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1.
J Synchrotron Radiat ; 31(Pt 2): 363-377, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38386565

RESUMEN

The ForMAX beamline at the MAX IV Laboratory provides multiscale and multimodal structural characterization of hierarchical materials in the nanometre to millimetre range by combining small- and wide-angle X-ray scattering with full-field microtomography. The modular design of the beamline is optimized for easy switching between different experimental modalities. The beamline has a special focus on the development of novel fibrous materials from forest resources, but it is also well suited for studies within, for example, food science and biomedical research.

2.
Ultrasound Obstet Gynecol ; 59(4): 465-473, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34725869

RESUMEN

OBJECTIVES: Improvement in the antenatal diagnosis of placenta accreta spectrum (PAS) would allow preparation for delivery in a referral center, leading to decreased maternal morbidity and mortality. Our objectives were to assess the performance of classic ultrasound signs and to determine the value of novel ultrasound signs in the detection of PAS. METHODS: This was a retrospective cohort study of women with second-trimester placenta previa who underwent third-trimester transvaginal ultrasound and all women with PAS in seven medical centers. A retrospective image review for signs of PAS was conducted by three maternal-fetal medicine physicians. Classic signs of PAS were defined as placental lacunae, bladder-wall interruption, myometrial thinning and subplacental hypervascularity. Novel signs were defined as small placental lacunae, irregular placenta-myometrium interface (PMI), vascular PMI, non-tapered placental edge and placental bulge towards the bladder. PAS was diagnosed based on difficulty in removing the placenta or pathological examination of the placenta. Multivariate regression analysis was performed and receiver-operating-characteristics (ROC) curves were generated to assess the performance of combined novel signs, combined classic signs and a model combining classic and novel signs. RESULTS: A total of 385 cases with placenta previa were included, of which 55 had PAS (28 had placenta accreta, 11 had placenta increta and 16 had placenta percreta). The areas under the ROC curves for classic markers, novel markers and a model combining classic and novel markers for the detection of PAS were 0.81 (95% CI, 0.75-0.88), 0.84 (95% CI, 0.77-0.90) and 0.88 (95% CI, 0.82-0.94), respectively. A model combining classic and novel signs performed better than did the classic or novel markers individually (P = 0.03). An increasing number of signs was associated with a greater likelihood of PAS. With the presence of 0, 1, 2 and ≥ 3 classic ultrasound signs, PAS was present in 5%, 24%, 57% and 94% of cases, respectively. CONCLUSIONS: We have confirmed the value of classic ultrasound signs of PAS. The use of novel ultrasound signs in combination with classic signs improved the detection of PAS. These findings have clinical implications for the detection of PAS and may help guide the obstetric management of patients diagnosed with these placental disorders. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta Accreta , Placenta Previa , Femenino , Humanos , Placenta/diagnóstico por imagen , Placenta/patología , Placenta Accreta/patología , Placenta Previa/diagnóstico por imagen , Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal
3.
Acta Neurol Scand ; 129(2): 114-22, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23763450

