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1.
J Neurosci ; 44(14)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38388424

RESUMO

A missense mutation in the transcription repressor Nucleus accumbens-associated 1 (NACC1) gene at c.892C>T (p.Arg298Trp) on chromosome 19 causes severe neurodevelopmental delay ( Schoch et al., 2017). To model this disorder, we engineered the first mouse model with the homologous mutation (Nacc1+/R284W ) and examined mice from E17.5 to 8 months. Both genders had delayed weight gain, epileptiform discharges and altered power spectral distribution in cortical electroencephalogram, behavioral seizures, and marked hindlimb clasping; females displayed thigmotaxis in an open field. In the cortex, NACC1 long isoform, which harbors the mutation, increased from 3 to 6 months, whereas the short isoform, which is not present in humans and lacks aaR284 in mice, rose steadily from postnatal day (P) 7. Nuclear NACC1 immunoreactivity increased in cortical pyramidal neurons and parvalbumin containing interneurons but not in nuclei of astrocytes or oligodendroglia. Glial fibrillary acidic protein staining in astrocytic processes was diminished. RNA-seq of P14 mutant mice cortex revealed over 1,000 differentially expressed genes (DEGs). Glial transcripts were downregulated and synaptic genes upregulated. Top gene ontology terms from upregulated DEGs relate to postsynapse and ion channel function, while downregulated DEGs enriched for terms relating to metabolic function, mitochondria, and ribosomes. Levels of synaptic proteins were changed, but number and length of synaptic contacts were unaltered at 3 months. Homozygosity worsened some phenotypes including postnatal survival, weight gain delay, and increase in nuclear NACC1. This mouse model simulates a rare form of autism and will be indispensable for assessing pathophysiology and targets for therapeutic intervention.


Assuntos
Transtorno Autístico , Fatores de Transcrição , Animais , Feminino , Humanos , Masculino , Camundongos , Mutação/genética , Proteínas de Neoplasias/genética , Isoformas de Proteínas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Aumento de Peso
2.
J Geriatr Psychiatry Neurol ; 36(2): 143-154, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35603772

RESUMO

Introduction: Parkinson's disease (PD) is characterized by high-rates of depression with limited evidence-based treatment options to improve mood. Objective: To expand therapeutic options, we evaluated the feasibility and effect of a telehealth mindfulness-based cognitive therapy intervention adapted for PD (MBCT-PD) in a sample of participants with DSM-5 depressive disorders. Methods: Fifteen participants with PD and clinically-significant depression completed 9 sessions of MBCT-PD. Depression, anxiety, and quality of life were evaluated at baseline, endpoint, and 1-month follow-up. Results: Telehealth MBCT-PD was feasible and beneficial. Completion rates exceeded 85% and treatment satisfaction rates were high. Notable improvements were observed for depression, anxiety, and quality of life over the course of the trial. Conclusion: Telehealth MBCT-PD shows promise and warrants further evaluation via randomized clinical trial with more diverse participants. Such research holds the potential to expand the range of therapeutic options for depression in PD, thereby setting the stage for personalized care.


Assuntos
Terapia Cognitivo-Comportamental , Atenção Plena , Doença de Parkinson , Telemedicina , Humanos , Projetos Piloto , Depressão/terapia , Depressão/psicologia , Qualidade de Vida/psicologia , Doença de Parkinson/complicações , Doença de Parkinson/terapia , Resultado do Tratamento
3.
Nucleic Acids Res ; 49(21): 12069-12088, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34850120

RESUMO

Oligonucleotides is an emerging class of chemically-distinct therapeutic modalities, where extensive chemical modifications are fundamental for their clinical applications. Inter-nucleotide backbones are critical to the behaviour of therapeutic oligonucleotides, but clinically explored backbone analogues are, effectively, limited to phosphorothioates. Here, we describe the synthesis and bio-functional characterization of an internucleotide (E)-vinylphosphonate (iE-VP) backbone, where bridging oxygen is substituted with carbon in a locked stereo-conformation. After optimizing synthetic pathways for iE-VP-linked dimer phosphoramidites in different sugar contexts, we systematically evaluated the impact of the iE-VP backbone on oligonucleotide interactions with a variety of cellular proteins. Furthermore, we systematically evaluated the impact of iE-VP on RNA-Induced Silencing Complex (RISC) activity, where backbone stereo-constraining has profound position-specific effects. Using Huntingtin (HTT) gene causative of Huntington's disease as an example, iE-VP at position 6 significantly enhanced the single mismatch discrimination ability of the RISC without negative impact on silencing of targeting wild type htt gene. These findings suggest that the iE-VP backbone can be used to modulate the activity and specificity of RISC. Our study provides (i) a new chemical tool to alter oligonucleotide-enzyme interactions and metabolic stability, (ii) insight into RISC dynamics and (iii) a new strategy for highly selective SNP-discriminating siRNAs.


