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1.
Neurospine ; 19(2): 249-261, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35793928

RESUMEN

Curcumin is a polyphenolic chemical derived from the rhizomes of Curcuma longa. It has been used throughout the Indian subcontinent for medicinal purposes, religious events, and regional cuisine. It has various pharmacological benefits owing to its anti-inflammatory and antioxidant properties. Its neuroprotective effects on the brain and peripheral nerves have been demonstrated in several in vivo neuronal tissue studies. Because of these functional properties of curcumin, it is considered to have great potential for use in the treatment of spinal cord injuries (SCIs). Numerous immunopathological and biochemical studies have reported that curcumin can help prevent and alleviate subsequent secondary injuries, such as inflammation, edema, free radical damage, fibrosis, and glial scarring, after a primary SCI. Furthermore, following SCI, curcumin administration resulted in better outcomes of neurological function recovery as per the Basso, Beattie, and Bresnahan locomotor rating scale. However, to date, its utility in treating SCIs has only been reported in laboratories. More studies on its clinical applications are needed in the future for ensuring its bioavailability across the blood-brain barrier and for verifying the safe dose for treating SCIs in humans.

2.
PLoS One ; 16(12): e0260460, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34852015

RESUMEN

OBJECTIVE: The demand for treating degenerative lumbar spinal disease has been increasing, leading to increased utilization of medical resources. Thus, we need to understand how the budget of insurance is currently used. The objective of the present study is to overview the utilization of the National Health Insurance Service (NHIS) by providing the direct insured cost between patients receiving surgery and patients receiving nonsurgical treatment for degenerative lumbar disease. METHODS: The NHIS-National Sample Cohort was utilized to select patients with lumbar disc herniation, spinal stenosis, spondylolisthesis or spondylolysis. A matched cohort study design was used to show direct medical costs of surgery (n = 2,698) and nonsurgical (n = 2,698) cohorts. Non-surgical treatment included medication, physiotherapy, injection, and chiropractic. The monthly costs of the surgery cohort and nonsurgical cohort were presented at initial treatment, posttreatment 1, 3, 6, 9, and 12 months and yearly thereafter for 10 years. RESULTS: The characteristics and matching factors were well-balanced between the matched cohorts. Overall, surgery cohort spent $50.84/patient/month, while the nonsurgical cohort spent $29.34/patient/month (p<0.01). Initially, surgery treatment led to more charge to NHIS ($2,762) than nonsurgical treatment ($180.4) (p<0.01). Compared with the non-surgical cohort, the surgery cohort charged $33/month more for the first 3 months, charged less at 12 months, and charged approximately the same over the course of 10 years. CONCLUSION: Surgical treatment initially led to more government reimbursement than nonsurgical treatment, but the charges during follow-up period were not different. The results of the present study should be interpreted in light of the costs of medical services, indirect costs, societal cost, quality of life and societal willingness to pay in each country. The monetary figures are implied to be actual economic costs but those in the reimbursement system instead reflect reimbursement charges from the government.


Asunto(s)
Costo de Enfermedad , Degeneración del Disco Intervertebral/economía , Estenosis Espinal/economía , Espondilolistesis/economía , Espondilólisis/economía , Adulto , Anciano , Analgesia/economía , Analgesia/estadística & datos numéricos , Terapia por Ejercicio/economía , Terapia por Ejercicio/estadística & datos numéricos , Femenino , Humanos , Degeneración del Disco Intervertebral/cirugía , Degeneración del Disco Intervertebral/terapia , Región Lumbosacra/patología , Masculino , Manipulación Quiropráctica/economía , Manipulación Quiropráctica/estadística & datos numéricos , Persona de Mediana Edad , Procedimientos Ortopédicos/economía , Procedimientos Ortopédicos/estadística & datos numéricos , Estenosis Espinal/cirugía , Estenosis Espinal/terapia , Espondilolistesis/cirugía , Espondilolistesis/terapia , Espondilólisis/cirugía , Espondilólisis/terapia
3.
Spine J ; 19(12): 2025-2039, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31421247

