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1.
Phys Rev Lett ; 125(7): 076401, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32857568

RESUMEN

In nodal-line semimetals, linearly dispersing states form Dirac loops in the reciprocal space with a high degree of electron-hole symmetry and a reduced density of states near the Fermi level. The result is reduced electronic screening and enhanced correlations between Dirac quasiparticles. Here we investigate the electronic structure of ZrSiSe, by combining time- and angle-resolved photoelectron spectroscopy with ab initio density functional theory (DFT) complemented by an extended Hubbard model (DFT+U+V) and by time-dependent DFT+U+V. We show that electronic correlations are reduced on an ultrashort timescale by optical excitation of high-energy electrons-hole pairs, which transiently screen the Coulomb interaction. Our findings demonstrate an all-optical method for engineering the band structure of a quantum material.

2.
Zhongguo Zhong Yao Za Zhi ; 45(17): 4154-4157, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-33164400

RESUMEN

Clinical practice guideline for Tripterygium Glycosides/Tripterygium wilfordii Tablets in the treatment of rheumatoid arthritis(T/CACM 1337-2020) was approved on June, 2020 by the Standardization Office of Chinese Association of Chinese Medicine. Our group developed this guideline for the clinical application of Tripterygium Glycosides/Tripterygium wilfordii Tablets according to the manual for the clinical experts consensus of Chinese patent medicine from January, 2018, when this project was approved by Chinese Association of Chinese Medicine. In this article, the detailed information on our compilation process was provided, in order to facilitate the understanding and the application of the guideline, as well as provide reference for the development of clinical practice guideline for other Chinese patent medicine.


Asunto(s)
Artritis Reumatoide , Medicamentos Herbarios Chinos , Artritis Reumatoide/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Glicósidos , Humanos , Comprimidos , Tripterygium
3.
Undersea Hyperb Med ; 42(5): 383-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26591977

RESUMEN

We are living in an environment full of gases, and any change in the concentration of a component of the air or contaminants (usually toxic) in the air may significantly threaten human health. Thus, to investigate the influence of gases in animal models it is helpful to elucidate the pathogenesis of gas-related injury. Although there are devices used for gas exposure in animals, there are still limitations in the establishment of these animal models, such as the change in gas concentration during the refreshing of water, food and litter, and the contamination of toxic gases released by animals. Herein, we freshly prepared a chamber for normobaric gas exposure. During the exposure in this chamber, the refreshing of water, food and litter does not require opening of the chamber. The chamber gases are continuously circulated and filtered, and the gas concentration remains very stable. To validate the feasibility of this chamber, rats were exposed to pure oxygen as an example. Results showed that rats with hyperoxia-induced lung injury simulated by pure oxygen exposure displayed the representative characteristics as observed in humans: shortness of breath, lung edema, alveolar septal rupture, infiltration of inflammatory cells, oxidative and inflammatory injury. This suggests that it is feasible to establish animal models using this chamber for the investigation of gas toxicity.


Asunto(s)
Cámaras de Exposición Atmosférica , Modelos Animales de Enfermedad , Hiperoxia/complicaciones , Lesión Pulmonar/complicaciones , Oxígeno , Amoníaco/análisis , Animales , Dióxido de Carbono/análisis , Monóxido de Carbono/análisis , Disnea/etiología , Ambiente Controlado , Diseño de Equipo , Estudios de Factibilidad , Glutatión/análisis , Sulfuro de Hidrógeno/análisis , Lesión Pulmonar/inducido químicamente , Malondialdehído/análisis , Estrés Oxidativo , Alveolos Pulmonares/lesiones , Edema Pulmonar/etiología , Ratas , Rotura/etiología
4.
Genet Mol Res ; 13(3): 7437-46, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25222243

