-stroke shoulder-hand syndrome.


Assuntos
Terapia por Acupuntura , Distrofia Simpática Reflexa , Acidente Vascular Cerebral , Pontos de Acupuntura , Humanos , Distrofia Simpática Reflexa/terapia , Resultado do Tratamento
6.
Ecotoxicol Environ Saf ; 194: 110369, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135380

RESUMO

Polysaccharides are the main components of plant cell walls in which they make an important contribution to cadmium (Cd) fixation. However, knowledge regarding the role of root cell wall polysaccharides in Cd accumulation in low-Cd cultivars is limited. Here, we compared the differences in root cell wall polysaccharides between two cultivars of Brassica chinensis L. (pakchoi) with different Cd accumulation abilities. A hydroponic experiment was conducted using low- (Huajun 2) and high-Cd (Hanlv) pakchoi cultivars. We investigated Cd subcellular distribution and Cd accumulation in cell wall polysaccharides and examined polysaccharide modifications in root cell walls by Fourier transform infrared spectroscopy. A Cd adsorption kinetics experiment was conducted to examine the connection between Cd-induced polysaccharide modifications and Cd fixation by cell walls. Amounts of Cd were significantly higher and more Cd was bound to cell walls in the roots of Huajun 2 than in those of Hanlv. These results indicated that the greater Cd retention capacity of the root cell wall in Huajun 2 accounted for the low Cd accumulation in the shoot. Up to 79.4% and 32.1% of cell-wall-bound Cd was found in the pectin and hemicellulose 1, respectively, and higher amounts of Cd were found in these cell wall components of Huajun 2 than in those of Hanlv. Exposure to Cd significantly increased amounts of pectin and hemicellulose 1 in both pakchoi cultivars, but the pectin levels were significantly higher in Huajun 2 than in Hanlv. Huajun 2 had higher pectin methylesterase (PME) activity and a lower degree of pectin methyl-esterification (DM) than Hanlv, although Cd treatments resulted in increased PME activity and decreased DM in both cultivars. The higher Cd treatment (44.5 µM) resulted in enhanced Cd-binding capacity in root cell walls of the two cultivars with higher Cd adsorption levels in the root cell wall of Huajun 2. These results indicate that differences in the amount of cell wall polysaccharide and DM play key roles in establishing the genotypic differences underlying Cd accumulation in pakchoi. These findings conduce to a better understanding of the physiological mechanisms underlying low Cd accumulation in pakchoi and the breeding of new, low-Cd pakchoi cultivars.

7.
Environ Pollut ; 262: 114179, 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32145476

RESUMO

Emerging evidence has shown that exposure to ambient fine particulate matter (PM2.5) is associated with hepatic lipid accumulation. However, the underlying mechanism is not fully characterized yet. Autonomous circadian clock in the liver plays a fundamental role in maintaining lipid metabolism homeostasis. In this study, we evaluated the effects of ambient PM2.5 exposure on the expression of hepatic circadian clock genes and expression rhythm of genes associated with lipid metabolism in mice liver. Male C57BL/6 mice were randomly assigned to ambient PM2.5 or filtered air for 10 weeks via a whole body exposure system. We found that the liver mass was reduced significantly at zeitgeber time (ZT) 8 in mice exposed to PM2.5 but not levels or circadian rhythm of hepatic triglycerides or free fatty acid (FFA). In addition, exposure to PM2.5 led to enhanced expression of bmal1 at ZT0/24, cry1 at ZT16 and rev-erbα at ZT4 and ZT8. Furthermore, the expression of pparα was enhanced in mice liver at ZT4 and ZT8 after PM2.5 exposure, with upregulation of pparα-mediated genes responsible for fatty acid transport and oxidation. Finally, the expression of rate-limiting enzymes for lipid synthesis was all significantly increased in the liver of PM2.5 exposed mice at ZT12. Therefore, the present study provides new perspectives for revealing the etiology of hepatic lipid metabolism abnormality from PM2.5-induced circadian rhythm disorder.

