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1.
Epidemiol Psychiatr Sci ; 33: e19, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563188

RESUMO

AIMS: Depressive disorders are ranked as the single leading cause of disability worldwide. Despite immense efforts, there is no evidence of a global reduction in the disease burden in recent decades. The aim of the study was to determine the public health impact of the current service system (status quo), to quantify its effects on the depression-related disease burden and to identify the most promising strategies for improving healthcare for depression on the population level. METHODS: A Markov model was developed to quantify the impact of current services for depression (including prevention, treatment and aftercare interventions) on the total disease burden and to investigate the potential of alternative scenarios (e.g., improved reach or improved treatment effectiveness). Parameter settings were derived from epidemiological information and treatment data from the literature. Based on the model parameters, 10,000,000 individual lives were simulated for each of the models, based on monthly transition rates between dichotomous health states (healthy vs. diseased). Outcome (depression-related disease burden) was operationalized as the proportion of months spent in depression. RESULTS: The current healthcare system alleviates about 9.5% (95% confidence interval [CI]: 9.2%-9.7%) of the total disease burden related to depression. Chronic cases cause the majority (83.2%) of depression-related burden. From a public health perspective, improving the reach of services holds the largest potential: Maximum dissemination of prevention (26.9%; CI: 26.7%-27.1%) and treatment (26.5%; CI: 26.3%-26.7%) would result in significant improvements on the population level. CONCLUSIONS: The results confirm an urgent need for action in healthcare for depression. Extending the reach of services is not only more promising but also probably more achievable than increasing their effectiveness. Currently, the system fails to address the prevention and treatment of chronic cases. The large proportion of the disease burden associated with chronic courses highlights the need for improved treatment policies and clinical strategies for this group (e.g., disease management and adaptive or personalized interventions). The model complements the existing literature by providing a new perspective on the depression-related disease burden and the complex interactions between healthcare services and the lifetime course.


Assuntos
Depressão , Serviços de Saúde Mental , Humanos , Depressão/epidemiologia , Depressão/terapia
2.
Eur Urol Oncol ; 7(5): 973-977, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38480032

RESUMO

Sarcomatoid renal cell carcinoma (sRCC) is histologically heterogeneous, with variable sarcomatoid amounts intermixed within epithelial carcinoma. However, the current classification for this aggressive disease is homogeneous and agnostic to the sarcomatoid proportion. We investigated whether sRCC subclassification has prognostic value and can reveal the biology underlying dedifferentiation and its clinical aggressiveness. On the basis of the intratumoral abundance of sarcomatoid features, cases were classified as sarcomatoid-high (≥10% sarcomatoid features) or sarcomatoid-low (<10% sarcomatoid features) in a cohort of 104 consecutive patients with sRCC undergoing nephrectomy at a single center. In comparison to sarcomatoid-low patients (n = 52), sarcomatoid-high patients (n = 52) had significantly shorter overall survival (median 14.5 vs 62.9 mo; p < 0.001), which was confirmed on multivariable analysis, and significantly shorter median metastasis-free survival among patients with clinically localized disease (10.7 vs 39.0 mo; p = 0.043). Transcriptomic analyses of 45 sRCC tumors revealed significant upregulation of nine hallmark pathways related to cell cycle/proliferation, epithelial-to-mesenchymal transition, reactive oxidative species, and interferon-α signaling among sarcomatoid-high (n = 24) versus sarcomatoid-low (n = 21) tumors. Categorization into transcriptomic clusters revealed predominance of proliferative, inflammatory, and immune effector phenotypes among sarcomatoid-high tumors, versus a hypoxia/angiogenesis phenotype among sarcomatoid-low tumors. Overall, these findings indicate prognostic value for sRCC subclassification into high versus low sarcomatoid groups and highlight key biology underlying the differences in clinical outcomes. PATIENT SUMMARY: Sarcomatoid renal cell carcinoma (sRCC) is a highly aggressive form of kidney cancer. The percentage of sarcomatoid features varies among tumors, but sRCC is still defined as a single kidney cancer type. Our results show that grouping patients according to their percentage of sarcomatoid features improves prediction of whether their tumors will become metastatic or lethal, and reveal molecular differences that may be important for this disease. Future assignment of sRCC to high and low sarcomatoid groups may help in guiding research and patient management.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/patologia , Neoplasias Renais/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Prognóstico , Adulto , Idoso de 80 Anos ou mais , Transição Epitelial-Mesenquimal
3.
Astrobiology ; 23(12): 1245-1258, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38054949

