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1.
J Interv Cardiol ; 2024: 4512655, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38415185

RESUMO

Aims: To evaluate the impact of neutrophil-to-lymphocyte ratio (NLR) on periprocedural pulmonary hypertension (PH) and 3-month all-cause mortality in patients with aortic stenosis (AS) who underwent transcatheter aortic valve replacement (TAVR) and to develop a nomogram for predicting the mortality for these patients. Methods and Results: 124 patients undergoing TAVR were categorized into three groups according to systolic pulmonary artery pressure (sPAP): Group I (no PH, n = 61) consisted of patients with no pre- and post-TAVR PH; Group II (improved PH, n = 35) consisted of patients with post-TAVR systolic pulmonary artery pressure (sPAP) decreased by more than 10 mmHg compared to pre-TAVR levels; and Group III (persistent PH, n = 28) consisted of patients with post-TAVR sPAP no decrease or less than 10 mmHg, or new-onset PH after the TAVR procedure. The risk of all-cause mortality within 3 months tended to be higher in Group II (11.4%) and Group III (14.3%) compared to Group I (3.3%) (P=0.057). The multinomial logistic regression analysis demonstrated a positive correlation between NLR and both improved PH (OR: 1.182, 95% CI: 1.036-1.350, P=0.013) and persistent PH (OR: 1.181, 95% CI: 1.032-1.352, P=0.016). Kaplan-Meier analysis revealed a significant association between higher NLR and increased 3-month all-cause mortality (16.1% vs. 3.1% in lower NLR group, P=0.021). The multivariable Cox regression analysis confirmed that NLR was an independent predictor for all-cause mortality within 3 months, even after adjusting for clinical confounders. A nomogram incorporating five factors (BNP, heart rate, serum total bilirubin, NLR, and comorbidity with coronary heart disease) was developed. ROC analysis was performed to discriminate the ability of the nomogram, and the AUC was 0.926 (95% CI: 0.850-1.000, P < 0.001). Conclusions: Patients with higher baseline NLR were found to be at an increased risk of periprocedural PH and all-cause mortality within 3 months after TAVR.


Assuntos
Estenose da Valva Aórtica , Hipertensão Pulmonar , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Hipertensão Pulmonar/etiologia , Neutrófilos , Fatores de Risco , Linfócitos , Resultado do Tratamento , Valva Aórtica/cirurgia , Índice de Gravidade de Doença , Estudos Retrospectivos
2.
J Sci Food Agric ; 104(5): 2792-2797, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38010608

RESUMO

BACKGROUND: Agarose, mainly composed of 3,6-anhydro-α-l-galactopyranose (LA) and ß-d-galactopyranose (G) units, is an important polysaccharide with wide applications in food, biomedical and bioengineering industries. Carbohydrate-binding modules (CBMs) are favorable tools for the investigations of polysaccharides. Few agarose-binding CBMs have been hitherto reported, and their binding specificity is unclear. RESULTS: An unknown domain with a predicted ß-sandwich fold was discovered from a ß-agarase of the marine bacterium Wenyingzhuangia fucanilytica CZ1127T . The expressed protein WfCBM101 could bind to agarose and exhibited relatively weak affinity for porphyran, with no affinity for the other seven examined polysaccharides. The protein binds to the tetrasaccharide (LA-G)2 , but not to the major tetrasaccharide contained in porphyran. The sequence novelty and well-defined binding function of WfCBM101 shed light on a novel CBM family (CBM101). Furthermore, the feasibility of WfCBM101 for visualizing agarose in situ was confirmed. CONCLUSION: A novel CBM, WfCBM101, with a desired specificity for agarose was discovered and characterized, which represents a new CBM family. The CBM could be utilized as a promising tool for studies of agarose. © 2023 Society of Chemical Industry.


