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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(9): 1510-1516, 2023 Sep 06.
Artículo en Chino | MEDLINE | ID: mdl-37743316

RESUMEN

Obstructive sleep apnea (OSA) is a sleep disorder with a high incidence and severe impact on the human body, which can induce systemic chronic inflammatory responses. Chronic inflammation is an important cause of exacerbation of OSA and its associated complications. Nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) is an inflammasome that is widely found in epithelial cells and immune cells and plays an important role in inflammatory diseases as an important component of innate immunity. Research evidence suggests that the activation of NLRP3 inflammasomes can exacerbate the damage to neurons, endothelial cells, lung and kidney caused by OSA, and these effects can be eliminated by genetic or pharmacological deletion of NLRP3. Targeting inhibition of NLRP3 inflammasome may serve as a co-therapeutic strategy for OSA-induced related complications. This article reviews NLRP3 inflammasome and its mechanism in OSA-related concurrent diseases, which can provide scientific basis for prevention and intervention of OSA and its related complications.


Asunto(s)
Inflamasomas , Apnea Obstructiva del Sueño , Humanos , Células Endoteliales , Proteína con Dominio Pirina 3 de la Familia NLR , Inflamación , Nucleótidos
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(6): 784-793, 2022 Jun 06.
Artículo en Chino | MEDLINE | ID: mdl-35785860

RESUMEN

Objective: To analyze the prevalence of allergic rhinitis in Chinese children from 2001 to 2021, in order to provide data support for the prevention and treatment of allergic rhinitis in children. Methods: "Allergic rhinitis" "children" "adolescent" "infant" "prevalence" "epidemiology" were used in the main search terms. The combination of Mesh words and free words was adopted. CNKI, CBM, VIP, WanFang Data, PubMed, Web of Science, Embase and The Cochrane Library for publications between January 1, 2001 and December 31, 2021 were searched systemically and data were extracted from eligible studies by two independent reviewers. Supplementary collection was made by identifying retrospective references from the included literature. After study quality assessment, Meta analysis was completed using Stata 16.0 software. Results: A total of 20 cross-sectional studies were included, involving 54 886 cases. Meta analysis results showed that the overall prevalence of allergic rhinitis among the participants was 18.46% (95%CI:14.34%-22.59%). Subgroup analysis showed that the prevalence of allergic rhinitis from 2012 to 2021 (19.75%) was higher than that from 2001 to 2011 (14.81%), and the difference was statistically significant (P<0.001). The prevalence of different regions from high to low was East China (22.77%), North China (20.82%), Northwest China (17.77%), Central China (16.62%), Southwest China (16.33%), Northeast China (16.16%) and South China (7.29%) respectively, the difference was statistically significant (P<0.001). The prevalence of male (20.73%) was higher than that of female (16.34%), and the difference was statistically significant (P<0.001). The prevalence of Han nationality(17.31%) was higher than that of ethnic minorities (15.93%), and the difference was statistically significant (P<0.001). Conclusion: The prevalence of allergic rhinitis in Chinese children is high and the prevalence in children varies by publication year, region, sex and nationality.


Asunto(s)
Rinitis Alérgica , Rinitis , Adolescente , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Estudios Retrospectivos , Rinitis Alérgica/epidemiología
3.
Eur Rev Med Pharmacol Sci ; 23(7): 2777-2785, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31002128

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) is a malignant cancer with a high fatality rate, and the expression of microRNA-145 (miR-145) is significantly low in HCC tissue. Therefore, the effect of miR-145 on HCC was explored. PATIENTS AND METHODS: Primary hepatocellular carcinoma samples and corresponding normal samples, and HepG2 cells were analyzed using flow cytometry, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Real-time quantitative reverse transcription-polymerase chain reaction, Western blotting, and dual-luciferase reporter assay. RESULTS: miR-145 expression was significantly downregulated in HCC tissue and HepG2 cells as compared to normal liver tissue. After HepG2 cells were transfected with miR-145 mimics, miR-145 expression was recovered, accompanied by a significantly lower cell number, inhibition of the G1/S phase transition, and promotion of the apoptosis of HepG2 cells, as well as changes in levels of G1/S-specific cyclin-E1 (CCNE1) and activated caspase-3. Furthermore, the rho-associated protein kinase 1 (ROCK1) levels were opposite the levels of miR-145 expression in vivo and in vitro, and additional experiments with co-transfection of miR-145 mimics and pEGFP-N3-3'UTR provided the direct evidence that the ROCK1 gene is a target of miR-145. Moreover, a significant decrease or increase in the expression of ROCK1 was associated with nuclear factor-kB (NF-κB)(p65) activity, and lipopolysaccharide (LPS) significantly increased NF-κB(p65) activity, accompanied by recovery of the reduction in the number of HepG2 cells for miR-145 mimics. The NF-κB activity and cell number were significantly (p < 0.05, p < 0.01) increased in response to the overexpression of the ROCK1 gene in HepG2 cells. CONCLUSIONS: We showed that miR-145 can target and downregulate ROCK1 expression, and it controls HCC by inhibiting the cell cycle and activating apoptosis via the ROCK1/NF-κB signaling pathway. Our findings will provide a new perspective for the therapy of HCC.


