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1.
Sci Rep ; 14(1): 2309, 2024 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-38280903

RESUMO

Epithelial-mesenchymal transition (EMT) is the process by which epithelial cells acquire mesenchymal characteristics. This process induces cell migration and invasion, which are closely related to cancer metastasis and malignancy. EMT consists of various intermediate states that express both epithelial and mesenchymal traits, called partial EMT. Recently, several studies have focused on the roles of voltage-gated potassium (Kv) channels associated with EMT in cancer cell migration and invasion. In this study, we demonstrate the relationship between Kv3.4 and EMT and confirm the effects of cell migration and invasion. With TGF-ß treatment, EMT was induced and Kv3.4 was also increased in A549 cells, human lung carcinoma cells. The knockdown of Kv3.4 blocked the EMT progression reducing cell migration and invasion. However, the Kv3.4 overexpressed cells acquired mesenchymal characteristics and increased cell migration and invasion. The overexpression of Kv3.4 also has a synergistic effect with TGF-ß in promoting cell migration. Therefore, we conclude that Kv3.4 regulates cancer migration and invasion through TGF-ß-induced EMT and these results provide insights into the understanding of cancer metastasis.


Assuntos
Neoplasias Pulmonares , Fator de Crescimento Transformador beta , Humanos , Células A549 , Fator de Crescimento Transformador beta/farmacologia , Linhagem Celular Tumoral , Fator de Crescimento Transformador beta1/farmacologia , Neoplasias Pulmonares/patologia , Transição Epitelial-Mesenquimal , Movimento Celular
2.
Phytomedicine ; 103: 154209, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35689901

RESUMO

BACKGROUND: Leaky gut symptoms and inflammatory bowel disease (IBD) are associated with damaged intestinal mucosa, intestinal permeability dysfunction by epithelial cell cytoskeleton contraction, disrupted intercellular tight junction (TJ) protein expression, and abnormal immune responses and are intractable diseases. PURPOSE: We evaluated the effects of schisandrin C, a dibenzocyclooctadiene lignan from Schisandra chinensis, on intestinal inflammation and permeability dysfunction in gut mimetic systems: cultured intestinal cells, intestinal organoids, and a Caenorhabditis elegans model. METHODS: Schisandrin C was selected from 9 lignan compounds from S. chinensis based on its anti-inflammatory effects in HT-29 human intestinal cells. IL-1ß and Pseudomonas aeruginosa supernatants were used to disrupt intestinal barrier formation in vitro and in C. elegans, respectively. The effects of schisandrin C on transepithelial electrical resistance (TEER) and intestinal permeability were evaluated in intestinal cell monolayers, and its effect on intestinal permeability dysfunction was tested in mouse intestinal organoids and C. elegans by measuring fluorescein isothiocyanate (FITC)-dextran efflux. The effect of schisandrin C on TJ protein expression was investigated by western blotting and fluorescence microscopy. The signaling pathway underlying these effects was also elucidated. RESULTS: Schisandrin C ameliorated intestinal permeability dysfunction in three IBD model systems and enhanced epithelial barrier formation via upregulation of ZO-1 and occludin in intestinal cell monolayers and intestinal organoids. In Caco-2 cells, schisandrin C restored IL-1ß-mediated increases in MLCK and p-MLC expression, in turn blocking cytoskeletal contraction and subsequent intestinal permeabilization. Schisandrin C inhibited NF-ĸB and p38 MAPK signaling, which regulates MLCK expression and structural reorganization of the TJ complex in Caco-2 cells. Schisandrin C significantly improved abnormal FITC-dextran permeabilization in both intestinal organoids and C. elegans. CONCLUSION: Schisandrin C significantly improves abnormal intestinal permeability and regulates the expression of TJ proteins, long MLCK, p-MLC, and inflammation-related proteins, which are closely related to leaky gut symptoms and IBD development. Therefore, schisandrin C is a candidate to treat leaky gut symptoms and IBDs.