RESUMO

With advances in commercial space launch capabilities and reduced costs to orbit, humans may arrive on Mars within a decade. Both to preserve any signs of past (and extant) martian life and to protect the health of human crews (and Earth's biosphere), it will be necessary to assess the risk of cross-contamination on the surface, in blown dust, and into the near-subsurface (where exploration and resource-harvesting can be reasonably anticipated). Thus, evaluating for the presence of life and biosignatures may become a critical-path Mars exploration precursor in the not-so-far future, circa 2030. This Special Collection of papers from the Atacama Rover Astrobiology Drilling Studies (ARADS) project describes many of the scientific, technological, and operational issues associated with searching for and identifying biosignatures in an extreme hyperarid region in Chile's Atacama Desert, a well-studied terrestrial Mars analog environment. This paper provides an overview of the ARADS project and discusses in context the five other papers in the ARADS Special Collection, as well as prior ARADS project results.


Assuntos
Exobiologia , Marte , Humanos , Exobiologia/métodos , Meio Ambiente Extraterreno , Poeira
4.
STAR Protoc ; 4(3): 102493, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37572324

RESUMO

We present a protocol to conduct functional magnetic resonance spectroscopy (fMRS) in human participants before, during, and after training on a visual task. We describe steps for participant setup, volume-of-interest placement, fMRS measurement, and post-scan tests. We discuss the design, analysis, and interpretation of fMRS experiments. This protocol can be adapted to investigate the dynamics of chief excitatory and inhibitory neurotransmitters (glutamate and γ-aminobutyric acid, GABA, respectively) while participants perform or learn perceptual, motor, or cognitive tasks. For complete details on the use and execution of this protocol, please refer to Frank et al. (2022).1.


Assuntos
Ácido Glutâmico , Aprendizagem , Humanos , Espectroscopia de Ressonância Magnética/métodos , Ácido gama-Aminobutírico
5.
Sci Rep ; 13(1): 12362, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-37524748

RESUMO

The perception of coherent form configurations in natural scenes relies on the activity of early visual areas that respond to local orientation cues. Subsequently, high-level visual areas pool these local signals to construct a global representation of the initial visual input. However, it is still debated whether neurons in the early visual cortex respond also to global form features. Glass patterns (GPs) are visual stimuli employed to investigate local and global form processing and consist of randomly distributed dots pairs called dipoles arranged to form specific global configurations. In the current study, we used GPs and functional magnetic resonance imaging (fMRI) adaptation to reveal the visual areas that subserve the processing of oriented GPs. Specifically, we adapted participants to vertically oriented GP, then we presented test GPs having either the same or different orientations with respect to the adapting GP. We hypothesized that if local form features are processed exclusively by early visual areas and global form by higher-order visual areas, then the effect of visual adaptation should be more pronounced in higher tier visual areas as it requires global processing of the pattern. Contrary to this expectation, our results revealed that adaptation to GPs is robust in early visual areas (V1, V2, and V3), but not in higher tier visual areas (V3AB and V4v), suggesting that form cues in oriented GPs are primarily derived from local-processing mechanisms that originate in V1. Finally, adaptation to vertically oriented GPs causes a modification in the BOLD response within early visual areas, regardless of the relative orientations of the adapting and test stimuli, indicating a lack of orientation selectivity.


