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1.
Phys Rev Lett ; 131(4): 043603, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566828

RESUMEN

We report the levitation of a superconducting lead-tin sphere with 100 µm diameter (corresponding to a mass of 5.6 µg) in a static magnetic trap formed by two coils in an anti-Helmholtz configuration, with adjustable resonance frequencies up to 240 Hz. The center-of-mass motion of the sphere is monitored magnetically using a dc superconducting quantum interference device as well as optically and exhibits quality factors of up to 2.6×10^{7}. We also demonstrate 3D magnetic feedback control of the motion of the sphere. The setup is housed in a dilution refrigerator operating at 15 mK. By implementing a cryogenic vibration isolation system, we can attenuate environmental vibrations at 200 Hz by approximately 7 orders of magnitude. The combination of low temperature, large mass, and high quality factor provides a promising platform for testing quantum physics in previously unexplored regimes with high mass and long coherence times.

2.
Br J Cancer ; 125(11): 1462-1465, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34316019

RESUMEN

The National Cancer Imaging Translational Accelerator (NCITA) is creating a UK national coordinated infrastructure for accelerated translation of imaging biomarkers for clinical use. Through the development of standardised protocols, data integration tools and ongoing training programmes, NCITA provides a unique scalable infrastructure for imaging biomarker qualification using multicentre clinical studies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Pruebas Diagnósticas de Rutina/métodos , Neoplasias/diagnóstico por imagen , Humanos , Proyectos de Investigación , Reino Unido
3.
Occup Med (Lond) ; 70(8): 556-563, 2020 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-33150448

RESUMEN

BACKGROUND: Fluid Resistant Surgical Masks have been implemented in UK personal protective equipment (PPE) guidelines for COVID-19 for all care sites that do not include aerosol-generating procedures (AGPs). FFP3 masks are used in AGP areas. Concerns from the ENT and plastic surgery communities out with intensive care units have questioned this policy. Emerging evidence on cough clouds and health care worker deaths has suggested that a review is required. AIMS: To test the efficacy of Fluid Resistant Surgical Mask with and without adaptions for respiratory protection. To test the efficacy of FFP and FFP3 regarding fit testing and usage. METHODS: A smoke chamber test of 5 min to model an 8-h working shift of exposure while wearing UK guideline PPE using an inspiratory breathing mouthpiece under the mask. Photographic data were used for comparison. RESULTS: The Fluid Resistant Surgical Mask gave no protection to inhaled smoke particles. Modifications with tape and three mask layers gave slight benefit but were not considered practical. FFP3 gave complete protection to inhaled smoke but strap tension needs to be 'just right' to prevent facial trauma. Facial barrier creams are an infection risk. CONCLUSIONS: Surgical masks give no protection to respirable particles. Emerging evidence on cough clouds and health care worker deaths suggests the implementation of a precautionary policy of FFP3 for all locations exposed to symptomatic or diagnosed COVID-19 patients. PPE fit testing and usage policy need to improve to include daily buddy checks for FFP3 users.


Asunto(s)
Exposición por Inhalación/prevención & control , Máscaras/normas , Exposición Profesional/prevención & control , Dispositivos de Protección Respiratoria/normas , Humo/análisis , Aerosoles , COVID-19/prevención & control , COVID-19/transmisión , Diseño de Equipo , Seguridad de Equipos , Humanos , Transmisión de Enfermedad Infecciosa de Profesional a Paciente/prevención & control , SARS-CoV-2 , Lesión por Inhalación de Humo/prevención & control , Ventiladores Mecánicos/normas
4.
Lupus ; 24(2): 191-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25335488

