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Doublecortin (Dcx) defines a growing family of microtubule (MT)-associated proteins (MAPs) involved in neuronal migration and process outgrowth. We show that Dcx is essential for the function of Kif1a, a kinesin-3 motor protein that traffics synaptic vesicles. Neurons lacking Dcx and/or its structurally conserved paralogue, doublecortin-like kinase 1 (Dclk1), show impaired Kif1a-mediated transport of Vamp2, a cargo of Kif1a, with decreased run length. Human disease-associated mutations in Dcx's linker sequence (e.g., W146C, K174E) alter Kif1a/Vamp2 transport by disrupting Dcx/Kif1a interactions without affecting Dcx MT binding. Dcx specifically enhances binding of the ADP-bound Kif1a motor domain to MTs. Cryo-electron microscopy and subnanometer-resolution image reconstruction reveal the kinesin-dependent conformational variability of MT-bound Dcx and suggest a model for MAP-motor crosstalk on MTs. Alteration of kinesin run length by MAPs represents a previously undiscovered mode of control of kinesin transport and provides a mechanism for regulation of MT-based transport by local signals.
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Cinesinas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Neuronas/metabolismo , Neuropéptidos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Proteínas de Dominio Doblecortina , Proteína Doblecortina , Quinasas Similares a Doblecortina , Femenino , Masculino , Ratones , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/deficiencia , Microtúbulos/metabolismo , Neuronas/citología , Neuropéptidos/deficiencia , Proteínas Serina-Treonina Quinasas/deficienciaRESUMEN
Arteriogenesis is a process by which a pre-existing arterioarterial anastomosis develops into a functional collateral network following an arterial occlusion. Alternatively activated macrophages polarized by IL10 have been described to promote collateral growth. This study investigates the effect of different levels of IL10 on hind-limb reperfusion and the distribution of perivascular macrophage activation types in mice after femoral artery ligation (FAL). IL10 and anti-IL10 were administered before FAL and the arteriogenic response was measured by Laser-Doppler-Imaging perioperatively, after 3, 7, and 14 d. Reperfusion recovery was accelerated when treated with IL10 and impaired with anti-IL10. Furthermore, symptoms of ischemia on ligated hind-limbs had the highest incidence after application of anti-IL10. Perivascular macrophages were immunohistologically phenotyped using CD163 and CD68 in adductor muscle segments. The proportion of alternatively activated macrophages (CD163+/CD68+) in relation to classically activated macrophages (CD163-/CD68+) observed was the highest when treated with IL10 and suppressed with anti-IL10. This study underlines the proarteriogenic response with increased levels of IL10 and demonstrates an in-vivo alteration of macrophage activation types in the perivascular bed of growing collaterals.
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Arteria Femoral/lesiones , Miembro Posterior/irrigación sanguínea , Interleucina-10/farmacología , Isquemia/diagnóstico por imagen , Macrófagos/inmunología , Animales , Anticuerpos/farmacología , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Polaridad Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Miembro Posterior/inmunología , Interleucina-10/sangre , Isquemia/inmunología , Activación de Macrófagos/efectos de los fármacos , Macrófagos/efectos de los fármacos , Ratones , Receptores de Superficie Celular/metabolismo , ReperfusiónRESUMEN
Whereas many genes associated with intellectual disability (ID) encode synaptic proteins, transcriptional defects leading to ID are less well understood. We studied a large, consanguineous pedigree of Arab origin with seven members affected with ID and mild dysmorphic features. Homozygosity mapping and linkage analysis identified a candidate region on chromosome 17 with a maximum multipoint logarithm of odds score of 6.01. Targeted high-throughput sequencing of the exons in the candidate region identified a homozygous 4-bp deletion (c.169_172delCACT) in the METTL23 (methyltransferase like 23) gene, which is predicted to result in a frameshift and premature truncation (p.His57Valfs*11). Overexpressed METTL23 protein localized to both nucleus and cytoplasm, and physically interacted with GABPA (GA-binding protein transcription factor, alpha subunit). GABP, of which GABPA is a component, is known to regulate the expression of genes such as THPO (thrombopoietin) and ATP5B (ATP synthase, H+ transporting, mitochondrial F1 complex, beta polypeptide) and is implicated in a wide variety of important cellular functions. Overexpression of METTL23 resulted in increased transcriptional activity at the THPO promoter, whereas knockdown of METTL23 with siRNA resulted in decreased expression of ATP5B, thus revealing the importance of METTL23 as a regulator of GABPA function. The METTL23 mutation highlights a new transcriptional pathway underlying human intellectual function.
