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1.
Analyst ; 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001065

RESUMO

This work describes a two-chip acoustofluidic platform for two-dimensional (2D) manipulation of microparticles in a closed microchamber on a reusable surface acoustic wave (SAW) device. This platform comprises two microfabricated chips: (1) a detachable silicon superstrate enclosed by a PDMS microfluidic chamber and (2) a reusable SAW device for generating standing SAW (SSAW), which is typically an expensive component. Critical to such a two-chip acoustofluidic platform is the selection of a suitable coupling agent at the interface of the SAW device and superstrate. To this end, we applied a polymer thin film as a coupling agent that balances between acoustic coupling efficiency, stability over time, and reusability. Recycling of the SAW device lowers the cost-barrier for acoustofluidic particle manipulation. The SSAW is transmitted into the silicon superstrate via the coupling agent to form a standing Lamb wave (SLW) to trap and move microparticles. The reported two-chip strategy enables the single-use microfluidic superstrates to avoid chemical and biological contaminations, while maintaining the merits of acoustofluidic manipulation of being noncontact and label-free and applicable to a wide range of microparticles with different shapes, density, polarity, and electrical properties.

2.
FEBS Open Bio ; 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33010109

RESUMO

Fluorosis is a common disease characterized by disruptions in bone metabolism and enamel development. The production of reactive oxygen species (ROS) is thought to play an important role in fluorosis. Gastrodin (4-hydroxybenzylalcohol4-O-beta-D-glucopyranoside) has been reported to have anti-oxidative activity, and so here we examined whether gastrodin has protective effects against oxidative stress and bone tissue toxicity in rats with fluorosis. Wistar rats were given different doses of gastrodin one month after fluoride administration, and samples of blood, bone and teeth were collected after 2, 3 and 4 months, GSH-Px, CAT and SOD levels in the fluorosis group were lower than those in the control group. Gastrodin treatment ameliorated oxidative stress and fluoride accumulation in rats induced by fluoride; treatment with 400mg/kg gastrodin protected trabecular bone structure and reduced femur and alveolar bone injury in rats with fluorosis. Enhanced expression of Caspase 3, Caspase 9, and Bax and decreased expression of Bcl-2 induced by fluoride were also reversed by gastrodin. In summary, the present data suggest that gastrodin, and in particular a dose of 400mg/kg, can improve the antioxidative capacity of rats, reduce concentration of fluoride in tissues, alleviate bone damage, and modulate expression of Bcl-2, Bax, Caspase 3 and Caspase 9.

3.
Phys Chem Chem Phys ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33025995

RESUMO

The practical application of existing diluted magnetic semiconductors (DMSs) depends crucially on improving their room temperature ferromagnetism. Doping, as an effective method, can be used to modulate the physical properties of semiconducting materials. Herein, we report on the observation of significant RTFM in a III-VI semiconductor compound doped with nonmagnetic impurities, Cu-doped In2S3 quantum dots (QDs) grown by a gas-liquid phase chemical deposition method. The effect of Cu doping on the electronic structure and optical and magnetic properties of In2S3 is studied systematically. The UV-vis and photoluminescence (PL) spectra reveal that Cu-doped In2S3 can moderately benefit the optical properties of pristine In2S3. Magnetic measurements show that the pristine In2S3 and Cu-doped In2S3 QDs exhibit obvious RTFM, which is ascribed to the role of intrinsic defects in accordance with the bound-magnetic-polaron (BMP) theory. Furthermore, first-principles calculations based on the spin density functional theory indicate that In vacancies and their complexes with Cu dopants play a crucial role in inducing ferromagnetism. These results suggest that the Cu-doped In2S3 QDs are promising candidates for spintronics and magneto-optical applications.