Assuntos
Galactose , Polissacarídeos , Sefarose , Polissacarídeos/química , Oligossacarídeos
3.
Am J Physiol Endocrinol Metab ; 323(1): E69-E79, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35575231

RESUMO

Brown adipose tissue (BAT) is the primary site of adaptive thermogenesis, which is involved in energy expenditure and has received much attention in the field of obesity treatment. By screening a small-molecule compound library of drugs approved by the Food and Drug Administration, pantothenic acid was identified as being able to significantly upregulate the expression of uncoupling protein 1 (UCP1), a key thermogenic protein found in BAT. Pantothenate (PA) treatment decreased adiposity, reversed hepatic steatosis, and improved glucose homeostasis by increasing energy expenditure in C57BL/6J mice fed a high-fat diet. PA also significantly increased BAT activity and induced beige adipocytes formation. Mechanistically, the beneficial effects were mediated by UCP1 because PA treatment was unable to ameliorate obesity in UCP1 knockout mice. In conclusion, we identified PA as an effective BAT activator that can prevent obesity and may represent a promising strategy for the clinical treatment of obesity and related metabolic diseases.NEW & NOTEWORTHY PA treatment effectively and safely protected against obesity via the BAT-UCP1 axis. PA has therapeutic potential for treating obesity and type II diabetes.


Assuntos
Tecido Adiposo Marrom , Diabetes Mellitus Tipo 2 , Tecido Adiposo Marrom/metabolismo , Animais , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Termogênese , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
4.
J Hepatol ; 77(3): 619-631, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35452693

RESUMO

BACKGROUND & AIMS: Vacuole membrane protein 1 (VMP1) is an endoplasmic reticulum (ER) transmembrane protein that regulates the formation of autophagosomes and lipid droplets. Recent evidence suggests that VMP1 plays a critical role in lipoprotein secretion in zebra fish and cultured cells. However, the pathophysiological roles and mechanisms by which VMP1 regulates lipoprotein secretion and lipid accumulation in non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are unknown. METHODS: Liver-specific and hepatocyte-specific Vmp1 knockout mice as well as Vmp1 knock-in mice were generated by crossing Vmp1flox or Vmp1KI mice with albumin-Cre mice or by injecting AAV8-TBG-cre, respectively. Lipid and energy metabolism in these mice were characterized by metabolomic and transcriptome analyses. Mice with hepatic overexpression of VMP1 who were fed a NASH diet were also characterized. RESULTS: Hepatocyte-specific deletion of Vmp1 severely impaired VLDL secretion resulting in massive hepatic steatosis, hepatocyte death, inflammation and fibrosis, which are hallmarks of NASH. Mechanistically, loss of Vmp1 led to decreased hepatic levels of phosphatidylcholine and phosphatidylethanolamine as well as to changes in phospholipid composition. Deletion of Vmp1 in mouse liver also led to the accumulation of neutral lipids in the ER bilayer and impaired mitochondrial beta-oxidation. Overexpression of VMP1 ameliorated steatosis in diet-induced NASH by improving VLDL secretion. Importantly, we also showed that decreased liver VMP1 is associated with NAFLD/NASH in humans. CONCLUSIONS: Our results provide novel insights on the role of VMP1 in regulating hepatic phospholipid synthesis and lipoprotein secretion in the pathogenesis of NAFLD/NASH. LAY SUMMARY: Non-alcoholic fatty liver disease and its more severe form, non-alcoholic steatohepatitis, are associated with a build-up of fat in the liver (steatosis). However, the exact mechanisms that underly steatosis in patients are not completely understood. Herein, the authors identified that the lack of a protein called VMP1 impairs the secretion and metabolism of fats in the liver and could therefore contribute to the development and progression of non-alcoholic fatty liver disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Lipoproteínas/metabolismo , Fígado/patologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fosfolipídeos/metabolismo
5.
Plant Cell Rep ; 41(1): 233-248, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34713321

RESUMO

KEY MESSAGE: An SVP protein, PhSVP, bound to the CArG-boxes in the promoter regions of FT-like paralogs and repressed their expression, thus affecting the floral transition in Phalaenopsis orchid. Phalaenopsis is an important ornamental flower native to tropical rain forests. It usually reaches vegetative maturity after 4-5 leaves and, after a juvenile stage, forms a flower spike (inflorescence) from the axillary buds. The PEBP gene family encodes a phosphatidyl-ethanolamine-binding protein (PEBP) domain involved in regulating flowering and other aspects of plant development. Here, we identified eight PEBP family genes in Phalaenopsis and detected the expression patterns of seven of them in various organs. Among them, PhFT1 (Phalaenopsis hybrid FLOWERING LOCUS T1), PhFT3, PhFT5, and PhMFT (Phalaenopsis hybrid MOTHER OF FT AND TFL1) promoted flowering in transgenic Arabidopsis, while PhFT6 inhibited flowering. PhSVP (Phalaenopsis hybrid SHORT VEGETATIVE PHASE), an SVP protein that repressed flowering in Arabidopsis, bound to the CArG-boxes in the promoter regions of PhFT3, PhFT6, and PhMFT in a yeast one-hybrid assay. Additionally, dual-luciferase and transient expression assays showed that PhSVP significantly inhibits the expression of both PhFT3 and PhFT6. Together, our work provides a comprehensive understanding of the PhFT-like genes that can promote or repress flowering, and it suggests strategies for regulating the floral transition in Phalaenopsis that exploit the evolutionary versatility of PhFTs to respond to various signals stimuli.


