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1.
Nat Rev Drug Discov ; 23(5): 365-380, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565913

RESUMO

Prodrugs are derivatives with superior properties compared with the parent active pharmaceutical ingredient (API), which undergo biotransformation after administration to generate the API in situ. Although sharing this general characteristic, prodrugs encompass a wide range of different chemical structures, therapeutic indications and properties. Here we provide the first holistic analysis of the current landscape of approved prodrugs using cheminformatics and data science approaches to reveal trends in prodrug development. We highlight rationales that underlie prodrug design, their indications, mechanisms of API release, the chemistry of promoieties added to APIs to form prodrugs and the market impact of prodrugs. On the basis of this analysis, we discuss strengths and limitations of current prodrug approaches and suggest areas for future development.


Assuntos
Pró-Fármacos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Humanos , Animais , Desenho de Fármacos , Desenvolvimento de Medicamentos/métodos
3.
Phys Chem Chem Phys ; 26(3): 2035-2043, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38126539

RESUMO

Model systems are widely used in biology and chemistry to gain insight into more complex systems. In the field of computational chemistry, researchers use host-guest systems, relatively simple exemplars of noncovalent binding, to train and test the computational methods used in drug discovery. Indeed, host-guest systems have been developed to support the community-wide blinded SAMPL prediction challenges for over a decade. While seeking new host-guest systems for the recent SAMPL9 binding prediction challenge, which is the focus of the present PCCP Themed Collection, we identified phenothiazine as a privileged scaffold for guests of ß cyclodextrin (ßCD) and its derivatives. Building on this observation, we used calorimetry and NMR spectroscopy to characterize the noncovalent association of native ßCD and three methylated derivatives of ßCD with five phenothiazine drugs. The strongest association observed, that of thioridazine and one of the methyl derivatives, exceeds the well-known high affinity of rimantidine with ßCD. Intriguingly, however, methylation of ßCD at the 3 position abolished detectible binding for all of the drugs studied. The dataset has a clear pattern of entropy-enthalpy compensation. The NMR data show that all of the drugs position at least one aromatic proton at the secondary face of the CD, and most also show evidence of deep penetration of the binding site. The results of this study were used in the SAMPL9 blinded binding affinity-prediction challenge, which are detailed in accompanying papers of the present Themed Collection. These data also open the phenothiazines and, potentially, chemically similar drugs, such as the tricyclic antidepressants, as relatively potent binders of ßCD, setting the stage for future SAMPL challenge datasets and for possible applications as drug reversal agents.


Assuntos
Ciclodextrinas , Ciclodextrinas/química , Fenotiazinas , Sítios de Ligação , Termodinâmica
4.
J Cheminform ; 15(1): 101, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37885017

RESUMO

Established molecular machine learning models process individual molecules as inputs to predict their biological, chemical, or physical properties. However, such algorithms require large datasets and have not been optimized to predict property differences between molecules, limiting their ability to learn from smaller datasets and to directly compare the anticipated properties of two molecules. Many drug and material development tasks would benefit from an algorithm that can directly compare two molecules to guide molecular optimization and prioritization, especially for tasks with limited available data. Here, we develop DeepDelta, a pairwise deep learning approach that processes two molecules simultaneously and learns to predict property differences between two molecules from small datasets. On 10 ADMET benchmark tasks, our DeepDelta approach significantly outperforms two established molecular machine learning algorithms, the directed message passing neural network (D-MPNN) ChemProp and Random Forest using radial fingerprints, for 70% of benchmarks in terms of Pearson's r, 60% of benchmarks in terms of mean absolute error (MAE), and all external test sets for both Pearson's r and MAE. We further analyze our performance and find that DeepDelta is particularly outperforming established approaches at predicting large differences in molecular properties and can perform scaffold hopping. Furthermore, we derive mathematically fundamental computational tests of our models based on mathematical invariants and show that compliance to these tests correlates with overall model performance - providing an innovative, unsupervised, and easily computable measure of expected model performance and applicability. Taken together, DeepDelta provides an accurate approach to predict molecular property differences by directly training on molecular pairs and their property differences to further support fidelity and transparency in molecular optimization for drug development and the chemical sciences.