Asunto(s)
Apoptosis , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/patología , MicroARNs/genética , Estudios de Casos y Controles , Ciclo Celular , Proliferación Celular , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Células Hep G2/metabolismo , Humanos , Factor de Transcripción ReIA/metabolismo , Quinasas Asociadas a rho/metabolismo
4.
Eur Rev Med Pharmacol Sci ; 22(23): 8324-8332, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30556873

RESUMEN

OBJECTIVE: The aim of this paper is to investigate the functions of long noncoding RNA (lncRNA) FOXF1 Adjacent Non-Coding Developmental Regulatory RNA (FENDRR) in the growth and aggressiveness of non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: The expression of FENDRR in NSCLC tissues and cell lines was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and colony formation assays were conducted to explore the roles of FENDRR on the growth of NSCLC cell. The wound healing and transwell invasion assays were conducted to explore the impact of FENDRR on NSCLC cell migration and invasion. The apoptosis of NSCLC cell was detected using flow cytometer-based Annexin V/Propidium Iodide (PI) dual staining. The xenograft model was conducted to investigate the effect of FENDRR on the growth of NSCLC cell in vivo. The expression of Ki67 was measured by immunohistochemical (IHC) staining using Ki67 antibody. Bioinformatics analysis and Luciferase reporter assay were applied to identify that miR-761 was the target of FENDRR. Additional, colony formation and transwell experiments were utilized to confirm that FENDRR inhibited the growth and aggressiveness of NSCLC cell by regulating miR-761. RESULTS: We found a marked down-regulation of FENDRR in NSCLC tissues compared to tumor-adjacent tissues. FENDRR down-expression was detected in four NSCLC cell lines (H1650, HCC827, H1975 and A549) compared to the human non-tumorigenic bronchial epithelial cell, BEAS-2B. Low expression of FENDRR was identified as a predictive factor for poor prognosis of patients with NSCLC. The over-regulation of FENDRR inhibited the proliferation, migration and invasion capacities of NSCLC cell and promoted the apoptosis of NSCLC cell in vitro whereas the down-regulation of FENDRR caused the opposite results. Moreover, the over-expression of FENDRR restrained the growth of NSCLC cell in vivo. We found that there were potential binding sites between FENDRR and miR-761 and the level of miR-761 was inversely associated with the expression of ENDRR in NSCLC tissues. Finally, the rescue experiments suggested that the anti-oncogenic role of FENDRR was at least partially mediated by miR-761 in NSCLC. CONCLUSIONS: We found that FENDRR was down-expressed in NSCLC and the over-expression of FENDRR inhibited the malignant phenotypes of NSCLC cell by binding to miR-761 competitively.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Movimiento Celular , Proliferación Celular , Neoplasias Pulmonares/metabolismo , MicroARNs/metabolismo , ARN Largo no Codificante/metabolismo , Células A549 , Animales , Apoptosis , Sitios de Unión , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones Desnudos , MicroARNs/genética , Invasividad Neoplásica , ARN Largo no Codificante/genética , Transducción de Señal
6.
Skin Res Technol ; 23(4): 607-612, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28514014