Assuntos
Imageamento por Ressonância Magnética , Córtex Visual , Humanos , Adaptação Fisiológica/fisiologia , Aclimatação , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiologia , Neurônios , Estimulação Luminosa/métodos
6.
Vaccine ; 41(2): 294-303, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36464541

RESUMO

BACKGROUND: The Corona pandemic and ongoing mass vaccinations raise the question of the nocebo mechanisms involved. Since immunization is usually administered to healthy people as a preventive health measure, adverse events (AE) following immunization are less accepted and could contribute to vaccine hesitancy. Assuming that vaccinees experience nocebo responses, the aim of this meta-analysis was to investigate the effect sizes of solicited adverse events (or assumed reactogenicity) reported in placebo groups in RCTs on seasonal influenza vaccination. METHODS: Literature search via PubMed, Web of Science, and CENTRAL was conducted considering gray literature. Only RCTs with placebo groups using pharmacologically inert substances (like saline) were included. Quality was assessed using Cochrane Collaboration's Risk of Bias Tool. Effect sizes were estimated using a random mixed effects model based on k = 31 studies covering 14,326 participants in placebo groups. RESULTS: Reported solicited AEs in placebo groups showed significant effect sizes of proportions (ESp). In k = 13 analyzed placebo groups, 35 % of the participants reported at least one solicited systemic AE (p = 0.007). The most common particular solicited systemic AEs were headache (k = 27; 17 %; p = 0.001), malaise (k = 13; 12 %; p = 0.004), and hyperhidrosis (k = 4; 12 %; p < 0.001) within one week after vaccination. CONCLUSION: The results show significant solicited AEs in placebo groups, indicating substantial nocebo responses after vaccination. Based on the fact that most vaccination programs include similar groups of healthy people, we expect that comparable nocebo effects occur during other campaigns. Health care professionals should be aware of the nocebo response and take action to prevent or decrease the burden of adverse events following immunization. Fear of side effects must be addressed early in order to diminish vaccine hesitancy. Prospero identifier: CRD42020156287, October 2019.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Influenza Humana , Vacinação , Humanos , Grupos Controle , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Influenza Humana/prevenção & controle , Estações do Ano , Vacinação/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Curr Biol ; 32(23): 5022-5030.e7, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36384138

RESUMO

It is generally thought that children learn more efficiently than adults. One way to accomplish this is to have learning rapidly stabilized such that it is not interfered with by subsequent learning. Although γ-aminobutyric acid (GABA) plays an important role in stabilization, it has been reported that GABAergic inhibitory processing is not fully matured yet in children compared with adults. Does this finding indicate that more efficient learning in children is not due to more rapid stabilization? Here, we measured the concentration of GABA in early visual cortical areas in a time-resolved fashion before, during, and after visual perceptual learning (VPL) within subjects using functional MRS (fMRS) and then compared the concentrations between children (8 to 11 years old) and adults (18 to 35 years old). We found that children exhibited a rapid boost of GABA during visual training that persisted after training ended, whereas the concentration of GABA in adults remained unchanged. Moreover, behavioral experiments showed that children exhibited rapid development of resilience to retrograde interference, which indicates that children stabilize VPL much faster than adults. These results together suggest that inhibitory processing in children's brains is more dynamic and adapts more quickly to stabilize learning than in adults, making learning more efficient in children.


Assuntos
Aprendizagem , Córtex Visual , Ácido gama-Aminobutírico , Adolescente , Adulto , Criança , Humanos , Adulto Jovem , Ácido gama-Aminobutírico/fisiologia , Córtex Visual/fisiologia
8.
Electron Mark ; 32(4): 2381-2404, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36158525

RESUMO

Open government data (OGD) holds great potential for firms and the digital economy as a whole and has attracted increasing interest in research and practice in recent years. Governments and organizations worldwide are struggling in exploiting the full potential of OGD and require a comprehensive understanding of this phenomenon. Although scientific debates in OGD research are intense and heterogeneous, the field lacks theoretical integration of OGD topics and their systematic consideration in the context of the digital economy. In addition, OGD has been widely neglected by information systems (IS) research, which promises great potential for advancing our knowledge of the OGD concept and its role in the digital economy. To fill in this gap, this study conducts a systematic literature review of 169 empirical OGD studies. In doing so, we develop a theoretical review framework of Antecedents, Decisions, Outcomes (ADO) to unify and grasp the accumulating isolated evidence on OGD in context of the digital economy and provide a theory-informed research agenda to tap the potential of IS research for OGD. Our findings reveal six related key topic clusters of OGD research and substantial gaps, opening up prospective research avenues and particularly outlining how IS research can inform and advance OGD research. Supplementary information: The online version contains supplementary material available at 10.1007/s12525-022-00582-8.

