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1.
J Eur Acad Dermatol Venereol ; 34(3): 542-548, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31568595

RESUMEN

BACKGROUND: In previous epidemiological study, the prevalence of atopic dermatitis (AD) was 12.94% among children aged 1-7 years by clinical diagnosis, whereas that was 4.76% and 3.51% using U.K., and Hanifin and Rajka diagnostic criteria. OBJECTIVE: We aimed to propose new diagnostic criteria for children and evaluate its efficiency in different populations. METHODS: We screened atopic features and analysed their correlation with AD using data from a previous study. A new set of diagnostic criteria for children in China was proposed and validated in 1031 children in outpatient clinics and 538 children in a birth cohort survey. Clinical diagnosis and atopic feature evaluation were performed face to face by dermatologists specialized in AD. Three criteria were compared for diagnostic efficiency using the clinical diagnosis as the reference. RESULTS: The new diagnostic criteria for children were based on (i) pruritus; (ii) 'typical morphology and distribution' or 'atypical morphology and distribution with xerosis'; and (iii) a chronic or chronically relapsing course. Compared to classical diagnostic criteria, the sensitivity of the new diagnostic criteria was significantly higher in the epidemiological survey and the clinical setting, especially obvious among mild and moderate AD. In the birth cohort, the new criteria showed similar sensitivity and specificity. CONCLUSION: The new criteria for children yielded higher sensitivity for the diagnosis of AD in the epidemiological survey and clinical setting, particularly for mild and moderate AD. Among the birth cohort with a complete medical history, three criteria showed similar sensitivity and specificity.


Asunto(s)
Dermatitis Atópica/diagnóstico , Niño , Preescolar , China/epidemiología , Dermatitis Atópica/epidemiología , Pruebas Diagnósticas de Rutina/normas , Estudios Epidemiológicos , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos
2.
Appl Opt ; 58(16): 4241-4249, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31251226

RESUMEN

In this work, to reveal the underlying mechanism of the influence of multifrequency vibration on the optical performance of diamond-turned optics, a systematic simulation investigation is performed using Fourier modal method and fast Fourier transformation based on a well-established surface topography model. Both the simulation results and the experimental observations demonstrate that the center area is the most heavily influenced region on the machined surface, which is closely associated with the distribution of the surface roughness under multifrequency vibration. The vibration amplitude has a visible impact on the specular reflectivity, and with an increase in vibration amplitude, the specular reflectivity in the center area obviously decreases, while the specular reflectivity in remote areas basically remains invariant. To eliminate the negative effect in relation to the vibration, a two-step process technology is developed that includes a strict spindle balance and the optimization of process parameters, particularly the depth of cut and the spindle speed. The cutting experiments further validate the effectiveness of the proposed technology for elimination of the negative effect concerning multifrequency vibration.

3.
Osteoarthritis Cartilage ; 27(9): 1257-1265, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31146016

RESUMEN

Obesity is a well-known primary risk factor for osteoarthritis (OA). In recent decades, the biomechanics-based theoretical paradigm for the pathogenesis of obesity-associated OA has been gradually but fundamentally modified. This modification is a result of accumulating evidence that biological factors also contribute to the etiology of the disease. The gut microbiota is a complicated ecosystem that profoundly influences the health of the host and can be modulated by the combined effects of environmental stimuli and genetic factors. Recently, enteric dysbacteriosis has been identified as a causal factor in the initiation and propagation of obesity-associated OA in animal models. Gut microbes and their components, microbe-associated lipid metabolites, and OA interact at both systemic and local levels through mechanisms that involve interplay with the innate immune system. However, the demonstration of causality in humans will require further studies. Nonetheless, probiotics, prebiotics, dietary habits and exercise, which aid the restoration of a healthy microbial community, are potential therapeutic approaches in the treatment of obesity-associated OA.