4.
Biol Res ; 53(1): 44, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008472

RESUMO

BACKGROUND: Atherosclerosis (AS) is the main pathological basis of coronary heart disease, cerebral infarction and peripheral vascular disease, which seriously endanger people's life and health. In recent years, long non-coding RNA (lncRNA) has been found to be involved in gene expression regulation, but the research on AS is still in the initial stage. In this study, we mainly studied the role of HCG11 in patients with AS. Quantitative Real-time Polymerase Chain Reaction (QRT-PCR) was used to detect the expression of HCG11 and miR-144 in the serum of AS patients and healthy volunteers. Oxidation Low Lipoprotein (Ox-LDL), interleukin-6 (IL-6) and tumor necrosis factor α (TNF α) radiation were used to establish human vascular smooth muscle cells (VSMCs) in vitro model. Cell proliferation was determined by Cell Counting Kit-8 (CCK-8) assay. The apoptosis rate was determined by flow cytometry (FACS) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) staining. The expression levels of Forkhead box protein F1 (FOXF1), B cell lymphoma-2 (Bcl-2) and BCL2-Associated X (Bax) were detected by qRT-PCR. Luciferase gene reporter and RNA pull down experiments confirmed the relationship between HCG11 and miR-144, miR-144 and FOXF1. RESULTS: This study showed that HCG11 was significantly upregulated in patients with AS, while miR-144 was down-regulated in patients with AS. Ox-LDL and IL-6 in VSMCs induced up-regulation of HCG11 and down-regulation of miR-144. Overexpression of HCG11 promoted the proliferation and inhibited apoptosis of VSMCs. Luciferase gene reporter gene assay showed that HCG11 could bind to miR-144, and miR-144 could bind to FOXF1. Overexpression of miR-144 reversed the effect of HCG11 on VSMCs. CONCLUSIONS: LncRNA HCG11 regulates proliferation and apoptosis of vascular smooth muscle cell through targeting miR-144-3p/FOXF1 axis.

5.
Front Immunol ; 11: 2071, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013877

RESUMO

We specify the clinical features of a spontaneous experimental autoimmune uveitis (EAU) model, in which foreign hen-egg lysozyme (HEL) is expressed in the retina, controlled by the promoter for interphotoreceptor retinol binding protein (IRBP). We previously reported 100% P21 (post-partum day) IRBP:HEL single transgenic (sTg) mice, when crossed to transgenic T cell receptor mice (3A9) generating the double transgenic (dTg) genotype, develop EAU despite profound lymphopenia (thymic HEL-specific T cell deletion). In this work, we characterized the immune component of this model and found conventional dTg CD4+ T cells were less anergic than those from 3A9 controls. Furthermore, prior in vitro HEL-activation of 3A9 anergic T cells (Tan) rendered them uveitogenic upon adoptive transfer (Tx) to sTg mice, while antigen-experienced (AgX, dTg), but not naïve (3A9) T cells halted disease in P21 dTg mice. Flow cytometric analysis of the AgX cells elucidated the underlying pathology: FoxP3+CD25hiCD4+ T regulatory cells (Treg) comprised ∼18%, while FR4+CD73+FoxP3-CD25lo/-CD4+ Tan comprised ∼1.2% of total cells. Further Treg-enrichment (∼80%) of the AgX population indicated FoxP3+CD25hiCD4+ Treg played a key role in EAU-suppression while FoxP3-CD25lo/-CD4+ T cells did not. Here we present the novel concept of dual immunological tolerance where spontaneous EAU is due to escape from anergy with consequent failure of Treg induction and subsequent imbalance in the [Treg:Teffector] cell ratio. The reduced numbers of Tan, normally sustaining Treg to prevent autoimmunity, are the trigger for disease, while immune homeostasis can be restored by supplementation with AgX, but not naïve, antigen-specific Treg.

