RESUMO
Although it is often assumed that valence processing in the prefrontal cortex (PFC) is similar for stimuli originating from different sensory modalities, evidence supporting this view is lacking. To address this, we recruited 20 male participants and used a delayed-response fMRI design to test whether perceived pleasantness of flavors and images is similarly processed in the PFC. As predicted, significant correlations were observed between image and flavor pleasantness ratings, and PFC response to these stimuli; however, these responses were spatially different, with flavor pleasantness reflected in more ventrally located PFC regions than image pleasantness. These results indicate that, contrary to the general assumption of a singular circuit representing pleasantness, distinct PFC circuits are recruited depending upon stimulus modality. We argue that the ventral-dorsal distinction may be attributed to a difference in proximal versus distal stimulus representations.
Assuntos
Mapeamento Encefálico/métodos , Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Percepção Gustatória/fisiologia , Percepção Visual/fisiologia , Adolescente , Adulto , Emoções/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
A metallic taste is reported by cancer patients as a side effect of systemic therapy. Despite the high prevalence, this taste alteration has received limited attention. The present study investigated: 1) the prevalence of metallic taste in cancer patients treated with systemic therapy; 2) possible predictors of metallic taste; and 3) characteristics of metallic taste. A heterogeneous population of 127 cancer patients, who had received systemic treatment in the past year or were still on treatment, completed a questionnaire developed for this study. Fifty-eight of 127 (46%) patients reported taste changes in the preceding week. Of these patients, 20 (34%) reported a metallic taste. Patients treated with chemotherapy, concomitant radiotherapy, as well as targeted therapy reported metallic taste. Women experienced metallic taste more often than men. Patients experiencing a metallic taste also reported more frequently that they were bothered by sour food and that everything tasted bitter. The experience of metallic taste was highly variable among patients. In conclusion, metallic taste is a frequently experienced taste alteration by cancer patients. Patients treated with chemotherapy, concomitant radiotherapy, and targeted therapy are all at risk for this taste alteration. However, not all patients reported this alteration as bothersome.
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Antineoplásicos/efeitos adversos , Neoplasias/terapia , Radioterapia/efeitos adversos , Distúrbios do Paladar/etiologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/efeitos adversos , Inquéritos e Questionários , Distúrbios do Paladar/induzido quimicamenteRESUMO
BACKGROUND: Abnormal brain activations during processing of emotional facial expressions in depressed patients have been demonstrated. We investigated the natural course of brain activation in response to emotional faces in depression, indexed by functional magnetic resonance imaging (fMRI) scans preceding and following change in depressive state. We hypothesized a decrease in activation in the amygdala, anterior cingulate cortex (ACC), and insula with a decrease in depressive pathology. METHODS: A 2-year longitudinal fMRI study was conducted as part of the Netherlands Study of Depression and Anxiety. We included 32 healthy controls and 49 depressed patients. During the second scan, 27 patients were in remission (remitters), the other 22 were not (nonremitters). All participants viewed faces with emotional expressions during scanning. RESULTS: Rostral ACC activation during processing of happy faces was predictive of a decrease in depressive state (PFWE = .003). In addition, remitters showed decreased activation of the insula over time (PFWE = .016), specifically during happy faces. Nonremitters displayed increased abnormalities in emotion recognition circuitry during the second scan compared to the first. No effect of selective serotonin reuptake inhibitor use was observed. CONCLUSIONS: Our results demonstrate that rostral ACC activation may predict changes in depressive state even at 2-year outcome. The association between change in depressed state and change in insula activation provides further evidence for the role of the insula in a network maintaining emotional and motivational states.