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Metilasas de Modificación del ADN/metabolismo , Factor de Transcripción de la Proteína de Unión a GA/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Metilasas de Modificación del ADN/genética , Femenino , Factor de Transcripción de la Proteína de Unión a GA/genética , Genotipo , Humanos , Inmunoprecipitación , Masculino , ATPasas de Translocación de Protón Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Polimorfismo de Nucleótido Simple/genética , Unión Proteica , ARN Interferente Pequeño , Trombopoyetina/genética , Trombopoyetina/metabolismo , Técnicas del Sistema de Dos HíbridosRESUMEN
BACKGROUND: Altered brain connectivity is implicated in the development and clinical burden of schizophrenia. Relative to matched controls, schizophrenia patients show (1) a global and regional reduction in the integrity of the brain's white matter (WM), assessed using diffusion tensor imaging (DTI) fractional anisotropy (FA), and (2) accelerated age-related decline in FA values. In the largest mega-analysis to date, we tested if differences in the trajectories of WM tract development influenced patient-control differences in FA. We also assessed if specific tracts showed exacerbated decline with aging. METHODS: Three cohorts of schizophrenia patients (total n = 177) and controls (total n = 249; age = 18-61 years) were ascertained with three 3T Siemens MRI scanners. Whole-brain and regional FA values were extracted using ENIGMA-DTI protocols. Statistics were evaluated using mega- and meta-analyses to detect effects of diagnosis and age-by-diagnosis interactions. RESULTS: In mega-analysis of whole-brain averaged FA, schizophrenia patients had lower FA (P = 10-11 ) and faster age-related decline in FA (P = 0.02) compared with controls. Tract-specific heterochronicity measures, that is, abnormal rates of adolescent maturation and aging explained approximately 50% of the regional variance effects of diagnosis and age-by-diagnosis interaction in patients. Interactive, three-dimensional visualization of the results is available at www.enigma-viewer.org. CONCLUSION: WM tracts that mature later in life appeared more sensitive to the pathophysiology of schizophrenia and were more susceptible to faster age-related decline in FA values. Hum Brain Mapp 37:4673-4688, 2016. © 2016 Wiley Periodicals, Inc.
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Envejecimiento/patología , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Esquizofrenia/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/crecimiento & desarrollo , Adolescente , Adulto , Estudios de Cohortes , Imagen de Difusión Tensora , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Members of the highly conserved homeobox (HOX) gene family encode transcription factors that confer cellular and tissue identities along the antero-posterior axis of mice and humans. We have identified a founder homozygous missense mutation in HOXB1 in two families from a conservative German American population. The resulting phenotype includes bilateral facial palsy, hearing loss, and strabismus and correlates extensively with the previously reported Hoxb1(-/-) mouse phenotype. The missense variant is predicted to result in the substitution of a cysteine for an arginine at amino acid residue 207 (Arg207Cys), which corresponds to the highly conserved Arg5 of the homeodomain. Arg5 interacts with thymine in the minor groove of DNA through hydrogen bonding and electrostatic attraction. Molecular modeling and an in vitro DNA-protein binding assay predict that the mutation would disrupt these interactions, destabilize the HOXB1:PBX1:DNA complex, and alter HOXB1 transcriptional activity.
