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1.
Adv Mater ; : e2314031, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38509794

RESUMO

Electrocatalytic water splitting is crucial to generate clean hydrogen fuel, but implementation at an industrial scale remains limited due to dependence on expensive platinum (Pt)-based electrocatalysts. Here, an all-dry process to transform electrochemically inert bulk WS2 into a multidomain electrochemical catalyst that enables scalable and cost-effective implementation of the hydrogen evolution reaction (HER) in water electrolysis is reported. Direct dry transfer of WS2 flakes to a gold thin film deposited on a silicon substrate provides a general platform to produce the working electrodes for HER with tunable charge transfer resistance. By treating the mechanically exfoliated WS2 with sequential Ar-O2 plasma, mixed domains of WS2, WO3, and tungsten oxysulfide form on the surfaces of the flakes, which gives rise to a superior HER with much greater long-term stability and steady-state activity compared to Pt. Using density functional theory, ultraefficient atomic sites formed on the constituent nanodomains are identified, and the quantification of atomic-scale reactivities and resulting HER activities fully support the experimental observations.

2.
Life Sci ; 310: 121076, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36243116

RESUMO

Cadmium (Cd) is one of the most toxic heavy metals used in various industries, including metal plating, batteries and plastics and environmental pollutant. Cd in the environment is a detrimental factor that cannot be biodegraded and accumulates in human organs. The skin is the first target organ after Cd topical exposure. Curcumin is a natural dietary polyphenolic compound with many beneficial effects, including antioxidant, anti-inflammatory and anticancer activities. However, the effect of curcumin against Cd-induced toxicity in human keratinocytes has not been reported. In this study, we investigated the effects of curcumin against Cd-induced apoptosis in keratinocytes and the underlying molecular mechanisms. Cd resulted in apoptosis as shown by Annexin V/7-AAD double staining. Cd promoted the cleavage of poly (ADP ribose) polymerase-1 (PARP-1) and caspase 3 and suppressed Bcl-2. In addition, Cd induced the release of cytochrome c and Smac from the mitochondria into the cytosol, which is an intrinsic apoptosis-specific process. Curcumin inhibited the early and late apoptosis caused by Cd. The changes in apoptotic markers induced by Cd were significantly reversed by curcumin. Next, we evaluated the effect of curcumin on metallothionein (MT), a cysteine-rich protein that plays a key role in metal detoxification. Curcumin increased the level of MT2A mRNA and the expression of MT2. Interestingly, the antiapoptotic effects of curcumin were reversed under the knockdown of MT2A, suggesting that MT2A is a critical target of curcumin. These findings indicate the potential of curcumin as a novel compound for protection against Cd-mediated skin damage by MT2A modulation.


Assuntos
Cádmio , Curcumina , Humanos , Cádmio/toxicidade , Cádmio/metabolismo , Curcumina/farmacologia , Curcumina/metabolismo , Mitocôndrias/metabolismo , Apoptose , Metalotioneína/genética , Metalotioneína/metabolismo
3.
Clin Exp Dermatol ; 47(12): 2303-2305, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36006169

RESUMO

We report a clinical experience of treating concomitant atopic dermatitis and hidradenitis suppurativa (HS) with dupilumab. This report is particularly noticeable in terms of disease severity and treatment duration compared to previous reported cases, suggesting long-term dupilumab therapy can contribute to disease control even in patients with severe HS.