RESUMEN

The association between the microsomal epoxide hydrolase 1 gene (EPHX1) Tyr113His polymorphism and lung cancer and breast cancer risk has been reported in many recent studies, but there is no consensus among the results. Thus, we examined the association between the EPHX1 Tyr113His polymorphism and lung cancer through a meta-analysis. A comprehensive literature search was performed using the Pubmed and Embase databases. Odds ratios with 95% confidence intervals were used to assess the strength of associations. Our meta-analysis suggested that the Tyr113His polymorphism was associated with lung cancer risk in Asians under 3 genetic models, including a C vs T, CC vs TT, and recessive model. However, the risk was decreased in Caucasians under the genetic models, including a C vs T, CC vs TT, or CT vs TT, dominant, and recessive model. In contrast, there was no association with breast cancer risk for any of the genetic models. Our meta-analysis suggested that the EPHX1 Tyr113His polymorphism may be a risk factor for lung cancer in Asians, whereas it may be a decreased risk factor among Caucasians. However, this polymorphism was not found to be associated with breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Epóxido Hidrolasas/genética , Estudios de Asociación Genética , Neoplasias Pulmonares/genética , Polimorfismo de Nucleótido Simple , Alelos , Sustitución de Aminoácidos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Masculino , Oportunidad Relativa , Sesgo de Publicación
5.
Undersea Hyperb Med ; 41(1): 27-31, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24649714

RESUMEN

Iron is essential to life due to its unusual flexibility in serving as both an electron donor and acceptor. However, free iron can damage tissues by catalyzing the conversion of hydrogen peroxide to free-radical ions that attack lipids, proteins and DNA. Hyperoxia-induced lung injury (HILI) occurs when breathing elevated partial pressure of oxygen (usually > 0.5 atmospheres absolute) for extended periods. A few studies have shown that iron and proteins related to iron metabolism are closely related to HILI, and iron chelation may exert protective effects on HILI. As a rate-limiting enzyme in the degradation of heme, heme oxygenases (HOs) play a crucial role in the iron metabolism. Although some studies have been conducted to investigate the role of HOs in the pathogenesis of HILI, findings still conflict, and HOs of different isoforms may function differently in the pathogenesis of HILI. On the available findings, there might be a beneficial threshold of HO-1 expression in HILI. More studies are required to confirm the above findings and to provide evidence for the clinical treatment of HILI by iron chelation.


Asunto(s)
Hemo Oxigenasa (Desciclizante)/metabolismo , Hiperoxia/complicaciones , Hierro/efectos adversos , Lesión Pulmonar/etiología , Animales , Humanos , Hiperoxia/metabolismo , Hierro/metabolismo , Quelantes del Hierro/administración & dosificación , Lesión Pulmonar/metabolismo , Lesión Pulmonar/prevención & control , Ratas
6.
QJM ; 116(3): 213-220, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36269193

RESUMEN

BACKGROUND: The incidence of infections among cancer patients is as high as 23.2-33.2% in China. However, the lack of information and data on the number of antibiotics used by cancer patients is an obstacle to implementing antibiotic management plans. AIM: This study aimed to investigate bacterial infections and antibiotic resistance in Chinese cancer patients to provide a reference for the rational use of antibiotics. DESIGN: This was a 5-year retrospective study on the antibiotic resistance of cancer patients. METHODS: In this 5-year surveillance study, we collected bacterial and antibiotic resistance data from 20 provincial cancer diagnosis and treatment centers and three specialized cancer hospitals in China. We analyzed the resistance of common bacteria to antibiotics, compared to common clinical drug-resistant bacteria, evaluated the evolution of critical drug-resistant bacteria and conducted data analysis. FINDINGS: Between 2016 and 2020, 216 219 bacterial strains were clinically isolated. The resistance trend of Escherichia coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, cefotaxime, piperacillin/tazobactam and imipenem was relatively stable and did not significantly increase over time. The resistance of Pseudomonas aeruginosa strains to all antibiotics tested, including imipenem and meropenem, decreased over time. In contrast, the resistance of Acinetobacter baumannii strains to carbapenems increased from 4.7% to 14.7%. Methicillin-resistant Staphylococcus aureus (MRSA) significantly decreased from 65.2% in 2016 to 48.9% in 2020. CONCLUSIONS: The bacterial prevalence and antibiotic resistance rates of E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, S. aureus and MRSA were significantly lower than the national average.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Neoplasias , Humanos , Staphylococcus aureus , Escherichia coli , Estudios Retrospectivos , Pacientes Internos , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias , Farmacorresistencia Bacteriana , Pseudomonas aeruginosa , Imipenem , China/epidemiología , Klebsiella pneumoniae , Neoplasias/complicaciones , Neoplasias/epidemiología , Neoplasias/tratamiento farmacológico
7.
Headache ; 51(2): 237-45, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20946428

