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1.
Cogn Emot ; 37(4): 748-762, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37104122

RESUMEN

Recognising and responding appropriately to emotions is critical to adaptive psychological functioning. Psychopathic traits (e.g. callous, manipulative, impulsive, antisocial) are related to differences in recognition and response when emotion is conveyed through facial expressions and language. Use of emotional music stimuli represents a promising approach to improve our understanding of the specific emotion processing difficulties underlying psychopathic traits because it decouples recognition of emotion from cues directly conveyed by other people (e.g. facial signals). In Experiment 1, participants listened to clips of emotional music and identified the emotional content (Sample 1, N = 196) or reported on their feelings elicited by the music (Sample 2, N = 197). Participants accurately recognised (t(195) = 32.78, p < .001, d = 4.69) and reported feelings consistent with (t(196) = 7.84, p < .001, d = 1.12) the emotion conveyed in the music. However, psychopathic traits were associated with reduced emotion recognition accuracy (F(1, 191) = 19.39, p < .001) and reduced likelihood of feeling the emotion (F(1, 193) = 35.45, p < .001), particularly for fearful music. In Experiment 2, we replicated findings for broad difficulties with emotion recognition (Sample 3, N = 179) and emotional resonance (Sample 4, N = 199) associated with psychopathic traits. Results offer new insight into emotion recognition and response difficulties that are associated with psychopathic traits.


Asunto(s)
Música , Humanos , Trastorno de Personalidad Antisocial/psicología , Emociones/fisiología , Miedo , Expresión Facial
2.
Eur Cell Mater ; 42: 438-451, 2021 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-34846723

RESUMEN

Vertebral osteomyelitis (VO) is an infection of the spine mainly caused by bacterial pathogens. The pathogenesis leading to destruction of intervertebral discs (IVDs) and adjacent vertebral bodies (VBs) is poorly described. The present study aimed at investigating the connection between infection and bone/disc metabolism in VO patients. 14 patients with VO (infection group) and 14 patients with burst fractures of the spine (fracture group; control) were included prospectively. Tissue biopsies from affected IVDs and adjacent VBs were analysed by RT-qPCR for mRNA-expression levels of 18 target genes including chemokines, adipokines and genes involved in bone metabolism. Most importantly, the receptor activator of NF-κB/osteoprotegerin (RANK/OPG) expression ratio was drastically elevated in both VBs and IVDs of the infection group. In parallel, expression of genes of the prostaglandin-E2-dependent prostanoid system was induced. Such genes regulate tissue degradation processes via the triad OPG/RANK/RANKL as well as via the chemokines IL-8 and CCL-20, whose expression was also found to be increased upon infection. The gene expression of the adipokine leptin, which promotes inflammatory tissue degradation, was higher in IVD tissue of the infection group, whereas the transcription of omentin and resistin genes, whose functions are largely unknown in the context of infectious diseases, was lower in infected VBs. In summary, similar expression patterns of pro-inflammatory cytokines and pro-osteoclastogenic factors were identified in VBs and IVDs of patients suffering from VO. This suggests that common immuno-metabolic pathways are involved in the mechanisms leading to tissue degradation in VBs and IVDs during VO.


Asunto(s)
Disco Intervertebral , Osteomielitis , Humanos , Osteoprotegerina , Ligando RANK , Receptor Activador del Factor Nuclear kappa-B/genética , Cuerpo Vertebral
3.
Phys Chem Chem Phys ; 22(24): 13418-13430, 2020 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-32515438

RESUMEN

The elementary steps of photocleavage in (coumarin-4-yl)methyl photoremovable protecting groups (PPGs) are elucidated by a combined electronic structure and time-resolved visible pump infrared probe (VIS-pump IR-probe) spectroscopic study. We specifically focus on the [7-(diethylamino)coumarin-4-yl]methyl (DEACM) PPG which has found increasing interest in biological applications over recent years. A series of leaving groups (LGs) are investigated, including azide (DEACM-N3), thiocyanate (DEACM-SCN), carbonate (DEACM-Carb), and a thymine nucleobase (DEACM-T) representing a model system for caged DNA. These systems are found to exhibit vastly different photocleavage time scales, ranging from the subpicosecond scale in the case of DEACM-SCN to ∼35 picoseconds in the case of DEACM-N3 and ∼540 picoseconds in the case of DEACM-Carb. In the case of DEACM-SCN, the appearance of the product is biphasic, with a fast (