Assuntos
Dermatite Atópica , Hidradenite Supurativa , Humanos , Dermatite Atópica/complicações , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/induzido quimicamente , Hidradenite Supurativa/complicações , Hidradenite Supurativa/tratamento farmacológico , Hidradenite Supurativa/induzido quimicamente , Anticorpos Monoclonais Humanizados/uso terapêutico , Índice de Gravidade de Doença , Resultado do Tratamento
4.
J Med Food ; 25(6): 652-659, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35708629

RESUMO

Cholestatic liver disease, or cholestasis, is a condition characterized by liver inflammation and fibrosis following a bile duct obstruction and an intrahepatic accumulation of bile acids. Inhibiting inflammation is a promising therapeutic strategy for cholestatic liver diseases. Acer tegmentosum Maxim extract (ATE) is best known for its anti-inflammatory and antioxidative properties. In this study, we investigated the effects of ATE on liver injury and fibrosis in mice with bile duct ligation (BDL)-induced cholestasis through analysis of gene expression, cytokines, and histological examination. Oral administration of ATE (20 or 50 mg/kg) for 14 days significantly attenuated hepatocellular necrosis compared to vehicle-treated BDL mice, which was accompanied by the reduced level of serum bile acids and bilirubin. We determined that ATE treatment reduced liver inflammation, oxidative stress, and fibrosis. These beneficial effects of ATE were concurrent with the decreased expression of genes involved in the NF-κB pathway, suggesting that the anti-inflammatory effect of ATE could be a possible mechanism against cholestasis-associated liver injury. Our findings substantiate ATE's role as an alternative therapeutic agent for cholestasis-induced liver injury and fibrosis.


Assuntos
Acer , Colestase , Hepatite , Animais , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Ácidos e Sais Biliares/uso terapêutico , Ductos Biliares/metabolismo , Ductos Biliares/cirurgia , Colestase/tratamento farmacológico , Colestase/metabolismo , Colestase/patologia , Fibrose , Hepatite/complicações , Hepatite/tratamento farmacológico , Hepatite/patologia , Inflamação/tratamento farmacológico , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Camundongos , Extratos Vegetais/farmacologia
5.
J Breast Cancer ; 25(2): 106-116, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35506579

RESUMO

PURPOSE: The aim of this study was to evaluate the radiological response rate patterns during neoadjuvant chemotherapy (NAC) in patients with breast cancer. METHODS: Patients who underwent NAC with two specific chemotherapy regimens (doxorubicin with cyclophosphamide or doxorubicin with docetaxel) and who underwent a response evaluation every two cycles were included in the study. The initial response ratio was defined as the ratio of the largest tumor diameter at diagnosis to that after two cycles of NAC. The latter response ratio was defined as the ratio between the tumor size after two cycles and that after four cycles of NAC. The radiological response rate pattern was divided into three groups: the fast-to-slow response group (F-S group, initial response ratio > latter response ratio + 20%), slow-to-fast response group (S-F group, latter response ratio > initial response ratio + 20%), and constant response group (less than 20% difference between the initial and latter response ratios). RESULTS: In total, 177 patients were included in the analysis. Forty-two (23.9%) patients were categorized into the F-S group, 26 (14.8%) into the S-F group, and 108 (61.2%) into the constant group. Clinicopathologic factors did not differ according to radiologic response rate patterns. The median follow-up period was 50 months (range, 3-112) months. In the univariate analysis, the F-S group had a significantly worse recurrence-free survival than the S-F and constant groups (hazard ratio [HR], 3.63; 95% confidence interval [CI], 1.05-12.46; p = 0.041). The F-S group also presented with significantly worse survival than the S-F group in the multivariate analysis (HR, 3.45; 95% CI, 1.00-11.89; p = 0.049). CONCLUSION: The F-S group had a poorer survival rate than the S-F group. Radiological response rate patterns may be useful for accurate prognostic assessments, especially when considering post-neoadjuvant therapy.