8.
JMIR Mhealth Uhealth ; 8(3): e17776, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32217503

RESUMO

BACKGROUND: Effective treatment of hypertension requires careful self-management. With the ongoing development of mobile technologies and the scarcity of health care resources, mobile health (mHealth)-based self-management has become a useful treatment for hypertension, and its effectiveness has been assessed in many trials. However, there is a paucity of comprehensive summaries of the studies using both qualitative and quantitative methods. OBJECTIVE: This systematic review aimed to measure the effectiveness of mHealth in improving the self-management of hypertension for adults. The outcome measures were blood pressure (BP), BP control, medication adherence, self-management behavior, and costs. METHODS: A systematic search was conducted using 5 electronic databases. The snowballing method was used to scan the reference lists of relevant studies. Only peer-reviewed randomized controlled trials (RCTs) published between January 2010 and September 2019 were included. Data extraction and quality assessment were performed by 3 researchers independently, adhering to the validation guideline and checklist. Both a meta-analysis and a narrative synthesis were carried out. RESULTS: A total of 24 studies with 8933 participants were included. Of these, 23 studies reported the clinical outcome of BP, 12 of these provided systolic blood pressure (SBP) and diastolic blood pressure (DBP) data, and 16 articles focused on change in self-management behavior and medication adherence. All 24 studies were included in the narrative synthesis. According to the meta-analysis, a greater reduction in both SBP and DBP was observed in the mHealth intervention groups compared with control groups, -3.78 mm Hg (P<.001; 95% CI -4.67 to -2.89) and -1.57 mm Hg (P<.001; 95% CI -2.28 to -0.86), respectively. Subgroup analyses showed consistent reductions in SBP and DBP across different frequencies of reminders, interactive patterns, intervention functions, and study duration subgroups. A total of 16 studies reported better medication adherence and behavioral change in the intervention groups, while 8 showed no significant change. Six studies included an economic evaluation, which drew inconsistent conclusions. However, potentially long-term financial benefits were mentioned in all economic evaluations. All studies were assessed to be at high risk of bias. CONCLUSIONS: This review found that mHealth self-management interventions were effective in BP control. The outcomes of this review showed improvements in self-management behavior and medication adherence. The most successful mHealth intervention combined the feature of tailored messages, interactive communication, and multifaceted functions. Further research with longer duration and cultural adaptation is necessary. With increasing disease burden from hypertension globally, mHealth offers a potentially effective method for self-management and control of BP. mHealth can be easily integrated into existing health care systems. TRIAL REGISTRATION: PROSPERO CRD42019152062; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=152062.

9.
Eur Radiol ; 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32144457

RESUMO

OBJECTIVE: To explore whether sex-specific abdominal visceral fat composition on CT can predict the Fuhrman nuclear grade of clear cell renal cell carcinoma (ccRCC). METHODS: One hundred seventy-one patients (123 males and 48 females) from four hospitals (multicentre group) and 159 patients (109 males and 50 females) from the cancer imaging archive (TCIA-KIRC group) with pathologically proven ccRCC (multicentre: 124 low grade and 47 high grade; TCIA-KIRC: 79 low grade and 80 high grade) were retrospectively included. Abdominal fat was segmented into subcutaneous fat area (SFA) and visceral fat area (VFA) on CT using ImageJ. The total fat area (TFA) and relative VFA (rVFA) were then calculated. Clinical characteristics (age, sex, waist circumference and maximum tumour diameter) were also assessed. Univariate and multivariate logistic regression analyses were performed to identify the association between general or sex-specific visceral fat composition and Fuhrman grade. RESULTS: Females with high-grade ccRCC from the multicentre group had a higher rVFA (42.4 vs 31.3, p = 0.001) than those with low-grade ccRCC after adjusting for age. There was no significant difference in males. The rVFA remained a stable and independent predictor for females high-grade ccRCC in both the univariate (multicentre: OR 1.205, 95% CI 1.074-1.352, p = 0.001; TCIA-KIRC: OR 1.171, 95% CI 1.016-1.349, p = 0.029) and multivariate (multicentre: OR 1.095, 95% CI 1.024-1.170, p = 0.003; TCIA-KIRC: OR 1.103, 95% CI 1.024-1.187, p = 0.010) models. CONCLUSIONS: Sex-specific visceral fat composition has different values for predicting high-grade ccRCC and could be used as an independent predictor for females with high-grade ccRCC. KEY POINTS: • Visceral fat measurement (rVFA) as an independent predictor for high-grade ccRCC had good predictive power in females, but not in males. • Sex-specific visceral fat composition was significantly associated with high-grade ccRCC in females only. • The rVFA could be considered one of the risk factors for high-grade ccRCC for females.