RESUMEN

OBJECTIVE: The aim of this study was to investigate the possible microstructural abnormalities of the corpus callosum (CC) in adult patients with migraine without aura complicated with depressive/anxious disorder. BACKGROUND: Emotional disorders, especially depression and anxiety, are with relatively higher incidence in migraine population. However, the mechanism of migraine complicated with depressive/anxious disorder remains unclear. METHODS: Diffusion tensor magnetic resonance imaging was carried out in 12 adult patients with simple migraine (without aura and without depressive/anxious disorder) (S-M group), 12 adult patients with complicated migraine (without aura but complicated with depressive/anxious disorder) (Co-M group), and 12 age- and sex-matched healthy subjects (Control group). Fractional anisotropy (FA) and apparent diffusion coefficient were measured at genu, body, and splenium of the CC, respectively. RESULTS: There were significant differences in FA values at all locations of the CC among the 3 groups. The FA values from both the SM and Co-M groups were significantly lower than the control (P < .05 and P < .01, respectively). The FA values from Co-M group were significantly lower than the SM group (P < .01). The apparent diffusion coefficient values of the above regions had no significant differences among these groups (P > .05). There were negative correlations between FA value of genu of the CC and disease course as well as FA value of genu and body of the CC and headache frequency (P < .05). Negative correlations were also found between FA values at all locations of the CC and Hamilton anxiety and Hamilton depression scores (both P < .05). CONCLUSIONS: There might be an integrity change of neurofibrotic microstructures existing as a possible neuroanatomical basis in the CC of migraine patients complicated with depressive/anxious disorder.


Asunto(s)
Trastornos de Ansiedad/patología , Cuerpo Calloso/patología , Depresión/patología , Imagen de Difusión por Resonancia Magnética , Trastornos Migrañosos/patología , Adulto , Analgésicos/uso terapéutico , Antidepresivos/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico , Trastornos de Ansiedad/psicología , Estudios de Casos y Controles , Depresión/tratamiento farmacológico , Depresión/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/psicología
8.
Nat Commun ; 11(1): 1124, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32111848

RESUMEN

Experimental advances in the fabrication and characterization of few-layer materials stacked at a relative twist of small angle have recently shown the emergence of flat energy bands. As a consequence electron interactions become relevant, providing inroads into the physics of strongly correlated two-dimensional systems. Here, we demonstrate by combining large scale ab initio simulations with numerically exact strong correlation approaches that an effective one-dimensional system emerges upon stacking two twisted sheets of GeSe, in marked contrast to all moiré systems studied so far. This not only allows to study the necessarily collective nature of excitations in one dimension, but can also serve as a promising platform to scrutinize the crossover from two to one dimension in a controlled setup by varying the twist angle, which provides an intriguing benchmark with respect to theory. We thus establish twisted bilayer GeSe as an intriguing inroad into the strongly correlated physics of lowdimensional systems.

