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1.
Phys Rev Lett ; 130(20): 203001, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37267576

RESUMEN

The 2S_{1/2} hyperfine interval in atomic hydrogen was measured using Ramsey spectroscopy with a thermal beam cooled to cryogenic temperatures. The measured value is 177 556 838.87(85) Hz, which represents the most precise determination of this interval to date. The 1S_{1/2} hyperfine interval f(1S_{1/2}) and the 2S_{1/2} hyperfine interval f(2S_{1/2}) can be combined to give the quantity D_{21}=8f(2S_{1/2})-f(1S_{1/2}), which mostly eliminates uncertainty due to nuclear structure effects and is well described by bound-state quantum electrodynamics. Using the value of f(2S_{1/2}) from this work gives a value of D_{21}^{expt}=48 959.2(6.8) Hz, which is in agreement with the theoretical value of D_{21}^{Theory}=48 954.1(2.3) Hz.

2.
Dev Psychopathol ; 32(3): 1069-1085, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31489833

RESUMEN

Moral reasoning and decision making help guide behavior and facilitate interpersonal relationships. Accounts of morality that position commonsense psychology as the foundation of moral development, (i.e., rationalist theories) have dominated research in morality in autism spectrum disorder (ASD). Given the well-documented differences in commonsense psychology among autistic individuals, researchers have investigated whether the development and execution of moral judgement and reasoning differs in this population compared with neurotypical individuals. In light of the diverse findings of investigations of moral development and reasoning in ASD, a summation and critical evaluation of the literature could help make sense of what is known about this important social-cognitive skill in ASD. To that end, we conducted a systematic review of the literature investigating moral decision making among autistic children and adults. Our search identified 29 studies. In this review, we synthesize the research in the area and provide suggestions for future research. Such research could include the application of an alternative theoretical framework to studying morality in autism spectrum disorder that does not assume a deficits-based perspective.


Asunto(s)
Trastorno del Espectro Autista , Adulto , Niño , Humanos , Relaciones Interpersonales , Juicio , Principios Morales , Conducta Social
3.
Neurobiol Learn Mem ; 162: 36-46, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31125611

RESUMEN

In order to optimize outcomes in the face of uncertainty, one must recall past experiences and extrapolate to the future by assigning values to different choice outcomes. This behavior requires an interplay between memory and reward valuation, necessitating communication across many brain regions. At the anatomical nexus of this interplay is the perirhinal cortex (PRC). The PRC is densely connected to the amygdala and orbital frontal cortex, regions that have been implicated in reward-based decision making, as well as the hippocampus. Thus, the PRC could serve as a hub for integrating memory, reward, and prediction. The PRC's role in value-based decision making, however, has not been empirically examined. Therefore, we tested the role of the PRC in a spatial delay discounting task, which allows rats to choose between a 1-s delay for a small food reward and a variable delay for a large food reward, with the delay to the large reward increasing after choice of each large reward and decreasing after each small reward. The rat can therefore adjust the delay by consecutively choosing the same reward or stabilize the delay by alternating between sides. The latter has been shown to occur once the 'temporal cost' of the large reward is established and is a decision-making process termed 'exploitation'. When the PRC was bilaterally inactivated with the GABA(A) agonist muscimol, rats spent fewer trials successfully exploiting to maintain a fixed delay compared to the vehicle control condition. Moreover, PRC inactivation resulted in an increased number of vicarious trial and error (VTE) events at the choice point, where rats had to decide between the two rewards. These behavioral patterns suggest that the PRC is critical for maintaining stability in linking a choice to a reward outcome in the face of a variable cost.