RESUMEN

OBJECTIVE: This study evaluated the effects of obesity on health-related quality of life (HRQOL) measures in juvenile-onset systemic lupus erythematosus (jSLE). METHODS: Obesity was defined as a body mass index (BMI) ≥ 95 th percentile according to the Sex-specific Center for Disease Control BMI-For-Age Charts and determined in a multicenter cohort of jSLE patients. In this secondary analysis, the domain and summary scores of the Pediatric Quality of Life (PedsQL) Inventory and the Child Health Questionnaire (CHQ) of obese jSLE patients were compared to those of non-obese jSLE patients as well as historical obese and non-obese healthy controls. Mixed-effects modeling was performed to evaluate the relationship between obesity and HRQOL measures. RESULTS: Among the 202 jSLE patients, 25% (n = 51) were obese. Obesity had a significant negative impact on HRQOL in jSLE, even after adjusting for differences in current corticosteroid use, disease activity, disease damage, gender and race between groups. Obese jSLE patients had lower physical functioning compared to non-obese jSLE patients, and to non-obese and obese healthy controls. Compared to their non-obese counterparts, obese jSLE patients also had worse school functioning, more pain, worse social functioning and emotional functioning. Parents of obese jSLE patients worry more. The CHQ scores for obese jSLE patients were also worse compared to non-obese jSLE patients in several other domains. CONCLUSION: Our study demonstrates the detrimental effects of obesity on patient-reported outcomes in jSLE. This supports the importance of weight management for the therapeutic plan of jSLE.


Asunto(s)
Lupus Eritematoso Sistémico/fisiopatología , Obesidad/complicaciones , Calidad de Vida , Adolescente , Índice de Masa Corporal , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
5.
Am J Transplant ; 14(5): 1183-90, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24731148

RESUMEN

BK viral infection is an important cause of renal transplant dysfunction and failure. Current strategies utilize surveillance for infection with DNA polymerase chain reaction assays and modulation of immunosuppression. Many viruses including polyomaviruses encode microRNAs (miRNAs). We have detected BK virus (BKV) encoded miRNAs in the blood of infected renal transplant recipients, and see a strong correlation between BKV encoded miRNA and BKV DNA in blood and a relationship between levels of bkv-miR-B1-5p and the presence of biopsy-proven BK viral nephropathy. Further research is needed to determine whether the detection of this and other virally encoded miRNAs may be useful in the diagnosis of active viral replication.


Asunto(s)
Virus BK/genética , Enfermedades Renales/diagnóstico , Trasplante de Riñón , MicroARNs/sangre , Infecciones por Polyomavirus/diagnóstico , Receptores de Trasplantes , Virus BK/aislamiento & purificación , Estudios de Casos y Controles , ADN Viral/genética , Femenino , Estudios de Seguimiento , Regulación Viral de la Expresión Génica , Humanos , Enfermedades Renales/sangre , Enfermedades Renales/virología , Masculino , MicroARNs/genética , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Infecciones por Polyomavirus/sangre , Infecciones por Polyomavirus/virología , Pronóstico , ARN Mensajero/genética , ARN Viral/sangre , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Replicación Viral
6.
Arthritis Rheum ; 64(1): 285-96, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22031171

RESUMEN

OBJECTIVE: Statins reduce atherosclerosis and cardiovascular morbidity in the general population, but their efficacy and safety in children and adolescents with systemic lupus erythematosus (SLE) are unknown. This study was undertaken to determine the 3-year efficacy and safety of atorvastatin in preventing subclinical atherosclerosis progression in pediatric-onset SLE. METHODS: A total of 221 participants with pediatric SLE (ages 10-21 years) from 21 North American sites were enrolled in the Atherosclerosis Prevention in Pediatric Lupus Erythematosus study, a randomized double-blind, placebo-controlled clinical trial, between August 2003 and November 2006 with 36-month followup. Participants were randomized to receive atorvastatin (n=113) or placebo (n=108) at 10 or 20 mg/day depending on weight, in addition to usual care. The primary end point was progression of mean-mean common carotid intima-media thickening (CIMT) measured by ultrasound. Secondary end points included other segment/wall-specific CIMT measures, lipid profile, high-sensitivity C-reactive protein (hsCRP) level, and SLE disease activity and damage outcomes. RESULTS: Progression of mean-mean common CIMT did not differ significantly between treatment groups (0.0010 mm/year for atorvastatin versus 0.0024 mm/year for placebo; P=0.24). The atorvastatin group achieved lower hsCRP (P=0.04), total cholesterol (P<0.001), and low-density lipoprotein (P<0.001) levels compared with placebo. In the placebo group, CIMT progressed significantly across all CIMT outcomes (0.0023-0.0144 mm/year; P<0.05). Serious adverse events and critical safety measures did not differ between groups. CONCLUSION: Our results indicate that routine statin use over 3 years has no significant effect on subclinical atherosclerosis progression in young SLE patients; however, further analyses may suggest subgroups that would benefit from targeted statin therapy. Atorvastatin was well tolerated without safety concerns.