Asunto(s)
Microbioma Gastrointestinal , Obesidad/complicaciones , Osteoartritis/etiología , Microbioma Gastrointestinal/fisiología , Humanos , Obesidad/microbiología , Osteoartritis/microbiología
4.
J Eur Acad Dermatol Venereol ; 33(8): 1569-1576, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30989708

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is the most common skin disorder in infancy. However, the diagnosis and definite significance of infantile AD remains a debated issue. OBJECTIVE: To analyse the phenotypes of AD in infancy, to establish diagnostic criteria and to estimate the prevalence of this condition in China. METHODS: This is a multicentric study, in which 12 locations were chosen from different metropolitan areas of China. Following careful and complete history-taking and skin examination, the definite diagnosis of AD was made and the severity based on the SCORAD index was determined by local experienced dermatologists. Based on the detailed phenotyping, the major and representative clinical features of infantile AD were selected to establish the diagnostic criteria and evaluate their diagnostic efficacy. RESULTS: A total of 5967 infants were included in this study. The overall point prevalence of AD was 30.48%. The infantile AD developed as early as at the second month of life, and its incidence peaked in the third month of life at 40.81%. The proportion of mild, moderate and severe AD was 67.40%, 30.57% and 2.03%, respectively. The most commonly seen manifestations in the infantile AD were facial dermatitis (72.07%), xerosis (42.72%) and scalp dermatitis (27.93%). We established the novel diagnostic criteria of infants, which included: (i) onset after 2 weeks of birth; (ii) pruritus and/or irritability and sleeplessness comparable with lesions; and (iii) all two items above with one of the following items can reach a diagnosis of AD: (i) eczematous lesions distributed on cheeks and/or scalp and/or extensor limbs, and (ii) eczematous lesions on any other parts of body accompanied by xerosis. CONCLUSIONS: In China, the prevalence of AD in infancy is 30.48% according to clinical diagnosis of dermatologists. The novel Chinese diagnostic criteria for AD in infants show a higher sensitivity and comparable specificity.


Asunto(s)
Dermatitis Atópica/diagnóstico , Fenotipo , China/epidemiología , Dermatitis Atópica/epidemiología , Femenino , Humanos , Lactante , Masculino , Prevalencia
5.
Appl Opt ; 58(6): 1596-1605, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30874010

RESUMEN

In this work, the influence of tool edge waviness on the diffraction effect of diamond-turned optics is simulated theoretically and further validated experimentally. In simulation, a 3D surface topography model with consideration of the influence of tool edge waviness is established, in which the variation of tool edge profile is estimated by a linear model in relation to the cutting distance. The results show that the diffraction effect represented in simulation is consistent with the experimental observation. With the deterioration of tool edge waviness, the diffraction efficiency of the specular light decreases, but the high-order diffracted light intensively distributes in the horizontal direction on the receiving screen. Such observation can be attributed to the subgrating effect induced by the periodic duplication of the tool edge profile on the machined surface, which heavily depends on the deterioration of tool edge waviness. Finally, a waviness-controlled diamond tool is recommended to finish a diffraction-free optics by the diamond turning process. Moreover, the diffraction effect can also be employed to monitor the dynamic wear of the cutting tool in diamond turning.

6.
Protein Pept Lett ; 26(6): 449-457, 2019 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-30919764

RESUMEN

BACKGROUND: The significance of multi-site phosphorylation of BCL-2 protein in the flexible loop domain remains controversial, in part due to the lack of structural biology studies of phosphorylated BCL-2. OBJECTIVE: The purpose of the study is to explore the phosphorylation induced structural changes of BCL-2 protein. METHODS: We constructed a phosphomietic mutant BCL-2(62-206) (t69e, s70e and s87e) (EEEBCL- 2-EK (62-206)), in which the BH4 domain and the part of loop region was truncated (residues 2-61) to enable a backbone resonance assignment. The phosphorylation-induced structural change was visualized by overlapping a well dispersed 15N-1H heteronuclear single quantum coherence (HSQC) NMR spectroscopy between EEE-BCL-2-EK (62-206) and BCL-2. RESULTS: The EEE-BCL-2-EK (62-206) protein reproduced the biochemical and cellular activity of the native phosphorylated BCL-2 (pBCL-2), which was distinct from non-phosphorylated BCL-2 (npBCL-2) protein. Some residues in BH3 binding groove occurred chemical shift in the EEEBCL- 2-EK (62-206) spectrum, indicating that the phosphorylation in the loop region induces a structural change of active site. CONCLUSION: The phosphorylation of BCL-2 induced structural change in BH3 binding groove.