Assuntos
Encéfalo/fisiopatologia , Transtorno Depressivo/fisiopatologia , Imageamento por Ressonância Magnética , Adulto , Mapeamento Encefálico , Transtorno Depressivo/psicologia , Emoções , Expressão Facial , Feminino , Humanos , Estudos Longitudinais , Masculino , Países BaixosRESUMO
PURPOSE: Oral nutritional supplements (ONS) are commonly prescribed to malnourished patients to improve their nutritional status. Taste and smell changes in patients with cancer can affect the palatability of ONS. The present study investigated: (1) the palatability of six ONS in testicular cancer patients before, during the first two cycles, and after chemotherapy; (2) the relation between the palatability and taste and smell function; (3) the metallic taste of these ONS. METHODS: Twenty-one testicular cancer patients undergoing first-line cisplatin-based chemotherapy participated. Two milk-based (vanilla; strawberry), two juice-based (apple; orange), and two yoghurt-based (vanilla-lemon; peach-orange) ONS were tested. A questionnaire was used to assess the palatability of ONS and to which extent the attribute 'metallic' was applicable. Taste and smell function were measured using taste strips and 'Sniffin' Sticks', respectively. RESULTS: The palatability of ONS was highly variable among patients. The milk-based strawberry ONS was preferred most before, during, and after chemotherapy. The liking of the milk-based vanilla ONS tended to decrease over time (p = 0.053), whereas the liking of the other ONS remained stable. A higher smell threshold and a lower sour taste threshold were correlated to a decreased liking of the milk-based vanilla ONS. The two juice-based ONS tended to taste more metallic during than before chemotherapy. CONCLUSION: Health care professionals and patients should be aware that the palatability of ONS can change over time. Regular structured contact between health care professionals and patients regarding the choice of ONS seems warranted.
Assuntos
Suplementos Nutricionais/análise , Desnutrição/prevenção & controle , Neoplasias Testiculares/terapia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: Chemotherapy can affect taste and smell function. This may contribute to the high prevalence of overweight and metabolic syndrome in testicular cancer survivors (TCS). Aims of the study were to evaluate taste and smell function and possible consequences for dietary intake, food preference, and body composition in TCS treated with cisplatin-based chemotherapy. METHODS: Fifty TCS, 1-7 years post-chemotherapy, and 50 age-matched healthy men participated. Taste and smell function were measured using taste strips and 'Sniffin' Sticks', respectively. Dietary intake was investigated using a food frequency questionnaire. Food preference was assessed using food pictures varying in taste (sweet/savoury) and fat or protein content. Dual-Energy X-ray Absorptiometry was performed to measure body composition. Presence of metabolic syndrome and hypogonadism were assessed. RESULTS: TCS had a lower total taste function, a higher bitter taste threshold, higher Body Mass Index (BMI), and more (abdominal) fat than controls (p < 0.05). No differences in smell function and dietary intake were found. Testosterone level was an important determinant of body composition in TCS (p = 0.016). CONCLUSION: Although taste function was impaired in TCS, this was not related to a different dietary intake compared to controls. Lower testosterone levels were associated with a higher BMI, fat mass, and abdominal fat distribution in TCS.
Assuntos
Composição Corporal , Sobreviventes de Câncer , Preferências Alimentares , Transtornos de Sensação/epidemiologia , Olfato/fisiologia , Paladar/fisiologia , Absorciometria de Fóton , Adolescente , Adulto , Glicemia/metabolismo , Comportamento de Escolha , Colesterol/sangue , Cisplatino/uso terapêutico , Estudos Transversais , Dieta , Seguimentos , Humanos , Hormônio Luteinizante/sangue , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/diagnóstico , Prevalência , Inquéritos e Questionários , Neoplasias Testiculares/tratamento farmacológico , Testosterona/sangue , Triglicerídeos/sangue , Adulto JovemRESUMO
The primary gustatory area is located in the insular cortex. Although the insular cortex has been the topic of multiple parcellation studies, its functional specialization regarding taste processing received relatively little attention. Studies investigating the brain response to taste suggested that the insular cortex is involved in processing multiple characteristics of a taste stimulus, such as its quality, intensity, and pleasantness. In the current functional magnetic resonance study, younger and older adult male subjects were exposed to four basic tastes in five increasing concentrations. We applied a data-driven analysis to obtain insular response maps, which showed that the insular cortex processes the presence of taste, its corresponding pleasantness, as well as its concentration. More specifically, the left and right insular cortices are differentially engaged in processing the aforementioned taste characteristics: representations of the presence of a taste stimulus as well as its corresponding pleasantness dominate in the left insular cortex, whereas taste concentration processing dominates in the right insular cortex. These results were similar across both age groups. Our results fit well within previous cytoarchitectural studies and show insular lateralization in processing different aspects of taste stimuli in men.