RESUMEN

AIMS: To conduct a psychometric analysis to determine the adequacy of instruments that measure cognition in Alzheimer's disease trials. BACKGROUND: Both the Alzheimer's Disease Assessment Scale - Cognition (ADAS-Cog) and the Neuropsychological Test Battery (NTB) are validated outcome measures for clinical trials in Alzheimer's disease and are approved also for regulatory purposes. However, it is not clear how comparable they are in measuring cognitive function. In fact, many recent trials in Alzheimer's disease patients have failed and it has been questioned if ADAS-Cog still is a sensitive measure. MATERIALS AND METHODS: The present paper examines the psychometric properties of ADAS-Cog and NTB, based on a post hoc analysis of data from a clinical trial (NCT01024660), which was conducted by AstraZeneca, in mild-to-moderate Alzheimer's disease (AD) patients, with a Mini Mental State Examination (MMSE) Total score 16-24. Acceptability, reliability, different types of validity and ability to detect change were assessed using relevant statistical methods. Total scores of both tests, as well as separate domains of both tests, including the Wechsler Memory Scale (WMS), Rey Auditory Verbal Learning Test (RAVLT) and Delis-Kaplan Executive Function System (D-KEFS) Verbal Fluency Condition, were analyzed. RESULTS: Overall, NTB performed well, with acceptable reliability and ability to detect change, while ADAS-Cog had insufficient psychometric properties, including ceiling effects in 8 out of a total of 11 ADAS-Cog items in mild AD patients, as well as low test-retest reliability in some of the items. DISCUSSION: Based on a direct comparison on the same patient sample, we see advantages of the NTB compared with the ADAS-Cog for the evaluation of cognitive function in the population of mild-to-moderate AD patients. The results suggest that not all of ADAS-Cog items are relevant for both mild and moderate AD population. CONCLUSIONS: This validation study demonstrates satisfactory psychometric properties of the NTB, while ADAS-Cog was found to be psychometrically inadequate.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Cognición/efectos de los fármacos , Pruebas Neuropsicológicas , Nootrópicos/uso terapéutico , Anciano , Anciano de 80 o más Años , Donepezilo , Femenino , Humanos , Indanos/uso terapéutico , Masculino , Persona de Mediana Edad , Piperidinas/uso terapéutico , Psicometría , Ensayos Clínicos Controlados Aleatorios como Asunto
4.
Scand J Med Sci Sports ; 24(6): 1000-5, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24033718

RESUMEN

Physical training has been shown to reduce mortality in normal subjects, and athletes have a healthier lifestyle after their active career as compared with normal subjects. Since the 1950s, the use of anabolic androgenic steroids (AAS) has been frequent, especially in power sports. The aim of the present study was to investigate mortality, including causes of death, in former Swedish male elite athletes, active 1960-1979, in wrestling, powerlifting, Olympic lifting, and the throwing events in track and field when the suspicion of former AAS use was high. Results indicate that, during the age period of 20-50 years, there was an excess mortality of around 45%. However, when analyzing the total study period, the mortality was not increased. Mortality from suicide was increased 2-4 times among the former athletes during the period of 30-50 years of age compared with the general population of men. Mortality rate from malignancy was lower among the athletes. As the use of AAS was marked between 1960 and 1979 and was not doping-listed until 1975, it seems probable that the effect of AAS use might play a part in the observed increased mortality and suicide rate. The otherwise healthy lifestyle among the athletes might explain the low malignancy rates.


Asunto(s)
Causas de Muerte , Suicidio/estadística & datos numéricos , Atletismo/estadística & datos numéricos , Levantamiento de Peso/estadística & datos numéricos , Lucha/estadística & datos numéricos , Adulto , Anabolizantes/uso terapéutico , Doping en los Deportes , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Mortalidad , Neoplasias/mortalidad , Suecia/epidemiología , Adulto Joven
5.
Clin Genet ; 83(6): 553-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22998390

RESUMEN

Bardet-Biedl syndrome (BBS) is a rare pediatric ciliopathy characterized by marked clinical variability and extensive genetic heterogeneity. Typical diagnosis of BBS is secured at a median of 9 years of age, and sometimes well into adolescence. Here, we report a patient in whom prenatal detection of increased nuchal fold, enlarged echogenic kidneys, and polydactyly prompted us to screen the most commonly mutated genes in BBS and the phenotypically and genetically overlapping ciliopathy, Meckel-Gruber syndrome (MKS). We identified the common Met390Arg mutation in BBS1 in compound heterozygosity with a novel intronic variant of unknown significance (VUS). Testing of mRNA harvested from primary foreskin fibroblasts obtained shortly after birth revealed the VUS to induce a cryptic splice site, which in turn led to a premature termination and mRNA degradation. To our knowledge, this is the earliest diagnosis of BBS in the absence of other affected individuals in the family, and exemplifies how combining clinical assessment with genetic and timely assays of variant pathogenicity can inform clinical diagnosis and assist with patient management in the prenatal and neonatal setting.