6.
Insect Biochem Mol Biol ; 127: 103476, 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33053387

RESUMO

Whether a female honey bee (Apis mellifera) develops into a worker or a queen depends on her nutrition during development, which changes the epigenome to alter the developmental trajectory. Beekeepers typically exploit this developmental plasticity to produce queen bee by transplanting worker larvae into queen cells to be reared as queens, thus redirecting a worker developmental pathway to a queen developmental pathway. We studied the consequences of this manipulation for the queen phenotype and methylome over four generations. Queens reared from worker larvae consistently had fewer ovarioles than queens reared from eggs. Over four generations the methylomes of lines of queens reared from eggs and worker larvae diverged, accumulating increasing differences in exons of genes related to caste differentiation, growth and immunity. We discuss the consequences of these cryptic changes to the honey bee epigenome for the health and viability of honey bee stocks.

7.
BMC Surg ; 20(1): 222, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33008379

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) has been declared a global pandemic by the World Health Organization. Patients with cancer are more likely to incur poor clinical outcomes. Due to the prevailing pandemic, we propose some surgical strategies for gastric cancer patients. METHODS: The 'COVID-19' period was defined as occurring between 2020 and 01-20 and 2020-03-20. The enrolled patients were divided into two groups, pre-COVID-19 group (PCG) and COVID-19 group (CG). A total of 109 patients with gastric cancer were enrolled in this study. RESULTS: The waiting time before admission increased by 4 days in the CG (PCG: 4.5 [IQR: 2, 7.8] vs. CG: 8.0 [IQR: 2,20]; p = 0.006). More patients had performed chest CT scans besides abdominal CT before admission during the COVID-19 period (PCG: 22 [32%] vs. CG: 30 [73%], p = 0.001). After admission during the COVID period, the waiting time before surgery was longer (PCG: 3[IQR: 2,5] vs. CG: 7[IQR: 5,9]; p < 0.001), more laparoscopic surgeries were performed (PCG: 51[75%] vs. CG: 38[92%], p = 0.021), and hospital stay period after surgery was longer (7[IQR: 6,8] vs.9[IQR:7,11]; p < 0.001). In addition, the total cost of hospitalization increased during this period, (PCG: 9.22[IQR:7.82,10.97] vs. CG: 10.42[IQR:8.99,12.57]; p = 0.006). CONCLUSION: This study provides an opportunity for our surgical colleagues to reflect on their own services and any contingency plans they may have to tackle the COVID-19 crisis.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Procedimentos Cirúrgicos do Sistema Digestório/estatística & dados numéricos , Laparoscopia/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias/prevenção & controle , Seleção de Pacientes , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Padrões de Prática Médica , Utilização de Procedimentos e Técnicas , Estudos Retrospectivos
8.
BMC Surg ; 20(1): 227, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028297

RESUMO

BACKGROUND: To evaluate the feasibility and safety of robot-assisted retroperitoneal laparoscopic adrenalectomy (RARLA) for large pheochromocytomas (PHEOs; size≥6 cm) compared with retroperitoneal laparoscopic adrenalectomy (RLA). METHODS: Fifty-one patients who underwent adrenalectomy for large PHEOs between March 2016 and January 2019 were enrolled and divided into two groups, including 32 RLA cases and 19 RARLA cases. We compared the perioperative efficacy and long-term follow-up results between the two groups. RESULTS: Preoperative data, including demographics, comorbidities and tumour characteristics, were similar between the groups. Intraoperatively, the RARLA group had a lower incidence of haemodynamic instability (26.3% vs. 56.2%, P = 0.038) and less intraoperative blood loss (100 ml vs. Two hundred milliliter, P = 0.042) than the RLA group. The groups showed no significant differences in operative time or transfusion rates. Postoperatively, the time to diet resumption, time to ambulation, time to drainage removal and postoperative hospital stay were shorter in the RARLA group than in the RLA group (1 d vs. 2 d, P = 0.027; 1 d vs. 2 d, P = 0.034; 3 d vs. 5 d, P = 0.002; 5 d vs. 6 d, P = 0.02, respectively). The groups exhibited no significant differences in the duration of anaesthetic use, complications, or long-term follow-up results for the blood pressure (BP) improvement rate. CONCLUSIONS: Compared with RLA, RARLA is a safe, feasible and even optimized procedure for large PHEOs.