Assuntos
Córtex Cerebral/fisiologia , Percepção Gustatória/fisiologia , Adulto , Mapeamento Encefálico , Ácido Cítrico/administração & dosagem , Dominância Cerebral , Humanos , Imageamento por Ressonância Magnética , Masculino , Prazer/fisiologia , Quinina/administração & dosagem , Cloreto de Sódio/administração & dosagem , Sacarose/administração & dosagem , Adulto JovemRESUMO
Ageing affects taste perception as shown in psychophysical studies, however, underlying structural and functional mechanisms of these changes are still largely unknown. To investigate the neurobiology of age-related differences associated with processing of basic tastes, we measured brain activation (i.e. fMRI-BOLD activity) during tasting of four increasing concentrations of sweet, sour, salty, and bitter tastes in young (average 23 years of age) and older (average 65 years of age) adults. The current study highlighted age-related differences in taste perception at the different higher order brain areas of the taste pathway. We found that the taste information delivered to the brain in young and older adults was not different, as illustrated by the absence of age effects in NTS and VPM activity. Our results indicate that multisensory integration changes with age; older adults showed less brain activation to integrate both taste and somatosensory information. Furthermore, older adults directed less attention to the taste stimulus; therefore attention had to be reallocated by the older individuals in order to perceive the tastes. In addition, we considered that the observed age-related differences in brain activation between taste concentrations in the amygdala reflect its involvement in processing both concentration and pleasantness of taste. Finally, we state the importance of homeostatic mechanisms in understanding the taste quality specificity in age related differences in taste perception.
Assuntos
Envelhecimento , Encéfalo/fisiologia , Percepção Gustatória/fisiologia , Adolescente , Adulto , Idoso , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/fisiologia , Adulto JovemRESUMO
BACKGROUND: A recent study showed that tolvaptan, a vasopressin V2 receptor antagonist, decreased total kidney volume (TKV) growth and estimated glomerular filtration rate (GFR) loss in autosomal dominant polycystic kidney disease (ADPKD) with creatinine clearance≥60mL/min. The aim of our study was to determine whether the renal hemodynamic effects and pharmacodynamic efficacy of tolvaptan in ADPKD are dependent on GFR. STUDY DESIGN: Clinical trial with comparisons before and after treatment. SETTING & PARTICIPANTS: Patients with ADPKD with a wide range of measured GFRs (mGFRs; 18-148 mL/min) in a hospital setting. INTERVENTION: Participants were studied at baseline and after 3 weeks of treatment with tolvaptan given in increasing dosages, if tolerated (doses of 60, 90, and 120mg/d in weeks 1, 2, and 3, respectively). OUTCOMES: Change in markers for aquaresis (free-water clearance, urine and plasma osmolality, 24-hour urine volume, and plasma copeptin) and kidney injury (TKV and kidney injury biomarkers). MEASUREMENTS: GFR was measured by (125)I-iothalamate clearance; TKV, by magnetic resonance imaging; biomarker excretion, by enzyme-linked immunosorbent assay; and osmolality, by freezing point depression. RESULTS: In 27 participants (52% men; aged 46±10 years; mGFR, 69±39mL/min; TKV, 2.15 [IQR, 1.10-2.77] L), treatment with tolvaptan led to an increase in urine volume and free-water clearance and a decrease in urine osmolality, TKV, and kidney injury marker excretion. Changes in urine volume and osmolality with treatment were less in participants with lower baseline mGFRs (both P<0.01). However, change in fractional free-water clearance was greater at lower baseline mGFRs (P=0.001), suggesting that participants with decreased GFRs responded more to tolvaptan per functioning nephron. LIMITATIONS: Limited sample size, no control group. CONCLUSIONS: In patients with ADPKD with decreased kidney function, response to tolvaptan is lower for TKV, urinary volume, and osmolality, but larger for fractional free-water clearance. This latter finding suggests that patients with ADPKD with lower GFRs might benefit from long-term treatment with tolvaptan, as has been observed for patients with preserved GFRs.
