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1.
Eur J Neurol ; 24(9): 1166-1172, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28744942

RESUMEN

BACKGROUND AND PURPOSE: Large-scale studies of utilization of medical services among patients with Alzheimer's disease (AD) are lacking. We aimed to investigate the usage of Western medicine and traditional Chinese medicine (TCM) among these patients in Taiwan. METHODS: We analyzed one million samples from the National Health Insurance Research Database in Taiwan. Patients (n = 1814) newly diagnosed with AD in 2001-2010 were divided into TCM users (n = 528) and non-TCM users (n = 1286). RESULTS: Compared with non-TCM users, TCM users were younger, had a higher female:male ratio and higher utilization rate of Western medicine. The median interval between diagnosis and the first TCM consultation was 7.92 months. Donepezil and rivastigmine were commonly prescribed medications. Chinese herbal medicine was the most popular treatment among TCM users. CONCLUSIONS: This study revealed the specific usage patterns of TCM and non-TCM medical services among patients with AD. The information could be used for improving the healthcare of patients with AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/epidemiología , Medicina Tradicional China/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Inhibidores de la Colinesterasa/uso terapéutico , Donepezilo , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Humanos , Indanos/uso terapéutico , Masculino , Persona de Mediana Edad , Piperidinas/uso terapéutico , Rivastigmina/uso terapéutico , Factores Sexuales , Taiwán/epidemiología , Tiempo de Tratamiento , Urbanización
2.
Allergy ; 71(11): 1626-1631, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27286483

RESUMEN

BACKGROUND: An individual's birth month has been associated with allergic diseases, but little is known about the association between birth month and atopic dermatitis (AD). OBJECTIVE: The aim of this study was to investigate the risk of AD in children born in various months. METHODS: Using Taiwan's National Health Insurance Research Database, we conducted a case-control study that included 31 237 AD cases and 124 948 age- and gender-matched controls without AD. Data regarding sociodemographic factors and coexisting medical conditions were collected and controlled in the multivariate logistic regression to determine the adjusted odds ratios and 95% confidence intervals for AD associated with the participant's birth month. RESULTS: Compared with people born in May, people born in December had the highest risk of AD (OR 1.17, 95% CI 1.10-1.25), followed by people born in October (OR 1.15, 95% CI 1.08-1.22) and November (OR 1.13, 95% CI 1.06-1.20). Low income (OR 1.28), asthma (OR 1.88), allergic rhinitis (OR 1.70), psoriasis (OR 2.36), vitiligo (OR 1.99), urticaria (OR 2.14), and systemic lupus erythematosus (OR 1.91) were significant coexisting medical conditions associated with AD. CONCLUSION: Being born in December, October, or November may be associated with an increased risk of AD. Future investigations are needed to evaluate the possible mechanism behind the association between birth month and AD.


Asunto(s)
Dermatitis Atópica/epidemiología , Dermatitis Atópica/etiología , Parto , Vigilancia de la Población , Estaciones del Año , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Oportunidad Relativa , Prevalencia , Factores Socioeconómicos , Taiwán/epidemiología , Adulto Joven
3.
J Phys Condens Matter ; 33(23)2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-33784652

RESUMEN

Cr5Te8is a half metal with 2D van der Waals ferromagnetic structure and its magnetic properties can be tuned by changing the proportionality of Cr and Te. We report an investigation of magnetization and magnetic anisotropy near the critical transition region of a Cr5-yTe8single crystal with the static and dynamic probes, to unravel the nature of field-dependent spin-spin interactions. The magnetic transition temperatureTCincreasing from 255 K (at near zero-field) to 279 K (at 65 kOe along theab-plane) has been identified. Accordingly, a phase diagram of field versus transition temperature has been established. From the analysis of the field dependence of the critical behavior, we provided evidence that the scenario of 2D Heisenberg-type interactions can be employed to interpret the field-dependent magnetic transitions in Te-rich Cr4.8Te8. The precise picture for the field-reduced spin-spin interaction range has been obtained. The conclusion drawn from the present study demonstrated that Cr4.8Te8is a promising candidate for the spintronic applications with a tunable magnetic transition temperature.