Assuntos
Doenças Inflamatórias Intestinais , Lignanas , Animais , Células CACO-2 , Caenorhabditis elegans/metabolismo , Ciclo-Octanos , Humanos , Inflamação/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/metabolismo , Lignanas/farmacologia , Camundongos , Quinase de Cadeia Leve de Miosina/metabolismo , Organoides/metabolismo , Permeabilidade , Compostos Policíclicos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas
3.
Anal Chem ; 94(17): 6463-6472, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35435669

RESUMO

Raman thermometry based on surface-enhanced Raman scattering has been developed using nanopipettes in cancer cell photothermal therapy (PTT). Gold nanorods (AuNRs) are robustly epoxied on glass pipettes with a high surface coverage of ∼95% and less than 10 nm-wide nanogaps for intracellular thermometry and photothermal cancer therapy. The temperature changes could be estimated from the N≡C band shifts of 4-fluorophenyl isocyanide (FPNC)-adsorbed AuNRs on the Raman thermometry nanopipette (RTN) surfaces. An intracellular temperature change of ∼2.7 °C produced by altering the [Ca2+] in A431 cells was detected using the RTN in vitro, as checked from fura-2 acetoxymethyl ester (fura-2 AM) fluorescence images. For in vivo experiments, local temperature rises of ∼19.2 °C were observed in the mouse skin, whereas infrared camera images could not tract due to spatial resolution. In addition, a tumor growth suppression was observed in the PTT processes after an administration of the three AuNR-coated nanopipettes combined with a 671 nm laser irradiation for 5 min in 30 days. These results demonstrate not only the localized temperature sensing ability of FPNC-tagged AuNR nanopipettes in cell biology but also anti-cancer effects in photothermal cancer therapy.


Assuntos
Nanotubos , Neoplasias , Termometria , Animais , Linhagem Celular Tumoral , Fura-2 , Ouro , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neoplasias/terapia , Terapia Fototérmica
4.
Int J Mol Sci ; 24(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36614004

RESUMO

Porphyrin compounds are widely distributed in various natural products and biological systems. In this study, effects of porphyrin-related compounds including zinc protoporphyrin (ZnPP), protoporphyrin IX (PPIX), cyanocobalamin (CBL), hemin, and zinc phthalocyanine (ZnPC) were analyzed on color response of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) tetrazolium-based assay, a commonly-used method for analyzing cell viability. Color responses of MTT formazan formed in cells treated with ZnPP, PPIX, or ZnPC were significantly reduced even at submicromolar concentrations without affecting cell viability, whereas hemin and CBL did not. ZnPP, PPIX, and ZnPC rapidly induced degradation of MTT formazan already-produced by cells when exposed to light, but not under a dark condition. Photosensitizing properties of the three compounds were also verified through extensive generation of reactive oxygen species under light. The porphyrins did not affect the stability of water-soluble formazans including XTT, WST-1, WST-8, and MTS formazans. Several factors including different light sources and antioxidants modulated the degradation process of MTT formazan by the porphyrins. The results suggest that certain porphyrin compounds could cause a severe artifact in the MTT assay through rapid degradation of formazan dye due to their photosensitizing property, which needs to be considered carefully in the related assays.


Assuntos
Colorimetria , Porfirinas , Formazans/metabolismo , Porfirinas/farmacologia , Hemina
5.
J Nat Prod ; 84(7): 2020-2027, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34236881

RESUMO

The tropolone-bearing sesquiterpenes juniperone A (1) and norjuniperone A (2) were isolated from the folk medicinal plant Juniperus chinensis, and their structures were determined by a combination of spectroscopic and crystallographic methods. Photojuniperones A1 (3) and A2 (4), bearing bicyclo[3,2,0]heptadienones derived from tropolone, were photochemically produced and structurally identified by spectroscopic methods. Predicted by the machine learning-based assay, 1 significantly inhibited the action of tyrosinase. The new compounds also inhibited lipid accumulation and enhanced the extracellular glycerol excretion.


Assuntos
Juniperus/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Sesquiterpenos/farmacologia , Tropolona/farmacologia , Animais , Células Hep G2 , Humanos , Melanócitos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Fotoquímica , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , República da Coreia , Sesquiterpenos/isolamento & purificação , Tropolona/isolamento & purificação , Madeira/química
6.
Food Nutr Res ; 642020.
Artigo em Inglês | MEDLINE | ID: mdl-33240033

