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1.
BMC Public Health ; 17(1): 844, 2017 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070021

RESUMO

BACKGROUND: The purpose of this study was to investigate the relationship between multiple chronic diseases and depressive symptoms in middle-aged and elderly populations. METHODS: This study was performed using the 2009 Korean Community Health Survey, which targeted adults over the age of 40 (N = 156,747 participants, 88,749 aged 40-59 years and 67,998 aged ≥60 years). The Korean version of the Center for Epidemiologic Studies Depression Scale (CES-D-K) was used as the measurement tool for depressive symptoms (CES-D-K score over 16). Multiple chronic diseases were defined as the concurrent presence of two or more chronic diseases. RESULTS: The prevalence and risk ratios (RRs) of experiencing depressive symptoms increased in the presence of multiple chronic diseases and with the number of comorbidities. The RRs of experiencing depressive symptoms according to the presence of multiple chronic diseases were higher in the middle-aged population (adjusted RR, 1.939, 95% confidence limits (CL), 1.82-2.06) than in the elderly population (adjusted RR, 1.620, 95% CL, 1.55-1.69). In particular, middle-aged women who suffer from 4 or more chronic diseases have the highest RR (adjusted RR, 4.985, 95% CL, 4.13-6.03) for depressive symptoms. CONCLUSIONS: Multiple chronic diseases are closely associated with depressive symptoms in middle-aged and elderly populations. Given the mutual relationship between multiple chronic diseases and depressive symptoms, attention to and the assessment of depressive symptoms are needed in people with multiple chronic diseases.


Assuntos
Depressão/epidemiologia , Múltiplas Afecções Crônicas/epidemiologia , Adulto , Idoso , Comorbidade , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Múltiplas Afecções Crônicas/psicologia , Razão de Chances , Prevalência , República da Coreia/epidemiologia
2.
Mol Pharm ; 11(8): 2845-54, 2014 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-24978295

RESUMO

Many of the reported arginine-rich cell-penetrating peptides (CPPs) for the enhanced delivery of drugs are linear peptides composed of more than seven arginine residues to retain the cell penetration properties. Herein, we synthesized a class of nine polyarginine peptides containing 5 and 6 arginines, namely, R5 and R6. We further explored the effect of acylation with long chain fatty acids (i.e., octanoic acid, dodecanoic acid, and hexadecanoic acid) and cyclization on the cell penetrating properties of the peptides. The fluorescence-labeled acylated cyclic peptide dodecanoyl-[R5] and linear peptide dodecanoyl-(R5) showed approximately 13.7- and 10.2-fold higher cellular uptake than that of control 5,6-carboxyfluorescein, respectively. The mechanism of the peptide internalization into cells was found to be energy-dependent endocytosis. Dodecanoyl-[R5] and dodecanoyl-[R6] enhanced the intracellular uptake of a fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F'-GpYEEI) in human ovarian cancer cells (SK-OV-3) by 3.4-fold and 5.5-fold, respectively, as shown by flow cytometry. The cellular uptake of F'-GpYEEI in the presence of hexadecanoyl-[R5] was 9.3- and 6.0-fold higher than that in the presence of octanoyl-[R5] and dodecanoyl-[R5], respectively. Dodecanoyl-[R5] enhanced the cellular uptake of the phosphopeptide by 1.4-2.5-fold higher than the corresponding linear peptide dodecanoyl-(R5) and those of representative CPPs, such as hepta-arginine (CR7) and TAT peptide. These results showed that a combination of acylation by long chain fatty acids and cyclization on short arginine-containing peptides can improve their cell-penetrating property, possibly through efficient interaction of rigid positively charged R and hydrophobic dodecanoyl moiety with the corresponding residues in the cell membrane phospholipids.