RESUMEN

BACKGROUND CONTEXT: Curcumin has anti-inflammatory and antioxidant activities. OBJECTIVE: This study aimed to investigate the effects of curcumin on the histological changes and functional recovery following spinal cord injury (SCI). STUDY DESIGN: One hundred twenty-eight Sprague-Dawley rats were distributed into a sham, SCI only, SCI-hyperglycemia, and SCI-hyperglycemia-curcumin (200 mg/kg/day, i.p.) groups. METHODS: SCI was induced using a clip at T9-10 and hyperglycemia was induced by streptozotocin (60-70 mg/kg, i.v.). Plasma malondialdehyde levels and superoxide dismutase activity was measured to determine oxidative stress. The activity of macrophages in the spinal cord after SCI was stained by the anti-CD68 antibody (ED-1). The tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 levels were measured by enzyme-linked immunosorbent assay and Western blot was used to verify the levels of mitogen-activated protein kinases and STAT3. The glial fibrillary acidic protein expression was evaluated by immunofluorescence analysis. Functional recovery was assessed according to the Basso, Beattie, and Bresnahan scale and histologic outcome was evaluated by the lesion volume and spared tissue area. RESULTS: Superoxide dismutase activity increased, the malondialdehyde level decreased, and ED-1 macrophage marker level decreased in the SCI-hyperglycemia-curcumin group than in the SCI-hyperglycemia group at 2 weeks after SCI (p<.01). The SCI-hyperglycemia-curcumin group showed a statistically significant reduction in IL-6, IL-8, and TNF-α levels compared with the SCI-hyperglycemia group after SCI. The phosphorylated-extracellular signal-regulated kinase, phosphorylated-JNK, and phospho-p38 levels were significantly lower in the SCI-hypoglycemia-curcumin group than in the SCI-hypoglycemia group. The SCI-hyperglycemia-curcumin group showed a decrease in glial fibrillary acidic protein expression after SCI compared with the SCI-hyperglycemia group. The SCI-hyperglycemia-curcumin group showed a lower lesion volume, higher spared tissue, and better functional recovery than the SCI-hyperglycemia group. CONCLUSIONS: Curcumin may have a potential neuroprotective effect in SCI with hyperglycemia. CLINICAL SIGNIFICANCE: Curcumin decreased the inflammatory response and decreased astrogliosis and improved the functional recovery and histologic outcomes in SCI with hyperglycemia.


Asunto(s)
Antiinflamatorios/uso terapéutico , Curcumina/uso terapéutico , Hiperglucemia/complicaciones , Fármacos Neuroprotectores/uso terapéutico , Traumatismos de la Médula Espinal/tratamiento farmacológico , Animales , Proteína Ácida Fibrilar de la Glía/metabolismo , Interleucina-6/metabolismo , Masculino , Malondialdehído/metabolismo , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Recuperación de la Función , Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/complicaciones , Factor de Necrosis Tumoral alfa/metabolismo
4.
Toxicol Appl Pharmacol ; 370: 93-105, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30876865