RESUMO

BACKGROUND: Climacterium is a series of physical and mental symptoms occurring in women and men due to decreased levels of sex hormones. Women lose the ability to become pregnant due to decreased ovarian estrogen production; the initial symptom being hot flushes. In addition, urogenital atrophy, sexual dysfunction, mood changes, and osteoporosis occur. Extracts of Stauntonia hexaphylla (SH) and Vaccinium bracteatum (VB) fruits, with a wide range of biological activities, are widely used in traditional herbal medicine. OBJECTIVE: The purpose of this study was to investigate the mitigation of menopausal symptoms, such as hot flushes and postmenopausal osteoporosis after combinatorial treatment with SH and VB (SHVB) of ovariectomized (OVX) rats. DESIGN: We measured the bone regenerative effect of SHVB on receptor activator of nuclear factor-κB (NF-κB) ligand-induced osteoclast differentiation in vitro and on ovariectomy-induced osteoporosis in vivo. We investigated the effect of SHVB in a rat model of menopausal hot flushes, in which the tail skin temperature increases following ovariectomy-induced rapid decline in estrogen levels. RESULTS: SHVB inhibited osteoclast formation and tartrate-resistant acid phosphatase activity in primary mouse bone marrow-derived cells. In an estrogen deficiency-induced rat model, measurement of serum bone turnover factors showed that treatment with SHVB lowered the increased bone turnover. Additionally, SHVB decreased OVX-induced bone loss of the total femur. SHVB inhibited osteoclast differentiation, prevented bone mass reduction, and improved trabecular bone structure and biochemical markers in OVX-induced osteoporosis. In addition, administration of SHVB significantly ameliorated the changes in skin temperature in OVX rats. CONCLUSION: SHVB improved the symptoms of menopause. These results provide the foundation for developing SHVB as a natural substance to replace hormones in the future.

7.
Anticancer Res ; 40(3): 1387-1394, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32132035

RESUMO

BACKGROUND/AIM: Cancer cells are frequently exposed to microenvironmental stresses, including amino acid deprivation and hypoxia, which are often targeted for cancer therapy. Here, we examined the effect of hypoxia in cysteine-deprived breast cancer cells and the mechanism to counteract the hypoxia effect. MATERIALS AND METHODS: Cell death was determined by annexin V-FITC and propidium iodide staining. Expression of mRNAs and proteins was determined by reverse transcription polymerase chain reaction and western blot analysis, respectively. RESULTS: Cysteine deprivation or sulfasalazine, a potent inhibitor of cysteine/glutamate transporter, induced cell death by activating transcription factor 4 (ATF4) up-regulation. Hypoxia significantly suppressed cell death and ATF4 up-regulation induced by cysteine deprived conditions. In addition, tumor necrosis factor-related apoptosis-inducing ligand reversed the effect of hypoxia on cysteine deprived conditions. CONCLUSION: Prevention of hypoxia may be a means for augmenting the effect of amino acid deprivation as a strategy for cancer therapy.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Neoplasias da Mama/metabolismo , Cisteína/deficiência , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Morte Celular/fisiologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Cisteína/antagonistas & inibidores , Cisteína/metabolismo , Feminino , Humanos , Sulfassalazina/farmacologia , Transfecção , Regulação para Cima
8.
Biotechnol Lett ; 42(4): 519-528, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31970557

RESUMO

OBJECTIVES: To investigate the preventive effect of Lactobacillus casei HY2782 on toxicity induced by particulate matter (PM, inhalable particles less than 10 µm in diameter) in human intestinal CCD-18Co cells and a model animal Caenorhabditis elegans. RESULTS: L. casei HY2782 treatment prevented PM-induced intestinal cell death via cellular reactive oxygen species production and membrane disruption attenuation. PM significantly decreased the total number of eggs laid and the body bending activity of C. elegans, demonstrating PM toxicity. L. casei HY2782 treatment restored the reproductive toxicity and decline in locomotion activity induced by PM in C. elegans. Overall, L. casei HY2782 attenuated PM toxicity in vitro in cultured intestinal cells and in vivo in the model nematode. CONCLUSION: Our study provides a potential clue for developing L. casei HY2782 probiotics that attenuate PM-induced cellular and physiological toxicity; however, further in-depth preclinical trials using mammalian animal models and clinical trials are required.


