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1.
Mater Sci Eng C Mater Biol Appl ; 106: 110277, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753341

RESUMO

The self-growth and self-strengthening of natural biomaterials provided us strategies for new materials design. In this paper, the microstructure and fracture mechanisms of the wild wolf tusk's enamel were studied. The enamel included four-order hierarchies, which were the hydroxyapatite (HAP) fiber (first-order, nano-scale, ploy-crystals), enamel rod (second-order, micro-scale, rope-like), enamel type (third-order, meso-scale, mat-like) and the enamel patterns (forth-order, macro-scale), respectively. It was interesting to find that the numerous nano-grains distributed disorderly in a single HAP fiber. The thousands HAP fibers bundled together to form the rope-like enamel rod. The protein ligaments were discovered between adjacent enamel rods. The out enamel, inner enamel and P&D-zones showed a criss-cross type and ran through whole enamel pattern in three-dimensional space. The enamel of the wild wolf tusk exhibited an excellent fracture toughness based on the nanoindentation tests. The fracture morphology in transverse direction indicated that the cracks preferred to propagate along the weak interface (protein or interrod) and cut those enamel rods perpendicular to the propagation direction. However, the cracks extended obviously forward along the step-like paths from the outmost surface of the enamel to the enamel-dentin junction in the longitudinal direction. It was considered that the protein ligament was the main reason for the good fracture toughness of the bulk enamel. Our studies reveal that the design strategies of the natural material can be applied to guide the development of high-performance artificial materials.

2.
Neuroreport ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31688420

RESUMO

Hyperactivity of the hypothalamic-pituitary-adrenal axis and impairment of the central corticotropin-releasing factor system are factors in the pathogenesis of depression. Though several antagonists of the corticotropin-releasing factor 1 receptor were effective in the recognized behavioral tests for antidepressant activity, there is still little information on the potential interactions between corticotropin-releasing factor 1 receptor inhibitors and conventional antidepressant therapy. The aim of our study was to assess the influence of CP154526, a corticotropin-releasing factor 1 receptor blocker, which presented some signs of depression. Our results revealed that CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment notably improved the sucrose consumption, produced anti-depressive-like behavior in open-field test, as well as immobility time in forced swimming test. The levels of interleukin-6, interleukin-1ß, tumor necrosis factor-α, and corticotropin-releasing hormone concentration in the serum were inhibited effectively by CP154526 or fluoxetine administration. Real-time quantitative PCR and western blot analysis showed the upregulated levels of brain-derived neurotrophic factor and growth associated protein 43 (GAP43) in the hypothalamus of the rats exposed to chronic unpredictable mild stress (CUMS), while different degrees of downregulation in their expression were detected after CP154526 (5 and 10 mg/kg) or fluoxetine (10 mg/kg) treatment, respectively. Thus, our data demonstrated that CP154526 exhibited antidepressant effect in CUMS rats, which might be mediated by decreasing the brain-derived neurotrophic factor and GAP43 expression in the hypothalamus.

3.
Nat Nanotechnol ; 14(11): 1048-1055, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31686005

RESUMO

Many living organisms track light sources and halt their movement when alignment is achieved. This phenomenon, known as phototropism, occurs, for example, when plants self-orient to face the sun throughout the day. Although many artificial smart materials exhibit non-directional, nastic behaviour in response to an external stimulus, no synthetic material can intrinsically detect and accurately track the direction of the stimulus, that is, exhibit tropistic behaviour. Here we report an artificial phototropic system based on nanostructured stimuli-responsive polymers that can aim and align to the incident light direction in the three-dimensions over a broad temperature range. Such adaptive reconfiguration is realized through a built-in feedback loop rooted in the photothermal and mechanical properties of the material. This system is termed a sunflower-like biomimetic omnidirectional tracker (SunBOT). We show that an array of SunBOTs can, in principle, be used in solar vapour generation devices, as it achieves up to a 400% solar energy-harvesting enhancement over non-tropistic materials at oblique illumination angles. The principle behind our SunBOTs is universal and can be extended to many responsive materials and a broad range of stimuli.

