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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(9): 772-777, 2020 Sep 12.
Artículo en Chino | MEDLINE | ID: mdl-32894911

RESUMEN

Objective: To explore the therapeutic effect of carnosine and dexamethasone in lung injury caused by seawater drowning. Methods: The in vitro experiments with A549 cells were divided into 5 groups: blank control group (C), seawater injury group (S), seawater injury+dexamethasone treatment group (S+D), seawater injury+carnosine treatment group (S+C), seawater injury dexamethasone and carnosine combined therapy(S+D+C) group. The optimal therapeutic dose of drugs for the treatment of seawater drowning lung injury was tested in vitro. Based on the optimal dose, the levels of TNF-α and IL-6 in each group at different time points were detected at the cell level by ELISA. The level of apoptosis was detected by flow cytometry. The in vivo experiments with SD rats were randomly divided into 5 groups (n=8 each): blank control group (RC),seawater drowning injury group (RS),seawater drowning injury+dexamethasone treatment group (RSD),seawater drowning injury+carnosine treatment group (RSC),seawater drowning injury+dexamethasone+carnosine combined treatment group (RSDC). The animal model with seawater inhalation acute lung injury was made by intratracheal infusion (4 ml/kg). The pathological changes of the lungs were observed. The expression of superoxide dismutase (SOD) in each group was detected by Western blot. Results: The results of in vitro experiments showed significant increase of apoptosis after seawater injury. The normal cell rate in group C was 98.3% while the apoptosis rate was 1.7%. The normal cell in group S was 18.8%, and the apoptosis rate was 81% (P<0.01). TNF-α and IL-6 levels in group S increased to 180.25 ng/L and 61.56 ng/L, respectively, which were statistically significant compared with group C (P<0.01). After drug protection, apoptosis was reduced in S+D group, S+C group and S+D+C group, with apoptosis rates of 65.4%, 70.9% and 42.6%, respectively. The contents of TNF-α and IL-6 also decreased in the S+D+C group (P<0.01). The results of in vivo experiments showed obvious lung injury and disordered lung tissue structures in the RS group at 4 h after modeling. There was hemorrhage in the pulmonary interstitium and a large number of inflammatory cells. Results of western blot showed that the expression of SOD increased in the RS group. Compared with RS group, the treatment alleviated acute lung injury and decreased the expression level of SOD in RSD, RSC and RSDC groups (P<0.01). Conclusion: Dexamethasone and carnosine reduced the influence of seawater inhalation on the lung in the rat model. The positive effect of combination of these two drugs on lung injury caused by seawater inhalation was stronger than a single drug.


Asunto(s)
Ahogamiento , Lesión Pulmonar , Animales , Carnosina , Dexametasona , Pulmón , Ratas , Ratas Sprague-Dawley , Agua de Mar , Factor de Necrosis Tumoral alfa
2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 47(11): 907-912, 2019 Nov 24.
Artículo en Chino | MEDLINE | ID: mdl-31744281

RESUMEN

Objective: To explore the clinical characteristics and related factors of somatization symptoms in outpatients with psychiatric disorders of the cardiology department in general hospital. Methods: Cross-sectional survey method was used in this study. From August 2017 to September 2018, 508 outpatients of our department with suspected mental disorders, who complained of physical discomfort and screened by the "Three Questions" method recommended by the Chinese Expert Consensus on Psychological Prescriptions of Cardiovascular Patients in 2014, were consecutively included. General Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire (PHQ-9), Patient Health Questionnaire-15 (PHQ-15) and self-made general demographic questionnaire (including age, sex, marital status, educational level, occupation, duration of disease, clinical diagnosis and the process of medical treatment for the main somatic symptoms in recent one year) were used to investigate these patients, under the assistance of unified training psychological consultants. The detection rate of anxiety and depression, the degree and distribution of somatization symptoms in outpatients with mental disorders were analyzed, and the related factors affecting the occurrence of somatization symptoms were screened by multivariate logistic regression. Results: The selected patients were (51.3±10.1) years old, of which 37.8% (192/508) were males and 62.2% (316/508) were females. The total detection rate of anxiety/depression was 86.8% (441/508), and the detection rate of somatization symptoms was 93.1% (473/508). The number of positive symptom items in PHQ-15 was 8.0±2.7, and the detection rate of anxiety/depression was 78.6% (372/473) in patients with somatization symptoms. There were significant differences in the proportion of women, the average number of outpatient visits and hospitalizations in the past one year, GAD-7 score and PHQ-9 score among the patients with mild, moderate and severe somatization symptoms (all P<0.05). PHQ-15 score was positively correlated with GAD-7 score (r=0.524 5, P<0.001) and PHQ-9 score (r=0.574 9, P<0.001) in patients with somatization symptoms. Stepwise logistic regression analysis showed that total scores of PHQ-9 (OR=8.020, 95%CI 3.470-18.930, P<0.001) and GAD-7 (OR=6.526, 95%CI 2.903-13.045, P<0.001) and female (OR=4.440, 95%CI 1.059-9.073, P=0.011) were related factors of somatizations. Conclusions: The incidence of somatization symptoms is high in patients with psychological disorders in outpatients of cardiology department in general hospital. Anxiety, depression and gender are the main related risk factors of somatization symptoms in this patient cohort. Degree of anxiety and depression increased in proportion to the severity of somatization symptoms. Anxiety, depression and female is related to somatization symptoms.


