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1.
J Food Sci ; 78(7): S1057-62, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23772800

RESUMEN

The objective of this study was to determine the percentage oxygen consumption of fresh, respiring ready-to-eat (RTE) mixed leaf salad products (Iceberg salad leaf, Caesar salad leaf, and Italian salad leaf). These were held under different modified atmosphere packaging (MAP) conditions (5% O2 , 5% CO2 , 90% N2 (MAPC-commercial control), 21% O2 , 5% CO2 , 74% N2 (MAP 1), 45% O2 , 5% CO2 , 50% N2 (MAP 2), and 60% O2 , 5% CO2 , 35% N2 (MAP 3)) and 4 °C for up to 10 d. The quality and shelf-life stability of all packaged salad products were evaluated using sensory, physiochemical, and microbial assessment. Oxygen levels in all MAP packs were measured on each day of analysis using optical oxygen sensors allowing for nondestructive assessment of packs. Analysis showed that with the exception of control packs, oxygen levels for all MAP treatments decreased by approximately 10% after 7 d of storage. Oxygen levels in control packs were depleted after 7 d of storage. This appears to have had no detrimental effect on either the sensory quality or shelf-life stability of any of the salad products investigated. Additionally, the presence of higher levels of oxygen in modified atmosphere packs did not significantly improve product quality or shelf-life stability; however, these additional levels of oxygen were freely available to fresh respiring produce if required. This study shows that the application of optical sensors in MAP packs was successful in nondestructively monitoring oxygen level, or changes in oxygen level, during refrigerated storage of RTE salad products.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos/métodos , Almacenamiento de Alimentos/métodos , Oxígeno/análisis , Verduras/microbiología , Recuento de Colonia Microbiana , Seguridad de Productos para el Consumidor , Microbiología de Alimentos , Humanos , Viabilidad Microbiana , Control de Calidad , Gusto , Vacio
2.
J Food Prot ; 74(5): 776-82, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21549048

RESUMEN

A simple, miniaturized, and automated screening assay for the determination of total aerobic viable counts in fish samples is presented here. Fish tissue homogenates were prepared in peptone buffered water medium, according to standard method, and aliquots were dispensed into wells of a 96-well plate with the phosphorescent, oxygen-sensing probe GreenLight. Sample wells were covered with mineral oil (barrier for ambient oxygen), and the plate was monitored on a standard fluorescent reader at 30°C. The samples produced characteristic profiles, with a sharp increase in fluorescence above the baseline level at a certain threshold time, which could be correlated with initial microbial load. Five different fish species were analyzed: salmon, cod, plaice, mackerel, and whiting. Using a conventional agar plating method, the relationship between the threshold time and total aerobic viable counts load (in CFU per gram) was established, calibration curve generated, and the test was validated with 169 unknown fish samples. It showed a dynamic range of 10(4) to 10(7) CFU/g, accuracy of ± 1 log(CFU/g), assay time of 2 to 12 h (depending on the level of contamination), ruggedness with respect to the key assay parameters, simplicity (three pipetting steps, no serial dilutions), real-time data output, high sample throughput, and automation. With this test, quality of fish samples, CFU-per-gram levels, and their respective time profiles were determined.


Asunto(s)
Bacterias Aerobias/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Recuento de Colonia Microbiana/métodos , Alimentos Marinos/microbiología , Espectrometría de Fluorescencia/métodos , Animales , Peces , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Humanos , Oxígeno/metabolismo
3.
Z Kardiol ; 93(5): 388-97, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15160274