4.
J Cell Physiol ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691285

RESUMO

Nerve damage can lead to movement and sensory dysfunction, with high morbidity and disability rates causing severe burdens on patients, families, and society. DNA methylation is a kind of epigenetics, and a great number of previous studies have demonstrated that DNA methylation plays an important role in the process of nerve regeneration and remodeling. However, compared with the central nervous system, the peripheral nervous system shows stronger recovery after injury, which is related to the complex microenvironment and epigenetic changes occurring at the site of injury. Therefore, what common epigenetic changes between the central and peripheral nervous systems remain to be elucidated. We first screened differential methylation genes after spinal cord injury and sciatic nerve injury using whole-genome bisulfite sequencing and methylated DNA immunoprecipitation sequencing, respectively. Subsequently, a total of 16 genes had the same epigenetic changes after spinal cord injury and sciatic nerve injury. The Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed to identify the critical biological processes and pathways. Furthermore, a protein-protein interaction network analysis indicated that Dnm3, Ntrk3, Smurf1, Dpysl2, Kalrn, Shank1, Dlg2, Arsb, Reln, Bmp5, Numbl, Prickle2, Map6, and Htr7 were the core genes. These outcomes may provide novel insights into the molecular mechanism of the subacute phase of nerve injury. These verified genes can offer potential diagnostic and therapeutic targets for nerve injury.

5.
J Viral Hepat ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31755220

RESUMO

Antiviral therapy has been shown to improve the prognosis of hepatitis B virus (HBV) DNA-positive hepatocellular carcinoma (HCC) after radical treatment, but antiviral treatments require further optimization. This study aimed to evaluate the efficacies of different antiviral strategies with HCC patients after hepatectomy/ablation. This prospective, randomized, controlled, and multi-center trial enrolled HBV DNA-positive primary HCC patients after hepatectomy/ablation between January 2007 and January 2009. Patients were divided into four groups: early-combination (entecavir plus Peg-interferon [IFN]α-2a co-administration during year 1); late-combination (addition of Peg-IFNα-2a for 48 weeks after 1 year of entecavir); nucleos(t)ide analogue[NA] monotherapy; and non-antiviral treatment. Primary endpoints included recurrence-free survival and overall survival. A total of 447 patients were enrolled. The 2-year and 8-year recurrence free survival and 8-year overall survival rates were significantly higher in the early-combination group than in the other two antiviral groups (P<0.05). After 48 weeks treatment, more patients achieved an HBsAg reduction >1500 IU/ml and the mean HBsAg level was significantly lower in the early-combination group compared with the late-combination and NA monotherapy groups (P<0.05). Multivariate analysis showed that early-combination therapy and a reduction in HBsAg by >1500 IU/mL after 48 weeks of therapy correlated with reduced mortality and disease recurrence. Early introduction of combination antiviral treatment may represent a more effective therapeutic strategy for patients with HBV DNA-positive HCC after hepatectomy/ablation. A reduction in HBsAg by >1500 IU/mL after 48 weeks treatment is associated with reduced mortality and disease recurrence of HBV DNA-positive HCC patients after hepatectomy/ablation.