Assuntos
Ácidos Graxos/química , Peptídeos/farmacocinética , Acilação , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Proliferação de Células , Peptídeos Penetradores de Células , Ciclização , Portadores de Fármacos/química , Endocitose , Feminino , Fluoresceínas/química , Células HEK293 , Humanos , Microscopia Confocal , Neoplasias Ovarianas/tratamento farmacológico , Peptídeos/química , Peptídeos Cíclicos/química , Fosfolipídeos/química , Fosfopeptídeos/química , Triptofano/química
3.
Mol Pharm ; 11(10): 3631-41, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25184366

RESUMO

A cyclic peptide composed of five tryptophan, four arginine, and one cysteine [W5R4C] was synthesized. The peptide was evaluated for generating cyclic peptide-capped selenium nanoparticles (CP-SeNPs) in situ. A physical mixing of the cyclic peptide with SeO3(-2) solution in water generated [W5R4C]-SeNPs via the combination of reducing and capping properties of amino acids in the peptide structure. Transmission electron microscopy (TEM) images showed that [W5R4C]-SeNPs were in the size range of 110-150 nm. Flow cytometry data revealed that a fluorescence-labeled phosphopeptide (F'-PEpYLGLD, where F' = fluorescein) and an anticancer drug (F'-dasatinib) exhibited approximately 25- and 9-times higher cellular uptake in the presence of [W5R4C]-SeNPs than those of F'-PEpYLGLD and dasatinib alone in human leukemia (CCRF-CEM) cells after 2 h of incubation, respectively. Confocal microscopy also exhibited higher cellular delivery of F'-PEpYLGLD and F'-dasatinib in the presence of [W5R4C]-SeNPs compared to the parent fluorescence-labeled drug alone in human ovarian adenocarcinoma (SK-OV-3) cells after 2 h of incubation at 37 °C. The antiproliferative activities of several anticancer drugs doxorubicin, gemcitabine, clofarabine, etoposide, camptothecin, irinotecan, epirubicin, fludarabine, dasatinib, and paclitaxel were improved in the presence of [W5R4C]-SeNPs (50 µM) by 38%, 49%, 36%, 36%, 31%, 30%, 30%, 28%, 24%, and 17%, respectively, after 48 h incubation in SK-OV-3 cells. The results indicate that CP-SeNPs can be potentially used as nanosized delivery tools for negatively charged biomolecules and anticancer drugs.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Nanopartículas Metálicas/química , Peptídeos Cíclicos/química , Selênio/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Humanos , Microscopia Eletrônica de Transmissão
4.
Mol Pharm ; 11(10): 3528-36, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25157458

RESUMO

Multidrug-resistant pathogens have become a major public health concern. There is a great need for the development of novel antibiotics with alternative mechanisms of action for the treatment of life-threatening bacterial infections. Antimicrobial peptides, a major class of antibacterial agents, share amphiphilicity and cationic structural properties with cell-penetrating peptides (CPPs). Herein, several amphiphilic cyclic CPPs and their analogues were synthesized and exhibited potent antibacterial activities against multidrug-resistant pathogens. Among all the peptides, cyclic peptide [R4W4] (1) showed the most potent antibacterial activity against methicillin-resistant Staphylococcus aureus [MRSA, exhibiting a minimal inhibitory concentration (MIC) of 2.67 µg/mL]. Cyclic [R4W4] and the linear counterpart R4W4 exhibited MIC values of 42.8 and 21.7 µg/mL, respectively, against Pseudomonas aeruginosa. In eukaryotic cells, peptide 1 exhibited the expected cell penetrating properties and showed >84% cell viability at a concentration of 15 µM (20.5 µg/mL) in three different human cell lines. Twenty-four hour time-kill studies evaluating [R4W4] with 2 times the MIC in combination with tetracycline demonstrated bactericidal activity at 4 and 8 times the MIC of tetracycline against MRSA (MIC = 0.5 µg/mL) and 2-8 times the MIC against Escherichia coli (MIC = 2 µg/mL). This study suggests that when amphiphilic cyclic CPPs are used in combination with an antibiotic such as tetracycline, they provide significant benefit against multidrug-resistant pathogens when compared with the antibiotic alone.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Penetradores de Células/farmacologia , Antibacterianos/efeitos adversos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/química , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos
5.
Tetrahedron Lett ; 55(12): 1983-1986, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24791029