4.
Nanotechnology ; 20(31): 315702, 2009 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-19597259

RESUMEN

A series of anatase phase Fe-doped TiO2 nanoparticles are prepared by a modified sol-gel method. Spontaneous Raman spectroscopy is utilized to characterize the crystal structures of these nanoparticles and investigate their structural transformation under the exposure of a 532 nm green laser. The anatase phase of TiO2 can be effectively converted into the rutile phase with the assistance of Fe doping. It is found that the critical laser intensity for phase transformation decreases with increasing the Fe content. We ascribe this tendency to the enhanced optical absorption and the photo-induced thermal heating effect, which can be associated with the defect structure within the bandgap of Fe- TiO2 nanoparticles. Our study demonstrates an all-optical approach to pump and probe the phase transformation of metal-doped TiO2 nanoparticles.

6.
Sci Rep ; 9(1): 7828, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-31127125

RESUMEN

The potential applications of perovskite manganite R1-xAxMnO3 (R = rare earth element; A = Sr, Ca) thin films have been continuously explored due to their multi-functional properties. In particular, the optimally hole-doped La0.67Ca0.33MnO3 thin film demonstrates a colossal magneto-resistance that is beneficial to the performance of spintronic devices. To understand the effect of R and A ions on the material properties, we systematically measure the resistivity, magnetization, and electronic energy states for three optimally hole-doped R0.67A0.33MnO3 thin films with R = La, Sm and A = Sr, Ca. Various energy parameters are derived based on the X-ray absorption and X-ray photoelectron spectra, including the band gap, the charge frustration energy and the magnetic exchange energy. It is interesting to find that the replacement of La with Sm is more effective than that of Sr with Ca in terms of tuning the electrical property, the Curie temperature, and the band gap. The strain-induced reduction of the O 2p- Mn 3d hybridization and the interplay of R/A site disorder and strain effect are discussed. The results of this study provide useful information for the band design of perovskite oxide films.

7.
QJM ; 112(6): 437-442, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30778546

RESUMEN

BACKGROUND: The effect of traditional Chinese medicine (TCM) on the outcomes of dementia remains unclear. Our purpose is to compare the use of emergency care and hospitalization in patients with post-stroke cognitive impairment (PSCI) with or without treatment of TCM. METHODS: In a stroke cohort of 67 521 patients with PSCI aged over 40 years obtained from the 23 million people in Taiwan's national health insurance between 2000 and 2007, we identified 6661 newly diagnosed PSCI patients who were treated with TCM and 6661 propensity score-matched PSCI patients who were not treated with TCM. Under the control of immortal time bias, we calculated the adjusted rate ratios (RRs) and 95% CIs of the 1-year use of emergency care and hospitalization associated with TCM. RESULTS: The means of the emergency care medical visits (0.40 ± 0.98 vs. 0.47 ± 1.01, P = 0.0001) and hospitalization (0.72 ± 1.29 vs. 0.96 ± 1.49, P < 0.0001) were lower in the PSCI patients treated with TCM than in those without the TCM treatment. The RRs of emergency care and hospitalization associated with TCM were 0.87 (95% CI = 0.82-0.92) and 0.81 (95% CI = 0.78-0.84), respectively. The PSCI patients treated with a combination of acupuncture and herbal medicine had the lowest risk of emergency care visits and hospitalization. CONCLUSIONS: Our study raises the possibility that TCM use was associated with reduced use of emergency care and hospitalization after PSCI. However, further randomized clinical trials are needed to provide solid evidence of this benefit and identify the underlying mechanism.


Asunto(s)
Disfunción Cognitiva/terapia , Servicios Médicos de Urgencia/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Medicina Tradicional China , Accidente Cerebrovascular/terapia , Terapia por Acupuntura , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Medicamentos Herbarios Chinos , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Accidente Cerebrovascular/complicaciones , Taiwán
8.
Sci Rep ; 9(1): 5160, 2019 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-30914713