5.
Pharmacol Res Perspect ; 10(6): e01026, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36398492

RESUMO

The most recent consensus guidelines for dosing and monitoring vancomycin recommended the use of area-under-the-curve with Bayesian estimation for therapeutic monitoring. As this is a modern concept in the practice of clinical pharmacy, the main objective of this review is to introduce the fundamentals of Bayesian estimation and its mathematical application as it relates to vancomycin therapeutic drug monitoring. In addition, we aim to identify pharmacokinetic (PK) software programs that incorporate Bayesian estimation for vancomycin dosing and to describe the PK models utilized in those software programs for the adult population. Twelve software programs that utilize Bayesian estimation were identified, which included: Adult and Pediatric Kinetics, Best Dose, ClinCalc, DoseMeRx, ID-ODS, InsightRx, MwPharm++, NextDose, PrecisePK, TDMx, Tucuxi, and VancoCalc. The software programs varied in the population PK models used as the Bayesian a priori. With the presence of various vancomycin Bayesian software programs, it is important to choose those that utilize PK models reflective of the specific patient population.


Assuntos
Farmácia , Vancomicina , Adulto , Humanos , Criança , Vancomicina/farmacocinética , Teorema de Bayes , Antibacterianos/uso terapêutico , Monitoramento de Medicamentos/métodos
6.
J Natl Compr Canc Netw ; 20(9): 966-971, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36075388

RESUMO

Glioblastoma (GBM) is a malignant central nervous system neoplasm that remains largely incurable. Limited treatment options currently exist after disease progression on standard-of-care first-line therapy. However, repurposing the use of approved therapies in patients with potentially targetable genomic alterations continues to be an emerging area of interest. This report presents the first description of a patient with isocitrate dehydrogenase wild-type GBM with an underlying RET amplification who demonstrated a near-complete response while receiving therapy with the RET inhibitor selpercatinib. The case highlights the excellent blood-brain barrier penetration of selpercatinib, as well as its potential role in the management of RET-amplified GBM. Larger biomarker-enriched studies are needed to confirm the results of this case report. Given the rare incidence of RET alterations in GBM, findings from this report can help guide and support optimal treatment strategies for patients with RET-altered GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Proteínas Proto-Oncogênicas c-ret/genética , Pirazóis , Piridinas
7.
J Wound Care ; 31(Sup7): S30-S40, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35797248

RESUMO

OBJECTIVE: Hard-to-heal wounds are a common problem, worsened by ageing, and the increased prevalence of diabetes and morbid obesity. The provider-patient relationship has undergone a transformation, from a paternalistic to a mutual participation model, in which 'the physician tries to enter the patient's world to see the illness through the patient's eyes'. The indepth assessment of the impact of psychosocial, physical issues and provider-patient dynamics is crucial to wound healing and patient wellbeing. It can customise future treatment including physical therapy, psychological and social interventions to improve outcomes. METHOD: A new health-related quality of life instrument (HRQOL) proposal based on a survey consisting of 20 questions was completed by patients as a pilot project. The psychosocial, physical and provider-patient dynamics were evaluated. A total wound impact score (WIs) was tabulated, ranging from 20-80 points. A wound assessment and plan (PBW-AP) was created. RESULTS: In our sample of 25 patients, 75% experienced a moderate WIs (50-69) and 5% experienced a severe WIs (31-49). Feeling angry about having a wound was reported by 40% of patients. A majority of patients (60%) thought about their wounds >1 hour per day. Importantly, 24% answered that their primary care physicians never mentioned their wounds. CONCLUSION: It is important for all physicians taking care of patients with hard-to-heal wounds to see 'the patient behind the wound'. The PBW-AP algorithm is an individualised, multidisciplinary assessment and intervention based on a WIs. It is designed not only to identify but also to tackle psychosocial, physical, and provider-patient issues, to improve overall quality of life, patient satisfaction and clinical outcomes. Based on the results, the PBW-AP algorithm was designed to be used at initial and subsequent visits as a roadmap for problem identification and intervention.