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Parálisis Facial/genética , Pérdida Auditiva Sensorineural/genética , Proteínas de Homeodominio/genética , Mutación Missense , Estrabismo/genética , Animales , Secuencia de Bases , Niño , Preescolar , Femenino , Efecto Fundador , Humanos , Masculino , Ratones , Síndrome de Mobius/genética , Modelos Moleculares , Linaje , Fenotipo , Transcripción Genética , Activación TranscripcionalRESUMEN
OBJECTIVE: Interindividual variation in pathways affecting cellular cholesterol metabolism can influence levels of plasma cholesterol, a well-established risk factor for cardiovascular disease. Inherent variation among immortalized lymphoblastoid cell lines from different donors can be leveraged to discover novel genes that modulate cellular cholesterol metabolism. The objective of this study was to identify novel genes that regulate cholesterol metabolism by testing for evidence of correlated gene expression with cellular levels of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) mRNA, a marker for cellular cholesterol homeostasis, in a large panel of lymphoblastoid cell lines. APPROACH AND RESULTS: Expression array profiling was performed on 480 lymphoblastoid cell lines established from participants of the Cholesterol and Pharmacogenetics (CAP) statin clinical trial, and transcripts were tested for evidence of correlated expression with HMGCR as a marker of intracellular cholesterol homeostasis. Of these, transmembrane protein 55b (TMEM55B) showed the strongest correlation (r=0.29; P=4.0E-08) of all genes not previously implicated in cholesterol metabolism and was found to be sterol regulated. TMEM55B knockdown in human hepatoma cell lines promoted the decay rate of the low-density lipoprotein receptor, reduced cell surface low-density lipoprotein receptor protein, impaired low-density lipoprotein uptake, and reduced intracellular cholesterol. CONCLUSIONS: Here, we report identification of TMEM55B as a novel regulator of cellular cholesterol metabolism through the combination of gene expression profiling and functional studies. The findings highlight the value of an integrated genomic approach for identifying genes that influence cholesterol homeostasis.
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Colesterol/metabolismo , Linfocitos/metabolismo , Receptores de LDL/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Perfilación de la Expresión Génica , Células Hep G2 , Hepatocitos/metabolismo , Homeostasis , Humanos , Hidroximetilglutaril-CoA Reductasas/biosíntesis , Hidroximetilglutaril-CoA Reductasas/genética , Líquido Intracelular/metabolismo , Metabolismo de los Lípidos/genética , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismoRESUMEN
Although autism has a clear genetic component, the high genetic heterogeneity of the disorder has been a challenge for the identification of causative genes. We used homozygosity analysis to identify probands from nonconsanguineous families that showed evidence of distant shared ancestry, suggesting potentially recessive mutations. Whole-exome sequencing of 16 probands revealed validated homozygous, potentially pathogenic recessive mutations that segregated perfectly with disease in 4/16 families. The candidate genes (UBE3B, CLTCL1, NCKAP5L, ZNF18) encode proteins involved in proteolysis, GTPase-mediated signaling, cytoskeletal organization, and other pathways. Furthermore, neuronal depolarization regulated the transcription of these genes, suggesting potential activity-dependent roles in neurons. We present a multidimensional strategy for filtering whole-exome sequence data to find candidate recessive mutations in autism, which may have broader applicability to other complex, heterogeneous disorders.
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Trastorno Autístico/genética , Exones , Genes Recesivos , Mutación , Neuronas , Proteínas Adaptadoras Transductoras de Señales/genética , Cadenas Pesadas de Clatrina/genética , Exones/genética , Genoma Humano , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Homocigoto , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Neuronas/metabolismo , Neuronas/fisiología , Proteínas Oncogénicas/genética , Transcripción Genética , Ubiquitina-Proteína Ligasas/genéticaRESUMEN
Exchange coupled ferri-/ferromagnetic heterostructures are a possible material composition for future magnetic storage and sensor applications. In order to understand the driving mechanisms in the demagnetization process, we perform micromagnetic simulations by employing the Landau-Lifshitz-Gilbert equation. The magnetization reversal is dominated by pinning events within the amorphous ferrimagnetic layer and at the interface between the ferrimagnetic and the ferromagnetic layer. The shape of the computed magnetization reversal loop corresponds well with experimental data, if a spatial variation of the exchange coupling across the ferri-/ferromagnetic interface is assumed.
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We demonstrate all-optical magnetic switching (AOS) in an amorphous Tb30Fe70 thin film, triggered by a 5.1 MHz laser oscillator. The magnetic layer is grown on SiO2/Si substrate. An identical magnetic film deposited on a microscope glass slide reveals no AOS but solely thermally induced demagnetization. This effect is due to heat accumulation by multiple laser pulses because of the low thermal conductivity of the glass substrate. In contrast, the use of a proper heat sink (e.g. SiO2/Si) avoids the need for low repetitive laser amplifier systems to induce AOS and paves the way for a cheap and simple technical implementation using conventional laser oscillators.