RESUMO

A number of 5'-O-dicarboxylic fatty acyl monoester derivatives of 3'-azido-3'-deoxythymidine (zidovudine, AZT), 2',3'-didehydro-2',3'-dideoxythymidine (stavudine, d4T), and 3'-fluoro-3'-deoxythymidine (alovudine, FLT) were synthesized to improve the lipophilicity and potentially the cellular delivery of parent polar 2', 3'-dideoxynucleoside (ddN) analogues. The compounds were evaluated for their anti-HIV activity. Three different fatty acids with varying chain length of suberic acid (octanedioic acid), sebacic acid (decanedioic acid), and dodecanedioic acid were used for the conjugation with the nucleosides. The compounds were evaluated for anti-HIV activity and cytotoxicity. All dicarboxylic ester conjugates of nucleosides exhibited significantly higher anti-HIV activity than that of the corresponding parent nucleoside analogs. Among all the tested conjugates, 5'-O-suberate derivative of AZT (EC50 = 0.10 nM) was found to be the most potent compound and showed 80-fold higher anti-HIV activity than AZT without any significant toxicity (TC50 > 500 nM).

6.
Tetrahedron Lett ; 55(2): 373-375, 2014 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-24453382

RESUMO

Several novel N-(9-oxo-9H-xanthen-4-yl)benzenesulfonamides derivatives were prepared as potential antiproliferative agents. The in vitro antiproliferative activity of the synthesized compounds was investigated against a panel of tumor cell lines including breast cancer cell lines (MDA-MB-231, T-47D) and neuroblastoma cell line (SK-N-MC) using MTT colorimetric assay. Etoposide, a well-known anticancer drug, was used as a positive standard drug. Among synthesized compounds, 4-methoxy-N-(9-oxo-9H-xanthen-4-yl)benzenesulfonamide (5i) showed the highest antiproliferative activity against MDA-MB-231, T-47D, and SK-N-MC cells. Furthermore, pentafluoro derivatives 5a and 6a exhibited higher antiproliferative activity than doxorubicin against human leukemia cell line (CCRF-CEM) and breast adenocarcinoma (MDA-MB-468) cells. Structure-activity relationship studies revealed that xanthone benzenesulfonamide hybrid compounds can be used for development of new lead anticancer agents.

7.
J Korean Med Sci ; 29(1): 12-22, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24431900

RESUMO

Although pharmacological treatment constitutes the main therapeutic approach for depression, non-pharmacological treatments (self-care or psychotherapeutic approach) are usually regarded as more essential therapeutic approaches in clinical practice. However, there have been few clinical practice guidelines concerning self-care or psychotherapy in the management of depression. This study introduces the 'Evidence-Based, Non-Pharmacological Treatment Guideline for Depression in Korea.' For the first time, a guideline was developed for non-pharmacological treatments for Korean adults with mild-to-moderate depression. The guideline development process consisted of establishing several key questions related to non-pharmacologic treatments of depression, searching the literature for studies which answer these questions, assessing the evidence level of each selected study, drawing up draft recommendation, and peer review. The Scottish Intercollegiate Guidelines Network grading system was used to evaluate the quality of evidence. As a result of this process, the guideline recommends exercise therapy, bibliotherapy, cognitive behavior therapy, short-term psychodynamic supportive psychotherapy, and interpersonal psychotherapy as the non-pharmacological treatments for adult patients with mild-to-moderate depression in Korea. Hence, it is necessary to develop specific methodologies for several non-pharmacological treatment for Korean adults with depression.


Assuntos
Biblioterapia/métodos , Terapia Cognitivo-Comportamental/métodos , Terapia Combinada/métodos , Depressão/tratamento farmacológico , Depressão/terapia , Adulto , Protocolos Clínicos , Depressão/psicologia , Terapia por Exercício , Humanos , Placebos/uso terapêutico , República da Coreia , Inquéritos e Questionários
8.
Mol Pharm ; 10(5): 2008-20, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23537165