RESUMEN

Diabetic nephropathy (DN) is one of the most serious long-term complications of type 2 diabetes (T2D). 4-O-methylhonokiol (MH) is one of the biologically active ingredients extracted from the Magnolia stem bark. In this study, we aim to elucidate whether treatment with MH can ameliorate or slow-down progression of DN in a T2D murine model and, if so, whether the protective response of MH correlates with AMPK-associated anti-oxidant and anti-inflammatory effects. To induce T2D, mice were fed normal diet (ND) or high fat diet (HFD) for 3 months to induce insulin resistance, followed by an intraperitoneal injection of STZ to induce hyperglycemia. Both T2D and control mice received gavage containing vehicle or MH once diabetes onset for 3 months. Once completing 3-month MH treatment, five mice from each group were sacrificed as 3 month time-point. The rest mice in each group were sacrificed 3 months later as 6 month time-point. In T2D mice, the typical DN symptoms were induced as expected, reflected by increased proteinuria, renal lipid accumulation and lipotoxic effects inducing oxidative stress, and inflammatory reactions, and final fibrosis. However, these typical DN changes were significantly prevented by MH treatment for 3 months and even at 3 months post-MH withdrawal. Mechanistically, MH renal-protection from DN may be related to lipid metabolic improvement and oxidative stress attenuation along with increases in AMPK/PGC-1α/CPT1B-mediated fatty acid oxidation and Nrf2/SOD2-mediated anti-oxidative stress. Results showed the preventive effect of MH on the renal oxidative stress and inflammation in DN.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Compuestos de Bifenilo/administración & dosificación , Nefropatías Diabéticas/prevención & control , Ácidos Grasos/metabolismo , Lignanos/administración & dosificación , Factor 2 Relacionado con NF-E2/fisiología , Estrés Oxidativo/efectos de los fármacos , Animales , Antiinflamatorios/administración & dosificación , Antioxidantes/administración & dosificación , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/patología , Dieta Alta en Grasa , Activación Enzimática/efectos de los fármacos , Resistencia a la Insulina , Riñón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Oxidación-Reducción , Fitoterapia
5.
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
6.
Korean J Spine ; 14(2): 35-40, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28704906

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the therapeutic effects of combination therapy with curcumin and alendronate on spine fusion surgery in ovariectomized rats. METHODS: Thirty-two female Sprague-Dawley rats (12 weeks old) underwent bilateral ovariectomy (OVX). Eight weeks after surgery, animals underwent intertransverse spine fusion at L4-5. The rats were randomly distributed amongst 4 groups; untreated OVX group, curcumin administered group, alendronate administered group, and the combination therapy group. At 8 weeks after fusion surgery, the animals were sacrificed and the fusion mass was assessed by manual palpation, radiographic scan, and micro-computed tomographic scan. In addition, mechanical strength was determined by a 3-point bending test. RESULTS: Based on the results of manual palpation testing and 3-dimensional micro-computed tomography scanning, solid bone fusion rate was 50% (4 of 8) in the OVX group, 75% (6 of 8) in the alendronate-only and curcumin-only group, and 87.5% (7 of 8) in the combination therapy group, respectively. The combination therapy group had a higher fusion rate compared with the other treatment groups, though not statistically significantly (p>0.05). And the combination therapy group had a significant increase in fusion volume at 8 weeks after spine fusion surgery compared with curcumin-only group (p=0.039). The 3-point bending test showed that combination therapy group had a significantly greater maximal load value compared to that of curcumin-only group (p=0.024). CONCLUSION: The present study demonstrated that additional treatment of curcumin and alendronate after spine fusion surgery in rat can promote higher fusion volume, and improve bone mechanical strength.

7.
Int J Mol Sci ; 17(10)2016 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-27669240

RESUMEN

Diabetic complications are the major cause of mortality for the patients with diabetes. Oxidative stress and inflammation have been recognized as important contributors for the development of many diabetic complications, such as diabetic nephropathy, hepatopathy, cardiomyopathy, and other cardiovascular diseases. Several studies have established the anti-inflammatory and oxidative roles of bioactive constituents in Magnolia bark, which has been widely used in the traditional herbal medicines in Chinese society. These findings have attracted various scientists to investigate the effect of bioactive constituents in Magnolia bark on diabetic complications. The aim of this review is to present a systematic overview of bioactive constituents in Magnolia bark that induce the prevention of obesity, hyperglycemia, hyperlipidemia, and diabetic complications, including cardiovascular, liver, and kidney.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Nefropatías Diabéticas/prevención & control , Magnolia/química , Extractos Vegetales/uso terapéutico , Enfermedades Cardiovasculares/complicaciones , Diabetes Mellitus/patología , Nefropatías Diabéticas/complicaciones , Humanos , Hiperglucemia/complicaciones , Hiperglucemia/prevención & control , Magnolia/metabolismo , Medicina Tradicional China , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología
8.
Neurol Med Chir (Tokyo) ; 54(5): 387-94, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24477066