Asunto(s)
Hospitales Generales , Pacientes Ambulatorios , Adulto , Ansiedad , Estudios Transversales , Depresión , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
3.
Nano Lett ; 18(4): 2623-2629, 2018 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-29529377

RESUMEN

It is well-known that superconductivity in thin films is generally suppressed with decreasing thickness. This suppression is normally governed by either disorder-induced localization of Cooper pairs, weakening of Coulomb screening, or generation and unbinding of vortex-antivortex pairs as described by the Berezinskii-Kosterlitz-Thouless (BKT) theory. Defying general expectations, few-layer NbSe2, an archetypal example of ultrathin superconductors, has been found to remain superconducting down to monolayer thickness. Here, we report measurements of both the superconducting energy gap Δ and critical temperature TC in high-quality monocrystals of few-layer NbSe2, using planar-junction tunneling spectroscopy and lateral transport. We observe a fully developed gap that rapidly reduces for devices with the number of layers N ≤ 5, as does their TC. We show that the observed reduction cannot be explained by disorder, and the BKT mechanism is also excluded by measuring its transition temperature that for all N remains very close to TC. We attribute the observed behavior to changes in the electronic band structure predicted for mono- and bi- layer NbSe2 combined with inevitable suppression of the Cooper pair density at the superconductor-vacuum interface. Our experimental results for N > 2 are in good agreement with the dependences of Δ and TC expected in the latter case while the effect of band-structure reconstruction is evidenced by a stronger suppression of Δ and the disappearance of its anisotropy for N = 2. The spatial scale involved in the surface suppression of the density of states is only a few angstroms but cannot be ignored for atomically thin superconductors.

4.
Nat Commun ; 8: 14552, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28211517

RESUMEN

An energy gap can be opened in the spectrum of graphene reaching values as large as 0.2 eV in the case of bilayers. However, such gaps rarely lead to the highly insulating state expected at low temperatures. This long-standing puzzle is usually explained by charge inhomogeneity. Here we revisit the issue by investigating proximity-induced superconductivity in gapped graphene and comparing normal-state measurements in the Hall bar and Corbino geometries. We find that the supercurrent at the charge neutrality point in gapped graphene propagates along narrow channels near the edges. This observation is corroborated by using the edgeless Corbino geometry in which case resistivity at the neutrality point increases exponentially with increasing the gap, as expected for an ordinary semiconductor. In contrast, resistivity in the Hall bar geometry saturates to values of about a few resistance quanta. We attribute the metallic-like edge conductance to a nontrivial topology of gapped Dirac spectra.

