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The selective serotonin reuptake inhibitor escitalopram (ESC) is indicated for the treatment of major depressive disorder (MDD) and of generalized anxiety disorder (GAD). Monitoring of blood levels (BLs) is strongly indicated due to ESC's high interindividual pharmacokinetic variability. The aim of this study was to analyse clinical efficacy and pharmacokinetic influences on ESC BLs, in patients with depressive disorder alone and with comorbid alcohol or benzodiazepine use disorder. Data were collected from patients treated under naturalistic conditions for whom Therapeutic Drug Monitoring (TDM) was requested to guide antidepressant drug therapy and analysed retrospectively. Particular emphasis was given to patients with alcohol or benzodiazepine use disorder. Responders according to the clinical global impression (CGI) scale were compared with nonresponders for their ESC blood level (BL). The patient sample included 344 patients from 16 psychiatric hospitals in Germany. Influencing factors that could explain 22% of ESC BLs were dose, sex and age. Variability was high between individuals, and doses up to 40 mg were common in real-world settings. Patients treated with ESC monotherapy who responded showed a trend towards higher BLs compared to nonresponders with a concentration of 15 ng/mL separating both groups. Pathological changes in liver function (indicated by elevated GGT in combination with an AST/ALT ratio ≥ 1) resulted in higher dose-corrected ESC concentrations. Influencing factors that could explain 22% of ESC blood levels were dose, sex, and age. Our findings confirm the currently recommended lower threshold level and support the need for standard TDM analyses in everyday clinical practice. The ICD 10 diagnosis alcohol dependence alone does not lead to pharmacokinetic changes in the metabolism of ESC, but altered liver function does.
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Citalopram , Trastorno Depresivo Mayor , Humanos , Escitalopram , Trastorno Depresivo Mayor/tratamiento farmacológico , Benzodiazepinas/uso terapéutico , Estudios Retrospectivos , Etanol/uso terapéuticoRESUMEN
BACKGROUND: Adipose-derived stem cells (ADSC) are multipotent cells implicated in tissue homeostasis. Obesity represents a chronic inflammatory disease associated with metabolic dysfunction and age-related mechanisms, with progressive accumulation of senescent cells and compromised ADSC function. In this study, we aimed to explore mechanisms associated with the inflammatory environment present in obesity in modulating ADSC to a senescent phenotype. We evaluated phenotypic and functional alterations through 18 days of treatment. ADSC were cultivated with a conditioned medium supplemented with a pool of plasma from eutrophic individuals (PE, n = 15) or with obesity (PO, n = 14), and compared to the control. RESULTS: Our results showed that PO-treated ADSC exhibited decreased proliferative capacity with G2/M cycle arrest and CDKN1A (p21WAF1/Cip1) up-regulation. We also observed increased senescence-associated ß-galactosidase (SA-ß-gal) activity, which was positively correlated with TRF1 protein expression. After 18 days, ADSC treated with PO showed augmented CDKN2A (p16INK4A) expression, which was accompanied by a cumulative nuclear enlargement. After 10 days, ADSC treated with PO showed an increase in NF-κB phosphorylation, while PE and PO showed an increase in p38MAPK activation. PE and PO treatment also induced an increase in senescence-associated secretory phenotype (SASP) cytokines IL-6 and IL-8. PO-treated cells exhibited decreased metabolic activity, reduced oxygen consumption related to basal respiration, increased mitochondrial depolarization and biomass, and mitochondrial network remodeling, with no superoxide overproduction. Finally, we observed an accumulation of lipid droplets in PO-treated ADSC, implying an adaptive cellular mechanism induced by the obesogenic stimuli. CONCLUSIONS: Taken together, our data suggest that the inflammatory environment observed in obesity induces a senescent phenotype associated with p38MAPK/NF-κB axis, which stimulates and amplifies the SASP and is associated with impaired mitochondrial homeostasis.
