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1.
BMC Geriatr ; 24(1): 578, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965468

RESUMO

OBJECTIVE: We aimed to investigate the impact of sarcopenia and sarcopenic obesity (SO) on the clinical outcome in older patients with COVID-19 infection and chronic disease. METHODS: We prospectively collected data from patients admitted to Huadong Hospital for COVID-19 infection between November 1, 2022, and January 31, 2023. These patients were included from a previously established comprehensive geriatric assessment (CGA) cohort. We collected information on their pre-admission condition regarding sarcopenia, SO, and malnutrition, as well as their medical treatment. The primary endpoint was the incidence of intubation, while secondary endpoints included in-hospital mortality rates. We then utilized Kaplan-Meier (K-M) survival curves and the log-rank tests to compare the clinical outcomes related to intubation or death, assessing the impact of sarcopenia and SO on patient clinical outcomes. RESULTS: A total of 113 patients (age 89.6 ± 7.0 years) were included in the study. Among them, 51 patients had sarcopenia and 39 had SO prior to hospitalization. Intubation was required for 6 patients without sarcopenia (9.7%) and for 18 sarcopenia patients (35.3%), with 16 of these being SO patients (41%). Mortality occurred in 2 patients without sarcopenia (3.3%) and in 13 sarcopenia patients (25.5%), of which 11 were SO patients (28%). Upon further analysis, patients with SO exhibited significantly elevated risks for both intubation (Hazard Ratio [HR] 7.43, 95% Confidence Interval [CI] 1.26-43.90, P < 0.001) and mortality (HR 6.54, 95% CI 1.09-39.38, P < 0.001) after adjusting for confounding factors. CONCLUSIONS: The prevalence of sarcopenia or SO was high among senior inpatients, and both conditions were found to have a significant negative impact on the clinical outcomes of COVID-19 infection. Therefore, it is essential to regularly assess and intervene in these conditions at the earliest stage possible.


Assuntos
COVID-19 , Mortalidade Hospitalar , Obesidade , Sarcopenia , Humanos , Sarcopenia/epidemiologia , Sarcopenia/terapia , COVID-19/epidemiologia , COVID-19/terapia , COVID-19/complicações , COVID-19/mortalidade , Masculino , Feminino , Idoso de 80 Anos ou mais , Estudos Prospectivos , Obesidade/epidemiologia , Obesidade/terapia , Obesidade/complicações , Mortalidade Hospitalar/tendências , Idoso , Avaliação Geriátrica/métodos , Hospitalização/tendências , SARS-CoV-2
2.
Opt Express ; 31(11): 17389-17407, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381475

RESUMO

Titanium nitride (TiN) is a complementary metal-oxide-semiconductor (CMOS) compatible material with large potential for the fabrication of plasmonic structures suited for device integration. However, the comparatively large optical losses can be detrimental for application. This work reports a CMOS compatible TiN nanohole array (NHA) on top of a multilayer stack for potential use in integrated refractive index sensing with high sensitivities at wavelengths between 800 and 1500 nm. The stack, consisting of the TiN NHA on a silicon dioxide (SiO2) layer with Si as substrate (TiN NHA/SiO2/Si), is prepared using an industrial CMOS compatible process. The TiN NHA/SiO2/Si shows Fano resonances in reflectance spectra under oblique excitation, which are well reproduced by simulation using both finite difference time domain (FDTD) and rigorous coupled-wave analysis (RCWA) methods. The sensitivities derived from spectroscopic characterizations increase with the increasing incident angle and match well with the simulated sensitivities. Our systematic simulation-based investigation of the sensitivity of the TiN NHA/SiO2/Si stack under varied conditions reveals that very large sensitivities up to 2305 nm per refractive index unit (nm RIU-1) are predicted when the refractive index of superstrate is similar to that of the SiO2 layer. We analyze in detail how the interplay between plasmonic and photonic resonances such as surface plasmon polaritons (SPPs), localized surface plasmon resonances (LSPRs), Rayleigh Anomalies (RAs), and photonic microcavity modes (Fabry-Pérot resonances) contributes to this result. This work not only reveals the tunability of TiN nanostructures for plasmonic applications but also paves the way to explore efficient devices for sensing in broad conditions.