Assuntos
Antagonistas dos Receptores de Hormônios Antidiuréticos/uso terapêutico , Benzazepinas/uso terapêutico , Taxa de Filtração Glomerular , Rim/patologia , Rim Policístico Autossômico Dominante/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Injúria Renal Aguda/metabolismo , Adulto , Biomarcadores/metabolismo , Estudos de Coortes , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Glicopeptídeos/sangue , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Concentração Osmolar , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/metabolismo , Estudos Prospectivos , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Índice de Gravidade de Doença , Tolvaptan , Resultado do TratamentoRESUMO
IMPORTANCE: Metformin treatment is associated with improved outcome after myocardial infarction in patients with diabetes. In animal experimental studies metformin preserves left ventricular function. OBJECTIVE: To evaluate the effect of metformin treatment on preservation of left ventricular function in patients without diabetes presenting with ST-segment elevation myocardial infarction (STEMI). DESIGN, SETTING, AND PARTICIPANTS: Double-blind, placebo-controlled study conducted among 380 patients who underwent primary percutaneous coronary intervention (PCI) for STEMI at the University Medical Center Groningen, The Netherlands, between January 1, 2011, and May 26, 2013. INTERVENTIONS: Metformin hydrochloride (500 mg) (n = 191) or placebo (n = 189) twice daily for 4 months. MAIN OUTCOMES AND MEASURES: The primary efficacy measure was left ventricular ejection fraction (LVEF) after 4 months, assessed by magnetic resonance imaging. A secondary efficacy measure was the N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration after 4 months. The incidence of major adverse cardiac events (MACE; the combined end point of death, reinfarction, or target-lesion revascularization) was recorded until 4 months as a secondary efficacy measure. RESULTS: At 4 months, all patients were alive and none were lost to follow-up. LVEF was 53.1% (95% CI, 51.6%-54.6%) in the metformin group (n = 135), compared with 54.8% (95% CI, 53.5%-56.1%) (P = .10) in the placebo group (n = 136). NT-proBNP concentration was 167 ng/L in the metformin group (interquartile range [IQR], 65-393 ng/L) and 167 ng/L in the placebo group (IQR, 74-383 ng/L) (P = .66). MACE were observed in 6 patients (3.1%) in the metformin group and in 2 patients (1.1%) in the placebo group (P = .16). Creatinine concentration (79 µmol/L [IQR, 70-87 µmol/L] vs 79 µmol/L [IQR, 72-89 µmol/L], P = .61) and glycated hemoglobin (5.9% [IQR, 5.6%-6.1%] vs 5.9% [IQR, 5.7%-6.1%], P = .15) were not significantly different between both groups. No cases of lactic acidosis were observed. CONCLUSIONS AND RELEVANCE: Among patients without diabetes presenting with STEMI and undergoing primary PCI, the use of metformin compared with placebo did not result in improved LVEF after 4 months. The present findings do not support the use of metformin in this setting. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01217307.
Assuntos
Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Disfunção Ventricular Esquerda/prevenção & controle , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/fisiopatologia , Intervenção Coronária Percutânea , Resultado do TratamentoRESUMO
Associative emotional learning, which is important for the social emotional functioning of individuals and is often impaired in psychiatric illnesses, is in part mediated by dopamine and glutamate pathways in the brain. The protein DARPP-32 is involved in the regulation of dopaminergic and glutaminergic signaling. Consequently, it has been suggested that the haplotypic variants of the gene PPP1R1B that encodes DARPP-32 are associated with working memory and emotion processing. We hypothesized that PPP1R1B should have a significant influence on the network of brain regions involved in associative emotional learning that are rich in DARPP-32, namely the striatum, prefrontal cortex (comprising the medial frontal gyrus and inferior frontal gyrus (IFG)), amygdala and parahippocampal gyrus (PHG). Dynamic causal models were applied to functional MRI data to investigate how brain connectivity during an associative emotional learning task is affected by different single-nucleotide polymorphisms (SNPs) of PPP1R1B: rs879606, rs907094 and rs3764352. Compared to heterozygotes, homozygotes with GTA alleles displayed increased intrinsic connectivity between the IFG and PHG, as well as increased excitability of the PHG for negative emotional stimuli. We have also elucidated the directionality of these genetic influences. Our data suggest that homozygotes with GTA alleles involve stronger functional connections between brain areas in order to maintain activation of these regions. Homozygotes might engage a greater degree of motivational learning and integration of information to perform the emotional learning task correctly. We conclude that PPP1R1B is associated with the neural network involved in associative emotional learning.