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AIMS: Quantitative estimation of cortical neurone loss in cases with chorea-acanthocytosis (ChAc) and its impact on laminar composition. METHODS: We used unbiased stereological tools to estimate the degree of cortical pathology in serial gallocyanin-stained brain sections through the complete hemispheres of three subjects with genetically verified ChAc and a range of disease durations. We compared these results with our previous data of five Huntington's disease (HD) and five control cases. Pathoarchitectonic changes were exemplarily documented in TE1 of a 61-year-old female HD-, a 60-year-old female control case, and ChAc3. RESULTS: Macroscopically, the cortical volume of our ChAc cases (ChAc1-3) remained close to normal. However, the average number of neurones was reduced by 46% in ChAc and by 33% in HD (P = 0.03 for ChAc & HD vs. controls; P = 0.64 for ChAc vs. HD). Terminal HD cases featured selective laminar neurone loss with pallor of layers III, V and VIa, a high density of small, pale, closely packed radial fibres in deep cortical layers VI and V, shrinkage, and chromophilia of subcortical white matter. In ChAc, pronounced diffuse astrogliosis blurred the laminar borders, thus masking the complete and partial loss of pyramidal cells in layer IIIc and of neurones in layers III, V and VI. CONCLUSION: ChAc is a neurodegenerative disease with distinct cortical neurodegeneration. The hypertrophy of the peripheral neuropil space of minicolumns with coarse vertical striation was characteristic of ChAc. The role of astroglia in the pathogenesis of this disorder remains to be elucidated.
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Corteza Cerebral/patología , Enfermedad de Huntington/patología , Neuroacantocitosis/patología , Adulto , Anciano , Corteza Cerebral/citología , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: The diagnosis of oral lesions is often challenging for primary healthcare providers, which explains the high number of referrals to specialist care. This favors increases in waiting lines and delays in diagnosis, contributing to high mortality rates from oral cancer. This study aimed to summarize the experience of the EstomatoNet, a telediagnosis program catering to primary care dentists and physicians from southern Brazil. STUDY DESIGN: This exploratory study included all queries received by EstomatoNet from June 2015 to December 2016. Health providers (71 dentists and 18 physicians from primary care) submitted requests including clinical information and photographs of oral lesions by means of a cloud-based platform. Specialized oral medicine teleconsultants received the data, conveyed a diagnostic hypothesis, and conveyed management recommendations. RESULTS: Actinic cheilitis (n = 41, 15.8%), squamous cell carcinoma (n = 22, 8.5%), and inflammatory hyperplasia (21, 8.1%) were the most frequent diagnoses. Teleconsultants recommended referral to specialists in 42.9% of the cases, total biopsy in 23.6%, and follow-up in 16.2%. After the EstomatoNet use, the intention to refer the patients to face-to-face consultation reduced from 96.9% to 35.1%. CONCLUSION: Telediagnosis for oral lesions is feasible and has potential to improve the quality of primary health care by bridging the gap between primary and specialized health care.
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Odontología/métodos , Enfermedades de la Boca/diagnóstico por imagen , Atención Primaria de Salud/métodos , Telemedicina , Adulto , Anciano , Actitud del Personal de Salud , Brasil , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Derivación y Consulta/estadística & datos numéricos , Adulto JovenRESUMEN