3.
Eur J Clin Invest ; 52(2): e13714, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34800290

RESUMO

BACKGROUND: The prognosis of primary bile cholangitis (PBC) is linked to gut microbiota dysbiosis. This study investigated the association between the gut microbiome and elevated total bilirubin (TB) level in PBC patients treated with ursodeoxycholic acid (UCDA). METHODS: A total of 47 PBC patients with 12 months of UCDA treatment were enrolled. Patients were divided into the TB (+) (TB>1× upper limit of the normal range [ULN]; n = 20) and TB(-) (TB≤1× ULN; n = 27) groups. Stool and serum specimens were collected, and microbiota composition and functional characteristics in the 2 groups were evaluated by 16S RNA gene sequencing and bioinformatic analysis. RESULTS: Bacterial diversity was lower in the TB(+) group than in the TB(-) group, although there was no significant difference in bacterial community profile. The phylum Saccharibacteria showed differential abundance in the 2 groups. Meanwhile, the TB(-) group had lower abundance of the Gemmiger, Blautia, Anaerostipes and Coprococcus genera than the TB(+) group, whereas Holdemania was absent. The abundance of Gemmiger formicillis and Coprococcus eutactus was positively correlated with that of Faecalibacterium prausnitzii, while Blautia, Anaerostipes and Coprococcus were negatively correlated with total bile acid level. CONCLUSION: TB level in PBC patients treated for 12 months with UCDA is associated with a distinct gut microbiome profile.


Assuntos
Bilirrubina/sangue , Colagogos e Coleréticos/uso terapêutico , Microbioma Gastrointestinal , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/tratamento farmacológico , Cirrose Hepática Biliar/microbiologia , Ácido Ursodesoxicólico/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
4.
Metab Brain Dis ; 35(6): 869-881, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32495311

RESUMO

Minimal hepatic encephalopathy (MHE), which shows mild cognitive impairment, is a subtle complication of cirrhosis that has been shown to affect daily functioning and quality of life. However, until 2014, relevant guidelines do not give much attention to the diagnosis and treatment of MHE, resulting in patients being ignored and denied the benefits of treatment. In this review, we summarize recent cognition-based research about (1) alteration of nerve cells, including astrocytes, microglial cells and neurons, in mild cognitive impairment in MHE; (2) comparison of methods in detecting cognitive impairment in MHE; and (3) comparison of methods for therapy of cognitive impairment in MHE. We hope to provide information about diagnosis and treatment of cognitive impairment in patients with MHE.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/terapia , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/terapia , Psicometria/métodos , Astrócitos/patologia , Disfunção Cognitiva/psicologia , Encefalopatia Hepática/psicologia , Humanos , Microglia/patologia , Neurônios/patologia , Psicometria/tendências , Teste de Stroop , Resultado do Tratamento
5.
J Cell Physiol ; 234(12): 21588-21600, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31093975

RESUMO

Tumors tend to metastasize to the liver. Premetastatic niche formation is a vital step in liver metastasis. Tumor-derived exosomes can influence premetastatic niche formation from three aspects: vascular leakiness and angiogenesis, recruitment of nonresident cells, and changes in local resident cells. Exosomes from other tissues, such as mesenchymal stem cell-derived exosomes and engineered exosomes, also have therapeutic potential, but further research on these exosomes is required. Based on the mechanism of premetastatic niche formation, we summarize the therapeutic and diagnostic potential of exosomes in inhibiting liver metastases in this review in an attempt to provide new avenues for the prevention and treatment of liver metastases.


Assuntos
Exossomos/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Animais , Humanos , Microambiente Tumoral/genética
6.
J Appl Toxicol ; 39(1): 146-162, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30182494

RESUMO

Many categories of drugs can induce hepatotoxicity, so improving the prediction of toxic drugs is important. In vitro models using human hepatocytes are more accurate than in vivo animal models. Good in vitro models require an abundance of metabolic enzyme activities and normal cellular polarity. However, none of the in vitro models can completely simulate hepatocytes in the human body. There are two ways to overcome this limitation: enhancing the metabolic function of hepatocytes and changing the cultural environment. In this review, we summarize the current state of research, including the main characteristics of in vitro models and their limitations, as well as improved technology and developmental prospects. We hope that this review provides some new ideas for hepatotoxicity research.