Asunto(s)
Proteínas Mutantes/química , Resonancia Magnética Nuclear Biomolecular/métodos , Proteínas Proto-Oncogénicas c-bcl-2/química , Apoptosis , Línea Celular , Escherichia coli/genética , Humanos , Modelos Moleculares , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación , Fosforilación , Unión Proteica , Dominios Proteicos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transfección
7.
Opt Express ; 27(2): 1326-1344, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30696200

RESUMEN

In the visible light band, the diffraction effect of a diamond-turned surface will cause the optical performance to heavily deteriorate. Due to the insufficient understanding of diffraction effect, post-treatment, such as polishing technology has to be fulfilled. To reveal the origins of diffraction effect of the diamond-turned surface under visible light, theoretical analyses are carried out with consideration of the influencing factors in diamond turning. Simulation results, coupled with experimental observations, demonstrate that the periodic components of surface roughness are responsible for the diffraction light distribution in the horizontal direction of the receiving screen. However, the aperiodic components of surface roughness, derived from defects in material matrix, result in the diffraction spots on the whole receiving screen. To directly eliminate the diffraction effect in diamond turning, a novel method-with control on tool edge quality, material defects, and processing parameters-is proposed. The measurement results prove the effectiveness of this method, and the diffraction-free surface finish without any post-treatment is successfully acquired.

8.
Nature ; 554(7690): 73-76, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29310123

RESUMEN

White-dwarf stars are the end product of stellar evolution for most stars in the Universe. Their interiors bear the imprint of fundamental mechanisms that occur during stellar evolution. Moreover, they are important chronometers for dating galactic stellar populations, and their mergers with other white dwarfs now appear to be responsible for producing the type Ia supernovae that are used as standard cosmological candles. However, the internal structure of white-dwarf stars-in particular their oxygen content and the stratification of their cores-is still poorly known, because of remaining uncertainties in the physics involved in stellar modelling codes. Here we report a measurement of the radial chemical stratification (of oxygen, carbon and helium) in the hydrogen-deficient white-dwarf star KIC08626021 (J192904.6+444708), independently of stellar-evolution calculations. We use archival data coupled with asteroseismic sounding techniques to determine the internal constitution of this star. We find that the oxygen content and extent of its core exceed the predictions of existing models of stellar evolution. The central homogeneous core has a mass of 0.45 solar masses, and is composed of about 86 per cent oxygen by mass. These values are respectively 40 per cent and 15 per cent greater than those expected from typical white-dwarf models. These findings challenge present theories of stellar evolution and their constitutive physics, and open up an avenue for calibrating white-dwarf cosmochronology.

9.
Analyst ; 140(3): 895-901, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25503796

RESUMEN

Back Scatter Interferometry (BSI) has been proposed to be a highly sensitive and versatile refractive index sensor usable for analytical detection of biomarker and protein interactions in solution. However the existing literature on BSI lacks a physical explanation of why protein interactions in general should contribute to the BSI signal. We have established a BSI system to investigate this subject in further detail. We contribute with a thorough analysis of the robustness of the sensor including unwanted contributions to the interferometric signal caused by temperature variation and dissolved gasses. We report a limit of the effective minimum detectability of refractive index at the 10(-7) level. Long term stability was examined by simultaneously monitoring the temperature inside the capillary revealing an average drift of 2.0 × 10(-7) per hour. Finally we show that measurements on protein A incubated with immunoglobulin G do not result in a signal that can be attributed to binding affinities as otherwise claimed in literature.