Asunto(s)
Anticolesterolemiantes/uso terapéutico , Aterosclerosis/prevención & control , Ácidos Heptanoicos/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Pirroles/uso terapéutico , Adolescente , Aterosclerosis/complicaciones , Aterosclerosis/diagnóstico , Atorvastatina , Grosor Intima-Media Carotídeo , Niño , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Humanos , Lípidos/sangre , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/complicaciones , Masculino , Resultado del Tratamiento , Adulto Joven
7.
ESMO Open ; 8(4): 101615, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37562195

RESUMEN

BACKGROUND: Approximately 80% of all breast cancers (BCs) are currently categorized as human epidermal growth factor receptor 2 (HER2)-negative [immunohistochemistry (IHC) 0, 1+, or 2+/in situ hybridization (ISH) negative]; approximately 60% of BCs traditionally categorized as HER2-negative express low levels of HER2. HER2-low (IHC 1+ or IHC 2+/ISH-) status became clinically actionable with approval of trastuzumab deruxtecan to treat unresectable/metastatic HER2-low BC. Greater understanding of patients with HER2-low disease is urgently needed. PATIENTS AND METHODS: This global, multicenter, retrospective study (NCT04807595) included tissue samples from patients with confirmed HER2-negative unresectable/metastatic BC [any hormone receptor (HR) status] diagnosed from 2014 to 2017. Pathologists rescored HER2 IHC-stained slides as HER2-low (IHC 1+ or IHC 2+/ISH-) or HER2 IHC 0 after training on low-end expression scoring using Ventana 4B5 and other assays at local laboratories (13 sites; 10 countries) blinded to historical scores. HER2-low prevalence and concordance between historical scores and rescores were assessed. Demographics, clinicopathological characteristics, treatments, and outcomes were examined. RESULTS: In rescored samples from 789 patients with HER2-negative unresectable/metastatic BC, the overall HER2-low prevalence was 67.2% (HR positive, 71.1%; HR negative, 52.8%). Concordance was moderate between historical and rescored HER2 statuses (81.3%; κ = 0.583); positive agreement was numerically higher for HER2-low (87.5%) than HER2 IHC 0 (69.9%). More than 30% of historical IHC 0 cases were rescored as HER2-low overall (all assays) and using Ventana 4B5. There were no notable differences between HER2-low and HER2 IHC 0 in patient characteristics, treatments received, or clinical outcomes. CONCLUSIONS: Approximately two-thirds of patients with historically HER2-negative unresectable/metastatic BC may benefit from HER2-low-directed treatments. Our data suggest that HER2 reassessment in patients with historical IHC 0 scores may be considered to help optimize selection of patients for treatment. Further, accurate identification of patients with HER2-low BC may be achieved with standardized pathologist training.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/terapia , Neoplasias de la Mama/diagnóstico , Estudios Retrospectivos , Prevalencia , Receptor ErbB-2/genética , Hibridación in Situ
8.
J Plast Reconstr Aesthet Surg ; 75(2): 613-620, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34728156

