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1.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36769186

RESUMO

H2 permeation in peroxide-crosslinked EPDM blended with carbon black (CB) and silica fillers was studied at pressures ranging from 1.2 MPa to 90 MPa via the volumetric analysis technique. H2 uptake in the CB-filled EPDM revealed dual-sorption behaviors via Henry's law and the Langmuir model, which were attributed to H2 absorption by the polymer chains and H2 adsorption at the filler interfaces, respectively. Additionally, single-sorption mechanisms were observed for neat EPDM and silica-blended EPDM according to Henry's law, indicating H2 absorption by the polymer chain. The linear decreases in the diffusivity with filler content for the silica-blended EPDMs were attributed to increases in the diffusion paths caused by the filler. Exponential decreases in the diffusivity with increasing filler content and in the permeation with the physical/mechanical properties for CB-filled EPDMs were caused by decreases in the fractional free volume due to increased densities for the EPDM composites. Moreover, good filler-dependent correlations between permeability and density, hardness, and tensile strength were demonstrated for EPDMs used as sealing materials for O-rings. From the resulting equation, we predicted the permeation value without further measurements. Thus, we can select EPDM candidates satisfying the permeation guidelines used in hydrogen infrastructure for the future hydrogen economy.


Assuntos
Polímeros , Fuligem , Polímeros/química , Dióxido de Silício , Hidrogênio , Etilenos
2.
Proc Natl Acad Sci U S A ; 115(29): E6741-E6750, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-29954863

RESUMO

Each of the 30 human amyloid diseases is associated with the aggregation of a particular precursor protein into amyloid fibrils. In transthyretin amyloidosis (ATTR), mutant or wild-type forms of the serum carrier protein transthyretin (TTR), synthesized and secreted by the liver, convert to amyloid fibrils deposited in the heart and other organs. The current standard of care for hereditary ATTR is liver transplantation, which replaces the mutant TTR gene with the wild-type gene. However, the procedure is often followed by cardiac deposition of wild-type TTR secreted by the new liver. Here we find that amyloid fibrils extracted from autopsied and explanted hearts of ATTR patients robustly seed wild-type TTR into amyloid fibrils in vitro. Cardiac-derived ATTR seeds can accelerate fibril formation of wild-type and monomeric TTR at acidic pH and under physiological conditions, respectively. We show that this seeding is inhibited by peptides designed to complement structures of TTR fibrils. These inhibitors cap fibril growth, suggesting an approach for halting progression of ATTR.


Assuntos
Amiloide/química , Miocárdio/química , Pré-Albumina/química , Amiloide/metabolismo , Neuropatias Amiloides Familiares/metabolismo , Neuropatias Amiloides Familiares/patologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Pré-Albumina/metabolismo
3.
J Biol Chem ; 294(15): 6130-6141, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30733338

RESUMO

The tetrameric protein transthyretin is a transporter of retinol and thyroxine in blood, cerebrospinal fluid, and the eye, and is secreted by the liver, choroid plexus, and retinal epithelium, respectively. Systemic amyloid deposition of aggregated transthyretin causes hereditary and sporadic amyloidoses. A common treatment of patients with hereditary transthyretin amyloidosis is liver transplantation. However, this procedure, which replaces the patient's variant transthyretin with the WT protein, can fail to stop subsequent cardiac deposition, ultimately requiring heart transplantation. We recently showed that preformed amyloid fibrils present in the heart at the time of surgery can template or seed further amyloid aggregation of native transthyretin. Here we assess possible interventions to halt this seeding, using biochemical and EM assays. We found that chemical or mutational stabilization of the transthyretin tetramer does not hinder amyloid seeding. In contrast, binding of the peptide inhibitor TabFH2 to ex vivo fibrils efficiently inhibits amyloid seeding by impeding self-association of the amyloid-driving strands F and H in a tissue-independent manner. Our findings point to inhibition of amyloid seeding by peptide inhibitors as a potential therapeutic approach.