6.
Environ Sci Technol ; 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31713416

RESUMO

Hydrogen production using two-chamber microbial electrolysis cells (MECs) is usually adversely impacted by a rapid rise in catholyte pH because of proton consumption for the hydrogen evolution reaction. While using a bipolar membrane (BPM) will maintain a more constant electrolyte pH, the large voltage loss across this membrane reduces performance. To overcome these limitations, we used an acidic catholyte to compensate for the potential loss incurred by using a BPM. A hydrogen production rate of 1.2 ± 0.7 L-H2/L/d (jmax = 10 ± 0.4 A/m2) was obtained using a Pt cathode and BPM with a pH difference (ΔpH = 6.1) between the two chambers. This production rate was 2.8 times greater than that of a conventional MEC with an anion exchange membrane (AEM, 0.43 ± 0.1 L-H2/L/d, jmax = 6.5 ± 0.3 A/m2). The catholyte pH gradually increased to 11 ± 0.3 over 9 days using the BPM and Pt/C, which decreased current production (jmax = 2.5 ± 0.3 A/m2). However, this performance was much better than that obtained using an AEM as the catholyte pH increased to 10 ± 0.4 after just one day. The use of an activated carbon cathode with the BPM enabled stable performance over a longer period of 12 days, although it reduced the hydrogen production rate (0.45 ± 0.1 L-H2/L/d).

7.
8.
EBioMedicine ; 49: 157-171, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31678002

RESUMO

BACKGROUND: Liver is one of the most preferred destinations of distant metastasis in gastric cancer (GC). As effective treatment is still limited, the prognosis of GC patients bearing liver metastasis is poor. We filter out lysyl oxidase (LOX) to study its function in the tumor microenvironment (TME) and seek for potential therapeutic targets. METHODS: Transcription analysis on 6 cases of liver metastasis of GC patients with respective paired primary tumors and adjacent normal livers was performed. The filtration out of LOX was done using 5 datasets. 69 GC liver metastasis tissues were utilized to perform immunohistochemistry (IHC) and analyze prognosis. Computed Tomography (CT) combined 3D organ reconstruction bioluminescence imaging was performed to precisely evaluate the metastatic tumor burden on liver of intrasplenic injection mouse model. Human and mouse cancer associated fibroblasts (CAFs) in liver metastasis were separated to culture to study the interaction of LOX and TGF-ß1. Patients-derived xenograft (PDX) model was established using liver metastasis of patients to evaluate the therapeutic value of LOX inhibitor ß-aminopropionitrile (BAPN). RESULTS: CAFs-derived LOX at liver metastatic niche of GC promotes niche formation and outgrowth thus predicts poor prognosis. Meanwhile tumor cells in niche secrete TGF-ß1 to nourish CAFs and stimulate them to produce more LOX in turn. The mechanism involved in LOX-mediated proliferation facilitation is enhancement of Warburg effect. The inhibitor of LOX, BPAN could hamper the effect brought by LOX in vivo and in vitro. INTERPRETATION: Our study has unveiled a positive feedback loop between CAFs and tumor cells in liver metastasis niche of GC. The core molecule is LOX which facilitates Warburg effect. Targeting LOX with its inhibitor BAPN might serve as a potential therapeutic strategy. FUND: This research was supported by the National Natural Science Foundation of China (31872740), the 100-member plan of the Shanghai Municipal Commission of Health and Family Planning (2017BR043), Shanghai Science and Technology Commission Project(17ZR1416800), Renji Hospital Training Fund (PYMDT-003, PYIII-17-015), National Natural Science Foundation of China (81672358), the Shanghai Municipal Education Commission-Gao feng Clinical MedicineGrant Support (20181708), Program of Shanghai Academic/Technology Research Leader(19XD1403400), Science and Technology Commission of Shanghai Municipality (18410721000), Shanghai Municipal Health Bureau (2018BR32), China Postdoctoral Science Foundation (2018M640403), National Natural Science Foundation of China (81701945) and Youth project of Shanghai Municipal Health Commission(20164Y0045).

9.
Bioresour Technol ; : 122410, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31757616

RESUMO

The aim of this work was to investigate how the initial C/N ratio during composting of chicken manure/corn stover mix affected the succession of dominant bacteria in the mix which led to the reduction of the total losses of N and C in the composting process. 16S rDNA sequencing indicated that the succession of predominant bacteria was significantly affected by the temperature and the initial C/N ratio during composting. Redundancy analysis showed that higher C/N appeared to promote the relative abundance of nitrogen fixing bacteria Thermoactinomyces, Planifilum, Flavobacterium, Bacillaceae, Pseudomonas,Sphingobacterium, Paenibacillus, Bacillus and Thermobifida, while compressing the denitrifying bacteria Pusillimonas, Ignatzschineria, Alcanivorax, Cerasibacillus, Truepera and Erysipelothrix. C/N ratio of 30:1 yielded the least C/N losses in the composting process, indicating that adjustment to the initial C/N ratio could affect nitrogen transforming bacteria to reduce the total losses of N and C and improve compost quality.