5.
Br Poult Sci ; 57(1): 12-22, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26594822

RESUMEN

The aim of the study was to evaluate the effects of microbial aerosols on ducks' welfare and provide information on which to establish microbial aerosol concentration standards for poultry. A total of 1800 1-d-old Cherry Valley ducks were randomly divided into 5 groups (A, B, C, D and E) with 360 ducks in each. To obtain objective data, each group had three replications. Different microbial aerosol concentrations in different groups were created by controlling ventilation and bedding cleaning frequency. Group A was the control group and hygienic conditions deteriorated progressively from group B to E. A 6-stage Andersen impactor was used to detect the aerosol concentration of aerobes, fungi, gram-negative bacteria and an AGI-30 microbial air sampler detected endotoxins. Physiological stress was evaluated in the ducks by adrenocorticotropic hormone (ACTH) values in serum. To assess the effects of bioaerosol factors, welfare indicators including fluctuating asymmetry (FA), appearance and gait as well as the Lactobacillus caecal concentration were evaluated. The data showed group D had already reached the highest limit of concentration of airborne aerobic bacteria, airborne fungi, airborne gram-negative bacteria and airborne endotoxin. The ducks in this group had significantly increased serum ACTH values and significantly decreased caecal lactobacilli concentration. Furthermore, appearance and gait scores, wing length and overall FA and caecal Lactobacillus concentration in this group were significantly increased at 6 and 8 weeks of age. In conclusion, high concentrations of microbial aerosol adversely affected the welfare of meat ducks. The microbial aerosol values in group D suggest a preliminary upper limit concentration of bioaerosols in ambient air for healthy meat ducks.


Asunto(s)
Aerosoles , Microbiología del Aire , Crianza de Animales Domésticos , Bienestar del Animal , Patos/fisiología , Aerosoles/normas , Microbiología del Aire/normas , Animales , China , Monitoreo del Ambiente , Distribución Aleatoria
6.
Nano Lett ; 15(10): 6991-5, 2015 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-26407106

RESUMEN

Few-layer black phosphorus was recently rediscovered as a narrow-bandgap atomically thin semiconductor, attracting unprecedented attention due to its interesting properties. One feature of this material that sets it apart from other atomically thin crystals is its structural in-plane anisotropy which manifests in strongly anisotropic transport characteristics. However, traditional angle-resolved conductance measurements present a challenge for nanoscale systems, calling for new approaches in precision studies of transport anisotropy. Here, we show that the nonlocal response, being exponentially sensitive to the anisotropy value, provides a powerful tool for determining the anisotropy in black phosphorus. This is established by combining measurements of the orientation-dependent nonlocal resistance response with the analysis based on the anamorphosis relations. We demonstrate that the nonlocal response can differ by orders of magnitude for different crystallographic directions even when the anisotropy is at most order-one, allowing us to extract accurate anisotropy values.

7.
Nano Lett ; 15(8): 4914-21, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26132110

RESUMEN

Many layered materials can be cleaved down to individual atomic planes, similar to graphene, but only a small minority of them are stable under ambient conditions. The rest react and decompose in air, which has severely hindered their investigation and potential applications. Here we introduce a remedial approach based on cleavage, transfer, alignment, and encapsulation of air-sensitive crystals, all inside a controlled inert atmosphere. To illustrate the technology, we choose two archetypal two-dimensional crystals that are of intense scientific interest but are unstable in air: black phosphorus and niobium diselenide. Our field-effect devices made from their monolayers are conductive and fully stable under ambient conditions, which is in contrast to the counterparts processed in air. NbSe2 remains superconducting down to the monolayer thickness. Starting with a trilayer, phosphorene devices reach sufficiently high mobilities to exhibit Landau quantization. The approach offers a venue to significantly expand the range of experimentally accessible two-dimensional crystals and their heterostructures.

8.
Science ; 346(6208): 448-51, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25342798

RESUMEN

Topological materials may exhibit Hall-like currents flowing transversely to the applied electric field even in the absence of a magnetic field. In graphene superlattices, which have broken inversion symmetry, topological currents originating from graphene's two valleys are predicted to flow in opposite directions and combine to produce long-range charge neutral flow. We observed this effect as a nonlocal voltage at zero magnetic field in a narrow energy range near Dirac points at distances as large as several micrometers away from the nominal current path. Locally, topological currents are comparable in strength with the applied current, indicating large valley-Hall angles. The long-range character of topological currents and their transistor-like control by means of gate voltage can be exploited for information processing based on valley degrees of freedom.

9.
Nano Lett ; 14(6): 3270-6, 2014 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-24844319

RESUMEN

Hexagonal boron nitride is the only substrate that has so far allowed graphene devices exhibiting micrometer-scale ballistic transport. Can other atomically flat crystals be used as substrates for making quality graphene heterostructures? Here we report on our search for alternative substrates. The devices fabricated by encapsulating graphene with molybdenum or tungsten disulfides and hBN are found to exhibit consistently high carrier mobilities of about 60 000 cm(2) V(-1) s(-1). In contrast, encapsulation with atomically flat layered oxides such as mica, bismuth strontium calcium copper oxide, and vanadium pentoxide results in exceptionally low quality of graphene devices with mobilities of ∼1000 cm(2) V(-1) s(-1). We attribute the difference mainly to self-cleansing that takes place at interfaces between graphene, hBN, and transition metal dichalcogenides. Surface contamination assembles into large pockets allowing the rest of the interface to become atomically clean. The cleansing process does not occur for graphene on atomically flat oxide substrates.