STUDY QUESTION: Does antisense oligonucleotide (ASO)-mediated down-regulation of serum fetuin-B cause infertility like fetuin-B gene deficiency in female mice? SUMMARY ANSWER: Pharmacological fetuin-B down-regulation by ASO therapy results in reversible infertility in female mice. WHAT IS KNOWN ALREADY: Female fetuin-B deficient (Fetub-/-) mice are infertile owing to premature zona pellucida (ZP) hardening. Enzyme activity studies demonstrated that fetuin-B is a potent and highly specific inhibitor of the zona proteinase ovastacin, which cleaves ZP protein 2 (ZP2) and thus mediates definitive ZP hardening. STUDY DESIGN, SIZE, DURATION: Ten fetuin-B ASO boli (100 mg/kg) were injected s.c. over 20 days in 12 female mice, and 10 phosphate-buffered saline (PBS)-treated mice were used as control. At day 20 females were mated to evaluate fetuin-B as a potential molecular target for contraception. ASO and PBS treatment was continued for ten injections. After treatment cessation at day 50, mating was continued to investigate if infertility was reversible. PARTICIPANTS/MATERIALS, SETTING, METHODS: We generated fetuin-B/ovastacin double deficient (Fetub-/-, Astl-/-) mice by conventional breeding to test if fertility of Fetub-/- female mice was restored when the target proteinase would likewise be deleted. At least five matings with each female genotype (Fetub-/- single deficient, Astl-/- single deficient, Fetub-/-, Astl-/- double deficient) were performed. To test the contraceptive effect of fetuin-B down-regulation, 22 female mice (6-13 weeks old) were treated with repetitive boli of 100 mg/kg fetuin-B ASO (n = 12) or PBS (n = 10) and mated continuously. Serum fetuin-B was determined by immunoblot before, during and after the ASO treatment. After 3 weeks of ASO treatment, in 6 females Fetub mRNA in liver was analyzed by PCR, and six PBS-treated females were used as control. Aspartate (AST) and alanine aminotransferase (ALT) were also measured in serum of six mice in each group. To determine the minimum permissive serum fetuin-B concentration required for successful fertilization IVF was performed in five fetuin-B ASO-treated mice. As a control, six females were injected with control oligonucleotides and six females were left untreated. MAIN RESULTS AND THE ROLE OF CHANCE: Fertility of Fetub-/- female mice was restored by additional ovastacin deficiency (Astl-/-). Unlike Fetub-/- mice, female Fetub-/-, Astl-/- mice were fertile, confirming ovastacin as a primary molecular target of fetuin-B. At day 20, after receiving 10 fetuin-B ASO boli, serum fetuin-B was down-regulated to 8 ± 6% (mean ± SD) of baseline level. Fetuin-B down-regulation was confirmed at the mRNA level. Fetuin-B ASO-treated females had 12.1 ± 3.1% of the liver Fetub mRNA level seen in PBS-treated females. In the following mating study, 11 out of 12 mated females failed to become pregnant during 50 days of ASO treatment and continuous mating from day 20 onwards. IVF of oocytes derived from ASO-treated females suggested that a serum fetuin-B level of less than 10 µg/ml was required to prevent pregnancy. Withdrawal of ASO treatment normalized serum fetuin-B and restored fertility; all female mice became pregnant and had litters within 60.3 ± 35.9 days after cessation of ASO treatment. The first litter was significantly smaller than that of control mice (4.6 ± 2.3 versus 6.7 ± 1.8 pups, n = 20, P = 0.04) but the smaller litter size was only temporary. The size of the second litter was similar to the first litter of control mice (7.6 ± 1.3 versus 6.7 ± 1.8 pups, n = 18, P = 0.25). LIMITATIONS, REASONS FOR CAUTION: The repeated dose of 100 mg/kg fetuin-B ASO boli caused an increased serum ALT and AST activity, suggesting hepatotoxicity. Daily vaginal plug checks indicated successful mating, but mating plugs in ASO-treated mice were less stable (vaginal tract not closed) than in control mice. WIDER IMPLICATIONS OF THE FINDINGS: Pharmacological fetuin-B down-regulation in mice caused reversible infertility. Control of ovastacin proteinase activity by fetuin-B is a necessary determinant of female fertility that can serve as a target for female contraception. Although promising in terms of human contraception, further studies analyzing the balance between sufficient fetuin-B down-regulation and tolerable side effects are required to improve safety before transfer into human reproductive biology can be considered. LARGE SCALE DATA: None. STUDY FUNDING AND COMPETING INTERESTS: The research was supported by a grant from Deutsche Forschungsgemeinschaft and by the START program of the Medical Faculty of RWTH Aachen University. The authors E.D., J.F. and W.J.-D. are named inventors on a patent application of RWTH Aachen University covering the use of fetuin-B in ovary and oocyte culture. No conflict of interest is declared by C.S. and A.C.
