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1.
Int J Mol Sci ; 22(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33810107

RESUMO

Transmembrane proteins are involved in an array of stress responses, particularly in thermo-sensation and thermo-regulation. In this study, we performed a genome-wide identification and characterization of the Transient Receptor Potential (TRP) genes in the Pacific oyster (Crassostrea gigas) and investigated their expression profiles after heat stress to identify critical TRPs potentially associated with thermal regulation. A total of 66 TRP genes were identified in the C. gigas, which showed significant gene expansion and tandem duplication. Meta-analysis of the available RNA-Seq data generated from samples after acute heat stress revealed a set of heat-inducible TRPs. Further examination of their expression profiles under chronic heat stress, and comparison between C. gigas and C. angulata, two oyster species with different tolerance levels to heat stress, led to the identification of TRPC3.6, TRPC3.7, and TRPV4.7 as important TRPs involved in thermal regulation in oysters. This work provided valuable information for future studies on the molecular mechanism of TRP mediated thermal tolerance, and identification of diagnostic biomarker for thermal stress in the oysters.

2.
J Phys Chem A ; 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823591

RESUMO

This study investigates the fluorescence quenching mechanism of formaldehyde detection probe Naph1 and its contrast probe Naph3 in water samples and discussed the effect of the electron-donating group and electron-withdrawing group on fluorescence characteristics based on density functional theory (DFT) and time-dependent density functional theory (TD-DFT). We optimized the structures of the four probes Naph1, Naph1-S, Naph3, and Naph3-S (Scheme 1) and calculated the absorption and emission spectra, which were in good agreement with the experiment. Frontier molecular orbitals (FMOs) were used to analyze the charge arrangement in the excited state. To investigate the intramolecular proton transfer (ESIPT) phenomenon, a potential energy curve was constructed. The amount of fragment charge transfer was analyzed by the IFCT method, and then it was determined whether there was an intramolecular charge transfer (ICT) process. It was found that there was an ICT process in Naph3. The electronic effect of the functional groups did not determine the ICT characteristics and the fluorescence characteristics of the substance. Furthermore, the spin-orbit coupling  (SOC) constant based on the intersystem crossing (ISC) was supplemented, which showed that the fluorescence quenching of Naph1 and Naph3 was caused by the ISC and the corresponding quenching of Naph3-S was caused by charge transfer (CT) in the excited state.

3.
Polymers (Basel) ; 13(7)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807127

RESUMO

Based on additive manufacturing of wood flour and polyhydroxyalkanoates composites using micro-screw extrusion, device and process parameters were evaluated to achieve a reliable printing. The results show that the anisotropy of samples printed by micro-screw extrusion is less obvious than that of filament extrusion fused deposition modeling. The type of micro-screw, printing speed, layer thickness, and nozzle diameter have significant effects on the performance of printed samples. The linear relationship between the influencing parameters and the screw speed is established, therefore, the performance of printed products can be controlled by the extrusion flow rate related to screw speed.

4.
Clin Cancer Res ; 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33811153

RESUMO

PURPOSE: The limited efficacy of chimeric antigen receptor (CAR) T cell therapies with solid malignancies prompted us to test whether epigenetic therapy could enhance the antitumor activity of B7-H3 CAR T cells with several solid cancer types. EXPERIMENTAL DESIGN: We evaluated B7-H3 expression in many human solid cancer and normal tissue samples. The efficacy of the combinatorial therapy with B7-H3.CAR-T cells and the deacetylase inhibitor SAHA with several solid cancer types and the potential underlying mechanisms were characterized with in vitro and ex vivo experiments. RESULTS: B7-H3 is expressed in most of the human solid tumor samples tested, but exhibits a restricted expression in normal tissues. B7-H3.CAR-T cells selectively killed B7-H3 expressing human cancer cell lines in vitro A low dose of SAHA upregulated B7-H3 expression in several types of solid cancer cells at the transcriptional level and B7-H3.CAR expression on human transgenic T cell membrane. In contrast, the expression of immunosuppressive molecules, such as CTLA-4 and TET2, by T cells was downregulated upon SAHA treatment. A low dose of SAHA significantly enhanced the antitumor activity of B7-H3.CAR-T cells with solid cancers in vitro and ex vivo, including orthotopic PDX and metastatic models treated with autologous CAR-T cell infusions. CONCLUSIONS: Our results show that our novel strategy which combines SAHA and B7-H3.CAR-T cells enhances their therapeutic efficacy with solid cancers and justify its translation to a clinical setting.