Asunto(s)
Inmunoglobulina G/metabolismo , Interferometría/métodos , Proteína Estafilocócica A/metabolismo , Técnicas Biosensibles , Humanos , Inmunoglobulina G/química , Unión Proteica , Refractometría , Proteína Estafilocócica A/química
10.
Int J Obes (Lond) ; 36(9): 1203-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22124446

RESUMEN

OBJECTIVE: Recent observational studies have reported that body fat distribution might be differentially associated with subclinical atherosclerosis. We previously reported that visceral fat area (VFA) ≥ 80 cm2 is the optimal cutoff for identifying abdominal obesity in Chinese subjects. We examined whether VFA ≥ 80 cm2 reflects the association between abdominal obesity and subclinical atherosclerosis, and if determination of the visceral fat quantity is useful for assessing subclinical atherosclerosis in asymptomatic individuals. METHODS AND RESULTS: Participants (N=1005, men 515, women 490, 34-66 years) free of cardiovascular disease underwent magnetic resonance imaging and carotid ultrasound assessment to quantify VFA and carotid intima-media thickness (C-IMT). Overweight/obese subjects (body mass index (BMI) ≥ 25.0 kg m(-2)) had a higher C-IMT than lean subjects (BMI <25.0 kg m(-2)) (P<0.01). Subjects with VFA ≥ 80 cm2 had significantly higher C-IMT than those without abdominal obesity regardless of BMI (P<0.01). By multivariate regression analysis adjusted for anthropometric measurements and cardiovascular risk factors, waist circumference but not BMI was independently correlated with C-IMT in men (P<0.001). Similar findings were observed with an accurate obesity indices adjusted model, which showed that VFA was an independent risk factor for increased C-IMT in men but not in women. CONCLUSIONS: VFA 80 cm2 effectively identified carotid atherosclerosis for both lean and obese individuals in middle-aged Chinese men.


Asunto(s)
Tejido Adiposo/patología , Pueblo Asiatico/estadística & datos numéricos , Enfermedades de las Arterias Carótidas/patología , Grosor Intima-Media Carotídeo/estadística & datos numéricos , Grasa Intraabdominal/patología , Obesidad/patología , Delgadez/patología , Adulto , Anciano , Composición Corporal , Distribución de la Grasa Corporal , Índice de Masa Corporal , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/epidemiología , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Valor Predictivo de las Pruebas , Factores de Riesgo , Delgadez/epidemiología
11.
Diabet Med ; 28(11): 1323-9, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21658124

RESUMEN

AIMS: The overwhelming majority of subjects with normal glucose regulation have the highest plasma glucose concentration at 30 minutes during oral glucose tolerance. We aimed to examine the association between increment of 30-min post-challenge glucose and albuminuria in participants with normal glucose regulation. METHODS: A population-based cross-sectional study was conducted in six communities in Shanghai between 2007 and 2008. A total of 3508 subjects with normal glucose regulation had complete data and were enrolled into the analysis. Among the selected subjects, only 1525 individuals (581 men, 944 women) were examined for their serum insulin levels. We assessed post-challenge blood glucose and insulin at 0, 30 and 120 min, urinary albumin and creatinine. The 30-min post-challenge glucose increment (Δ) was calculated as 30-min post-challenge glucose minus fasting plasma glucose, and albumin/creatinine ratio was used to reflect urinary albumin excretion. RESULTS: Multivariable logistic regression analysis revealed that the Δ30-min post-challenge glucose was independently associated with increased albumin/creatinine ratio in men with normal glucose regulation (OR = 1.08, P = 0.025), but not in women. Furthermore, multivariable linear regression analysis revealed that early-phase glucose disposition index was the main factor responsible for Δ30-min post-challenge glucose and explained 14-20% of the variance of Δ30-min post-challenge glucose in the two subgroups (P < 0.05). Notably, men had higher Δ30-min post-challenge glucose and lower early-phase glucose disposition index than women (all P < 0.001). CONCLUSIONS: The 30-min post-challenge plasma glucose increment is associated with urine albumin excretion in men with normal glucose regulation.