Asunto(s)
Conducta de Elección/fisiología , Descuento por Demora/fisiología , Corteza Perirrinal/fisiología , Conducta Espacial/fisiología , Animales , Conducta de Elección/efectos de los fármacos , Descuento por Demora/efectos de los fármacos , Agonistas de Receptores de GABA-A/farmacología , Masculino , Muscimol/farmacología , Corteza Perirrinal/efectos de los fármacos , Ratas , Conducta Espacial/efectos de los fármacos , Factores de Tiempo
4.
Br J Anaesth ; 119(3): 524-531, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28969320

RESUMEN

BACKGROUND: Retrospective clinical studies suggest there is a risk for neurodevelopmental impairment following early childhood exposure to anaesthesia. In the developing animal brain, including those of non-human primates (NHPs), anaesthetics induce apoptotic cell death. We previously reported that a 5 h isoflurane (ISO) exposure in infant NHPs increases apoptosis 13-fold compared with control animals. However, the majority of paediatric surgeries requiring anaesthesia are of shorter durations. We examined whether 3 h ISO exposure similarly increases neuroapoptosis in the NHP developing brain. METHODS: Six-day-old NHP infants ( Macaca mulatta ) were exposed to 3 h of a surgical plane of ISO ( n =6) or to room air ( n =5). Following exposure, NHP brains were screened for neuronal and oligodendrocyte apoptosis using activated caspase-3 immunolabelling and unbiased stereology. RESULTS: ISO treatment increased apoptosis (neurones + oligodendrocyte) to greater than four times that in the control group [mean density of apoptotic profiles: 57 (SD 22) mm -3 vs 14 (SD 5.2) mm -3 , respectively]. Oligodendrocyte apoptosis was evenly distributed throughout the white matter whereas neuroapoptosis occurred primarily in the cortex (all regions), caudate, putamen and thalamus. CONCLUSIONS: A 3 h exposure to ISO is sufficient to induce widespread neurotoxicity in the developing primate brain. These results are relevant for clinical medicine, as many surgical and diagnostic procedures in children require anaesthesia durations similar to those modelled here. Further research is necessary to identify long-term neurobehavioural consequences of 3 h ISO exposure.


Asunto(s)
Anestésicos por Inhalación/efectos adversos , Apoptosis/efectos de los fármacos , Encéfalo/efectos de los fármacos , Isoflurano/efectos adversos , Síndromes de Neurotoxicidad/etiología , Animales , Animales Recién Nacidos , Encéfalo/patología , Modelos Animales de Enfermedad , Femenino , Macaca mulatta , Masculino , Síndromes de Neurotoxicidad/patología , Tiempo
5.
Osteoporos Int ; 27(7): 2271-2279, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26902092

RESUMEN

UNLABELLED: Daily consumption of 50 g of dried plum (equivalent to 5-6 dried plums) for 6 months may be as effective as 100 g of dried plum in preventing bone loss in older, osteopenic postmenopausal women. To some extent, these results may be attributed to the inhibition of bone resorption with the concurrent maintenance of bone formation. INTRODUCTION: The objective of our current study was to examine the possible dose-dependent effects of dried plum in preventing bone loss in older osteopenic postmenopausal women. METHODS: Forty-eight osteopenic women (65-79 years old) were randomly assigned into one of three treatment groups for 6 months: (1) 50 g of dried plum; (2) 100 g of dried plum; and (3) control. Total body, hip, and lumbar bone mineral density (BMD) were evaluated at baseline and 6 months using dual-energy X-ray absorptiometry. Blood biomarkers including bone-specific alkaline phosphatase (BAP), tartrate-resistant acid phosphatase (TRAP-5b), high-sensitivity C-reactive protein (hs-CRP), insulin-like growth factor-1 (IGF-1), and sclerostin were measured at baseline, 3 months, and 6 months. Osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), calcium, phosphorous, and vitamin D were measured at baseline and 6 months. RESULTS: Both doses of dried plum were able to prevent the loss of total body BMD compared with that of the control group (P < 0.05). TRAP-5b, a marker of bone resorption, decreased at 3 months and this was sustained at 6 months in both 50 and 100 g dried plum groups (P < 0.01 and P < 0.04, respectively). Although there were no significant changes in BAP for either of the dried plum groups, the BAP/TRAP-5b ratio was significantly (P < 0.05) greater at 6 months in both dried plum groups whereas there were no changes in the control group. CONCLUSIONS: These results confirm the ability of dried plum to prevent the loss of total body BMD in older osteopenic postmenopausal women and suggest that a lower dose of dried plum (i.e., 50 g) may be as effective as 100 g of dried plum in preventing bone loss in older, osteopenic postmenopausal women. This may be due, in part, to the ability of dried plums to inhibit bone resorption. This clinical trial was registered at ClinicalTrials.gov: NCT02325895 .