10.
Yi Chuan ; 41(11): 1050-1059, 2019 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-31735707

RESUMO

High oleic (HO) peanut (Arachishypogaea L.) oils benefit human health and industrial production due to its superior nutritional composition and thermo-oxidative stability. However, HO peanut is sensitive to cold stress especially during germination, which limits its distribution in low temperature areas. To understand the molecular mechanism of cold responses in HO peanuts at germination stage, four HO peanut varieties with different cold tolerance were selected in field experiments to analyze their genome-wide gene regulation under low temperatures. High-throughput sequencing and transcriptome analysis revealed a total of 139 429 unigenes. Among these, 3520 common differentially expressed genes (DEG) were detected between two groups of cold-tolerant and cold-sensitive peanuts, and the number of up-regulated genes was greater than that of down-regulated genes in the cold-tolerant peanuts. Gene ontology analysis indicates that the number of DEGs involved in cell membrane metabolism and integrity as well as proteins located in the cell periphery were significantly higher in the cold-tolerant peanuts. KEGG pathway analysis suggests that plant-pathogen interaction and plant hormone signal transduction pathway play important roles in cold tolerance. Four cold-induced genes, TIC(TIME FOR COFFEE), ATX3(histone-lysine N-methyltransferase ATX3-like), AGO4(argonaute 4-like), FER(FERONIA-like receptor protein kinase), and three transcription factor genes, bHLH(bHLH49-like transcription factor), MYB(MYB-related protein 3R-1-like)and EREB(Ethylene-responsive element binding factor 6)were selected to verify the expression profile via real-time quantitative PCR detection. The expression of TIC, ATX3, AGO4, bHLH, MYB and EREB significantly increased within 3 hours after low temperature stress, while the expression of FER significantlyincreased after 12 hours, suggesting that these genes responded to low temperature stress during peanut germination. This work not only sheds light on the transcriptional regulation of HO peanut under low-temperature stress during germination but also provides data resources for screening candidate genes in improving peanuts stress resistance.


Assuntos
Arachis/genética , Temperatura Baixa , Germinação , Transcriptoma , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico
11.
Gigascience ; 8(11)2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31742599

RESUMO

BACKGROUND: Measurement of plant traits with precision and speed on large populations has emerged as a critical bottleneck in connecting genotype to phenotype in genetics and breeding. This bottleneck limits advancements in understanding plant genomes and the development of improved, high-yielding crop varieties. RESULTS: Here we demonstrate the application of deep learning on proximal imaging from a mobile field vehicle to directly estimate plant morphology and developmental stages in wheat under field conditions. We developed and trained a convolutional neural network with image datasets labeled from expert visual scores and used this "breeder-trained" network to classify wheat morphology and developmental stages. For both morphological (awned) and phenological (flowering time) traits, we demonstrate high heritability and very high accuracy against the "ground-truth" values from visual scoring. Using the traits predicted by the network, we tested genotype-to-phenotype association using the deep learning phenotypes and uncovered novel epistatic interactions for flowering time. Enabled by the time-series high-throughput phenotyping, we describe a new phenotype as the rate of flowering and show heritable genetic control for this trait. CONCLUSIONS: We demonstrated a field-based high-throughput phenotyping approach using deep learning that can directly measure morphological and developmental phenotypes in genetic populations from field-based imaging. The deep learning approach presented here gives a conceptual advancement in high-throughput plant phenotyping because it can potentially estimate any trait in any plant species for which the combination of breeder scores and high-resolution images can be obtained, capturing the expert knowledge from breeders, geneticists, pathologists, and physiologists to train the networks.