4.
Klin Monbl Augenheilkd ; 235(8): 898-904, 2018 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-28470654

RESUMEN

BACKGROUND: Tumors of the lacrimal duct are rare. Inflammatory pseudotumors do not represent neoplasias as such. Chronic inflammation may lead to an angiomatous granulation tissue. PATIENTS: The first case presents a 53-year-old male patient suffering a mass of the mediocaudal orbit after an acute dacryocystitis has been cured. Using diagnostic dacryoendoscopy, a large dacryolith was detected. Removing the concrement, via external dacryocystorhinostomy, a polypous tissue appeared which was resected as well. The second case concerns a 29-year-old female patient. She had a lacrimal surgery with stenting seven years prior to surgery. The patient's history revealed recurrent mucous secretion of the tear duct and tenderness of the lacrimal sac. An intrasaccal silicon foreign body could be confirmed by dacryoendoscopy. An external dacryocystorhinostomy was performed and the material was extracted. Hereby, an inflammatory tissue mass filling the whole efferent tear duct was removed. RESULTS: In both patients, external dacryocystorhinostomy was performed complication-free. Surgery enabled the reconstruction of the nasolacrimal duct. Temporary autostable silicon intubation was inserted into the nasolacrimal duct (case 1 and 2), as well into osteotomy (case 2). Histologically, reactive granulation tissue was confirmed. During the follow-up of 9 months (patient 1) and 12 months (patient 2), patients were free of complaints. Lacrimal stentings were removed uneventfully and completely. CONCLUSIONS: Dacryoliths and intrasaccal foreign bodies may cause a chronic dacryocystitis. Due to inflammation, reactive tissue proliferation can be initiated. In these cases, a hypertrophic granulation arose. Endogenous (dacryoliths) and exogenous (iatrogenic foreign bodies) triggers may be underlying reasons. Histological examination is essential for differentiating other inflammatory pathologies or tumors.


Asunto(s)
Dacriocistitis , Dacriocistorrinostomía , Cuerpos Extraños , Granuloma de Células Plasmáticas , Obstrucción del Conducto Lagrimal , Conducto Nasolagrimal , Adulto , Femenino , Humanos , Enfermedad Iatrogénica , Masculino , Persona de Mediana Edad , Órbita
5.
Phys Chem Chem Phys ; 19(9): 6487-6496, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28197598

RESUMEN

The light-induced ultrafast uncaging process of the [7-(diethylamino)coumarin-4-yl]methyl (DEACM) cage is measured by time-resolved visible-pump-infrared-probe spectroscopy, and supported by steady-state absorption spectroscopy in the visible and infrared spectral regions. Understanding the uncaging process is important because its favorable properties make DEACM an interesting case for chemical and biological applications. It has a convenient absorption in the visible spectral range, and is relatively easily modified to carry leaving groups (LGs) such as nucleotides, substrates or inhibitors, which are inactive when bound and active when released. Previous work suggested a lower limit for the uncaging rate, which places it among the fastest available cages. Here, we determine the photodissociation directly to occur on the picosecond time scale by monitoring the appearance of the released LG in the infrared spectral region. In the present study, azide (N3) is chosen as an LG to monitor photodissociation because its vibrational mode is spectrally isolated (hence easy to follow) and its absorption wavenumber is sensitive to local structural rearrangements. The uncaging process is recorded up to 3 nanoseconds and compared to the collected steady-state spectra. The free LG appears on a picosecond time scale, rendering this one of the fastest known cages. No evidence is found for a tight-ion pair (TIP) preceding the free LG. The uncaging mechanism is found to be slowed down upon the addition of water to acetonitrile.