Asunto(s)
Densidad Ósea , Frutas , Osteoporosis Posmenopáusica/prevención & control , Prunus domestica , Anciano , Biomarcadores/análisis , Huesos/patología , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/dietoterapia , Posmenopausia
6.
J R Army Med Corps ; 162(5): 361-365, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26607859

RESUMEN

INTRODUCTION: For the purposes of patient safety, audit and research, the electronic patient record (EPR) must be accurate and searchable. No evaluation of the accuracy of EPRs compared with paper records has been made. Furthermore, the use of Read codes is known to be heterogeneous. This study was designed to evaluate the EPR used by the UK Armed Forces. METHODS: A cross-sectional study reviewing the paper records and EPRs of 50 consecutive soldiers posted to a British Army Training Regiment. RESULTS: There was a pre-enlistment summary in only 38% of the paper notes, although 24% had some primary care records from prior to enlistment. There were 357 entries that should have been transferred to the EPR. Of these, only 190 (53.2%) were transferred with appropriate Read codes, while only 24% of patients reviewed had all their entries appropriately Read coded. There were 168 secondary care letters discovered with 122 (72.6%) generically Read coded and 46 (27.4%) using an appropriate Read code. Of those letters with more than one potential Read code, 34 (73.9%) were coded using all appropriate Read codes. Several incidental errors in the medical records were also discovered with significant patient safety implications. CONCLUSIONS: The historical paper-based medical record was found to have many data missing. The transfer of these paper records to the EPR has been inaccurate with many records not transferred or transferred ineffectively. These findings have an impact on patient safety, audit and data security and should trigger a review of how the Armed Forces manage their primary care records.


Asunto(s)
Registros Electrónicos de Salud/normas , Medicina Militar , Personal Militar , Atención Primaria de Salud , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reino Unido , Adulto Joven
7.
Health Promot Int ; 30(1): 126-39, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25252597

RESUMEN

Engaging in outdoor nature-based spaces has significant positive physiological and psychological health benefits. Although the integration of nature into indoor spaces is rarely considered a health-promoting tool, it may be an effective method for increasing nature engagement in a largely urbanized world. This paper presents an overview of indoor nature exposure (INE) by summarizing the current evidence of INE through the use of a scoping methodology. Results show that INE can be a health-promoting tool through the interaction of nature-based stimuli and individual characteristics (e.g. gender, age). Moreover, the results of the current literature need to be interpreted with consideration to methodological issues, such as the lack of participant characteristics, the issue of exposure realism and little qualitative data to highlight individual experiences. The scoping review process allowed for the summation of results and for a framework to be created in order to better understand how INE is facilitated.


Asunto(s)
Flores , Promoción de la Salud/métodos , Salud Mental , Plantas , Emociones , Ambiente , Humanos , Naturaleza
8.
J Econ Entomol ; 107(1): 154-60, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24665697

RESUMEN

Phlyctinus callosus (Boheman) (Coleoptera: Curculionidae) is a pest of major phytosanitary concern for some of South Africa's biggest export markets such as the United States and Europe because this pest does not occur there. At present, fumigation with methyl bromide is the only postharvest disinfestation treatment against this pest; therefore, sustainable alternatives are needed. One such alternative is irradiation treatment of whole pallets of packed fruit to sterilize insects that may be present within the cartons. Wild adult P. callosus weevils were treated with 5, 10, 20, 40, and 80 Gy of gamma-irradiation and then cross mated to breed with either treated or nontreated adults of the opposite sex. Fecundity and fertility were monitored and recorded. Trials were conducted during the 2009-2010 and 2010-2011 fruit harvesting seasons. The results from both seasons indicated that irradiation did not affect fecundity but fertility was significantly affected, decreasing as irradiation doses increased. Egg hatch was zero for mating crosses that involved females weevils treated with a dose of 80 Gy gamma-irradiation. Probit analysis indicated that in the first season, the estimated LD95 for crosses involving treated males and treated females was 30 Gy, while in the second season it was 49.5 Gy. Respective estimated LD99S were 47.9 and 169.4 Gy. Ultimately, a dose lower than the current generic dose of 400 Gy, approved for irradiation disinfestation treatments, would control P. callosus should they occur in packed export fruit.