12.
Sci Total Environ ; : 135475, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31767296

RESUMO

Ectomycorrhizal (ECM) fungi are closely related to vegetation compositions, edaphic properties, and site-specific processes. However, the coevolutionary mechanisms underlying the spatial distributions in floristic and ECM fungal composition in the context of biotic adaptations and abiotic variances remain unclear. We combine a total of 25 ECM fungus-associated environmental variables to impose three types of composite scores and then quantify the environmental gradients of geographical site, soil chemical property and vegetation functional trait across 122 grids of 20 m × 20 m in a 25-hm2 forest plot. Significant dissimilarities in vegetational and ECM fungal abundance and composition existed along the above environmental gradients. Specifically, a contrasting floristic distribution (e.g., Betula platyphylla vs. Tilia mandshurica) existed between the northeastern and southwestern areas and was closely related to the nutrient and moisture gradients (with high levels in the west and low levels in the east). Furthermore, the ECM fungal communities were more abundant in the nutrient-poor and low-moisture environments than in the nutrient-rich and high-moisture environments, and the mixed-forest in the middle-gradient sites between the northeastern and southwestern areas harbored the highest ECM fungal diversity. These findings suggest that predictable within-site vegetation succession is closely related to ECM-associated determinants and the natural spatial heterogeneity of edaphic properties at a local scale.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31767359

RESUMO

OBJECTIVE: To investigate a technical method for harvesting and using the descending branch of the lateral circumflex femoral artery (DLCFA) in coronary artery bypass grafting (CABG). METHODS: Between January 2017 and January 2019, 40 patients (36 in the planed selection group and 4 in the temporary decision group) with mean age of 49.1 ± 7.5 years received DLCFA as an arterial conduit in CABG. In all patients, the DLCFA was successfully harvested via an anterior thigh incision. Depending on the location of the target vessel, the DLCFA was used as a free graft or a composite graft. RESULTS: Of the 44 patients in the planned selection group, DLCFA harvesting was abandoned in 8 patients because computed tomographic angiography revealed anatomical variation or stenosis of the superficial femoral artery. Of the 5 patients in the temporary decision group, harvesting was abandoned in 1 because of short length and thin caliber. On an average, 3.7 ± 0.9 distal anastomoses were created during CABG, with no adverse effects. The length of the harvested DLCFA was 9.9 ± 1.7 cm, with an average proximal lumen diameter of 3.4 ± 0.7 mm. The DLCFA was used as a free graft in 26 patients and as a "Y"-shape composite graft in 14 patients. Total arterial CABG was performed in 75% of the patients. CONCLUSIONS: The DLCFA is an alternative conduit for CABG. It can be harvested easily and safely. However, preoperative computed tomographic angiography examination is necessary for the smooth application of the DLCFA, and an appropriate strategy for graft establishment should be considered.

14.
Ground Water ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31667828

RESUMO

Streamline simulation in groundwater flow modeling is a time-consuming process when a large number of streamlines are analyzed. We develop a parallelization method on graphics processing units (GPUs) for the semi-analytical particle tracking algorithm developed by Pollock (1988). Compute Unified Device Architecture was used to implement the parallel method. Forward and backward tracking of a streamline is handled by an individual thread. A GPU includes a grid of blocks where a block handles 32 threads. We use multi-GPUs to accelerate streamline tracking in a flow model with millions of particles. The method was examined to simulate streamlines for identifying three-dimensional (3D) flow systems in a Tóthian basin. The speedup exceeds 1000 when 8 NVIDIA GPUs are used to simulate 5 million or more streamlines.