Assuntos
Neuropatias Amiloides Familiares , Amiloide , Peptídeos/química , Pré-Albumina , Agregados Proteicos , Idoso , Idoso de 80 Anos ou mais , Amiloide/antagonistas & inibidores , Amiloide/química , Amiloide/genética , Amiloide/metabolismo , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Albumina/antagonistas & inibidores , Pré-Albumina/química , Pré-Albumina/genética , Pré-Albumina/metabolismo
4.
Int J Geriatr Psychiatry ; 35(7): 794-801, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32250480

RESUMO

OBJECTIVES: To test whether loneliness is associated with the risk of cognitive impairment up to 11 years later in a European sample of middle-aged and older adults. The study examines whether this association is independent of measures of social isolation, depression, and other risk factors for cognitive impairment and dementia. METHODS: Participants (N = 14 114) from the Survey of Health, Ageing and Retirement in Europe (SHARE) answered a single item on loneliness at baseline and were assessed for cognitive impairment every 2-to-3 years for 11 years. Participants who scored at least 1.5 standard deviations below the age-graded mean on both a memory recall task and verbal fluency task were classified as impaired. A three-item measure of loneliness was available for a sample of respondents followed up to 4 years. RESULTS: Feeling lonely was associated with increased risk of incident cognitive impairment (HR = 1.31, 95%CI = 1.19-1.44), after accounting for age, sex, education, and SHARE country strata. The association was robust but reduced in magnitude when controlling for clinical and behavioral risk factors, health-related activity limitations, social isolation, social disengagement, and depressive symptoms. The association was not moderated by socio-demographic factors and was also apparent when using the three-item loneliness scale instead of the single-item measure. CONCLUSIONS: These findings expand the extant literature on loneliness and the risk of cognitive impairment in older adulthood. Loneliness is one modifiable factor that can be intervened prior to the development of severe impairment or dementia.


Assuntos
Disfunção Cognitiva , Solidão , Adulto , Idoso , Envelhecimento , Disfunção Cognitiva/epidemiologia , Europa (Continente)/epidemiologia , Humanos , Pessoa de Meia-Idade , Aposentadoria
5.
Liver Int ; 38(1): 68-75, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28581248

RESUMO

BACKGROUND & AIMS: We tested whether non-invasive tests for liver disease severity can stratify hepatocellular carcinoma (HCC) risk in chronic hepatitis B virus (HBV)-infected patients showing low-level viremia (LLV, HBV DNA <2000 IU/mL). METHODS: A retrospective cohort of 1006 chronic hepatitis B patients showing persistently LLV, defined by at least two consecutive assessments in the year before enrolment, was assessed for HCC development. Two non-invasive serum biomarkers, the aspartate aminotransferase to platelet ratio index (APRI) and the Fibrosis-4 (FIB-4), were tested. Cirrhosis was defined with ultrasonography. RESULTS: During a median 5.1 years of follow-up, HCC developed in 36 patients. HCC incidence rate at 5 years was significantly higher for cirrhotic patients (19/139, 13.7%), but was not null for non-cirrhotic patients (17/867, 2.0%, P<.001). APRI at a cut-off of 0.5 was more specific but less sensitive for HCC development, and FIB-4 at a cut-off of 1.45 was more sensitive but less specific. When both APRI and FIB-4 were used to group patients, the 5-year cumulative HCC incidence rate was 13.9%, 1.4% and 1.2% for both high, any high, and both low APRI and FIB-4 score among all patients (n=1006, P<.001), respectively, and was 11.4%, 1.5% and 0.4% in the same respective order among non-cirrhotic patients (n=867, P<.001). CONCLUSIONS: The combined use of two non-invasive serum biomarkers (APRI and FIB-4) could stratify HCC risk for chronic HBV-infected patients with LLV.