Asunto(s)
Rayos gamma , Gorgojos/efectos de la radiación , Animales , Femenino , Masculino , Dosis de Radiación , Reproducción/efectos de la radiación
9.
J Acoust Soc Am ; 131(5): 3802-13, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22559356

RESUMEN

Recent published results in inverse scattering generally show the difficulty in dealing with moderate to high contrast inhomogeneities when employing linearized or iteratively linearized algorithms (e.g., distorted Born iterative method). This paper presents a fully nonlinear algorithm utilizing full wave field data, that results in ultrasound computed tomographic images from a laboratory breast scanner, and shows several such unique images from volunteer subjects. The forward problem, data collection process and inverse scattering algorithm used are discussed. A functional that represents the "best fit" between predicted and measured data is minimized, and therefore requires a very fast forward problem solver, Jacobian calculation, and gradient estimation, all of which are described. The data collection device is described. The algorithm and device yield quantitative estimates of human breast tissue in vivo. Several high resolution images, measuring ∼150 by 150 wavelengths, obtained from the 2D inverse scattering algorithms, using data collected from a first prototype, are shown and discussed. The quantitative values are compared with previous published work.


Asunto(s)
Algoritmos , Enfermedades de la Mama/diagnóstico por imagen , Ultrasonografía Mamaria/métodos , Anciano , Quiste Mamario/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/diagnóstico por imagen , Diseño de Equipo , Femenino , Fibroadenoma/diagnóstico por imagen , Humanos , Fantasmas de Imagen , Dispersión de Radiación , Sonido , Transductores , Ultrasonografía Mamaria/instrumentación
10.
Biochim Biophys Acta ; 1798(7): 1427-35, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20230780

RESUMEN

Liquid-ordered (Lo) and liquid-disordered (Ld) phase coexistence has been suggested to partition the plasma membrane of biological cells into lateral compartments, allowing for enrichment or depletion of functionally relevant molecules. This dynamic partitioning might be involved in fine-tuning cellular signaling fidelity through coupling to the plasma membrane protein and lipid composition. In earlier work, giant plasma membrane vesicles, obtained by chemically induced blebbing from cultured cells, were observed to reversibly phase segregate at temperatures significantly below 37 degrees C. In this contribution, we compare the temperature dependence of fluid phase segregation in HeLa and rat basophilic leukemia (RBL) cells. We find an essentially monotonic temperature dependence of the number of phase-separated vesicles in both cell types. We also observe a strikingly broad distribution of phase transition temperatures in both cell types. The binding of peripheral proteins, such as cholera toxin subunit B (CTB), as well as Annexin V, is observed to modulate phase transition temperatures, indicating that peripheral protein binding may be a regulator for lateral heterogeneity in vivo. The partitioning of numerous signal protein anchors and full length proteins is investigated. We find Lo phase partitioning for several proteins assumed in the literature to be membrane raft associated, but observe deviations from this expectation for other proteins, including caveolin-1.


Asunto(s)
Anexina A5/química , Caveolina 1/química , Membrana Celular/química , Toxina del Cólera/química , Lípidos de la Membrana/química , Transición de Fase , Animales , Anexina A5/metabolismo , Caveolina 1/metabolismo , Membrana Celular/metabolismo , Toxina del Cólera/metabolismo , Células HeLa , Calor , Humanos , Lípidos de la Membrana/metabolismo , Ratas
11.
J Econ Entomol ; 104(2): 398-404, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21510185