RESUMEN

The purpose of this study was investigating the effects of curcumin on the histological changes and functional recovery following spinal cord injury (SCI) in a rat model. Following either sham operation or SCI, 36 male Sprague-Dawley rats were distributed into three groups: sham group, curcumin-treated group, and vehicle-injected group. Locomotor function was assessed according to the Basso, Beattie, and Bresnahan (BBB) scale in rats who had received daily intraperitoneal injections of 200 mg/kg curcumin or an equivalent volume of vehicle for 7 days following SCI. The injured spinal cord was then examined histologically, including quantification of cavitation. BBB scores were significantly higher in rats receiving curcumin than receiving vehicle (P < 0.05). The cavity volume was significantly reduced in the curcumin group as compared to the control group (P = 0.039). Superoxide dismutase (SOD) activity was significantly elevated in the curcumin group as compared to the vehicle group but was not significantly different from the sham group (P < 0.05, P > 0.05, respectively) at one and two weeks after SCI. Malondialdehyde (MDA) levels were significantly elevated in the vehicle group as compared to the sham group (P < 0.05 at 1 and 2 weeks). MDA activity was significantly reduced in the curcumin group at 2 weeks after SCI when compared to the vehicle group (P = 0.004). The numbers of macrophage were significantly decreased in the curcumin group (P = 0.001). This study demonstrated that curcumin enhances early functional recovery after SCI by diminishing cavitation volume, anti-inflammatory reactions, and antioxidant activity.


Asunto(s)
Antiinflamatorios/uso terapéutico , Curcumina/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Fitoterapia , Traumatismos de la Médula Espinal/tratamiento farmacológico , Enfermedad Aguda , Animales , Antiinflamatorios/administración & dosificación , Antioxidantes/uso terapéutico , Curcumina/administración & dosificación , Evaluación Preclínica de Medicamentos , Inyecciones Intraperitoneales , Peroxidación de Lípido/efectos de los fármacos , Locomoción/efectos de los fármacos , Masculino , Malondialdehído/sangre , Fármacos Neuroprotectores/administración & dosificación , Ratas , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal/patología , Superóxido Dismutasa/sangre
9.
J Korean Neurosurg Soc ; 54(6): 461-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24527187

RESUMEN

OBJECTIVE: Although curcumin has a protective effect on bone remodeling, appropriate therapeutic concentrations of curcumin are not well known as therapeutic drugs for osteoporosis. The purpose of this study was to compare the bone sparing effect of treatment of low-dose and high-dose curcumin after ovariectomy in rats. METHODS: Forty female Sprague-Dawley rats underwent either a sham operation (the sham group) or bilateral ovariectomy (OVX). The ovariectomized animals were randomly distributed among three groups; untreated OVX group, low-dose (10 mg/kg) curcumin administered group, and high-dose (50 mg/kg) curcumin group. At 4 and 8 weeks after surgery, serum biochemical markers of bone turnover were analyzed. Bone histomorphometric parameters of the 4th lumbar vertebrae were determined by micro-computed tomography (CT). In addition, mechanical strength was determined by a three-point bending test. RESULTS: High-dose curcumin group showed significantly lower osteocalcin, alkaline phosphatase, and the telopeptide fragment of type I collagen C-terminus concentration at 4 and 8 weeks compared with the untreated OVX group as well as low-dose curcumin group. In the analyses of micro-CT scans of 4th lumbar vertebrae, the high-dose curcumin treated group showed a significant increase in bone mineral densities (p=0.028) and cortical bone mineral densities (p=0.036) compared with the low-dose curcumin treated group. Only high-dose curcumin treated group had a significant increase of mechanical strength compared with the untreated OVX group (p=0.015). CONCLUSION: The present study results demonstrat that a high-dose curcumin has therapeutic advantages over a low-dose curcumin of an antiresorptive effect on bone remodeling and improving bone mechanical strength.