15.
Cell Prolif ; : e12730, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746040

RESUMO

OBJECTIVES: In peripheral neuropathy, the underlying mechanisms of nerve and muscle degeneration include chronic inflammation and oxidative stress in fibrotic tissues. (-)-Epigallocatechin gallate (EGCG) is a major, active component in green tea and may scavenge free radical oxygen and attenuate inflammation. Conservative treatments such as steroid injection only deal with early, asymptomatic, peripheral neuropathy. In contrast, neurolysis and nerve conduit implantation work effectively for treating advanced stages. MATERIALS AND METHODS: An EGCG-loaded polycaprolactone (PCL) porous scaffold was fabricated using an integrated moulding method. We evaluated proliferative, oxidative and inflammatory activity of rat Schwann cells (RSCs) and rat skeletal muscle cells (RSMCs) cultured on different scaffolds in vitro. In a rat radiation injury model, we assessed the morphological, electrophysiological and functional performance of regenerated sciatic nerves and gastrocnemius muscles, as well as oxidative stress and inflammation state. RESULTS: RSCs and RSMCs exhibited higher proliferative, anti-oxidant and anti-inflammatory states in an EGCG/PCL scaffold. In vivo studies showed improved nerve and muscle recovery in the EGCG/PCL group, with increased nerve myelination and muscle fibre proliferation and reduced macrophage infiltration, lipid peroxidation, inflammation and oxidative stress indicators. CONCLUSIONS: The EGCG-modified PCL porous nerve scaffold alleviates cellular oxidative stress and repairs peripheral nerve and muscle structure in rats. It attenuates oxidative stress and inflammation in vivo and may provide further insights into peripheral nerve repair in the future.

16.
Drug Deliv ; 26(1): 1206-1221, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31746243

RESUMO

As an emerging novel drug carrier, nanoparticles provide a promising way for effective treatment of parasitic diseases by overcoming the shortcomings of low bioavailability, poor cellular permeability, nonspecific distribution and rapid elimination of antiparasitic drugs from the body. In recent years, some kinds of ideal nanocarriers have been developed for antiparasitic drug delivery. In this review, the progress of the enhanced antiparasitic effects of different nanoparticles payload and their influencing factors were firstly summarized. Secondly, the transport and disposition process in the body were reviewed. Finally, the challenges and prospects of nanoparticles for antiparasitic drug delivery were proposed. This review will help scholars to understand the development trend of nanoparticles in the treatment of parasitic diseases and explore strategies in the development of more efficient nanocarriers to overcome the difficulty in the treatment of parasite infections in the future.

17.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(5): 485-489, 2019 Oct 01.
Artigo em Chinês | MEDLINE | ID: mdl-31721494

RESUMO

OBJECTIVE: To explore the mechanism of smoking that promotes chronic periodontitis from the perspective of gingival microcirculation. METHODS: In experiment one, upper anterior teeth (n=102) from smokers with chronic periodontitis (Group A), nonsmokers with chronic periodontitis (Group B), and nonsmokers with healthy periodontal conditions (Group C) were selected to undergo gingival blood flow (GBF) through laser doppler flowmetry. In experiment two, the tissues obtained from gums during periodontal flap surgery were divided into smoking (Group A') and nonsmoking (Group B') groups, and the gingival tissue obtained from periodontal healthy nonsmokers treated with crown lengthening surgery or impacted wisdom tooth extraction served as the control group (Group C'). The microvessels density (MVD) of the gingival tissue from the three groups was determined in the tissue sections. SPSS 22.0 was used for statistical analysis. RESULTS: Compared with group C, GBF of all teeth increased in group B, and there were significant differences among 12, 21 and 23 teeth. MVD significantly differed between Group B' and C' (P<0.05), but they did not significantly differ between Group A' and B'. CONCLUSIONS: Periodontitis can increase GBF and MVD, but smoking does not cause significant changes. However, the mechanism by which smoking promotes the occurrence and development of chronic periodontitis by influencing gingival microcirculation has not been discussed in this research.