Asunto(s)
Síndrome de Bardet-Biedl/genética , Pruebas Genéticas/métodos , Proteínas Asociadas a Microtúbulos/genética , Mutación , Ultrasonografía Prenatal , Secuencia de Aminoácidos , Síndrome de Bardet-Biedl/diagnóstico , Secuencia de Bases , Células Cultivadas , Análisis Mutacional de ADN , Femenino , Fibroblastos/metabolismo , Prepucio/citología , Humanos , Recién Nacido , Masculino , Embarazo
6.
Br J Sports Med ; 47(15): 965-9, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23613517

RESUMEN

BACKGROUND: The knowledge concerning the long-term effect of former anabolic androgenic steroids (AAS)-use on mental health is sparse. AIM: This study aims to investigate whether previous AAS-use affects mental health, present sociodemographic data, sport activity and substance abuse in a retrospective 30-year follow-up study of former elite athletes. METHODS: Swedish male-elite power sport athletes (n=683) on the top 10 national ranking lists during any of the years 1960-1979 in wrestling, Olympic lifting, powerlifting and the throwing events in track and field answered a questionnaire. RESULTS: At least 20% of the former athletes admitted previous AAS-use. They had more often sought professional expertise for mental problems and had used illicit drugs compared to those not having used AAS. The AAS-users also differed in former sport activity pattern compared to non AAS-users. CONCLUSIONS: It is clear that a relationship exists between use of AAS and mental-health problems. Further studies need to be done in order to clarify this relationship.


Asunto(s)
Anabolizantes/efectos adversos , Doping en los Deportes/psicología , Trastornos Mentales/epidemiología , Deportes/psicología , Trastornos Relacionados con Sustancias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Aceptación de la Atención de Salud/estadística & datos numéricos , Estudios Retrospectivos , Deportes/estadística & datos numéricos , Trastornos Relacionados con Sustancias/psicología , Suecia/epidemiología
7.
Rev Sci Tech ; 31(3): 997-1010, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23520753

RESUMEN

The aim of this study was to evaluate the general characteristics of commercially available enzyme-linked immunosorbent assays (ELISAs) to detect antibody against classical swine fever (CSF), as well as to assess their potential use as accompanying marker tests able to differentiate infected from vaccinated animals (DIVA). The Chekit* CSF-Sero and the HerdChek* CSFV Ab, both of which detect antibodies against the E2 protein of classical swine fever virus (CSFV), had the highest sensitivity. Both tests were practicable and showed good reproducibility. Comparable sensitivity was shown by the Chekit* CSF-Marker, an Erns ELISA. However, this test does not allow differentiation between antibodies directed against ruminant pestiviruses and those against CSFV. Therefore, it is not suitable for use with the chimeric marker vaccines tested. The PrioCHECK CSFV Erns was the only ELISA suitable for use in DIVA with marker vaccines containing Erns proteins from ruminant pestiviruses. However, this test was less sensitive and selective than the E2-ELISAs and cannot be recommended.


Asunto(s)
Anticuerpos Antivirales/sangre , Virus de la Fiebre Porcina Clásica/inmunología , Peste Porcina Clásica/diagnóstico , Ensayo de Inmunoadsorción Enzimática/veterinaria , Vacunación/veterinaria , Animales , Peste Porcina Clásica/inmunología , Peste Porcina Clásica/prevención & control , Ensayo de Inmunoadsorción Enzimática/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Porcinos , Vacunación/estadística & datos numéricos , Vacunas Atenuadas , Vacunas Virales
8.
eNeuro ; 7(1)2020.
Artículo en Inglés | MEDLINE | ID: mdl-32015098