10.
Nature ; 497(7451): 594-7, 2013 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-23676678

RESUMEN

Superlattices have attracted great interest because their use may make it possible to modify the spectra of two-dimensional electron systems and, ultimately, create materials with tailored electronic properties. In previous studies (see, for example, refs 1-8), it proved difficult to realize superlattices with short periodicities and weak disorder, and most of their observed features could be explained in terms of cyclotron orbits commensurate with the superlattice. Evidence for the formation of superlattice minibands (forming a fractal spectrum known as Hofstadter's butterfly) has been limited to the observation of new low-field oscillations and an internal structure within Landau levels. Here we report transport properties of graphene placed on a boron nitride substrate and accurately aligned along its crystallographic directions. The substrate's moiré potential acts as a superlattice and leads to profound changes in the graphene's electronic spectrum. Second-generation Dirac points appear as pronounced peaks in resistivity, accompanied by reversal of the Hall effect. The latter indicates that the effective sign of the charge carriers changes within graphene's conduction and valence bands. Strong magnetic fields lead to Zak-type cloning of the third generation of Dirac points, which are observed as numerous neutrality points in fields where a unit fraction of the flux quantum pierces the superlattice unit cell. Graphene superlattices such as this one provide a way of studying the rich physics expected in incommensurable quantum systems and illustrate the possibility of controllably modifying the electronic spectra of two-dimensional atomic crystals by varying their crystallographic alignment within van der Waals heterostuctures.

11.
Proc Natl Acad Sci U S A ; 110(9): 3282-6, 2013 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-23401538

RESUMEN

Capacitance measurements provide a powerful means of probing the density of states. The technique has proved particularly successful in studying 2D electron systems, revealing a number of interesting many-body effects. Here, we use large-area high-quality graphene capacitors to study behavior of the density of states in this material in zero and high magnetic fields. Clear renormalization of the linear spectrum due to electron-electron interactions is observed in zero field. Quantizing fields lead to splitting of the spin- and valley-degenerate Landau levels into quartets separated by interaction-enhanced energy gaps. These many-body states exhibit negative compressibility but the compressibility returns to positive in ultrahigh B. The reentrant behavior is attributed to a competition between field-enhanced interactions and nascent fractional states.

12.
Plant Biol (Stuttg) ; 11(3): 483-9, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19470119

RESUMEN

Effects of clonal integration on land plants have been extensively studied, but little is known about the role in amphibious plants that expand from terrestrial to aquatic conditions. We simulated expansion from terrestrial to aquatic habitats in the amphibious stoloniferous alien invasive alligator weed (Alternanthera philoxeroides) by growing basal ramets of clonal fragments in soils connected (allowing integration) or disconnected (preventing integration) to the apical ramets of the same fragments submerged in water to a depth of 0, 5, 10 or 15 cm. Clonal integration significantly increased growth and clonal reproduction of the apical ramets, but decreased both of these characteristics in basal ramets. Consequently, integration did not affect the performance of whole clonal fragments. We propose that alligator weed possesses a double-edged mechanism during population expansion: apical ramets in aquatic habitats can increase growth through connected basal parts in terrestrial habitats; however, once stolon connections with apical ramets are lost by external disturbance, the basal ramets in terrestrial habitats increase stolon and ramet production for rapid spreading. This may contribute greatly to the invasiveness of alligator weed and also make it very adaptable to habitats with heavy disturbance and/or highly heterogeneous resource supply.