Assuntos
Aprendizagem por Associação/fisiologia , Fosfoproteína 32 Regulada por cAMP e Dopamina/genética , Emoções/fisiologia , Rede Nervosa/fisiologia , Adulto , Feminino , Variação Genética/genética , Humanos , Masculino , Adulto JovemRESUMO
Studying individuals who recently experienced a romantic reltionship breakup allows us to investigate mood disturbances in otherwise healthy individuals. In our study, we aimed to identify distinct depressive symptom trajectories following breakup and investigate whether these trajectories relate to personality traits and cognitive control. Subjects (n = 87) filled out questionnaires (RRS-NL-EXT trait rumination and NEO-FFI neuroticism) and performed cognitive tasks (trail making test, Stroop task) during a period of 30 weeks. To identify distinct depressive symptom trajectories ('trajectory groups'), we performed K-means clustering on the consecutive (assessed every 2 weeks) Major Depression Inventory scores. This resulted in four trajectory groups; 'resilience', 'fast recovery', 'slow recovery' and 'chronic distress'. The 'slow recovery group' and the 'chronic distress group' were found to have higher neuroticism and trait rumination levels compared to the 'resilience group', and the 'chronic distress group' also had higher neuroticism levels than the 'fast recovery group'. Moreover, the 'chronic distress group' showed worse overall trail making test performance than the 'resilience group'. Taken together, our findings show that distinct patterns of depressive symptom severity can be observed following breakup and that personality traits and cognitive flexibility seem to play a role in these depressive symptom patterns.
Assuntos
Depressão , Transtorno Depressivo Maior , Cognição , Depressão/psicologia , Humanos , Neuroticismo , Personalidade , Inquéritos e QuestionáriosRESUMO
Experiencing stress can have a disadvantageous effect on mental well-being. Additional to the relation between suffering from chronic stress and depression, both stress (acute and chronic) and depression are associated with cognitive alterations, including working memory. The breakup of a relationship is considered to be a stressful event that can lead to symptoms of depression in otherwise healthy people. Additional to elevated depression scores, stress-related cognitive alterations may occur in this population as well. Therefore, in the present fMRI study we investigated whether experiencing a relationship breakup is associated with working memory alterations and whether this is related to depressive symptom severity. A three workload version of the n-back task (0-back, 1-back, 2-back) was used to measure working memory in subjects who experienced a breakup in the preceding 6 months ("heartbreak group", n = 70) and subjects in a romantic relationship ("relationship group", n = 46). Behavioral task performance was compared between the two groups. Functional MRI scans were analyzed using General Linear Model (GLM) activation analyses. Workload conditions were contrasted to each other and to baseline and group differences were assessed. To investigate whether brain networks are associated with depressive symptom severity within the heartbreak group specifically, a post hoc feature-based Independent Component Analysis was performed on the 2-back > 0-back contrast images to identify brain regions that covaried across subjects. Behaviorally, the heartbreak group performed similar at high workload (i.e., 2-back) and better at moderate workload (i.e., 1-back) than the relationship group. GLM analysis revealed an interaction between group and 2-back > 0-back, 2-back > 1-back and 2-back > baseline; the heartbreak group showed less precuneus activation compared to the relationship group. Furthermore, within the heartbreak group, we found a negative association between depressive symptom severity and a brain network representing mostly the precuneus, anterior cingulate gyrus and supplementary motor cortex. Our findings suggest that the effect of a breakup is accompanied by workload-dependent working memory alterations. Therefore, we propose that this population can potentially be used to investigate the interplay between stress, cognitive functioning and depression.
RESUMO
Studies show that sex plays a role in stress-related depression, with women experiencing a higher vulnerability to its effect. Two major targets of antidepressants are brain-derived neurotrophic factor (BDNF) and cyclic adenosine monophosphate response element-binding protein (CREB). The aim of this study was to investigate the levels of CREB, phosphorylation of CREB (pCREB), and BDNF in stress-related brain regions of male and female rats after stress and recovery. CREB and pCREB levels were examined in CA1, CA2, CA3, paraventricular nucleus of the thalamus (PVT), amygdala, anterior cingulate area, dorsal part (ACAd), and infralimbic area of prefrontal cortex (PFC), whereas dentate gyrus (DG) and prelimbic area (PL) of PFC were examined for BDNF levels. Our results demonstrate that levels of CREB and pCREB in male CA1, CA2 and CA3, PVT, amygdala, and ACAd were reduced by stress, whereas the same brain regions of female rats exhibited no change. BDNF levels were decreased by chronic stress in female PL but were increased by acute stress in female DG. BDNF levels in male DG and PL were found not to undergo change in response to stress. Abnormalities in morphology occurred after chronic stress in males but not in females. In all cases, the levels of CREB, pCREB, and BDNF in recovery animals were comparable to the levels of these proteins in control animals. These findings demonstrate a sexual dimorphism in the molecular response to stress and suggest that these differences may have important implications for potential therapeutic treatment of depression.
Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Recuperação de Função Fisiológica , Estresse Psicológico/metabolismo , Doença Aguda , Animais , Proteína de Ligação a CREB , Feminino , Masculino , Plasticidade Neuronal , Ratos , Ratos Wistar , Fatores Sexuais , Distribuição TecidualRESUMO
Brain function depends on the flexible and dynamic coordination of functional subsystems within distributed neural networks operating on multiple scales. Recent progress has been made in the characterization of functional connectivity (FC) at the whole-brain scale from a dynamic, rather than static, perspective, but its validity for cognitive sciences remains under debate. Here, we analyzed brain activity recorded with functional Magnetic Resonance Imaging from 71 healthy participants evaluated for depressive symptoms after a relationship breakup based on the conventional Major Depression Inventory (MDI). We compared both static and dynamic FC patterns between participants reporting high and low depressive symptoms. Between-group differences in static FC were estimated using a standard pipeline for network-based statistic (NBS). Additionally, FC was analyzed from a dynamic perspective by characterizing the occupancy, lifetime, and transition profiles of recurrent FC patterns. Recurrent FC patterns were defined by clustering the BOLD phase-locking patterns obtained using leading eigenvector dynamics analysis (LEiDA). NBS analysis revealed a brain subsystem exhibiting significantly lower within-subsystem correlation values in more depressed participants (high MDI). This subsystem predominantly comprised connections between regions of the default mode network (i.e., precuneus) and regions outside this network. On the other hand, LEiDA results showed that high MDI participants engaged more in a state connecting regions of the default mode, memory retrieval, and frontoparietal network (p-FDR = 0.012); and less in a state connecting mostly the visual and dorsal attention systems (p-FDR = 0.004). Although both our analyses on static and dynamic FC implicate the role of the precuneus in depressive symptoms, only including the temporal evolution of BOLD FC helped to disentangle over time the distinct configurations in which this region plays a role. This finding further indicates that a holistic understanding of brain function can only be gleaned if the temporal dynamics of FC is included.
Assuntos
Encéfalo/diagnóstico por imagem , Depressão/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/fisiopatologia , Rede de Modo Padrão/diagnóstico por imagem , Rede de Modo Padrão/fisiopatologia , Depressão/fisiopatologia , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Visuais/diagnóstico por imagem , Vias Visuais/fisiopatologia , Adulto JovemRESUMO
Depressive symptoms following a stressful life event, such as a relationship breakup, are common, and constitute a potent risk factor for the onset of a major depressive episode. Resting-state neuroimaging studies have increasingly identified abnormal whole-brain communication in patients with depression, but it is currently unclear whether depressive symptoms in individuals without a clinical diagnosis have reliable neural underpinnings. We investigated to what extent the severity of depressive symptoms in a non-clinical sample was associated with imbalances in the complex dynamics of the brain during rest. To this end, a novel intrinsic ignition approach was applied to resting-state neuroimaging data from sixty-nine participants with varying degrees of depressive symptoms following a relationship breakup. Ignition-based measures of integration, hierarchy, and metastability were calculated for each participant, revealing a negative correlation between these measures and depressive ratings. We found that the severity of depressive symptoms was associated with deficits in the brain's capacity to globally integrate and process information over time. Furthermore, we found that increased depressive symptoms were associated with reduced spatial diversity (i.e., hierarchy) and reduced temporal variability (i.e., metastability) in the functional organization of the brain. These findings suggest the merit of investigating constrained dynamical complexity as it is sensitive to the level of depressive symptoms even in a non-clinical sample.