5.
BMC Pregnancy Childbirth ; 21(1): 279, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33832462

RESUMO

BACKGROUND: Vitamin D deficiency is a global public health issue in women and children and is associated with adverse impacts on child growth, such as rickets. However, prior studies have mainly focused on measuring vitamin D levels in singleton pregnant women and their offspring, and very limited studies have revealed the prevalence of vitamin D deficiency in twin pregnant women and their offspring. The aim of this study was to investigate vitamin D levels in twin-pregnant women and their neonates. We also explored the correlation of maternal vitamin D levels with neonatal outcomes and infant growth. METHODS: A prospective subcohort investigation was carried out among 72 dichorionic, diamniotic twin-pregnant mothers and their twin offspring from the Longitudinal Twin Study. Peripheral blood was collected from the mothers in the third trimester, and cord blood was collected from neonates at birth to identify 25[OH]D levels. Data on the characteristics of the mothers and neonates were collected. Infant growth data and food sensitivities were also collected. RESULTS: The average maternal 25[OH]D level was 31.78 ng/mL, with 19.4% being deficient and 20.8% insufficient, while the average neonatal 25[OH]D level was 15.37 ng/mL, with 99.3% being deficiency or insufficient. A positive correlation was found between maternal and neonatal 25[OH]D levels (beta-value: 0.43, 95% CI: 0.37, 0.49). Interestingly, the higher the maternal 25[OH]D level was, the smaller the cotwin birthweight discordance (beta-value: -2.67, 95% CI: - 5.11, - 0.23). In addition, the infants of mothers with vitamin D deficiency were more likely to be allergic to foods at 6 months than those of mothers with vitamin D sufficiency. CONCLUSIONS: Twin neonates were at high risk of vitamin D deficiency, although their mothers' vitamin D deficiency partially improved. Higher maternal vitamin D levels were associated with smaller discordance of cotwin birthweight. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR-OOC-16008203 , 1st April 2016.

6.
Aging (Albany NY) ; 132021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33833130

RESUMO

Long noncoding RNAs (lncRNAs) have emerged as the key regulators in the pathogenesis of human disorders. This study aimed to investigate the role of lncRNA-IPW in the progression of choroidal neovascularization (CNV) and the underlying molecular mechanism. IPW was significantly up-regulated in the choroidal tissues of laser-induced CNV mice and in the endothelial cells in response to hypoxic stress. IPW silencing led to reduced formation of CNV in laser-induced CNV model and ex vivo choroidal sprouting model, which could achieve similar therapeutic effects of anti-VEGF on CNV formation. Silencing or transgenic overexpression of IPW could alter endothelial cell viability, proliferation, migration, and tube formation ability in vitro. Mechanistically, IPW silencing led to increased expression of miR-370. Increased miR-370 could mimic the effects of IPW silencing on CNV formation and endothelial angiogenic phenotypes in vivo and in vitro. This study suggests that IPW silencing is a promising strategy for the treatment of neovascular ocular diseases.