Assuntos
Pesquisa Biomédica/métodos , Células Cultivadas/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Substâncias Perigosas/toxicidade , Hepatócitos/efeitos dos fármacos , Animais , Humanos , Modelos Animais , Inovação Organizacional
7.
Toxicol Mech Methods ; 29(9): 654-664, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31345115

RESUMO

Background: Application of hepatoprotectants, such as drugs or cytokines, can reduce drug-induced hepatotoxicity (DIH). Due to species-specific differences and abnormal cell polarity and drug-metabolizing enzymes (DMEs), in vivo animal models and in vitro 2D plastic dishes are not good DIH models. The aim of this study was to evaluate whether 3D re-cellularized liver is a sensitive, accurate and efficient DIH model for evaluation of hepatoprotectants. Methods: 2D plastic dishes and 3D decellular liver scaffolds were perfused with HepG2 cells or augmenter of liver regeneration (ALR)-HepG2 cells. These two cell lines were exposed to 4 µM troglitazone (TRO) or 20 µM diclofenac sodium (DIC) on day 8. DME-related genes were analyzed by quantitative reverse transcription polymerase chain reaction; morphological images were revealed by immunohistochemistry, scanning electron microscopy, transmission electron microscopy, and hematoxylin and eosin staining. Results: DME activity and cell polarity were retained and lower doses of TRO and DIC led to DIH in 3D re-cellularized liver. This DIH model reflected the protective effects and mechanism of ALR, which is one of the hepatoprotectants. ALR reduced mitochondrial damage, decreased transaminase level, and alleviated inflammation in TRO-DIH and DIC-DIH. Our re-cellularized liver lobe also showed the effect of ALR in suppressing expression of DMEs. Conclusions: Drug-induced 3D re-cellularized tissue engineering is a sensitive, accurate, and efficient DIH model for evaluation of hepatoprotectants.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fígado/efeitos dos fármacos , Modelos Biológicos , Proteínas/genética , Engenharia Tecidual/métodos , Animais , Sobrevivência Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Diclofenaco/toxicidade , Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Fígado/ultraestrutura , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Troglitazona/toxicidade
8.
Opt Lett ; 41(8): 1704-7, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082324

RESUMO

Spatial self-phase modulation (SSPM) experiments on two-dimensional (2D) black phosphorus (BP) nanoflake suspensions are performed with focused femtosecond pulsed lasers at 350-1160 nm. In the broadband region, the slope of the SSPM ring number versus laser intensity varies from 0.99 to 0.34, which is larger than 0.25 in MoS2. We deduce the portion of the fluid globe (ξ) to be 0.0067, which is a constant independent of laser intensity, when the laser intensity is above 10 W/cm2. The nonlinear refractive index of BP is measured to be ∼10(-5) cm2 W(-1), and the third-order nonlinear susceptibility is χ(3)∼10(-8) esu at multiple wavelengths.

9.
Angew Chem Int Ed Engl ; 55(16): 5003-7, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-26968443

RESUMO

A titanium sulfonate ligand is synthesized for surface coordination of black phosphorus (BP). In contrast to serious degradation observed from the bare BP, the BP after surface coordination exhibits excellent stability during dispersion in water and exposure to air for a long period of time, thereby significantly extending the lifetime and spurring broader application of BP.

10.
Cell Biosci ; 14(1): 80, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879547

RESUMO

BACKGROUND: About 1/3 of primary biliary cholangitis (PBC) patients suffered from poor response worldwide. And these patients present intestinal disturbances. We aimed to identify signatures of microbiota and metabolites in PBC patients with poor response, comparing to patients with response. METHODS: This study enrolled 25 subjects (14 PBC patients with response and 11 PBC patients with poor response). Metatranscriptomics and metabolomics analysis were carried out on their fecal. RESULTS: PBC patients with poor response had significant differences in the composition of bacteria, characterized by decreased Gemmiger etc. and increased Ruminococcus etc. The differential microbiota functions characterized by decreased abundance of elongation factor Tu and elongation factor G base on the KO database, as well as decreased abundance of Replicase large subunit etc. based on the SWISS-PROT database. PBC with poor response also had significant differences in 17 kinds of bacterial metabolites, characterized by decreased level of metabolites vital in bile acids metabolism pathway (L-Cysteine etc.) and the all-trans-Retinoic acid, a kind of immune related metabolite. The altered microbiota was associated with the differential expressed metabolites and clinical liver function indicators. 1 bacterial genera, 2 bacterial species and 9 metabolites simultaneously discriminated PBC with poor response from PBC with response with high accuracy. CONCLUSION: PBC patients with poor response exhibit unique changes in microbiota and metabolite. Gut microbiota and metabolite-based algorithms could be used as additional tools for differential prediction of PBC with poor prognosis.