RESUMEN

Nonchemical, environmentally friendly quarantine treatments are preferred for use in postharvest control of insect pests. Combined high temperature and controlled atmosphere quarantine treatments for phytosanitary fruit pests Macchiademus diplopterus (Distant) (Hemiptera: Lygaeidae) and Phlyctinus callosus (Schoenherr) (Coleoptera: Curculionidae) were investigated to determine the potential of such treatments for quarantine security. Field-collected, aestivating M. diplopterus adults and P. callosus adults were treated using a controlled atmosphere waterbath system. This system simulates the controlled atmosphere temperature treatment system (CATTS) used to control a number of phytosanitary pests in the United States and allows for a rapid assessment of pest response to treatment. Insects were treated under regular air conditions and a controlled atmosphere of 1% oxygen, 15% carbon dioxide in nitrogen, at two ramping heat rates, 12 and 24 degrees C/h. Treatment of both species was more effective under both heating rates when the controlled atmosphere condition was applied. Under these conditions of controlled atmospheres, mortality of P. callosus was greater when the faster heating rate was used, but the opposite was true for M. diplopterus. This could be due to the physiological condition of aestivation contributing to metabolic arrest in response to the stresses being applied during treatment. Results indicate that the potential for the development of CATTS treatments for these phytosanitary pests, particularly P. callosus, is promising.


Asunto(s)
Ambiente Controlado , Frutas/parasitología , Heterópteros , Control de Insectos , Gorgojos , Anaerobiosis , Animales , Dióxido de Carbono , Parasitología de Alimentos , Calor
12.
J Exp Med ; 182(6): 1815-23, 1995 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7500027

RESUMEN

To explore the mechanism(s) by which the Syk protein tyrosine kinase participates in B cell antigen receptor (BCR) signaling, we have studied the function of various Syk mutants in B cells made Syk deficient by homologous recombination knockout. Both Syk SH2 domains were required for BCR-mediated Syk and phospholipase C (PLC)-gamma 2 phosphorylation, inositol 1,4,5-triphosphate release, and Ca2+ mobilization. A possible explanation for this requirement was provided by findings that recruitment of Syk to tyrosine-phosphorylated immunoglobulin (Ig) alpha and Ig beta requires both Syk SH2 domains. A Syk mutant in which the putative autophosphorylation site (Y518/Y519) of Syk was changed to phenylalanine was also defective in signal transduction; however, this mutation did not affect recruitment to the phosphorylated immunoreceptor family tyrosine-based activation motifs (ITAMs). These findings not only confirm that both SH2 domains are necessary for Syk binding to tyrosine-phosphorylated Ig alpha and Ig beta but indicate that this binding is necessary for Syk (Y518/519) phosphorylation after BCR ligation. This sequence of events is apparently required for coupling the BCR to most cellular protein tyrosine phosphorylation, to the phosphorylation and activation of PLC-gamma 2, and to Ca2+ mobilization.


Asunto(s)
Linfocitos B/inmunología , Precursores Enzimáticos/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Secuencia de Aminoácidos , Calcio/metabolismo , Células Cultivadas , Inositol 1,4,5-Trifosfato/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Péptidos/química , Fosforilación , Transducción de Señal , Relación Estructura-Actividad , Quinasa Syk , Dominios Homologos src
13.
Int J STD AIDS ; 21(1): 39-45, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20029064

RESUMEN

Sexual health services in primary care, known in the UK as local enhanced services in sexual health (LESSH), aim to increase access to sexually transmitted infection (STI) screening and treatment. Little is known about the characteristics, quality or public health impact of these services. We identified national standards for service provision, and evaluated LESSH against them using a structure, process and outcome approach. Clinical structure and process standards were generally well met, with the exception of partner notification provision. However, public health and outcome measures were largely unascertainable and often undefined in the standards. If the primary care STI services are to deliver public health benefit, improved outcome measures and data collection are required.


Asunto(s)
Servicios de Salud Comunitaria/normas , Beneficios del Seguro , Atención Primaria de Salud/normas , Garantía de la Calidad de Atención de Salud/normas , Enfermedades de Transmisión Sexual , Humanos , Salud Pública/normas , Parejas Sexuales , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/terapia , Reino Unido/epidemiología
14.
J Econ Entomol ; 103(2): 265-71, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20429437