7.
Mod Rheumatol ; : 1-10, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33705241

RESUMO

OBJECTIVES: Pyroptosis has been found implicated in several diseases, however, whether it was involved in gouty arthritis remained unclear. Our study was performed to uncover the role of pyroptosis in gouty arthritis based on a mice model. METHODS: Mouse gouty arthritis model was established by injections of potassium oxonate (PO), monosodium urate (MSU) and pyroptosis suppressor disulfiram. The diameter of the ankle joints was measured, and ankle joints morphology was observed with hematoxylin-eosin (H&E) staining. Uric acid, creatinine and blood urea nitrogen (BUN) concentrations were measured, while cytokines level and xanthine oxidase (XOD) activity were quantified. Relative pyroptosis markers expressions were determined using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. RESULTS: In mouse model, PO and MSU injections cause damage to right ankle, increase the root thickness ratio and uric acid, creatinine and BUN levels in serum and decrease the uric acid and creatinine levels in urine. Also, under PO and MSU treatment, up-regulated XOD activity, inflammatory cytokines levels and pyroptosis markers expressions are observed. Negative regulation of mice injury by disulfiram treatment is also observed. CONCLUSION: Pyroptosis inhibition might alleviate PO- and MSU-induced gouty arthritis, providing possible therapeutic strategies for gouty arthritis.

8.
Neural Plast ; 2021: 6641506, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777135

RESUMO

Flaccid paralysis in the upper extremity is a severe motor impairment after stroke, which exists for weeks, months, or even years. Electroacupuncture treatment is one of the most widely used TCM therapeutic interventions for poststroke flaccid paralysis. However, the response to electroacupuncture in different durations of flaccid stage poststroke as well as in the topological configuration of the cortical network remains unclear. The objectives of this study are to explore the disruption of the cortical network in patients in different durations of flaccid stage and observe dynamic network reorganization during and after electroacupuncture. Resting-state networks were constructed from 18 subjects with flaccid upper extremity by partial directed coherence (PDC) analysis of multichannel EEG. They were allocated to three groups according to time after flaccid paralysis: the short-duration group (those with flaccidity for less than two months), the medium-duration group (those with flaccidity between two months and six months), and the long-duration group (those with flaccidity over six months). Compared with short-duration flaccid subjects, weakened effective connectivity was presented in medium-duration and long-duration groups before electroacupuncture. The long-duration group has no response in the cortical network during electroacupuncture. The global network measures of EEG data (sPDC, mPDC, and N) indicated that there was no significant difference among the three groups. These results suggested that the network connectivity reduced and weakly responded to electroacupuncture in patients with flaccid paralysis for over six months. These findings may help us to modulate the formulation of electroacupuncture treatment according to different durations of the flaccid upper extremity.

9.
Vascul Pharmacol ; : 106854, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33781961

RESUMO

Sitagliptin, a dipeptidyl peptidase-4(DPP-4) Inhibitor, has been found to have an anti-atherosclerotic effect. Since apoptosis of vascular smooth muscle cells (VSMCs) contributes to the occurrence of diabetic atherosclerosis. This study aimed to examine whether sitagliptin suppresses the atherosclerosis progression to hyperglycemia in a low-dose streptozotocin (STZ)-induced diabetic mouse model, and then investigated the effect of sitagliptin on VSMCs apoptosis and its underlying mechanism. In vivo studies, eight-week-old low-dose STZ-induced diabetic apolipoprotein E (apoE)-deficient (apoE-/-) mice fed a high-fat diet were administered a DPP-4 inhibitor, sitagliptin, 200 mg/kg/day, or Lantus insulin by daily subcutaneous injection of 1 unit/mouse over a period of 12 weeks. Aortic atherosclerosis and apoptosis in the plaque were determined using dUTP-biotin nick end labeling (TUNEL) staining and immunohistochemistry. In vitro studies utilized the VSMCs for determination of glucagon-like peptide 1 receptor (GLP-1R) and DPP-4 expression and flow cytometry and Western blotting were used to determine apoptosis and protein expression, respectively. Sitagliptin significantly reduced atherosclerotic lesion area (7.00 ±â€¯0.13 vs. 12.80 ±â€¯2.7%, p = 0.003) and suppressed vascular smooth muscle cell apoptosis (2.30 ±â€¯1.34 vs. 4.8 ±â€¯1.93%, p = 0.003) compared with vehicle treatment. In addition, sitagliptin significantly increased the expression of ß-catenin in the aortic tissue(0.56 ±â€¯0.13 vs.0.17 ±â€¯0.02, p = 0.008)compared with vehicle treatment. In cultured mouse VSMCs, sitagliptin enhanced GLP-1 activity significantly retarded oxidative stress (H2O2)-induced apoptosis compared with GLP-1 or sitagliptin alone. Sitagliptin increased GLP-1-induced cytosolic levels of ß-catenin compared with GLP-1 alone, resulted in increasing the expression of survivin, and suppressed proinflammatory cytokines, i.e., interleukin-6(IL-6) and tumor necrosis factor-alpha(TNF-α), production in response to H2O2. In conclusion, these results indicated that the anti-atherosclerotic effect of sitagliptin is mediated, at least in part, by its inhibition of VSMCs apoptosis.