6.
Hum Brain Mapp ; 37(11): 4047-4060, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27342447

RESUMEN

The uncompetitive NMDA receptor antagonist ketamine has been proposed to model symptoms of psychosis. Smooth pursuit eye movements (SPEM) are an established biomarker of schizophrenia. SPEM performance has been shown to be impaired in the schizophrenia spectrum and during ketamine administration in healthy volunteers. However, the neural mechanisms mediating SPEM impairments during ketamine administration are unknown. In a counter-balanced, placebo-controlled, double-blind, within-subjects design, 27 healthy participants received intravenous racemic ketamine (100 ng/mL target plasma concentration) on one of two assessment days and placebo (intravenous saline) on the other. Participants performed a block-design SPEM task during functional magnetic resonance imaging (fMRI) at 3 Tesla field strength. Self-ratings of psychosis-like experiences were obtained using the Psychotomimetic States Inventory (PSI). Ketamine administration induced psychosis-like symptoms, during ketamine infusion, participants showed increased ratings on the PSI dimensions cognitive disorganization, delusional thinking, perceptual distortion and mania. Ketamine led to robust deficits in SPEM performance, which were accompanied by reduced blood oxygen level dependent (BOLD) signal in the SPEM network including primary visual cortex, area V5 and the right frontal eye field (FEF), compared to placebo. A measure of connectivity with V5 and FEF as seed regions, however, was not significantly affected by ketamine. These results are similar to the deviations found in schizophrenia patients. Our findings support the role of glutamate dysfunction in impaired smooth pursuit performance and the use of ketamine as a pharmacological model of psychosis, especially when combined with oculomotor biomarkers. Hum Brain Mapp 37:4047-4060, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Antagonistas de Aminoácidos Excitadores/farmacología , Ketamina/farmacología , Seguimiento Ocular Uniforme/fisiología , Adulto , Atención/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Circulación Cerebrovascular/efectos de los fármacos , Circulación Cerebrovascular/fisiología , Método Doble Ciego , Antagonistas de Aminoácidos Excitadores/sangre , Medidas del Movimiento Ocular , Humanos , Ketamina/sangre , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Oxígeno/sangre , Psicosis Inducidas por Sustancias/fisiopatología , Psicosis Inducidas por Sustancias/psicología , Seguimiento Ocular Uniforme/efectos de los fármacos , Movimientos Sacádicos/efectos de los fármacos , Movimientos Sacádicos/fisiología , Encuestas y Cuestionarios
7.
Phys Chem Chem Phys ; 18(12): 8662-72, 2016 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-26948995

RESUMEN

The photochemistry of p-bromophenylsulfonyl azide (BsN3), p-tolylsulfonyl azide (TsN3) and methylsulfonyl azide (MsN3) was studied by femtosecond time-resolved infrared spectroscopy with CH2Cl2 and CCl4 as solvents along with quantum chemical calculations. The photolysis of these azides after 267 nm light excitation leads to the population of each respective azide S1 excited state. Decay of the S1 excited state gives rise to singlet nitrene formation. In the case of BsN3, the decay was found to correlate with the formation of a pseudo-Curtius photoproduct (PCP) BrC6H4NSO2. Transient electronic ground states of the three azides on their way to singlet nitrenes and PCPs were shown by locating the corresponding transition states on the potential energy surfaces. The lifetime of singlet (1)(BsN) and (1)(TsN) nitrenes is τ(S) = ∼20 ps in CH2Cl2 and ∼700 ps in CCl4. Singlet (1)(MsN) was not detected. Due to fast intersystem crossing (ISC), singlet nitrenes are converted into the triplet spin isomers lying lower in energy, the formation time constants being equal to the corresponding singlet nitrene lifetime. The formation of (3)(MsN) was shown and the formation time constant in CH2Cl2 was found to be τ(ISC) = 34 ± 3 ps. Internal conversion of the S1 excited state to the ground state of the azide was low (Φ ≈ 0.15) for BsN3 and TsN3 and was not found in the case of MsN3.