9.
Hepatol Res ; 39(4): 382-90, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19054141

RESUMEN

AIM: The effects of ischemic postconditioning (IPostC) on ischemia reperfusion (IR) injury of liver grafts was examined in rats after orthotopic liver transplantation (OLT). METHODS: Male Wistar rats were used as donors and recipients to establish a liver transplantation model. The animals were randomly divided into four groups: sham-operated (SO, n = 6), IR (n = 6), IPostC1 (n = 6) and IPostC2 (n = 6). IPostC was achieved by several intermittent interruptions of blood flow in the early phase of reperfusion. Several parameters of hepatic damage, oxidative stress, neutrophil infiltration and the expression of TNF-alpha and MIP-2 were detected as well as microscopic examination. Nitric oxide release and liver NO synthases (endothelial NO synthase and inducible NO synthase) expression were also measured. RESULTS: We observed that a significant reduction in alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase values in two IPostC groups when compared with IR group. The increases in hepatic malondialdehyde, and decreases in superoxide dismutase and reduced glutathione levels after orthotopic liver transplantation were significantly inhibited by IPostC. IR induced increase in hepatic myeloperoxidase content, TNF-alpha and MIP-2 expression were also lowered by IPostC. The increases in NO content and NOS protein expression were much more prominent in IPostC treated groups. Animals treated with IPostC presented minimal hemorrhage and reduced signs of liver injury. There was no significant difference between two IPostC treated groups. CONCLUSIONS: IPostC provided significant protection against IR injury to liver grafts. The protective effect of IPostC is closely related to the NO production following the increase in endothelial and inducible NO synthases expression and the suppression of tumor necrosis factor-alpha and macrophage inflammatory protein-2 overproduction.

10.
J Appl Microbiol ; 107(1): 245-56, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19302301

RESUMEN

AIMS: To clone and characterize genes encoding novel cellulases from metagenomes of buffalo rumens. METHODS AND RESULTS: A ruminal metagenomic library was constructed and functionally screened for cellulase activities and 61 independent clones expressing cellulase activities were isolated. Subcloning and sequencing of 13 positive clones expressing endoglucanase and MUCase activities identified 14 cellulase genes. Two clones carried two gene clusters that may be involved in the degradation of polysaccharide nutrients. Thirteen recombinant cellulases were partially characterized. They showed diverse optimal pH from 4 to 7. Seven cellulases were most active under acidic conditions with optimal pH of 5.5 or lower. Furthermore, one novel cellulase gene, C67-1, was overexpressed in Escherichia coli, and the purified recombinant enzyme showed optimal activity at pH 4.5 and stability in a broad pH range from pH 3.5 to 10.5. Its enzyme activity was stimulated by dl-dithiothreitol. CONCLUSIONS: The cellulases cloned in this work may play important roles in the degradation of celluloses in the variable and low pH environment in buffalo rumen. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provided evidence for the diversity and function of cellulases in the rumen. The cloned cellulases may at one point of time offer potential industrial applications.


Asunto(s)
Bacterias/enzimología , Celulasas/genética , Clonación Molecular/métodos , Metagenómica , Rumen/enzimología , Animales , Bacterias/genética , Búfalos , Electroforesis en Gel de Poliacrilamida , Biblioteca Genómica , Rumen/microbiología , Análisis de Secuencia de ADN
11.
Curr Mol Med ; 16(4): 353-93, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26980699

RESUMEN

BACKGROUND & OBJECTIVES: Chromatin structure is the single most important feature that distinguishes a cancer cell from a normal cell histologically. Chromatin remodeling proteins regulate chromatin structure and high mobility group A (HMGA1) proteins are among the most abundant, nonhistone chromatin remodeling proteins found in cancer cells. These proteins include HMGA1a/HMGA1b isoforms, which result from alternatively spliced mRNA. The HMGA1 gene is overexpressed in cancer and high levels portend a poor prognosis in diverse tumors. HMGA1 is also highly expressed during embryogenesis and postnatally in adult stem cells. Overexpression of HMGA1 drives neoplastic transformation in cultured cells, while inhibiting HMGA1 blocks oncogenic and cancer stem cell properties. Hmga1 transgenic mice succumb to aggressive tumors, demonstrating that dysregulated expression of HMGA1 causes cancer in vivo. HMGA1 is also required for reprogramming somatic cells into induced pluripotent stem cells. HMGA1 proteins function as ancillary transcription factors that bend chromatin and recruit other transcription factors to DNA. They induce oncogenic transformation by activating or repressing specific genes involved in this process and an HMGA1 "transcriptome" is emerging. Although prior studies reveal potent oncogenic properties of HMGA1, we are only beginning to understand the molecular mechanisms through which HMGA1 functions. In this review, we summarize the list of putative downstream transcriptional targets regulated by HMGA1. We also briefly discuss studies linking HMGA1 to Alzheimer's disease and type-2 diabetes. CONCLUSION: Further elucidation of HMGA1 function should lead to novel therapeutic strategies for cancer and possibly for other diseases associated with aberrant HMGA1 expression.