Assuntos
Encéfalo/fisiopatologia , Depressão/fisiopatologia , Depressão/psicologia , Transtorno Depressivo Maior/fisiopatologia , Adolescente , Adulto , Mapeamento Encefálico/métodos , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Neuroimagem/métodos , Descanso/psicologia , Adulto JovemRESUMO
Women show a higher prevalence for depression than men. However, the biological basis of gender differences in stress response and recovery still remain poorly understood. Therefore, the aim of the study was to assess the gender differences in response to acute stress, chronic stress and recovery in rats. Our results showed that stress decreased male body weight but had no effect on female rats. Open field test demonstrated behavioral changes in grooming and velocity after chronic stress and recovery. Increased activity of hypothalamic-pituitary-adrenocortical axis was reflected by adrenal hypertrophy and increase of plasma corticosterone levels except in the socially housed female rats after stress. Gender and brain region differences in response to stress and recovery were found in the expression of cAMP response element-binding protein (CREB) and phosphorylated CREB (pCREB). On the whole, expression of CREB and pCREB in male dentate gyrus (DG) and prefrontal cortex (PFC) was sensitive but in female DG and PFC it was resistant to acute and chronic stress. Interestingly, recovery restored the measured parameters to the normal level in male rats but not in female rats. In conclusion, these results suggest that male and female rats responded to stress and recovery in a different way.
Assuntos
Giro Denteado/fisiopatologia , Atividade Motora/fisiologia , Córtex Pré-Frontal/fisiopatologia , Estresse Psicológico/fisiopatologia , Animais , Corticosterona/sangue , Eletrochoque , Feminino , Masculino , Estimulação Luminosa , Ratos , Ratos WistarRESUMO
The occurrence of a stressful event is considered to increase the risk of developing depression. In the present study we explore whether the breakup of a romantic relationship can be used as an experimental model to study a depression-like state during a period of stress in individuals without a psychiatric disorder. The primary aim of our study was to investigate: 1) whether individuals with a recent romantic relationship breakup (''heartbreak") demonstrate symptoms of depression, 2) how to describe heartbreak characteristics based on data from a comprehensive questionnaire battery, and 3) whether this description can capture severity of depression symptoms. Secondary, we were interested in gender differences with regard to the above study objectives. Subjects who have experienced a relationship breakup in the preceding six months (N = 71) or are in a romantic relationship (N = 46) participated in our study. A questionnaire battery was administered to acquire information related to depression, mood, the breakup and (former) relationship. Principal Component Analysis with Procrustes bootstrapping was performed to extract components from the questionnaire data. Even though our sample of individuals who recently have experienced a relationship breakup can be on average considered non-depressed, group-level depression scores were elevated compared to individuals in a relationship (p = .001) and 26.8% reported symptoms corresponding to mild, moderate or severe depression. We described heartbreak by two principal components interpreted as ''sudden loss" and ''lack of positive affect", respectively. Highly significant correlations between the component scores and depression scores were found (p < .001 and p < .001, respectively), although these correlations differed between the genders. Based on these findings, we propose that the experience of a romantic relationship breakup is a viable experimental model to examine symptoms of depression in individuals without a psychiatric disorder. This way, stress-related coping and depression vulnerability can be studied in further research.
Assuntos
Afeto/fisiologia , Depressão/psicologia , Transtorno Depressivo/psicologia , Adaptação Psicológica/fisiologia , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Relações Interpessoais , Amor , Masculino , Modelos Teóricos , Adulto JovemRESUMO
PURPOSE: In ADPKD patients total kidney volume (TKV) measurement using MRI is performed to predict rate of disease progression. Historically T1 weighted images (T1) were used, but the methodology of T2 weighted imaging (T2) has evolved. We compared the performance of both sequences. METHODS: 40 ADPKD patients underwent an abdominal MRI at baseline and follow-up. TKV was measured by manual tracing with Analyze Direct 11.0 software. Three readers established intra- and interreader coefficients of variation (CV). T1 and T2 measured kidney volumes and growth rates were compared with ICC and Bland-Altman analyses. RESULTS: Participants were 49.7 ± 7.0 years of age, 55.0% female, with estimated GFR of 50.1 ± 11.5 mL/min/1.73 m2. CVs were low and comparable for T2 and T1 (intrareader: 0.83% [0.48-1.79] vs. 1.15% [0.34-1.77], P = 0.9, interreader: 2.18% [1.59-2.61] vs. 1.69% [1.07-3.87], P = 0.9). TKV was clinically similar, but statistically significantly different between T2 and T1: 1867 [1172-2721] vs. 1932 [1180-2551] mL, respectively (P = 0.006), with a bias of only 0.8% and high agreement (ICC 0.997). Percentage kidney growth during 2.2 ± 0.3 years was similar for T2 and T1 (9.3 ± 10.6% vs. 7.8 ± 9.9%, P = 0.1, respectively), with a bias of 1.5% and high agreement (ICC 0.843). T2 was more often of sufficient quality for volume measurement (86.7% vs. 71.1%, P < 0.001). CONCLUSIONS: In patients with ADPKD, measurement of kidney volume and growth rate performs similarly when using T2 compared to T1 weighted images, although T2 performs better on secondary outcome parameters; they are more often of sufficient quality for volume measurement and result in slightly lower intra- and interreader variability.