RESUMEN

This study probes the temperature-dependent strain that is strongly correlated with the orbital and magnetic structures of epitaxial films of Nd0.35Sr0.65MnO3 (NSMO) that are fabricated by pulsed laser deposition with two thicknesses, 17 (NS17) and 103 nm (NS103) on SrTiO3 (STO) substrate. This investigation is probed using X-ray diffraction (XRD) and absorption-based techniques, X-ray linear dichroism (XLD) and the X-ray magnetic circular dichroism (XMCD). XRD indicates a significant shift in the (004) peak position that is associated with larger strain in NS17 relative to that of NS103 at both 30 and 300 K. Experimental and atomic multiplet simulated temperature-dependent Mn L3,2-edge XLD results reveal that the stronger strain in a thinner NS17 film causes less splitting of Mn 3d eg state at low temperature, indicating an enhancement of orbital fluctuations in the band above the Fermi level. This greater Mn 3d orbital fluctuation can be the cause of both the enhanced ferromagnetism (FM) as a result of spin moments and the reduced Néel temperature of C-type antiferromagnetism (AFM) in NS17, leading to the FM coupling of the canted-antiferromagnetism (FM-cAFM) state in NSMO/STO epitaxial films at low temperature (T = 30 K). These findings are also confirmed by Mn L3,2-edge XMCD measurements.

9.
Acta Biomater ; 4(5): 1530-5, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18485846

RESUMEN

Current orthopaedic biomaterials research mainly focuses on designing implants that could induce controlled, guided and rapid healing. In the present study, the surface morphologies of titanium (Ti) and niobium (Nb) metals were tailored to form nanoporous, nanoplate and nanofibre-like structures through adjustment of the temperature in the alkali-heat treatment. The in vitro bioactivity of these structures was then evaluated by soaking the treated samples in simulated body fluid (SBF). It was found that the morphology of the modified surface significantly influenced the apatite-inducing ability. The Ti surface with a nanofibre-like structure showed better apatite-inducing ability than the nanoporous or nanoplate surface structures. A thick dense apatite layer formed on the Ti surface with nanofibre-like structure after 1 week of soaking in SBF. It is expected that the nanofibre-like surface could achieve good apatite formation in vivo and subsequently enhance osteoblast cell adhesion and bone formation.


Asunto(s)
Apatitas/química , Materiales Biocompatibles/química , Líquidos Corporales/química , Niobio/química , Titanio/química , Ensayo de Materiales , Metales/química , Propiedades de Superficie
10.
Sci Rep ; 8(1): 9496, 2018 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-29934506

RESUMEN

In this study, an in situ ß-Ti-Nb composites reinforced with TiC particles with an ultrafine grain size were fabricated using a powder metallurgical (PM) method. The microstructures and mechanical properties of the composites were characterized using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and compression tests. TiC particles were formed in the ball-milled powders after annealing at 600 °C due to a chemical reaction between stearic acid and titanium. Using high-pressure sintering (HPS) on an apparatus with six tungsten carbide anvils, a fully dense ß-Ti-Nb composite reinforced with fine in situ TiC particles was obtained. The TiC particles exhibit particle sizes of ~500 nm, uniformly distributed in the composite matrix, which had grain sizes of ~600 nm. Thus, the TiC-ß-Ti-Nb composite show very high compression yield strength and relatively high plasticity contributed by grain refinement and TiC particles strengthening. The composite with 45 vol.% TiC exhibited excellent mechanical properties, with a yield compressive strength of 1990 MPa and plastic strain of 9.12%. More over, a modified rule-of-mixture (ROM) was presented to describe the combined strengthening effect of grain refinement and TiC particles.

11.
Sci Rep ; 7(1): 6612, 2017 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-28747739

RESUMEN

Ferromagnetic resonance driven spin pumping (FMR-SP) is a novel method to transfer spin current from the ferromagnetic (FM) layer into the adjacent normal metal (NM) layer in an FM/NM bilayer system. Consequently, the spin current could be probed in NM layer via inverse spin Hall effect (ISHE). In spite of numerous ISHE studies on FM/Pt bilayers, La0.7Sr0.3MnO3(LSMO)/Pt system has been less explored and its relevant information about interface property (characterized by spin mixing conductance) and spin-charge conversion efficiency (characterized by spin Hall angle) is a matter of importance for the possible applications of spintronic devices. In this work, the technique of FMR-SP has been applied on two series of LSMO/Pt bilayers with the thickness of each layer being varied. The thickness dependences of ISHE voltage allow to extract the values of spin mixing conductance and spin Hall angle of LSMO/Pt bilayers, which are (1.8 ± 0.4) × 1019 m-2 and (1.2 ± 0.1) % respectively. In comparison with other FM/Pt systems, LSMO/Pt has comparable spin current density and spin mixing conductance, regardless its distinct electronic structure from other ferromagnetic metals.