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Studies have shown clearly that childhood mistreatment, abuse and neglect are associated with severe inflammatory disease in adulthood (e. g. cancer, heart disease, autoimmune disorder) and shortened life span. This review deals with the psychoneuroimmunological pathways of this connection. It shows that chronic stressors interfere very early in life with those protective mechanisms of the biological stress system that normally down-regulate potentially harmful inflammation. In the long term, serious inflammatory diseases, such as allergic asthma, can result. In this review, the pathogenetic connections between allergic asthma and early stress and stress system dysfunction are discussed. As our understanding of the dysfunctional psychophysiological mechanisms of inflammatory disease increases, psychodiagnostic and psychotherapeutic intervention in the treatment of physical disease will become more specific.
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Maltrato a los Niños/estadística & datos numéricos , Enfermedades del Sistema Inmune/etiología , Inflamación/etiología , Psiconeuroinmunología , Estrés Psicológico/complicaciones , Adolescente , Adulto , Niño , Humanos , Enfermedades del Sistema Inmune/epidemiología , Enfermedades del Sistema Inmune/inmunología , Inflamación/epidemiología , Inflamación/inmunología , Estrés Psicológico/epidemiología , Estrés Psicológico/inmunologíaRESUMEN
Deployment of ultracold atom interferometers (AI) into space will capitalize on quantum advantages and the extended freefall of persistent microgravity to provide high-precision measurement capabilities for gravitational, Earth, and planetary sciences, and to enable searches for subtle forces signifying physics beyond General Relativity and the Standard Model. NASA's Cold Atom Lab (CAL) operates onboard the International Space Station as a multi-user facility for fundamental studies of ultracold atoms and to mature space-based quantum technologies. We report on pathfinding experiments utilizing ultracold 87Rb atoms in the CAL AI. A three-pulse Mach-Zehnder interferometer was studied to understand the influence of ISS vibrations. Additionally, Ramsey shear-wave interferometry was used to manifest interference patterns in a single run that were observable for over 150 ms free-expansion time. Finally, the CAL AI was used to remotely measure the Bragg laser photon recoil as a demonstration of the first quantum sensor using matter-wave interferometry in space.
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BACKGROUND: Quantitative evaluation of mosaics of photoreceptors and neurons is essential in studies on development, aging and degeneration of the retina. Manual counting of samples is a time consuming procedure while attempts to automatization are subject to various restrictions from biological and preparation variability leading to both over- and underestimation of cell numbers. Here we present an adaptive algorithm to overcome many of these problems.Digital micrographs were obtained from cone photoreceptor mosaics visualized by anti-opsin immuno-cytochemistry in retinal wholemounts from a variety of mammalian species including primates. Segmentation of photoreceptors (from background, debris, blood vessels, other cell types) was performed by a procedure based on Rudin-Osher-Fatemi total variation (TV) denoising. Once 3 parameters are manually adjusted based on a sample, similarly structured images can be batch processed. The module is implemented in MATLAB and fully documented online. RESULTS: The object recognition procedure was tested on samples with a typical range of signal and background variations. We obtained results with error ratios of less than 10% in 16 of 18 samples and a mean error of less than 6% compared to manual counts. CONCLUSIONS: The presented method provides a traceable module for automated acquisition of retinal cell density data. Remaining errors, including addition of background items, splitting or merging of objects might be further reduced by introduction of additional parameters. The module may be integrated into extended environments with features such as 3D-acquisition and recognition.