9.
Ann Phys Rehabil Med ; 65(1): 101444, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33091614

RESUMO

BACKGROUND: Resting heart rate (HR) and HR variability (HRV) are known to predict mortality in patients after myocardial infarction (MI). OBJECTIVE: We assessed acute and chronic effects of high-intensity interval training (HIIT) versus moderate-intensity continuous exercise (MICE) on HR and HRV in individuals after acute ST-segment elevation MI (STEMI). METHODS: Participants within 7 weeks after MI were randomly assigned to HIIT or MICE groups for a 9-week intervention. HR and the power spectrum of HRV were measured pre- and post-intervention by using orthostatic challenge and during sleep to assess chronic effects. Sleep measurements were performed at night after HIIT, MICE or no training to assess acute effects. Mixed models assessed time*group interaction for differences in chronic and acute effects, adjusted for beta-blocker dose and number of training sessions. RESULTS: Overall, 34 of 37 and 35 of 36 participants in the HIIT and MICE groups completed the study. We found a trend for an acute increase in HR of 2.5 bpm (4%, P=0.023) during sleep after HIIT. We found a trend for a chronic decrease in HR during supine and standing position as well as during sleep in the MICE group but a trend for an increase in HR during supine and standing position in the HIIT group. Low- and high-frequency power (LF, HF) of the standing segment increased from pre- to post-intervention in the MICE group but decreased in the HIIT group (group*time interaction P=0.005 and P=0.026, respectively). CONCLUSION: HR during sleep tended to be increased acutely during the night after HIIT but not after MICE as compared with controls. Chronic effects on resting HR, HF and LF tended to be more beneficial after MICE than HIIT in individuals with recent STEMI.


Assuntos
Treinamento Intervalado de Alta Intensidade , Infarto do Miocárdio , Exercício Físico , Frequência Cardíaca , Humanos
10.
J Sci Med Sport ; 25(4): 281-286, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34895837

RESUMO

OBJECTIVES: Athletes performing sports on high level are at increased risk for sudden cardiac death. This includes paediatric athletes, even though data on screening strategies in this age group remain scarce. This study aimed to assess electrocardiogram interpretation criteria in paediatric athletes and to evaluate the cost of screening. METHODS: National, multicentre, retrospective, observational study on 891 athletes of paediatric age (<18 years) evaluated by history, physical examination and 12-lead electrocardiogram. The primary outcome measure was abnormal electrocardiogram findings according to the International Recommendations for Electrographic Interpretation in Athletes. The secondary outcome measure was cost of screening. RESULTS: 19 athletes (2.1%) presented abnormal electrocardiogram findings requiring further investigations, mainly abnormal T-wave inversion. These 19 athletes were predominantly males, performing endurance sports with a mean volume of 10 weekly hours for a mean duration of 6 years of training. Further investigations did not identify any relevant pathology. All athletes were cleared for competition with regular follow-up. Total costs of the screening were 108,860 USD (122 USD per athlete). CONCLUSIONS: Our study using the International Recommendations for Electrographic Interpretation in Athletes identified a low count of abnormal findings in paediatric athletes, yet raising substantially the cost of screening. Hence, the utility of electrocardiogram-inclusive screening of paediatric athletes remains to be elucidated by longitudinal data.