RESUMEN

Developmental cell death eliminates half of the neurons initially generated in the mammalian brain, and occurs perinatally in many species. It is possible that the timing of neuronal cell death is developmentally programmed, and only coincidentally associated with birth. Alternatively, birth may play a role in shaping cell death. To test these competing hypotheses, we experimentally advanced or delayed birth by 1 d in mice (within the normal range of gestation for the species) and examined effects on the temporal pattern and magnitude (amount) of neuronal cell death, using immunohistochemical detection of activated caspase-3 as a cell death marker. In order to detect effects of subtle changes in birth timing, we focused on brain areas that exhibit sharp postnatal peaks in cell death. We find that advancing birth advances peak cell death, supporting the hypothesis that birth triggers cell death. However, a delay of birth does not delay cell death. Thus, birth can advance cell death, but if postponed, a developmental program governs. Advancing or delaying birth also caused region-specific changes in the overall magnitude of cell death. Our findings shed light on the long-standing question of what controls the timing and magnitude of developmental neuronal cell death, and position birth as an orchestrator of brain development. Because humans across the world now routinely alter birth timing, these findings may have implications for current obstetric practices.


Asunto(s)
Encéfalo , Parto , Animales , Apoptosis , Muerte Celular , Femenino , Ratones , Neuronas , Embarazo
9.
Environ Syst Decis ; 40(2): 252-286, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32837821

RESUMEN

In the moment of preparation of this paper, the world is still globally in grip of the Corona (COVID-19) crisis, and the need to understand the broader overall framework of the crisis increases. As in similar cases in the past, also with this one, the main interest is on the "first response". Fully appreciating the efforts of those risking their lives facing pandemics, this paper tries to identify the main elements of the larger, possibly global, framework, supported by international standards, needed to deal with new (emerging) risks resulting from threats like Corona and assess the resilience of systems affected. The paper proposes that future solutions should include a number of new elements, related to both risk and resilience. That should include broadening the scope of attention, currently focused onto preparation and response phases, to the phases of "understanding risks", including emerging risks, and transformation and adaptation. The paper suggests to use resilience indicators in this process. The proposed approach has been applied in different cases involving critical infrastructures in Europe (energy supply, water supply, transportation, etc., exposed to various threats), including the health system in Austria. The detailed, indicator-based, resilience analysis included mapping resilience, resilience stress-testing, visualization, etc., showing, already before the COVID-19, the resilience (stress-testing) limits of the infrastructures. A simpler (57 indicator based) analysis has, then been done for 11 countries (including Austria). The paper links these results with the options available in the area of policies, standards, guidelines and tools (such as the RiskRadar), with focus on interdependencies and global standards-especially the new ISO 31,050, linking emerging risks and resilience.

10.
Neuron ; 21(3): 531-43, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9768840

RESUMEN

Capsaicin, the main pungent ingredient in "hot" chili peppers, elicits buming pain by activating specific (vanilloid) receptors on sensory nerve endings. The cloned vanilloid receptor (VR1) is a cation channel that is also activated by noxious heat. Here, analysis of heat-evoked single channel currents in excised membrane patches suggests that heat gates VR1 directly. We also show that protons decrease the temperature threshold for VR1 activation such that even moderately acidic conditions (pH < or = 5.9) activate VR1 at room temperature. VR1 can therefore be viewed as a molecular integrator of chemical and physical stimuli that elicit pain. Immunocytochemical analysis indicates that the receptor is located in a neurochemically heterogeneous population of small diameter primary afferent fibers. A role for VR1 in injury-induced hypersensitivity at the level of the sensory neuron is presented.