10.
J Korean Neurosurg Soc ; 52(4): 281-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23133713

RESUMEN

OBJECTIVE: To evaluate the effect of calcium supplementation on spinal bone fusion in ovariectomized (OVX) rats. METHODS: Sixteen female Sprague Dawley rats underwent bilateral ovariectomy at 12 weeks of age to induce osteoporosis and were randomly assigned to two groups : control group (n=8) and calcium-supplemented group (OVX-Ca, n=8). Autologous spinal bone fusion surgery was performed on both groups 8 weeks later. After fusion surgery, the OVX-Ca group was supplemented with calcium in drinking water for 8 weeks. Blood was obtained 4 and 8 weeks after fusion surgery. Eight weeks after fusion surgery, the rats were euthanized and the L4-5 spine removed. Bone fusion status and fusion volume were evaluated by manual palpation and three-dimensional computed tomography. RESULTS: The mean fusion volume in the L4-5 spine was significantly greater in the OVX-Ca group (71.80±8.06 mm(3)) than in controls (35.34±8.24 mm(3)) (p<0.01). The level of osteocalcin, a bone formation marker, was higher in OVX-Ca rats than in controls 4 weeks (610.08±10.41 vs. 551.61±12.34 ng/mL) and 8 weeks (552.05±19.67 vs. 502.98±22.76 ng/mL) after fusion surgery (p<0.05). The level of C-terminal telopeptide fragment of type I collagen, a bone resorption marker, was significantly lower in OVX-Ca rats than in controls 4 weeks (77.07±12.57 vs. 101.75±7.20 ng/mL) and 8 weeks (69.58±2.45 vs. 77.15±4.10 ng/mL) after fusion surgery (p<0.05). A mechanical strength test showed that the L4-5 vertebrae in the OVX-Ca group withstood a 50% higher maximal load compared with the controls (p<0.01). CONCLUSION: Dietary calcium given to OVX rats after lumbar fusion surgery improved fusion volume and mechanical strength in an ovariectomized rat model.

11.
Acta Neurochir (Wien) ; 154(12): 2215-23, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23053289

RESUMEN

BACKGROUND: The purpose of this study was to evaluate the therapeutic effects of combination therapy with curcumin and alendronate on bone remodeling after ovariectomy in rats. METHODS: Eighty female Sprague-Dawley rats underwent either a sham operation (the sham group) or bilateral ovariectomy (OVX). The ovariectomized animals were randomly distributed amongst four groups: untreated OVX group, curcumin-administered group, alendronate-administered group, and the combination therapy group. At 8 and 12 weeks after surgery, rats from each of the groups were euthanized. Serum biochemical markers of bone turnover, including osteocalcin and alkaline phosphatase (ALP), and the telopeptide fragment of type I collagen C-terminus (CTX) were analyzed. Bone histomorphometric parameters of the 4th lumbar vertebrae were determined by micro-computed tomography (CT). In addition, mechanical strength was determined by a three-point bending test. RESULTS: Serum biochemical markers of bone turnover in the experiment groups (curcumin administered group, alendronate administered group, and the combination therapy group) were significantly lower than in the untreated OVX group (p < 0.05). The combination therapy group had lower ALP and CTX-1 concentrations at 12 weeks, which were statistically significant compared with the curcumin only and the alendronate only group (p < 0.05). The combination therapy group had a significant increase in BMD at 8 weeks and Cr.BMD at 12 weeks compared with the curcumin-only group (p = 0.005 and p = 0.013, respectively). The three point bending test showed that the 4th lumbar vertebrae of the combination therapy group had a significantly greater maximal load value compared to that of the curcumin only and the alendronate only group (p < 0.05). CONCLUSIONS: The present study demonstrated that combination therapy with a high dose of curcumin and a standard dose of alendronate has therapeutic advantages over curcumin or alendronate monotherapy, in terms of the synergistic antiresorptive effect on bone remodeling, and improving bone mechanical strength.