Assuntos
Qualidade de Vida , Higiene da Pele , Humanos , Projetos Piloto , Inquéritos e Questionários , Cicatrização
8.
JAMA Otolaryngol Head Neck Surg ; 148(5): 436-445, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35389456

RESUMO

Importance: Olfactory impairment is highly prevalent and associated with multiple comorbidities, including neurodegenerative, cardiovascular, nutritional, and immune disorders. However, epidemiologic associations between olfactory impairment and mortality are discordant. Objective: To systematically clarify the epidemiologic associations between olfactory impairment and mortality. Data Sources: The PubMed, Embase, and Cochrane Library databases were searched from inception to August 13, 2021. Study Selection: Two blinded reviewers selected observational studies published as full-length, English-language articles in peer-reviewed journals that reported the presence or severity of chronic olfactory impairment, whether objectively measured or self-reported, in association with any mortality estimate, among adults aged 18 years or older. Data Extraction and Synthesis: Two reviewers independently extracted data, evaluated study bias using the Newcastle-Ottawa Scale, and appraised the quality of the evidence using the Grading of Recommendations Assessment, Development and Evaluation framework, following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and a PROSPERO-registered protocol. Maximally adjusted estimates were pooled using mixed-effects models, heterogeneity was measured using I2 statistics, sources of heterogeneity were investigated using meta-regression and subgroup meta-analyses, and publication bias was qualitatively and quantitatively assessed. Main Outcomes and Measures: Hazard ratios for all-cause mortality. Results: One retrospective cohort study and 10 prospective cohort studies (with a total of 21 601 participants) from 1088 nonduplicated records were included. Ten studies had a low risk of bias, whereas 1 study had a moderate risk; exclusion of the latter did not alter conclusions. Nine studies were included in the meta-analysis. Olfactory loss was associated with a significantly higher pooled hazard of all-cause mortality (hazard ratio, 1.52; 95% CI, 1.28-1.80; I2 = 82%). Meta-regression sufficiently explained heterogeneity, with longer mean follow-up duration weakening the pooled association, accounting for 91.3% of heterogeneity. Self-reported and objective effect sizes were similar. Associations were robust to trim-and-fill adjustment and the Egger test for publication bias. The overall quality of evidence was moderate. Conclusions and Relevance: The findings of this systematic review and meta-analysis suggest that olfactory impairment is associated with all-cause mortality and may be a marker of general health and biological aging. Further research is required to establish the underlying mechanisms and the scope for interventions.


Assuntos
Transtornos do Olfato , Comorbidade , Humanos , Transtornos do Olfato/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Risco
9.
Early Child Educ J ; 50(8): 1429-1438, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34629842

RESUMO

The practice of shared book reading is a nurturing support for early language, literacy, and socio-emotional development within young children's typical care. However, the closures of childcare, early education programs, and centers for family activities in the Spring of 2020 due to COVID-19 brought many sudden changes to the everyday lives of families with young children. In order to explore the impact of COVID-19 on shared reading, we surveyed parents of children between the ages of 2 and 5 (n = 85) about their children's frequency of shared reading engagement in February and October, 2020 as well as the frequency of screen-mediated reading, the number of readers their children read with, and book preferences at both time points. Parents were also asked about changes in their children's regular care and whether and how they had tried new kinds of (virtual) literacy activities during their increased time at home. Findings showed that there were no significant changes in frequency of shared reading from February to October, but there was a significant increase in frequency of screen-mediated reading, especially among families who lost outside-the-home childcare. There was also a significant decrease in the number of adults regularly reading with the children. Caregivers described adapting to virtual options for storytime. Ultimately, while families were still able to provide consistent amounts of shared reading with their children throughout COVID-19, the nature of that shared reading was changed. Future research will investigate whether these changes may have an impact on children's typical learning from shared reading.