RESUMO

Phosphopeptides are valuable reagent probes for studying protein-protein and protein-ligand interactions. The cellular delivery of phosphopeptides is challenging because of the presence of the negatively charged phosphate group. The cellular uptake of a number of fluorescent-labeled phosphopeptides, including F'-GpYLPQTV, F'-NEpYTARQ, F'-AEEEIYGEFEAKKKK, F'-PEpYLGLD, F'-pYVNVQN-NH2, and F'-GpYEEI (F' = fluorescein), was evaluated in the presence or absence of a [WR]4, a cyclic peptide containing alternative arginine (R) and tryptophan (W) residues, in human leukemia cells (CCRF-CEM) after 2 h incubation using flow cytometry. [WR]4 improved significantly the cellular uptake of all phosphopeptides. PEpYLGLD is a sequence that mimics the pTyr1246 of ErbB2 that is responsible for binding to the Chk SH2 domain. The cellular uptake of F'-PEpYLGLD was enhanced dramatically by 27-fold in the presence of [WR]4 and was found to be time-dependent. Confocal microscopy of a mixture of F'-PEpYLGLD and [WR]4 in live cells exhibited intracellular localization and significantly higher cellular uptake compared to that of F'-PEpYLGLD alone. Transmission electron microscopy (TEM) and isothermal calorimetry (ITC) were used to study the interaction of PEpYLGLD and [WR]4. TEM results showed that the mixture of PEpYLGLD and [WR]4 formed noncircular nanosized structures with width and height of 125 and 60 nm, respectively. ITC binding studies confirmed the interaction between [WR]4 and PEpYLGLD. The binding isotherm curves, derived from sequential binding models, showed an exothermic interaction driven by entropy. These studies suggest that amphiphilic peptide [WR]4 can be used as a cellular delivery tool of cell-impermeable negatively charged phosphopeptides.


Assuntos
Fosfopeptídeos/administração & dosagem , Fosfopeptídeos/química , Sequência de Aminoácidos , Arginina/química , Transporte Biológico Ativo , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Corantes Fluorescentes/química , Humanos , Estrutura Molecular , Peptídeos Cíclicos/química , Fosfopeptídeos/farmacocinética , Domínios e Motivos de Interação entre Proteínas , Tensoativos/química , Termodinâmica , Triptofano/química
9.
Mol Pharm ; 10(8): 3137-51, 2013 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-23834324

RESUMO

Gold nanoparticles (AuNPs) were synthesized in situ in a green and rapid method from the reaction of reducing linear and cyclic peptides containing tryptophan and lysine residues, (KW)5 and cyclic [KW]5, with an aqueous solution of HAuCl4 and were evaluated as cellular nanodrug delivery systems. The cyclic or linear nature of the peptide was found to determine the morphology and size of the formed peptide-AuNPs and their in vitro molecular transporting efficiency. While cyclic [KW]5-AuNPs formed sponge-like agglomerates, linear (KW)5-AuNPs demonstrated ball-shaped structures. A comparative flow cytometry study showed that the cellular uptake of fluorescence-labeled anti-HIV drugs (emtricitabine (FTC) and lamivudine (3TC)) in human leukemia (CCRF-CEM) cells, and a negatively charged cell-impermeable phosphopeptide (GpYEEI) in human ovarian adecarcinoma (SK-OV-3) cells was significantly higher in the presence of cyclic [KW]5-AuNPs than that of linear (KW)5-AuNPs, parent cyclic [KW]5, and linear (KW)5 peptides. For example, the cellular uptake of F'-GpYEEI was enhanced 12.8-fold by c[KW]5-AuNPs. Confocal microscopy revealed the localization of fluorescence-labeled-3TC in the presence of c[KW]5-AuNPs mostly in nucleus in SK-OV-3 cells after 1 h. On the other hand, l(KW)5-AuNPs delivered fluorescence-labeled-3TC in cytoplasm. These data suggest that noncell penetrating peptides can be converted to efficient molecular transporters through peptide-capped AuNPs formation.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Peptídeos Cíclicos/química , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/química , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Citometria de Fluxo , Humanos , Nanopartículas Metálicas/ultraestrutura , Microscopia Confocal , Microscopia Eletrônica de Transmissão
10.
Mol Pharm ; 10(12): 4717-27, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24215132