12.
Dalton Trans ; 46(4): 1228-1236, 2017 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-28058412

RESUMEN

Three new metal chalcogenides have been identified in MnN-1(Gd2-xInx)SN+2 with N = 3, 4, and 5 via a flux-growth synthesis. All compounds crystallize in the same space group of orthorhombic Cmcm with cell constants: Mn2GdInS5 (1), a = 3.789(1) Å, b = 12.411(1) Å, and c = 15.489(1) Å; Mn3Gd2S6 (2), a = 3.778(1) Å, b = 12.505(2) Å, and c = 19.114(2) Å; Mn4Gd2S7 (3), a = 3.769(1) Å, b = 12.466(2) Å, and c = 22.289(3) Å. Compounds 1-3 form a homologous series through the modulation of the MnS unit, whose structures represent a complete system of the corresponding lillianites (N1,N2L) of 3,3L, 4,4L and 5,5L. The gradually wider slabs formed in the series result in a monotonic increase along the c dimensions from 1 to 3. Crystal 3 is the first to achieve a predicted structure of 5,5L. Mn2GdInS5 (1) displays a weak antiferromagnetic (AFM) ordering at 10 K and the Weiss constant (θ) of -0.76 K. Mn2Gd1.5In0.5S5 (1a), an isostructure of 1, shifts the AFM transition temperature to 12 K and possesses a slightly larger θ constant of -6.06 K. Mn4Gd2S7 (3), featuring the thickest slabs in this series, shows a significant antiferromagnetic behavior beginning at a high temperature of 70 K and has a largest θ constant of -40.25 K. A small amount of impurity α-Gd2S3 with an AFM transition temperature around 4 K was characterized in sample 3, which does not interfere with the magnetic ordering of 3 at much higher temperatures. These magnetic chalcogenides display band gaps of 1.66 eV for 1, 1.75 eV for 1a, and 1.44 eV for 3.

13.
Cancer Res ; 53(12): 2865-73, 1993 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-8504428

RESUMEN

To investigate the effect of DNA replication on the mutation spectrum induced in diploid human fibroblasts by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), cells were synchronized and exposed to MNNG either at the G1-S border or in late S phase, and the mutations in the hypoxanthine (guanine) phosphoribosyltransferase (hprt) gene were examined. The coding regions of 92 independent mutants were characterized by direct sequencing of mRNA-polymerase chain reaction-amplified complementary DNA. While there was little difference in the sensitivity of the two populations to the cytotoxic effects of MNNG, the frequency of mutants induced in late S populations was significantly lower than that induced in G1-S populations. The majority of induced complementary DNA mutations were single base substitutions (54%) and splice site mutations (43%). Analysis of the intron-exon boundaries of more than one-half of the splicing mutants showed that almost all contained base substitutions in the hprt gene. A broad mutational spectrum was observed in low-dose (4, 6, or 8 microM) treatments; only 27% were G to A transitions, whereas 80% of base substitutions derived from the high-dose (10 or 12 microM) treatments were G to A transitions in G1-S populations. An intermediate frequency (64%) of G to A transitions was observed in late S populations exposed to MNNG. When the causative premutation lesion was O6-methylguanine, 75% of G to A transitions that were observed in G1-S populations clustered on both the transcribed and the nontranscribed strands of the 5' half of the hprt gene. In contrast, 50% of G to A transitions were located only on the nontranscribed strand of this region in late S populations. The results indicate that O(6)-alkylguanine-DNA-alkyltransferase may not efficiently remove O(6)-methylguanine from the 5' half of the gene but can repair lesions far away from this region during initiation of replication. Our results are consistent with the notion that the putative origin of replication is located at intron 1 of the hprt gene.