10.
Cells ; 10(10)2021 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-34685753

RESUMO

Cancer stem cells, in contrast to their more differentiated daughter cells, can endure genotoxic insults, escape apoptosis, and cause tumor recurrence. Understanding how normal adult stem cells survive and go to quiescence may help identify druggable pathways that cancer stem cells have co-opted. In this study, we utilize a genetically tractable model for stem cell survival in the Drosophila gonad to screen drug candidates and probe chemical-genetic interactions. Our study employs three levels of small molecule screening: (1) a medium-throughput primary screen in male germline stem cells (GSCs), (2) a secondary screen with irradiation and protein-constrained food in female GSCs, and (3) a tertiary screen in breast cancer organoids in vitro. Herein, we uncover a series of small molecule drug candidates that may sensitize cancer stem cells to apoptosis. Further, we have assessed these small molecules for chemical-genetic interactions in the germline and identified the NF-κB pathway as an essential and druggable pathway in GSC quiescence and viability. Our study demonstrates the power of the Drosophila stem cell niche as a model system for targeted drug discovery.


Assuntos
Apoptose/genética , Drosophila melanogaster/genética , Testes Genéticos , Células Germinativas/metabolismo , Preparações Farmacêuticas/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Células-Tronco/metabolismo , Animais , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Drosophila melanogaster/efeitos dos fármacos , Feminino , Células Germinativas/efeitos dos fármacos , Humanos , Células MCF-7 , Masculino , Organoides/efeitos dos fármacos , Organoides/patologia , Ovário/citologia , Ovário/efeitos dos fármacos , Interferência de RNA , Células-Tronco/efeitos dos fármacos , Testículo/citologia , Testículo/efeitos dos fármacos
11.
Pharmacy (Basel) ; 9(3)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34449698

RESUMO

Oncology clinical pharmacists are uniquely positioned to make interventions to impact the knowledge, attitudes, and practices of clinicians as well as patient activation and engagement. To accomplish this goal, pharmacists can target health system-related, provider-related, and patient-related factors to enhance patient-centered care and drive behavioral health changes. Interventions that pharmacists must tackle include educating team members and patients on the medication acquisition process, communicating urgency of treatment, optimizing workflows, facilitating guideline recommendations, preventing, and managing treatment toxicities, and promoting patient self-advocacy through education and shared decision-making. As crucial members of the healthcare team, oncology pharmacists can simplify highly complex treatment regimens to facilitate and optimize patients' ownership of their care. This narrative review will focus on the example of venetoclax treatment in acute myeloid leukemia to demonstrate the impact that pharmacists provide that leads to behavioral change of patients and clinicians.

12.
Front Neuroanat ; 15: 629244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093139

RESUMO

Manipulation of the phosphatase and tensin homolog (PTEN) pathway has been suggested as a therapeutic approach to treat or prevent vision loss due to retinal disease. In this study, we investigated the effects of deleting one copy of Pten in a well-characterized class of retinal ganglion cells called α-ganglion cells in the mouse retina. In Pten +/- retinas, α-ganglion cells did not exhibit major changes in their dendritic structure, although most cells developed a few, unusual loop-forming dendrites. By contrast, α-ganglion cells exhibited a significant decrease in heterologous and homologous gap junction mediated cell coupling with other retinal ganglion and amacrine cells. Additionally, the majority of OFF α-ganglion cells (12/18 cells) formed novel coupling to displaced amacrine cells. The number of connexin36 puncta, the predominant connexin that mediates gap junction communication at electrical synapses, was decreased by at least 50% on OFF α-ganglion cells. Reduced and incorrect gap junction connectivity of α-ganglion cells will affect their functional properties and alter visual image processing in the retina. The anomalous connectivity of retinal ganglion cells would potentially limit future therapeutic approaches involving manipulation of the Pten pathway for treating ganglion cell degeneration in diseases like glaucoma, traumatic brain injury, Parkinson's, and Alzheimer's diseases.