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/patogenicidade , Hepatite B Crônica/diagnóstico , Cirrose Hepática/diagnóstico , Testes de Função Hepática , Neoplasias Hepáticas/virologia , Viremia/diagnóstico , Adulto , Fatores Etários , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , DNA Viral/sangue , DNA Viral/genética , Progressão da Doença , Feminino , Hepacivirus/genética , Hepatite B Crônica/sangue , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/virologia , Humanos , Incidência , Cirrose Hepática/sangue , Cirrose Hepática/epidemiologia , Cirrose Hepática/virologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Seul/epidemiologia , Índice de Gravidade de Doença , Fatores de Tempo , Ultrassonografia , Carga Viral , Viremia/virologia
6.
Physiol Plant ; 163(4): 450-458, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29315590

RESUMO

Plants must constantly adjust their growth and defense responses to deal with the wide variety of stresses they encounter in their environment. Among phytohormones, brassinosteroids (BRs) are an important group of plant steroid hormones involved in numerous aspects of the plant lifecycle including growth, development and responses to various stresses including insect attacks. Here, we show that BRs regulate glucosinolate (GS) biosynthesis and function in insect herbivory. Preference tests and larval feeding experiments using the generalist herbivore, diamondback moth (Plutella xylostella), revealed that the larvae prefer to feed on Arabidopsis thaliana brassinosteroid insensitive 1 (bri1-5) plants over wild-type Ws-2 or BRI1-Flag (bri1-5 background) transgenic plants, which results in an increase in larval weight. Analysis of GS contents showed that 3-(methylsulfinyl) propyl GS (C3) levels were higher in bri1-5 than in Ws2 and BRI1-Flag transgenic plants, whereas sinigrin (2-propenylglucosinolate), glucoerucin (4-methylthiobutylglucosinolate) and glucobrassicin (indol-3-ylmethylglucosinolate) levels were lower in this mutant. We investigated the effect of brassinolide (BL) on GS biosynthesis in Arabidopsis and radish (Raphanus sativus L.) by monitoring the expression levels of GS biosynthetic genes, including MAM1, MAM3, BCAT4 and AOP2, which increased in a BL-dependent manner. These results suggest that BRs regulate GS profiles in higher plants, which function in defense responses against insects.


Assuntos
Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Glucosinolatos/biossíntese , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Regulação da Expressão Gênica de Plantas , Glucosinolatos/genética , Glucosinolatos/metabolismo , Indóis/metabolismo , Mutação , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Raphanus/genética , Raphanus/metabolismo , Transaminases/genética , Transaminases/metabolismo
7.
Sci Rep ; 14(1): 1967, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263427

RESUMO

A high-performance H2 gas sensor system based on capacitive electrodes and a volumetric analysis technique were developed. Coaxial capacitive electrodes were fabricated by placing a thin copper rod in the center and by adhering a transparent conductive film on the exterior surface of a graduated cylinder. Thus, H2 from a polymer specimen lowered the water level in the cylinder between the two electrodes, producing measurable changes in capacitance that allowed for the measurement of the H2 concentration emitted from the specimen enriched by H2 under high-pressure conditions. The sensing system detected diffused/permeated hydrogen gas from a specimen and hydrogen gas leaks caused by imperfect sealing. The hydrogen gas sensor responded almost instantly at 1 s and measured hydrogen concentrations ranging from 0.15 to 1500 ppm with controllable sensitivity and a measurable range. In addition, performance tests with polymer specimens used in hydrogen infrastructure verified that the sensor system was reliable; additionally, it had a broad measurement range to four decimal places. The sensor system developed in this study could be applied to detect and characterize pure gases (He, N2, O2 and Ar) by real time measurement.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36644439

RESUMO

Bojungikki-tang (BJIT) is a traditional herbal medicine used in Korea, Japan, and China to treat gastrointestinal disorders. In this study, we aimed to investigate whether BJIT has protective effects against radiation-induced intestinal injury and to predict the underlying therapeutic mechanisms and related pathways via network pharmacological analyses. BJIT was injected intraperitoneally (50 mg/kg body weight) to C3H/HeN mice at 36 and 12 h before exposure to partial abdominal irradiation (5 Gy and 13 Gy) to evaluate the apoptotic changes and the histological changes and variations in inflammatory cytokine mRNA levels in the jejunum, respectively. Through in silico network analysis, we predicted the mechanisms underlying BJIT-mediated regulation of radiation-induced intestinal injury. BJIT reduced the level of apoptosis in the jejunal crypts 12 h post 5-Gy irradiation. Histological assessment revealed intestinal morphological changes in irradiated mice 3.5 days post 13-Gy irradiation. Furthermore, BJIT decreased inflammatory cytokine levels following radiation exposure. Apoptosis, TNF, p53, VEGF, toll-like receptor, PPAR, PI3K-Akt, and MAPK signaling pathways, as well as inflammatory bowel disease (IBD), were found to be linked to the radioprotective effects of BJIT against intestinal injury. According to our results, BJIT exerted its potential protective effects by attenuating histopathological changes in jejunal crypts and suppressing inflammatory mediator levels. Therefore, BJIT is a potential therapeutic agent that can treat radiation-induced intestinal injury and its associated symptoms.