8.
Unfallchirurg ; 119(11): 901-907, 2016 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-27770166

RESUMEN

BACKGROUND: New regulations of the German statutory accident insurance for inpatient treatment have been introduced. The aims of the new regulations are to improve cost-effectiveness and the quality of medical care. The introduction of the injury type catalogue and the severe injuries type procedure (SAV) has led to a concentration of resources. The purpose of these innovations is an increase in the quality of treatment of patients with complex injuries. CONCLUSION: The introduction of the new regulations resulted in a centralization of medical care in order to optimize the quality of treatment of complex injuries from occupational accidents. Hence, the high demands concerning infrastructure and human resources expected of a level one university medical center are taken into account.


Asunto(s)
Centros Médicos Académicos/legislación & jurisprudencia , Centros Médicos Académicos/estadística & datos numéricos , Seguro por Accidentes/legislación & jurisprudencia , Programas Nacionales de Salud/legislación & jurisprudencia , Medicina del Trabajo/legislación & jurisprudencia , Heridas y Lesiones/terapia , Alemania , Regulación Gubernamental , Humanos , Seguro por Accidentes/economía , Seguro por Accidentes/normas , Programas Nacionales de Salud/economía , Programas Nacionales de Salud/normas , Medicina del Trabajo/economía , Medicina del Trabajo/normas , Heridas y Lesiones/economía
9.
Br J Cancer ; 112(9): 1461-70, 2015 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-25880007

RESUMEN

BACKGROUND: The mechanisms by which stress hormones impact triple-negative breast cancer (TNBC) etiology and treatment are unclear. We have previously shown that stress hormones, cortisol, and catecholamines induce rapid DNA damage and impact DNA repair in NIH 3T3 fibroblasts. This study investigates whether stress hormones increase DNA damage in breast cancer cells and if this impacts drug efficacy. METHODS: We first screened a panel of 39 breast cancer cell lines for expression of adrenergic and glucocorticoid receptors and examined if stress hormones induce DNA damage and alter cell cycle regulation in vitro. A TNBC xenograft model was used to assess the impact of restraint stress on tumour growth and chemosensitivity to paclitaxel. RESULTS: We found that stress hormones induced DNA damage, phosphorylation of ATR, which was accompanied by an up-regulation of the G1 cell kinase inhibitor p21 and a cell cycle halt of TNBCs in the G1 phase. p21 knockdown abrogated G1 arrest by stress hormones. We also demonstrated that stress significantly decreased efficacy of paclitaxel. CONCLUSION: We describe a novel mechanism through which stress hormones can induce drug resistance to paclitaxel, which may have profound implications for treating drug resistance in patients with TNBC.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Catecolaminas/farmacología , Daño del ADN/efectos de los fármacos , Hidrocortisona/farmacología , Paclitaxel/farmacología , Estrés Fisiológico/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/patología , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Reparación del ADN/efectos de los fármacos , Femenino , Citometría de Flujo , Humanos , Ratones , Ratones Desnudos , Receptores de Estrógenos/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Haemophilia ; 21(4): 481-9, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25817556

RESUMEN

Factor XI (FXI)-deficient patients may develop excessive bleeding after trauma or surgery. Replacement therapy should be considered in high-risk situations, especially when FXI levels are below 20 IU dL(-1) . HEMOLEVEN is a human plasma-derived factor XI concentrate available in France since 1992, but there are few data regarding its use by physicians. This prospective study assessed the use, efficacy and safety of HEMOLEVEN in common clinical practice. HEMOLEVEN was evaluated in FXI-deficient patients in 13 French centres in a 3-year postmarketing study. Forty-four patients (30 females, 14 males) received 67 treatments. The median age was 37 years (8 months-91 years). Basal FXI levels were <1 to 51 IU dL(-1) (median: 5.5); 29 patients were severely FXI-deficient (<20 IU dL(-1) ). FXI was administered prophylactically before 43 surgical procedures, 10 invasive procedures, 8 vaginal deliveries, or as curative treatment for six bleeds. The efficacy was assessed as excellent/good in 63, moderate in two and undetermined in two treatments. Seven patients experienced seven adverse effects, including two rated as serious: one sudden massive pulmonary embolism with fatal outcome and one case of inhibitor to FXI. HEMOLEVEN is effective for bleeding prevention in FXI deficiency. However, considering the benefit/risk ratio observed in relation to dosage in this study; firstly, it should be used sparingly due to its potential prothrombotic effect; secondly, new prescription procedures should be defined to adapt the dosage, especially in patients with intrinsic and/or acquired risk factors for thrombosis.