Asunto(s)
Replicación del ADN/genética , ADN/efectos de los fármacos , Fase G1/efectos de los fármacos , Hipoxantina Fosforribosiltransferasa/genética , Metilnitronitrosoguanidina/toxicidad , Mutación/genética , Fase S/efectos de los fármacos , Secuencia de Aminoácidos/efectos de los fármacos , Afidicolina/farmacología , Secuencia de Bases/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Diploidia , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fase G1/genética , Guanina/análogos & derivados , Guanina/metabolismo , Humanos , Metiltransferasas/metabolismo , Datos de Secuencia Molecular , O(6)-Metilguanina-ADN Metiltransferasa , Reacción en Cadena de la Polimerasa/métodos , Fase S/genética , Análisis de Secuencia de ADN , Factores de Tiempo
14.
Sci Rep ; 5: 12780, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26239479

RESUMEN

Modulation of the superconducting state possessing a C-type antiferromagnetic phase in the Nd0.35Sr0.65MnO3/YBa2Cu3O7 heterostructure is investigated, with the Nd0.35Sr0.65MnO3 thickness (t) varying from 40 to 200 nm. Both the superconducting transition temperature and the upper critical field along the c-axis decrease with increasing t; while the in-plane coherence length increases from 2.0 up to 3.6 nm. Meanwhile, the critical current density exhibits a field-independent behavior, indicating an enhanced flux pinning effect. Furthermore, low-temperature spin canting induces a breakdown and re-entrance of the superconductivity, demonstrating a dynamic completion between the superconducting pairing and the exchange field. An unexpected colossal magnetoresistance is observed below the superconducting re-entrance temperature at t = 200 nm, which is attributed to the dominant influence of the exchange field over the pairing energy.

15.
J Gerontol A Biol Sci Med Sci ; 54(8): M389-94, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10496543

RESUMEN

BACKGROUND: Elderly people often suffer from disturbed sleep. Because traditional Chinese medicine indicates that acupressure therapy may induce sedation, testing the effectiveness of acupressure in enhancing the quality of sleep of institutionalized residents with a well-designed scientific study is needed. METHODS: A randomized block experimental design was used. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was used as a screening tool to select subjects with sleep disturbance. By matching the effects of hypertension, hypnosis, naps, and exercise, subjects were randomly assigned to an acupressure group, a sham acupressure group, and a control group. Each group had 28 subjects for a total of 84 subjects. The same massage routine was used in the acupressure group and the sham acupressure group, whereas only conversation was employed in the control group. RESULTS: There were significant differences in PSQI subscale scores of the quality, latency, duration, efficiency, disturbances of sleep, and global PSQI scores among subjects in the three groups before and after interventions. Furthermore, there was a significant reduction in the frequencies of nocturnal awakening and night wakeful time in the acupressure group compared to the other two groups. CONCLUSIONS: This study confirmed the effectiveness of acupressure in improving the quality of sleep of elderly people and offered a nonpharmacological therapy method for sleep-disturbed elderly people.


Asunto(s)
Acupresión , Trastornos del Sueño-Vigilia/terapia , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Distribución de Chi-Cuadrado , Femenino , Humanos , Institucionalización , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Resultado del Tratamiento
16.
Life Sci ; 65(20): 2071-82, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10579461

RESUMEN

Uncaria rhynchophylla (Miq.) Jack (UR) and Gastrodia elata BI. (GE) are traditional Chinese herbs that are usually used in combination to treat convulsive disorders, such as epilepsy, in China. The aim of this study was to compare the anticonvulsive and free radical scavenging activities of UR alone and UR in combination with GE in rats. For the in vitro studies, brain tissues from 6 male Sprague-Dawley (SD) rats were treated with 120 microg/ml kainic acid (KA), with or without varied concentrations of UR or UR plus GE. For the in vivo studies, male SD rats (6 per group) received intraperitoneal (i.p.) injection of KA 12 mg/kg to induce epileptic seizures and generation of free radicals, with or without oral administration of UR 1 g/kg alone or UR 1 g/kg plus GE 1 g/kg. Epileptic seizures were verified by behavioral observations, and electroencephalography (EEG) and electromyography (EMG) recordings. These results showed that UR alone decreased KA-induced lipid peroxide levels in vitro, whereas UR plus GE did not produce a greater effect than UR alone. UR significantly reduced counts of wet dog shakes (WDS), paw tremor (PT) and facial myoclonia (FM) in KA-treated rats and significantly delayed the onset time of WDS, from 27 min in the control group to 40 min in the UR group. UR plus GE did not inhibit seizures more effectively than UR alone, but did further prolong the onset time of WDS to 63 min (P < 0.05 vs. UR alone). UR alone reduced the levels of free radicals in vivo, as measured by lipid peroxidation in the brain and luminol-chemiluminescence (CL) counts and lucigenin-CL counts in the peripheral whole blood, but the combination of GE and UR did not reduce free radical levels more markedly than UR alone. In conclusion, our results indicate that UR has anticonvulsive and free radical scavenging activities, and UR combined with GE exhibit greater inhibition on the onset time of WDS than UR alone. These findings suggest that the anticonvulsive effects of UR and GE may be synergistic. However, the mechanism of interaction between UR and GE remains unknown.