RESUMEN

INTRODUCTION: Reconstruction of fingers pose unique challenges, as a thin and flexible flap is needed in order to guarantee a good functional outcome. For the first time, in this report, we present the DBAp (distal brachial artery perforator) flap, based on the distal perforator closer to the medial epicondyle. The DBAp flap was used to reconstruct complex digit defects as free flap, and to cover an elbow defect while raised as a propeller. METHODS: Four patients underwent finger reconstruction (free flaps): two patients presented an unstable finger scar following previous surgery, whereas the other two patients presented a terminalized finger at the level of the middle phalanx. A further patient presented a post-traumatic loss of substance at the elbow and was reconstructed using a perforator propeller DBAP flap. RESULTS: Loss of tissues included skin and subcutaneous tissue in all patients and in one patient it included a bone component. Flap dimensions ranged from 48 to 18 cm2 (average: 32 cm2). Among complications, patient n.2 flap presented a marginal flap necrosis requiring a small skin graft after necrosis debridement. CONCLUSION: The DBAp flap provides a slim, glabrous and pliable skin tissue with a well-hidden donor site scar and thanks to the anatomic location of the distal perforator can be designed to include a vascularized bone graft from the medial epicondyle. Despite the low number of cases, we believe that this flap should be considered as a dependable and effective source for complex reconstructions of both soft tissue and bone in fingers.


Asunto(s)
Colgajo Perforante , Procedimientos de Cirugía Plástica , Traumatismos de los Tejidos Blandos , Arteria Braquial/cirugía , Cicatriz/cirugía , Humanos , Necrosis , Colgajo Perforante/irrigación sanguínea , Procedimientos de Cirugía Plástica/métodos , Trasplante de Piel/métodos , Traumatismos de los Tejidos Blandos/cirugía , Resultado del Tratamiento , Extremidad Superior/cirugía
9.
J Exp Med ; 180(2): 607-14, 1994 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8046336

RESUMEN

Human interleukin 1 beta (IL-1 beta) is synthesized as an inactive precursor that is cleaved by IL-1 converting enzyme (ICE) between Asp116 and Ala117 to form COOH-terminal mature IL-1 beta and NH2-terminal IL-1 beta propeptide. Little is known about the fate of the NH2-terminal cleavage product. In this study, human recombinant (hr)IL-1 beta propeptide (amino acids 2-116) was produced and used to prepare specific antibodies which do not recognize mature human IL-1 beta. These anti-propeptide antibodies were used for immunoprecipitation of biosynthetically labeled proteins from lipopolysaccharide-stimulated human monocytes. Analysis of immunoprecipitates by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fluorography revealed that these antibodies recognize precursor IL-1 beta and two unique proteins: one migrating at 17.5 kD and one at 14 kD. The larger of these two proteins has a migration nearly identical to that of the recombinant IL-1 beta propeptide, and most likely represents naturally derived propeptide. The protein migrating at 14 kD may result from a second cleavage by ICE, between Asp27 and Gly28. These proteins accumulate intracellularly and extracellularly during pulse-chase experiments, and therefore represent stable products of precursor IL-1 beta cleavage.


Asunto(s)
Interleucina-1/metabolismo , Lipopolisacáridos/inmunología , Monocitos/inmunología , Especificidad de Anticuerpos , Secuencia de Bases , Unión Competitiva , Western Blotting , Cromatografía de Afinidad , ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Datos de Secuencia Molecular , Monocitos/metabolismo , Pruebas de Precipitina , Precursores de Proteínas/metabolismo , Proteínas Recombinantes/inmunología
10.
Lupus ; 19(11): 1315-25, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20861207