Asunto(s)
Alendronato/uso terapéutico , Remodelación Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Curcumina/uso terapéutico , Vértebras Lumbares/efectos de los fármacos , Osteoporosis/tratamiento farmacológico , Fosfatasa Alcalina/sangre , Animales , Densidad Ósea/efectos de los fármacos , Colágeno Tipo I/sangre , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Osteocalcina/sangre , Ovariectomía , Ratas , Ratas Sprague-Dawley
12.
ACS Nano ; 4(4): 2249-55, 2010 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-20384322

RESUMEN

A facile, cost-effective, and manufacturable method to produce gold-polymer nanocomposite plasmonic nanorod arrays in high-aspect-ratio nanoporous alumina templates is reported, where the formation of gold nanoparticles and the polymerization of a photosensitive polymer by ultraviolet light are simultaneously performed. Transverse mode coupling within a two-dimensional array of the nanocomposite rods results in a progression of resonant modes in the visible and infrared spectral regions when illuminated at normal incidence, a phenomenon previously observed in nanoarrays of solid gold rods in an alumina template. Finite element full-wave analysis in a three-dimensional computational domain confirms our hypothesis that nanoparticles, arranged in a columnar structure, will show a response similar to that of solid gold rods. These studies demonstrate a new simple method of plasmonic nanoarray fabrication, apparently obviating the need for a cumbersome electrochemical process to grow nanoarrays.


Asunto(s)
Óxido de Aluminio/química , Oro/química , Nanocompuestos/química , Nanotecnología/instrumentación , Polímeros/química , Microscopía Electrónica de Rastreo , Fenómenos Ópticos , Porosidad , Análisis Espectral
13.
J Nat Med ; 63(3): 274-82, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19343477

RESUMEN

Magnolol, honokiol, and obovatol are well-known bioactive constituents of the bark of Magnolia officinalis and have been used as traditional Chinese medicines for the treatment of neurosis, anxiety, and stroke. We recently isolated novel active compound (named 4-O-methylhonokiol) from the ethanol extract of Magnolia officinalis. The present study aimed to test two different doses of ethanol extracts of Magnolia officinalis (5 and 10 mg/kg/mouse, p.o., 1 week) and 4-O-methylhonokiol (0.75 and 1.5 mg/kg/mouse, p.o., 1 week) administered for 7 days on memory impairment induced by scopolamine (1 mg/kg body weight i.p.) in mice. Memory and learning were evaluated using the Morris water maze and the step-down avoidance test. Both the ethanol extract of Magnolia officinalis and 4-O-methylhonokiol prevented memory impairment induced by scopolamine in a dose-dependent manner. The ethanol extract of Magnolia officinalis and 4-O-methylhonokiol also dose-dependently attenuated the scopolamine-induced increase of acetylcholinesterase (AChE) activity in the cortex and hippocampus of mice, and inhibited AChE activity in vitro with IC(50) (12 nM). This study, therefore, suggests that the ethanol extract of Magnolia officinalis and its major ingredient, 4-O-methylhonokiol, may be useful for the prevention of the development or progression of AD.


Asunto(s)
Compuestos de Bifenilo/farmacología , Etanol/química , Lignanos/farmacología , Magnolia/química , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Acetilcolinesterasa/metabolismo , Animales , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/enzimología , Activación Enzimática/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/enzimología , Masculino , Ratones , Ratones Endogámicos ICR , Estructura Molecular
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