Asunto(s)
Capsaicina/farmacología , Fibras Nerviosas/fisiología , Neuronas Aferentes/fisiología , Dolor/fisiopatología , Receptores de Droga/fisiología , Vías Aferentes/fisiología , Secuencia de Aminoácidos , Animales , Línea Celular , Clonación Molecular , Ganglios Espinales/fisiología , Calor , Humanos , Inmunohistoquímica , Masculino , Potenciales de la Membrana/efectos de los fármacos , Modelos Neurológicos , Datos de Secuencia Molecular , Inflamación Neurogénica/fisiopatología , Oocitos/fisiología , Técnicas de Placa-Clamp , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Terminales Presinápticos/fisiología , Terminales Presinápticos/ultraestructura , Ratas , Ratas Sprague-Dawley , Receptores de Droga/biosíntesis , Receptores de Droga/efectos de los fármacos , Proteínas Recombinantes/biosíntesis , Nervio Ciático/fisiología , Médula Espinal/fisiología , Médula Espinal/ultraestructura , Ganglio Cervical Superior/fisiología , Transfección , Xenopus laevis
11.
Growth Horm IGF Res ; 17(3): 220-6, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17339122

RESUMEN

OBJECTIVE: To develop a test for GH abuse in sport. DESIGN: A double blind placebo controlled study of one month's GH administration to 102 healthy non-competing but trained subjects. Blood levels of nine markers of GH action were measured throughout the study and for 56 days after cessation of GH administration. Blood samples were also taken from 813 elite athletes both in and out of competition. RESULTS: GH caused a significant change in the nine measured blood markers. Men were more sensitive to the effects of GH than women. IGF-I and N-terminal extension peptide of procollagen type III were selected to construct formulae which gave optimal discrimination between the GH and placebo groups. Adjustments were made to account for the fall in IGF-I and P-III-P with age and the altered distribution seen in elite athletes. Using a cut-off specificity of 1:10,000 these formulae would allow the detection of up to 86% of men and 60% of women abusing GH at the doses used in this study. CONCLUSIONS: We report a methodology that will allow the detection of GH abuse. This will provide the basis of a robust and enforceable test identifying those who are already cheating and provide a deterrent to those who may be tempted to do so.


Asunto(s)
Doping en los Deportes , Hormona del Crecimiento/administración & dosificación , Factor I del Crecimiento Similar a la Insulina/análisis , Fragmentos de Péptidos/sangre , Procolágeno/sangre , Trastornos Relacionados con Sustancias/diagnóstico , Adolescente , Adulto , Biomarcadores/sangre , Método Doble Ciego , Femenino , Humanos , Masculino , Placebos
12.
J Perinatol ; 27(4): 244-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17377607

RESUMEN

Neostigmine is a treatment option for colonic pseudoobstruction. However, experience in using neostigmine for this indication in pregnant women is limited. We present a case of a woman with an estimated fetal gestational age of 34 weeks presented with what was believed to be a pseudoobstruction and when conservative management failed, neostigmine was administered with no adverse side effects. Ultimately, the patient was found to have a mechanical obstruction and we discuss the challenges in making this diagnosis in pregnancy. Neostigmine may be a viable alternative to colonoscopy in pregnant women for whom mechanical obstruction is properly excluded.


Asunto(s)
Seudoobstrucción Colónica/tratamiento farmacológico , Vólvulo Intestinal/diagnóstico , Neostigmina/uso terapéutico , Parasimpaticomiméticos/uso terapéutico , Complicaciones del Embarazo/tratamiento farmacológico , Dolor Abdominal/etiología , Adulto , Colectomía , Seudoobstrucción Colónica/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Vólvulo Intestinal/cirugía , Embarazo , Complicaciones del Embarazo/diagnóstico , Insuficiencia del Tratamiento
13.
J Sci Med Sport ; 20(9): 814-818, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28389219