10.
Front Immunol ; 11: 82, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117244

RESUMO

B-1a cells produce "natural" antibodies (Abs) to neutralize pathogens and clear neo self-antigens, but the fundamental selection mechanisms that shape their polyreactive repertoires are poorly understood. Here, we identified a B cell progenitor subset defined by Fc receptor-like 6 (FCRL6) expression, harboring innate-like defense, migration, and differentiation properties conducive for natural Ab generation. Compared to FCRL6- pro B cells, the repressed mitotic, DNA damage repair, and signaling activity of FCRL6+ progenitors, yielded VH repertoires with biased distal Ighv segment accessibility, constrained diversity, and hydrophobic and charged CDR-H3 sequences. Beyond nascent autoreactivity, VH11 productivity, which predominates phosphatidylcholine-specific B-1a B cell receptors (BCRs), was higher for FCRL6+ cells as was pre-BCR formation, which was required for Myc induction and VH11, but not VH12, B-1a development. Thus, FCRL6 revealed unexpected heterogeneity in the developmental origins, regulation, and selection of natural Abs at the pre-BCR checkpoint with implications for autoimmunity and lymphoproliferative disorders.

11.
Plant J ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32130751

RESUMO

Circadian organ movements are ubiquitous in plants. These rhythmic outputs are thought to be regulated by the circadian clock and auxin signaling, but the underlying mechanisms have not been clarified. Flowers of Nicotiana attenuata change their orientation during the daytime through a 140° arc to balance needs for pollinators and the protection of their reproductive organs. This rhythmic trait is under the control of the circadian clock and results from the bending and re-straightening movements of the pedicel, stems that connect flowers to the inflorescence. Using an explant system that allowed pedicel growth and curvature responses to be characterized with high spatial and temporal resolution, we demonstrate that this movement is organ-autonomous and mediated by auxin. Changes in the growth curvature of the pedicel are accompanied by an auxin gradient and dorsiventral asymmetry in auxin-dependent transcriptional responses, and applications of auxin transport inhibitors influence the normal movements of this organ. Silencing the expression of the circadian clock component ZEITLUPE (ZTL) arrests changes in the growth curvature of the pedicel and alters auxin signaling and responses. IAA19-like, an Aux/IAA transcriptional repressor that is circadian-regulated and differentially expressed between opposite tissues of the pedicel, and therefore possibly involved in the regulation of changes in organ curvature, physically interacts with ZTL. Together these results are consistent with a direct link between the circadian clock and the auxin signaling pathway in the regulation of this rhythmic floral movement.

12.
J Org Chem ; 85(5): 3568-3575, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041407

RESUMO

Two novel heterowheel [4]pseudorotaxanes consisting of cucurbit[7]uril (Q[7]) and symmetrical-tetramethyl-cucurbit[6]uril (TMeQ[6]) were constructed via the multirecognition mechanism, in which Q[7] can rotate freely around the horizontal axis, while TMeQ[6] cannot. In the construction process, due to strong repulsive forces between carbonyl portals of two neighboring wheels, the dethreading and movement of the wheels along the axle was observed. The dissociation of the [4]pseudorotaxanes was also discussed.

13.
Fish Shellfish Immunol ; 99: 301-309, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32061873

RESUMO

Matrix metalloproteinases (MMPs) are a cluster of enzymes that degrade the extracellular matrix (ECM) and some intracellular proteins; as such, they play an important role in tissue regeneration, infant growth, animal reproduction, and immunity. Most research into MMPs focuses mainly on their effects on the mammalian immune system. However, it is not clear how MMPs affect immune processes in crustaceans. Here, we cloned the open reading frame (ORF) of Eriocheir sinensis (Chinese mitten crab) MMP-14 (EsMMP-14) to explore the role of MMPs in crustacean innate immune responses. RT-PCR results showed that stimulation of crab with LPS and poly I:C upregulated expression of EsMMP-14 markedly. Besides, following the stimulation of 20-Hydroxyecdysone, the expression level of EsMMP-14 increased robustly, suggesting that EsMMP-14 involved in the molt process of E. sinensis. Hematoxylin and eosin staining of hepatopancreas and intestine revealed that knocking down EsMMP-14 maintained morphology following infection by Bacillus thuringiensis. Moreover, downregulated expression of EsMMP-14 increased the survival rate of infected E. sinensis. These results show that EsMMP-14 plays a role in innate immune responses of E. sinensis and fills a gap in our knowledge about the function of MMPs in crustaceans.