Asunto(s)
Amaranthaceae/crecimiento & desarrollo , Amaranthaceae/fisiología , Ecosistema , Biomasa , Hojas de la Planta/crecimiento & desarrollo , Reproducción/fisiología , Suelo , Agua
13.
Neuroscience ; 140(3): 969-79, 2006 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-16650938

RESUMEN

Cysteinyl leukotrienes are potent pro-inflammatory mediators. Cysteinyl leukotriene receptor 1 is one of the two cysteinyl leukotriene receptors cloned. We recently reported that cysteinyl leukotriene receptor 1 antagonists protected against cerebral ischemic injury, and an inducible expression of cysteinyl leukotriene receptor 1 was found in neuron- and glial-appearing cells after traumatic injury in human brain. To determine the role of cysteinyl leukotriene receptor 1 in ischemic brain injury, we investigated the temporal and spatial profile of cysteinyl leukotriene receptor 1 expression in rat brain from 3 h to 14 days after 30 min of middle cerebral artery occlusion, and observed the effect of pranlukast, a cysteinyl leukotriene receptor 1 antagonist, on the ischemic injury. We found that cysteinyl leukotriene receptor 1 mRNA expression was up-regulated in the ischemic core both 3-12 h and 7-14 days, and in the boundary zone 7-14 days after reperfusion. In the ischemic core, cysteinyl leukotriene receptor 1 was primarily localized in neurons 24 h, and in macrophage/microglia 14 days after reperfusion; while in the boundary zone it was localized in proliferated astrocytes 14 days after reperfusion. Pranlukast attenuated neurological deficits, reduced infarct volume and ameliorated neuron loss in the ischemic core 24 h after reperfusion; it reduced infarct volume, ameliorated neuron loss and inhibited astrocyte proliferation in the boundary zone 14 days after reperfusion. Thus, we conclude that cysteinyl leukotriene receptor 1 mediates acute neuronal damage and subacute/chronic astrogliosis after focal cerebral ischemia.


Asunto(s)
Isquemia Encefálica/inmunología , Infarto Cerebral/inmunología , Encefalitis/inmunología , Gliosis/inmunología , Proteínas de la Membrana/genética , Degeneración Nerviosa/inmunología , Receptores de Leucotrienos/genética , Animales , Astrocitos/inmunología , Astrocitos/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatología , Infarto Cerebral/metabolismo , Infarto Cerebral/fisiopatología , Cromonas/farmacología , Modelos Animales de Enfermedad , Encefalitis/metabolismo , Encefalitis/fisiopatología , Gliosis/metabolismo , Gliosis/fisiopatología , Infarto de la Arteria Cerebral Media/inmunología , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/fisiopatología , Mediadores de Inflamación/metabolismo , Antagonistas de Leucotrieno/farmacología , Leucotrienos/inmunología , Leucotrienos/metabolismo , Masculino , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/fisiopatología , ARN Mensajero/inmunología , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión , Factores de Tiempo , Regulación hacia Arriba/inmunología
14.
Biochemistry ; 41(35): 10810-8, 2002 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-12196020

RESUMEN

Kinetic and structural data are presented on the interaction with Torpedo californica acetylcholinesterase (TcAChE) of (+)-huperzine A, a synthetic enantiomer of the anti-Alzheimer drug, (-)-huperzine A, and of its natural homologue (-)-huperzine B. (+)-Huperzine A and (-)-huperzine B bind to the enzyme with dissociation constants of 4.30 and 0.33 microM, respectively, compared to 0.18 microM for (-)-huperzine A. The X-ray structures of the complexes of (+)-huperzine A and (-)-huperzine B with TcAChE were determined to 2.1 and 2.35 A resolution, respectively, and compared to the previously determined structure of the (-)-huperzine A complex. All three interact with the "anionic" subsite of the active site, primarily through pi-pi stacking and through van der Waals or C-H.pi interactions with Trp84 and Phe330. Since their alpha-pyridone moieties are responsible for their key interactions with the active site via hydrogen bonding, and possibly via C-H.pi interactions, all three maintain similar positions and orientations with respect to it. The carbonyl oxygens of all three appear to repel the carbonyl oxygen of Gly117, thus causing the peptide bond between Gly117 and Gly118 to undergo a peptide flip. As a consequence, the position of the main chain nitrogen of Gly118 in the "oxyanion" hole in the native enzyme becomes occupied by the carbonyl of Gly117. Furthermore, the flipped conformation is stabilized by hydrogen bonding of Gly117O to Gly119N and Ala201N, the other two functional elements of the three-pronged "oxyanion hole" characteristic of cholinesterases. All three inhibitors thus would be expected to abolish hydrolysis of all ester substrates, whether charged or neutral.