RESUMEN

PURPOSE: To investigate the repeatability of vessel density measurement at human arm skin in healthy subjects with OCT-based microangiography (OMAG). METHODS: Four locations including volar wrist, volar forearm, shoulder, and volar upper arm were scanned using an optimized swept source OCT system, working at center wavelength of 1300 nm and A-line rate of 100 kHz. Three scans were acquired at each location at the same visit. Vascular images of papillary dermis, reticular dermis, and the whole dermis layer were generated with OMAG processing and automatic segmentation algorithms. The vessel density (VD) of each layer was calculated based on vascular images, and the repeatability of the VD at the same physiological location was thereafter assessed. RESULTS: Fifteen healthy volunteers were included. High repeatability of VD was found for wrist, forearm, shoulder, and upper arm (coefficient of variation (CV)=2.4, 2.7, 2.7, 2.0, and intraclass correlation coefficient (ICC)=0.906, 0.854, 0.943, 0.916 respectively). The VD measurements showed no significant difference between the four locations in any of the three layers, ie papillary layer (P=.1063), reticular layer (P=.3371), and whole dermis layer (P=.3233). CONCLUSION: Quantification of VD by using OCT/OMAG is repeatable when imaging skin tissue beds in healthy individuals.


Asunto(s)
Piel/irrigación sanguínea , Adulto , Análisis de Varianza , Angiografía , Femenino , Voluntarios Sanos , Humanos , Masculino , Microvasos/diagnóstico por imagen , Estudios Prospectivos , Reproducibilidad de los Resultados , Tomografía de Coherencia Óptica , Adulto Joven
7.
Genet Mol Res ; 14(1): 1957-67, 2015 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-25867341

RESUMEN

Isoflavonoids and the related synthesis enzyme, chalcone isomerase 1 (CHI1), are unique in the Leguminosae, with diverse biological functions. Among the Leguminosae, the soybean is an important oil, protein crop, and model plant. In this study, we aimed to detect the generation pattern of Leguminosae CHI1. Genome-wide sequence analysis of CHI in 3 Leguminosae and 3 other closely related model plants was performed; the expression levels of soybean chalcone isomerases were also analyzed. By comparing positively selected sites and their protein structures, we retrieved the evolution patterns for Leguminosae CHI1. A total of 28 CHI and 7 FAP3 (CHI4) genes were identified and separated into 4 clades: CHI1, CHI2, CHI3, and FAP3. Soybean genes belonging to the same chalcone isomerase subfamily had similar expression patterns. CHI1, the unique chalcone isomerase subfamily in Leguminosae, showed signs of significant positive selection as well as special expression characteristics, indicating an accelerated evolution throughout its divergence. Eight sites were identified as undergoing positive selection with high confidence. When mapped onto the tertiary structure of CHI1, these 8 sites were observed surrounding the enzyme substrate only; some of them connected to the catalytic core of CHI. Thus, we inferred that the generation of Leguminosae CHI1 is dependent on the positively selected amino acids surrounding its catalytic substrate. In other words, the evolution of CHI1 was driven by specific selection or processing conditions within the substrate.


Asunto(s)
Evolución Molecular , Glycine max/enzimología , Glycine max/genética , Liasas Intramoleculares/genética , Proteínas de Plantas/genética , Selección Genética , Secuencia de Aminoácidos , Clonación Molecular , Genoma de Planta , Liasas Intramoleculares/metabolismo , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/metabolismo , Estructura Terciaria de Proteína , Glycine max/clasificación
8.
Opt Lett ; 37(10): 1625-7, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22627517

RESUMEN

We report on a noninvasive and noncontact all-optical method to measure the elasticity of the cornea. We use a pulsed laser to excite surface acoustic waves (SAW) that propagate on the corneal surface, then use a phase-sensitive optical coherence tomography system to remotely record the SAWs from which the corneal elasticity is estimated. In addition, the system is able to provide real-time tomographic images of the cornea being examined, an important consideration for clinical studies. While precisely maintaining a range of intraocular pressures (IOP), a series of measurements is performed on ex vivo intact primate eyes. The measurement results not only demonstrate the feasibility of the proposed system to remotely measure the corneal elasticity, but also suggest a strong correlation between the corneal stiffness and the true IOP.


Asunto(s)
Córnea , Elasticidad , Fenómenos Ópticos , Acústica , Animales , Córnea/fisiología , Estudios de Factibilidad , Haplorrinos , Presión Intraocular , Rayos Láser
9.
Genet Mol Res ; 10(4): 3664-73, 2011 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-22180067