11.
Front Immunol ; 13: 984697, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203614

RESUMO

Background: The human leukocyte antigen (HLA) susceptibility gene is the main genetic risk factor for primary biliary cholangitis (PBC). The prognosis of patients with PBC is linked to gut microbiota dysbiosis. However, whether the HLA alleles are associated with the gut microbiota distribution and disease severity remains unknown. Methods: A cohort of 964 Chinese patients with PBC was enrolled at Beijing YouAn Hospital, Beijing, China. High-resolution genotyping of the HLA class I and class II loci from 151 of these patients was performed using sequence-based PCR. Stool samples were collected from 43 of the 151 fully HLA-typed patients to analyze their microbiota compositions via 16S RNA gene sequencing. Results: Of the 964 patients, the male:female ratio was 114:850, and 342 of these patients (35.5%) had already developed liver cirrhosis (LC) before enrollment. Patients with PBC showed a significantly higher frequency of HLA DRB1*08:03 than did the controls (21.2% vs. 9.0%, P=0.0001). HLA-DRB1*03:01, DRB1*07:01, DRB1*14:05, and DRB1*14:54 frequencies were also increased but did not reach significance after Bonferroni's correction. Conversely, the DQB1*03:01 frequency was significantly lower in patients with PBC than in the controls (24.5% vs. 39.2%, P=0.0010). The patients' gut microbiota were analyzed from four perspectives. The microbial community abundances were significantly lower in FHRAC-positive patients (patients with a combination of five HLA DRB1 high-risk alleles) than in FHRAC-negative patients (P<0.05). Of the top 10 microbial genera, Lachnospiraceae_incertae_sedis was higher in the FHRAC-positive patients than in the FHRAC-negative patients (P<0.05). linear discriminant analysis (LDA) effect-size (LEfSe) analysis showed different microbes at different levels in the FHRAC-negative patients but not in the FHRAC-positive patients. DQB1*03:01-positive patients contained mostly Lactobacillaceae at the family level. A comparison of the FHRAC-positive patients with and without liver cirrhosis showed that the abundances of Veillonella were significantly higher in patients with cirrhosis and FHRAC than in those without cirrhosis and are FHRAC-negative. Conclusion: The HLA class II genes may influence the gut microbiota compositions in patients with PBC. Differential gut microbiota were expressed at different taxonomic levels. Some bacterial abundances may be increased in FHRAC-positive patients with PBC and cirrhosis.


Assuntos
Microbioma Gastrointestinal , Cirrose Hepática Biliar , Feminino , Microbioma Gastrointestinal/genética , Genes MHC da Classe II , Antígenos HLA/genética , Cadeias HLA-DRB1/genética , Humanos , Cirrose Hepática Biliar/genética , Masculino , RNA
12.
Front Med (Lausanne) ; 8: 805029, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34993216

RESUMO

Background: Hepatitis B virus (HBV) infection has been reported to affect the bacterial characteristics in the host. We aimed to elucidate the compositional and functional characteristics of the microbiota in southern Chinese patients with coexistent HBV infection, non-alcoholic fatty liver disease (NAFLD), and type-2 diabetes mellitus (T2DM). Methods: Healthy controls (HCs) and patients with coexistent NAFLD and T2DM were enrolled. Patients were divided into two groups: N1 (without HBV infection) and N2 (with HBV infection). Stool samples were collected for 16s RNA gene sequencing and untargeted metabolomics analysis. Results: Bacterial diversity was decreased in the N2 group. There was a significantly lower abundance of bacteria of Faecalibacterium, Gemmiger, and Clostridium_XIVA genera, but a higher abundance of Megamonas and Phascolarctobacterium genera in the N2 group. Compared with the N1 group, the abundance of Gemmiger species was even lower, and alterations in the abundance of Phascolarctobacterium and Clostridium_XIVA genera only occurred in the N2 group. There were significantly different fecal metabolic features, which were enriched in glucose and lipid metabolic pathways (e.g., fatty acid and glycerophospholipid metabolism) between the N2 and HC groups. Metabolites in glycerophospholipid metabolism, such as Sn-3-o-(geranylgeranyl)glycerol1-phosphate, were even higher in the N2 group than in the N1 group. The decreased Faecalibacterium and Gemmiger contributed to the increased level of Sn-3-o-(geranylgeranyl) glycerol1-phosphate, palmitoylcarnitine, and serum triglycerides. Clostridium_XIVA species were positively correlated to 15(s)-hpete. Megamonas species were positively correlated with the serum level of glucose indirectly. Conclusions: The distinct gut-microbiome profile associated with HBV infection has a role in lipid metabolism and glucose metabolism in patients with coexistent NAFLD and T2DM. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT03525769.