RESUMEN

OBJECTIVES: The aim of the present study was to investigate the association between somatic health and former abuse of AAS in former elite male athletes 30 years after the end of their active sports career. DESIGN: Retrospective follow-up study. METHODS: N=996 former elite male athletes were sent a questionnaire concerning sociodemographic variables, previous and past sport activity and lifetime prevalence of seeking professional help for health problems. N=683 (68.6%) answered the questionnaire. The lifetime prevalence of AAS-abuse was 21% (n=143), while 79% (n=540) did not admit having ever used AAS. RESULTS: Former AAS-abuse was associated with tendon ruptures (p=0.01), depression (p=0.001), anxiety (p=0.01) and lower prevalence of prostate hypertrophy (p=0.01) and decreased libido (p=0.01). Former advanced AAS-abusers had higher anxiety (p=0.004) compared to the former less advanced AAS-abusers. Moreover, former advanced AAS-abusers, compared to AAS-naïves, reported more psychiatric problems (p=0.002), depression (p=0.003) and anxiety (p=0.00). CONCLUSIONS: A former AAS-abuse seems to be associated with some somatic and mental health problem, although a former less advanced AAS-abuse is related to lower incidence of prostate hypertrophy. The results raise the question whether some of these associations might be dose- and frequency dependent. These findings should however be seen as hypothesis generating and further studies are needed.


Asunto(s)
Anabolizantes/efectos adversos , Atletas , Doping en los Deportes , Levantamiento de Peso , Anciano , Ansiedad/epidemiología , Depresión/epidemiología , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Próstata/patología , Estudios Retrospectivos , Rotura/epidemiología , Encuestas y Cuestionarios , Suecia , Traumatismos de los Tendones/epidemiología
14.
Rofo ; 177(9): 1260-6, 2005 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-16123873

RESUMEN

PURPOSE: Until now, no mechanical closure devices were available to achieve fast and secure hemostasis for vessel closure after catheterization of small arterial vessels. MATERIAL AND METHODS: Eighty patients were randomized to evaluate the effect on hemostasis by use of a chitosan pad (Chito-Seal, Abbott Vascular Devices, Galway/Ireland) in comparison to manual compression after diagnostic transbrachial arterial catheterization. Hemostasis after three minutes and one hour as well as local development of a hematoma after one and twenty-four hours were assessed. RESULTS: The use of chitosan pads significantly decreased the bleeding time in the first three minutes after manual compression time (p < 0.01). Significant decrease in bleeding risk at three minutes by use of the chitosan closure pads was also found in subgroups of patients with hypertension (p < 0.001) or diabetes (p < 0.01) and also in patients under anticoagulation therapy (p < 0.01). In addition, long-term protection from bleeding complications such as the risk of hematoma was decreased by the use of chitosan closure pads one hour (p < 0.01) or twenty-four hours (p < 0.001) after catheter removal. CONCLUSION: The use of an intravascular anchor or suture system is not safely applicable in these vessels due to the small diameter of the brachial artery. Our results document a significant improvement in hemostasis by using chitosan pads in these cases.


Asunto(s)
Angiografía , Cateterismo Periférico , Quitosano/administración & dosificación , Hematoma/prevención & control , Técnicas Hemostáticas , Hemostáticos/administración & dosificación , Anticoagulantes/uso terapéutico , Arteria Braquial , Complicaciones de la Diabetes , Femenino , Humanos , Hipertensión/complicaciones , Masculino , Factores de Riesgo , Factores de Tiempo
15.
Arch Intern Med ; 148(8): 1825-7, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3401105

RESUMEN

We report a case of Vibrio vulnificus infection in a middle-aged alcoholic man with Laennec's cirrhosis. The patient had recently received a puncture wound from the shell of a shrimp while fishing in the Gulf of Mexico. He presented with acrally distributed urticarial plaques, purpura, and bullae, as well as signs and symptoms of septic shock. Vibrio vulnificus was isolated from the blood, and histologic examination of the skin biopsy specimen demonstrated a devitalized, inflammatory, cell-poor superficial dermis and an acute cellulitis of the subcutis, with extensive tissue destruction. In addition, a necrotizing vasculitis, with a relative paucity of inflammatory cells but numerous bacilli around dermal vessels, was noted.