RESUMEN

As part of the Atherosclerosis Prevention in Pediatric Lupus Erythematosus (APPLE) Trial, a prospective multicenter cohort of 221 children and adolescents with systemic lupus erythematosus (SLE) (mean age 15.7 years, 83% female) underwent baseline measurement of markers of cardiovascular risk, including fasting levels of high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), lipoprotein A (Lpa), homocysteine and high-sensitivity C-reactive protein (hs-CRP). A cross-sectional analysis of the baseline laboratory values and clinical characteristics of this cohort was performed. Univariable relationships between the cardiovascular markers of interest and clinical variables were assessed, followed by multivariable linear regression modeling. Mean levels of LDL, HDL, Lpa, TG, hs-CRP and homocysteine were in the normal or borderline ranges. In multivariable analysis, increased Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), prednisone dose, and hypertension (HTN) were independently associated with higher LDL levels. Higher hs-CRP and creatinine clearance were independently related to lower HDL levels. Higher body mass index (BMI), prednisone dose, and homocysteine levels were independently associated with higher TG levels. Only Hispanic or non-White status predicted higher Lpa levels. Proteinuria, higher TG and lower creatinine clearance were independently associated with higher homocysteine levels, while use of multivitamin with folate predicted lower homocysteine levels. Higher BMI, lower HDL, and longer SLE disease duration, but not SLEDAI, were independently associated with higher hs-CRP levels. The R(2) for these models ranged from 7% to 23%. SLE disease activity as measured by the SLEDAI was associated only with higher LDL levels and not with hs-CRP. Markers of renal injury (HTN, proteinuria, and creatinine clearance) were independently associated with levels of LDL, HDL, and homocysteine, highlighting the importance of renal status in the cardiovascular health of children and adolescents with SLE. Future longitudinal analysis of the APPLE cohort is needed to further examine these relationships.


Asunto(s)
Biomarcadores/sangre , Enfermedades Cardiovasculares , Lupus Eritematoso Sistémico , Adolescente , Proteína C-Reactiva/metabolismo , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Niño , Colesterol/sangre , Estudios Transversales , Método Doble Ciego , Femenino , Humanos , Lipoproteína(a)/sangre , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/complicaciones , Placebos , Factores de Riesgo , Triglicéridos/sangre , Adulto Joven
11.
JPRAS Open ; 24: 7-11, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32258334

RESUMEN

Obstetric brachial plexus injury is reported in 0.42 per 1000 births in UK and Ireland and are associated with a reduction in quality of life for the patient and their carers. In this report we describe the first use of a patient specific, anatomically accurate 3D model as a communication tool in the treatment of a complex case of posterior shoulder subluxation secondary to glenohumeral deformity resulting from obstetric brachial plexus injury. The use of 3D models for surgical planning is associated with decreased operating time and reduction of intra-operative blood loss, whilst their use in patient education increases patient understanding. In this case all surgeons surveyed agreed that it was useful and will use 3D modelling to improve consent processes and to conceptualise novel techniques for complex cases in future. This highly reproducible, low cost technique may be adapted to a variety of upper limb reconstructive surgeries, and as the resolution of image acquisition and additive manufacturing capabilities increase so too do the potential applications of this precise 3D printed surgical adjunct.

12.
J Cell Biol ; 109(6 Pt 1): 3039-52, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2592413

RESUMEN

cDNA clones of a neuronal-specific mRNA encoding a novel 25-kD synaptosomal protein, SNAP-25, that is widely, but differentially expressed by diverse neuronal subpopulations of the mammalian nervous system have been isolated and characterized. The sequence of the SNAP-25 cDNA revealed a single open reading frame that encodes a primary translation product of 206 amino acids. Antisera elicited against a 12-amino acid peptide, corresponding to the carboxy-terminal residues of the predicted polypeptide sequence, recognized a single 25-kD protein that is associated with synaptosomal fractions of hippocampal preparations. The SNAP-25 polypeptide remains associated with synaptosomal membrane components after hypoosmotic lysis and is released by nonionic detergent but not high salt extraction. Although the SNAP-25 polypeptide lacks a hydrophobic stretch of residues compatible with a transmembrane region, the amino terminus may form an amphiphilic helix that may facilitate alignment with membranes. The predicted amino acid sequence also includes a cluster of four closely spaced cysteine residues, similar to the metal binding domains of some metalloproteins, suggesting that the SNAP-25 polypeptide may have the potential to coordinately bind metal ions. Consistent with the protein fractionation, light and electron microscopic immunocytochemistry indicated that SNAP-25 is located within the presynaptic terminals of hippocampal mossy fibers and the inner molecular layer of the dentate gyrus. The mRNA was found to be enriched within neurons of the neocortex, hippocampus, piriform cortex, anterior thalamic nuclei, pontine nuclei, and granule cells of the cerebellum. The distribution of the SNAP-25 mRNA and the association of the protein with presynaptic elements suggest that SNAP-25 may play an important role in the synaptic function of specific neuronal systems.