13.
Dis Markers ; 2019: 9121207, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737133

RESUMO

BACKGROUND: The prevalence of primary biliary cholangitis (PBC), which is an autoimmune liver disease, has increased over time. PBC often leads to severe consequences, such as liver failure and death. Stratification tools using biochemical liver tests are needed to assess and predict the progression of this disease at the time of PBC diagnosis. METHODS: We searched PubMed, Cochrane Library, Web of Science, and Embase for studies focused on the relationship between positive rates of Gp210 antibodies and poor prognosis of PBC. The primary end point was the number of PBC patients with poor outcome in the Gp210 antibody (+) and Gp210 antibody (-) groups. The secondary end point was the basic serum level of alanine aminotransferase (ALT), alkaline phosphatase (ALP), total bilirubin (TBIL), and IgM in the two groups. The age and number of female patients were also measured. RESULTS: A total of 5 studies, comprising 737 patients, were included in this analysis. A positive rate of Gp210 antibodies was positively correlated with poor outcomes and with many types of progression in PBC, especially liver failure. Mortality was also higher in the Gp210 antibody (+) group. Furthermore, the serum levels of ALP and IgM were associated with the positive rate of Gp210 antibodies, while the serum levels of ALT and TBIL were not. The age and number of female patients were also not associated with the positive rate of Gp210 antibodies. CONCLUSION: PBC-specific Gp120 antibodies are optimal predictors of PBC prognosis at the time of diagnosis. Some other liver function indicators, such as ALP and IgM, can be used as predictors to complement Gp210 antibodies to establish a stratification tool to predict the prognosis of PBC at the time of diagnosis.


Assuntos
Anticorpos/sangue , Cirrose Hepática Biliar/imunologia , Complexo de Proteínas Formadoras de Poros Nucleares/imunologia , Idoso , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Bilirrubina/sangue , Feminino , Humanos , Imunoglobulina M/sangue , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/mortalidade , Masculino , Pessoa de Meia-Idade , Complexo de Proteínas Formadoras de Poros Nucleares/sangue , Prognóstico
14.
Ther Clin Risk Manag ; 15: 659-668, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190846

RESUMO

Aim: Malnutrition is one of the most common complications in patients with liver cirrhosis. Abnormal energy substrate metabolism may contribute to aggravation of malnutrition. Late evening snack (LESs) supplementation has been recommended as an intervention to reduce starvation time and improve nutritional status. Published studies have analyzed the effect of LESs on the branched-chain amino acid (BCAA)/tyrosine ratio (BTR) and oxidation rate of fat and carbohydrate in patients with liver cirrhosis. Methods: We searched PubMed, Cochrane Library, Web of Science and Embase for relevant research from January 2000 to October 2018. The primary outcome for this analysis was changes in BTR and fat and carbohydrate oxidation in patients with liver cirrhosis. Results: A total of 9 articles, containing 211 patients, were included in this analysis. The results supported that supplementation with BCAA-enriched LESs improved BTR, and long-term supplementation with BCAAs (>1 month) may be more beneficial than short-term supplementation (<1 month) in patients with liver cirrhosis. In addition, supplementation with BCAAs may increase the oxidation rate of carbohydrates and decrease the oxidation rate of fat. Furthermore, compared with liquid-enriched LESs, BCAA was a better choice for increasing the oxidation of carbohydrates and decreasing the rate of fat oxidation. Conclusion: BCAA-enriched LES supplementation is an appropriate nutritional intervention to improve abnormal energy substrate metabolism, which may improve malnutrition in patients with liver cirrhosis. Further research is needed on the long-term benefit and improved survival in patients with liver cirrhosis.