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Anticoncepción/métodos , Fetuína-B/antagonistas & inhibidores , Infertilidad Femenina/inducido químicamente , Anticoncepción Reversible de Larga Duración/métodos , Oligonucleótidos Antisentido/genética , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Femenino , Fertilización In Vitro , Fetuína-B/deficiencia , Fetuína-B/genética , Regulación del Desarrollo de la Expresión Génica , Dureza , Masculino , Metaloproteasas/deficiencia , Metaloproteasas/genética , Ratones , Ratones Endogámicos C57BL , Oligonucleótidos Antisentido/metabolismo , Oocitos/citología , Oocitos/crecimiento & desarrollo , Oocitos/metabolismo , Embarazo , Cultivo Primario de Células , Transducción de Señal , Espermatozoides/citología , Espermatozoides/fisiología , Zona Pelúcida/química , Glicoproteínas de la Zona Pelúcida/genética , Glicoproteínas de la Zona Pelúcida/metabolismoRESUMEN
BACKGROUND: Internationally the need for neonatal ECMO is decreasing and the Extracorporeal Life Support Organization (ELSO) recommends that centres providing neonatal ECMO should treat at least 6 children per year. METHOD: After a one-year training programme and preparation of the clinical application, neonatal ECMO was established and subsequently 41 infants [median age 1 day (1-172 days), median weight 3.25 kg (1.27-5.79 kg)] with severe respiratory failure have been treated within a 6-year period (fall 2008-fall 2014). For rescue therapy we provide inhaled nitric oxide, high-frequency oscillation and other differentiated ventilator strategies. Parallel to the clinical use of ECMO all employees have been trained in a special programme at 3-monthly intervals. RESULTS: By establishing an elaborate training programme and concentrating the treatment of critically ill newborns in one centre, the expertise of both running and preventing of neonatal ECMO due to pulmonary failure can be achieved. The diagnoses correlate to those of other centres which perform neonatal ECMO. 13 infants needed ECMO. The resulting overall survival rate was 11/12 (91.7%) infants treated with ECMO with a curative approach. All patients could be weaned from ECMO. CONCLUSION: In the context of a specialised university hospital with all treatment options for critically ill newborns and with the establishment of a specialised training programme, neonatal ECMO for pulmonary failure can achieve equally good results in comparison to those of national and international ECMO centres.
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Competencia Clínica/estadística & datos numéricos , Oxigenación por Membrana Extracorpórea/educación , Oxigenación por Membrana Extracorpórea/mortalidad , Neonatología/educación , Síndrome de Dificultad Respiratoria del Recién Nacido/mortalidad , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Curriculum , Evaluación Educacional/estadística & datos numéricos , Alemania , Prevalencia , Factores de Riesgo , Tasa de Supervivencia , Enseñanza/métodos , Resultado del TratamientoRESUMEN
Information-driven docking is currently one of the most successful approaches to obtain structural models of protein interactions as demonstrated in the latest round of CAPRI. While various experimental and computational techniques can be used to retrieve information about the binding mode, the availability of three-dimensional structures of the interacting partners remains a limiting factor. Fortunately, the wealth of structural information gathered by large-scale initiatives allows for homology-based modeling of a significant fraction of the protein universe. Defining the limits of information-driven docking based on such homology models is therefore highly relevant. Here we show, using previous CAPRI targets, that out of a variety of measures, the global sequence identity between template and target is a simple but reliable predictor of the achievable quality of the docking models. This indicates that a well-defined overall fold is critical for the interaction. Furthermore, the quality of the data at our disposal to characterize the interaction plays a determinant role in the success of the docking. Given reliable interface information we can obtain acceptable predictions even at low global sequence identity. These results, which define the boundaries between trustworthy and unreliable predictions, should guide both experts and nonexperts in defining the limits of what is achievable by docking. This is highly relevant considering that the fraction of the interactome amenable for docking is only bound to grow as the number of experimentally solved structures increases.
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Simulación del Acoplamiento Molecular , Conformación Proteica , Mapeo de Interacción de Proteínas , Proteínas/química , Biología Computacional , Bases de Datos de Proteínas , Modelos Moleculares , Unión Proteica , Programas InformáticosRESUMEN
AIMS: The prefrontal and anterior cingulate cortices are implicated in schizophrenia, and many studies have assessed volume, cortical thickness, and neuronal densities or numbers in these regions. Available data, however, are rather conflicting and no clear cortical alteration pattern has been established. Changes in oligodendrocytes and white matter have been observed in schizophrenia, introducing a hypothesis about a myelin deficit as a key event in disease development. METHODS: We investigated the dorsal anterior cingulate cortex (dACC) in 13 men with schizophrenia and 13 age- and gender-matched controls. We assessed stereologically the dACC volume, neuronal and glial densities, total neurone and glial numbers, and glia/neurone index (GNI) in both layers II-III and V-VI. RESULTS: We observed no differences in neuronal or glial densities. No changes were observed in dACC cortical volume, total neurone numbers, and total glial numbers in schizophrenia. This contrasts with previous findings and suggests that the dACC may not undergo as severe changes in schizophrenia as is generally believed. However, we observed higher glial densities in layers V-VI than in layers II-III in both controls and patients with schizophrenia, pointing to possible layer-specific effects on oligodendrocyte distribution during development. CONCLUSIONS: Using rigorous stereological methods, we demonstrate a seemingly normal cortical organization in an important neocortical area for schizophrenia, emphasizing the importance of such morphometric approaches in quantitative neuropathology. We discuss the significance of subregion- and layer-specific alterations in the development of schizophrenia, and the discrepancies between post mortem histopathological studies and in vivo brain imaging findings in patients.