6.
Biotechnol Bioeng ; 119(8): 2250-2260, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35445397

RESUMO

Pikromycin is an important precursor of drugs, for example, erythromycin. Hence, systems metabolic engineering for the enhanced pikromycin production can contribute to the development of pikromycin-related drugs. In this study, metabolic genes in Streptomyces venezuelae were systematically engineered for enhanced pikromycin production. For this, a genome-scale metabolic model of S. venezuelae was reconstructed and simulated, which led to the selection of 11 metabolic gene targets. These metabolic genes, including four overexpression targets and seven knockdown targets, were individually engineered first. Next, two overexpression targets and two knockdown targets were selected based on the 11 strains' production performances to engineer two to four of these genes together for the potential synergistic effects on the pikromycin production. As a result, the NM1 strain with AQF52_RS24510 (methenyltetrahydrofolate cyclohydrolase/methylenetetrahydrofolate dehydrogenase) overexpression and AQF52_RS30320 (sulfite reductase) knockdown showed the best production performance among all the 22 strains constructed in this study. Fed-batch fermentation of the NM1 strain produced 295.25 mg/L of pikromycin, by far the best production titer using the native producer S. venezuelae, to the best of our knowledge. The systems metabolic engineering strategy demonstrated herein can also be applied to the overproduction of other secondary metabolites using S. venezuelae.


Assuntos
Engenharia Metabólica , Streptomyces , Macrolídeos/metabolismo , Streptomyces/genética , Streptomyces/metabolismo
7.
Nature ; 603(7902): 631-636, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35322249

RESUMO

Metastable phases-kinetically favoured structures-are ubiquitous in nature1,2. Rather than forming thermodynamically stable ground-state structures, crystals grown from high-energy precursors often initially adopt metastable structures depending on the initial conditions, such as temperature, pressure or crystal size1,3,4. As the crystals grow further, they typically undergo a series of transformations from metastable phases to lower-energy and ultimately energetically stable phases1,3,4. Metastable phases sometimes exhibit superior physicochemical properties and, hence, the discovery and synthesis of new metastable phases are promising avenues for innovations in materials science1,5. However, the search for metastable materials has mainly been heuristic, performed on the basis of experiences, intuition or even speculative predictions, namely 'rules of thumb'. This limitation necessitates the advent of a new paradigm to discover new metastable phases based on rational design. Such a design rule is embodied in the discovery of a metastable hexagonal close-packed (hcp) palladium hydride (PdHx) synthesized in a liquid cell transmission electron microscope. The metastable hcp structure is stabilized through a unique interplay between the precursor concentrations in the solution: a sufficient supply of hydrogen (H) favours the hcp structure on the subnanometre scale, and an insufficient supply of Pd inhibits further growth and subsequent transition towards the thermodynamically stable face-centred cubic structure. These findings provide thermodynamic insights into metastability engineering strategies that can be deployed to discover new metastable phases.

8.
Small Methods ; 6(5): e2200074, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35212468

RESUMO

Copper-based catalysts have attracted enormous attention due to their high selectivity for C2+ products during the electrochemical reduction of CO2 (CO2 RR). In particular, grain boundaries on the catalysts contribute to the generation of various Cu coordination environments, which have been found essential for C-C coupling. However, smooth-surfaced Cu2 O nanocrystals generally lack the ability for the surface reorganization to form multiple grain boundaries and desired Cu undercoordination sites. Flow chemistry armed with the unparalleled ability to mix reaction mixture can achieve a very high concentration of unstable reaction intermediates, which in turn are used up rapidly to lead to kinetics-driven nanocrystal growth. Herein, the synthesis of a unique hierarchical structure of Cu2 O with numerous steps (h-Cu2 O ONS) via flow chemistry-assisted modulation of nanocrystal growth kinetics is reported. The surface of h-Cu2 O ONS underwent rapid surface reconstruction under CO2 RR conditions to exhibit multiple heterointerfaces between Cu2 O and Cu phases, setting the preferable condition to facilitate C-C bond formation. Notably, the h-Cu2 O ONS obtained the increased C2 H4 Faradaic efficiency from 31.9% to 43.5% during electrocatalysis concurrent with the morphological reorganization, showing the role of the stepped surface. Also, the h-Cu2 O ONS demonstrated a 3.8-fold higher ethylene production rate as compared to the Cu2 O nanocube.