Assuntos
Caenorhabditis elegans/fisiologia , Intestinos/citologia , Lacticaseibacillus casei/fisiologia , Material Particulado/toxicidade , Animais , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Intestinos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
9.
Oncol Rep ; 41(5): 3119-3126, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864724

RESUMO

Redd1 is a stress response protein that functions as a repressor of mTORC1, a central regulator of protein translation, resulting in the inhibition of cell growth and metabolism. However, paradoxically, high Redd1 expression favors cancer progression and generates resistance to cancer therapy. Herein, we revealed that constitutive overexpression of Redd1 induced HSP27 and HSP70 expression in lung cancer cells. The expression of Redd1, HSP27 and HSP70 was highly increased in lung cancer tissues compared with that in normal lung tissues. Inhibition of HSP27 or HSP70 suppressed AKT phosphorylation, which was induced by constitutive overexpression of Redd1 and enhanced the inhibitory effects on viability of Redd1­overexpressing cells. Inhibition of AKT phosphorylation resulted in a decrease of HSP27 and HSP70 expression in Redd1­overexpressing cells. These data indicated that HSPs and AKT in Redd1­overexpressing cells positively regulated the function and expression of each other and were involved in lung cancer cell survival. Knockdown of HSP27, HSP70 or AKT enhanced ionizing radiation (IR) sensitivity, particularly in lung cancer cells in which Redd1 was stably overexpressed. Collectively, constitutive overexpression of Redd1 led to HSP27 and HSP70 induction and AKT activation, which were involved in lung cancer cell survival and resistance to IR, suggesting that Redd1 may be used as a therapeutic target for lung cancer.


Assuntos
Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias Pulmonares/radioterapia , Tolerância a Radiação , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Proteínas de Choque Térmico , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Chaperonas Moleculares , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Radiação Ionizante , Transdução de Sinais/efeitos da radiação , Fatores de Transcrição/genética
10.
Biochem Biophys Res Commun ; 508(1): 191-197, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471853

RESUMO

CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), a multifunctional E3 ligase protein with many target proteins, is involved in diverse developmental processes throughout the plant's lifecycle, including seed germination, the regulation of circadian rhythms, photomorphogenesis, and the control of flowering time. To function, COP1 must form multimeric complexes with SUPPRESSOR OF PHYA1 (SPA1), i.e., [(COP1)2(SPA1)2] tetramers. We recently reported that the blue-light receptor FKF1 (FLAVIN-BINDING, KELCH REPEAT, F-BOX1) represses COP1 activity by inhibiting its homodimerization, but it is not yet clear whether FKF1 affects the formation of COP1-containing multimeric complexes. To explore this issue, we performed size exclusion chromatography (SEC) of Arabidopsis thaliana proteins and found that the levels and composition of COP1-containing multimeric complexes varied throughout a 24-h period. The levels of 440-669 kDa complexes were dramatically reduced in the late afternoon compared to the morning and at night in wild-type plants. During the daytime, the levels of these complexes were reduced in FKF1-overexpressing plants but not in fkf1-t, a loss-of-function mutant of FKF1, suggesting that FKF1 is closely associated with the destabilization of COP1 multimeric protein complexes in a light-dependent manner. We also analyzed the SEC patterns of COP1 multimeric complexes in transgenic plants overexpressing mutant COP1 variants, including COP1L105A (which forms homodimers) and COP1L170A (which cannot form homodimers), and found that COP1 multimeric complexes were scarce in plants overexpressing COP1L170A. These results indicate that COP1 homodimers serve as basic building blocks that assemble into COP1 multimeric complexes with diverse target proteins. We propose that light-activated FKF1 inhibits COP1 homodimerization, mainly by destabilizing 440-669 kDa COP1 complexes, resulting in the repression of CONSTANS-degrading COP1 activity in the late afternoon in long days, but not in short days, thereby regulating photoperiodic flowering in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/biossíntese , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/efeitos da radiação , Arabidopsis/metabolismo , Arabidopsis/efeitos da radiação , Luz , Ubiquitina-Proteína Ligases/biossíntese , Ubiquitina-Proteína Ligases/efeitos da radiação , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cromatografia em Gel , Mutação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
11.
Korean J Fam Med ; 39(5): 279-283, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29972899