9.
Infect Genet Evol ; : 104585, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33035644

RESUMO

Innate immunity is the first line against the invasion of pathogenic microorganisms. Over the past several years, the antiviral activity and mechanisms of the IFIT5 gene have been confirmed in mammals. However, more information is needed on the functions and molecular mechanisms of IFIT5 in response to viral infection in chickens. In this study, we examined the expression profile of chicken IFIT5 in the different tissues and explored how chicken IFIT5 transduces upstream signaling to the downstream adaptor. Relative expression of IFIT5 was highest in spleen, indicating tissue- and species-specificity. Expression of IFIT5 was significantly up-regulated following Newcastle disease virus (NDV)-, polyinosinic:polycytidylic acid [poly (I:C)]-, and poly(deoxyadenylic-thymidylic)[poly (dA:dT)]-triggered antiviral immune response. Chicken MDA5, MAVS, and IRF7 genes positively regulated the expression of IFIT5, and overexpression with IFIT5 could promote IRF7- and nuclear factor kappa B (NF-κB)-mediated gene expression following transfection with NDV and poly (I:C). These results suggested that chicken IFIT5 is an important enhancer of the innate immunity response.

10.
Zootaxa ; 4768(4): zootaxa.4768.4.4, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33055637

RESUMO

A taxonomic review of the genus Hechinoschema is presented. A new genus, Propedicellus gen. nov., is described, and two new species Propedicellus guoliangi sp. nov. and Propedicellus qiului sp. nov. are described from China. A new combination Propedicellus vitalisi (Pic, 1925) comb. nov. is proposed. A key to species of Propedicellus is presented.

11.
Bioorg Med Chem ; 28(21): 115720, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33065445

RESUMO

An organic small-molecular drug, 4-(1H-indol-3-yl)-2-(p-tolyl)quinazoline-3-oxide 1a was synthesized. It was employed to investigate the binding interaction and mechanism with human serum albumin (HSA). The experimental results indicated that the fluorescence quenching of HSA by 1a is a static quenching process and formation 1a-HSA complex. The site competition experiments revealed that the combination of 1a on HSA are hydrophobic interactions in the IIA domain and hydrogen bonds in IIIA domain of HSA, and the hydrophobic interactions of 1a on HSA are stronger than that of hydrogen bonds. These results were also confirmed by molecular docking theoretic analysis and ANS-hydrophobic fluorescent probe experiment. Synchronous fluorescence experiments showed that the polarity of HSA microenvironment was increase in the interaction process of 1a with HSA. The results of binding distance explored indicated that the combination distance between 1a and HSA is 3.63 nm, which is between 0.5R0 and 1.5R0, revealing the energy transfer between HSA and 1a is non-radiative. These results are very helpful for people to screen out high efficient indoloquinazoline drugs.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33060295

RESUMO

Probing the binding between a microbe and surface is critical for understanding biofilm formation processes, developing biosensors, and designing biomaterials, but it remains a challenge. Here, we demonstrate a method to measure the interfacial forces of bacteria attached to the surface. We tracked the intrinsic fluctuations of individual bacterial cells using an interferometric plasmonic imaging technique. Unlike the existing methods, this approach determined the potential energy profile and quantified the adhesion strength of single cells by analyzing the fluctuations. This method provides insights into biofilm formation and can also serve as a promising platform for investigating biological entity/surface interactions, such as pathogenicity, microbial cell capture and detection, and antimicrobial interface screening.