9.
J Cell Mol Med ; 25(22): 10430-10440, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34651412

RESUMO

Hypoxic-ischaemic encephalopathy (HIE) is a type of brain injury affecting approximately 1 million newborn babies per year worldwide, the only treatment for which is therapeutic hypothermia. Thrombin-preconditioned mesenchymal stem cells (MSCs) exert neuroprotective effects by enriching cargo contents and boosting exosome biogenesis, thus showing promise as a new therapeutic strategy for HIE. This study was conducted to evaluate the tissue distribution and potential toxicity of thrombin-preconditioned human Wharton's jelly-derived mesenchymal stem cells (th-hWJMSCs) in animal models before the initiation of clinical trials. We investigated the biodistribution, tumorigenicity and general toxicity of th-hWJMSCs. MSCs were administered the maximum feasible dose (1 × 105 cells/10 µL/head) once, or at lower doses into the cerebral ventricle. To support the clinical use of th-hWJMSCs for treating brain injury, preclinical safety studies were conducted in newborn Sprague-Dawley rats and BALB/c nude mice. In addition, growth parameters were evaluated to assess the impact of th-hWJMSCs on the growth of newborn babies. Our results suggest that th-hWJMSCs are non-toxic and non-tumorigenic in rodent models, survive for up to 7 days in the brain and hold potential for HIE therapy.


Assuntos
Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Trombina/metabolismo , Geleia de Wharton/citologia , Animais , Animais Recém-Nascidos , Biomarcadores , Transformação Celular Neoplásica , Gerenciamento Clínico , Modelos Animais de Doenças , Humanos , Hipóxia-Isquemia Encefálica/etiologia , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Ratos , Trombina/farmacologia
10.
Int J Mol Sci ; 22(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34681581

RESUMO

As the central node between nutrition signaling input and the metabolic pathway, AMP-activated protein kinase (AMPK) is tightly regulated to maintain energy homeostasis. Subcellular compartmentalization of AMPK is one of the critical regulations that enables AMPK to access proper targets and generate appropriate responses to specific perturbations and different levels of stress. One of the characterized localization mechanisms is RanGTPase-driven CRM1 that recognizes the nuclear export sequence (NES) on the α subunit to translocate AMPK into the cytoplasm. Nuclear localization putatively employs RanGTPase-driven importin that might recognize the nuclear localization signal (NLS) present on the AMPKα2 kinase domain. Nucleo-cytoplasmic shuttling of AMPK is influenced by multiple factors, such as starvation, exercise, heat shock, oxidant, cell density, and circadian rhythm. Tissue-specific localization, which distributes AMPK trimers with different combinations, has also been shown to be vital in maintaining tissue-specific metabolism. Tissue-specific and subcellular distribution of AMPK might be attributed to differences in the expression of the subunit, the stabilization by protein regulators, tissue activity, and the localization of AMPK activators. Considering the importance of AMPK localization in coordinating signaling and metabolism, further research is due to fully elucidate the largely unknown complex mechanism underlying this regulation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Metabolismo Energético , Proteínas Quinases Ativadas por AMP/química , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Ritmo Circadiano , Citoplasma/metabolismo , Resposta ao Choque Térmico , Humanos , Carioferinas/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína Exportina 1
11.
PLoS One ; 16(5): e0250986, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33970925