RESUMEN

Strigolactones are newly discovered plant hormones that perform various functions, from signaling in symbiotic interactions with arbuscular mycorrhizal fungi to controlling outgrowth of axillary buds. We examined the phylogenetic relationships of two carotenoid cleavage dioxygenase genes (CCD7 and CCD8) that are involved in consecutive upstream steps of the proposed strigolactone biosynthesis pathway. The CCD7 and CCD8 sequences from 11 model species, divided into two clades, correspond to sequences from monocotyledons and dicotyledons. However, the sequences from the primitive moss, Physcomitrella patens, appeared to be evolutionarily distinct from those of the angiosperms. CCD7 and CCD8 are much conserved, since no significant positive selection was detected among these plants. Ks values indicated that CCD7 and CCD8 diverged about 290 to 430 million years ago. As essential genes in the strigolactone pathway, the divergence timing of the conserved CCD7 and CCD8 genes reflects the approximate time of generation of strigolactone as a regulatory substance. This timing calculation also coincides with initiation of symbiosis between plants and microorganisms, inferred from the fossil record. Molecular evolution analyses of genes in metabolic pathways can provide insight concerning gene evolution.


Asunto(s)
Carotenoides/metabolismo , Dioxigenasas/genética , Evolución Molecular , Genes de Plantas/genética , Lactonas/metabolismo , Plantas/enzimología , Plantas/genética , Terpenos/metabolismo , Secuencia de Bases , Exones/genética , Variación Genética , Intrones/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Selección Genética , Análisis de Secuencia de ADN , Factores de Tiempo
10.
Tissue Eng ; 13(2): 323-31, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17518566

RESUMEN

Tendon tissue engineering requires the generation of a uniaxially orientated collagen type I matrix with several organization scales that confer mechanical functionality upon the tendon. A combination of factors in a dose- and time-dependent manner, such as growth factors and mechanical environment, may be the key to an in vitro-engineered tendon. To define the progress of tissue development within a scaffold, on-line systems need to be applied to monitor the newly generated matrix. To address this challenge, we designed a new porous chitosan scaffold with microchannels (diameter: 250 microm), which allows primary porcine tenocytes to proliferate in a bundle-like structure. The cell proliferation and extracellular matrix (ECM) production within the microchannels were successfully assessed under sterile conditions using optical coherence tomography (OCT). A semi-quantitative method that calculated the microchannel occupation ratio (the degree of cell proliferation and tissue turnover based on the total backscattered intensity in the microchannels) was developed. We further investigated the effect of different culture conditions on tendon cell matrix formation. Using a perfusion bioreactor, we demonstrated how fluid flow can increase (p < 1e(3)) ECM production within the microchannels significantly more than static culture. Our study illustrates how using a guiding scaffold in combination with the fast and non-destructive assessment of the microstructure using OCT allows discrimination between the parameters affecting the production and the organization of the ECM.


Asunto(s)
Quitosano/química , Tendones/citología , Tendones/crecimiento & desarrollo , Ingeniería de Tejidos/métodos , Tomografía de Coherencia Óptica/métodos , Animales , Materiales Biocompatibles/química , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Porcinos
11.
J Appl Microbiol ; 99(4): 934-44, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16162246

RESUMEN

AIMS: The effect of laser (pulse repetition frequency, pulse energy and exposure time) and environmental parameters (pH, NaCl concentration and wet or dry samples) of Nd:YAG laser decontamination of stainless steel inoculated with Escherichia coli, Staphylococcus aureus and Listeria monocytogenes was investigated. METHODS AND RESULTS: Stainless steel discs were inoculated with the bacterial samples and exposed to laser energy densities to about 900 J cm(-2). These inactivation curves allowed selection of laser parameters for two-level multifactorial designed experiments, the results of which allowed comparisons to be made between effects of individual and combined parameters on the laser inactivation efficiency. Escherichia coli was inactivated most effectively as a wet film with L. monocytogenes and S. aureus showing similar response. For the multifactorial experiments all laser parameters were significant and were smallest for S. aureus as a wet film. CONCLUSIONS: pH and NaCl concentration had little effect on the efficacy of laser inactivation but dry or wet states and all laser parameters were significant. SIGNIFICANCE AND IMPACT OF THE STUDY: Such systems may prove to be applicable in industrial processes where stainless steel may be contaminated with acidic solutions or salt, e.g. in the food industry with laser inactivation seeming to be independent of these parameters. Parameters have been identified that allow optimization of the treatment process.


