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1.
Polymers (Basel) ; 16(8)2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38675090

RESUMEN

This study presents the synthesis and characterization of non-isocyanate polyurethanes (NIPU) derived from the copolymerization of cyclic-carbonated soybean oil (CSBO) and cyclic carbonate (CC)-terminated poly(ether carbonate) (RCC). Using a double-metal cyanide catalyst, poly(ether carbonate) polyol was first synthesized through the copolymerization of carbon dioxide and propylene oxide. The terminal hydroxyl group was then subjected to a substitution reaction with a five-membered CC group using glycerol-1,2-carbonate and oxalyl chloride, yielding RCC. Attempts to prepare NIPU solely using RCC and diamine were unsuccessful, possibly due to the low CC functionality and the aminolysis of RCC's linear carbonate repeating units. However, when combined with CSBO, solid NIPUs were successfully obtained, exhibiting good thermal stability along with enhanced mechanical properties compared to conventional CSBO-based NIPU formulations. Overall, this study underscores the potential of leveraging renewable resources and carbon capture technologies to develop sustainable NIPUs with tailored properties, thereby expanding their range of applications.

2.
Nanotechnology ; 31(35): 355702, 2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32403092

RESUMEN

Tin disulfide (SnS2) has emerged as a promising two-dimensional (2D) material due to its excellent electrical and optical properties. However, research into 2D SnS2 has mainly focused on its synthesis procedures and applications; its stability to humidity and temperature has yet to be studied. In this work, 2D SnS2 thin films were grown by atomic layer deposition (ALD) and characterized by various tools, such as x-ray diffraction, Raman analysis, and transmission electron spectroscopy. Characterization reveals that ALD-grown SnS2 thin films are a high-quality 2D material. After characterization, a four-inch-wafer-scale uniformity test was performed by Raman analysis. Owing to the quality, large-area growth enabled by the ALD process, 98.72% uniformity was obtained. Finally, we calculated the thermodynamic equations for possible reactions between SnS2 and H2O to theoretically presurmise the oxidation of SnS2 during accelerated humidity and temperature testing. After the accelerated humidity and temperature test, x-ray diffraction, Raman analysis, and Auger electron spectroscopy were performed to check whether SnS2 was oxidized or not. Our data revealed that 2D SnS2 thin films were stable at humid conditions.

3.
Stem Cell Res Ther ; 8(1): 262, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29141662

RESUMEN

BACKGROUND: Adipose tissue-derived mesenchymal stem cells (AT-MSCs) offer potential as a therapeutic option for chronic discogenic low back pain (LBP) because of their immunomodulatory functions and capacity for cartilage differentiation. The goal of this study was to assess the safety and tolerability of a single intradiscal implantation of combined AT-MSCs and hyaluronic acid (HA) derivative in patients with chronic discogenic LBP. METHODS: We performed a single-arm phase I clinical trial with a 12-month follow-up and enrolled 10 eligible chronic LBP patients. Chronic LBP had lasted for more than 3 months with a minimum intensity of 4/10 on a visual analogue scale (VAS) and disability level ≥ 30% on the Oswestry Disability Index (ODI). The 10 patients underwent a single intradiscal injection of combined HA derivative and AT-MSCs at a dose of 2 × 107 cells/disc (n = 5) or 4 × 107 cells/disc (n = 5). Safety and treatment outcomes were evaluated by assessing VAS, ODI, Short Form-36 (SF-36), and imaging (lumbar spine X-ray imaging and MRI) at regular intervals over 1 year. RESULTS: No patients were lost at any point during the 1-year clinical study. We observed no procedure or stem cell-related adverse events or serious adverse events during the 1-year follow-up period. VAS, ODI, and SF-36 scores significantly improved in both groups receiving both low (cases 2, 4, and 5) and high (cases 7, 8, and 9) cell doses, and did not differ significantly between the two groups. Among six patients who achieved significant improvement in VAS, ODI, and SF-36, three patients (cases 4, 8, and 9) were determined to have increased water content based on an increased apparent diffusion coefficient on diffusion MRI. CONCLUSIONS: Combined implantation of AT-MSCs and HA derivative in chronic discogenic LBP is safe and tolerable. However, the efficacy of combined AT-MSCs and HA should be investigated in a randomized controlled trial in a larger population. TRIAL REGISTRATION: ClinicalTrials.gov NCT02338271 . Registered 7 January 2015.


Asunto(s)
Ácido Hialurónico/uso terapéutico , Degeneración del Disco Intervertebral/terapia , Dolor de la Región Lumbar/terapia , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Tejido Adiposo/citología , Tejido Adiposo/fisiología , Adulto , Diferenciación Celular , Enfermedad Crónica , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intralesiones , Disco Intervertebral/efectos de los fármacos , Disco Intervertebral/patología , Disco Intervertebral/fisiopatología , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/fisiopatología , Dolor de la Región Lumbar/patología , Dolor de la Región Lumbar/fisiopatología , Masculino , Células Madre Mesenquimatosas/fisiología , Persona de Mediana Edad , Dimensión del Dolor , Seguridad del Paciente , Trasplante Autólogo , Resultado del Tratamiento , Agua/metabolismo
4.
Immune Netw ; 15(5): 232-40, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26557807

RESUMEN

The triggering receptor expressed on myeloid cells (TREM) family, which is abundantly expressed in myeloid lineage cells, plays a pivotal role in innate and adaptive immune response. In this study, we aimed to identify a novel receptor expressed on hematopoietic stem cells (HSCs) by using in silico bioinformatics and to characterize the identified receptor. We thus found the TREM-like transcript (TLT)-6, a new member of TREM family. TLT-6 has a single immunoglobulin domain in the extracellular region and a long cytoplasmic region containing 2 immunoreceptor tyrosine-based inhibitory motif-like domains. TLT-6 transcript was expressed in HSCs, monocytes and macrophages. TLT-6 protein was up-regulated on the surface of bone marrow-derived and peritoneal macrophages by lipopolysaccharide stimulation. TLT-6 exerted anti-proliferative effects in macrophages. Our results demonstrate that TLT-6 may regulate the activation and proliferation of macrophages.