Assuntos
Cardiopatias , Adolescente , Atletas , Criança , Custos e Análise de Custo , Morte Súbita Cardíaca/prevenção & controle , Eletrocardiografia , Cardiopatias/diagnóstico , Humanos , Masculino , Estudos Retrospectivos , Suíça
11.
Int J Cardiol ; 340: 1-6, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34419529

RESUMO

BACKGROUND: The role of cardiac rehabilitation (CR) is well established in the secondary prevention of ischemic heart disease. Unfortunately, the participation rates across Europe remain low, especially in elderly. The EU-CaRE RCT investigated the effectiveness of a home-based mobile CR programme in elderly patients that were not willing to participate in centre-based CR. The initial study concluded that a 6-month home-based mobile CR programme was safe and beneficial in improving VO2peak when compared with no CR. OBJECTIVE: To assess whether a 6-month guided mobile CR programme is a cost-effective therapy for elderly patients who decline participation in CR. METHODS: Patients were enrolled in a multicentre randomised clinical trial from November 11, 2015, to January 3, 2018, and follow-up was completed on January 17, 2019, in a secondary care system with 6 cardiac institutions across 5 European countries. A total of 179 patients who declined participation in centre-based CR and met the inclusion criteria consented to participate in the European Study on Effectiveness and Sustainability of Current Cardiac Rehabilitation Programs in the Elderly trial. The data of patients (n = 17) that were lost in follow-up were excluded from this analysis. The intervention (n = 79) consisted of 6 months of mobile CR programme with telemonitoring, and coaching based on motivational interviewing to stimulate patients to reach exercise goals. Control patients did not receive any form of CR throughout the study period. The costs considered for the cost-effectiveness analysis of the RCT are direct costs 1) of the mobile CR programme, and 2) of the care utilisation recorded during the observation time from randomisation to the end of the study. Costs and outcomes (utilities) were compared by calculation of the incremental cost-effectiveness ratio. RESULTS: The healthcare utilisation costs (P = 0.802) were not significantly different between the two groups. However, the total costs were significantly higher in the intervention group (P = 0.040). The incremental cost-effectiveness ratio for the primary endpoint VO2peak at 6 months was €1085 per 1-unit [ml/kg/min] improvement in change VO2peak and at 12 months it was €1103 per 1 unit [ml/kg/min] improvement in change VO2peak. Big differences in the incremental cost-effectiveness ratios for the primary endpoint VO2peak at 6 months and 12 months were present between the adherent participants and the non-adherent participants. CONCLUSION: From a health-economic point of view the home-based mobile CR programme is an effective and cost-effective alternative for elderly cardiac patients who are not willing to participate in a regular rehabilitation programme to improve cardiorespiratory fitness. The change of QoL between the mobile CR was similar for both groups. Adherence to the mobile CR programme plays a significant role in the cost-effectiveness of the intervention. Future research should focus on the determinants of adherence, on increasing the adherence of patients and the implementation of comprehensive home-based mobile CR programmes in standard care.


Assuntos
Reabilitação Cardíaca , Telerreabilitação , Idoso , Análise Custo-Benefício , Exercício Físico , Humanos , Qualidade de Vida
12.
Comput Intell Neurosci ; 2021: 5573740, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34135951

RESUMO

This short survey reviews the recent literature on the relationship between the brain structure and its functional dynamics. Imaging techniques such as diffusion tensor imaging (DTI) make it possible to reconstruct axonal fiber tracks and describe the structural connectivity (SC) between brain regions. By measuring fluctuations in neuronal activity, functional magnetic resonance imaging (fMRI) provides insights into the dynamics within this structural network. One key for a better understanding of brain mechanisms is to investigate how these fast dynamics emerge on a relatively stable structural backbone. So far, computational simulations and methods from graph theory have been mainly used for modeling this relationship. Machine learning techniques have already been established in neuroimaging for identifying functionally independent brain networks and classifying pathological brain states. This survey focuses on methods from machine learning, which contribute to our understanding of functional interactions between brain regions and their relation to the underlying anatomical substrate.