RESUMO

BACKGROUND: Yes-associated protein 1 (YAP1) is a key effector molecule regulated by the Hippo pathway and described as a poor prognostic factor in breast cancer. Tumor protein 53 (TP53) mutation is well known as a biomarker related to poor survival outcomes. So far clinical characteristics and survival outcome according to YAP1 and TP53 mutation have been poorly identified in breast cancer. PATIENTS AND METHODS: Retrospectively, 533 breast tumor tissues were collected at the Seoul St Mary's hospital and Gangnam Severance Hospital from 1992 to 2017. Immunohistochemistry with YAP1 and p53 specific antibodies were performed, and the clinical data were analyzed. RESULTS: Mutant p53 pattern was associated with aggressive tumor features and advanced anatomical stage. Inferior overall survival (OS) and recurrence free survival (RFS) were related with mutant p53 pattern cases with low nuclear YAP1 expression (P = 0.0009 and P = 0.0011, respectively). Multivariate analysis showed that mutant p53 pattern was an independent prognostic marker for OS [hazard ratios (HR): 2.938, 95% confidence intervals (CIs): 1.028-8.395, P = 0.044] and RFS (HR: 1.842, 95% CIs: 1.026-3.304). However, in cases with high nuclear YAP1 expression, there were no significantly difference in OS and RFS according to p53 staining pattern. CONCLUSION: We found that mutant p53 pattern is a poor prognostic biomarker in breast tumor with low nuclear YAP1 expression. Our findings suggest that interaction between nuclear YAP1 and p53 expression pattern impact survival outcomes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Mutação , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Núcleo Celular/metabolismo , Feminino , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Proteínas de Sinalização YAP
12.
J Breast Cancer ; 24(2): 175-182, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33818021

RESUMO

PURPOSE: Li-Fraumeni syndrome (LFS) is a rare autosomal cancer syndrome caused by a germline mutation in the TP53 gene. Breast cancer in LFS patients is of various subtypes; however, limited data are available on the clinicopathological features of these subtypes and their appropriate treatments. This study aimed to review the clinical features and treatments for breast cancer in South Korean patients with germline TP53 mutations. METHODS: Data on the clinicopathological features and treatment of all breast cancer patients with LFS were collected retrospectively from the available database of 4 tertiary hospitals in the Republic of Korea. RESULTS: Twenty-one breast cancer cases in 12 unrelated women with confirmed germline TP53 mutations were included in the study. The median age at diagnosis was 33.5 years. The histopathological diagnosis included invasive ductal carcinoma (n = 16), ductal carcinoma in situ (n = 3), and malignant phyllodes tumor (n = 2). While 42% and 31% of the cases were positive for estrogen and progesterone receptors, respectively, 52.6% were human epidermal growth factor receptor 2 (HER2) positive, and 21% were triple-negative. The treatments included mastectomy (52%) and breast-conserving surgery (38%). Five patients underwent radiotherapy (RT). The median follow-up period was 87.5 (8-222) months. There were 3 ipsilateral and 4 contralateral breast recurrences during the follow-up, and 8 patients developed new primary cancers. In the post-RT subgroup, there were 2 ipsilateral and 2 contralateral breast recurrences in 1 patient, and 4 patients had a new primary cancer. CONCLUSION: As reported in other countries, breast cancer in LFS patients in South Korea had an early onset and were predominantly but not exclusively positive for HER2. A multidisciplinary approach with adherence to the treatment guidelines, considering mastectomy, and avoiding RT is encouraged to prevent RT-associated sequelae in LFS patients.

13.
J Ethnopharmacol ; 275: 114138, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33895248

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Platycodon grandiflorus (Jacq.) A.DC. is a well-known traditional herbal medicine administered for bronchitis and inflammatory diseases. Especially, anti-inflammatory effect of fermented P. grandiflorus (Jacq.) A.DC. extract (FPGE) was higher than that of P. grandiflorus (Jacq.) A.DC. extract. However, toxicological information for FPGE is lacking. AIM OF THE STUDY: In this study, we establish a toxicological profile for FPGE by testing genotoxicity, acute and 13-week subchronic toxicity. MATERIALS AND METHODS: FPGE was evaluated with bacterial reverse mutation, chromosome aberration, and micronucleus test. For the acute- and 13-week subchronic toxicity tests, FPGE was administered orally at doses of 0, 750, 1500, and 3000 mg/kg in SD rats. RESULTS: The results of the genotoxic assays indicated that FPGE induced neither mutagenicity nor clastogenicity. The acute toxicity test showed that FPGE did not affect animal mortality, clinical signs, body weight changes, or microscopic findings at ≤ 3000 mg/kg. The approximate lethal dose (ALD) of FPGE in SD rats was >3000 mg/kg. For the 13-week subchronic toxicity assay, no FPGE dose induced any significant change in mortality, clinical signs, body or organ weight, food consumption, ophthalmology, urinalysis, hematology, serum chemistry, gross findings and histopathologic examination in either SD rat sex. The rat no observed adverse effects level (NOAEL) for FPGE was set to 3000 mg/kg. CONCLUSIONS: The present study empirically demonstrated that FPGE has a safe preclinical profile and indicated that it could be safely integrated into health products for atopic dermatitis treatment.