10.
Mutat Res ; 863-864: 503321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33678246

RESUMO

Previous studies showed that the yield of cobalt-60 γ-rays-induced nucleoplasmic bridges (NPB) in human peripheral blood lymphocytes is dose dependent. However, the influence of the radiation quality and dose rates on NPB frequencies has not been investigated. The present study aimed to investigate NPB frequencies in human peripheral blood lymphocytes induced by carbon ions and explore the dose rate effect on cobalt-60 γ-rays-induced NPB. To establish dose-response curves, human peripheral blood samples were irradiated with 0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 and 8.0 Gy of carbon ions at a dose rate of 3.0 Gy/min in vitro. To explore the dose rate effect, human peripheral blood samples were irradiated with 2.0 and 5.0 Gy of cobalt-60 γ-rays at dose rates of 0.2, 0.5, 1.0, 3.0, 5.0 and 10.0 Gy/min in vitro. NPB and micronuclei (MN) in binucleated cells were analyzed with the cytokinesis-block micronucleus cytome assay. Results showed that the dose-response curve of carbon ion-induced NPB frequencies follow a linear-quadratic model (R2 = 0.934). The relative biological effectiveness (RBE) values of carbon ions to cobalt-60 γ-rays decreased with increased NPB frequencies (ranging from 2.47 to 5.86). Compared with group 1.0 Gy/min, the NPB frequencies in groups 10.0 Gy/min (2.0 Gy), 5.0 and 10.0 Gy/min (5.0 Gy) were decreased significantly (P < 0.05). Carbon ion-induced NPB in human peripheral blood lymphocytes have a good dose-response relationship. Cobalt-60 γ-rays-induced NPB frequencies are affected by the specific dose rate.


Assuntos
Radioisótopos de Cobalto , Dano ao DNA , Raios gama/efeitos adversos , Linfócitos/metabolismo , Adulto , Relação Dose-Resposta à Radiação , Humanos , Linfócitos/patologia , Masculino , Testes para Micronúcleos
11.
Int J Radiat Biol ; : 1-7, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33704009

RESUMO

PURPOSE: The objective of this research was to explore the dose-effect relationships of dicentric plus ring (dic + r), micronucleus (MN) and nucleoplasmic bridges (NPB) induced by carbon ions in human lymphocytes. MATERIALS AND METHODS: Venous blood samples were collected from three healthy donors. 12C6+ ions beam was used to irradiate the blood samples at the energy of 330 MeV and linear energy transfer (LET) of 50 keV/µm with a dose rate of 1 Gy/min in the spread-out Bragg peak. The irradiated doses were 0 (sham irradiation), 1, 2, 3, 4, 5 and 6 Gy. Dic + r chromosomes aberrations were scored in metaphases. The cytokinesis-block micronucleus cytome (CBMN) was conducted to analyze MN and NPB. The maximum low-dose relative biological effectiveness (RBEM) values of the induction of dic + r, MN and NPB in human lymphocytes for 12C6+ ions irradiation was calculated relative to 60Co γ-rays. RESULTS: The frequencies of dic + r, MN and NPB showed significantly increases in a dose-depended manner after exposure to 12C6+ ions. The distributions of dic + r and MN exhibited overdispersion, while the distribution of NPB agreed with Poisson distribution at all doses. Linear-quadratic equations were established based on the frequencies of dic + r and MN. The dose-response curves of NPB frequencies followed a linear model. The derived RBEM values for dic + r, MN and NPB in human lymphocytes irradiated with 12C6+ ions were 8.07 ± 2.73, 2.69 ± 0.20 and 4.00 ± 2.69 in comparison with 60Co γ-rays. CONCLUSION: The dose-response curves of carbon ions-induced dic + r, MN and NPB were constructed. These results could be helpful to improve radiation risk assessment and dose estimation after exposed to carbon ions irradiation.