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Corteza Cerebral/patología , Giro del Cíngulo/patología , Neuroglía/patología , Neuronas/patología , Esquizofrenia/patología , Adulto , Edad de Inicio , Recuento de Células , Enfermedades Desmielinizantes/patología , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Humanos , Clasificación Internacional de Enfermedades , Masculino , Persona de Mediana Edad , Oligodendroglía/patología , Psicología del Esquizofrénico , Adulto JovenRESUMEN
OBJECTIVES: To determine the diagnostic value of magnetic resonance (MR) first pass perfusion in the differentiation of benign and malignant cardiac tumours. METHODS: 24 patients with cardiac tumours (11 malignant, histopathological correlation present in all cases) were examined using MRI. In addition to morphological sequences a saturation-recovery T1w-GRE technique was implemented for tumour perfusion. The maximum relative signal enhancement (RSE[%]) and the slope of the RSE(t)-curve (slopeRSE[%/s]) of tumour tissue were assessed. A t-test was used to identify significant differences between benign and malignant tumours. Sensitivities and specificities were calculated for detection of malignant lesions and were compared with the sensitivity and specificity based on solely morphological image assessment. RESULTS: The RSE and slopeRSE of malignant cardiac tumours were significantly higher compared with benign lesions (p < 0.001 and p < 0.001). The calculated sensitivities and specificities of RSE and slopeRSE for identification of malignant lesions were 100% and 84.6% and 100% and 92.3%, respectively with cut-off values of 80% and 6%/s. The sensitivity and specificity for identification of malignant lesions on the basis of morphological imaging alone were 90.9% and 69.2%. CONCLUSIONS: With first pass perfusion, malignant cardiac masses can be identified with higher sensitivity and specificity compared with morphological image assessment alone.
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Medios de Contraste , Imagen de Difusión por Resonancia Magnética , Neoplasias Cardíacas/diagnóstico , Aumento de la Imagen , Imagen de Perfusión Miocárdica , Adolescente , Adulto , Anciano , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Neoplasias Cardíacas/patología , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión Miocárdica/métodos , Imagen de Perfusión Miocárdica/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto JovenRESUMEN
BACKGROUND: Autism spectrum disorders (ASD) are characterized by difficulties in social interaction and verbal and non verbal reciprocal communication. Face and gaze direction, which participate in non verbal communication, are described as atypical in ASD. Also body movements carry multiple social cues. Under certain circumstances, for instance when seeing two persons from far, they constitute the only support that allows the grasping of a social content. Here, we investigated the contribution of whole-body motion processing in social understanding. OBJECTIVE: The aim of the study was to evaluate whether children with ASD make use of information carried by body motion to categorize dynamic visual scenes that portrayed social interactions. METHODOLOGY: In 1973, Johansson devised a technique for studying the perception of biological motion that minimizes static form information from the stimulus, but retains motion information. In these point-light displays, the movement figure, such as a body, is represented by a small number of illuminated dots positioned to highlight the motion of the body parts. We used Johansson's model to explore the ability of children with ASD to understand social interactions based on human movement analysis. Three-second silent point-light displays were created by videotaping two actors. The two actors were either interacting together or moving side by side without interacting. A large range of social interaction displays were used to cover social scenes depicting social norms (conventional gestures and courteous attitudes), emotional situations (carrying positive or negative valences) and scenes from games (sports, dance, etc.). Children were asked to carefully watch the stimuli and to classify them according to the question "Are the two persons communicating or not?". Four sessions of 3 minutes were performed by each child. Children with ASD were compared with typically developing control children matched with either non verbal mental age or chronological age. Response and reaction time were recorded in this force-choice categorization task. RESULTS: The performance of children with ASD suggested that they were able to extract a social content from body motion. However, they were significantly less efficient than typically developing control children, either matched for non verbal mental age or chronological age. This was especially the case for the social interaction displays. Neither impaired global perceptual processing, nor cognitive development, nor emotional content could explain these lower performances. DISCUSSION AND CONCLUSION: The results are discussed in the context of an action representation deficit and a dysfunction of the mirror mechanism in ASD. In conclusion, this behavioural study highlights the potential of point-light displays as a rehabilitation tool in ASD.