Assuntos
Encéfalo , Imagem de Tensor de Difusão , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Relação Estrutura-Atividade
13.
J Magn Reson ; 323: 106889, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33518176

RESUMO

The characterisation of polymeric materials in their full complexity of chain length, monomeric composition, branching and functionalization is a tremendous challenge and is best tackled by tailored multi-dimensional coupled analytical and detection techniques. Herein, we focus on the improvement of an affordable but information rich 2D-method for polymer analysis: the online hyphenation of benchtop 1H NMR spectroscopy with size exclusion chromatography (SEC). The main benefit of this approach is correlated information of chain length (SEC) to chemical composition (1H NMR). Our setup combines SEC onflow with a benchtop NMR spectrometer at 43 or 62 MHz with chemical shift resolution as a robust detector. A detailed comparison of the two instruments is included considering, that only the 43 MHz instrument is equipped with a dedicated z-gradient enabling pulse sequences such as WET. The main challenge of this method is the very low concentration of species of interest after chromatographic separation. At typical SEC conditions, the analyte dilution is typically more than a factor of 1000:1 in a protonated solvent. Therefore, an efficient solvent signal suppression is needed. In this article, several suppression pulse sequences are explored like WET, WEFT, JNR and a simple one-pulse approach - some for the first time on this hardware. By choosing an optimal method, signal strength ratios of solvent to analyte of 1:1 or better are achievable on flow. To illustrate the broad range of possible applications, three typical cases of analyte to solvent signal proximity (no overlap, partial and full overlap) are discussed using typical polymers (PS, PMMA, PEMA) and solvents (chloroform and THF). For each case, several suppression methods are compared and evaluated using a set of numerical criteria (analyte signal suppression and broadening, solvent signal suppression, remaining solvent signal width).

14.
J Neurosci ; 41(9): 1970-1981, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33452222

RESUMO

Attending to a stimulus enhances the neuronal responses to it, while responses to nonattended stimuli are not enhanced and may even be suppressed. Although the neural mechanisms of response enhancement for attended stimuli have been intensely studied, the neural mechanisms underlying attentional suppression remain largely unknown. It is uncertain whether attention acts to suppress the processing in sensory cortical areas that would otherwise process the nonattended stimulus or the subcortical input to these cortical areas. Moreover, the neurochemical mechanisms inducing a reduction or suppression of neuronal responses to nonattended stimuli are as yet unknown. Here, we investigated how attention directed toward visual processing cross-modally acts to suppress vestibular responses in the human brain. By using functional magnetic resonance spectroscopy in a group of female and male subjects, we find that attention to visual motion downregulates in a load-dependent manner the concentration of excitatory neurotransmitter (glutamate and its precursor glutamine, referred to together as Glx) within the parietoinsular vestibular cortex (PIVC), a core cortical area of the vestibular system, while leaving the concentration of inhibitory neurotransmitter (GABA) in PIVC unchanged. This makes PIVC less responsive to excitatory thalamic vestibular input, as corroborated by functional magnetic resonance imaging. Together, our results suggest that attention acts to suppress the processing of nonattended sensory cues cortically by neurochemically rendering the core cortical area of the nonattended sensory modality less responsive to excitatory thalamic input.SIGNIFICANCE STATEMENT Here, we address a fundamental problem that has eluded attention research for decades, namely, how the brain ignores irrelevant stimuli. To date, three classes of solutions to this problem have been proposed: (1) enhancement of GABAergic interneuron activity in cortex, (2) downregulation of glutamatergic cell activity in cortex; and (3) downregulation of neural activity in thalamic projection areas, which would then provide the cortex with less input. Here, we use magnetic resonance spectroscopy in humans and find support for the second hypothesis, implying that attention to one sensory modality involves the suppression of irrelevant stimuli of another sensory modality by downregulating glutamate in the cortex.