RESUMEN

Controlled atmosphere/temperature treatment system (CATTS) is an environmentally friendly postharvest mitigation treatment that uses high temperature forced-air combined with a low oxygen and high carbon dioxide atmosphere to control quarantine pests. The development of CATTS treatments is expensive and time-consuming. For a more rapid assessment of different species and life stages' tolerances to heated controlled atmospheres, the controlled atmosphere water bath (CAWB) system can be used to help advance the development of CATTS treatments for pests. The CAWB system was used to test the response of eggs and larval stages of Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae). Eggs and larvae at different developmental stages were treated under regular air and a modified controlled atmosphere of 1% O2 and 15% CO2, at two ramping heat rates: 12 and 24 degrees C/h. Typically the faster heat rate and modified atmosphere reduced treatment times required to control the different life stages. T. leucotreta larvae were more tolerant of the treatments than eggs. The most tolerant life stage was the fourth instar. Effective treatments against the most tolerant life stage determined by the CAWB system can now be used to develop CATTS technology against T. leucotreta. Further research will focus on developing CATS treatments using infested fruit to determine effective treatments that maintain fruit quality.


Asunto(s)
Calor , Control de Insectos/métodos , Mariposas Nocturnas/fisiología , Animales , Atmósfera
15.
Benef Microbes ; 11(7): 621-630, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-33161737

RESUMEN

Cardiovascular disease (CVD) is the leading cause of death in the US and worldwide. By 2030 it is anticipated that CVD will claim the lives of more than 24 million people. Throughout the last decade, researchers have investigated the role of the gut microbiota in the development of CVD. Evidence exists for a positive correlation between Bifidobacterium and vascular function, glucose tolerance, and reduced systemic inflammation. Another probiotic species, Bacillus subtilis, has also been found to reduce cholesterol levels in human and animal models. In light of these data, we examined various measures of cardiovascular health after consumption of Bifidobacterium animalis subsp. lactis strain BL04, with and without a cocktail of Escherichia coli-targeting bacteriophages (marketed as PreforPro), Bacillus subtilis strain DE111 or a maltodextrin-based placebo in a healthy human population. In a randomised, double-blind, placebo-controlled 4-week intervention conducted in individuals 18 to 65 years of age with a body mass index of 20 to 34.9, we saw no significant changes in measured CVD parameters among individuals consuming B. lactis with or without bacteriophages. However, B. subtilis supplementation resulted in a significant reduction in total cholesterol relative to baseline measures (-8 mg/dl; P=0.04, confidence interval (CI): -13.40, -0.19), as well as non-high-density lipoprotein-cholesterol (-11 mg/dl; P=0.01, CI: -12.43, -2.07). In addition we observed trending improvements in endothelial function (P=0.05, CI: -0.003, 0.370) and in low-density lipoprotein-cholesterol (P=0.06, CI:-12.29, 0.2864). Strikingly, these effects were seen in a largely healthy population. These data suggest that B. subtilis supplementation may be beneficial for improving risk factors associated with CVD. Further studies in populations of older adults or those with dyslipidaemia and endothelial dysfunction is warranted.


Asunto(s)
Bacillus subtilis/fisiología , Lípidos/sangre , Probióticos/administración & dosificación , Adolescente , Adulto , Anciano , Colesterol/sangre , LDL-Colesterol/sangre , Método Doble Ciego , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Probióticos/farmacología , Adulto Joven
16.
Science ; 191(4222): 77-9, 1976 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-1856

RESUMEN

Infrared spectra of time- and size-classified atmospheric particulate samples collected with a inertial impactor reveal the presence of acid sulfate in the submicrometer-sized fraction. Although the degree of acidity is highly variable with time, the acidic nature of the particles is observed at all times of the day and may persist for several days in urban areas.


Asunto(s)
Contaminantes Atmosféricos/análisis , Sulfatos/análisis , Aerosoles , Chicago , Concentración de Iones de Hidrógeno , Missouri
17.
Science ; 283(5404): 963-5, 1999 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-9974384

RESUMEN

Ordered mesoporous polymers have been prepared by replication of colloidal crystals made from silica spheres 35 nanometers in diameter. The pores in the colloidal crystals were filled with divinylbenzene (DVB), ethyleneglycol dimethacrylate (EDMA), or a mixture of the two. Polymerization and subsequent dissolution of the silica template leaves a polycrystalline network of interconnected pores. When mixtures of DVB and EDMA are used, the pore size of the polymer replicas can be varied continuously between 35 and 15 nanometers because the polymer shrinks when the silica template is removed.