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Trastornos Generalizados del Desarrollo Infantil/psicología , Relaciones Interpersonales , Percepción de Movimiento , Comunicación no Verbal , Teoría de la Mente , Niño , Comprensión , Femenino , Humanos , Masculino , Reconocimiento Visual de Modelos , Tiempo de Reacción , Valores de Referencia , Percepción SocialRESUMEN
BACKGROUND: Guideline recommendations for diffuse large-B-cell lymphoma (DLBCL) treatment are shifting from long to short treatment duration, although it is still unclear whether shortening treatment duration does not cause any harm. As interim PET (I-PET) has high negative predictive value for progression, we evaluated the cost-effectiveness of shortening treatment duration dependent on I-PET result. MATERIALS AND METHODS: We developed a Markov cohort model using the PET Re-Analysis (PETRA) database to evaluate a long treatment duration (LTD) strategy, ie 8x R-CHOP or 6x R-CHOP plus 2 R, and a short treatment duration (STD) strategy, ie 6x R-CHOP. Strategies were evaluated separately in I-PET2 positive and I-PET2 negative patients. Outcomes included total costs and quality-adjusted life-years (QALYs) per patient (pp) from a societal perspective. Net monetary benefit (NMB) per strategy was calculated using a willingness-to-pay threshold of 50,000/QALY. Robustness of model predictions was assessed in sensitivity analyses. RESULTS: In I-PET2 positive patients, shortening treatment duration led to 50.4 additional deaths per 1000 patients. The STD strategy was less effective (-0.161 [95%CI: -0.343;0.028] QALYs pp) and less costly (-2768 [95%CI: -8420;1105] pp). Shortening treatment duration was not cost-effective (incremental NMB -5281). In I-PET2 negative patients, shortening treatment duration led to 5.0 additional deaths per 1000 patients and a minor difference in effectiveness (-0.007 [95%CI: -0.136;0.140] QALY pp). The STD strategy was less costly (-5807 [95%CI: -10,724;-2685] pp) and led to an incremental NMB of 5449, indicating that it is cost-effective to shorten treatment duration. Robustness of these findings was underpinned by deterministic and probabilistic sensitivity analyses. CONCLUSION: Treatment duration should not be shortened in I-PET2 positive patients whereas it is cost-effective to shorten treatment duration in I-PET2 negative patients.
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Linfoma de Células B Grandes Difuso , Enfermedades de Transmisión Sexual , Análisis Costo-Beneficio , Duración de la Terapia , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Tomografía de Emisión de PositronesRESUMEN
Recent studies have suggested that DNA methylation is implicated in age-related changes in gene expression as well as in cognition. DNA methyltransferase 3a (Dnmt3a), which catalyzes DNA methylation, is essential for memory formation and underlying changes in neuronal and synaptic plasticity. Because caloric restriction (CR) and upregulation of antioxidants have been suggested as strategies to attenuate age-related alterations in the brain, we hypothesized that both a diet restricted in calories and transgenic overexpression of normal human Cu/Zn superoxide dismutase 1 (SOD) attenuate age-related changes in Dnmt3a in the aging mouse hippocampus. For this purpose, we performed qualitative and quantitative analyses of Dnmt3a-immunoreactivity (IR) for the hippocampal dentate gyrus (DG), CA3 and CA1-2 regions in 12- and 24-month-old mice from 4 groups, i.e. (1) wild-type (WT) mice on a control diet (WT-CD), (2) SOD-CD mice, (3) WT mice on CR (WT-CR), and (4) SOD-CR. Qualitative analyses revealed two types of Dnmt3a immunoreactive cells: type I cells--present throughout all hippocampal cell layers showing moderate levels of nuclear Dnmt3a-IR, and type II cells--a subpopulation of hippocampal cells showing very intense nuclear Dnmt3a-IR, and colocalization with Bromodeoxyuridine. Quantitative analyses indicated that the age-related increase in Dnmt3a-IR within the CA3 and CA1-2 in type I cells was attenuated by CR, but not by SOD overexpression. In contrast, the density of type II Dnmt3a immunoreactive cells showed an age-related reduction, without significant effects of both CR and SOD. These changes in Dnmt3a levels in the mouse hippocampus may have a significant impact on gene expression and associated cognitive functioning.