Asunto(s)
Deficiencia del Factor XI/tratamiento farmacológico , Factor XI/uso terapéutico , Trombosis/etiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pérdida de Sangre Quirúrgica/prevención & control , Niño , Preescolar , Factor XI/efectos adversos , Factor XI/inmunología , Femenino , Hemostasis Quirúrgica , Humanos , Lactante , Masculino , Persona de Mediana Edad , Vigilancia de Productos Comercializados , Estudios Prospectivos , Factores de Riesgo , Adulto Joven
11.
Acta Chir Orthop Traumatol Cech ; 82(2): 119-25, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26317180

RESUMEN

UNLABELLED: INTRODUCTION Alternative fusion expanders are in clinical use for instrumented posterolateral fusion (PLF) to avoid donor site morbidity in autologous bone graft (ABG) harvesting. Purpose of this study was to evaluate demineralized bone matrix (DBM) in PLF as alternative to the gold standard of ABG in acute traumatic vertebral body fractures of the thoracolumbar spine. MATERIAL AND METHODS We retrospectively identified 101 patients with acute traumatic vertebral body fractures of the thoracic and lumbar spine who were treated with instrumented PLF in our level one trauma center between 2005 and 2011. Patients with a primary paraplegia, osteodepriving disease or loss to follow-up had been excluded. Until August 2008, autologous bone graft harvested from the posterior iliac crest was used in PLF (control group n = 46). Starting September 2008, DBM was used as fusion expander in PLF (study group n = 16). Clinical and radiological evaluation was performed with a minimum followup of 18 months to assess the clinical and radiological outcome. RESULTS We found a fusion rate of 94% in patients undergoing PLF with the use of DBM and 100% with the use of ABG. There was one major complication of deep infection in the DBM group and two cases of superficial wound infection in the ABG group. We discovered a trend of reduced operating time with the use of DBM. CONCLUSIONS DBM leads to a similar fusion rate as the use of ABG in patients undergoing PLF for acute traumatic vertebral body fractures of the thoracic and lumbar spine. DBM is associated with reduced operating time. LEVEL OF EVIDENCE III: case-control study Key words: demineralized bone matrix instrumented posterolateral fusion, acute traumatic vertebral body fracture, thoracolumbar spine, autologous bone graft.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Matriz Ósea/trasplante , Ilion/trasplante , Vértebras Lumbares/cirugía , Fracturas de la Columna Vertebral/cirugía , Fusión Vertebral/métodos , Vértebras Torácicas/cirugía , Adulto , Estudios de Casos y Controles , Femenino , Curación de Fractura , Humanos , Vértebras Lumbares/lesiones , Masculino , Persona de Mediana Edad , Oseointegración , Estudios Retrospectivos , Vértebras Torácicas/lesiones , Trasplante Autólogo
12.
Infection ; 42(3): 503-10, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24446233

RESUMEN

PURPOSE: Vertebral osteomyelitis (VO) is an infection of the vertebral body and the adjacent disc space. The aim of our study was to identify outcome-related co-factors of patients with VO treated in the last decade. METHODS AND RESULTS: We retrospectively identified 105 patients with VO (mean age 66.1 years) who had been treated at our institution from 2004 to 2011. The median time of hospitalization at our institution was 31.5 days, and 44 patients required intensive medical care. Back pain and fever were documented in 66.7 and 33.3 % of cases, respectively. The radiologic diagnosis of VO was made in 94.8 % of all obtained magnetic resonance imaging scans and in 66.2 % of all computed tomography (CT) scans. Biopsies were taken in 71 patients, and the causative organisms were identified in 56.2 % of patients, with Staphylococcus aureus being the predominant pathogen. Fifty-six patients underwent surgical treatment. During hospitalization, infectious complications were observed in 63 patients (60.0 %). The most common complications were psoas, paravertebral and epidural abscesses. Patients with S. aureus infections had a significantly higher rate of infectious complications than those without (76.5 vs. 40.3 %, respectively), and were more frequently treated in intensive care units (58.8 vs. 34.7 %, respectively). Overall in-hospital mortality rate was 12.4 %. Elevated C-reactive protein levels at admission, advanced age and a Charlson Comorbidity Index of ≥2 were associated with higher mortality. CONCLUSIONS: Magnetic resonance imaging currently is the imaging procedure of choice for the radiologic diagnosis of VO. Mortality is attributable in part to co-morbidities. However, infections with S. aureus are frequent in this patient population and are associated with a higher rate of complications and a trend towards higher mortality.