RESUMEN

Human heart-type fatty acid-binding protein (FABP) has a high potential as an early marker for myocardial infarction (MI) being more specific than myoglobin. FABP is a low molecular mass cytoplasmic protein (15 kDa) that is released early after the onset of ischemia and it may be useful for rapid confirmation or exclusion of acute myocardial infarction (AMI). Immunochemically assayed FABP, cardiac troponin I (cTnI) and enzymatically assayed creatine phosphokinase (CPK) were determined serially in plasma and serum samples from 218 patients presenting with chest pain and suspected MI. In the 94 patients with confirmed MI, FABP rose to a maximum level (577.6 +/- 43.8 microg/L) 3 hours after the onset of symptoms and returned to normal within 30 hours. The FABP level peaked 7-9 hours earlier than CPK (2288 +/- 131 U/L) and cTnI (357.1 +/- 23.9 microg/L). CPK took 50-70 hours to return to normal level and cTnI returned to normal level over 70 hours. The areas under the receiver operating characteristic (ROC) curves for FABP were calculated as 0.871 at admission and 0.995 one hour after admission, whereas for CPK the areas were 0.711 and 0.856 and for cTnI the areas were 0.677 and 0.845, indicating that the FABP test gave a better diagnostic classification at the early stage being reached by cTnI (0.995) only 8 hours after admission. For FABP, both sensitivity and negative predictive value (NPV) increased quickly to 100% for samples monitored just one hour after admission. By using only two samples, one at admission and one 1 hour post admission, sequential FABP monitoring can reliably diagnose AMI patients 1 hour after admission and 100% of non-AMI patients can be excluded with no false negative results. The late markers cTnI and CPK have the similar diagnostic performance only 7 hours later. Thus measurement of FABP in plasma or serum allows the earliest immunochemical confirmation or exclusion of AMI.


Asunto(s)
Proteínas Portadoras/sangre , Creatina Quinasa/sangre , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Troponina I/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Proteínas de Unión a Ácidos Grasos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
4.
Radiologe ; 43(7): 558-61, 2003 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-12955219

RESUMEN

Currently, different cerebral neuroimaging methods are being applied to varying questions in the diagnosis of dementia. In patients with manifest Alzheimer's disease a reduction of cortical perfusion and metabolism in temporal and temporoparietal regions has been demonstrated when compared to healthy controls on a diversity of memory tasks. Since differing levels of performance and varying degrees of cortical atrophy may influence functional results considerably, an understanding of the processes associated with normal ageing is perceived as prerequisite for studies applying functional neuroimaging. The integration of knowledge concerning neuropsychological and neurobiological alterations associated with healthy ageing allows hypotheses for the differentiation of pathological ageing processes to be phrased. In this connection non-invasive methods such as fMRI and ASL are of increasing importance.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Demencia/diagnóstico , Imagen por Resonancia Magnética , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Encéfalo/metabolismo , Circulación Cerebrovascular , Ensayos Clínicos como Asunto , Demencia/metabolismo , Demencia/fisiopatología , Diagnóstico Diferencial , Glucosa/metabolismo , Humanos , Imagen por Resonancia Magnética/métodos , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/etiología , Persona de Mediana Edad , Factores de Riesgo , Sensibilidad y Especificidad , Factores de Tiempo
6.
Psychiatry Res ; 108(2): 133-40, 2001 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-11738547

RESUMEN

In a case of Fahr's disease with frontal lobe type dementia and hyperkinetic-hypotone syndrome, functional changes were investigated using positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) as a tracer. Computed tomography showed bilateral calcifications in the putamen and globus pallidus consistent with the diagnosis of Fahr's disease and a frontally pronounced brain atrophy. In contrast, reduced glucose uptake in PET was not only confined to the areas mentioned above, but extended to the temporal and parietal cortices, bilaterally. These functional changes corresponded to the neuropsychological deficits observed, i.e. disturbed selective attention and cognitive flexibility, verbal perseverations, and declarative memory deficits. It is suggested that functional changes may precede cerebral atrophy in Fahr's disease and may reflect deficits in functional circuits, which involve both the basal ganglia and the frontal, parietal, and temporal lobes.