9.
Front Immunol ; 14: 1225047, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37822938

RESUMO

Introduction: Trauma patients are susceptible to coagulopathy and dysfunctional immune responses. Mesenchymal stromal cells (MSCs) are at the forefront of the cellular therapy revolution with profound immunomodulatory, regenerative, and therapeutic potential. Routine assays to assess immunomodulation activity examine MSC effects on proliferation of peripheral blood mononuclear cells (PBMCs) and take 3-7 days. Assays that could be done in a shorter period of time would be beneficial to allow more rapid comparison of different MSC donors. The studies presented here focused on assays for MSC suppression of mitogen-stimulated PBMC activation in time frames of 24 h or less. Methods: Three potential assays were examined-assays of apoptosis focusing on caspase activation, assays of phosphatidyl serine externalization (PS+) on PBMCs, and measurement of tumor necrosis factor alpha (TNFα) levels using rapid ELISA methods. All assays used the same initial experimental conditions: cryopreserved PBMCs from 8 to 10 pooled donors, co-culture with and without MSCs in 96-well plates, and PBMC stimulation with mitogen for 2-72 h. Results: Suppression of caspase activity in activated PBMCs by incubation with MSCs was not robust and was only significant at times after 24 h. Monitoring PS+ of live CD3+ or live CD4+/CD3+ mitogen-activated PBMCs was dose dependent, reproducible, robust, and evident at the earliest time point taken, 2 h, although no increase in the percentage of PS+ cells was seen with time. The ability of MSC in co-culture to suppress PBMC PS+ externalization compared favorably to two concomitant assays for MSC co-culture suppression of PBMC proliferation, at 72 h by ATP assay, or at 96 h by fluorescently labeled protein signal dilution. TNFα release by mitogen-activated PBMCs was dose dependent, reproducible, robust, and evident at the earliest time point taken, with accumulating signal over time. However, suppression levels with MSC co-culture was reliably seen only after 24 h. Discussion: Takeaways from these studies are as follows: (1) while early measures of PBMC activation is evident at 2-6 h, immunosuppression was only reliably detected at 24 h; (2) PS externalization at 24 h is a surrogate assay for MSC immunomodulation; and (3) rapid ELISA assay detection of TNFα release by PBMCs is a robust and sensitive assay for MSC immunomodulation at 24 h.


Assuntos
Células-Tronco Mesenquimais , Linfócitos T , Humanos , Leucócitos Mononucleares , Fator de Necrose Tumoral alfa/farmacologia , Mitógenos/farmacologia , Terapia de Imunossupressão/métodos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Caspases
10.
Bio Protoc ; 13(18): e4814, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37753473

RESUMO

Device-induced thrombosis remains a major complication of extracorporeal life support (ECLS). To more thoroughly understand how blood components interact with the artificial surfaces of ECLS circuit components, assessment of clot deposition on these surfaces following clinical use is urgently needed. Scanning electron microscopy (SEM), which produces high-resolution images at nanoscale level, allows visualization and characterization of thrombotic deposits on ECLS circuitry. However, methodologies to increase the quantifiability of SEM analysis of ECLS circuit components have yet to be applied clinically. To address these issues, we developed a protocol to quantify clot deposition on ECLS membrane oxygenator gas transfer fiber sheets through digital and SEM imaging techniques. In this study, ECLS membrane oxygenator fiber sheets were obtained, fixed, and imaged after use. Following a standardized process, the percentage of clot deposition on both digital images and SEM images was quantified using ImageJ through blind reviews. The interrater reliability of quantitative analysis among reviewers was evaluated. Although this protocol focused on the analysis of ECLS membrane oxygenators, it is also adaptable to other components of the ECLS circuits such as catheters and tubing. Key features • Quantitative analysis of clot deposition using digital and scanning electron microscopy (SEM) techniques • High-resolution images at nanoscale level • Extracorporeal life support (ECLS) devices • Membrane oxygenators • Blood-contacting surfaces Graphical overview.