Asunto(s)
Antibacterianos/uso terapéutico , Desbridamiento , Osteomielitis/terapia , Espondilitis/terapia , Adulto , Anciano , Anciano de 80 o más Años , Cuidados Críticos/estadística & datos numéricos , Femenino , Humanos , Tiempo de Internación , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mortalidad , Osteomielitis/complicaciones , Osteomielitis/diagnóstico , Osteomielitis/patología , Radiografía , Estudios Retrospectivos , Columna Vertebral/diagnóstico por imagen , Espondilitis/complicaciones , Espondilitis/diagnóstico , Espondilitis/patología , Análisis de Supervivencia , Centros de Atención Terciaria , Resultado del Tratamiento
13.
HNO ; 62(7): 498-501, 2014 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-25056646

RESUMEN

Active implantable hearing devices were primarily developed for sensorineural hearing loss. The vibrator coupling mechanisms were oriented towards normal middle ear anatomy and function. The aim of this project was to modify the only fully implantable hearing device with an implantable microphone for application in congenital auricular atresia, Carina™, and to introduce the modified device into the clinic. A special prosthesis was developed for the transducer and its individual coupling achieved by a special cramping system. The system was implanted in 5 patients with congenital auricular atresia. Audiological results were good; with patients' hearing gain exceeding 30 dB HL. Anatomic limits to the system's indications and technical drawbacks are also discussed.


Asunto(s)
Conducción Ósea , Implantes Cocleares , Conducto Auditivo Externo/anomalías , Pérdida Auditiva Conductiva/congénito , Pérdida Auditiva Conductiva/rehabilitación , Sistemas Microelectromecánicos/instrumentación , Prótesis Osicular , Adolescente , Adulto , Anciano , Análisis de Falla de Equipo , Femenino , Pérdida Auditiva Conductiva/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Procesamiento de Señales Asistido por Computador/instrumentación , Espectrografía del Sonido/instrumentación , Transductores , Resultado del Tratamiento , Adulto Joven
15.
Nanotechnology ; 24(44): 444001, 2013 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-24113720

RESUMEN

We discuss graphene nanoribbon-based charge sensors and focus on their functionality in the presence of external magnetic fields and high frequency pulses applied to a nearby gate electrode. The charge detectors work well with in-plane magnetic fields of up to 7 T and pulse frequencies of up to 20 MHz. By analyzing the step height in the charge detector's current at individual charging events in a nearby quantum dot, we determine the ideal operation conditions with respect to the applied charge detector bias. Average charge sensitivities of 1.3 × 10(-3)e Hz(-1/2) can be achieved. Additionally, we investigate the back action of the charge detector current on the quantum transport through a nearby quantum dot. By varying the charge detector bias from 0 to 4.5 mV, we can increase the Coulomb peak currents measured at the quantum dot by a factor of around 400. Furthermore, we can completely lift the Coulomb blockade in the quantum dot.