13.
J Am Heart Assoc ; 9(13): e017559, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32538234

RESUMO

Direct oral anticoagulants (DOACs) have quickly become attractive alternatives to the long-standing standard of care in anticoagulation, vitamin K antagonist. DOACs are indicated for prevention and treatment of several cardiovascular conditions. Since the first approval in 2010, DOACs have emerged as leading therapeutic alternatives that provide both clinicians and patients with more effective, safe, and convenient treatment options in thromboembolic settings. With the expanding role of DOACs, clinicians are faced with increasingly complex decisions relating to appropriate agent, duration of treatment, and use in special populations. This review will provide an overview of DOACs and act as a practical reference for clinicians to optimize DOAC use among common challenging scenarios. Topics addressed include (1) appropriate indications; (2) use in patients with specific comorbidities; (3) monitoring parameters; (4) transitioning between anticoagulant regimens; (5) major drug interactions; and (6) cost considerations.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Inibidores do Fator Xa/uso terapêutico , Administração Oral , Tomada de Decisão Clínica , Comorbidade , Análise Custo-Benefício , Custos de Medicamentos , Interações Medicamentosas , Monitoramento de Medicamentos , Substituição de Medicamentos , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/economia , Inibidores do Fator Xa/farmacocinética , Hemorragia/induzido quimicamente , Humanos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
14.
Front Neurol ; 6: 11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25699012

RESUMO

OBJECTIVE: To determine whether topical menthol 6% gel will relieve a migraine attack. MATERIALS AND METHODS: A single-center, open-label pilot trial of 25 patients with at least 1 year of diagnosed episodic migraine and <15 headache days per month. Patients treated one migraine attack with STOPAIN topical menthol 6% gel to skull base within 2 h of headache onset. Headache pain severity was assessed prior to and after gel application. RESULTS: Thirty-two patients enrolled and 25 completed the study. Prior to treatment, 7 patients had mild pain, 13 moderate pain, and 5 severe pain. Two hours following gel application, 7 (28%) patients had no pain, 7 (28%) mild pain, 6 (25%) moderate pain, and 5 (20%) severe pain. The majority of patients had similar pain intensity (8; 32%) or improvement (13; 52%). At 24-h, only two non-rescued patients still had mild headache. Of the 25 completers, 2 patients took rescue medication prior to the 2-h period, and an additional 10 patients rescued between 2 and 24 h. CONCLUSION: Study results showed a significant improvement in headache intensity by 2 h after gel application. This pilot study shows STOPAIN gel may be effective in treating an acute migraine attack.

15.
Biol Psychiatry ; 76(7): 517-26, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24629537

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (TMS) of the dorsolateral prefrontal cortex (DLPFC) is an established treatment for depression, but its underlying mechanism of action remains unknown. Abnormalities in two large-scale neuronal networks-the frontoparietal central executive network (CEN) and the medial prefrontal-medial parietal default mode network (DMN)-are consistent findings in depression and potential therapeutic targets for TMS. Here, we assessed the impact of TMS on activity in these networks and their relation to treatment response. METHODS: We used resting state functional magnetic resonance imaging to measure functional connectivity within and between the DMN and CEN in 17 depressed patients, before and after a 5-week course of TMS. Motivated by prior reports, we focused on connectivity seeded from the DLPFC and the subgenual cingulate, a key region closely aligned with the DMN in depression. Connectivity was also compared with a cohort of 35 healthy control subjects. RESULTS: Before treatment, functional connectivity in depressed patients was abnormally elevated within the DMN and diminished within the CEN, and connectivity between these two networks was altered. Transcranial magnetic stimulation normalized depression-related subgenual hyperconnectivity in the DMN but did not alter connectivity in the CEN. Transcranial magnetic stimulation also induced anticorrelated connectivity between the DLPFC and medial prefrontal DMN nodes. Baseline subgenual connectivity predicted subsequent clinical improvement. CONCLUSIONS: Transcranial magnetic stimulation selectively modulates functional connectivity both within and between the CEN and DMN, and modulation of subgenual cingulate connectivity may play an important mechanistic role in alleviating depression. The results also highlight potential neuroimaging biomarkers for predicting treatment response.