Asunto(s)
Hipocampo/metabolismo , Proteínas de la Membrana , Proteínas del Tejido Nervioso/genética , Neuronas/metabolismo , Sinaptosomas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN/genética , Expresión Génica , Biblioteca de Genes , Inmunohistoquímica , Sistemas de Información , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Peso Molecular , Sondas de Oligonucleótidos , Biosíntesis de Proteínas , ARN Mensajero/análisis , ARN Mensajero/genética , Mapeo Restrictivo , Homología de Secuencia de Ácido Nucleico , Proteína 25 Asociada a Sinaptosomas
13.
Science ; 156(3776): 819-20, 1967 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-17780301

RESUMEN

Cliftonite, a polycrystalline aggregate of graphite with cubic morphology, is known in ten meteorites. Some workers have considered it to be a pseudomorph after diamond, and have used the proposed diamond ancestry as evidence of a meteoritic parent body of at least lunar dimensions.We have synthesized cliftonite in Fe-Ni-C alloys in vacuumn, as a product of decomposition of cohenite [(Fe, Ni)(3)C]. We therefore suggest that a high pressure origin is unnecessary for meteorites which contain cliftonite, and that these meteorites were formed at low pressures. This concluision is in agreement with other recent evidence.

14.
Science ; 237(4810): 77-80, 1987 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-3299701

RESUMEN

The distribution of cells containing messenger RNA that encodes amyloid beta protein was determined in hippocampi and in various cortical regions from cynomolgus monkeys, normal humans, and patients with Alzheimer's disease by in situ hybridization. Both 35S-labeled RNA antisense and sense probes to amyloid beta protein messenger RNA were used to ensure specific hybridization. Messenger RNA for amyloid beta protein was expressed in a subset of neurons in the prefrontal cortex from monkeys, normal humans, and patients with Alzheimer's disease. This messenger RNA was also present in the neurons of all the hippocampal fields from monkeys, normal humans and, although to a lesser extent in cornu ammonis 1, patients with Alzheimer's disease. The distribution of amyloid beta protein messenger RNA was similar to that of the neurofibrillary tangles of Alzheimer's disease in some regions, but the messenger RNA was also expressed in other neurons that are not usually involved in the pathology of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/genética , Amiloide/genética , Encéfalo/fisiopatología , Péptidos beta-Amiloides , Animales , Corteza Cerebral/fisiología , Regulación de la Expresión Génica , Hipocampo/fisiología , Humanos , Macaca fascicularis , Hibridación de Ácido Nucleico , ARN Mensajero/genética
15.
Neuron ; 5(3): 329-38, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2400606

RESUMEN

The deposition of cerebrovascular and plaque amyloid in the CNS is a primary feature of Alzheimer's disease and aged Down's syndrome pathology. The localization of the Alzheimer amyloid protein precursor (APP) gene on chromosome 21, along with its overexpression in Down's syndrome brain compared with normal brain, suggests that alterations in APP gene expression may play a role in the development of the neuropathology common to the two diseases. In the present report, we demonstrate that a specific spliced form of mRNA that is transcribed from the APP gene and that lacks the beta/A4 sequence is elevated in the nucleus basalis, occipitotemporal cortex, and parahippocampal gyrus in Alzheimer's disease brain relative to controls. These results are based on combined data from RNA slot blot analysis, in situ hybridization, and polymerase chain reaction quantification of specific mRNAs taken directly from tissue sections.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Amiloide/genética , Encéfalo/metabolismo , Precursores de Proteínas/genética , Transcripción Genética , Anciano , Anciano de 80 o más Años , Amiloide/metabolismo , Secuencia de Bases , Humanos , Persona de Mediana Edad , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Precursores de Proteínas/metabolismo , Empalme del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Distribución Tisular
16.
Neuron ; 3(2): 247-56, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2560393