12.
Ann Palliat Med ; 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33752428

RESUMO

BACKGROUND: Neuromyelitis optica spectrum disorders (NMOSD) are associated with recurrent episodes of optic neuritis and transverse myelitis, often resulting in high attack-related disability. Therapeutic apheresis has been recommended as a second-line treatment for steroid-refractory NMOSD. To assess the efficacy and safety of two apheresis techniques, lymphoplasmapheresis (LPE) and therapeutic plasma exchange (TPE), in refractory NMOSD and to provide a new treatment option for patients with refractory NMOSD. METHODS: This retrospective study examined NMOSD patients who had undergone either LPE or TPE treatment between January 2015 and January 2018. The patients were monitored for improvements in disabilities, incidences of adverse reactions, and safety of the procedure over a one-year follow-up period. The primary outcome measures included changes in the visual outcome scale (VOS) score, the expanded disability status scale (EDSS), and the annualized relapse rate (ARR). RESULTS: Neurological function and objective response rates were significantly improved in 76.5% of patients treated with LPE and 83.3% of patients treated with TPE. There were no significant differences in the two treatment groups (P=0.392). Similarly, there were no differences in the reduction in the relative relapse rate between the two groups (P=0.494). Adverse reactions, mostly of mild or moderate intensity, were recorded in 9.3% of procedures in 38% of patients. The most commonly observed adverse events (AEs) were similar between the two treatment cohorts. CONCLUSIONS: Patients treated with LPE showed improved neurological function comparable to that reported with TPE treatment. No superiority was shown for either of the apheresis techniques.

13.
Ophthalmol Glaucoma ; 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33722789

RESUMO

PURPOSE: In this study, we describe common demographic and clinical characteristics of the glaucoma patient population attending vision rehabilitation. DESIGN: Cross sectional study. PARTICIPANTS: Patients attending a hospital-based vision rehabilitation center with a primary ocular diagnosis of glaucoma. METHODS: Participant's charts were retrospectively reviewed. Data extracted from medical records included demographics, referring physician, past ocular history, glaucoma diagnosis, past ocular surgery, intraocular pressure, optic nerve findings, results of a functional intake assessing activities of daily living (ADLs), depression, visual hallucinations, best-corrected visual acuity (BCVA), mean deviation (MD) scores on visual field testing, and log contrast sensitivity (CS). MAIN OUTCOME MEASURES: Participant demographic information, ocular history, self-reported difficulty with ADLs, depression, visual hallucinations, BCVA, visual field, and CS. RESULTS: The mean age of patients in this study was 77 years and ranged from nine to 103. Ninety percent of patients were referred to vision rehabilitation by an ophthalmologist. Median BCVA was 20/50. Fifty-five percent of patients were functionally monocular, and for all patients there was a median 9 line difference in BCVA between eyes. Median MD score was -13.95 dB. Median CS was 1.05. Patients reported having the greatest difficulty with reading (88%), writing (72%), and mobility (67%). Seventy-eight percent of patients stopped driving and 12% reported difficulty driving. Among those experiencing depression, there was a 4:1 ratio of depressed patients having difficulty with mobility. One third of patients experienced visual hallucinations. CONCLUSIONS: Most glaucoma patients attending vision rehabilitation are not legally blind, but many are functionally monocular. This may cause greater difficulty performing functions that require the use of binocularity. Increasing the referral of younger glaucoma patients to vision rehabilitation may help patients learn to how cope with the loss of visual function that occurs over time.