Asunto(s)
Anticonvulsivantes/farmacología , Encéfalo/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Epilepsia/prevención & control , Depuradores de Radicales Libres/farmacología , Peroxidación de Lípido/efectos de los fármacos , Plantas Medicinales , Animales , Conducta Animal/efectos de los fármacos , Encéfalo/metabolismo , Combinación de Medicamentos , Sinergismo Farmacológico , Electroencefalografía , Electromiografía , Epilepsia/inducido químicamente , Radicales Libres , Ácido Kaínico/toxicidad , Peróxidos Lipídicos/metabolismo , Masculino , Medicina Tradicional China , Ratas , Ratas Sprague-Dawley
17.
Life Sci ; 67(10): 1185-95, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10954052

RESUMEN

Vanillyl alcohol (VA) is a component of Gastrodia elata Bl. (GE), which is a traditional Chinese herb widely used to treat convulsive disorders or dizziness. This study examined the role of VA in the anticonvulsive properties of GE in a Sprague-Dawley rat model of epilepsy. The anticonvulsive and free radical scavenging activities of VA were examined after intracortical injection of ferric chloride (100 mM, 8 microl) to induce epileptic seizures. These seizures were verified by behavioral observations and electroencephalographic (EEG) and electromyographic (EMG) recordings. Ferric chloride injection resulted in increased lipid peroxide levels in the ipsilateral and contralateral cerebral cortex, and increased luminol-chemiluminescence (CL) and lucigenin-CL counts in the peripheral blood. Intraperitoneal injection (i.p.) of VA (200 mg/kg or 100 mg/kg) or phenytoin 10 mg/kg prior to ferric chloride administration significantly inhibited wet dog shakes (WDS) and lipid peroxide levels in the bilateral cerebral cortex. VA 200 mg/kg also significantly reduced luminol-CL and lucigenin-CL counts in the peripheral blood, but no significant effect was observed following administration of VA 100 mg/kg or phenytoin. These data indicate that VA has both anticonvulsive and suppressive effects on seizures and lipid peroxidation induced by ferric chloride in rats. Data from the present study also demonstrate that VA has free radical scavenging activities, which may be responsible for its anticonvulsive propertics. This finding is consistent with the results from previous studies that generation of superoxide radical evoked by injection of iron salt into rat brain plays a critical role in ferric chloride-induced seizures. In addition, the results of the present study suggest that the anticonvulsive effect of GE may be attributable, at least in part, to its VA component.


Asunto(s)
Anticonvulsivantes/farmacología , Alcoholes Bencílicos/farmacología , Epilepsia/tratamiento farmacológico , Depuradores de Radicales Libres/farmacología , Acridinas , Animales , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cloruros , Convulsivantes/antagonistas & inhibidores , Convulsivantes/toxicidad , Medicamentos Herbarios Chinos/farmacología , Electroencefalografía , Electromiografía , Epilepsia/sangre , Epilepsia/inducido químicamente , Compuestos Férricos/antagonistas & inhibidores , Compuestos Férricos/toxicidad , Peroxidación de Lípido/efectos de los fármacos , Peróxidos Lipídicos/sangre , Peróxidos Lipídicos/metabolismo , Mediciones Luminiscentes , Luminol , Masculino , Plantas Medicinales , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo
18.
Life Sci ; 69(13): 1485-96, 2001 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-11554610