Asunto(s)
Crecimiento y Desarrollo/genética , Proteína HMGA1a/metabolismo , Neoplasias/genética , Transcriptoma/genética , Animales , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Proteína HMGA1a/genética , Humanos , Células Madre Pluripotentes/metabolismo
12.
Biochimie ; 87(11): 959-66, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15963621

RESUMEN

In the present study, we developed a mAb to alginate-derived polymannuronates (ADPM) and examined the antigenic epitopes using surface plasmon resonance (SPR) in conjunction with a large panel of oligomannuronate probes. We found that tetrasaccharide is the minimum-binding unit, and that increases in chain length from the tetrasaccharide to the heptsaccharide further enhance monovalent binding. A sharp increase in affinity was observed when increasing from the octasaccharide to the cosasaccharide, which is due to a further enhancement of the individual antigenic epitope combined with multivalency. Kinetic binding studies further suggested that the conformational epitope is discontinuous and infrequent and that a C6-carboxyl group is important in maintaining the conformational epitope. Moreover, CD analysis revealed there were conformational structures in epitopes. The data support our hypothesis that the conformational epitope for the mAb may be an extended helical segment of ADPM. ADPM exists mainly in linear form, but it can infrequently and spontaneously form extended helices. Although helices are not prevalent in ADPM, the immune system preferentially selects these conformational epitopes because they are unique. Together, our results indicate that the antigenic epitopes in beta-d-mannuronates are conformational and require C6-carboxyl groups.


Asunto(s)
Alginatos/química , Epítopos/química , Mananos/química , Animales , Anticuerpos Monoclonales , Conformación de Carbohidratos , Dicroismo Circular , Ratones , Oligosacáridos/química , Resonancia por Plasmón de Superficie
13.
J Dent Res ; 94(11): 1601-9, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26377571

RESUMEN

The present study aimed to investigate the therapeutic effect of injections of local bone marrow mesenchymal stem cells (BMSCs) on osteoarthritis (OA) of the temporomandibular joint (TMJ) and to explore the role of stromal cell-derived factor 1 (SDF-1) and regulated on activation, normal T-cell expressed and secreted (RANTES) in this effect. Fundamentally, OA of the TMJ was induced by unilateral anterior crossbite in mice. Exogenous green fluorescent protein-labeled BMSCs (GFP-BMSCs) were weekly injected into the TMJ region for 4, 8, and 12 wk. The reparative effects of exogenous GFP-BMSCs were investigated by morphological observation and micro-computed tomography. The differentiation of GFP-BMSCs in the cartilage was examined by double immunofluorescence of GFPs with type II collagen, and the expression of related factors in the condylar cartilage was quantified by real-time polymerase chain reaction. The role of RANTES and SDF-1 in the therapeutic effect of exogenous BMSCs was examined by both in vitro and in vivo studies. The OA cartilage of the TMJ displays a synchronous increase in SDF-1 and RANTES expression and a higher capability of attracting the migration of GFP-BMSCs. The implanted GFP-BMSCs differentiated into type II collagen-positive cells and reversed cartilage degradation and subchondral bone loss in mice with OA of the TMJ. The migration of GFP-BMSCs towards OA cartilage and the rescuing effect of GFP-BMSC injections were impaired by the inhibitors of C-X-C chemokine receptor type 4 (CXCR4) and C-C chemokine receptor type 1 (CCR1), which are the receptors of SDF-1 and RANTES, respectively. Our data indicated that SDF-1/CXCR4 and RANTES/CCR1 signals are pivotal and function synergistically in the recruitment of GFP-BMSCs towards degraded cartilage in mice OA of the TMJ.