13.
Mol Neurobiol ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063281

RESUMO

At present, chronic post-surgical pain (CPSP) is difficult to prevent and cure clinically because of our lack of understanding of its mechanisms. Surgical injury induces the upregulation of voltage-gated sodium channel Nav1.7 in dorsal root ganglion (DRG) neurons, suggesting that Nav1.7 is involved in the development of CPSP. However, the mechanism leading to persistent dysregulation of Nav1.7 is largely unknown. Given that nerve growth factor (NGF) induces a long-term increase in the neuronal hyperexcitability after injury, we hypothesized that NGF might cause the long-term dysregulation of Nav1.7. In this study, we aimed to investigate whether Nav1.7 regulation by NGF is involved in CPSP and thus contributes to the specific mechanisms involved in the development of CPSP. Using conditional nociceptor-specific Nav1.7 knockout mice, we confirmed the involvement of Nav1.7 in NGF-induced pain and identified its role in the maintenance of pain behavior during long-term observations (up to 14 days). Using western blot analyses and immunostaining, we showed that NGF could trigger the upregulation of Nav1.7 expression and thus support the development of CPSP in rats. Using pharmacological approaches, we showed that the increase of Nav1.7 might be partly regulated by an NGF/TrkA-SGK1-Nedd4-2-mediated pathway. Furthermore, reversing the upregulation of Nav1.7 in DRG could alleviate spinal sensitization. Our results suggest that the maintained upregulation of Nav1.7 triggered by NGF contributes to the development of CPSP. Attenuating the dysregulation of Nav1.7 in peripheral nociceptors may be a strategy to prevent the transition from acute post-surgical pain to CPSP.

14.
Anal Chem ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063515

RESUMO

In the last few decades, growing numbers of fluorescent probes have been developed to detect intracellular GSH. However, the majority of probes for GSH were irreversible without monitoring the changes of intracellular GSH concentration. Therefore, recently, fluorescent probes for monitoring concentrations of GSH in real-time in living cells have come into being to address this challenge. This Perspective aimed at the development of reversible probes for GSH was organized by structural features, chemical reactions, and physicochemical properties. The reversible probes designed by a coumarin skeleton as a read-out fluorophore and the Michael addition reaction as a response mechanism accounted for most of the reported reversible probes. The performances of reversible fluorescent probes based on Michael addition could be roughly predicted by fundamental laws of kinetics and thermodynamics in physical chemistry. Essentially, the design principles included a highly reactive site for GSH, a small thermodynamic driving force, a desirable Kd of 1-10 mM, and excellent cell membrane permeability. Prospectively, the development of various mechanisms and fluorophores will be effective measures to enrich the types of reversible probes for GSH.

15.
Int J Med Sci ; 17(16): 2594-2602, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33029102

RESUMO

Pulmonary hypertension (PH) is a lethal and rapidly progressing disorder if left untreated, but there is still no definitive therapy. An imbalance between vasoconstriction and vasodilation has been proposed as the mechanism underlying PH. Among the vasomediators of the pulmonary circulation is the renin-angiotensin system (RAS), the involvement of which in the development of PH has been proposed. Within the RAS, angiotensin-converting enzyme 2 (ACE2), which converts angiotensin (Ang) II into Ang-(1-7), is an important regulator of blood pressure, and has been implicated in cardiovascular disease and PH. In this study, we investigated the effects of the ACE2 activator diminazene aceturate (DIZE) on the development of PH secondary to left ventricular dysfunction. A model of PH secondary to left ventricular dysfunction was established in 6-week-old Wistar rats by ascending aortic banding for 42 days. The hemodynamics and pulmonary expression of ACE, Ang II, ACE2, Ang-(1-7), and the Ang-(1-7) MAS receptor were investigated in the early treatment group, which was administered DIZE (15 mg/kg/day) from days 1 to 42, and in the late treatment group, administered DIZE (15 mg/kg/day) from days 29 to 42. Sham-operated rats served as controls. DIZE ameliorated mean pulmonary artery pressure, pulmonary arteriolar remodeling, and plasma brain natriuretic peptide levels, in addition to reversing the overexpression of ACE and up-regulation of both Ang-(1-7) and MAS, in the early and late treatment groups. DIZE has therapeutic potential for preventing the development of PH secondary to left ventricular dysfunction through ACEII activation and the positive feedback of ANG-(1-7) on the MAS receptor. A translational study in humans is needed to substantiate these findings.