RESUMO

BACKGROUND: Epidemiological studies suggest that serum calcium levels correlate with cardiovascular events. An ankle-brachial index (ABI) between 0.9 and 1.00 is a surrogate estimation of preclinical peripheral arterial disease (PAD). Prior studies have shown that an ABI of 0.9-1.0 is also associated with endothelial dysfunction. Therefore, we sought to investigate the relationship between serum calcium levels and preclinical PAD in apparently healthy Korean individuals. METHODS: We evaluated the association between serum calcium levels and preclinical PAD in 596 participants (334 males, 262 females) in a health examination program. Preclinical PAD was defined by an ABI of 0.9-1.0. Multiple logistic regression analysis was used to determine whether the serum calcium level was an independent determinant of preclinical PAD. RESULTS: The overall prevalence of preclinical PAD was 14.3%. The mean age was 44.0±12.5 years in the non-PAD group and 48.3±11.4 years in the preclinical PAD group (P=0.001). After adjusting for age, gender, systolic blood pressure, fasting plasma glucose, high-density lipoprotein cholesterol, triglycerides, C-reactive protein, g-glutamyltransferase, uric acid, hypertension medication, diabetes medication, and hyperlipidemia medication, the odds ratio (95% confidence intervals) for preclinical PAD was 2.28 (1.02-5.11) with a 1-mg/dL increase in the serum calcium. CONCLUSION: These findings suggest that increased serum calcium is independently and positively associated with preclinical PAD regardless of the presence of classic cardiovascular risk factors.

12.
BMB Rep ; 51(4): 163-164, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29580375

RESUMO

CONSTANS (CO) induces the expression of FLOWERING LOCUS T (FT) in the photoperiodic pathway, and thereby regulates the seasonal timing of flowering. CO expression is induced and CO protein is stabilized by FLAVIN-BINDING KELCH REPEAT F-BOX PROTEIN 1 (FKF1) in the late afternoon, while CO is degraded by CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1) during the night. These regulatory cascades were thought to act independently. In our study, we investigated the relationship between FKF1 and COP1 in the regulation of CO stability in response to ambient light conditions. A genetic analysis revealed that FKF1 acts as a direct upstream negative regulator of COP1, in which cop1 mutation is epistatic to fkf1 mutation in the photoperiodic regulation of flowering. COP1 activity requires the formation of a hetero-tetramer with SUPPRESSOR OF PHYA-105 (SPA1), [(COP1)2(SPA1)2]. Light-activated FKF1 has an increased binding capacity for COP1, forming a FKF1-COP1 hetero-dimer, and inhibiting COP1 homo-dimerization at its coiled-coil (CC) domain. Mutations in the CC domain result in poor COP1 dimerization and misregulation of photoperiodic floral induction. We propose that FKF1 represses COP1 activity by inhibiting COP1 dimerization in the late afternoon under long-day conditions, resulting in early flowering. [BMB Reports 2018; 51(4): 163-164].


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ritmo Circadiano , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Luz , Magnoliopsida/genética , Fotoperíodo , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases
13.
Nat Commun ; 9(1): 553, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29396394

RESUMO

The previously published version of this Article contained errors in Figure 5. In panel c, the second and fourth blot images were incorrectly labeled 'α-Myc' and should have been labelled 'α-HA'. These errors have been corrected in both the PDF and HTML versions of the Article.

14.
Nat Commun ; 8(1): 2259, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29273730

RESUMO

In Arabidopsis thaliana, CONSTANS (CO) plays an essential role in the regulation of photoperiodic flowering under long-day conditions. CO protein is stable only in the afternoon of long days, when it induces the expression of FLOWERING LOCUS T (FT), which promotes flowering. The blue-light photoreceptor FLAVIN-BINDING, KELCH REPEAT, F-BOX1 (FKF1) interacts with CO and stabilizes it by an unknown mechanism. Here, we provide genetic and biochemical evidence that FKF1 inhibits CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1)-dependent CO degradation. Light-activated FKF1 has no apparent effect on COP1 stability but can interact with and negatively regulate COP1. We show that FKF1 can inhibit COP1 homo-dimerization. Mutation of the coiled-coil domain in COP1, which prevents dimer formation, impairs COP1 function in coordinating flowering time. Based on these results, we propose a model whereby the light- and day length-dependent interaction between FKF1 and COP1 controls CO stability to regulate flowering time.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação a DNA/metabolismo , Flores/genética , Luz , Fotoperíodo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Arabidopsis , Dimerização , Mutação , Plantas Geneticamente Modificadas , Ubiquitina-Proteína Ligases/metabolismo
15.
Folia Microbiol (Praha) ; 62(2): 127-138, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27787755