Assuntos
Dano ao DNA/efeitos dos fármacos , Extratos Vegetais/toxicidade , Platycodon/química , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Aberrações Cromossômicas/efeitos dos fármacos , Cricetulus , Ingestão de Alimentos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Fermentação , Rim/efeitos dos fármacos , Rim/patologia , Pulmão/efeitos dos fármacos , Masculino , Testes para Micronúcleos , Testes de Mutagenicidade , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos Sprague-Dawley , Salmonella typhimurium/efeitos dos fármacos , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
14.
Ecotoxicol Environ Saf ; 211: 111947, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33503546

RESUMO

The chicken (Gallus gallus), which has three aryl hydrocarbon receptor (AHR) isoforms (ckAHR1, ckAHR2, and ckAHR1ß) and two AHR nuclear translocator (ARNT) isoforms (ckARNT1 and ckARNT2), is highly sensitive to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and can serve as an avian model to gain an understanding of the mechanism underlying dioxin toxicity. To elucidate the mechanism of TCDD-induced immunotoxicity in avian species, we treated chicken embryos in ovo with graded concentrations of TCDD (1.5, 2.5, 3.0, 3.3, 3.5, and 4.0 µM). Initially, we measured mRNA expression levels of ckAHR and ckARNT isoforms and analyzed the T cell populations and transcriptome in the thymuses of TCDD-treated chicken embryos. Quantitative polymerase chain reaction analysis revealed that mRNA expressions of ckAHR1 and ckARNT2 were dominant in the thymus. Severe weight loss and thymus atrophy were observed in the TCDD-treated embryos. Immunophenotyping analyses demonstrated significant increases in CD4+CD8-CD25+ and CD4+CD8+CD25+ regulatory T cells (Tregs) populations following TCDD exposure, suggesting that TCDD suppresses T cell-mediated immune responses in chicken embryos. In addition, thymic transcriptome analyses intimated that alteration of the signaling pathways related to erb-b2 receptor tyrosine kinase 4 (ERBB4) and wnt family member 5A (WNT5A), and bone morphogenetic protein (BMP) may be associated with the TCDD-induced thymus atrophy. We also observed significantly altered expression levels of genes including interleukine 13 receptor subunit alpha 2 (IL13RA2), transforming growth factor beta 1 (TGFß1), collagen type III alpha 1 chain (COL3A1), and collagen type IX alpha 3 chain (COL9A3), implying immunosuppression, fibrosis development, and collagen deposition. Collectively, these findings suggest that TCDD exposure activates the ckAHR1-ckARNT2 signaling pathway and suppresses immune responses through the prompted differentiation to CD4+CD8-CD25+ and CD4+CD8+CD25+ Tregs and altered expressions of immune-related genes in the thymus of chicken embryos.