Assuntos
Flores/crescimento & desenvolvimento , Orchidaceae/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Flores/genética , Orchidaceae/crescimento & desenvolvimento , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Alinhamento de Sequência , Fatores de Transcrição/metabolismo
6.
Nano Lett ; 21(1): 778-784, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33301328

RESUMO

Reprogrammed glucose metabolism is vital for cancer cells, but aspartate, an intermediate metabolic product, is the limiting factor for cancer cell proliferation. However, due to the complexity of metabolic pathways, it remains unclear whether glucose is the primary source of endogenous aspartate. Here, we report the design of an innovative molecular deactivator, based on a multifunctional upconversion nanoprobe, to explore the link between glucose and aspartate. This molecular deactivator mainly works in the acidic, hypoxic tumor microenvironment and deactivates multiple types of glucose transporters on cancer cell membranes upon illumination at 980 nm. Cancer cell proliferation in vivo is strongly inhibited by blocking glucose transporters. Our experimental data confirm that the cellular synthesis of aspartate for tumor growth is glucose-dependent. This work also demonstrates the untapped potential of molecularly engineered upconversion nanoprobes for discovering hidden metabolic pathways and improving therapeutic efficacy of conventional antitumor drugs.


Assuntos
Antineoplásicos , Neoplasias , Antineoplásicos/uso terapêutico , Ácido Aspártico/farmacologia , Proliferação de Células/genética , Glucose , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Microambiente Tumoral
7.
Appl Microbiol Biotechnol ; 105(14-15): 6007-6018, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34390354

RESUMO

Liver fibrosis is caused by the accumulation of extracellular matrix proteins on the surface of hepatocytes and results from chronic liver injury. TGFß1 is one of the most important promoters of hepatic fibrosis, which accelerates the transformation of hepatic stellate cells to myofibroblasts and collagen expression. It is well-known that TGFß1 binds to TGFßR2 to mediate its downstream signal cascades to regulate target gene transcription. Therefore, the TGFßR2 blocker might be a prominent drug candidate. We constructed TGFßR2 extracellular domain into living biotherapeutics Lactococcus lactis to reduce hepatic fibrosis in CCl4 treated mice in the present study. We found that the culture supernatant of the recombinant bacteria can inhibit the TGFß1-induced collagen synthesis in the hepatic stellate cells at the cellular level. In addition, results of in vivo study showed that the recombinant bacteria significantly reduced the degree of liver fibrosis in CCl4-treated mice. Furthermore, flow cytometry results indicated that the recombinant bacteria treatment significantly reduced the CD11b+ Kupffer cells compared with the empty vector bacteria group. Consistently, fibrosis-related gene and protein expression were significantly reduced upon recombinant bacteria treatment. Finally, the subchronic toxicity test results showed that this bacteria strain did not have any significant side effects. In conclusion, our recombinant Lactococcus lactis shows tremendous therapeutic potential in liver fibrosis. KEY POINTS: • The supernatant of L. lactis expressing TGFßR2 inhibits the activation of myofibroblast. • The oral recombinant strain reduced the degree of liver fibrosis and inflammation in mice. • The recombinant strain was safe in subchronic toxicity test in mice.