Assuntos
Encéfalo/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/terapia , Rede Nervosa/fisiopatologia , Estimulação Magnética Transcraniana , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
16.
Proc Natl Acad Sci U S A ; 110(49): 19944-9, 2013 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-24248372

RESUMO

Information processing during human cognitive and emotional operations is thought to involve the dynamic interplay of several large-scale neural networks, including the fronto-parietal central executive network (CEN), cingulo-opercular salience network (SN), and the medial prefrontal-medial parietal default mode networks (DMN). It has been theorized that there is a causal neural mechanism by which the CEN/SN negatively regulate the DMN. Support for this idea has come from correlational neuroimaging studies; however, direct evidence for this neural mechanism is lacking. Here we undertook a direct test of this mechanism by combining transcranial magnetic stimulation (TMS) with functional MRI to causally excite or inhibit TMS-accessible prefrontal nodes within the CEN or SN and determine consequent effects on the DMN. Single-pulse excitatory stimulations delivered to only the CEN node induced negative DMN connectivity with the CEN and SN, consistent with the CEN/SN's hypothesized negative regulation of the DMN. Conversely, low-frequency inhibitory repetitive TMS to the CEN node resulted in a shift of DMN signal from its normally low-frequency range to a higher frequency, suggesting disinhibition of DMN activity. Moreover, the CEN node exhibited this causal regulatory relationship primarily with the medial prefrontal portion of the DMN. These findings significantly advance our understanding of the causal mechanisms by which major brain networks normally coordinate information processing. Given that poorly regulated information processing is a hallmark of most neuropsychiatric disorders, these findings provide a foundation for ways to study network dysregulation and develop brain stimulation treatments for these disorders.


Assuntos
Função Executiva/fisiologia , Lobo Frontal/fisiologia , Processos Mentais/fisiologia , Rede Nervosa/fisiologia , Lobo Parietal/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Magnética Transcraniana
17.
Neuropsychopharmacology ; 38(10): 1889-98, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23673864

RESUMO

Anxiety disorders are a diverse group of clinical states. Post-traumatic stress disorder (PTSD) and generalized anxiety disorder (GAD), eg, share elevated anxiety symptoms, but differ with respect to fear-related memory dysregulation. As the hippocampus is implicated in both general anxiety and fear memory, it may be an important brain locus for mapping the similarities and differences among anxiety disorders. Anxiety and fear also functionally associate with different subdivisions of the hippocampus along its longitudinal axis: the human posterior (rodent dorsal) hippocampus is involved in memory, through connectivity with the medial prefrontal-medial parietal default-mode network, whereas the anterior (rodent ventral) hippocampus is involved in anxiety, through connectivity with limbic-prefrontal circuits. We examined whether differential hippocampal network functioning may help account for similarities and differences in symptoms in PTSD and GAD. Network-sensitive functional magnetic resonance imaging-based resting-state intrinsic connectivity methods, along with task-based assessment of posterior hippocampal/default-mode network function, were used. As predicted, in healthy subjects resting-state connectivity dissociated between posterior hippocampal connectivity with the default-mode network, and anterior hippocampal connectivity to limbic-prefrontal circuitry. The posterior hippocampus and the associated default-mode network, across both resting-state connectivity and task-based measures, were perturbed in PTSD relative to each of the other groups. By contrast, we found only modest support for similarly blunted anterior hippocampal connectivity across both patient groups. These findings provide new insights into the neural circuit-level dysfunctions that account for similar vs different features of two major anxiety disorders, through a translational framework built on animal work and carefully selected clinical disorders.


Assuntos
Transtornos de Ansiedade/fisiopatologia , Hipocampo/fisiopatologia , Sistema Límbico/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Vias Neurais/fisiopatologia , Desempenho Psicomotor/fisiologia
18.
J Psychiatr Res ; 45(4): 526-38, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20797730

RESUMO

Persons with schizophrenia often appraise other individuals as threatening or persecutory. To evaluate social appraisal in schizophrenia, we probed brain networks with a task in which subjects judged whether or not they liked face stimuli with emotional expressions. We predicted that appraising negative expressions would engage patients, more than controls, and negative faces would be related to higher levels of negative affect and produce increased activity in the medial frontal cortex, an area involved in social appraisal. Twenty-one stable outpatients with chronic non-affective psychosis (16 schizophrenic, 5 schizoaffective) and 21 healthy subjects underwent functional magnetic resonance imaging. Compared with the control subjects, patients were slower to respond, but particularly slow when they judged negatively-valenced faces, a slowness correlated with negative affect in the psychosis patients. Appraisal activated the medial prefrontal cortex (mPFC) across all face valences. For negative expressions, patients exhibited greater activation of the dorsal anterior cingulate cortex (dACC). A psychophysiological interaction analysis of the dACC revealed co-modulation of the mPFC in controls, significantly less in patients, and a trend for co-modulation of occipital cortex in the patients. Activity in occipital cortex correlated with poor social adjustment and impaired social cognition, and co-modulation of the occipital gyrus by the dACC was correlated with poorer social cognition. The findings link appraisal of negative affect with aberrant activation of the medial frontal cortex, while early sensory processing of this social cognitive task was linked with poor social function, reflecting either top-down or bottom-up influences.