RESUMO

Peptide amphiphiles (PAs) are promising tools for the intracellular delivery of numerous drugs. PAs are known to be biodegradable systems. Here, four PA derivatives containing arginine and lysine conjugated with fatty acyl groups with different chain lengths, namely, PA1: R-K(C14)-R, PA2: R-K(C16)-R, PA3: K(C14)-R-K(C14), and PA4: K(C16)-R-K(C16), where C16 = palmitic acid and C14 = myristic acid, were synthesized through Fmoc chemistry. Flow cytometry studies showed that, among all synthesized PAs, only K(C16)-R-K(C16), PA4 was able to enhance the cellular uptake of a fluorescence-labeled anti-HIV drug 2',3'-dideoxy-3'-thiacythidine (F'-3TC, F' = fluorescein) and a biologically important phosphopeptide (F'-PEpYLGLD) in human leukemia cells (CCRF-CEM) after 2 h incubation. For example, the cellular uptake of F'-3TC and F'-PEpYLGLD was enhanced approximately 7.1- and 12.6-fold in the presence of the PA4 compared to those of the drugs alone. Confocal microscopy of F'-3TC and F'-PEpYLGLD loaded PA4 in live cells showed significantly higher intracellular localization than the drug alone in human ovarian cells (SK-OV-3) after 2 h incubation. The high-performance liquid chromatography (HPLC) results showed that loading of Dox by the peptide amphiphile was 56% after 24 h. The loaded Dox was released (34%) within 48 h intracellularly. The circular dichrosim (CD) results exhibited that the secondary structure of the peptide was changed upon interactions with Dox. Mechanistic studies revealed that endocytosis is the major pathway of the internalization. These studies suggest that PAs containing the appropriate sequence of amino acids, chain length, charge, and hydrophobicity can be used as cellular delivery tools for transporting drugs and biomolecules.


Assuntos
Arginina/química , Arginina/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Transporte Biológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Células HCT116 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lisina/química , Estrutura Secundária de Proteína
11.
Soft Matter ; 9(39)2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24187575

RESUMO

A number of cyclic peptides including [FR]4, [FK]4, [WR]4, [CR]4, [AK]4, and [WK]n (n = 3-5) containing L-amino acids were produced using solid-phase peptide synthesis. We hypothesized that an optimal balance of hydrophobicity and charge could generate self-assembled nanostructures in aqueous solution by intramolecular and/or intermolecular interactions. Among all the designed peptides, [WR]n (n = 3-5) generated self-assembled vesicle-like nanostructures at room temperature as shown by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and/or dynamic light scattering (DLS). This class of peptides represents the first report of surfactant-like cyclic peptides that self-assemble into nanostructures. A plausible mechanistic insight into the self-assembly of [WR]5 was obtained by molecular modeling studies. Modified [WR]5 analogues, such as [WMeR]5, [WR(Me)2]5, [WMeR(Me)2]5, and [WdR]5, exhibited different morphologies to [WR]5 as shown by TEM observations. [WR]5 exhibited a significant stabilizing effect for generated silver nanoparticles and glyceraldehyde-3-phosphate dehydrogenase activity. These studies established a new class of surfactant-like cyclic peptides that self-assembled into nanostructures and could have potential applications for the stabilization of silver nanoparticles and protein biomolecules.

12.
Hand Surg Rehabil ; 41(1): 85-89, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34838749

RESUMO

The von Frey filament test (vF) is a mainstay of clinical examination. However, its results can be affected by touch speed and other potentially confounding factors. Moreover, the differences between two adjacent filament levels are too large to detect subtle changes. Active vF (AvF) was developed to induce in-depth sensory change. The present study hypothesized that AvF produces different patterns of fingertip sensation; consequently, it could be used as a new assessment tool for neural impairment. The aim of the study was to provide preliminary normative comparative vF and AvF data. This study prospectively examined 32 healthy participants, using AvF and vF. The index and the fifth finger volar pad were examined using AvF and vF, without visual stimulation. The correlation between AvF and vF measurements was evaluated. In addition, differences according to innervation zone, right versus left hand, and gender, and the correlation between AvF values and subjects' age were analyzed. Mean AvF value was significantly higher and had greater variance than vF (111.3 ± 46.9 vs. 24.1 ± 9.8; P < 0.01). The Spearman correlation coefficient between AvF and vF was 0.341. Values were similar in the index and fifth fingers and right and left hands. However, values were significantly different between women and men. The correlation between age and AvF values was 0.259. AvF provided more precise values, with continuous units for tactile sensation, excluding tester-dependent factors. Furthermore, AvF and vF values may not be correlated.