14.
Bioresour Technol ; 304: 122928, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32106020

RESUMO

In order to explore changes in microbial enzyme activity and bacterial community, a 60-day composting experiment was conducted using cattle manure and straw under aeration rates of 0.45, 0.68, and 0.90 L min-1 kg-1 fresh weight. High aeration rate increased the cellulase, urease, alkaline and acid phosphatase activities, but decreased that of invertase and catalase. Cellulase, alkaline phosphatase and catalase were the main enzymes that affected the composting process. Microbial analysis showed that high aeration rate increased the uniformity of bacterial community in thermophilic phase, but decreased that in mature phase. Different aeration rate affected the bacterial community structure and further influenced the relationship between enzyme and functional bacteria. Regulating the temperature, moisture content and EC in specific phases to affect bacterial community succession could provide guidance for improving maturity of composting.


Assuntos
Celulase , Compostagem , Animais , Bactérias , Bovinos , Esterco , Solo , Temperatura Ambiente
15.
J Clin Densitom ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-32037205

RESUMO

This 2-year longitudinal study aimed to detect the associations of sex steroids, sex hormone-binding globulin with bone parameters and the changes thereof in Chinese male adolescents. A total of 642 male students aged 12-16 years from a secondary school in Jiangmen, China, were included. Total testosterone (T), total oestradiol (E2), and sex hormone-binding globulin were measured by chemiluminescence immunoassay. The bioavailable T (BioT) and E2 (BioE2) were calculated. The speed of sound, broadband ultrasound attenuation, and stiffness index of the right heel were measured by Sahara Clinical Bone Sonometer at both baseline and 2-year follow-up. The confounding effects of age, height, weight, pubertal stage, physical activity, energy-adjusted dietary calcium intake, and dietary vitamin D intake were adjusted. The baseline value of each bone parameter was also adjusted in the longitudinal analysis. Results showed that total T and BioT were positively associated with bone parameters and changes in them (ß = 0.076-0.115, p < 0.05). A threshold effect of BioT on broadband ultrasound attenuation, stiffness index and their changes were also observed. Positive associations between BioT and bone mass gain were observed only in individuals with BioT levels <240.0 ng/dl (ß = 0.088-0.131, p < 0.05). Moreover, total E2 or BioE2 were found to be inversely associated with speed of sound and its change (ß = -0.109 to -0.077, p < 0.05). This study supported that in Chinese male adolescents, serum T was a positive predictor for bone formation with a threshold effect, and E2 could have influence on the changes in bone architecture during puberty. These findings may improve the understanding of the effects of sex steroids on the acceleration of bone formation in male adolescents and provide useful information for the prediction model establishment of peak bone mass.

16.
Environ Pollut ; 260: 113984, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32041019

RESUMO

1-nitropyrene (1-NP) is a key component of diesel exhaust-sourced fine particulate matter (PM2.5). Our recent study demonstrated that gestational 1-NP exposure caused placental proliferation inhibition and fetal intrauterine growth restriction (IUGR). This study aimed to investigate the role of genotoxic stress on 1-NP-induced placental proliferation inhibition and fetal IUGR. Human trophoblasts were exposed to 1-NP (10 µM). Growth index was reduced and PCNA was downregulated in 1-NP-exposed placental trophoblasts. More than 90% of 1-NP-exposed trophoblasts were arrested in either G0/G1 or G2/M phases. CDK1 and cyclin B, two G2/M cycle-related proteins, and CDK2, a G0/G1 cycle-related protein, were reduced in 1-NP-exposed trophoblasts. Phosphorylated Rb, a downstream molecule of CDK2, was inhibited in 1-NP-exposed trophoblasts. Moreover, DNA double-strand break was observed and γ-H2AX, another indicator of DNA double-strand break, was upregulated in 1-NP-exposed trophoblasts. Phosphorylated ATM, a key molecule of genotoxic stress, and its downstream molecule Chk2 were elevated. By contrast, Cdc25A, a downstream target of Chk2, was reduced in 1-NP-exposed trophoblasts. Phenyl-N-t-butylnitrone (PBN), a free radical scavenger, inhibited 1-NP-induced genotoxic stress and trophoblast cycle arrest. Animal experiment showed that N-acetylcysteine (NAC), an antioxidant, rescued 1-NP-induced placental proliferation inhibition and fetal IUGR in mice. These results provide evidence that reactive oxygen species (ROS)-mediated cellular genotoxic stress partially contributes to 1-NP-induced placental proliferation inhibition and fetal IUGR.