11.
Eur J Immunol ; 41(10): 2937-46, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21792879

RESUMO

The active metabolite of vitamin D(3), 1α,25(OH)(2)D(3) , displays anticancer effects by regulating cell cycle and apoptosis in many cancer cells. However, it has not been determined whether 1α,25(OH)(2)D(3) increases the susceptibility of cancer cells to NK cells. Here, we investigated the anticancer effect of 1α,25(OH)(2)D(3) in human melanoma cell lines by investigating enhancement of NK susceptibility and elucidating the mediator of NK cytotoxicity. 1α,25(OH)(2)D(3)-resistant melanoma cells (G-361 and SK-MEL-5) treated with 1α,25(OH)(2)D(3) showed higher susceptibility to NK cells with up-regulation of Fas expression. Furthermore, G-361 cells treated with 1α,25(OH)(2)D(3) showed significantly increased caspase activity. In addition to Fas up-regulation, expression of heat shock protein 60 (Hsp60) was elevated by 1α,25(OH)(2) D(3) . Increased expression of Hsp60 by 1α,25(OH)(2)D(3) was related to not only up-regulation of Fas expression but also to NK susceptibility of G-361 cells. Taken together, our data suggest that 1α,25(OH)(2)D(3) acts as an anticancer agent by increasing expression of Fas on the surface of melanoma cells through Hsp60 induction and strengthens caspase sensitivity to Fas-mediated apoptotic pathway by NK cells. 1α,25(OH)(2)D(3) treatment may therefore have a preventive role in melanoma occurrence or potentiate the anticancer effects of NK-cell immune therapy.


Assuntos
Calcitriol/farmacologia , Chaperonina 60/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Melanoma/tratamento farmacológico , Receptor fas/metabolismo , Apoptose/imunologia , Western Blotting , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Proteína Ligante Fas/metabolismo , Citometria de Fluxo , Humanos , Melanoma/imunologia , Melanoma/metabolismo , Interferência de RNA , RNA Interferente Pequeno
12.
Medicine (Baltimore) ; 100(50): e28261, 2021 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-34918698

RESUMO

RATIONALE: Granulosa cell tumors (GCTs) account for less than 2% of all ovarian malignancies and are the second most common ovarian sex cord stromal tumors after fibroma/thecomas.GCTs occur most frequently in postmenopausal women with a peak age of 50 to 55, are usually diagnosed in their early stages, and have a good prognosis. GCTs usually present with features of hyperestrogenism, with an average size is 10 to 15 cm. PATIENT CONCERNS: A 31-year-old nulligravida diagnosed with polycystic ovarian syndrome (PCOS) 10 years prior, had a 20-mm mass in her right ovary found on ultrasonography 2 years ago. She had been taking dienogest 2 mg for 2 years for a misdiagnosed endometrioma, but over a 2-year course, the mass increased to 50 mm. DIAGNOSES: An ultrasound scan revealed a 47 × 37-mm round solid mass in the right ovary with a spongiform appearance and little vascularity. The pathologic findings showed an adult-type granulosa cell tumor with necrosis and hemorrhage. The tissue stained positive for inhibin-α, Wilms' tumor-1, CD56, and negative for cytokeratin 7. INTERVENTIONS: We finally performed right salpingo-oophorectomy, endometrial biopsy, peritoneal biopsy, and partial omentectomy. The pathological findings were adult-type granulosa cell tumor. The International Federation of Gynecology and Obstetrics staging was IA. The patient did not require additional treatment. OUTCOMES: Surprisingly, her normal menstruation returned 2 weeks after the operation, and she had a normal pregnancy and parturition. The patient had been followed-up regularly for 3 years following the surgery. The patient has not experienced any complications and has remained disease-free. LESSONS: GCTs should be considered in the differential diagnosis if a female patient with PCOS and amenorrhea shows a unilateral small solid mass. They are extremely rare malignant ovarian tumors that must be differentiated from other benign ovarian tumors, especially endometriomas and dermoid cysts. It was difficult for us to suspect a granulosa cell tumor because the patient already had PCOS symptoms such as mild hirsutism and amenorrhea. This case highlights the importance of physicians being aware of and suspicious for GCTs in similar cases, along with knowing their characteristics in considering possible differential diagnoses.