Asunto(s)
Acetilcolinesterasa/química , Alcaloides/química , Inhibidores de la Colinesterasa/química , Medicamentos Herbarios Chinos/química , Sesquiterpenos/química , Torpedo , Acetilcolinesterasa/aislamiento & purificación , Animales , Unión Competitiva , Bryopsida/química , Cristalización , Cristalografía por Rayos X , Ligandos , Sustancias Macromoleculares , Unión Proteica , Estereoisomerismo , Relación Estructura-Actividad
15.
Circ Res ; 89(12): 1161-7, 2001 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11739281

RESUMEN

Vascular endothelial growth inhibitor (VEGI), a new member of the tumor necrosis factor family, is an endothelial cell-specific gene and a potent inhibitor of endothelial cell proliferation, angiogenesis, and tumor growth. We report here that VEGI mediates the following two activities in endothelial cells: early G(1) arrest in G(0)/G(1) cells responding to growth stimuli, and programmed death in proliferating cells. G(0)/G(1)-synchronized bovine aortic endothelial cells were treated with VEGI before and after the onset of the growth cycle. When the cells were stimulated with growth conditions but treated simultaneously with VEGI, a reversible, early-G(1) growth arrest occurred, evidenced by the lack of late G(1) markers such as hyperphosphorylation of the retinoblastoma gene product and upregulation of the c-myc gene. Additionally, VEGI treatment led to inhibition of the activities of cyclin-dependent kinases CDK2, CDK4, and CDK6. In contrast, VEGI treatment of cells that had entered the growth cycle resulted in apoptotic cell death, as evidenced by terminal deoxytransferase labeling of fragmented DNA, caspase 3 activation, and annexin V staining, all of which were lacking in nonproliferating cells treated with VEGI. Additionally, stress-signaling proteins p38 and JNK were not as fully activated by VEGI in quiescent as compared with proliferating populations. These findings suggest a dual role for VEGI, the maintenance of growth arrest and induction of apoptosis, in the modulation of the endothelial cell cycle.


Asunto(s)
Apoptosis , Quinasas CDC2-CDC28 , Endotelio Vascular/metabolismo , Proteínas Proto-Oncogénicas , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis/efectos de los fármacos , Biomarcadores/análisis , Caspasa 3 , Caspasas/metabolismo , Bovinos , Recuento de Células , División Celular/efectos de los fármacos , División Celular/fisiología , Células Cultivadas , Quinasa 2 Dependiente de la Ciclina , Quinasa 4 Dependiente de la Ciclina , Quinasa 6 Dependiente de la Ciclina , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Quinasas Ciclina-Dependientes/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Fase G1/efectos de los fármacos , Humanos , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , Especificidad de Órganos , /metabolismo , ARN Mensajero/metabolismo , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Especificidad de la Especie , Timidina/metabolismo , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/farmacología
16.
Hunan Yi Ke Da Xue Xue Bao ; 26(5): 405-8, 2001 Oct 28.
Artículo en Chino | MEDLINE | ID: mdl-12536482

RESUMEN

OBJECTIVE: To investigate effects of losartan, fosinopril and amlodipine on cardiomyocyte apoptosis, cardiac remolding in the spontaneously hypertensive rats (SHR). METHODS: SHRs were treated with lorsartan (SHR-L), fosinopril (SHR-F), amlodipine (SHR-A), and untreated (SHR-C) respectively for 8 and 16 weeks. Cardiomyocyte apoptotic index (APOI), left ventricular mass, left ventricular mass index (LVM, LVMI), and plasma and myocardium angiotensin II(PAng II, MAng II) concentrations were examined. RESULTS: 1. The systolic blood pressure was decreased similarly in all treatment groups in 8 and 16 weeks. LVMIs were reduced significantly in all treatment groups. LVMI was significantly lower in SHR-F group than that in other two treatment groups in 16 weeks. 2. APOIs were decreased significantly in SHR-F group in 8 weeks and in all treatment groups, especially in SHR-F group in 16 weeks. 3. Compared with SHR-C group in both periods, PAng II and MAng II were significantly increased in SHR-L group, but MAng II concentration was only decreased significantly in SHR-F group in 8 weeks, and in SHR-F and SHR-A groups in 16 weeks. CONCLUSION: Losartan, amlodipine, and especially fosinopril can inhibit cardiomyocyte apoptosis, prevent myocardial fibrosis, and reverse heart hypertrophy. Inhibition of myocardium rennin--angiotension--aldsteron system may be the mechanism of the three drugs' cardioprotective effects.