5.
Nanoscale Res Lett ; 9(1): 330, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25024690

RESUMEN

Thin and long silver nanowires were successfully synthesized using the polyvinylpyrrolidone (PVP)-assisted polyol method in the presence of ionic liquids, tetrapropylammonium chloride and tetrapropylammonium bromide, which served as soft template salts. The first step involved the formation of Ag nanoparticles with a diameter of 40 to 50 nm through the reduction of silver nitrate. At the growing stage, the Ag nanoparticles were converted into thin and long one-dimensional wires, with uniform diameters of 30 ± 3 nm and lengths of up to 50 µm. These Ag nanowires showed an electrical conductivity of 0.3 × 10(5) S/cm, while the sheet resistance of a two-dimensional percolating Ag nanowire network exhibited a value of 20 Ω/sq with an optical transmittance of 93% and a low haze value.

6.
Korean J Intern Med ; 25(4): 415-21, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21179280

RESUMEN

BACKGROUND/AIMS: Fabry disease is an X-linked recessive and progressive disease caused by α-galactosidase A (α-GaL A) deficiency. We sought to assess the prevalence of unrecognized Fabry disease in dialysis-dependent patients and the efficacy of serum globotriaosylceramide (GL3) screening. METHODS: A total of 480 patients of 1,230 patients among 17 clinics were enrolled. Serum GL3 levels were measured by tandem mass spectrometry. Additionally, we studied the association between increased GL3 levels and cardiovascular disease, cerebrovascular disease, or left ventricular hypertrophy. RESULTS: Twenty-nine patients had elevated serum GL3 levels. The α-GaL A activity was determined for the 26 patients with high GL3 levels. The mean α-GaL A activity was 64.6 nmol/hr/mg (reference range, 45 to 85), and no patient was identified with decreased α-GaL A activity. Among the group with high GL3 levels, 15 women had a α-GaL A genetics analysis. No point mutations were discovered among the women with high GL3 levels. No correlation was observed between serum GL3 levels and α-GaL A activity; the Pearson correlation coefficient was 0.01352 (p = 0.9478). No significant correlation was observed between increased GL3 levels and the frequency of cardiovascular disease or cerebrovascular disease. CONCLUSIONS: Fabry disease is very rare disease in patients with end-stage renal disease. Serum GL3 measurements as a screening method for Fabry disease showed a high false-positive rate. Thus, serum GL3 levels determined by tandem mass spectrometry may not be useful as a screening method for Fabry disease in patients with end stage renal disease.


Asunto(s)
Enfermedad de Fabry/diagnóstico , Fallo Renal Crónico/terapia , Diálisis Renal , Trihexosilceramidas/sangre , Adulto , Anciano , Enfermedad de Fabry/sangre , Femenino , Humanos , Fallo Renal Crónico/sangre , Masculino , Persona de Mediana Edad , alfa-Galactosidasa/genética , alfa-Galactosidasa/metabolismo
7.
Intervirology ; 53(2): 83-6, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19955812

RESUMEN

OBJECTIVES: Clevudine has demonstrated antiviral potency in the treatment of naïve chronic hepatitis B patients in pivotal studies. The objectives of this study were to evaluate the safety and efficacy of a 1-year treatment with clevudine in chronic hepatitis B patients. METHODS: This is a post-marketing surveillance using case report forms which were submitted to the health authorities. RESULTS: Analysis of individual data showed that hepatitis B virus (HBV) DNA after a 1-year treatment was <141,500 copies/ml in 96% of hepatitis B e antigen (HBeAg)-positive and 100% of HBeAg-negative patients. The proportion of patients with HBV DNA <2,000 copies/ml after a 1-year treatment was 74%: 71% of HBeAg-positive and 93% of HBeAg-negative patients. Most of the patients with HBV DNA below the detection limit with each assay at week 24 showed sustained viral suppression up to week 48. The proportion of patients who showed normal alanine aminotransferase at week 48 was 86% in HBeAg-positive patients and 87% in HBeAg-negative patients. The rates of HBeAg-loss were 21%. Two patients showed viral breakthrough during treatment. CONCLUSION: Clevudine monotherapy demonstrates potent antiviral activity as well as biochemical and serological response with a 0.7% rate of viral breakthrough in naïve chronic hepatitis B patients.


Asunto(s)
Antivirales/uso terapéutico , Arabinofuranosil Uracilo/análogos & derivados , Hepatitis B Crónica/tratamiento farmacológico , Alanina Transaminasa/sangre , Antivirales/efectos adversos , Arabinofuranosil Uracilo/efectos adversos , Arabinofuranosil Uracilo/uso terapéutico , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Plasma/virología , Insuficiencia del Tratamiento , Resultado del Tratamiento , Carga Viral
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