Asunto(s)
Quimiocina CCL5/fisiología , Quimiocina CXCL12/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Osteoartritis/terapia , Trastornos de la Articulación Temporomandibular/terapia , Animales , Quimiocina CCL5/metabolismo , Quimiocina CXCL12/metabolismo , Colágeno Tipo II/fisiología , Modelos Animales de Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena en Tiempo Real de la Polimerasa , Resultado del Tratamiento , Microtomografía por Rayos X
14.
Nutrition ; 31(1): 171-5, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25441594

RESUMEN

OBJECTIVE: Early enteral nutrition is beneficial for acute pancreatitis (AP), but the optimal timing and criteria remain unclear. The aim of this study was to explore the feasibility and safety of early oral refeeding (EORF) based on hunger in patients with moderate or severe AP. METHODS: In a prospective, single-center, controlled, randomized clinical trial (ChiCTR-TRC-12002994), eligible patients with moderate or severe AP were randomized to either EORF or conventional oral refeeding (CORF). Patients in the EORF group restarted an oral diet when they felt hungry, regardless of laboratory parameters. Those in the CORF group restarted an oral diet only when clinical and laboratory symptoms had resolved. Clinical outcomes were compared between the two groups. RESULTS: In all, 146 eligible patients with moderate or severe AP were included and randomized to the EORF (n = 70) or CORF (n = 76) group. There were eight dropouts after randomization (three in EORF group; five in CORF group). The groups had similar baseline characteristics. The total length of hospitalization (13.7 ± 5.4 d versus 15.7 ± 6.2 d; P = 0.0398) and duration of fasting (8.3 ± 3.9 d versus 10.5 ± 5.1 d; P = 0.0047) were shorter in the EORF group than in the CORF group. There was no difference in the number of adverse events or complications between the two groups. The mean blood glucose level after oral refeeding was higher in the EORF group than in the CORF group (P = 0.0030). CONCLUSIONS: This controlled, randomized clinical trial confirmed the effectiveness and feasibility of EORF based on hunger in patients with moderate or severe AP. EORF could shorten the length of hospitalization in patients with moderate or severe AP.


Asunto(s)
Ingestión de Energía , Hambre , Pancreatitis/terapia , Enfermedad Aguda , Adulto , Anciano , Glucemia/metabolismo , Colesterol/sangre , Nutrición Enteral , Estudios de Factibilidad , Femenino , Hospitalización , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Triglicéridos/sangre , Adulto Joven
15.
Life Sci ; 75(10): 1181-93, 2004 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-15219806

RESUMEN

Meal timing can reset circadian clocks in peripheral tissues. We investigated the effects of such non-photic entrainment on tumor growth rate. Two experiments involved a total of 61 male B6D2F(1) mice synchronized with an alternation of 12 h of light (L) and 12 h of darkness (D) (LD12:12). Mice were randomly allocated to have access to food ad libitum, or restricted to 4 or 6 h during L or D. Rest-activity and body temperature, two circadian outputs, were monitored with an intra-peritoneal sensor. Glasgow osteosarcoma was inoculated into both flanks of each mouse ten days after meal timing onset. Before tumor inoculation, meal timing during D amplified the 24-h rhythms in rest-activity and body temperature with minimal phase alteration as compared to ad libitum feeding. Conversely, meal timing during L induced dominant 12-h or 8-h rhythmic components in activity, nearly doubled the 24-h amplitude of body temperature and shifted its acrophase (time of maximum) from approximately mid-D to approximately mid-L. Thirteen days after tumor inoculation, mean tumor weight (+/- SEM, mg) was 1503 +/- 150 in ad libitum mice, 1077 +/- 157 in mice fed during D and 577 +/- 139 in mice fed during L (ANOVA, p < 0.0001). Overall survival was prolonged in the mice fed during L (median, 17.5 days, d) as compared with those fed during D (14.5 d) or ad libitum (14 d) (Log Rank, p = 0.0035). The internal desynchronization produced by meal timing during L slowed down tumor progression, an effect possibly resulting from improved host-mediated tumor control and/or altered tumor circadian clocks.