Asunto(s)
Antihipertensivos/farmacología , Apoptosis/efectos de los fármacos , Cardiotónicos/farmacología , Hipertensión/patología , Remodelación Ventricular/efectos de los fármacos , Amlodipino/farmacología , Animales , Femenino , Fosinopril/farmacología , Hipertensión/fisiopatología , Losartán/farmacología , Masculino , Miocitos Cardíacos/citología , Distribución Aleatoria , Ratas , Ratas Endogámicas SHR
17.
Hunan Yi Ke Da Xue Xue Bao ; 26(2): 118-20, 2001 Apr 28.
Artículo en Chino | MEDLINE | ID: mdl-12536639

RESUMEN

OBJECTIVE: To investigate effects of lorsartan, fosinopril on myocardial fibrosis, angiotensin II and cardiac remolding in the spontaneously hypertensive rats (SHR). METHODS: 16-week-old SHRs were divided randomly into 3 groups: SHR-L (treated with lorsartan), SHR-F (treated with fosinopril) and SHR-C (untreated), each group consisting of 10 rats. After 8 weeks' and 16 weeks' therapeutic period, collagen volume fraction (CVF), perivascular circumferential area (PVCA), plasma and myocardium angiotensin II concentrations were examined by pathological examination with computed processing and radioimmunoassay respectively. RESULTS: (1) Compared with SHR-C after 8 weeks' and 16 weeks' therapeutic period, the systolic blood pressure (SBP) was decreased similarly in both treatment groups. Heart and left ventricular weights, heart weight and eft ventricular mass indexes were lower significantly in both treatment groups than in SHR-C. Left ventricular mass index was reduced to a lower extent in SHR-F group than in SHR-L group after 16 weeks. (2) Compared with SHR-C, CVF, PVCA after 8 weeks and 16 weeks were reduced significantly in SHR-F and SHR-L. Meanwhile, CVF after 16 weeks in SHR-F than in SHR-L. (3) Compared with SHR-C after both therapeutic periods, plasma and myocardium angiotensin II concentrations were increased Significantly in SHR-L, but plasma angiotensin II concentrations were not altered significantly in SHR-F. However, myocardium angiotensin II concentrations were reduced significantly in SHR-F after 8 weeks and 16 weeks in SHR-F. CONCLUSION: Lorsartan, fosinopril inhibit myocardial fibrosis and reverse heart hypertrophy. Fosinopril may be more effective in these above effects than Lorsartan. The mechanism of the both drug's cardioprotective effects was related to inhibition of myocardium rennin-angiotension-aldsteron system.


Asunto(s)
Angiotensina II/metabolismo , Antihipertensivos/farmacología , Fosinopril/farmacología , Hipertensión , Losartán/farmacología , Miocardio/patología , Animales , Fibrosis , Hipertensión/patología , Hipertensión/fisiopatología , Masculino , Distribución Aleatoria , Ratas , Ratas Endogámicas SHR , Remodelación Ventricular
18.
Oncogene ; 18(47): 6496-504, 1999 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-10597252

RESUMEN

Recently a new member of the human tumor necrosis factor (TNF) family named as VEGI was reported. However, very little is known about the biological activities displayed by this cytokine. In this report, we show that in myeloid cells VEGI activated the transcription factor kappa B (NF-kappa B) as determined by the electrophoretic mobility shift assay, induced degradation of I kappa B alpha, and nuclear translocation of p65 subunit of NF-kappa B. VEGI also activated NF-kappa B-dependent reporter gene expression. In addition, VEGI activated c-Jun N-terminal kinase. When examined for growth modulatory effects, VEGI inhibited the proliferation of breast carcinoma (MCF-7), epithelial (HeLa), and myeloid (U-937 and ML-1a) tumor cells; and activated caspase-3 leading to PARP cleavage. VEGI-induced cytotoxicity was potentiated by inhibitors of protein synthesis. VEGI also induced proliferation of normal human foreskin fibroblast cells. The activity of VEGI could neither be neutralized by antibodies against TNF, nor could it compete with TNF binding, indicating that the activity of VEGI is not due to TNF and it binds to a distinct receptor. These results suggest that VEGI, a new member of the TNF family, has a signaling pathway similar to TNF and is most likely a multifunctional cytokine.