Assuntos
Rim/diagnóstico por imagem , Rim/patologia , Imageamento por Ressonância Magnética/métodos , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Rim Policístico Autossômico Dominante/patologia , Adolescente , Adulto , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Adulto JovemRESUMO
The ventral emotion network-encompassing the amygdala, insula, ventral striatum, and ventral regions of the prefrontal cortex-has been associated with the identification of emotional significance of perceived external stimuli and the production of affective states. Functional magnetic resonance imaging (fMRI) studies investigating chemosensory stimuli have associated parts of this network with pleasantness coding. In the current study, we independently analyzed two datasets in which we measured brain responses to flavor stimuli in young adult men. In the first dataset, participants evaluated eight regular off the shelf drinking products while participants evaluated six less familiar oral nutritional supplements (ONS) in the second dataset. Participants provided pleasantness ratings 20 seconds after tasting. Using independent component analysis (ICA) and mixed effect models, we identified one brain network in the regular products dataset that was associated with flavor pleasantness. This network was very similar to the ventral emotion network. Although we identified an identical network in the ONS dataset using ICA, we found no linear relation between activation of any network and pleasantness scores within this dataset. Our results indicate that flavor pleasantness is processed in a network encompassing amygdala, ventral prefrontal, insular, striatal and parahippocampal regions for familiar drinking products. For more unfamiliar ONS products the association is not obvious, which could be related to the unfamiliarity of these products.
Assuntos
Encéfalo/fisiologia , Emoções/fisiologia , Preferências Alimentares/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Paladar/fisiologia , Estriado Ventral/fisiologia , Adulto , Mapeamento Encefálico , Aromatizantes/administração & dosagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
BACKGROUND & AIMS: Taste and smell changes due to chemotherapy may contribute to the high prevalence of overweight in testicular cancer patients (TCPs). This study investigates the taste and smell function, dietary intake, food preference, and body composition in TCPs before, during, and up to 1 year after cisplatin-based chemotherapy. METHODS: Twenty-one consecutive TCPs participated. At baseline TCPs were compared to healthy controls (N = 48). Taste strips and 'Sniffin' Sticks' were used to determine psychophysical taste and smell function. Subjective taste, smell, appetite, and hunger were assessed using a questionnaire. Dietary intake was analyzed using a food frequency questionnaire. Food preference was assessed using food pictures varying in taste (sweet/savoury) and fat or protein content. A Dual-Energy X-ray Absorptiometry (DEXA) scan was performed to measure whole body composition. RESULTS: Compared to controls, TCPs had a lower smell threshold (P = 0.045) and lower preference for high fat sweet foods at baseline (P = 0.024). Over time, intra-individual psychophysical taste and smell function was highly variable. The salty taste threshold increased at completion of chemotherapy compared to baseline (P = 0.006). A transient decrease of subjective taste, appetite, and hunger feelings was observed per chemotherapy cycle. The percentage of fat mass increased during chemotherapy compared to baseline, while the lean mass and bone density decreased (P < 0.05). CONCLUSIONS: Coping strategies regarding subjective taste impairment should especially be provided during the first week of each chemotherapy cycle. Since the body composition of TCPs already had changed at completion of chemotherapy, intervention strategies to limit the impact of cardiovascular risk factors should probably start during treatment.