Assuntos
Mãos , Tato , Feminino , Dedos/inervação , Humanos , Masculino , Tato/fisiologia
13.
ACS Omega ; 6(32): 21043-21058, 2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34423212

RESUMO

The natural gas combined cycle (NGCC) is the most popular and efficient fossil fuel power plant; however, integrating a carbon capture system reduces its performance efficiency. The demand to reduce the carbon capture cost and improve eco-friendliness drives the development of alternatives. In this study, four alternative NGCC-based process schemes were designed: NGCC with amine carbon capture as a base configuration and NGCCs with three different chemical looping combustion (CLC) configurations. Detailed heat and material balances were evaluated for all four cases using the PRO/II simulation package. A comparative analysis of the gross and net power, plant efficiency, and carbon capture efficiency, which are imperative to optimizing the process configuration, was conducted for all of the proposed cases. All NGCC-CLC processes could produce higher net power than NGCC-MEA because the amine regenerator consumes a high amount of power in its operation. In the condition using an equal amount of natural gas supply, NGCC-CLC configurations using excess air could produce a net power of 510.1 MW with a plant efficiency of 44.35%. The excess air fed in both cases enabled the turbine to generate more power. NGCC-CLC using excess air with steam turbine integration has an investment cost of 132.9 $/net MWh, an operating cost of 56.7 $/net MWh year, and a levelized cost of electricity of 90.9 $/MWh. In addition, NGCC-CLC with excess air resulted in a carbon capture efficiency of 99.93% under 59.2 $/ton of CO2, which was higher than that of NGCC-MEA with a carbon efficiency of 95.1%. NGCC-CLC using excess air with steam turbine integration is considered as the most efficient process scheme for generating power from natural gas with regard to efficiency, cost, and environmental impact.

14.
ACS Appl Mater Interfaces ; 13(27): 31605-31613, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34192462

RESUMO

Li metal thickness has been considered a key factor in determining the electrochemical performance of Li metal anodes. The use of thin Li metal anodes is a prerequisite for increasing the energy density of Li secondary batteries intended for emerging large-scale electrical applications, such as electric vehicles and energy storage systems. To utilize thin (20 µm thick) Li metal anodes in Li metal secondary batteries, we investigated the synergistic effect of a functional additive (Li nitrate, LiNO3) and a dual-salt electrolyte (DSE) system composed of Li bis(fluorosulfonyl)imide (LiTFSI) and Li bis(oxalate)borate (LiBOB). By controlling the amount of LiNO3 in DSE, we found that DSE containing 0.05 M LiNO3 (DSE-0.05 M LiNO3) significantly improved the electrochemical performance of Li metal anodes. DSE-0.05 M LiNO3 increased the cycling performance by 146.3% [under the conditions of a 1C rate (2.0 mA cm-2), DSE alone maintained 80% of the initial discharge capacity up to the 205th cycle, whereas DSE-0.05 M LiNO3 maintained 80% up to the 300th cycle] and increased the rate capability by 128.2% compared with DSE alone [the rate capability of DSE-0.05 M LiNO3 = 50.4 mAh g-1, and DSE = 39.3 mAh g-1 under 7C rate conditions (14.0 mA cm-2)]. After analyzing the Li metal surface using scanning electron microscopy and X-ray photoelectron spectroscopy, we were able to infer that the stabilized solid electrolyte interphase layer formed by the combination of LiNO3 and the dual salt resulted in a uniform Li deposition during repeated Li plating/stripping processes.