Assuntos
Lobo Frontal/fisiopatologia , Transtornos Mentais/patologia , Transtornos Mentais/psicologia , Lobo Occipital/fisiopatologia , Apoio Social , Adulto , Análise de Variância , Mapeamento Encefálico , Doença Crônica , Transtornos Cognitivos/etiologia , Face , Feminino , Lobo Frontal/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Rede Nervosa/irrigação sanguínea , Rede Nervosa/fisiopatologia , Testes Neuropsicológicos , Lobo Occipital/irrigação sanguínea , Oxigênio/sangue , Estimulação Luminosa/métodos
19.
Neuroimage ; 51(2): 930-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20188190

RESUMO

Human communication and survival depend on effective social information processing. Abundant behavioral evidence has shown that humans efficiently judge preferences for other individuals, a critical task in social interaction, yet the neural mechanism of this basic social evaluation, remains less than clear. Using a socio-emotional preference task and connectivity analyses (psycho-physiological interaction) of fMRI data, we first demonstrated that cortical midline structures (medial prefrontal and posterior cingulate cortices) and the task-positive network typically implicated in carrying out goal-directed tasks (pre-supplementary motor area, dorsal anterior cingulate and bilateral frontoparietal cortices) were both recruited when subjects made a preference judgment, relative to gender identification, to human faces. Connectivity analyses further showed network interactions among these cortical midline structures, and with the task-positive network, both of which vary as a function of social preference. Overall, the data demonstrate the involvement of cortical midline structures in forming social preference, and provide evidence of network interactions which might reflect a mechanism by which an individual regularly forms and expresses this fundamental decision.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Emoções/fisiologia , Vias Neurais/fisiologia , Comportamento Social , Adulto , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Schizophr Bull ; 36(4): 713-22, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18990709

RESUMO

The thalamus plays a central and dynamic role in information transmission and processing in the brain. Multiple studies reveal increasing association between schizophrenia and dysfunction of the thalamus, in particular the medial dorsal nucleus (MDN), and its projection targets. The medial dorsal thalamic connections to the prefrontal cortex are of particular interest, and explicit in vivo evidence of this connection in healthy humans is sparse. Additionally, recent neuroimaging evidence has demonstrated disconnection among a variety of cortical regions in schizophrenia, though the MDN thalamic prefrontal cortex network has not been extensively probed in schizophrenia. To this end, we have examined thalamo-anterior cingulate cortex connectivity using detection of low-frequency blood oxygen level dependence fluctuations (LFBF) during a resting-state paradigm. Eleven schizophrenic patients and 12 healthy control participants were enrolled in a study of brain thalamocortical connectivity. Resting-state data were collected, and seed-based connectivity analysis was performed to identify the thalamocortical network. First, we have shown there is MDN thalamocortical connectivity in healthy controls, thus demonstrating that LFBF analysis is a manner to probe the thalamocortical network. Additionally, we have found there is statistically significantly reduced thalamocortical connectivity in schizophrenics compared with matched healthy controls. We did not observe any significant difference in motor networks between groups. We have shown that the thalamocortical network is observable using resting-state connectivity in healthy controls and that this network is altered in schizophrenia. These data support a disruption model of the thalamocortical network and are consistent with a disconnection hypothesis of schizophrenia.


Assuntos
Córtex Cerebral/fisiopatologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Rede Nervosa/fisiopatologia , Consumo de Oxigênio/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Tálamo/fisiopatologia , Adulto , Mapeamento Encefálico , Dominância Cerebral/fisiologia , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/psicologia , Valores de Referência , Esquizofrenia/diagnóstico
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