Assuntos
Atenção/fisiologia , Córtex Cerebral/fisiologia , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Adulto , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Estimulação Luminosa , Percepção Visual/fisiologia , Adulto Jovem
15.
J Nutr Biochem ; 90: 108576, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33388346

RESUMO

This study compared the relative mRNA expression of all mammal zinc (Zn) transporter genes in selected tissues of weaned piglets challenged with short-term subclinical Zn deficiency (SZD). The dietary model involved restrictive feeding (450 g/animal*day-1) of a high-phytate diet (9 g/kg) supplemented with varying amounts of zinc from ZnSO4*7H2O ranging from deficient to sufficient supply levels (total diet Zn: 28.1, 33.6, 38.8, 42.7, 47.5, 58.2, 67.8, 88.0 mg Zn/kg). Total RNA preparations comprised jejunal and colonic mucosa as well as hepatic and nephric tissue. Statistical modelling involved broken-line regression (P≤.05). ZIP10 and ZIP12 mRNAs were not detected in any tissue and ZnT3 mRNA was only identified in the kidney. All other genes were expressed in all tissues but only a few gene expression patterns allowed a significant (P<.0001) fitting of broken-line regression models, indicating homeostatic regulation under the present experimental conditions. Interestingly, these genes could be subcategorized by showing significant turnarounds in their response patterns, either at ~40 or ~60 mg Zn/kg diet (P<.0001). In conclusion, the present study showed clear differences in Zn transporter gene expression in response to SZD compared to the present literature on clinical models. We recognized that certain Zn transporter genes were regulated under the present experimental conditions by two distinct homeostatic networks. For the best of our knowledge, this represents the first comprehensive screening of Zn transporter gene expression in a highly translational model to human physiology.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , RNA Mensageiro/metabolismo , Zinco/deficiência , Fenômenos Fisiológicos da Nutrição Animal , Animais , Colo/metabolismo , Dieta , Suplementos Nutricionais , Modelos Animais de Doenças , Feminino , Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Jejuno/metabolismo , Fígado/metabolismo , Masculino , Suínos , Desmame , Zinco/metabolismo
16.
Nanotechnology ; 31(50): 505714, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-32927451

RESUMO

Hybrid systems consisting of colloidal CdS/ZnS core/shell quantum dots on ZnSe semiconductor substrates have been studied by continuous-wave and nanosecond time-resolved photoluminescence. On the basis of kinetic calculations, we studied the interplay between the possible transfer processes in these hybrids. The considered transfer mechanisms were resonance energy transfer, photon reabsorption, electron and hole tunneling. Depending on the size of the CdS cores the dominating transfer mechanism is changing. Carrier tunneling was found only for quantum dots in direct contact to the substrate. For large quantum dots a hole tunneling was found, whereas in case of small dots the fast electron tunneling is decisive. Eventually, we were able to determine the conduction band offset between CdS and ZnSe to 0.56 eV at 10 K.

17.
Front Neurol ; 11: 483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582011

RESUMO

Placental and fetal hypoxia caused by perinatal hypoxic-ischemic events are major causes of stillbirth, neonatal morbidity, and long-term neurological sequelae among surviving neonates. Brain hypoxia and associated pathological processes such as excitotoxicity, apoptosis, necrosis, and inflammation, are associated with lasting disruptions in epigenetic control of gene expression contributing to neurological dysfunction. Recent studies have pointed to DNA (de)methylation, histone modifications, and non-coding RNAs as crucial components of hypoxic-ischemic encephalopathy (HIE). The understanding of epigenetic dysregulation in HIE is essential in the development of new clinical interventions for perinatal HIE. Here, we summarize our current understanding of epigenetic mechanisms underlying the molecular pathology of HI brain damage and its clinical implications in terms of new diagnostic, prognostic, and therapeutic tools.