RESUMEN

Chronic infusion of nerve growth factor (NGF) into the forebrain of the adult rat produced increases in NGF receptor (NGF-R) mRNA hybridization, NGF-R immunoreactivity, choline acetyltransferase (ChAT) mRNA hybridization, and neuronal hypertrophy, when compared with vehicle infusion or noninfused rat brain. In situ hybridization showed NGF induction of NGF-R gene expression, documented by increases in the number of NGF-R mRNA-positive cells within the medial septum, diagonal band, and nucleus basalis magnocellularis. NGF also produced hypertrophy of ChAT mRNA-positive neurons. These results suggest that NGF produces cholinergic neuronal hypertrophy through induction of NGF-R gene expression within the basal forebrain.


Asunto(s)
Encéfalo/efectos de los fármacos , Fibras Colinérgicas/patología , Factores de Crecimiento Nervioso/farmacología , Neuronas/patología , Receptores de Superficie Celular/genética , Animales , Encéfalo/metabolismo , Encéfalo/patología , Colina O-Acetiltransferasa/genética , Colina O-Acetiltransferasa/metabolismo , Fibras Colinérgicas/efectos de los fármacos , Fibras Colinérgicas/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Hipertrofia/inducido químicamente , Hipertrofia/patología , Inmunohistoquímica , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Hibridación de Ácido Nucleico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Endogámicas , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Factor de Crecimiento Nervioso
17.
Neuron ; 6(3): 371-80, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1672072

RESUMEN

A combination of gene transfer and intracerebral grafting may provide a powerful technique for examining the role of discrete substances in the development or functioning of the brain. In the present study, primary fibroblasts obtained from a skin biopsy from inbred Fischer rats were used as donor cells for genetic modification and grafting. When grafted to the striatum of Fischer rats with a prior 6-hydroxydopamine lesion, primary fibroblasts containing a transgene for either tyrosine hydroxylase (TH) or beta-galactosidase survived for 10 weeks and continued to express the transgene. TH synthesized by the implanted fibroblasts appeared to convert tyrosine to L-dopa actively, as observed in vitro, and to affect the host brain, as assessed through a behavioral measurement. These results suggest that primary fibroblasts genetically altered to express TH have the capacity to deliver L-dopa locally to the striatum in quantities sufficient to compensate partially for the loss of intrinsic striatal dopaminergic input.


Asunto(s)
Fibroblastos/citología , Levodopa/metabolismo , Animales , Supervivencia Celular/fisiología , Fibroblastos/metabolismo , Fibroblastos/fisiología , Ratas , Ratas Endogámicas F344 , Piel/citología , Trasplante de Piel/fisiología , Transfección , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
18.
Neuron ; 2(2): 1177-84, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2576209

RESUMEN

Adult cholinergic interneurons of the neostriatum are not immunoreactive for monoclonal antibody to NGF receptor, whereas the developing neostriatum is immunoreactive for this same antibody. Chronic NGF infusion into the adult neostriatum resulted in reexpression of the NGF receptor such that many cholinergic interneurons became immunoreactive for NGF receptor. NGF infusion dramatically increased the size and choline acetyltransferase immunoreactivity of these same cholinergic neurons. Additionally, in situ hybridization demonstrated an increase in the number of cells expressing NGF receptor mRNA in the NGF-infused striatum. These findings indicate that central cholinergic neurons which lose their NGF receptors during postnatal development will resume their NGF responsiveness when the tissue is damaged. Such a damage-induced mechanism may act to enhance the action of trophic factors, including NGF, released at the site of injury and enhance the responsiveness of damaged CNS neurons to exogenously administered trophic factors.