Assuntos
Poluentes Ambientais/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Embrião de Galinha , Galinhas/metabolismo , Sistema Imunitário/efeitos dos fármacos , Isoformas de Proteínas/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Linfócitos T , Transcriptoma
15.
Anesth Pain Med (Seoul) ; 15(4): 466-471, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33329850

RESUMO

BACKGROUND: Fontan-associated liver disease (FALD) is a hepatic disorder caused by hemodynamic changes and systemic venous congestion following the Fontan procedure. FALD includes liver cirrhosis and hepatocellular carcinoma (HCC), both of which may require liver transplantation (LT). However, the Fontan circulation, characterized by elevated central venous pressure and reduced cardiac output, is a challenging issue for surgeons and anesthesiologists. CASE: We report a living-donor LT for the treatment of HCC. The patient was a 24-year-old male who underwent the Fontan procedure for pulmonary atresia and right ventricle hypoplasia. We focused on maintaining enough blood volume for cardiac output without causing pulmonary edema, as the patient is not well adapted to changes in volume. Owing to a multidisciplinary approach, the surgery was successfully performed without fatal adverse events. CONCLUSIONS: To our knowledge, this is the first case of isolated LT in a recipient who became an adult after having undergone the Fontan procedure.

16.
Sci Rep ; 10(1): 13699, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792596

RESUMO

Light element identification is necessary in materials research to obtain detailed insight into various material properties. However, reported techniques, such as scanning transmission electron microscopy (STEM)-energy dispersive X-ray spectroscopy (EDS) have inadequate detection limits, which impairs identification. In this study, we achieved light element identification with nanoscale spatial resolution in a multi-component metal alloy through unsupervised machine learning algorithms of singular value decomposition (SVD) and independent component analysis (ICA). Improvement of the signal-to-noise ratio (SNR) in the STEM-EDS spectrum images was achieved by combining SVD and ICA, leading to the identification of a nanoscale N-depleted region that was not observed in as-measured STEM-EDS. Additionally, the formation of the nanoscale N-depleted region was validated using STEM-electron energy loss spectroscopy and multicomponent diffusional transformation simulation. The enhancement of SNR in STEM-EDS spectrum images by machine learning algorithms can provide an efficient, economical chemical analysis method to identify light elements at the nanoscale.

17.
Micromachines (Basel) ; 11(8)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751667

RESUMO

Metal-assisted chemical etching (MACE) is widely used to fabricate micro-/nano-structured Si owing to its simplicity and cost-effectiveness. The technique of magnetically guided MACE, involving MACE with a tri-layer metal catalyst, was developed to improve etching speed as well as to adjust the etching direction using an external magnetic field. However, the controllability of the etching direction diminishes with an increase in the etching dimension, owing to the corrosion of Fe due to the etching solution; this impedes the wider application of this approach for the fabrication of complex micro Si structures. In this study, we modified a tri-layer metal catalyst (Au/Fe/Au), wherein the Fe layer was encapsulated to improve direction controllability; this improved controllability was achieved by protecting Fe against the corrosion caused by the etching solution. We demonstrated curved Si microgroove arrays via magnetically guided MACE with Fe encapsulated in the tri-layer catalyst. Furthermore, the curvature in the curved Si microarrays could be modulated via an external magnetic field, indicating that direction controllability could be maintained even for the magnetically guided MACE of bulk Si. The proposed fabrication method developed for producing curved Si microgroove arrays can be applied to electronic devices and micro-electromechanical systems.

18.
Biochem Pharmacol ; 168: 452-464, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31421133

RESUMO

Evogliptin is a novel, potent and selective dipeptidyl peptidase 4 inhibitor that has received approval for use in the treatment of type 2 diabetes in South Korea. In the management of diabetes, it is important to reduce cardiovascular risk factors, as this can decrease the complication and mortality rate. However, the effect of evogliptin on the atherosclerotic progression has not been evaluated. In this study, we examined the effects of evogliptin on the progression of atherosclerosis and its possible mechanism of action. The anti-atherosclerotic effect of evogliptin was evaluated in ApoE-knockout mice fed high-fat diet analysed by plaque lesion formation, lipid profiles and vascular inflammatory response in the atherosclerotic progression. The in vitro effects of evogliptin were verified in endothelial cells analysed by immunoblotting, siRNA gene knockdown, promoter-luciferase assay, immunoprecipitation and adhesion assay. Evogliptin reduced the high-fat diet-induced atherosclerotic plaque area in the ApoE-/- mouse model. Macrophage infiltration into lesions was suppressed in the evogliptin group. In the endothelial cells, evogliptin inhibited inflammatory responses via suppression of adhesion molecules induced by TNF-α. TNF-α-mediated activation of NF-κB was ameliorated by evogliptin via the interaction of NF-κB with SIRT1 (Sirtuin-1). TNF-α-mediated adhesion between endothelial cells and monocytes was inhibited by evogliptin, but this inhibitory effect was reversed by Sirt1 gene knockdown. This study demonstrates that the protective effect of evogliptin on atherosclerotic progression via inhibition of vascular inflammation. The findings imply that evogliptin has potential for anti-atherosclerosis therapy that targets arterial inflammation.