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Envejecimiento/fisiología , Restricción Calórica , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Hipocampo/enzimología , Superóxido Dismutasa/metabolismo , Animales , ADN Metiltransferasa 3A , Metabolismo Energético/fisiología , Femenino , Regulación de la Expresión Génica/fisiología , Hipocampo/citología , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Regulación hacia ArribaRESUMEN
BACKGROUND: Since Doppler echocardiography takes no account of pressure recovery, the true hemodynamic burden of aortic valve prostheses remains vague. The purpose of this study was to elucidate the methodological error of Doppler gradient estimation by means of a model demonstrating the different influence of aortic root diameters on net and Doppler gradients, respectively. This matters especially in small valves and the related patient/prosthesis mismatch calculation. METHODS: Two bileaflet small aortic valve prostheses (19 mm SJM Regent® and On-X® valve) were tested using a pulsatile circulatory mock loop simulator with two different aortic models: one with statistically normal diameters according to annular size, another one simulating an aortic aneurysm of 50 mm. Doppler and simultaneously recorded net gradients as well as systolic energy losses were obtained for different hemodynamic conditions. RESULTS: In all measurements a significant amount of pressure recovery was observed. In cases of aortic aneurysm systolic energy loss increased significantly for each cardiac output at each heart rate ( P < 0.0028), reflected by a significant ( P < 0.0001) increase in net gradients. The corresponding Doppler gradients were unchanged. This indicates significantly less pressure recovery ( P < 0.0001) in the aneurysmatic aorta. CONCLUSIONS: Geometry of the ascending aorta considerably alters aortic valve hemodynamic parameters. The hemodynamic function of small aortic valve prostheses, especially with corresponding normal outflow dimensions, is much better than expected from Doppler gradients. Thus, calculation of a patient/prosthesis mismatch can be misleading.
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Aorta/fisiopatología , Aneurisma de la Aorta/fisiopatología , Implantación de Prótesis de Válvulas Cardíacas/normas , Hemodinámica , Algoritmos , Aorta/diagnóstico por imagen , Aorta/cirugía , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/cirugía , Simulación por Computador , Ecocardiografía Doppler , Humanos , Diseño de PrótesisRESUMEN
Calcification is a major failure mode of bioprosthetic heart valves. So far, cost and time saving in vitro analyses of calcification potentials are unreliable, mostly due to superficial or spontaneous precipitation of the applied fluids. In this study, we developed a near-physiological non-spontaneously precipitating fluid for an accelerated in vitro calcification assessment, and validated it by analyzing the calcification potential of two prosthetic materials within two reference-tests. The first test focused on the comparison of four calcification fluids under dynamic contact with n=12 commercial bovine pericardium patches. The second one focused on the validation of the most appropriate fluid by analyzing the calcification potential of pericardium vs. polyurethane. The patches were mounted in separate test compartments and treated simultaneously with the respective fluids at an accelerated test frequency. Calcification propensity and progression were detected macroscopically and microscopically. Structural analyses of all deposits indicated hydroxyapatite by X-ray powder diffraction, which is also most commonly observed in vivo. Histological examination by von Kossa staining showed matrix internal and superficial calcifications, depending on the fluid composition. The present study reveals promising results towards the development of a meaningful, cost and time saving in vitro analysis of the calcification potential of bioprosthetic heart valves.