Assuntos
Lactococcus lactis , Animais , Colágeno , Hepatócitos , Lactococcus lactis/genética , Cirrose Hepática/prevenção & controle , Camundongos
8.
Sensors (Basel) ; 21(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577337

RESUMO

In this paper, a novel D-shaped photonic crystal fiber sensor for simultaneous measurements of magnetic field and temperature is proposed and characterized. Based on the surface plasmon resonance theory, the D-shaped flat surface coated with a gold layer is in direct contact with magnetic fluid to detect magnetic field, and one of the relatively small air holes near the fiber core is filled with polydimethylsiloxane (PDMS) to sense temperature. The realization of measuring the magnetic field and temperature separately through two channels depends on the fact that the magnetic field only changes the refractive index of the magnetic fluid, but has no effect on the refractive index of PDMS. The refractive index of the magnetic fluid and PDMS can be affected by temperature at the same time. The sensor designed in this work can separate the variations of the magnetic field and temperature simultaneously, therefore solving the cross-sensitivity problem to further improve the magnetic field sensitivity. When the thickness of the gold film is 50 nm and the radius of the filling hole is 0.52 µm, the magnetic field sensitivity and the temperature sensitivity of magnetic field sensor based on temperature self-reference can reach 0.14274 nm/Oe and -0.229 nm/°C, respectively.

9.
J Dairy Sci ; 103(5): 3924-3936, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32113776

RESUMO

This study sought to assess the cholesterol-lowering activity of peptides obtained from milk casein hydrolyzed with neutrase. The bioactive peptides were separated using a Sephadex G-10 chromatographic column (Amersham Pharmacia Biotech, Uppsala, Sweden) after ultrafiltration using a 1-kDa molecular mass cutoff membrane. Via ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry, we determined that peptides Thr-Asp-Val-Glu-Asn [TDVEN; ß-casein f(143-147)], Leu-Gln-Pro-Glu [LQPE; ß-casein f(103-106)], Val-Ala-Pro-Phe-Pro-Glu [VAPFPE; αS1-casein f(40-45)], and Val-Leu-Pro-Val-Pro-Gln [VLPVPQ ß-casein f(185-190)] reduced micellar cholesterol solubility. After Caco-2 cells were treated with LQPE, VLPVPQ, and VAPFPE, the Niemann-Pick C1-Like 1 (NPC1L1) protein levels decreased by (means ± SEM) 19.33 ± 2.47%, 52.1 ± 3.77%, and 23.09 ± 8.52%, respectively, compared with the control group. Treatment with each peptide induced significant upregulation of ATP binding cassette subfamily G member 8 antibody (ABCG8) mRNA expression by 398.1 ± 23.27%, 86.4 ± 27.07%, and 92.8 ± 8.49%. We found that VLPVPQ and LQPE significantly upregulated ATP-binding cassette transporter A1 (ABCA1) transcription by 203.9 ± 8.44% and 220.8 ± 36.42% respectively, whereas VLPVPQ significantly decreased mRNA expression of acetyl-CoA-acetyltransferase 2 (ACAT2) and microsomal triacylglycerols (MTP). The cholesterol-lowering action of milk-derived peptides may be induced by suppression of micellar cholesterol solubility and affects the expression of cholesterol absorption-related proteins and enzymes in intestinal epithelial cells. This research discovers new milk-derived peptides with decreasing cholesterol micellar solubility and provides a theoretical basis of in vitro cholesterol-lowering effects of peptides.


Assuntos
Caseínas/metabolismo , Colesterol/metabolismo , Absorção Intestinal/efeitos dos fármacos , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Células CACO-2 , Humanos , Micelas , Leite/metabolismo , Peptídeos/metabolismo , Solubilidade
10.
J Nanosci Nanotechnol ; 19(6): 3643-3646, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30744799

RESUMO

We report on fabricating plasmonic nanorod crystals using focused ion beam lithography. We first demonstrate manipulating the profiles of nanorods perpendicularly aligned with the substrate. Then we show accurate control of nanorod outlines can be achieved. We also show that it is feasible to manufacture nanorods obliquely aligned with the substrate. Tunable plasmon resonance can be realized with different tilting angles and geometries. Our approach may find important applications in plasmon-assisted sensing and surface enhanced spectroscopy.