16.
Nat Genet ; 23(1): 86-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10471505

RESUMEN

Recent large-scale mutagenesis screens have made the zebrafish the first vertebrate organism to allow a forward genetic approach to the discovery of developmental control genes. Mutations can be cloned positionally, or placed on a simple sequence length polymorphism (SSLP) map to match them with mapped candidate genes and expressed sequence tags (ESTs). To facilitate the mapping of candidate genes and to increase the density of markers available for positional cloning, we have created a radiation hybrid (RH) map of the zebrafish genome. This technique is based on somatic cell hybrid lines produced by fusion of lethally irradiated cells of the species of interest with a rodent cell line. Random fragments of the donor chromosomes are integrated into recipient chromosomes or retained as separate minichromosomes. The radiation-induced breakpoints can be used for mapping in a manner analogous to genetic mapping, but at higher resolution and without a need for polymorphism. Genome-wide maps exist for the human, based on three RH panels of different resolutions, as well as for the dog, rat and mouse. For our map of the zebrafish genome, we used an existing RH panel and 1,451 sequence tagged site (STS) markers, including SSLPs, cloned candidate genes and ESTs. Of these, 1,275 (87.9%) have significant linkage to at least one other marker. The fraction of ESTs with significant linkage, which can be used as an estimate of map coverage, is 81.9%. We found the average marker retention frequency to be 18.4%. One cR3000 is equivalent to 61 kb, resulting in a potential resolution of approximately 350 kb.


Asunto(s)
Genoma , Mapeo Físico de Cromosoma , Pez Cebra/genética , Animales , Mapeo Cromosómico , Electroforesis en Gel de Agar , Etiquetas de Secuencia Expresada , Marcadores Genéticos , Escala de Lod , Modelos Genéticos , Polimorfismo Genético , Lugares Marcados de Secuencia , Programas Informáticos
17.
J Environ Manage ; 127 Suppl: S15-23, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23254313

RESUMEN

In scope of an IWRM concept for the Federal District, Western Central Brazil we developed a planning support tool, which enables non-experts to test the effects of land-use and land-cover change (LULCC) on landscape processes and landscape functions (LPF) related to sediment generation and retention. For this purpose we developed the web-based tool Letsmap do Brasil. The tool has two principal layers. The upper layer contains information on land use and its effect on LPF, i.e. sediment retention, runoff control, nitrogen loss control and agronomic value. The parameterized relation between land use and LPF is the core of the whole system. For each LPF a value specific to land use has been assigned. A second layer contains information on landscape properties and potentials (LPP), e.g. potential for sediment input in river networks and runoff potential. By linking land use and LPPs the system provides a spatially explicit assessment of effects of LULCC on landscape processes and functions (LPF). Letsmap do Brasil might have two major purposes. (1) It will support decision-making in river basin management and sediment management. By creating their own land-use/cover pattern non-expert users are enabled to test effects of LULCC on LPFs. (2) It will support and train non-experts to participate in decision processes in land-use planning. Because of its high adaptability, transparency, and simple handling Letsmap do Brasil might be used as tool in river basin management and land-use planning.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Sedimentos Geológicos/análisis , Brasil , Monitoreo del Ambiente , Ríos
18.
East Afr Med J ; 90(3): 104-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26866109

RESUMEN

Clinical rickets has not been reported previously in Embu district, Kenya. Baseline clinical assessments performed for a nutrition intervention study in preschool children (n=324) identified 28 cases of rickets (8.6% of study sample). Clinical characteristics included: delays of sitting, walking, and teething; bone and chest deformities; widened wrists and ankles; and bowed lower extremities. Risk factors identified were short duration of breastfeeding with feeding of cereal-based supplements with little or no milk, low calcium intake, limited sunlight exposure. Vitamin D and calcium deficiencies likely contributed to these cases. Treatment with Vitamin D3 and milk resulted in clinical improvement.


Asunto(s)
Discapacidades del Desarrollo , Leche , Raquitismo , Vitamina D , Animales , Lactancia Materna , Calcio/metabolismo , Niño , Preescolar , Discapacidades del Desarrollo/etiología , Discapacidades del Desarrollo/prevención & control , Femenino , Humanos , Lactante , Masculino , Raquitismo/complicaciones , Raquitismo/diagnóstico , Raquitismo/metabolismo , Raquitismo/fisiopatología , Raquitismo/terapia , Factores de Riesgo , Resultado del Tratamiento , Vitamina D/metabolismo , Vitamina D/uso terapéutico , Vitaminas/uso terapéutico
19.
Kidney Blood Press Res ; 35(2): 71-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-21912181