Asunto(s)
Enfermedades de los Ganglios Basales/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Demencia/diagnóstico por imagen , Metabolismo Energético/fisiología , Pruebas Neuropsicológicas , Tomografía Computarizada de Emisión , Adulto , Atrofia , Enfermedades de los Ganglios Basales/psicología , Mapeo Encefálico , Calcinosis/psicología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Demencia/psicología , Femenino , Humanos , Síndrome
7.
Phys Rev Lett ; 87(21): 217401, 2001 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-11736377

RESUMEN

Positron beam timing spectroscopy has been used to investigate positron diffusion in hydrogenated amorphous silicon between 85 and 350 K. The diffusivity is determined from both the contribution of the surface, where the positrons have a different characteristic annihilation rate, and its effect on the shape of the bulk annihilation rate distribution. We observe a single positron state with a temperature independent lifetime of 322 ps. From the temperature dependence of the positron diffusion we show that this is a localized state and present the first ever direct observation of hopping diffusion of positrons in solids. The migration enthalpy for positrons in this state is found to be 17.7(3) meV.

8.
J Am Acad Child Adolesc Psychiatry ; 40(6): 719-28, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11392351

RESUMEN

OBJECTIVE: The authors conducted a descriptive, archival study of adolescent (< or =19 years of age) mass murderers-subjects who intentionally killed three or more victims in one event-to identify demographic, clinical, and forensic characteristics. METHOD: A nonrandom sample of convenience of adolescent mass murderers was utilized. RESULTS: Thirty-four subjects, acting alone or in pairs, committed 27 mass murders between 1958 and 1999. The sample consisted of males with a median age of 17. A majority were described as "loners" and abused alcohol or drugs; almost half were bullied by others, preoccupied with violent fantasy, and violent by history. Although 23% had a documented psychiatric history, only 6% were judged to have been psychotic at the time of the mass murder. Depressive symptoms and historical antisocial behaviors were predominant. There was a precipitating event in most cases--usually a perceived failure in love or school--and most subjects made threatening statements regarding the mass murder to third parties. The majority of the sample clustered into three types: the family annihilator, the classroom avenger, and the criminal opportunist. CONCLUSIONS: The adolescent mass murderer is often predatorily rather than affectively violent and typically does not show any sudden or highly emotional warning signs. Although the act of mass murder is virtually impossible to predict because of its extremely low frequency, certain clinical and forensic findings can alert the clinician to the need for further, intensified primary care, including family, school, community, law enforcement, and mental health intervention.


Asunto(s)
Homicidio/estadística & datos numéricos , Delincuencia Juvenil/psicología , Delincuencia Juvenil/estadística & datos numéricos , Adolescente , Conducta del Adolescente/psicología , Adulto , Niño , Humanos , Soledad/psicología , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología
9.
J Forensic Sci ; 46(3): 586-92, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11372993

RESUMEN

Combined homicide-suicides have been classified based on the psychopathology of the perpetrator and the nature of the relationship between perpetrator and victim(s). To further understand the nature of this tragic phenomenon and to test the validity and practicality of a previously suggested classification system, investigators systematically collected data on all combined homicide-suicide events that occurred in Galveston County, Texas over a continuous 18-year period (n = 20). The most common psychopathological finding for perpetrators was high serum alcohol levels that suggested intoxication. Most combined homicide-suicides fell into one of the relational categories and most of these, as predicted, were of the consortial type, possessive subtype. As expected, due to the small sample size, the less common types of combined homicide-suicide were not represented in this sample.


Asunto(s)
Homicidio/estadística & datos numéricos , Suicidio/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Intoxicación Alcohólica , Niño , Femenino , Psiquiatría Forense , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Texas/epidemiología
11.
Acta Crystallogr C ; 56 ( Pt 10): 1225-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11025305

RESUMEN

The crystal structure of the title compound contains four 2, 4-diamino-5-methyl-6-[(3,4,5-trimethoxyanilino)methyl]quinazoline molecules, two dimethyl sulfoxide molecules and three water molecules in the asymmetric unit, i.e. 4C(19)H(23)N(5)O(3).-2C(2)H(6)OS.3H(2)O. All four quinazoline molecules adopt trans,-gauche conformations. An extensive hydrogen-bond network involving N. N base-pairing interactions, as well as the dimethyl sulfoxide and water molecules, stabilizes the crystal structure.