11.
J Dairy Sci ; 102(2): 961-975, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30594363

RESUMO

Lactobacillus helveticus LB 10 proteinases immobilized with sodium alginate were used to hydrolyze whey protein to produce angiotensin-I-converting enzyme (ACE)-inhibitory peptides. The generated hydrolysates were tested for ACE-inhibitory activity and for their ability to be transported across Caco-2 cell monolayers. Using a response surface method, we determined that a proteinase concentration of 7.55 mg/mL, sodium alginate concentration of 2.03 g/100 mL, and glutaraldehyde concentration of 0.39% were found to be the optimal immobilization conditions. Compared with free proteinase, the immobilized proteinase had significantly higher pH, thermal and storage stability, and reusability. Whey protein hydrolysates were fractionated by gel filtration chromatography and ACE-inhibitory peptide mixtures were transported across Caco-2 cell monolayers in a human intestinal-absorption model. The di- and tripeptides KA, EN, DIS, EVD, LF, AIV, and VFK (half-maximal inhibitory concentrations (mean ± standard deviation) of 1.24 ± 0.01, 1.43 ± 0.04, 1.59 ± 0.27, 1.32 ± 0.05, 1.60 ± 0.39, 2.66 ± 0.02, and 1.76 ± 0.09 mmol/L, respectively) were detected on the basolateral side of the Caco-2 cell monolayer using ultra-performance liquid chromatography-tandem mass spectrometry. These results highlight that ACE-inhibitory peptides are present on the basolateral side of the Caco-2 cell model after transportation of whey protein hydrolysate across the Caco-2 cell membrane.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/metabolismo , Enzimas Imobilizadas/metabolismo , Lactobacillus helveticus/enzimologia , Peptídeo Hidrolases/metabolismo , Proteínas do Soro do Leite/metabolismo , Animais , Transporte Biológico , Células CACO-2 , Membrana Celular/metabolismo , Humanos , Hidrólise , Peptidil Dipeptidase A/metabolismo , Proteólise
12.
J Adv Nurs ; 75(11): 3088-3096, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31225645

RESUMO

AIM: To present a study protocol for evaluating the feasibility and effectiveness of an individual face-to-face intervention based on protective factors to improve resilience among breast cancer patients. BACKGROUND: Research involving the effectiveness of universal interventions to improve resilience for breast cancer patients has seldom been reported and there is an urgent need to find a more acceptable, cost-effective method of providing emotional support. Through health education and psychological interventions, increasing protective factors could promote recovery to the original condition and improve resilience. DESIGN: A randomized controlled trial of an individual face-to-face intervention. METHODS: A total of 160 adults diagnosed with confirmed breast cancer will be recruited. The patients will be randomly assigned to the control group (N = 80) or the intervention group (N = 80). An intervention focusing on protective factors will be implemented in the intervention group. A survey of the patients from the two groups will be conducted at baseline, 1, 3, 6, and 12 months. The primary outcome is resilience, measured by the 14-item Resilience Scale. Secondary outcomes include self-efficacy, optimism, perceived social support, and mastery. The Chinese versions of the General Self-Efficacy Scale, revised Life Orientation Test, Multidimensional Scale of Perceived Social Support, and Self-Mastery Scale will be used to measure the four protective factors. IMPACT: One-to-one and face-to-face interventions have many potential advantages for inpatients, including convenience, accessibility and individuality. Once its effectiveness is confirmed, the intervention will be implemented broadly and make support available for a large number of patients.


Assuntos
Povo Asiático/psicologia , Neoplasias da Mama/psicologia , Aconselhamento/normas , Fatores de Proteção , Qualidade de Vida/psicologia , Resiliência Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/estatística & dados numéricos , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos e Questionários
13.
J Adv Nurs ; 75(8): 1805-1814, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31037755

RESUMO

AIM: To describe a protocol that examines the feasibility and effectiveness of a face-to-face guided self-disclosure intervention for facilitating benefit finding and other related psychological outcomes for breast cancer patients. BACKGROUND: Benefit finding can promote a positive attitude among patients facing disease. However, limited studies have focused on improving benefit finding among breast cancer patients. Previous research has been based on group interventions, which may not suit all patients. Self-disclosure was recognized as a strong predictor of benefit finding. This protocol is based on a brief face-to-face disclosure intervention to improve benefit finding for breast cancer patients. DESIGN: A non-blinded randomized controlled trial. METHODS: A total of 154 patients with breast cancer who have undergone radical mastectomy will be randomly assigned to either the experimental group, which will participate in a six-session face-to-face individual intervention, or the control group at a ratio of 1:1. Baseline assessments will take place after the breast cancer diagnosis, with follow-up assessments at 3, 6 and 9 months after baseline. The primary outcome is benefit finding; other outcomes are self-disclosure, cognitive reappraisal, social support, optimism and medical coping modes. DISCUSSION: This study is to design a protocol for guided self-disclosure interventions to promote benefit finding in Chinese breast cancer patients. If this intervention is feasible and effective, it could be implemented in clinical practice. IMPACT: This study will provide useful advice for health professionals to guide breast cancer patients in benefit finding during stressful events. If it is effective, it will be implemented broadly in clinical practice.