Assuntos
Tumor de Células da Granulosa/patologia , Neoplasias Ovarianas/patologia , Síndrome do Ovário Policístico/complicações , Adulto , Amenorreia , Biópsia , Feminino , Tumor de Células da Granulosa/cirurgia , Humanos , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/cirurgia , Síndrome do Ovário Policístico/patologia , Síndrome do Ovário Policístico/cirurgia , Salpingo-Ooforectomia , Ultrassonografia
13.
Redox Biol ; 47: 102162, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34628272

RESUMO

RATIONALE: Cell-based therapeutics have been extensively used for cardiac repair yet underperform due to inability of the donated cells to survive in near anoxia after cardiac injury. Cellular metabolism is linked to maintenance of cardiac stem cell (CSC) renewal, proliferation and survival. Ex vivo expansion alters (CSC) metabolism increasing reliance on oxygen dependent respiration. Whether promoting 'metabolic flexibility' in CSCs augments their ability to survive in near anoxia and repair the heart after injury remains untested. OBJECTIVE: Determine the effect of LIN28a induced metabolic flexibility on cardiac tissue derived stem like cell (CTSC) survival and repair after cardiac injury. METHODS AND RESULTS: LIN28a expression coincides during heart development but is lost in adult CTSCs. Reintroduction of LIN28a in adult CTSC (CTSC-LIN) increased proliferation, survival, expression of pluripotency genes and reduced senescence compared to control (CTSC-GFP). Metabolomic analysis show glycolytic intermediates upregulated in CTSC-LIN together with increased lactate production, pyruvate kinase activity, glucose uptake, ECAR and expression of glycolytic enzymes compared to CTSC-GFP. Additionally, CTSC-LIN showed significantly reduced ROS generation and increase antioxidant markers. In response to H2O2 induced oxidative stress, CTSC-LIN showed increased survival and expression of glycolytic genes. LIN28a salutary effects on CTSCs were linked to PDK1/let-7 signaling pathway with loss of PDK1 or alteration of let-7 abrogating LIN28a effects. Following transplantation in the heart after myocardial infarction (MI), CTSC-LIN showed 6% survival rate at day 7 after injection compared to control cells together with increased proliferation and significant increase in cardiac structure and function 8 weeks after MI. Finally, CSTC-LIN showed enhanced ability to secrete paracrine factors under hypoxic conditions and ability to promote cardiomyocyte proliferation following ischemic cardiac injury. CONCLUSIONS: LIN28a modification promotes metabolic flexibility in CTSCs enhancing proliferation and survival post transplantation including ability to repair the heart after myocardial injury.


Assuntos
Peróxido de Hidrogênio , Infarto do Miocárdio , Proteínas de Ligação a RNA/metabolismo , Animais , Sobrevivência Celular , Coração , Humanos , Camundongos , Oxirredução
14.
J Biol Chem ; 284(38): 25697-703, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19620707

RESUMO

Cysteine proteases of the papain superfamily are implicated in a number of cellular processes and are important virulence factors in the pathogenesis of parasitic disease. These enzymes have therefore emerged as promising targets for antiparasitic drugs. We report the crystal structures of three major parasite cysteine proteases, cruzain, falcipain-3, and the first reported structure of rhodesain, in complex with a class of potent, small molecule, cysteine protease inhibitors, the vinyl sulfones. These data, in conjunction with comparative inhibition kinetics, provide insight into the molecular mechanisms that drive cysteine protease inhibition by vinyl sulfones, the binding specificity of these important proteases and the potential of vinyl sulfones as antiparasitic drugs.