14.
Aging (Albany NY) ; 132021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647882

RESUMO

It is widely accepted that estrogen can be replaced by phytoestrogens to treat postmenopausal cardiovascular disease and possibly decrease the risk of breast cancer. However, few studies have investigated the effects of phytoestrogens on vascular endothelial cells (ECs). In the present study, we show that the phytoestrogen calycosin (20 µM) stimulated the proliferation of ECs (HUVECs and HMEC-1) but inhibited the growth of breast cancer cells (BCCs) expressing ERα (MCF-7 and T47D). Here we provide evidence for the presence of a positive feedback loop between ERα and long noncoding RNA RP11-65M17.3 in both normal and cancer cells, and calycosin stimulated this feedback loop in ECs but decreased RP11-65M17.3 expression in BCCs. Subsequently, the calycosin-induced activation of this loop decreased the expression of the target of BRIP1 (BRCA1 interacting protein C-terminal helicase 1), increased the phosphorylation of Akt and ERK1/2, and finally inhibited the cleavage of PARP-1 in ECs. In nude mice bearing MCF-7 xenografts, calycosin did not stimulate tumor growth as strongly as 17ß-estradiol. Together, these results suggest that calycosin promotes the proliferation of ECs, and notable inhibits the growth of BCCs. A possible reason for these results is the involvement of a feedback loop between ERα and RP11-65M17.3.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33759443

RESUMO

OBJECTIVE: To compare survival outcome among the patients with concurrent small cell lung cancer (SCLC) and diabetes mellitus (DM) using metformin or without metformin. METHODS: A systematic literature search for relevant studies up to Oct 2020 was conducted. Outcome of the included studies included overall survival (OS) or disease-free survival (DFS). HR values were pooled to estimate the effect of metformin on survival outcomes. RESULTS: 6 studies with 539 participants with both SCLC and diabetes were included in the analysis. The patients with metformin usage had significantly longer OS and DFS than those without metformin usage [OS: HR=0.72 (0.53-0.98), p=0.04; DFS: HR= 0.59 (0.45-0.76), p<0.0001)]. The studies included were not significantly different in the two analyses by heterogeneity test. There was no obvious publication bias. CONCLUSIONS: Metformin may improve survival among patients with concurrent SCLC and DM. Further investigations especially randomized control trials are warranted, especially among the patients who do not have diabetes.

16.
Bone ; 147: 115938, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33766805

RESUMO

Sleep problems are common in the general population and have been linked to bone health, falls risk and fracture. However, longitudinal studies on sleep-bone health outcomes are lacking and no study has investigated whether an increased risk of fracture is attributable to sleep-related low bone mineral density (BMD) and an increased risk of falls. This study was designed to examine the associations of sleep disturbance with bone mineral density (BMD), risk of falls and fractures over 10.7 years. The analyses were performed in a population-based cohort study with 1099 participants (mean age 62.9 years) enrolled at baseline, and 875, 768 and 563 participants traced at a mean follow-up of 2.6, 5.1 and 10.7 years, respectively. At each visit, self-reported sleep disturbance was recorded. BMD (by dual-energy x-ray absorptiometry), falls risk score and fracture were measured at each visit. The short-form Physiological Profile Assessment was used to measure falls risk score expressed as Z-score. Fractures were self-reported. Mixed-effects model and generalized estimating equations were used for the analyses. In multivariable analysis, there was a dose-response relationship between the extent of sleep disturbance and falls risk score with the strongest association in those reporting the worst sleep disturbance (ß = 0.15/unit; 95%CI 0.02-0.28). The worst sleep disturbance was associated with an increased risk of any (relative risk [RR] 1.30/unit; 95%CI 1.01-1.67) and vertebral fracture (RR 2.41/unit; 95%CI 1.00-5.80) compared with those reporting no interrupted sleep. Women but not men with sleep disturbance had a higher risk of vertebral fracture (RR: 2.07 to 6.02, P < 0.05). These were independent of covariates, hip BMD and falls risk. There was no statistically significant association between sleep disturbance and BMD at the hip, spine or total body. Sleep disturbance was independently associated with a greater falls risk score and an increased risk of fractures. Further research is needed to confirm and identify underlying mechanisms for these associations.