Assuntos
Adaptação Psicológica , Povo Asiático/psicologia , Neoplasias da Mama/psicologia , Revelação , Sobreviventes/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
14.
Int J Mol Sci ; 20(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939798

RESUMO

Brown adipose tissue (BAT), an organ that burns energy through uncoupling thermogenesis, is a promising therapeutic target for obesity. However, there are still no safe anti-obesity drugs that target BAT in the market. In the current study, we performed large scale screening of 636 compounds which were approved by Food and Drug Administration (FDA) to find drugs that could significantly increase uncoupling protein 1 (UCP1) mRNA expression by real-time PCR. Among those UCP1 activators, most of them were antibiotics or carcinogenic compounds. We paid particular attention to fluvastatin sodium (FS), because as an inhibitor of the cellular hydroxymethyl glutaryl coenzyme A (HMG-CoA) reductase, FS has already been approved for treatment of hypercholesteremia. We found that in the cellular levels, FS treatment significantly increased UCP1 expression and BAT activity in human brown adipocytes. Consistently, the expression of oxidative phosphorylation-related genes was significantly increased upon FS treatment without differences in adipogenic gene expression. Furthermore, FS treatment resisted to high-fat diet (HFD)-induced body weight gain by activating BAT in the mice model. In addition, administration of FS significantly increased energy expenditure, improved glucose homeostasis and ameliorated hepatic steatosis. Furthermore, we reveal that FS induced browning in subcutaneous white adipose tissue (sWAT) known to have a beneficial effect on energy metabolism. Taken together, our results clearly demonstrate that as an effective BAT activator, FS may have great potential for treatment of obesity and related metabolic disorders.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Fármacos Antiobesidade/uso terapêutico , Fluvastatina/uso terapêutico , Obesidade/tratamento farmacológico , Tecido Adiposo Marrom/metabolismo , Animais , Fármacos Antiobesidade/farmacologia , Células Cultivadas , Metabolismo Energético , Fluvastatina/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
15.
Molecules ; 24(13)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277470

RESUMO

In recent years, the development of metamaterials and metasurfaces has drawn great attention, enabling many important practical applications. Focusing and lensing components are of extreme importance because of their significant potential practical applications in biological imaging, display, and nanolithography fabrication. Metafocusing devices using ultrathin structures (also known as metasurfaces) with superlensing performance are key building blocks for developing integrated optical components with ultrasmall dimensions. In this article, we review the metamaterial superlensing devices working in transmission mode from the perfect lens to two-dimensional metasurfaces and present their working principles. Then we summarize important practical applications of metasurfaces, such as plasmonic lithography, holography, and imaging. Different typical designs and their focusing performance are also discussed in detail.


Assuntos
Lentes , Nanotecnologia , Óptica e Fotônica , Prata/química , Propriedades de Superfície
16.
Molecules ; 24(14)2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31336634

RESUMO

Metamaterials are "new materials" with different superior physical properties, which have generated great interest and become popular in scientific research. Various designs and functional devices using metamaterials have formed a new academic world. The application concept of metamaterial is based on designing diverse physical structures that can break through the limitations of traditional optical materials and composites to achieve extraordinary material functions. Therefore, metadevices have been widely studied by the academic community recently. Using the properties of metamaterials, many functional metadevices have been well investigated and further optimized. In this article, different metamaterial structures with varying functions are reviewed, and their working mechanisms and applications are summarized, which are near-field energy transfer devices, metamaterial mirrors, metamaterial biosensors, and quantum-cascade detectors. The development of metamaterials indicates that new materials will become an important breakthrough point and building blocks for new research domains, and therefore they will trigger more practical and wide applications in the future.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Transferência de Energia , Modelos Teóricos
17.
Cancer Sci ; 109(10): 3272-3284, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30039622