17.
Nano Lett ; 20(2): 1468-1474, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32004007

RESUMO

We report how the direction of quantum dot (QD) lasing can be engineered by exploiting high-symmetry points in plasmonic nanoparticle (NP) lattices. The nanolaser architecture consists of CdSe-CdS core-shell QD layers conformally coated on two-dimensional square arrays of Ag NPs. Using waveguide-surface lattice resonances (W-SLRs) near the Δ point in the Brillouin zone as optical feedback, we achieved lasing from the gain in CdS shells at off-normal emission angles. Changing the periodicity of the plasmonic lattices enables other high-symmetry points (Γ or M) of the lattice to overlap with the QD shell emission, which facilitates tuning of the lasing direction. We also increased the thickness of the QD layer to introduce higher-order W-SLR modes with additional avoided crossings in the band structure, which expands the selection of cavity modes for any desired lasing emission angle.

18.
ACS Nano ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049478

RESUMO

The tailored spatial polarization of coherent light beams is important for applications ranging from microscopy to biophysics to quantum optics. Miniaturized light sources are needed for integrated, on-chip photonic devices with desired vector beams; however, this issue is unresolved because most lasers rely on bulky optical elements to achieve such polarization control. Here, we report on quantum dot-plasmon lasers with engineered polarization patterns controllable by near-field coupling of colloidal quantum dots to metal nanoparticles. Conformal coating of CdSe-CdS core-shell quantum dot films on Ag nanoparticle lattices enables the formation of hybrid waveguide-surface lattice resonance (W-SLR) modes. The sidebands of these hybrid modes at nonzero wavevectors facilitate directional lasing emission with either radial or azimuthal polarization depending on the thickness of the quantum dot film.

19.
Cell Death Dis ; 11(1): 15, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907356

RESUMO

Oral lichen planus (OLP) is a kind of oral epithelial disorder featured with keratinocyte apoptosis and inflammatory reaction. The pathogenesis of OLP remains an enigma. Herein, we showed that the levels of miR-26a/b were robustly down-regulated in oral mucosal biopsies, serum and saliva in OLP patients compared with healthy control. Moreover, we found the binding sites of vitamin D receptor (VDR) in the promoter regions of miR-26a/b genes and proved that the induction of miR-26a/b was VDR dependent. The reduction of miR-26a/b expression was also detected in the oral epithelium of vitamin D deficient or VDR knockout mice. miR-26a/b inhibitors enhanced apoptosis and Type 1T helper (Th1) cells-related cytokines production in oral keratinocytes, whereas miR-26a/b mimics were protective. Mechanistically, we analyzed miRNA target genes and confirmed that miR-26a/b blocked apoptosis by directly targeting Protein Kinase C δ (PKCδ) which promotes cellular apoptotic processes. Meanwhile, miR-26a/b suppressed Th1-related cytokines secretion through targeting cluster of the differentiation 38 (CD38). In accordant with miR-26a/b decreases, PKCδ and CD38 levels were highly elevated in OLP patients' samples. Taken together, our present investigations suggest that vitamin D/VDR-induced miR-26a/b take protective functions in OLP via both inhibiting apoptosis and impeding inflammatory response in oral keratinocytes.

20.
Ann Hum Genet ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31960406

RESUMO

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver diseases. However, the pathogenesis of NAFLD is largely unknown. Here, we investigated the specific role of miR-499-5p in NAFLD. METHODS: Free fatty acid was used to induce HL-7702 cell line to establish a NAFLD cell model, and animal models of NAFLD were constructed by feeding C57BL/6 mice with a high-fat diet. Expression levels of miR-499-5p in the HL-7702 cells and C57BL/6 mice were determined by quantitative real-time polymerase chain reaction. In addition, functional experiments were carried out through transfecting miR-499-5p inhibitor into NAFLD cells, and injecting NAFLD mice with a lentiviral vector with the miR-499-5p inhibitor. Furthermore, the effects of miR-499-5p on lipidation and inflammation were investigated by oil red O staining, hematoxylin-eosin staining, and biochemical analysis. RESULTS: Compared with normal controls, the expression of miR-499-5p was significantly up-regulated in NAFLD cells and tissues in mouse. After NAFLD cells transfected by miR-499-5p inhibitor, the expression of miR-499-5p was inhibited, the lipid deposition and content of triglycerides (TGs) were reduced, and the lipidation was improved. Simultaneously, after NAFLD mice were injected with the miR-499-5p lentiviral vector, the degree of lipid droplet deposition and content of TGs were also reduced. In addition, it decreased the levels of total cholesterol and aspartate aminotransferase in serum, and improved hepatic lipid metabolism. CONCLUSIONS: Inhibition of miR-499-5p expression improved NAFLD in mice, which provided a new direction for the treatment of NAFLD.

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