Assuntos
Antiparasitários/química , Cisteína Endopeptidases/química , Plasmodium falciparum/enzimologia , Inibidores de Proteases/química , Proteínas de Protozoários/química , Sulfonas/química , Trypanosoma brucei brucei/enzimologia , Trypanosoma cruzi/enzimologia , Animais , Antiparasitários/uso terapêutico , Doença de Chagas/tratamento farmacológico , Doença de Chagas/enzimologia , Cristalografia por Raios X , Desenho de Fármacos , Cinética , Malária Falciparum/tratamento farmacológico , Malária Falciparum/enzimologia , Inibidores de Proteases/uso terapêutico , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas de Protozoários/antagonistas & inibidores , Sulfonas/uso terapêutico , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/enzimologia
15.
PeerJ ; 8: e9504, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32864202

RESUMO

Cytokine signaling in the epidermis has an important role in maintaining barrier function and is perturbed in pathological conditions. Environmental exposures, such as to metal compounds, are of interest for their potential contribution to skin disease. Present work explores the possibility that vanadate is a more effective protein tyrosine phosphatase inhibitor in human keratinocytes than previously observed in fibroblasts. It focuses on the state of phosphorylation of signal transducer and activator of transcription 1 (STAT1) on tyrosine 701 upon treatment of cultured human keratinocytes with the cytokine oncostatin M, a cutaneous inflammatory mediator that is highly effective in suppressing several differentiation markers and in preserving proliferative potential of keratinocytes. Exposure to sodium vanadate in the medium greatly prolonged the phosphorylation of STAT1, but only at high concentration (>30 µM). Inhibitors of protein tyrosine phosphatases known to dephosphorylate STAT1 (SHP2, TCPTP, PTP1B) were ineffective in mimicking the action of vanadate. The irreversible protein tyrosine phosphatase inhibitor phenyl vinyl sulfonate alone induced STAT1 phosphorylation and appeared to induce its limited cleavage. It also inhibited cross-linked envelope formation, a characteristic step of keratinocyte terminal differentiation, likely due to its reaction with the active site cysteine of keratinocyte transglutaminase. Thus, the key protein tyrosine phosphatase responsible for STAT1 dephosphorylation remains to be identified, and an off-target effect of a potential inhibitor was revealed.

16.
Ann Behav Med ; 36(2): 129-40, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18797978

RESUMO

BACKGROUND: Lung cancer morbidity and mortality may increase the risk for distress in couples facing this malignancy. PURPOSE: We examined the prevalence of psychological and relationship distress in lung cancer patients and their spouses, predictors of psychological distress for both, and whether relationship satisfaction moderated the relation between patient and spouse distress. METHODS: Participants (169 patients and 167 spouses) completed questionnaires provided during clinic appointments at baseline (within one month of treatment initiation) and through the mail 3 and 6 months later. Analyses were from the baseline data. RESULTS: In total, 34.6% of patients and 36.4% of spouses reported psychological distress. Patient and spouse distress were correlated, depending on the symptom examined. Only 10.9% of patients and 14.1% of spouses reported distressed spousal relationships. Distress predictors for patients included less positive social interaction support, more behavioral disengagement and self-distraction coping, and the spouse reporting less use of humor for coping. Predictors for spouses included more behavioral disengagement and substance use coping, more blaming the patient for causing the cancer, and the patient using more behavioral disengagement coping. Relationship satisfaction moderated the association between each partner's distress. CONCLUSIONS: Psychosocial counseling for lung cancer patients should include spouses and target decreasing individual distress and enhancing relationship satisfaction.