Asunto(s)
Bacterias/efectos de la radiación , Descontaminación/métodos , Ambiente , Rayos Láser , Acero Inoxidable , Análisis de Varianza , Bacterias/crecimiento & desarrollo , Recuento de Colonia Microbiana/métodos , Medios de Cultivo , Contaminación de Equipos/prevención & control , Escherichia coli/crecimiento & desarrollo , Escherichia coli/efectos de la radiación , Humedad , Concentración de Iones de Hidrógeno , Listeria monocytogenes/crecimiento & desarrollo , Listeria monocytogenes/efectos de la radiación , Cloruro de Sodio/análisis , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/efectos de la radiación , Factores de Tiempo
12.
Biosens Bioelectron ; 20(3): 414-23, 2004 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-15494219

RESUMEN

The engineering of human tissue represents a major paradigm shift in clinical medicine. Early embodiments of tissue engineering are currently being taken forward to the clinic by production methods that are essentially extensions of laboratory manual procedures. However, to achieve the status of routine large-scale clinical practice, automation and scale-out processes are required. This in turn will require the development of reliable on-line monitoring and control systems. This paper examines one demand of crucial importance, namely the real time in vitro monitoring of the flow characteristics through growing tissue since this has a complex interrelationship. Doppler optical coherence tomography (DOCT) is a recently developed imaging technique for studying the rheological properties of tissues in vivo. Capable of non-invasive imaging in real time with high resolution, it is potentially ideal for the continuous monitoring of engineered tissues in vitro. As a base line, the current status of DOCT in vivo is therefore reviewed. This paper also reports the first preliminary use of DOCT in tissue engineering. The application described involves the imaging of a fully developed laminar flow through a combined tissue fabrication/bioreactor with a tissue-engineered construct (substitute blood vessel) in situ.


Asunto(s)
Vasos Sanguíneos/citología , Vasos Sanguíneos/fisiología , Flujometría por Láser-Doppler/métodos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Ingeniería de Tejidos/métodos , Tomografía de Coherencia Óptica/métodos , Reactores Biológicos , Velocidad del Flujo Sanguíneo/fisiología , Técnicas de Cultivo de Célula/métodos , Células Cultivadas , Humanos
13.
Phys Med Biol ; 49(7): 1097-115, 2004 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-15128192

RESUMEN

The better repair of human tissue is an urgent medical goal and in order to achieve a safe outcome there is a parallel need for sensitive, non-invasive methods of assessing the quality of the engineered tissues and organs prior to surgical implantation. Optical coherence tomography (OCT) can potentially fulfil this role. The current status of OCT as an advanced imaging tool in clinical medicine, developmental biology and material science is reviewed and the parallels to the engineering of living tissue and organs are discussed. Preliminary data are also presented for a tissue engineering bioreactor with in situ OCT imaging. The data suggest that OCT can be utilized as a real time, non-destructive, non-invasive tool to critically monitor the morphology of tissue-engineered constructs during their fabrication and growth.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Técnicas de Cultivo de Célula/tendencias , Células Cultivadas/citología , Ingeniería de Tejidos/métodos , Ingeniería de Tejidos/tendencias , Tomografía de Coherencia Óptica/métodos , Tomografía de Coherencia Óptica/tendencias , Animales , Reactores Biológicos , División Celular , Tamaño de la Célula , Predicción , Humanos
14.
J Xray Sci Technol ; 10(3): 167-76, 2002 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-22388046

RESUMEN

The highly scattering nature of human tissue limits light penetration depth in the near infrared range, which prevents the deeper microstructures from imaging. In order to enhance the imaging depth for the current high resolution optical imaging techniques, the light scattering in tissue must be reduced. This paper demonstrates that the light scattering of tissue can be effectively reduced by the topical applications of the biocompatible chemical agents. In this study the propylene glycol and glucose solutions were chosen for the demonstrations through topical applications and intra-dermis injection, respectively. The experiments were performed in vitro and in vivo by the use of the optical coherence tomography system. The results clearly show that the OCT imaging depth and contrast are dramatically improved after the topical applications of propylene glycol solution. Such improvement was discussed on the basis of refractive index matching environment created by the chemical agents, which effectively reduces the light scattering of tissue. Rayleigh-Gans approximation of light scattering was also used to show theoretically how the increase of refractive index of background medium would have effect on the reduced scattering coefficient of tissue. The theoretical and experimental results were qualitatively consistent.

15.
J Opt Soc Am A Opt Image Sci Vis ; 18(1): 224-31, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11152001

RESUMEN

The least-scattered photons that arrive at a detector through highly scattering tissues have the potential to image internal structures, functions, and status with high imaging resolution. In contrast, optical diffusing tomography is based on the use of the late-arriving photons, which have been diffusely scattered, leading to very low imaging resolution. A good model of the early-arriving photons, i.e., the least-scattered photons, may have a significant effect on the development of imaging algorithms and a further understanding of imaging mechanisms within current high-resolution optical-imaging techniques. We describe a vertex/propagator approach that attempts to find the probabilities for least-scattered photons traversing a scattering medium, based on analytical expressions for photon histories. The basic mathematical derivations for the model are outlined, and the results are discussed and found to be in very good agreement with those from the Monte Carlo simulations.