Asunto(s)
Albuminuria/metabolismo , Glucemia/metabolismo , Creatinina/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Anciano , Albuminuria/sangre , Albuminuria/orina , Índice de Masa Corporal , China/epidemiología , Creatinina/orina , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/orina , Ayuno , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Prevalencia , Factores de Riesgo , Factores Sexuales , Encuestas y Cuestionarios
13.
Oncogene ; 27(10): 1421-8, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-17724464

RESUMEN

The prosurvival Bcl-2-family member Bfl-1/A1 is a transcriptional target of nuclear factor-kappaB (NF-kappaB) that is overexpressed in many human tumors and is a means by which NF-kappaB inhibits apoptosis, but its mode of action is controversial. To better understand how Bfl-1 functions, we investigated its interaction with proapoptotic multidomain proteins Bax and Bak, and the BH3-only proteins Bid and tBid. We demonstrate that in living cells Bfl-1 selectively interacts with Bak and tBid, but not with Bax or Bid. Bfl-1/Bak interaction is functional as Bfl-1 suppressed staurosporine (STS)-induced apoptosis in wild-type and Bax-deficient cells, but not in Bak-/- cells. We also show that Bfl-1 blocks tumor necrosis factor-alpha (TNFalpha)-induced activation of Bax indirectly, via association with tBid. C-terminal deletion decreased Bfl-1's interaction with Bak and tBid and reduced its ability to suppress Bak- and tBid-mediated cell death. These data indicate that Bfl-1 utilizes different mechanisms to suppress apoptosis depending on the stimulus. Bfl-1 associates with tBid to prevent activation of proapoptotic Bax and Bak, and it also interacts directly with Bak to antagonize Bak-mediated cell death, similar to Mcl-1. Thus, part of the protective function of NF-kappaB is to induce Mcl-1-like activity by upregulating Bfl-1.


Asunto(s)
Proteína Proapoptótica que Interacciona Mediante Dominios BH3/antagonistas & inhibidores , Proteínas de Neoplasias/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Proteína Destructora del Antagonista Homólogo bcl-2/antagonistas & inhibidores , Apoptosis/fisiología , Línea Celular Transformada , Línea Celular Tumoral , Células HeLa , Humanos , Antígenos de Histocompatibilidad Menor , Proteína 1 de la Secuencia de Leucemia de Células Mieloides , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo
14.
Biosens Bioelectron ; 21(9): 1746-52, 2006 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-16256328

RESUMEN

The suitability of high resolution, in situ dc-sheet resistance monitoring (SRM) as a simplified and reliable sensing technique towards detection and tracking of protein immobilization has been explored. Non-specific adsorption of bovine serum albumin (BSA) onto a very thin gold film, acting as the sensing resistor, has been employed as a model system. For comparison, the novel sensing method was combined with surface plasmon resonance (SPR) spectroscopy, using the same flow cell and sensing surface. Two different, well known adsorption states, involving a composite layer of irreversibly and reversibly bound BSA, were clearly resolved by both methods. Clearly structured, pronounced and fully reproducible film resistance modulations have been resolved in the associated SRM data. The transition from reversibly bound BSA to the diluted protein phase is associated with an unusually large decrease in the dc-sheet resistance. The observed resistance modulation magnitude for an adsorbed BSA monolayer corresponds to approximately 1%, and up to 100 mOmega at a 10 Omega sensing resistor. The sheet resistance of irreversibly bound BSA was determined to 0.24 kOmega/cm2, and the associated specific resistivity estimated to 1-2x10(4) Omega cm.