Asunto(s)
Antagonistas del Ácido Fólico/química , Tetrahidrofolato Deshidrogenasa/metabolismo , Trimetrexato/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Lacticaseibacillus casei/enzimología , Modelos Moleculares , Conformación Molecular , Unión Proteica
12.
Acta Crystallogr C ; 56 ( Pt 8): 1048-9, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10944325

RESUMEN

In the title compound, dimethyl(¿5-[2-(1-methylamino-2-nitroethenylamino)ethylthiometh yl]-2- furyl¿methyl)ammonium chloride, C(13)H(23)N(4)O(3)S(+).Cl(-), protonation occurs at the dimethylamino N atom. The ranitidine molecule adopts an eclipsed conformation. Bond lengths indicate extensive electron delocalization in the N,N'-dimethyl-2-nitro-1, 1-ethenediamine system of the molecule. The nitro and methylamino groups are trans across the side chain C=C double bond, while the ethylamino and nitro groups are cis. The Cl(-) ions link molecules through hydrogen bonds.


Asunto(s)
Antagonistas de los Receptores H2 de la Histamina/química , Ranitidina/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular
13.
J Forensic Sci ; 45(3): 582-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10855962

RESUMEN

A nonrandom sample of North American cases of sudden mass assault by a single individual (SMASI, n = 30) is compared with a nonrandom sample of Laotian amok cases (n = 18) and other amok studies. Perpetrators in both studies show evidence of social isolation, loss, depression, anger, pathological narcissism, and paranoia, often to a psychotic degree. The term "innovative perpetrator" is reintroduced and expanded upon. Similarities among samples far outweigh differences, leading the authors to conclude that SMASI and its appearance in different cultures is not a culture-bound syndrome.


Asunto(s)
Psiquiatría Forense , Homicidio/etnología , Adolescente , Adulto , Características Culturales , Trastorno Depresivo , Homicidio/psicología , Humanos , Laos/etnología , Masculino , Persona de Mediana Edad , Trastornos Paranoides , Autoimagen , Conducta Social
15.
Acta Crystallogr C ; 55 ( Pt 7): 1173-5, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10444818

RESUMEN

The asymmetric unit of the title compound, C8H18N3OP, contains one bis(2,2-dimethylaziridinyl)phosphinic amide molecule. The crystal structure is characterized by hydrogen bonds from the amide-N atom, which involve both H atoms of the amino group, to the phosphinic-O atom in two different molecules, thus forming infinite double-stranded chains along the base vector [100], and by hydrophobic contacts between these chains.


Asunto(s)
Antineoplásicos/química , Aziridinas/química , Ácidos Fosfínicos/química , Cristalización , Cristalografía por Rayos X , Neoplasias Esofágicas/tratamiento farmacológico , Humanos , Estructura Molecular , Mieloma Múltiple/tratamiento farmacológico
17.
Autoimmunity ; 29(4): 291-7, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10433085

RESUMEN

The purpose of this study was to investigate the frequency of occurrence of autoantibodies against G-protein coupled cardiovascular receptors and their relation to the clinical manifestation of hypertrophic cardiomyopathy (HCM). Autoantibodies against beta1-receptors, Muscarin-2-receptors, Angiotensin-II-receptor subtype 1 and alpha1-receptors were determined with ELISA in 52 patients with HCM (37 male, 15 female, mean age 55 +/- 15 years) and 40 healthy, age and sex matched controls. The clinical characterization of the HCM-patients included ECG, 24-h Holter, and echocardiography. The results showed that there is no significant difference in the frequency of a single autoantibody between HCM-patients and controls. However, if the number of patients who have autoantibodies against beta1-receptors and/or Muscarin-2-receptors were counted together, there are significantly more autoantibodies in HCM compared to controls (11 vs. 2, p = 0.035). Analysis of clinical data from this pooled group of patients showed that in patients with autoantibodies, heart rate variability (HRV), ultra low frequency (ULF) and very low frequency (VLF) were decreased (HRV by 20%, ULF by 50%, and VLF by 46%, p < 0.008) whereas the QTc-interval was increased by 8% (p < 0.02 each). The ratio of septal to posterior wall thickness was increased by 23% (p = 0.05), and the preejection period was prolonged by 46% in patients with autoantibodies (p < 0.001). These results suggest that the existence of these autoantibodies could be associated with an advanced stage or a severe manifestation of HCM.