RESUMEN

Bu-Zhong-Yi-Qi-Tang (BZYQT), a Chinese herbal medicine, inhibited the proliferation of human hepatoma cell lines (Hep3B, HepG2 and HA22T) dose-dependently. The IC50s of BZYQT on the proliferation of Hep3B, HepG2 and HA22T were 432.5+/-31.8 microg/ml, 455.4+/-24.2 microg/ml, and 2284.3+/-77.2 microg/ml respectively on day 3. However, BZYQT did not significantly inhibit the proliferation of normal human hepatocytes (Chang liver, CCL-13) at the concentration under 5,000 microg/ml. Major compounds of BZYQT, including astragaloside IV, ginsenoside Rb1 and Rg1, saikosaponin a and c, and glycyrrhizin, have been identified. To investigate the key inhibitors of BZYQT. Hep3B cells were treated with BZYQT, individual major compounds of BZYQT, and mixture of major compounds in the same ratio as present in BZYQT. Significant inhibition of proliferation was detected in BZYQT and its major compounds mixture in a comparable level. Not any individual major compound examined could suppress the proliferation of Hep3B cells. This data indicated that there could be synergistic or additive effects of the ingredients in BZYQT. BrdU incorporation, cell cycle analysis and DNA fragmentation assay revealed that BZYQT suppressed the proliferation of hepatoma cells via G0/G1 cell cycle arrest and inhibition of DNA synthesis followed by apoptosis.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Animales , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Medios de Cultivo , Fragmentación del ADN/efectos de los fármacos , ADN de Neoplasias/metabolismo , Electroforesis en Gel de Poliacrilamida , Humanos , Neoplasias Hepáticas Experimentales/patología , Ratas , Células Tumorales Cultivadas
19.
J Chromatogr A ; 840(1): 71-9, 1999 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-10335612

RESUMEN

When the sewage sludge containing the persistent, lipophilic, metabolite 4-nonylphenol (4-NP) has been disposed of in the environment it's toxic nature can lead to serious health risks to human beings and can also affect plants and aquatic organisms. Supercritical fluid extraction (SFE) is a new and powerful technique for extracting the organic contaminants from the solid phase. The present study was conducted to investigate optimal conditions for the quantitative extraction of 4-NP by SFE and to determine the concentration of 4-NP in municipal sewage sludge. The effect of several parameters such as temperature, pressure, static extraction time, dynamic extraction time, CO2 flow-rate, sample mass and modifier on the extraction were investigated. The optimal conditions for the extraction of the spiked sample were fluid pressure 97 bar, temperature 40 degrees C, flow-rate 3.0 ml/min, static extraction time 2 min, dynamic extraction time 5 min and modifier methanol (0.5 ml). Extracts were analyzed by gas chromatography-mass spectrometry. Concentration of 4-NP in the anaerobically degraded sludge of the De-Haw Sewage Treatment Plant in Taiwan was found to be 243.9 mg/kg. The extraction efficiency of the SFE method was compared with the conventional Soxhlet extraction method. The overall recovery of the SFE method was found to be greater and the results indicate that SFE is an efficient method for extracting 4-NP from sewage sludge.


Asunto(s)
Técnicas de Química Analítica/métodos , Fenoles/análisis , Aguas del Alcantarillado/química , Dióxido de Carbono , Cromatografía de Gases , Contaminación Ambiental/prevención & control , Espectrometría de Masas , Metanol/farmacología , Presión , Temperatura , Factores de Tiempo , Agua
20.
Anticancer Res ; 17(3C): 2095-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9216670

RESUMEN

Norcantharidin[3], the demethylated product of cantharidin[1] has been used for the treatment of hepatoma, carcinomas of esophagus and gastric cardia, leukopenia and hepatitis. Since the enzyme xanthine oxidase is involved in the diseases mentioned above, and the reactive oxygen species produced by the enzyme induces DNA damage and oxidative damage of tissues, fourteen cantharidin analogues and cantharidimide derivatives were tested for their effects on xanthine oxidase. The results showed that these compounds, listed in Figure 1, displayed very weak inhibitory effects on xanthine oxidase. Contrary to expectation, disodium cantharidate [2], Norcantharidin [3], dehydronorcantharidin [4], disodium dehydronorcantharidate [5], N-(2-pyridyl) cantharidimide [12], N-(3pyridyl) cantharidimide [13] and N-(4-pyridyl) cantharidimide [14] showed a slight stimulating effect on xanthine oxidase at several concentrations.


Asunto(s)
Cantaridina/análogos & derivados , Cantaridina/farmacología , Inhibidores Enzimáticos/farmacología , Xantina Oxidasa/antagonistas & inhibidores , Alopurinol/farmacología , Antineoplásicos/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Cantaridina/química , Cinética , Estructura Molecular , Relación Estructura-Actividad
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