Asunto(s)
Técnicas Biosensibles/métodos , Materiales Biocompatibles Revestidos/análisis , Impedancia Eléctrica , Electroquímica/métodos , Ensayo de Materiales/métodos , Metales/química , Albúmina Sérica Bovina/análisis , Adsorción , Técnicas Biosensibles/instrumentación , Materiales Biocompatibles Revestidos/química , Electroquímica/instrumentación , Ensayo de Materiales/instrumentación , Microelectrodos , Unión Proteica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Albúmina Sérica Bovina/química
15.
Opt Lett ; 30(10): 1138-40, 2005 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-15943292

RESUMEN

Dispersion limits performance in many optical systems. In surface plasmon resonance (SPR) biosensors, the sensing area is an optical element in which the dispersion depends on the effective refractive index of the biochemical compounds to be measured. We report a method of compensating for wavelength dispersion in SPR biosensors employing two integrated diffractive optical coupling elements in a polymer substrate. The dispersion compensation is achieved over the whole dynamic measurement range and provides a biosensor more robust to wavelength fluctuations than prism-coupler SPR systems. The concept can readily be employed in other types of sensor measuring refractive-index changes.


Asunto(s)
Algoritmos , Técnicas Biosensibles/métodos , Refractometría/instrumentación , Refractometría/métodos , Resonancia por Plasmón de Superficie/instrumentación , Resonancia por Plasmón de Superficie/métodos , Técnicas Biosensibles/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Óptica y Fotónica/instrumentación , Dispersión de Radiación
16.
J Nat Prod ; 68(3): 427-9, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15787451

RESUMEN

A new indigoid derivative, bisindigotin (1), with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-antagonistic activity was isolated from the ethanol extract of the Chinese medicinal herb Isatis indigotica. Its structure was determined by spectroscopic methods. In the human HepG2 hepatoma cell model, 1 (50 nM to 2 microM) was found to dose-dependently inhibit TCDD-induced ethoxyresorufin O-deethylase (EROD) activity.


Asunto(s)
Isatis/química , Dibenzodioxinas Policloradas/antagonistas & inhibidores , Carcinoma Hepatocelular , Citocromo P-450 CYP1A1/metabolismo , Humanos , Medicina Tradicional China , Modelos Biológicos , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química
17.
Artículo en Inglés | MEDLINE | ID: mdl-16869772

RESUMEN

In this paper we consider whether the dependency of metazoan cells on extracellular signals to maintain cell survival results in an important barrier that must be overcome during carcinogenesis. It is now generally accepted that a major barrier to cancer comes from the inability of cells to enter and progress through the cell cycle in a cell-autonomous fashion. Most of the oncogenes studied over the last two decades contribute to the ability of the cancer cell to enter and progress through the cell cycle in the absence of the instructional signals normally imparted by extracellular growth factors. Over the last two decades, it has begun to be appreciated that there is a second potential barrier to transformation. It appears that all cells in multicellular organisms need extracellular signals not only to initiate proliferation, but also to maintain cell survival. Every cell in our body expresses the proteins necessary to execute its own death by apoptosis. A cell will activate this apoptotic program by default unless it receives signals from the extracellular environment that allow the cell to suppress the apoptotic machinery it expresses. It now appears that the molecular basis of this suppression lies in the signaling pathways that regulate cellular nutrient uptake and direct the metabolic fate of those nutrients.


Asunto(s)
Neoplasias/metabolismo , Neoplasias/patología , Adenosina Trifosfato/biosíntesis , Animales , Apoptosis , Autofagia , Proliferación Celular , Supervivencia Celular , Glucosa/metabolismo , Sustancias de Crecimiento/metabolismo , Humanos , Lípidos/biosíntesis , Ratones , Modelos Biológicos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal
18.
Med Biol Eng Comput ; 42(5): 698-706, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15503972

RESUMEN

The paper presents an algorithm for reducing false alarms related to changes in arterial blood pressure (ABP) in intensive care unit (ICU) monitoring. The algorithm assesses the ABP signal quality, analyses the relationship between the electrocardiogram and ABP using a fuzzy logic approach and post-processes (accepts or rejects) ABP alarms produced by a commercial monitor. The algorithm was developed and evaluated using unrelated sets of data from the MIMIC database. By rejecting 98.2% (159 of 162) of the false ABP alarms produced by the monitor using the test set of data, the algorithm was able to reduce the false ABP alarm rate from 26.8% to 0.5% of ABP alarms, while accepting 99.8% (441 of 442) of true ABP alarms. The results show that the algorithm is effective and practical, and its use in future patient monitoring systems is feasible.