Asunto(s)
Sepsis , Vibriosis , Humanos , Masculino , Persona de Mediana Edad , Sepsis/etiología , Sepsis/patología , Vibriosis/etiología , Vibriosis/patología
16.
Arch Intern Med ; 150(4): 752-6, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2327836

RESUMEN

To determine the diagnostic accuracy of iofetamine hydrochloride I 123 (IMP) with single photon emission computed tomography in Alzheimer's disease, we studied 58 patients with AD and 15 age-matched healthy control subjects. We used a qualitative method to assess regional IMP uptake in the entire brain and to rate image data sets as normal or abnormal without knowledge of subjects'clinical classification. The sensitivity and specificity of IMP with single photon emission computed tomography in AD were 88% and 87%, respectively. In 15 patients with mild cognitive deficits (Blessed Dementia Scale score, less than or equal to 10), sensitivity was 80%. With the use of a semiquantitative measure of regional cortical IMP uptake, the parietal lobes were the most functionally impaired in AD and the most strongly associated with the patients' Blessed Dementia Scale scores. These results indicated that IMP with single photon emission computed tomography may be a useful adjunct in the clinical diagnosis of AD in early, mild disease.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Anfetaminas , Radioisótopos de Yodo , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Yofetamina , Masculino
17.
Cardiovasc Res ; 27(3): 459-63, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8490947

RESUMEN

OBJECTIVE: When cardiac sympathetic innervation in neonatal rats is retarded by antiserum to nerve growth factor, there is a corresponding increase in the QT interval on ECG. Since the propagation of the cardiac impulse and the repolarisation of cardiac cells both contribute to the QT interval, the aim of this study was to determine the role of sympathetic innervation in modulating ventricular impulse propagation and repolarisation. METHODS: Neonatal rats were treated for the first 10 days of life with nerve growth factor (NGF), its antiserum (As), or placebo. Standard microelectrode techniques were used to study the transmembrane action potential characteristics of subendocardial (ventricular septal) and subepicardial ventricular myocardium. Bipolar surface electrograms were used to record the velocity of impulse propagation and electron microscopy to examine the intercalated discs. RESULTS: In the subendocardium, the phase 0 upstroke velocity of the action potential (dV/dtmax) was lowest in the As treated rats. The latter group also showed the slowest conduction velocity. There were no differences in control action potential durations in the endocardium among the three groups, but in the epicardial tissues, action potential duration was longest in the As treated group. Thus the dispersion in action potential duration was smallest in the As treated animals. Electron microscopic studies of the intercalated discs of ventricular myocytes showed significant enhancement of nexal junction formation in NGF treated rats, whereas As treated animals showed a retarded pattern of both nexal and desmosomal junction formation. CONCLUSIONS: The differences in ultrastructure, conduction, and repolarisation seen in As and NGF treated animals may explain the prolonged QT interval seen in the As treated group.


Asunto(s)
Corazón/inervación , Factores de Crecimiento Nervioso/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Animales Recién Nacidos , Desmosomas , Electrocardiografía , Proteínas de Unión al GTP/análisis , Frecuencia Cardíaca , Ventrículos Cardíacos , Miocardio/química , Ratas , Ratas Wistar
18.
Artículo en Inglés | MEDLINE | ID: mdl-26066258

RESUMEN

This work describes the inertial effects on the rotational behavior of an oblate spheroidal particle confined between two parallel opposite moving walls, which generate a linear shear flow. Numerical results are obtained using the lattice Boltzmann method with an external boundary force. The rotation of the particle depends on the particle Reynolds number, Re(p)=Gd(2)ν(-1) (G is the shear rate, d is the particle diameter, ν is the kinematic viscosity), and the Stokes number, St=αRe(p) (α is the solid-to-fluid density ratio), which are dimensionless quantities connected to fluid and particle inertia, respectively. The results show that two inertial effects give rise to different stable rotational states. For a neutrally buoyant particle (St=Re(p)) at low Re(p), particle inertia was found to dominate, eventually leading to a rotation about the particle's symmetry axis. The symmetry axis is in this case parallel to the vorticity direction; a rotational state called log-rolling. At high Re(p), fluid inertia will dominate and the particle will remain in a steady state, where the particle symmetry axis is perpendicular to the vorticity direction and has a constant angle ϕ(c) to the flow direction. The sequence of transitions between these dynamical states were found to be dependent on density ratio α, particle aspect ratio r(p), and domain size. More specifically, the present study reveals that an inclined rolling state (particle rotates around its symmetry axis, which is not aligned in the vorticity direction) appears through a pitchfork bifurcation due to the influence of periodic boundary conditions when simulated in a small domain. Furthermore, it is also found that a tumbling motion, where the particle symmetry axis rotates in the flow-gradient plane, can be a stable motion for particles with high r(p) and low α.