RESUMO

The present study was performed to evaluate the antibacterial activities of an antimicrobial peptide (CSpK14) and the synergies thereof with ß-lactams against vancomycin-resistant Staphylococcus aureus (VRSA) and Enterococci (VRE). Our strain was isolated from fermented food (kimchi), which is 99.79 % homologous with Bacillus amyloliquefaciens subsp. plantarum FZB42(T). CSpK14 was purified to homogeneity by diammonium sulfate precipitation, concentration, dialysis, and followed by two-stage chromatographic separation, i.e., Sepharose Cl-6B and Sephadex G-25 chromatography, and had a molar mass of ~4.6 kDa via Tricine SDS-PAGE and in situ examination. It was stable at pH 6.0-11.5 and temperature up to 80 °C. In addition, it was also stable with various metal ions, solvents, and proteases. The N-terminal amino acid sequence was H-Y-D-P-G-D-D-S-G-N-T-G and did not show any significant homology with reported peptides. However, it shows some degrees of identity with alpha-2-macroglobulin and ligand-gated channel protein from different microorganisms. CSpK14 significantly reduced the minimum inhibitory concentrations (MICs) of ß-lactams and had no effect on non-ß-lactams against VRSA and VRE. MICs of CSpK14/oxacillin and CSpK14/ampicillin were reduced by 8- to 64-fold and 2- to 16-fold, respectively. The time killing assay between CSpK14/oxacillin (2.29-2.37 Δlog10CFU/mL at 24 h) and CSpK14/ampicillin (2.30-2.38 Δlog10CFU/mL at 24 h) being >2-fold and fractional inhibitory concentration index ˂0.5 revealed synergy. Furthermore, the biofilms formed by VRSA and VRE were reduced completely. CSpK14 was simple to purify, had low molecular mass, was stable over a wide pH range or tested chemicals, had broad inhibitory spectrum, and possessed potent synergistic antimicrobial-antibiofilm properties. CSpK14 synergistically enhanced the efficacy of ß-lactams and is therefore suitable for combination therapy.


Assuntos
Ampicilina/farmacologia , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bacillus amyloliquefaciens/metabolismo , Oxacilina/farmacologia , Sequência de Aminoácidos , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/biossíntese , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Bacillus amyloliquefaciens/classificação , Bacillus amyloliquefaciens/imunologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Cromatografia por Troca Iônica , Sinergismo Farmacológico , Quimioterapia Combinada , Testes de Sensibilidade Microbiana , Filogenia , Estabilidade Proteica , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Resistência a Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/crescimento & desenvolvimento
16.
Langmuir ; 32(36): 9223-8, 2016 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-27584798

RESUMO

We report stimuli-triggered fabrication of polymersomes from water-in-oil-in-water (W/O/W) multiple double emulsion droplets and the dual-stimuli (temperature and UV) responsive behavior of corresponding polymersomes. The polymersome comprises Tween20, cholesterol, and poly(styrene)-block-poly(N-isopropylacrylamide-co-spironaphthoxazine methacryloyl), i.e., PS-b-P(NIPAAm-co-SPO), synthesized by stepwise reversible addition-fragmentation chain transfer (RAFT) polymerization. Amphiphilic PS-b-P(NIPAAm-co-SPO) copolymer forms micelles in water above the critical micelle concentration (CMC) of 0.7 g/L at 23 °C. The micelles show a temperature-driven aggregation among the micelles above 30.6 °C, confirmed by a decrease in UV-vis transmittance. The micelles also show a color change without colloidal instability under 365 nm UV at room temperature. PS-b-P(NIPAAm-co-SPO) plays not only a role of the polymeric surfactant in the preparation of W/O/W multiple double emulsions but also an important role in the stimuli-triggered transformation from multi- to single-core double emulsion droplets under heat and UV light irradiation. It was found that the morphological transformation of W/O/W multiple double emulsions by UV irradiation was much faster than temperature change. Dual-responsive polymersomes were simply prepared after solvent removal and they exhibit stable and reversible size and color variations under temperature and UV-visible changes, respectively.

17.
Ann Dermatol ; 28(2): 237-41, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27081273

RESUMO

Onychomatricoma is a rare tumor of the nail matrix. Until now, few cases of onychomatricoma have been reported in the literature. Immunohistochemically, CD10, a marker of the onychodermis, is expressed in the stroma of the onychomatricoma. In the present case, a 27-year-old woman presented with an 8-year history of a yellowish, thickened, and overcurved nail plate of the right index finger, mimicking onychomycosis. She had been treated for 4 years with antifungal agents by general physicians, without improvement. The nail was surgically removed, and the tumor at the nail matrix was excised. The nail plate continued to grow in the 2 months after the excision. This is a case of onychomatricoma in South Korea, which was initially misdiagnosed as onychomycosis. In addition, we present a review of the literature regarding clinical, sonographic, and histological features, differential diagnoses, and treatment of onychomatricoma.