RESUMEN

BACKGROUND/AIMS: Several polymorphisms of vasoactive hormones have been implicated in hypertension. Erythropoietin (EPO) interacts with vasoactive substances, such as angiotensin II. Previously detected single nucleotide polymorphisms in the hypoxia-responsive element of EPO might be associated with hypertension and hypertensive end organ damages. METHODS: 400 hypertensive patients and 200 age- and gender-matched normotensive controls were genotyped for an EPO polymorphism [cytosine (C)/thymine (T) single nucleotide polymorphism] at position 3434. Patients were grouped according to their genotype into the CC group (CC genotype) and the CT/TT group (CT and TT genotype). BP was measured by ambulatory BP monitoring. RESULTS: The CC genotype was present in 87% of hypertensive patients and in 78.5% of controls (p = 0.007). In addition, patients with the CC genotype had higher BP levels compared with CT/TT genotypes (BPsys 143.7 ± 20.4 vs. 136.1 ± 13.5 mm Hg, p = 0.01, and BPdias 85.8 ± 11.6 vs. 82.4 ± 8.9, p = 0.043) despite a nearly identical number of antihypertensive drugs (2.3 ± 1.5 vs. 2.3 ± 1.6; p = 0.257). 100% of the small number of patients with end-stage renal disease (n = 15) had the CC genotype. CONCLUSION: The CC genotype of the EPO gene at position 3434 is more frequently found in patients with hypertension and is associated with higher BP levels.


Asunto(s)
Presión Sanguínea/genética , Eritropoyetina/genética , Hipertensión Renal/genética , Hipoxia/genética , Polimorfismo Genético , Adulto , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Femenino , Genotipo , Homocigoto , Humanos , Hipertensión Renal/fisiopatología , Hipoxia/fisiopatología , Masculino , Persona de Mediana Edad , Infarto del Miocardio/genética , Infarto del Miocardio/fisiopatología , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/fisiopatología , Enfermedades Vasculares/genética , Enfermedades Vasculares/fisiopatología
20.
Clin Otolaryngol ; 37(1): 23-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22433135

RESUMEN

OBJECTIVE: The 'Sniffin' Sticks' olfactory test contains pen-like odour dispensing devices which are used to assess olfactory threshold, discrimination and identification. Odour identification is strongly dependent on familiarity with the odours and has an important cultural component which has limited the usefulness of other validated tests. The 'Sniffin' Sticks' test was developed in Germany and is validated in other countries but not in the UK. This study aims to validate the applicability of 'Sniffin' Sticks' in a local population. DESIGN: Prospective controlled study. SETTING: Rhinology or olfactory disorder clinic. PARTICIPANTS: About 82 subjects, 33 healthy volunteers with a reported normal sense of smell, and 49 patients with an impaired sense of smell presenting either at a rhinology or an olfactory disorder clinic. Each subject's olfactory function was assessed using the 'Sniffin' Sticks' test with a maximum score of 48. MAIN OUTCOME MEASURES: Threshold, discrimination and identification scores along with the combined olfactory score. RESULTS: The mean age of the subjects tested was 46.7 years; 46 female and 36 male. In the patient group 36 were hyposmic and 13 anosmic. In the healthy volunteers group all subjects were normosmic. In the control group the mean combined olfactory score was 34.5 (±2.5). The mean combined score in the patients group was 20.8 (±7.4). Odour threshold scores were 3.7(±2.8) for patients (hyposmics and anomics) and 8.3(±1.8) for controls. In the identification test the controls mean score was 13.6 (±1.2) for while the patients' mean score was 8.6 (±3.5). CONCLUSIONS: In our sample of the local population the combined olfactory and odour identification scores for healthy volunteers and patients with olfactory disorders are comparable with the normative data published on large samples of European populations. However, modification of a few of the distracters is recommended for British patients based on our findings.


Asunto(s)
Odorantes , Trastornos del Olfato/diagnóstico , Olfato/fisiología , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos del Olfato/fisiopatología , Estudios Prospectivos , Valores de Referencia , Reproducibilidad de los Resultados , Umbral Sensorial
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