Asunto(s)
Autoanticuerpos/inmunología , Cardiomiopatía Hipertrófica/inmunología , Miocardio/inmunología , Receptores de Superficie Celular/inmunología , Adulto , Anciano , Secuencia de Aminoácidos , Cardiomiopatía Hipertrófica/fisiopatología , Femenino , Proteínas de Unión al GTP/inmunología , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Miocardio/metabolismo , Receptores Adrenérgicos alfa/inmunología , Receptores Adrenérgicos beta/inmunología , Receptores de Angiotensina/inmunología , Receptores Muscarínicos/inmunología
18.
J Am Acad Psychiatry Law ; 27(2): 213-25, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10400430

RESUMEN

A nonrandom sample (N = 30) of mass murderers in the United States and Canada during the past 50 years was studied. Data suggest that such individuals are single or divorced males in their fourth decade of life with various Axis I paranoid and/or depressive conditions and Axis II personality traits and disorders, usually Clusters A and B. The mass murder is precipitated by a major loss related to employment or relationship. A warrior mentality suffuses the planning and attack behavior of the subject, and greater deaths and higher casualty rates are significantly more likely if the perpetrator is psychotic at the time of the offense. Alcohol plays a very minor role. A large proportion of subjects will convey their central motivation in a psychological abstract, a phrase or sentence yelled with great emotion at the beginning of the mass murder; but in our study sample, only 20 percent directly threatened their victims before the offense. Death by suicide or at the hands of others is the usual outcome for the mass murderer.


Asunto(s)
Homicidio/legislación & jurisprudencia , Adolescente , Adulto , Trastorno Depresivo/psicología , Armas de Fuego , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Personalidad/diagnóstico , Trastornos de la Personalidad/psicología , Escalas de Valoración Psiquiátrica , Estudios Retrospectivos , Suicidio/psicología
19.
Acta Crystallogr C ; 55 ( Pt 4): 632-3, 1999 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10227128

RESUMEN

In the title compound, 1-(2-deoxy-2-fluoro-beta-D-arabino-furanosyl)-5-fluoropyrimidine-2, 4(1H,3H)-dione, C9H10-F2N2O5, the furanosyl ring adopts the twisted conformation (T) with O1' endo and C1' exo. The crystal structure is characterized by a three-dimensional hydrogen-bond network involving the three H atoms bonded to heteroatoms.


Asunto(s)
Antineoplásicos/química , Antivirales/química , Arabinofuranosil Uracilo/análogos & derivados , Cristalografía por Rayos X , Arabinofuranosil Uracilo/química , Modelos Moleculares
20.
Acta Crystallogr C ; 55 ( Pt 4): 697-8, 1999 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-10227130

RESUMEN

The crystal structure the Schiff base contains one 4-dimethylaminomethyleneaminobenzenesulfonic acid molecule in zwitterionic form [4-(dimethylaminomethyleneammonio)benzenesulfonate], and one water molecule in the asymmetric unit (C9H12N2O3S.H2O). Protonation occurs at nitrogen atom N1, but the charge is delocalized.


Asunto(s)
Cristalografía por Rayos X , Dimetilformamida/química , Bases de Schiff/química , Ácidos Sulfanílicos/química , Modelos Moleculares
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