18.
Arch Anim Nutr ; 74(1): 19-38, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31661317

RESUMO

Two trials were conducted with 48 newly weaned piglets (28 d old) each 8.6 ± 0.05 kg to study how Laminaria japonica plants (LJ) affect zootechnical performance, feed conversion and the apparent total tract digestibility (ATTD) of crude nutrients. All basal diets consisted of cereals, soybean meal, skim milk powder and premixes according to recommendations (no growth promoters or enzymes). For Trial 1, piglets from 16 litters (50% male-castrated, 50% female) were assigned to three treatment groups (n = 16) in a completely randomised block design. Groups received either 2.5% supplementation with sun dried (SD) or drum dried (DD) LJ powder or 2.5% of diatomaceous earth (control). For Trial 2, piglets from 12 litters received either 5% of diatomaceous earth (control) or one of three mixtures of diatomaceous earth + DD LJ powder (3.3%+1.7%, 1.7%+3.3% or 0.0%+5%; n = 12). Data collection included zootechnical performance, faecal consistency, blood plasma urea (Trial 1 and 2) and ATTD (Trial 2). Metabolisable energy (ME) of DD LJ and diets in Trial 2 was estimated using digestible nutrients. Statistical analysis included two-way ANOVA (treatment, block) and mixed linear regression. During both trials, LJ at dosages ≥2.5% significantly reduced feed:gain ratio compared to control (p ≤ 0.0001, = 0.01 for Trial 1, Trial 2) irrespective of the drying method. ATTD from Trial 2 significantly increased digestibilities of dry matter (DM) and crude ash (CA) (p ≤ 0.01) and significantly decreased digestibilities of organic matter and crude fibre in animals fed ≥3.33% DD LJ (p = 0.01). Fractional digestibility of the DD LJ resulted in limited ME of ~9.3 ± 2.5 MJ/kg DM. Dietary conversion ratios of ME and digestible DM of DD LJ diets from Trial 2 decreased linearly with increasing algal supplementation (R2 = 0.93, 0.94 and pslope = 0.002, 0.002 for MCR, DCR). In conclusion, dried LJ powder was included up to 5% into diets without impairing zootechnical performance. The improved feed conversion in the presence of LJ was partly due to slightly higher ME within the algae diets compared to control. However, piglets receiving LJ during Trial 2 needed significantly lower dietary ME and digestible DM to maintain growth performance. Thus, LJ exerted a performance enhancing effect on weaned piglets. The precise mode-of-action is yet unclear.


Assuntos
Digestão/efeitos dos fármacos , Laminaria/química , Sus scrofa/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Fezes/química , Feminino , Masculino , Distribuição Aleatória , Sus scrofa/sangue , Desmame
19.
J Cogn Neurosci ; 32(3): 484-496, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31682567

RESUMO

There is growing evidence that vestibular information is not only involved in reflexive eye movements and the control of posture but it also plays an important role in higher order cognitive processes. Previous behavioral research has shown that concomitant vestibular stimuli influence performance in tasks that involve imagined self-rotations. These results suggest that imagined and perceived body rotations share common mechanisms. However, the nature and specificity of these effects remain largely unknown. Here, we investigated the neural mechanisms underlying this vestibulocognitive interaction. Participants (n = 20) solved an imagined self-rotation task during caloric vestibular stimulation. We found robust main effects of caloric vestibular stimulation in the core region of the vestibular network, including the rolandic operculum and insula bilaterally, and of the cognitive task in parietal and frontal regions. Interestingly, we found an interaction of stimulation and task in the left inferior parietal lobe, suggesting that this region represents the modulation of imagined body rotations by vestibular input. This result provides evidence that the inferior parietal lobe plays a crucial role in the neural integration of mental and physical body rotation.


Assuntos
Imagem Corporal , Encéfalo/fisiologia , Imaginação/fisiologia , Vestíbulo do Labirinto/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/fisiologia , Tempo de Reação , Adulto Jovem
20.
J Zhejiang Univ Sci B ; 20(8): 617-627, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31273959

RESUMO

A major goal of mineral nutrition research is to provide information of feed zinc (Zn) utilization efficiency and gross Zn requirements as affected by changing rearing conditions. This can be achieved only by applying precise experimental models that acknowledge the basic principles of Zn metabolism. This review article summarizes the most important aspects of Zn homeostasis in monogastric species, including molecular aspects of Zn acquisition and excretion. Special emphasis is given to the role of the skeleton as well as the exocrine pancreas for animal Zn metabolism. Finally, we discuss consequences arising from these physiological principles for the experimental design of trials which aim to address questions of Zn requirements and bioavailability.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Disponibilidade Biológica , Pâncreas Exócrino/metabolismo , Zinco/metabolismo , Ração Animal , Animais , Dieta , Genótipo , Homeostase , Humanos , Minerais/metabolismo , Oligoelementos
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