18.
Arch Pharm Res ; 39(3): 429-36, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26849878

RESUMO

The salicylic acid derivative 4-tert-butylphenyl salicylate (4-TBPS) possesses anti-inflammatory activity. We demonstrated this and elucidated the mechanisms involved by using the lipopolysaccharide-stimulated Raw 264.7 mouse macrophage model. The 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, western blot, enzyme-linked immunosorbent assay, and reverse transcriptase-polymerase chain reaction were performed to explore 4-TBPS anti-inflammatory activity. We found that 4-TBPS decreased nitric oxide production without cytotoxic effects on macrophages and reduced expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 in a dose-dependent manner. Additionally, mRNA expressions of iNOS and COX-2 significantly reduced, with concentrations between 1 and 15 µg/ml. Furthermore, 4-TBPS significantly inhibited the production of pro-inflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin- (IL)-1ß, and IL-6. Moreover, mRNA gene expression of TNF-α, IL-1ß, and IL-6 was attenuated in a dose-dependent manner. 4-TBPS potently inhibited translocation of nuclear factor-κB (NF-κB) into the nucleus by degrading IκB kinase (IκBα) following its phosphorylation, thereby causing NF-κB to remain inactive. Collectively, our data indicate that 4-TBPS significantly (p < 0.01) targets the inflammatory response of macrophages via inhibition of iNOS, COX-2, TNF-α, IL-1ß, and IL-6 through downregulation of the NF-κB pathway. This indicates that 4-TBPS may have therapeutic potential in inflammatory disorders.


Assuntos
NF-kappa B/metabolismo , Salicilatos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo , Quinase I-kappa B/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fosforilação , Fator de Necrose Tumoral alfa/metabolismo
19.
Nat Commun ; 6: 8041, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26314500

RESUMO

YUCCA (YUC) proteins constitute a family of flavin monooxygenases (FMOs), with an important role in auxin (IAA) biosynthesis. Here we report that Arabidopsis plants overexpressing YUC6 display enhanced IAA-related phenotypes and exhibit improved drought stress tolerance, low rate of water loss and controlled ROS accumulation under drought and oxidative stresses. Co-overexpression of an IAA-conjugating enzyme reduces IAA levels but drought stress tolerance is unaffected, indicating that the stress-related phenotype is not based on IAA overproduction. YUC6 contains a previously unrecognized FAD- and NADPH-dependent thiol-reductase activity (TR) that overlaps with the FMO domain involved in IAA biosynthesis. Mutation of a conserved cysteine residue (Cys-85) preserves FMO but suppresses TR activity and stress tolerance, whereas mutating the FAD- and NADPH-binding sites, that are common to TR and FMO domains, abolishes all outputs. We provide a paradigm for a single protein playing a dual role, regulating plant development and conveying stress defence responses.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Secas , Ácidos Indolacéticos/metabolismo , Oxigenases de Função Mista/genética , Estresse Oxidativo/genética , Oxirredutases/genética , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/genética , Compostos de Sulfidrila/metabolismo , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista/metabolismo , Mutação , Oxirredutases/metabolismo , Fenótipo
20.
Pediatr Dermatol ; 32(1): 132-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-23869595

RESUMO

Soft tissue chondroma is a rare benign tumor of the cartilage. It occurs commonly in distal extremities of middle-aged patients. It is usually asymptomatic and grows slowly, making early diagnosis difficult. We report a 10-year-old patient with a 1-year history of a subungual soft tissue chondroma on her left fifth finger. The lesion arose from nail bed and distal nail matrix, resulting in nail dystrophy. Magnetic resonance imaging revealed a soft tissue tumor in the subungual region and soft tissue chondroma was diagnosed, based on histopathologic findings. Dermatologists should consider soft tissue chondroma in the differential diagnosis of subungual tumors of children.


Assuntos
Condroma/diagnóstico , Doenças da Unha/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Criança , Condroma/cirurgia , Feminino , Dedos , Humanos , Doenças da Unha/cirurgia , Neoplasias de Tecidos Moles/cirurgia
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