15.
Nanoscale ; 10(44): 20671-20680, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30397700

RESUMO

Dense layers of overlapping three-dimensional (3D) gold nanodendrites characterized by high specific surfaces as well as by abundance of sharp edges and vertices creating high densities of SERS hotspots are promising substrates for SERS-based sensing and catalysis. We have evaluated to what extent structural features of 3D gold nanodendrite layers can be optimized by the initiation of 3D gold nanodendrite growth at gold particles rationally positioned on silicon wafers. For this purpose, galvanic displacement reactions yielding 3D gold nanodendrites were guided by hexagonal arrays of parent gold particles with a lattice constant of 1.5 µm obtained by solid-state dewetting of gold on topographically patterned silicon wafers. Initiation of the growth of dendritic features at the edges of the gold particles resulted in the formation of 3D gold nanodendrites while limitation of dendritic growth to the substrate plane was prevented. The regular arrangement of the parent gold particles supported the formation of dense layers of overlapping 3D gold nanodendrites that were sufficiently homogeneous within the resolution limits of Raman microscopy. Consequently, SERS mapping experiments revealed a reasonable degree of uniformity. The proposed preparation algorithm comprises only bottom-up process steps that can be carried out without the use of costly instrumentation.

16.
ACS Appl Mater Interfaces ; 10(8): 7451-7458, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29384643

RESUMO

Insect-inspired capillary submicron stamping and subsequent surface-limited metal-assisted chemical etching (MACE) with ammonium bifluoride as a HF source are employed for the high-throughput production of ordered topographically patterned silicon (tpSi). Insect feet often possess hairy contact elements through which adhesive secretion is deployed. Thus, arrays of adhesive secretion drops remain as footprints on contact surfaces. Stamps for insect-inspired capillary submicron stamping having surfaces topographically patterned with contact elements mimic the functional principles of such insect feet. They contain spongy continuous nanopore networks penetrating the entire stamps. Any ink (organic or aqueous) may be supplied from the backside of the nanoporous stamps to the contact elements. We generated ordered arrays of submicron AgNO3 dots extending square millimeters on Si by manual stamping with cycle times of a few seconds under ambient conditions; at higher load, ordered holey AgNO3 films were obtained. Surface-limited MACE correspondingly yielded either macroporous tpSi or Si pillar arrays. Inkjet printing of polymer solutions onto the tpSi yielded patterns of polymer blots conformally covering the tpSi. Such blot patterns could potentially represent a starting point for the development of persistent and scratch-resistant identity labels or quick response codes on silicon surfaces.


Assuntos
Silício/química , Polímeros , Impressão , Silício/uso terapêutico
17.
ChemSusChem ; 11(20): 3661-3671, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30095243

RESUMO

A novel oxygen evolution reaction (OER) catalyst (3 D S235-P steel) based on a steel S235 substrate was successfully prepared by facile one-step surface modification. The standard carbon-manganese steel was phosphorized superficially, which led to the formation of a unique 3 D interconnected nanoporous surface with a high specific area that facilitated the electrocatalytically initiated oxygen evolution reaction. The prepared 3 D S235-P steel exhibited enhanced electrocatalytic OER activities in the alkaline regime, as confirmed by a low overpotential (326 mV at a 10 mA cm-2 ) and a small Tafel slope of 68.7 mV dec-1 . Moreover, the catalyst was found to be stable under long-term usage conditions, functioning as an oxygen-evolving electrode at pH 13, as evidenced by the sufficient charge-to-oxygen conversion rate (faradaic efficiency: 82.11 and 88.34 % at 10 and 5 mA cm-2 , respectively). In addition, it turned out that the chosen surface modification delivered steel S235 as an OER electrocatalyst that was stable under neutral pH conditions. Our investigation revealed that the high catalytic activities likely stemmed from the generated Fe/(Mn) hydroxide/oxohydroxides generated during the OER process. Phosphorization treatment therefore not only is an efficient way to optimize the electrocatalytic performance of standard carbon-manganese steel but also enables for the development of low-costing and abundant steels in the field of energy conversion.