Assuntos
Aterosclerose/tratamento farmacológico , Inflamação/tratamento farmacológico , NF-kappa B/metabolismo , Piperazinas/farmacologia , Sirtuína 1/metabolismo , Animais , Aterosclerose/induzido quimicamente , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Knockout para ApoE , NF-kappa B/genética , Sirtuína 1/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
19.
Nanoscale ; 11(30): 14266-14275, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31317997

RESUMO

Two-dimensional (2D) MoS2 nanostructures have been extensively investigated in recent years because of their fascinating electrocatalytic properties. Herein, we report 2D hybrid nanostructures consisting of 1T' phase MoS2 and Fe-phthalocyanine (FePc) molecules that exhibit excellent catalytic activity toward both the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). X-ray absorption spectra revealed an increased Fe-N distance (2.04 Å) in the hybrid complex relative to the isolated FePc. Spin-polarized density functional theory calculations predicted that the Fe center moves toward the MoS2 layer and induces a non-planar structure with an increased Fe-N distance of 2.05 Å, which supports the experimental results. The experiments and calculations consistently show a significant charge transfer from FePc to stabilize the hybrid complex. The excellent HER catalytic performance of FePc-MoS2 is characterized by a low Tafel slope of 32 mV dec-1 at a current density of 10 mA cm-2 and an overpotential of 0.123 V. The ORR catalytic activity is superior to that of the commercial Pt/C catalyst in pH 13 electrolyte, with a more positive half-wave potential (0.89 vs. 0.84 V), a smaller Tafel slope (35 vs. 87 mV·dec-1), and a much better durability (9.3% vs. 40% degradation after 20 h). Such remarkable catalytic activity is ascribed to the HER-active 1T' phase MoS2 and the ORR-active nonplanar Fe-N4 site of FePc.

20.
J Am Chem Soc ; 141(11): 4624-4633, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30702874

RESUMO

In this study, we demonstrate that the initial morphology of nanoparticles can be transformed into small fragmented nanoparticles, which were densely contacted to each other, during electrochemical CO2 reduction reaction (CO2RR). Cu-based nanoparticles were directly grown on a carbon support by using cysteamine immobilization agent, and the synthesized nanoparticle catalyst showed increasing activity during initial CO2RR, doubling Faradaic efficiency of C2H4 production from 27% to 57.3%. The increased C2H4 production activity was related to the morphological transformation over reaction time. Twenty nm cubic Cu2O crystalline particles gradually experienced in situ electrochemical fragmentation into 2-4 nm small particles under the negative potential, and the fragmentation was found to be initiated from the surface of the nanocrystal. Compared to Cu@CuO nanoparticle/C or bulk Cu foil, the fragmented Cu-based NP/C catalyst achieved enhanced C2+ production selectivity, accounting 87% of the total CO2RR products, and suppressed H2 production. In-situ X-ray absorption near edge structure studies showed metallic Cu0 state was observed under CO2RR, but the fragmented nanoparticles were more readily reoxidized at open circuit potential inside of the electrolyte, allowing labile Cu states. The unique morphology, small nanoparticles stacked upon on another, is proposed to promote C-C coupling reaction selectivity from CO2RR by suppressing HER.

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