15.
J Korean Med Sci ; 25(9): 1359-63, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20808681

RESUMO

We investigated the availability of motor unit number estimation (MUNE) as a quantitative method to assess the severity and clinical progression of amyotrophic lateral sclerosis (ALS). The 143 ALS patients were evaluated by statistical MUNE and the revised amyotrophic lateral sclerosis functional rating scale (ALSFRS-R). By using mean values of MUNE according to disease duration, regression equation between mean MUNE and disease duration was presented as a formula. The individual MUNE ratio was calculated by dividing individual MUNE value by mean MUNE value. All patients were classified into 2 groups (MUNE ratio <1 vs. MUNE ratio >or=1) according to the MUNE ratio. Comparison between the 2 groups revealed that the patients in MUNE ratio <1 group or MUNE ratio >or=1 group were respectively assigned to rapid progression or slow progression. We recommended informative mean values of MUNE and best regression equation in ALS patients according to disease duration. These values allow us to evaluate the severity and rapidity of progression in ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Neurônios Motores/fisiologia , Potenciais de Ação/fisiologia , Adulto , Idade de Início , Idoso , Esclerose Lateral Amiotrófica/fisiopatologia , Interpretação Estatística de Dados , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/patologia , Fibras Musculares Esqueléticas/fisiologia , Índice de Gravidade de Doença
16.
Ann Otol Rhinol Laryngol ; 117(3): 186-91, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18444478

RESUMO

OBJECTIVES: We describe a case of multiple sclerosis presenting with sequential bilateral hearing loss. METHODS: A 46-year-old woman underwent a series of audiological and neurologic evaluations for sequential bilateral hearing losses that occurred 6 months apart. RESULTS: Initially, the patient suffered from sudden left hearing loss, and magnetic resonance imaging documented an enhancing lesion in the left middle cerebellar peduncle. Six months later, another episode of sudden vertigo, right hearing loss, and right facial palsy developed. Magnetic resonance imaging disclosed a new lesion in the right middle cerebellar peduncle. CONCLUSIONS: Sequential bilateral hearing loss may be a manifestation of multiple sclerosis. In younger patients with sudden hearing loss, multiple sclerosis should be included in the differential diagnosis.


Assuntos
Perda Auditiva Bilateral/etiologia , Esclerose Múltipla/diagnóstico , Potenciais Evocados , Paralisia Facial/etiologia , Feminino , Perda Auditiva Súbita/etiologia , Testes Auditivos , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Exame Neurológico , Nistagmo Patológico/etiologia , Tegmento Mesencefálico/patologia , Vertigem/etiologia
17.
Chem Sci ; 9(15): 3820-3827, 2018 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-29780514

RESUMO

A hydrocarbon stapled peptide based strategy was used to develop an optimized cell penetrating peptide for siRNA delivery. Various stapled peptides, having amphipathic Leu- and Lys-rich regions, were prepared and their cell penetrating potentials were evaluated. One peptide, stEK, was found to have high cell penetration and siRNA delivery abilities at low nanomolar concentrations. In order to improve its ability to promote gene silencing, stEK was modified by replacing several Lys residues with His moieties. The modified peptide, LKH-stEK, was found to facilitate endosomal escape and to display >90% knock-down with 50 nM of a siRNA targeting cyclophilin B in HeLa cells. The results of an in vivo animal wound healing model study demonstrate that LKH-stEK promotes delivery of an siRNA, which targets the connective tissue growth factor, and that this process leads to efficient gene silencing by the siRNA at a nanomolar level in mouse skin.

18.
J Clin Neurosci ; 13(3): 353-5, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16546389

RESUMO

Several reports from Western countries suggest differences in the clinical features of patients with muscle specific kinase (MuSK) antibody-positive and -negative seronegative myasthenia gravis (MG). We performed the first survey in Korea of MuSK antibodies, studying 23 patients with acetylcholine receptor (AChR)-antibody seronegative MG. MuSK antibodies were present in 4 (26.7%) of 15 generalized seronegative MG patients and none of 8 ocular seronegative MG patients. All four MuSK positive patients were females, with pharyngeal and respiratory muscle weakness, and required immunosuppressive treatment. However, overall disease severity and age at onset was similar to that of MuSK-negative MG and treatment responses were equally good.