16.
Crit Pathw Cardiol ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33031192

RESUMO

PURPOSE: To understand the hemodynamic effect of angiotensin II as a vasopressor in patients with shock secondary to COVID-19 infection. METHODS: A retrospective analysis was performed on all patients at a single center with COVID-19 infection and shock who were treated with angiotensin II. The hemodynamic response to angiotensin II was estimated by recording the mean arterial pressure, norepinephrine equivalent dose (NED) and urine output. RESULTS: Ten patients with COVID-19 related shock were treated with angiotensin II. Over the initial 6 hours, the average the norepinephrine equivalent dose decreased by 30.4% (from 64.6 mcg/min to 44 mcg/min) without a significant change in the mean arterial pressure (0.7% decrease). Six patients experienced at least a 25% reduction in norepinephrine equivalent dose by 6 hours, and two experienced at least a 50% reduction. CONCLUSIONS: On average, the hemodynamic response to angiotensin II in COVID-19 related shock was favorable. Two patients had a marked rapid improvement. Given the relationship of SARS-CoV-2 with the renin angiotensin aldosterone system, further evaluation of angiotensin II for the treatment of COVID-19 related shock is warranted.

17.
J Nucl Cardiol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33034036

RESUMO

BACKGROUND: Acute psychological stressors such as anger can precipitate ventricular arrhythmias, but the mechanism is incompletely understood. Quantification of regional myocardial sympathetic activity with 123I-metaiodobenzylguanidine (123I-mIBG) SPECT imaging in conjunction with perfusion imaging during mental stress may identify a mismatch between perfusion and sympathetic activity that may exacerbate a mismatch between perfusion and sympathetic activity that could create a milieu of increased vulnerability to ventricular arrhythmia. METHODS: Five men with ischemic cardiomyopathy (ICM), and five age-matched healthy male controls underwent serial 123I-mIBG and 99mTc-Tetrofosmin SPECT/CT imaging during an anger recall mental stress task and dual isotope imaging was repeated approximately 1 week later during rest. Images were reconstructed using an iterative reconstruction algorithm with CT-based attenuation correction. The mismatch of left ventricular myocardial 123I-mIBG and 99mTc-Tetrofosmin was assessed along with radiotracer heterogeneity and the 123I-mIBG heart-to-mediastinal ratios (HMR) were calculated using custom software developed at Yale. RESULTS: The hemodynamic response to mental stress was similar in both groups. The resting-HMR was greater in healthy control subjects (3.67 ± 0.95) than those with ICM (3.18 ± 0.68, P = .04). Anger recall significantly decreased the HMR in ICM patients (2.62 ± 0.3, P = .04), but not in normal subjects. The heterogeneity of 123I-mIBG uptake in the myocardium was significantly increased in ICM patients during mental stress (26% ± 8.23% vs. rest: 19.62% ± 9.56%; P = .01), whereas the 99mTc-Tetrofosmin uptake pattern was unchanged. CONCLUSION: Mental stress decreased the 123I-mIBG HMR, increased mismatch between sympathetic activity and myocardial perfusion, and increased the heterogeneity of 123I-mIBG uptake in ICM patients, while there was no significant change in myocardial defect size or the heterogeneity of 99mTc-Tetrofosmin perfusion. The changes observed in this proof-of-concept study may provide valuable information about the trigger-substrate interaction and the potential vulnerability for ventricular arrhythmias.