17.
Math Biosci Eng ; 18(2): 1425-1449, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33757192

RESUMO

In this study, we explore a stochastic age-dependent cooperative Lotka-Volterra (LV) system with an environmental noise. By applying the theory of M-matrix, we prove the existence and uniqueness of the global solution for the system. Since the stochastic age-dependent cooperative LV system cannot be solved explicitly, we then construct an Euler-Maruyama (EM) numerical solution to approach the exact solution of the system. The convergence rate and the pth-moment boundedness of the scheme have also been obtained. Additionally, numerical experiments have been conducted to verify our theoretical results.

18.
Food Chem ; 349: 129144, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33540218

RESUMO

Ferritin is an iron-containing protein and functions in the maintenance of iron balance in organisms. Currently the interaction among ferritin, ion iron, and food bioactive compounds is still unclear. In this study, the mechanism underlying the interaction of ferritin, ion iron, and chlorogenic acid was investigated, as well as the effect of chlorogenic acid on the physicochemical properties of ferritin. The results showed that chlorogenic acid could interact with Fe(III) to form chlorogenic acid-Fe(III) complexes, which then bonded with ferritin via hydrogen bonds in the ferritin-chlorogenic acid-Fe(III) complexes. The chlorogenic acid showed a high efficiency in Fe(II) chelation and hydroxyl radical (•OH) capture, and could promote iron oxidation and iron release induced by ferritin. Chlorogenic acid could also effectively reduce the polymerization extent of ferritin induced by Fe(III) and Fe(II). This study elucidates the interactions of multiple components in foodstuffs by using a protein-metal-polyphenol model.


Assuntos
Ácido Clorogênico/metabolismo , Ácido Clorogênico/farmacologia , Ferritinas/química , Ferritinas/metabolismo , Ferro/metabolismo , Ferro/farmacologia , Multimerização Proteica/efeitos dos fármacos , Oxirredução , Ligação Proteica , Estrutura Quaternária de Proteína
19.
Food Chem ; 349: 129164, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550022

RESUMO

Premna microphylla turcz leaf juice with polysaccharides (PMPs) as its main component, are raw material of jelly-like Chinese traditional food "Guanyin tofu", which were also experiencedly used to relieve inflammation-related symptoms. Here three kinds of PMPs were extracted in alkaline (APMP), water (WPMP) and acidic (HPMP) conditions, being characteristic of RG I, high- and low-methoxyl HG pectin, respectively, in amorphous form with diverse surface microstructures, among which APMP predominantly composed of Glucose instead of galacturonic acid, showing wider molecular weight distribution and more branched chains. PMPs showed remarkable radical scavenging capability, and especially APMP at concentrations above 50 µg/mL effectively inhibited the reactive oxygen species and malondialdehyde production in LPS-stimulated RAW 264.7 macrophages, by enhancing enzymatic activities of endogenous superoxide dismutase, glutathione peroxidase and catalase, and accordingly alleviated inflammatory cytokines. Thus, PMPs could be promising non-toxic natural dietary supplement to improve chronic inflammation-induced diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Lamiaceae/química , Macrófagos/efeitos dos fármacos , Pectinas/farmacologia , Folhas de Planta/química , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Citocinas/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/enzimologia , Macrófagos/metabolismo , Camundongos , Pectinas/química , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo
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