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Algoritmos , Inteligencia Artificial , Interpretación de Imagen Asistida por Computador/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Células Fotorreceptoras de Vertebrados/citología , Retinoscopía/métodos , Animales , MamíferosRESUMEN
The relationship between emotional states and immune system activity is characterized by bidirectional influences; however, limited information is available regarding the temporal dynamics of these effects. The goal of this investigation was to examine how these psychoimmunological interdependencies unfold over time under conditions of "life as it is lived". For this purpose, three healthy women collected their entire urine over a period of approximately two months at 12-h intervals (8 am-8 pm, 8 pm-8 am), resulting in a total of 112 to 126 consecutive measurements per subject. In addition, among other regular psychological assessments, the subjects completed the EWL-60-S, an emotional state questionnaire, each morning and evening. To assess the extent of T-helper type 1 immune activation, the neopterin per creatinine concentration was measured in the urine samples using high-pressure liquid chromatography. The dynamic relationships between the time series of the six emotional states (performance-related activity, general inactivity, extraversion/introversion, general feeling of comfort, emotional irritation, anxiety/depressiveness) and urinary neopterin levels were estimated in vector-autoregressive models and evaluated using Granger-causality tests, impulse-response functions and forecast error variance decompositions. The findings showed that emotional states explained up to 20% of the variance of urinary neopterin per creatinine levels, whereby most of the effects occurred within a period of approximately three days. Across all subjects, increases in anxiety/depressiveness and extraversion led to increases in neopterin levels, while a general feeling of comfort led to decreases in neopterin. These results emphasize the importance of the interdependencies between emotional states and immune system activity and showcase the potential that intensive longitudinal study designs offer for psychoneuroimmunology.
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Sistema Inmunológico , Humanos , Femenino , Neopterin/orina , Factores de Tiempo , Creatinina/orina , Estudios LongitudinalesRESUMEN
Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects cartilage and bone. Psychological stress can both trigger disease exacerbation and result from disease activity. As standard pharmacological interventions alone have limited success in treating RA, a more comprehensive biopsychosocial approach to treatment has been recommended. In this prospective randomized controlled trial (RCT), a psychotherapeutically guided, group-based intervention program will be conducted with RA patients over a period of 9 months. This program combines a dynamic-interactional model with disorder-specific coping-oriented perspectives to improve patients' social, emotional, and problem-solving competencies as well as stress system functional status. The enrolment of 440 patients, randomly allocated to either an intervention (n = 220) or control group (n = 220), is planned. To evaluate the intervention effect, various indicators of RA disease activity, stress system activity, and psychological condition will be assessed through sets of standardized questionnaires and biochemical analyses of blood and saliva samples. Moreover, healthcare-related costs for each patient will be obtained using routine health insurance data. Outcome variables will be measured in all patients at regular intervals prior to intervention (baseline), during the 9-month intervention (five time points), and during a 9-month follow-up phase (three time points), allowing the comprehensive analysis of within- and between-subject effects, i.e. trajectories of the target variables in the intervention and control groups. In addition, to investigate the intervention effects on real-life stress system functioning in RA, 10 integrative single-case studies (n = 5 from the intervention group, n = 5 from the control group) will be conducted. In each study, once before and after the 9-month intervention, urine samples will be collected, and patients will fill out questionnaires for approximately 1 month at 12-h intervals. Moreover, weekly in-depth interviews will be conducted with patients to determine their previous week's emotionally positive and negative incidents. Using time series analysis, it is then possible to investigate whether and how stress system function in these RA patients has improved from the applied intervention. By using both an investigational macro- and microperspective, this project aims to evaluate a psychological intervention in the routine care of individuals with RA.Trial registration German Clinical Trials Register DRKS00028144. Registered on 1 March 2022.
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Artritis Reumatoide , Intervención Psicosocial , Humanos , Resultado del Tratamiento , Artritis Reumatoide/terapia , Artritis Reumatoide/tratamiento farmacológico , Proyectos de Investigación , Encuestas y Cuestionarios , Enfermedad Crónica , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Psychoneuroimmunology (PNI) is an area of interdisciplinary research exploring the complex interactions within the immuno-neuro-endocrine system in response to psychosocial influences. Such influences can trigger neurological changes, leading to immunological effects related to the emergence and course of various diseases. This concise clinical review explores the role of PNI in oral medicine in three exemplary models of oral disease: periodontitis, herpes labialis, and oral lichen planus. Previous literature has shown that psychosocial stress is related to exacerbations in these three oral diseases and to poorer overall oral health. The presumed biological mechanisms affect the activity of stress axes, i.e. the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS), and subsequent immune system dysregulation. Although these PNI mechanisms remain poorly understood, several stress reduction interventions in clinical oral medicine have already yielded promising results. In future work, the elucidation of pathways within PNI networks will require carefully designed studies with sensitive methodology, e.g. the integrative single-case design. A biopsychosocial approach has the potential to move disease models in oral medicine from simple connections rooted in empirical dualism and reductionism to the establishment of network-based models. Further research on these complex connections should lead to novel clinical approaches and preventive strategies in oral medicine.