Assuntos
Periodontite Crônica , Humanos , Microcirculação , Fumar
18.
Sci China Life Sci ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31728829

RESUMO

We attempted to explore a noninvasive, easily applicable and economically affordable therapy for retinopathy of prematurity (ROP). Rat pups were raised in 80% oxygen from postnatal day 7 to P12, and returned to room air. Travoprost eye drops were administered twice a day for 7 days, to reduce intraocular pressure (IOP) by about 20%. Immunohistochemical staining was performed to visualize vessel endothelial cells, to analyze retinal neurons and cytoarchitecture. Behavioral experiments were carried out to test visual acuity and contrast sensitivity. At the end of the 7-day treatment, the number of vessels extending to the vitreous body was significantly reduced and retinal vessel density increased. This improvement was maintained to the end of the 12th week. In the central retina of the model group, the horizontal cells were completely wiped out, the outer plexiform layer was undetectable, and the rod bipolar cell dendrites sprouted into the outer nuclear layer. The treatment partially reverted these architectural changes. Most importantly, behavioral experiments revealed significantly improved visual acuity and contrast sensitivity in the treated group. Therefore, reducing IOP could potentially serve as a safe and economical measure to treat ROP.

19.
Artigo em Inglês | MEDLINE | ID: mdl-31761321

RESUMO

BACKGROUND: Hepcidin is a key regulator of iron homeostasis. Some studies showed that exogenous hepcidin decreased the expression of divalent metal transporter (DMT1) rather than ferroportin(FPN1) to regulate renal iron metabolism. This study explored the effects of hepcidin synthesized by the kidney and its mechanism of iron regulation. METHODS: In the in vivo experiments, mice were divided into a unilateral ureter obstruction (UUO) model group and a sham operation group, and mice in the UUO model group were sacrificed on days 1, 3, 5 and 7. The expression of renal hepcidin, FPN1, DMT1 and the retention of renal iron were studied. In the in vitro experiments, we overexpressed hepcidin in HK-2 cells. Then we tested the expression of renal hepcidin, FPN1, DMT1 and observed the production of intracellular ferrous ions. RESULTS: Renal hepcidin expression was consistently higher in the UUO group than in the sham group from the first day. The expression of FPN1 gradually decreased, and the expression of DMT1 gradually increased in the UUO model. Intracellular ferrous ions significantly increased on the first day of the UUO model. In hepcidin overexpressed HK-2 cells, the expression of FPN1 was decreased, while the expression of DMT1 has no significant change. In addition, production of intracellular ferrous ions increased. CONCLUSION: local hepcidin can regulate iron metabolism in the kidney by adjusting the expression of FPN1.

20.
Am J Prev Med ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31761514

RESUMO

INTRODUCTION: Beginning September 3, 2014, CVS Health stopped selling tobacco products in all of its retail stores nationwide. This study assessed the impact of removing tobacco sales from CVS Health on cigarette smoking behaviors among U.S. adult smokers. METHODS: CVS Health retail location data (2012-2016) were linked with data from the Behavioral Risk Factor Surveillance System, a phone-based survey of the non-institutionalized civilian population aged ≥18 years. Using a difference-in-differences regression model, quit attempts and daily versus nondaily smoking were compared between smokers living in counties with CVS stores and counties without CVS stores, before and after CVS's removal of tobacco sales. Control variables included individuals' sociodemographic and health-related variables, state tobacco control variables, and urban status of counties. Analyses were conducted in 2018. RESULTS: During the 2-year period following the removal of tobacco sales from CVS Health, smokers living in counties with high CVS density (≥3.5 CVS stores per 100,000 people) had a 2.21% (95% CI=0.08, 4.33) increase in their quit attempt rates compared with smokers living in counties without CVS stores. This effect was greater in urban areas (marginal effect: 3.03%, 95% CI=0.81, 5.25); however, there was no statistically significant impact in rural areas. Additionally, there was no impact on daily versus nondaily smoking in either urban or rural areas. CONCLUSIONS: Removing tobacco sales in retail pharmacies could help support cessation among U.S. adults who are attempting to quit smoking, particularly in urban areas.

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