Asunto(s)
Colina O-Acetiltransferasa/metabolismo , Cuerpo Estriado/metabolismo , Expresión Génica/efectos de los fármacos , Factores de Crecimiento Nervioso/farmacología , Neuronas/metabolismo , Receptores de Superficie Celular/genética , Envejecimiento , Animales , Anticuerpos Monoclonales , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/crecimiento & desarrollo , Femenino , Proteína Ácida Fibrilar de la Glía/análisis , Factores de Crecimiento Nervioso/metabolismo , Neuronas/efectos de los fármacos , ARN Mensajero/genética , Ratas , Ratas Endogámicas , Receptores de Factor de Crecimiento Nervioso , Valores de Referencia , Tirosina 3-Monooxigenasa/metabolismo
19.
Biosens Bioelectron ; 23(7): 1161-5, 2008 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-18054481

RESUMEN

This report describes the fabrication and successful use of the ion channel switch biosensor (ICSB) for rapid point-of-care detection of influenza A in different types of respiratory specimens. Virus culture -- regarded as the "gold standard" -- and an immunochromatographic rapid point-of-care test for influenza A virus were compared with the biosensor. The ICSB rapid test provided an objective readout within 10 min of specimen inoculation into the ICSB chamber wells, without the need for chemical or other pretreatments. Construction of the ICSB with specific antibodies also enables rapid detection and identification of appropriate influenza A subtypes.


Asunto(s)
Técnicas Biosensibles/instrumentación , Inmunoensayo/instrumentación , Virus de la Influenza A/aislamiento & purificación , Carga Viral/instrumentación , Técnicas Biosensibles/métodos , Sistemas de Computación , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Inmunoensayo/métodos , Iones , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Carga Viral/métodos
20.
Bone ; 40(3): 730-6, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17141597

RESUMEN

We studied the association between plasma total homocysteine (tHcy), its determinants folate, vitamin B(12), vitamin B(6) and MTHFR genotype, and bone mineral density (BMD) in 328 postmenopausal British women. When the subjects were assigned to one of 3 groups (control, osteopenic or osteoporotic) according to their BMD at the os calcis, those in the osteoporotic group had, compared with the controls, a significantly lower serum folate concentration, a significantly higher % of current smokers and a significantly higher incidence of recent fracture. In the population as a whole, we found significant associations of BMD with tHcy (r=-0.130, p=0.033, log tHcy) and folate (r=0.132, p=0.025, log folate). The association of folate with BMD was maintained after correction for age, weight and height (r=0.124, p=0.042, log folate), but the association of tHcy with BMD weakened after correction for age, weight, height and creatinine (r=-0.117, p=0.059, log tHcy). Vitamins B(12) and B(6) were not associated with BMD, but were significantly associated with tHcy, vitamin B(12) (r=-0.34, p<0.0001), vitamin B(6) (r=-0.16, p=0.007), as was folate (r=-0.41, p<0.0001). There was an increasing frequency of the MTHFR TT genotype across the 3 BMD groups, but this did not attain significance. Individuals with the TT genotype had significantly higher plasma tHcy but there was no difference between the genotypes (CC, CT, TT) for folate or BMD. Smoking was associated with a highly significant reduction in BMD and lower weight, and a significant reduction in circulating folate and vitamin B(6) concentrations, but no change in tHcy or vitamin B(12) concentrations when compared with non-smokers. We conclude that low serum folate is a significant risk factor for osteoporosis, with plasma tHcy having a lesser effect. Both vitamins B(12) and B(6), by acting through tHcy, may also have an effect on the skeleton, albeit a weaker one than folate. Cigarette smoking is a strong determinant of BMD, and may act through effects on folate and vitamin B(6).


Asunto(s)
Densidad Ósea/fisiología , Homocisteína/sangre , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Osteoporosis Posmenopáusica/etiología , Vitamina B 12/sangre , Vitamina B 6/sangre , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Metilenotetrahidrofolato Reductasa (NADPH2)/sangre , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/genética , Polimorfismo Genético , Posmenopausia/fisiología , Fumar/efectos adversos , Población Blanca/genética
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