Asunto(s)
División Celular/fisiología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo , Factor de Necrosis Tumoral alfa/fisiología , Secuencia de Bases , Cartilla de ADN , Activación Enzimática , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos , Unión Proteica , Proteínas Recombinantes/metabolismo , Miembro 15 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Factor de Necrosis Tumoral alfa/metabolismo
19.
Int J Cardiol ; 69(2): 133-7, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10549836

RESUMEN

The aim of this study was to evaluate nitrate tolerance in patients with coronary heart diseases by vascular ultrasonography and treadmill exercise. According to the dosage interval of isosorbide dinitrate, 66 patients with coronary heart disease were divided into group A and group B in a random, control and double-blind method. Isosorbide dinitrate was given every 6 hours in group A and every 12 hours in group B for one week. Before and after the therapeutic period, the diameters of brachial arteries were measured by vascular ultrasonography at baseline and 5 min after sublingual administration of 10 mg isosorbide dinitrate, and the treadmill exercise test was performed in all subjects. The results showed that diameters of brachial arteries were increased significantly after sublingual isosorbide dinitrate in both groups before the therapeutic period. After the therapeutic period, dilation of brachial arteries induced by sublingual isosorbide dinitrate was more marked in group B than in group A. Compared with those before the therapeutic period, sigmaST segment depression decreased and treadmill walking time increased significantly in group B but not in group A after the therapeutic period. These findings suggest that less frequent doses of isosorbide dinitrate may prevent development of nitrate tolerance, which is confirmed by vascular ultrasonography combined with treadmill exercise in patients with coronary heart disease.


Asunto(s)
Enfermedad Coronaria/tratamiento farmacológico , Tolerancia a Medicamentos , Dinitrato de Isosorbide/uso terapéutico , Vasodilatadores/uso terapéutico , Adulto , Anciano , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/efectos de los fármacos , Enfermedad Coronaria/diagnóstico por imagen , Método Doble Ciego , Prueba de Esfuerzo/efectos de los fármacos , Femenino , Humanos , Dinitrato de Isosorbide/administración & dosificación , Masculino , Persona de Mediana Edad , Ultrasonografía , Vasodilatadores/administración & dosificación
20.
Toxicol Appl Pharmacol ; 160(2): 198-205, 1999 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-10527919

RESUMEN

Several thiol-containing molecules (TCM) are currently used as antidotes for nickel, and vicinal TCM seem to be more effective in mobilizing tissue nickel than are mono TCM. Using single cell alkaline electrophoresis, we have shown that the vicinal TCM, meso-2, 3-dimercaptosuccinic acid (DMSA), 2,3-dimercaptopropane-1-sulfonate, and 2,3-dimercaptopropanol markedly enhanced, whereas the mono TCM, D-penicillamide, glutathione, beta-mercaptoethanol, and diethyl dithiocarbomate, reduced nickel chloride (Ni)-induced DNA breaks in a human leukemia cell line, NB4 cells. Ni or TCM alone did not induce plasmid DNA breaks in test tubes and neither did Ni plus mono TCM; however, Ni plus vicinal TCM did. Vicinal TCM did, but mono TCM did not generate H(2)O(2) in solution. H(2)O(2) alone did not, but H(2)O(2) plus Ni induced plasmid DNA breaks. Although Ni plus glutathione did not break DNA, Ni plus glutathione plus H(2)O(2) did. The Ni-DMSA-induced DNA breaks in NB4 cells, as well as in plasmids, were completely prevented by d-mannitol or partially prevented by several antioxidants. Therefore, the DNA breaks induced by Ni plus vicinal TCM seem to be due to the complex of Ni with TCM in concert with the H(2)O(2) produced by the vicinal TCM. The results that DMSA at a concentration as low as 5 microM enhanced the Ni-induced DNA breaks suggest a further evaluation of the TCM as nickel chelators is needed.


Asunto(s)
Daño del ADN , Níquel/toxicidad , Compuestos de Sulfhidrilo/farmacología , Línea Celular/efectos de los fármacos , Ensayo Cometa , Dimercaprol/farmacología , Ditiocarba/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Glutatión/farmacología , Humanos , Mercaptoetanol/farmacología , Níquel/antagonistas & inhibidores , Níquel/química , Níquel/farmacología , Oxidación-Reducción , Ácido Penicílico/análogos & derivados , Ácido Penicílico/farmacología , Plásmidos/efectos de los fármacos , Succímero/farmacología , Compuestos de Sulfhidrilo/química
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