Asunto(s)
Artefactos , Cuidados Críticos/métodos , Monitoreo Fisiológico/instrumentación , Anciano , Anciano de 80 o más Años , Algoritmos , Presión Sanguínea , Electrocardiografía/métodos , Falla de Equipo , Reacciones Falso Negativas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procesamiento de Señales Asistido por Computador
19.
Comput Cardiol ; 29: 269-72, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-14686450

RESUMEN

The advent of implantable cardioverter defibrillators (ICDs) has resulted in significant reductions in mortality in patients at high risk for sudden cardiac death. Extensive related basic research and clinical investigation continue. ICDs typically record intracardiac electrograms and inter-beat intervals along with device settings during episodes of device delivery of therapy. Researchers wishing to study these data further have until now been limited to viewing paper plots. In support of multi-center clinical studies of patients with ICDs, we have developed a web based searchable ICD data archiving system, which allows users to use a web browser to upload ICD data from diskettes to a server where the data are automatically processed and archived. Users can view and download the archived ICD data directly via the web. The entire system is built from open source software. At present more than 500 patient ICD data sets have been uploaded to and archived in the system. This project will be of value not only to those who wish to conduct research using ICD data, but also to clinicians who need to archive and review ICD data collected from their patients.


Asunto(s)
Bases de Datos Factuales , Muerte Súbita Cardíaca/prevención & control , Desfibriladores Implantables , Internet , Estudios Multicéntricos como Asunto , Arritmias Cardíacas/epidemiología , Arritmias Cardíacas/patología , Arritmias Cardíacas/prevención & control , Computadores , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/patología , Electrocardiografía , Frecuencia Cardíaca/fisiología , Humanos , Procesamiento de Señales Asistido por Computador , Programas Informáticos
20.
Genes Dev ; 15(12): 1481-6, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11410528

RESUMEN

The BH3-only proteins Bim and Bad bind to the antiapoptotic Bcl-2 proteins and induce apoptosis in wild-type cells and cells from either bax(-/-) or bak(-/-) animals. In contrast, constitutively active forms of Bim and Bad failed to induce apoptosis in bax(-/-)bak(-/-) cells. Expression of Bax restored susceptibility of the cells to Bim and Bad. In addition, Bax but not Bim or Bad sensitized the bax(-/-)bak(-/-) cells to a wide variety of cell death stimuli including UV irradiation, chemotherapeutic agents, and ER stress. These results suggest that neither activation of BH3-only proteins nor suppression of pro-survival Bcl-2 proteins is sufficient to kill cells in the absence of both Bax and Bak. Furthermore, whereas mouse embryo fibroblasts (MEF) expressing only Bax or Bak displayed resistance to transformation, bax(-/-)bak(-/-) MEF were nearly as prone to oncogenic transformation as p53(-/-) MEF. Thus, the function of either Bax or Bak appears required to initiate most forms of apoptosis and to suppress oncogenic transformation.


Asunto(s)
Apoptosis , Proteínas Portadoras/metabolismo , Proteínas de la Membrana/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas/fisiología , Animales , Proteínas Reguladoras de la Apoptosis , Proteína 11 Similar a Bcl2 , Proteínas Portadoras/genética , Transformación Celular Neoplásica , Células Cultivadas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Mutagénesis , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteína Destructora del Antagonista Homólogo bcl-2 , Proteína X Asociada a bcl-2 , Proteína Letal Asociada a bcl
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