18.
J Texture Stud ; 49(1): 2-10, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29052849

RESUMO

Dysphagia is a highly prevalent eating and swallowing disorder among elderly people, impacting negatively on the health and well-being of those afflicted. With increasing populations of elderly people, food industries are under growing pressure to produce appropriately texture-modified food for safe consumption by these vulnerable populations. Recently published International Dysphagia Diet Standardisation Initiative (IDDSI) framework provides a new global guideline on texture modification and standardization for dysphagia patients. This work was designed to test the feasibility of IDDSI framework for clinical applications by assessing the correlation between swallowing capability of dysphagia patients and the IDDSI texture levels. Altogether 26 elderly subjects were recruited and assessed for their dysphagia grades using the Water Drinking Test. Subjects were provided with fluid samples constituted at different consistencies from a commercial product and swallowing performance (time of swallowing, number of swallows, and number of coughs) was monitored and recorded. Correlations among swallowing capability parameters were observed. Most importantly, results from this work clearly demonstrated that the severity of dysphagia by water-based swallow tests correlates positively with the IDDSI fluid thickness aimed at reducing dysphagia symptoms in those patients, confirming the reliability and feasibility of IDDSI framework for clinical applications. PRACTICAL APPLICATIONS: Swallowing disorder or dysphagia occurs commonly among many elderly people and imposes negative impacts on their health and well-being. Medical professionals can diagnose eating and swallowing capability in a qualitative manner, but have difficulty in making diet recommendation because of the lack of texture guidance. This work confirmed the feasibility of IDDSI framework for clinical and bedside applications. The correlation between the capability grades of swallowing and IDDSI texture levels established in this work provides a useful measure for such applications.


Assuntos
Transtornos de Deglutição/dietoterapia , Deglutição , Dieta/normas , Alimentos , Idoso , Idoso de 80 Anos ou mais , Bebidas , Transtornos de Deglutição/reabilitação , Ingestão de Alimentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Política Nutricional , Tamanho da Partícula , Reprodutibilidade dos Testes , Viscosidade , Água
19.
Oncotarget ; 8(8): 12637-12648, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28061452

RESUMO

BACKGROUND: Augmenter of liver regeneration (ALR) exerts strong hepatoprotective properties in various animal models of liver injury, but its protective mechanisms have not yet been explored. Autophagy is a recently recognized rudimentary cellular response to inflammation and injury. The aim of this study was to test the hypothesis that ALR may protect against acute liver injury through the autophagic pathway. METHODS: The level and role of ALR in liver injury were studied in a mouse model of acute liver injury induced by carbon tetrachloride (CCl4). The effect of ALR on autophagy was analyzed in vitro and in vivo. After autophagy was inhibited by 3-methyladenine (3-MA), apoptosis and proliferation were detected in the mouse model with acute liver injury. The ALR and autophagic levels were measured in patients with liver cirrhosis (LC) and acute liver failure (ALF), respectively. RESULTS: During the progression of acute liver injury, the ALR levels increased slightly in early stage and significantly decreased in late stage in mice. Treatment with an ALR plasmid via tail vein injection protected mice against acute liver injury. The protective effect of ALR relied on the induction of autophagy, which was supported by the following evidence: (1) ALR overexpression directly induced autophagy flux in vitro and in vivo; and (2) ALR treatment suppressed apoptosis and promoted proliferation in mice exposed to CCl4, but the inhibition of autophagy reversed these effects. More importantly, the ALR levels decreased in patients with LC and ALF compared with normal controls. CONCLUSION: We demonstrated that ALR ameliorated liver injury via an autophagic mechanism, which indicates a potential therapeutic application for liver injury.


Assuntos
Autofagia/fisiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Hepatopatias/patologia , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Animais , Western Blotting , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Humanos , Cirrose Hepática/metabolismo , Hepatopatias/metabolismo , Falência Hepática Aguda/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Reação em Cadeia da Polimerase em Tempo Real
20.
Nanoscale ; 9(45): 17829-17838, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29115339

RESUMO

The use of proton exchange membrane (PEM) electrolyzers is the method of choice for the conversion of solar energy when frequently occurring changes of the current load are an issue. However, this technique requires electrolytes with low pH. All oxygen evolving electrodes working durably and actively in acids contain IrOx. Due to their scarcity and high acquisition costs, noble elements like Pt, Ru and Ir need to be replaced by earth abundant elements. We have evaluated a cobalt containing steel for use as an oxygen-forming electrode in H2SO4. We found that the dissolving of ingredients out of the steel electrode at oxidative potential in sulfuric acid, which is a well-known, serious issue, can be substantially reduced when the steel is electro-oxidized in LiOH prior to electrocatalysis. Under optimized synthesis conditions a cobalt-containing tool steel was rendered into a durable oxygen evolution reaction (OER) electrocatalyst (weight loss: 39 µg mm-2 after 50 000 s of chronopotentiometry at pH 1) that exhibits overpotentials down to 574 mV at 10 mA cm-2 current density at pH 1. Focused ion beam SEM (FIB-SEM) was successfully used to create a structure-stability relationship.

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