16.
J Appl Microbiol ; 89(3): 517-25, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11021585

RESUMEN

Infra-red light (1064 nm) from a high-power Nd:YAG laser caused more than 90% loss of viability of Escherichia coli during exposures that raised the temperature of PBS suspensions of the bacteria to 50 C in a thermocouple-equipped cuvette. In contrast, there was minimal loss of viability after heating the same suspensions to 50 degrees C in a water-bath, or in a PCR thermal cycler. The mechanism of laser killing at 50 degrees C was explored by differential scanning calorimetry, by laser treatment of transparent and turbid bacterial suspensions, and by optical absorbency studies of E. coli suspensions at 1064 nm. Taken together, the data suggested that the bactericidal action of Nd:YAG laser light at 50 degrees C was due partly to thermal heating and partly to an additional, as yet undefined, mechanism. Scanning electron microscopy revealed localized areas of surface damage on laser-exposed E. coli cells.


Asunto(s)
Escherichia coli/efectos de la radiación , Rayos Láser , Recuento de Colonia Microbiana , Escherichia coli/fisiología , Calefacción , Microscopía Electrónica
17.
Appl Opt ; 37(31): 7342-51, 1998 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18301568

RESUMEN

After analytical expressions for the time-resolved reflectance are introduced from the diffusion approximation under the three most commonly used boundary conditions, a novel algorithm is demonstrated for determining the reduced scattering and the absorption coefficients from time-resolved reflectance (or backscatter) measurements at two positions on the surface of biotissue. The algorithm is straightforward and fast and involves only some simple mathematical operations, avoiding complicated iterative nonlinear fitting to the time-resolved curve. The derived reduced scattering coefficient is not affected by whatever boundary condition is applied. The algorithm was verified with time-resolved data from the Monte Carlo model. Both a semi-infinite medium and a turbid slab medium were tested. In contrast to the nonlinear fitting method, this algorithm allows both the scattering and the absorption coefficients to be determined to a high accuracy.

18.
Yao Xue Xue Bao ; 32(7): 511-4, 1997 Jul.
Artículo en Chino | MEDLINE | ID: mdl-11596276

RESUMEN

Effects of ethanol at different dosages on hepatic antioxidative and detoxicating functions and the antagonizing effect of sodium ferulate have been investigated in mice. The data showed that ethanol (11.4 g.kg-1, ig) could induce the increase of hepatic glutathione peroxidase (GSH-Px) activity and decreases of hepatic glutathione reductase (GSH-Re), superoxide dismutase (SOD) and glutathione S-transferase (GST) activities and reduce glutathione (GSH) content. At the same time, serum GST activity was increased. Pretreatment with sodium ferulate (100 mg.kg-1 ig, qd x 10 d) completely reversed these changes induced by ig ethanol in mice, indicating that sodium ferulate could protect mice from ethanol-induced acute hepatotoxicity. The hepato-protective mechanism of sodium ferulate may be related to intensification of the function of glutathione oxidative-reductive enzymes, enhancement of SOD activity and promotion of glutathione conjugation. The results also indicate that the serum GST level is a sensitive indicator in ethanol-induced hepatotoxicity.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Ácidos Cumáricos/farmacología , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Hígado/metabolismo , Animales , Antioxidantes/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Etanol , Glutatión Reductasa/metabolismo , Masculino , Ratones , Superóxido Dismutasa/metabolismo
20.
Appl Opt ; 35(2): 286-96, 1996 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-21069011

RESUMEN

A modified fringe-adjusted joint transform correlator is proposed that is able to accommodate noise in the input scene. The effect of noise in the input scene on the performance of the joint transform correlator is analyzed and quantified. When the target is embeddedin aseverely noise-corrupted input scene, it is shown that the proposed modified fringe-adjusted filter joint transform correlator delivers a better correlation performance and the capacity to accommodate this noise than does the fringe-adjusted filter-based correlator. When the power spectra of the input image and the reference image are subtracted from the power spectrum of the joint-input image, it is found that the noise effect on the output plane is independent of the objects in the input scene and originates from the convolution of the reference image and noise in the input scene.

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