18.
J Appl Toxicol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33029813

RESUMO

Mono(2-ethylhexyl)phthalate (MEHP), the active metabolite of di(2-ethylhexyl)phthalate (DEHP), is known to exert cardiotoxicity. The aim of the present study was to investigate the role of forkhead box O3a (FOXO3a) in MEHP-induced human AC16 cardiomyocyte injuries. MEHP reduced cell viability and mitochondrial membrane potential (ΔΨm), whereas it increased lactate dehydrogenase (LDH) leakage, production of reactive oxygen species (ROS), and apoptosis in cardiomyocytes. The expression of FOXO3a and its target genes, mitochondrial superoxide dismutase (Mn-SOD) and apoptosis repressor with caspase recruitment domain (ARC), increased after MEHP exposure, but the expression of p-FOXO3a protein was decreased. Overexpression of FOXO3a decreased the production of ROS and the apoptosis rate induced by MEHP, and the expression of Mn-SOD and ARC was further increased after MEHP exposure. In contrast, knockdown of FOXO3a resulted in increased ROS production and apoptosis and suppressed the expression of Mn-SOD and ARC in the presence of MEHP. However, overexpression or knockdown of FOXO3a did not affect MEHP-induced loss of ΔΨm. In conclusion, the loss of ΔΨm and apoptosis are involved in MEHP-induced cardiomyocyte toxicity. Activation of FOXO3a defends against MEHP-induced oxidative stress and apoptosis by upregulating the expression of Mn-SOD and ARC in AC16 cardiomyocytes.

19.
Lab Chip ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33030494

RESUMO

The mechanical properties of cell nuclei have been recognized to reflect and modulate important cell behaviors such as migration and cancer cell malignant tendency. However, these nuclear properties are difficult to characterize accurately using conventional measurement methods, which are often based on probing or deforming local sites over a nuclear region. The corresponding results are sensitive to the measurement position, and they are not decoupled from the cytoplasmic properties. Microfluidics is widely recognized as a promising technique for bioassay and phenotyping. In this report, we develop a simple and nondestructive approach for the single-cell quantification of nuclear elasticity based on microfluidics by considering different deformation levels of a live cell captured along a confining microchannel. We apply two inlet pressure levels to drive the flow of human nasopharyngeal epithelial cells (NP460) and human nasopharyngeal cancerous cells (NPC43) into the microchannels. A model considering the essential intracellular components (cytoplasm and nucleus) for describing the mechanics of a cell deforming along the confining microchannel is used to back-calculate the cytoplasmic and nuclear properties. On the other hand, we also apply a widely used chemical nucleus extraction technique to examine its possible effects (e.g., reduced nuclear modulus and reduced lamin A/C expression). To determine if the decoupled nuclear properties are representative of cancer-related attributes, we classify the NP460 and NPC43 cells using the decoupled physical properties as classification factors, resulting in an accuracy of 79.1% and a cell-type specificity exceeding 74%. It should be mentioned that the cells can be recollected at the device outlet after the nondestructive measurement. Hence, the reported cell elasticity measurement can be combined with downstream genetic and biochemical assays for general cell research and cancer diagnostic applications.

20.
J Sci Food Agric ; 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006396

RESUMO

BACKGROUND: Global food security faces a number of challenges due to increasing population, climate change, and urbanization, while excessive use of nitrogen fertilizers has become a major challenge for sustainable, intensive agriculture. Assessing the impact of agronomic management practices on seed yield, grain quality, and soil fertility is a critical step in understanding nutrientuse efficiency. RESULT: The comprehensive evaluation index had good fitness to that of single attribute (i.e. seed yield, crop quality and soil fertility), indicating that the comprehensive evaluation index was reliable. Applying controlled-release urea (rice in wheat and oilseed rape field: 150 kg N ha-1 , other crops: 120 kg N ha-1 ) plus common urea (30 kg N ha-1 ) incorporating straw from the previous season across the growing season for cereal and oilseed crops showed a slight improvement in seed productivity and Nuse efficiency among three cropping systems in the traditional evaluation method. Compared with local farm practice (applying common urea of 150 kg N ha-1 ), applying these practices in combination based on the outcome of the comprehensive evaluation index method decreased the seed yield by -1.27 ~ 29.8% but improved quality and soil fertility for the paddy-upland cropping system, respectively. CONCLUSION: Properly managing N application by applying partial and fully controlled release of urea with or without straw incorporation for a specific crop system has the potential to provide a better compromise among yield, grain quality, and soil fertility in southern China. © 2020 Society of Chemical Industry.

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