Assuntos
Efeitos Psicossociais da Doença , Relações Interpessoais , Neoplasias Pulmonares/psicologia , Cônjuges/psicologia , Estresse Psicológico/complicações , Adaptação Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Aconselhamento , Feminino , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/terapia , Masculino , Casamento/psicologia , Pessoa de Meia-Idade , Modelos Psicológicos , Escalas de Graduação Psiquiátrica , Apoio Social , Estresse Psicológico/terapia
17.
Int J Dermatol ; 57(1): 55-61, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29090468

RESUMO

BACKGROUND: Becker's nevus (BN) presents as a hairy patch or plaque with or without proliferation of the dermal smooth muscles. BN has been described as acquired as found in a similar entity, congenital smooth muscle hamartoma (CSMH). This study was aimed at evaluating the clinicopathological aspects of BN in Korean cases in differential diagnosis with CSMH. METHODS: We performed a retrospective study of 103 patients histopathologically diagnosed as having BN or CSMH. The cases included 40 cases diagnosed with BN or CSMH before the age of 10 years who had clinical monitoring and a second skin biopsy after puberty to determine the disease course. RESULTS: Among cases of children to adolescents (<18 years), we observed a slight male predominance. Among children aged <14 years, sex ratio converged at 1:1. Early-onset BN showed a female predominance and hyperpigmented skin lesions. All BN cases showed hyperpigmentation, and face and neck involvement tended to make severe cosmetic concerns. In contrast, hypertrichosis was more frequent in CSMH. Either skin-colored lesion or pseudo-Darier's sign was not seen in early-onset BN. BN showed less dermal smooth muscle than CSMH. CONCLUSIONS: Androgens themselves do not seem to be related to the development of BN but play only an aggravating role especially in male patients. Considering high occurrence in exposed areas, BN may distress patients severely. As early laser treatment may be helpful in some patients with BN, early-onset BN in comparison to CSMH should be diagnosed appropriately.


Assuntos
Hamartoma/diagnóstico , Doenças Musculares/diagnóstico , Nevo/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adolescente , Idade de Início , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Hamartoma/complicações , Hamartoma/congênito , Hamartoma/patologia , Humanos , Hiperpigmentação/etiologia , Hipertricose/etiologia , Lactente , Recém-Nascido , Masculino , Músculo Liso , Doenças Musculares/complicações , Doenças Musculares/congênito , Doenças Musculares/patologia , Nevo/complicações , Nevo/patologia , República da Coreia , Estudos Retrospectivos , Fatores Sexuais , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/patologia
18.
J Invest Dermatol ; 135(8): 1977-1985, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25806854

RESUMO

Capsaicin has many biological effects, such as antioxidant, anticancer, and antiangiogenic effects, but it is rarely used because of its high pungency. Capsiate, a nonpungent capsaicin analog, also has multiple biological effects, similar to those of capsaicin, but does not cause irritation. However, the effect of capsiate on allergic responses and immune cells has not been well studied. In this study, we investigated the effect of capsiate on atopic dermatitis, mouse CD4+ T cells, and mast cell activation. Capsiate inhibited DNFB-induced atopic dermatitis in NC/Nga mice. Topical treatment with capsiate suppressed serum IgE levels and cytokine and chemokine expression in the skin of DNFB-treated NC/Nga mice. In addition, it suppressed the activation of CD4+ T cells and mast cells, which are implicated in allergic diseases. Capsiate inhibited the differentiation of naïve CD4+ T cells into T helper type 1 (Th1), Th2, and Th17 cells. Treatment with capsiate inhibited the expression of pro-inflammatory cytokines and degranulation from activated bone marrow-derived mast cells through the inhibition of extracellular signal-regulated kinase signal pathways. Consistent with these results, treatment with capsiate inhibited passive cutaneous anaphylaxis. Taken together, our results suggest that capsiate might be a good candidate molecule for the treatment of allergic diseases such as atopic dermatitis.


Assuntos
Linfócitos T CD4-Positivos/patologia , Capsaicina/análogos & derivados , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Mastócitos/patologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dermatite Atópica/induzido quimicamente , Dinitrofluorbenzeno/efeitos adversos , Modelos Animais de Doenças , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Mutantes , Anafilaxia Cutânea Passiva/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/patologia
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