Asunto(s)
Neoplasias Óseas/patología , Conducta Alimentaria , Osteosarcoma/patología , Animales , Temperatura Corporal/fisiología , Ritmo Circadiano , Progresión de la Enfermedad , Femenino , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Actividad Motora/fisiología , Trasplante de Neoplasias , Tasa de Supervivencia
16.
J Dent Res ; 93(2): 140-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24309371

RESUMEN

Emerging evidence has implied that subchondral bone plays an important role during osteoarthritis (OA) pathology. This study was undertaken to investigate whether abnormalities of the condylar subchondral bone lead to temporomandibular joint (TMJ) OA. We used an osteoblast-specific mutant TGF-ß1 transgenic mouse, the CED mouse, in which high levels of active TGF-ß1 occur in bone marrow, leading to abnormal bone remodeling. Subchondral bone changes in the mandibular condyles were investigated by micro-CT, and alterations in TMJ condyles were confirmed by histopathological and immunohistochemical analysis. Abnormalities in the condylar subchondral bone, characterized as fluctuant bone mineral density and microstructure and increased but uncoupled activity of osteoclasts and osteoblasts, were apparent in the 1- and 4-month CED mouse groups, while obvious cartilage degradation, in the form of cell-free regions and proteoglycan loss, was observed in the 4-month CED group. In addition, increased numbers of apoptotic chondrocytes and MMP9- and VEGF-positive chondrocytes were observed in the condylar cartilage in the 4-month CED group, but not in the 1-month CED group, compared with their respective age-matched controls. This study demonstrated that progressive degradation of mandibular condylar cartilage could be induced by the abnormal remodeling of the underlying subchondral bone during TMJOA progression.


Asunto(s)
Cóndilo Mandibular/patología , Osteoartritis/genética , Trastornos de la Articulación Temporomandibular/genética , Factor de Crecimiento Transformador beta/genética , Animales , Apoptosis/fisiología , Densidad Ósea/fisiología , Médula Ósea/patología , Remodelación Ósea/genética , Cartílago/patología , Estudios de Casos y Controles , Caspasa 3/análisis , Condrocitos/patología , Colágeno Tipo I/genética , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/genética , Metaloproteinasa 13 de la Matriz/análisis , Metaloproteinasa 9 de la Matriz/análisis , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos , Ratones Transgénicos , Osteoblastos/patología , Osteoclastos/patología , Proteoglicanos/análisis , Factor A de Crecimiento Endotelial Vascular/análisis , Microtomografía por Rayos X/métodos
17.
Afr Health Sci ; 13(3): 556-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24250288

RESUMEN

BACKGROUND: The glucuronidation process has been regarded as the key elimination process for toxic bile acids. UDP-glucuronosyltransferase (UGT) 1A3 is one important metabolizing enzyme involved in this process. OBJECTIVE: To evaluate the inhibition of UGT1A3 by scutellarein which is an important herbal ingredient using in vitro method, trying to indicate the possibility of toxicity due to the accumulation of toxic bile acids. METHODS: Due to the difficulty to gain the standards of biles acids' glucuronides, the recombinant UGT1A3-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction was employed to profile the activity of UGT1A3. RESULTS: The results showed that scutellarein inhibited UGT1A3 in a concentration-dependent behaviour. Competitive inhibition was demonstrated using both Dixon plot and Lineweaver-Burk plot, and the inhibition kinetic parameter (Ki) was calculated to be 5.8uM. CONCLUSION: All these data reminded the necessary monitoring of the levels of bile acids in plasma when utilizing scutellarein and the herbs containing this compound.


Asunto(s)
Apigenina/farmacología , Ácidos y Sales Biliares/metabolismo , Inhibidores Enzimáticos/farmacología , Glucuronosiltransferasa/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Himecromona , Metabolismo de los Lípidos/efectos de los fármacos
18.
J Clin Neurosci ; 17(5): 601-5, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20227278