Asunto(s)
Hidrodinámica , Fenómenos Mecánicos , Modelos Teóricos , Rotación , Reología
19.
Placenta ; 36(5): 581-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25771405

RESUMEN

INTRODUCTION: Our recent studies have shown that constitutively activated non-canonical RelB/NF-κB2 (p52) in the human placenta positively regulates the pro-labor genes CRH and COX-2. STAT3 regulates NF-κB2 (p100) processing to active p52, and in turn, nuclear activation of RelB/p52, by directly binding to p100/p52 in a variety of cancer cells. In the current study, we tested the hypothesis that STAT3 is involved in regulation of pro-labor genes by associating with RelB/p52 heterodimers in the human placenta. METHODS: We used a variety of techniques including immunohistochemical staining, gene silencing, ectopic expression, chromatin immunoprecipitation, Western blot, RT-qPCR, and immunofluorescence assays in primary culture of cytotrophoblast and placental tissues. RESULTS: We found that knockdown of STAT3 led to down-regulation of both CRH and COX-2 in a dose-dependent manner. By using chromatin immunoprecipitation, we further showed that interaction of RelB with the CRH or COX-2 gene promoters decreased when STAT3 was depleted. Immunofluorescence demonstrated co-localization of STAT3 with RelB or p100/p52 in both the cytoplasm and nucleus of term cytotrophoblasts. DISCUSSION: Collectively, these results suggest that STAT3 constitutes part of the RelB/p52-containing activator complex that positively regulates pro-labor genes in the human placenta.


Asunto(s)
Hormona Liberadora de Corticotropina/metabolismo , Ciclooxigenasa 2/metabolismo , Regulación del Desarrollo de la Expresión Génica , Placenta/metabolismo , Factor de Transcripción STAT3/metabolismo , Células Cultivadas , Femenino , Humanos , Subunidad p52 de NF-kappa B/metabolismo , Embarazo , Interferencia de ARN , Factor de Transcripción ReIB/metabolismo , Contracción Uterina
20.
Artículo en Inglés | MEDLINE | ID: mdl-26764819

RESUMEN

We numerically analyze the rotation of a neutrally buoyant spheroid in a shear flow at small shear Reynolds number. Using direct numerical stability analysis of the coupled nonlinear particle-flow problem, we compute the linear stability of the log-rolling orbit at small shear Reynolds number Re(a). As Re(a)→0 and as the box size of the system tends to infinity, we find good agreement between the numerical results and earlier analytical predictions valid to linear order in Re(a) for the case of an unbounded shear. The numerical stability analysis indicates that there are substantial finite-size corrections to the analytical results obtained for the unbounded system. We also compare the analytical results to results of lattice Boltzmann simulations to analyze the stability of the tumbling orbit at shear Reynolds numbers of order unity. Theory for an unbounded system at infinitesimal shear Reynolds number predicts a bifurcation of the tumbling orbit at aspect ratio λ(c)≈0.137 below which tumbling is stable (as well as log rolling). The simulation results show a bifurcation line in the λ-Re(a) plane that reaches λ≈0.1275 at the smallest shear Reynolds number (Re(a)=1) at which we could simulate with the lattice Boltzmann code, in qualitative agreement with the analytical results.

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