Asunto(s)
Metacrilatos/química , Polímeros/química , Dióxido de Silicio/química , Compuestos de Vinilo/química , Coloides , Cristalización , Microscopía Electrónica
18.
Science ; 248(4957): 854-7, 1990 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-2111579

RESUMEN

An ongoing controversy concerns the cellular distribution of the differentially spliced forms of the amyloid protein precursor (APP) mRNAs and changes in prevalence of these transcripts during Alzheimer's disease. In situ hybridization on serial sections was used to prove that most hippocampal pyramidal neurons contain both APP-751 and APP-695 mRNA species. The APP-751/APP-695 mRNA ratio is generally increased during Alzheimer's disease, as shown by RNA gel blot analysis. Moreover, there was a strong linear relation between the increase in APP-751/APP-695 mRNA ratio in pyramidal neurons and the density of senile plaques within the hippocampus and entorhinal cortex. Thus, the increase in APP-751/APP-695 mRNA provides a molecular marker for regional variations in plaque density between individuals diagnosed with Alzheimer's disease by the commonly used composite criteria.


Asunto(s)
Enfermedad de Alzheimer/patología , Amiloide/genética , Encéfalo/patología , Precursores de Proteínas/genética , Empalme del ARN , ARN Mensajero/metabolismo , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide , Encéfalo/metabolismo , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Hipocampo/metabolismo , Humanos , Neuronas/metabolismo , Neuronas/patología , Hibridación de Ácido Nucleico , Sondas ARN
19.
Science ; 258(5079): 123-6, 1992 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-1439759

RESUMEN

The B cell antigen receptor complex is a hetero-oligomeric structure composed of antigen binding, membrane immunoglobulin, and transducer-transporter substructures. The transducer-transporter substructure is composed of disulfide-linked dimers of immunoglobulin (Ig)-alpha and Ig-beta/gamma subunits that are products of the mb-1(alpha) and B29 (beta/gamma) genes. Although the receptor complex associates with Src family kinases that are activated after receptor ligation, the site of interaction of these and other cytoplasmic effector molecules with receptor subunits is unknown. The cytoplasmic tails of Ig-alpha and Ig-beta chains were found to associate with distinct sets of effector molecules. The Ig-alpha chain cytoplasmic domain bound to the Src family kinases Lyn and Fyn, phosphatidylinositol-3 kinase (PI-3 kinase), and an unidentified 38-kilodalton phosphoprotein; the cytoplasmic tail of Ig-beta bound PI-3 kinase and unidentified 40- and 42-kilodalton phosphoproteins. Binding activity was found to occur within a 26-amino acid sequence of Ig-alpha and Ig-beta that contains a motif [(Asp or Glu)-(any amino acid)7-(Asp or Glu)-Tyr-(any amino acid)3-Leu-(any amino acid)7-Tyr-(any amino acid)2-(Leu or Ile)] previously implicated in signal transduction via other receptors including the Fc epsilon receptor I and the T cell antigen receptor. These findings indicate that the subunits act independently to activate distinct second messenger pathways.


Asunto(s)
Antígenos CD/metabolismo , Citoplasma/metabolismo , Inmunoglobulina M/metabolismo , Receptores de Antígenos de Linfocitos B/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Antígenos CD79 , Electroforesis en Gel de Poliacrilamida , Genes src , Humanos , Immunoblotting , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Proteínas Quinasas/metabolismo , Proteínas Recombinantes de Fusión , Transducción de Señal/fisiología
20.
Science ; 216(4552): 1313-5, 1982 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-7079763

RESUMEN

Nuclear magnetic resonance imaging was used to determine quantitatively the water distribution of saline-filled and normal rat lungs in both isolated lung and in situ preparations. Regional lung edema was easily detected. Studies of an isolated lung fragment indicate an accuracy of better than 1 percent and images of H2O/D2O phantoms indicate an average error of 2.7 percent.


Asunto(s)
Agua Corporal/análisis , Pulmón/análisis , Animales , Espectroscopía de Resonancia Magnética , Edema Pulmonar/diagnóstico , Ratas
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