RESUMEN

To exclude underlying vascular abnormalities in patients with spontaneous intracerebral hemorrhage, the traditional paradigm requires investigation using digital subtraction angiography (DSA) in both the acute and subacute phases. We investigated whether MRI and magnetic resonance angiography (MRA), in the subacute stage of intracerebral hematoma, had high positive predictive values (PPV) and negative predictive values (NPV) in screening for vascular abnormality in the routine clinical setting. In a regional neurosurgical center in Hong Kong, we retrospectively reviewed 151 patients investigated with both MRI and DSA for underlying structural vascular abnormalities during the subacute phase. Sensitivity, specificity, and intermodality agreement were assessed. A total of 70/151 (46%) vascular lesions accountable for the hemorrhage were found. Patients with vascular abnormalities tended to be younger (mean age+/-standard deviation [SD], 33+/-15years), less likely to be hypertensive (6.3%), and the lesion was more likely to be accompanied by intraventricular hemorrhage (22%). In terms of cerebral arteriovenous malformation and dural arteriovenous fistulas, MRI/MRA had a PPV of 0.98 and a NPV of 1.00. We concluded that MRI/MRA was able to detect most structural vascular abnormalities in the subacute phase in most patients and, thus, its use is recommended as the screening test.


Asunto(s)
Angiografía de Substracción Digital/métodos , Hemorragia Cerebral/diagnóstico por imagen , Angiografía por Resonancia Magnética/métodos , Adulto , Factores de Edad , Anciano , Fístula Arteriovenosa/complicaciones , Fístula Arteriovenosa/diagnóstico por imagen , Hemorragia Cerebral/etiología , Distribución de Chi-Cuadrado , Femenino , Hong Kong , Humanos , Procesamiento de Imagen Asistido por Computador , Malformaciones Arteriovenosas Intracraneales/complicaciones , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 13(4): 229-32, 1992 Aug.
Artículo en Zh | MEDLINE | ID: mdl-1338714

RESUMEN

A solid-phase immunosorbent hemagglutination inhibition test (SPISHAI) was developed for hepatitis A virus-specific immunoglobulin M (IgM) antibody. Three hundred thirty and six sera were comparatively detected with both SPISHAI and ELISA. Among them 97 sera were positive and 237 were negative with both method. The crude agreement rate was 99.4%. With SPISHAI the titers of anti-HAV IgM ranged from 1:20 to 1:327,680 among tested sera from infected individuals by HAV. The specificity of SPISHAI was confirmed by 2-ME treatment method and blocking test. The patients with non-A hepatitis all got negative results. The SPISHAI does not require conjugated antibody and sophisticated equipment, and is not interfered with rheumatoid factor in sera. Furthermore, the result of the test can be got within 3 hours. Therefore, the SPISHAI is a cheap and simple, and could be applied for early diagnosis and epidemiological surveillance of hepatitis A in the community and in primary health care.


Asunto(s)
Anticuerpos Antihepatitis/sangre , Hepatovirus/inmunología , Inmunoglobulina M/sangre , Pruebas de Inhibición de Hemaglutinación/métodos , Anticuerpos de Hepatitis A , Humanos , Técnicas de Inmunoadsorción
20.
Zhongguo Yao Li Xue Bao ; 19(4): 356-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10375784

RESUMEN

AIM: To study the effect of mitoxantrone (Mit) on DNA polymerases of tumor cells. METHODS: DNA polymerases of Ehrlich ascites carcinoma cells were isolated by phosphocellulose column chromatography. The effects of Mit on DNA polymerase alpha, beta, and gamma were detected by method of K Ono. RESULTS: Mit inhibited DNA polymerase alpha, beta, and gamma, IC50 values were 11.9, 6.5, and 11.9 mumol.L-1, and Ki 1.86, 2.22, and 2.05 mumol.L-1, respectively. The inhibitory mode of Mit on DNA polymerase alpha, beta, and gamma was competitive. CONCLUSION: Mit is a strong inhibitor on DNA polymerase alpha, beta, and gamma. The inhibitory mode was competition with respect to template DNA.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma de Ehrlich/enzimología , ADN Polimerasa Dirigida por ADN/metabolismo , Doxorrubicina/farmacología , Mitoxantrona/farmacología , Animales , Unión Competitiva , Carcinoma de Ehrlich/patología , ADN Polimerasa I/metabolismo , ADN Polimerasa beta/metabolismo , ADN Polimerasa gamma , Concentración 50 Inhibidora , Masculino , Ratones , Células Tumorales Cultivadas/enzimología
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