RESUMO

Acetylation plays an important role in regulating the chaperone activity of heat shock protein 90 (Hsp90) during malignant transformation through the stabilization and conformational maturation of oncogenic proteins. However, the functional acetylation sites, potential anticancer drug targets, are still emerging. We found that acetylation at K292 in Hsp90α is critical for the development and treatment of breast cancer. Acetylation at K292 not only augments the affinity of Hsp90 to ATP, cochaperones, and client proteins but it also promotes cancer cell colony formation, migration, and invasion in vitro as well as tumor growth in vivo. Importantly, K292-acetylated Hsp90 has been validated as an exciting anticancer drug target by interfering with the complex formation between K292-acetylated Hsp90 and cochaperone Cdc37, leading to diminishment of kinase client maturation and proteasome-dependent degradation of kinase substrates. Furthermore, we showed that simvastatin prevented, whereas LBH589 promoted, the progression of Hsp90 chaperone cycling and client maturation, resulting in an increment of cell apoptosis by the combination of simvastatin and LBH589 in a mouse xenograft model. These data suggest that simvastatin is a novel Hsp90 inhibitor to disrupt the formation of the K292-acetylated Hsp90/Cdc37 complex in triple-negative breast cancer cells. The combination of simvastatin with LBH589 could be used as a novel therapeutic strategy for triple-negative breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas de Ciclo Celular/metabolismo , Chaperoninas/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sinvastatina/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Acetilação/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Indóis/farmacologia , Indóis/uso terapêutico , Lisina/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Panobinostat , Ligação Proteica/efeitos dos fármacos , Sinvastatina/uso terapêutico , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Biochem Biophys Res Commun ; 501(3): 807-813, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29775611

RESUMO

The strong effects of classic brown adipose tissue (BAT) and recruited beige adipocytes in treatment of obesity and metabolic syndrome have been attracting increasing research interest. Cold treatment is an effective, convenient approach to stimulate BAT activity and induce white adipose tissue (WAT) browning. Here, we utilized prolonged cold exposure (from 2 h to 2 weeks in a 4° cold chamber) to elucidate dynamic changes in BAT and in WAT browning during acute and chronic cold exposure in mice. BAT mass decreased quickly, with reduced lipid droplet sizes within 8 h of cold exposure owing to the utilization of BAT pre-storage triglycerides, and subsequently increased during prolonged cold exposure. These dynamic morphological changes in BAT were confirmed by gene expression changes in ADRB3 and PGC1α, while UCP1 and ELOVL3 expression was continuously up-regulated throughout the entire cold exposure period. Additionally, cold treatment increased BAT secretion of FGF21, which has been reported to activate beige adipocyte formation. Thus, to illustrate potential crosstalk between secreted BAT proteins (so-called BATokines) and beige adipogenesis during cold stress, we performed an interscapular BAT (iBAT) removal experiment in mice. Surprisingly, loss of classic iBAT enhanced WAT browning due to compensatorily increased sympathetic WAT input. Unexpectedly, we observed significantly reduced adiposity in the iBAT removal group compared with the control group. These results further suggest that WAT browning plays an important role in whole-body energy metabolism during cold acclimation, even without iBAT. Furthermore, our data imply that enhanced WAT browning may be an efficient therapeutic tool to combat obesity and related syndromes.


Assuntos
Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/fisiologia , Adiposidade , Resposta ao Choque Frio , Tecido Adiposo Marrom/cirurgia , Animais , Metabolismo Energético , Masculino , Camundongos Endogâmicos C57BL , Obesidade/terapia , Termogênese , Transcriptoma
19.
Anal Chem ; 89(3): 1838-1845, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28208265

RESUMO

In the work, we showed that the use of nanoemitters (tip dimension <1 µm, typically ∼100 nm) could dramatically reduce the nonspecific metal adduction to peptide or protein ions as well as improve the matrix tolerance of electrospray ionization mass spectrometry (ESI-MS). The proton-enriched smaller initial droplets are supposed to have played a significant role in suppressing the formation of metal adduct ions in nanoemitters. The proton-enrichment effect in the nanoemitters is related to both the exclusion-enrichment effect (EEE) and the ion concentration polarization effect (ICP effect), which permit the molecular ions to be regulated to protonated ones. Smaller initial charged droplets generated from nanoemitters need less fission steps to release the gas-phase ions; thus, the enrichment effect of salt was not as significant as that of microemitters (tip dimension >1 µm), resulting in the disappearing of salt cluster peaks in high mass-to-charge (m/z) region. The use of nanoemitters demonstrates a novel method for tuning the distribution of the metal-adducted ions to be in a controlled manner. This method is also characterized by ease of use and high efficiency in eliminating the formation of adduct ions, and no pretreatment such as desalting is needed even in the presence of salt at millimole concentration.

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