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Medicina Oral , Psiconeuroinmunología , Estrés Psicológico , HumanosRESUMEN
Understanding the factors which lead to the (in)stability of the chemistry and sensory of hoppy beer styles such as India Pale Ales (IPAs) has become a major concern for many brewers. Therefore, the evolution of several volatiles under different storage conditions (room temperature, cold storage, forced aging) was investigated in eleven hoppy ales and one lager which were commercially produced in Germany. Compared to the lager, the fresh ales contained higher initial aldehyde levels. Furthermore, the distribution of lipid oxidation and Maillard reaction products differed from those typically found in lager beer. Upon storage, significant increases of some staling aldehydes were observed. Interestingly, the concentrations of some hop aroma volatiles like terpenoids (i.e. linalool and geraniol) were relatively stable throughout storage and counteracted "oxidized" impressions in ales high in these compounds. In comparison, hop aroma in some ales was driven by less stable volatiles such as esters.
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Cerveza , Odorantes , Aldehídos , Cerveza/análisis , Alemania , Odorantes/análisis , TerpenosRESUMEN
In a previous integrative single-case study, we collected biological, psychological and social time-series data on a 25-year-old healthy woman over the course of 126 12-h intervals (63 days) and used urinary neopterin as an indicator of cellular immune activity [Schubert et al. 2012 (1)]. The present re-evaluation introduced Dynamic Complexity (DC) as an additional non-linear and non-stationary measure to further investigate the subject's biopsychosocial dynamics during the study. The new time series dealing with urinary neopterin complexity revealed a cyclic, circaseptan (about-weekly) repeating pattern (6.59 days). The only weekly reoccurring events over the course of the study that were associated with this immunological pattern were the in-depth interviews with the subject (mean distance between interviews: 6.5 days). Superposed epoch analysis (SEA) revealed a U-shaped relation between neopterin complexity and interviews, with a decrease in neopterin complexity before and during interviews and an increase after interviews. Furthermore, the complexity scores for irritation, anxiousness/depressiveness and mental activity were positively correlated with neopterin complexity. The results suggest that the interviews, which had been found to be related to the subject's need for educational and/or social accomplishment, were marked by stress (decrease in psycho-immunological flexibility and adaptability), which was then relieved after the interviews (increase in psycho-immunological flexibility and adaptability). It appears that the subject's cellular immune activity, as indicated by neopterin complexity, functionally mirrored the emotional meaning she ascribed to the in-depth interviews. This re-evaluation is in line with the view that biopsychosocial research requires multimodal analysis of single cases based on qualitative (e.g., in-depth interviews) and quantitative (e.g., time series analysis) data under conditions of "life as it is lived".
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Recently studies based on limited sample sizes procured from minor hop growing regions have speculated that the elemental profile of hops can possibly be used to authenticate the origin of a hop because changes in hop elemental profiles were realted to growing region and that these changes might also be related to beer quality. To explore this further, 205 hop samples (i.e. 203 whole cone hops and 2 pelletized samples) compromised of 19 varieties were procured from the major hop growing regions (i.e. the U.S. and Germany). These hops were digested with microwave digestion and analyzed for 25 elements using ICP-MS. Hops from most of the U.S. regions (mainly WA) had vastly different elemental profiles than hops from Germany. German hops had significantly lower concentrations for most of the elements except for Cu and K. Interestingly, high alpha varieties had significantly different elemental profiles than varieties bred for aroma purposes. Dry-hopping trials were then performed in an ale and a lager with the hops that had significantly different elemental profiles. Although heavy metals were extracted from hops into beer, at the 5 g/L dry-hopping load used in this study, beer concentrations of these elements remained below regulated water quality standards set by Germany, the U.S., and Canada. Based on electron paramagnetic resonance, dry-hopping had an antioxidant impact on beer regardless of the original elemental profile of the hops which was correlated to hop polyphenol and α/ ß - acid concentrations. Overall these results highlight that many factors including location have the potential to influence the elemental profile of hops and that changes in the elemental profiles of hops can be related to beer quality.