Assuntos
Anticorpos/sangue , Miastenia Gravis/sangue , Miastenia Gravis/imunologia , Receptores Proteína Tirosina Quinases/imunologia , Receptores Colinérgicos/imunologia , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Feminino , Humanos , Imunossupressores/farmacologia , Lactente , Coreia (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/terapia , Índice de Gravidade de Doença , Timectomia/métodos
19.
Arch Pharm Res ; 29(6): 520-4, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16833022

RESUMO

Ibuprofen-loaded gelatin microcapsule, a solid form of microcapsules simultaneously containing ethanol and ibuprofen in water-soluble gelatin shell was previously reported to improve the dissolution of drug. In this study, to retard the initial high dissolution of ibuprofen from gelatin microcapsule, the ibuprofen-loaded cross-linked gelatin microcapsule was prepared by treating an ibuprofen-loaded gelatin microcapsule with glutaraldehyde and its dissolution was evaluated compared to ibuprofen powder and gelatin microcapsule. The ibuprofen-loaded cross-linked microcapsule treated with glutaraldehyde for 10 and 60 sec gave significantly higher dissolution rates than did ibuprofen powder. Furthermore, the dissolution rate of ibuprofen from the cross-linked microcapsule treated for 10 sec was similar to that from gelatin microcapsule. However, the dissolution rate of ibuprofen from the cross-linked microcapsule treated for 60 sec decreased significantly compared to gelatin microcapsule, suggesting that the treatment of gelatin microcapsule with glutaraldehyde for 60 sec could cross-link the gelatin microcapsule. Furthermore, the cross-linking of gelatin microcapsule markedly retarded the release rate of ibuprofen in pH 1.2 simulated gastric fluid compared to gelatin microcapsule. However, the cross-linking of gelatin microcapsule with glutaraldehyde hardly changed the size of gelatin microcapsules, ethanol and ibuprofen contents encapsulated in gelatin microcapsule. Thus, the ibuprofen-loaded cross-linked gelatin microcapsule could retard the initial high dissolution of poorly water-soluble ibuprofen.


Assuntos
Anti-Inflamatórios não Esteroides/química , Reagentes de Ligações Cruzadas/química , Gelatina/química , Glutaral/química , Ibuprofeno/química , Cápsulas , Preparações de Ação Retardada , Composição de Medicamentos/métodos , Tamanho da Partícula , Pós , Solubilidade , Fatores de Tempo
20.
J Invest Dermatol ; 136(11): 2305-2313, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27427487

RESUMO

Connective tissue growth factor (CTGF) is a multifunctional matricellular protein, playing a role as a central mediator in tissue remodeling and fibrosis. A number of reports have shown the pivotal roles of CTGF in the progression of fibrosis, suggesting CTGF as a promising therapeutic target for the treatment of fibrotic disorders including hypertrophic scars and keloids. In this study, we present the development of an interfering RNA molecule that efficiently inhibits the expression of CTGF via RNA interference mechanism both in vitro and in vivo. Chemical modifications were introduced to the asymmetric interfering RNA (asiRNA) backbone structure. The resulting RNA molecule, termed cell-penetrating asiRNA (cp-asiRNA), entered into cells and triggered RNA interference-mediated gene silencing without delivery vehicles. The gene-silencing activity of cp-asiRNA targeting CTGF (cp-asiCTGF) was examined both in vitro and in vivo. Furthermore, the administration of cp-asiCTGF in the rat skin excision wound model efficiently reduced the induction of CTGF and collagens during the wound-healing process. These results suggest that the cp-asiCTGF molecule could be developed into antifibrotic therapeutics such as antiscar drugs.


Assuntos
Cicatriz Hipertrófica/genética , Fator de Crescimento do Tecido Conjuntivo/genética , Regulação da Expressão Gênica , RNA Mensageiro/genética , Animais , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Fator de Crescimento do Tecido Conjuntivo/biossíntese , Modelos Animais de Doenças , Fibroblastos/metabolismo , Fibroblastos/patologia , Imuno-Histoquímica , Masculino , Microscopia Confocal , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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