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Bioprótesis , Calcificación Fisiológica , Prótesis Valvulares Cardíacas , Animales , Bovinos , Precipitación Química , Válvulas Cardíacas , Ensayo de MaterialesRESUMEN
Interim 18F-fluorodeoxyglucose positron emission tomography (Interim-18F-FDG-PET, hereafter I-PET) has the potential to guide treatment of patients with diffuse large B-cell lymphoma (DLBCL) if the prognostic value is known. The aim of this study was to determine the optimal timing and response criteria for evaluating prognosis with I-PET in DLBCL. Individual patient data from 1692 patients with de novo DLBCL were combined and scans were harmonized. I-PET was performed at various time points during treatment with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) therapy. Scans were interpreted using the Deauville score (DS) and change in maximum standardized uptake value (ΔSUVmax). Multilevel Cox proportional hazards models corrected for International Prognostic Index (IPI) score were used to study the effects of timing and response criteria on 2-year progression-free survival (PFS). I-PET after 2 cycles (I-PET2) and I-PET4 significantly discriminated good responders from poor responders, with the highest hazard ratios (HRs) for I-PET4. Multivariable HRs for a PET-positive result at I-PET2 and I-PET4 were 1.71 and 2.95 using DS4-5, 4.91 and 6.20 using DS5, and 2.93 and 4.65 using ΔSUVmax, respectively. ΔSUVmax identified a larger proportion of poor responders than DS5 did. For all criteria, the negative predictive value was >80%, and positive predictive values ranged from 30% to 70% at I-PET2 and I-PET4. Unlike I-PET1, I-PET3 discriminated good responders from poor responders using DS4-5 and DS5 thresholds (HRs, 2.94 and 4.67, respectively). I-PET2 and I-PET4 predict good response equally during R-CHOP therapy in DLBCL. Optimal timing and response criteria depend on the clinical context. Good response at I-PET2 is suggested for de-escalation trials, and poor response using ΔSUVmax at I-PET4 is suggested for randomized trials that are evaluating new therapies.
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Linfoma de Células B Grandes Difuso , Fluorodesoxiglucosa F18 , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Tomografía de Emisión de Positrones , Pronóstico , Vincristina/uso terapéuticoRESUMEN
Calcification is a major reason for the failure of bioprosthetic heart valves. Therefore, several attempts towards an accelerated in vitro model were undertaken in order to provide a cost- and time-saving method for the analysis of calcification processes. Due to the problem of superficial or spontaneous precipitation, which occurred in the fluids applied, we focused our study on the development of a near-physiological calcification fluid. The desired fluid should not precipitate spontaneously and should neither promote nor inhibit calcification. Eleven different fluid compositions were tested without contact to potentially calcifying materials. Crucial factors regarding the fluid properties were the ionic product, the ionic strength, and the degree of supersaturation concerning dicalciumphosphate-dihydrate, octacalciumphosphate, and hydroxyapatite. The fluids were kept in polyethylene bottles and exposed to a slight vibration within a durability tester at 37 °C. The precipitation propensity was monitored optically and colorimetrically. A structural analysis of the deposits was carried out by x-ray powder diffraction and IR-spectroscopy, which showed the development of the crystal phases that are relevant in vivo. Only two of the fluids did not precipitate. Resulting from the computations of the effective fluid contents, the saturation degree concerning dicalciumphosphate-dihydrate seems to be the key factor for spontaneous precipitation.
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Bioprótesis , Calcificación Fisiológica , Válvulas Cardíacas , Animales , Cloruro de Calcio , Bovinos , Precipitación Química , Ensayo de Materiales , Pericardio , Fosfatos , Cloruro de PotasioRESUMEN
The morphometric parameters of the villous tree are a strong indicator of deviant placentas. Methods have been established to digitally reconstruct small peripheral branches by tracing with 3D Microscopy at subcellular resolution. Micro-CT can help scale up the scanning of villous trees with resolution in the range of a few micrometers. As placental tissue samples are routinely conserved and archived by fixation and paraffin embedding, the villous structures are inaccessible to Micro-CT imaging due to poor contrast between paraffin and paraffinized tissue. We present a novel procedure for contrast enhancement by selectively replacing wax by air in the intervillous space.
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Adhesión en Parafina , Placenta/diagnóstico por imagen , Microtomografía por Rayos X , Femenino , Humanos , EmbarazoRESUMEN
Multiple-junction structures were formed, on a microscopic scale, at room temperature, by the application of a strong electric field across originally homogeneous crystals of the ternary chalcopyrite semiconductor CulnSe(2). After removal of the electric field, the structures were examined with electron beam-induced current microscopy and their current-voltage characteristics were measured. Bipolar transistor action was observed, indicating that sharp bulk junctions can form in this way at low ambient temperatures. The devices are stable under normal (low-voltage) operating conditions. Possible causes for this effect, including electromigration and electric field-assisted defect reactions, are suggested.