Assuntos
Doença de Huntington/genética , Oligonucleotídeos/metabolismo , RNA Interferente Pequeno/metabolismo , Alelos , Humanos , Organofosfonatos
4.
Behav Brain Sci ; 46: e61, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37154351

RESUMO

The fearful ape hypothesis proposes that heightened fearfulness in humans is adaptive. However, despite its attractive anthropocentric narrative, the evidence presented for greater fearfulness in humans versus other apes is not sufficient to support this claim. Conceptualization, context, and comparison are strongly lacking in Grossmann's proposal, but are key to understanding variation in the fear response among individuals and species.


Assuntos
Formação de Conceito , Medo , Humanos , Medo/fisiologia
5.
Zoo Biol ; 41(4): 281-291, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35037289

RESUMO

Animal cognition covers various mental processes including perception, learning, decision-making and memory, and animal behavior is often used as a proxy for measuring cognition. Animal cognition/behavior research has multiple benefits; it provides fundamental knowledge of animal biology and evolution but can also have applied conservation and welfare applications. Zoos provide an excellent yet relatively untapped resource for animal cognition research, because they house a wide variety of species-many of which are under threat-and allow close observation and relatively high experimental control compared to the wild. Multi-zoo collaboration leads to increased sample size and species representation, which in turn leads to more robust science. However, there are salient challenges associated with zoo-based cognitive research, which are animal-based (e.g., small sample sizes at single zoos, untrained/unhabituated subjects, side effects) and human-based (e.g., time restrictions, safety concerns, and perceptions of animals interacting with unnatural technology or apparatus). We aim to increase the understanding and subsequent uptake of animal cognition research in zoos, by transparently outlining the main benefits and challenges. Importantly, we use our own research (1) a study on novelty responses in hornbills, and (2) a multi-site collaboration called the "ManyBirds" Project to demonstrate how challenges may be overcome. These potential options include using "drop and go" apparatuses that require no training, close human contact or animal separation. This study is aimed at zoo animal care and research staff, as well as external researchers interested in zoo-based studies.


Assuntos
Bem-Estar do Animal , Animais de Zoológico , Criação de Animais Domésticos , Animais , Animais de Zoológico/fisiologia , Comportamento Animal/fisiologia , Cognição , Humanos
6.
Mov Disord ; 36(11): 2549-2558, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33710659

RESUMO

BACKGROUND: For several decades, a myriad of factors have contributed to the inadequate diagnosis and management of depression in Parkinson's disease (PD), leaving up to 60% of significantly symptomatic patients untreated. Poor access to evidence-based neuropsychiatric care is one major barrier to achieving optimal Parkinson's outcomes. OBJECTIVE: The goal of this study was to compare the efficacy of individual Parkinson's-informed, video-to-home cognitive-behavioral therapy (experimental group), to clinic-based treatment as usual (control group), for depression in PD. METHOD: Ninety United States military veterans with clinical diagnoses of both depression and PD were computer-randomized (1:1) to either the experimental or control group; randomization was stratified by baseline antidepressant use and blind to all other baseline data. The acute treatment period spanned 10 weeks and was followed by a 6-month extension phase. The Hamilton Depression Rating Scale was the a priori primary outcome. Depression treatment response was defined as a score ≤2 on the Clinical Global Impression Improvement Scale. All statistical analyses were intent to treat. RESULTS: Video-to-home cognitive-behavioral therapy outperformed clinic-based treatment as usual across three separate depression measures (P < 0.001). Effects were observed at the end of acute treatment and maintained through 6-month follow-up. Number needed to treat (based on treatment response classification) was 2.5 with an absolute risk reduction of 40%. CONCLUSION: Video-to-home cognitive-behavioral therapy may be an effective intervention to bypass access barriers to specialized, evidence-based depression care in PD and to address the unmet neuropsychiatric treatment needs of the Parkinson's community. © 2021 International Parkinson and Movement Disorder Society.


Assuntos
Terapia Cognitivo-Comportamental , Doença de Parkinson , Telemedicina , Depressão/terapia , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Resultado do Tratamento
7.
Eur J Vasc Endovasc Surg ; 61(3): 491-501, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33388237

RESUMO

OBJECTIVE: Most major lower limb amputations are related to peripheral artery disease (PAD) or diabetes. Just 40% of patients who undergo major lower limb amputation will use a prosthesis yet measures of surgical success commonly focus on prosthesis use. Patient reported outcome measures (PROMs) are valuable to comprehensively evaluate health related quality of life (HRQL) after surgery. This systematic review aimed to identify and describe PROMs available to assess HRQL in patients after amputation for PAD or diabetes. METHODS: A search was conducted based on the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) for systematic reviews of PROMs. Ovid MEDLINE, Ovid EMBASE, PsycINFO, CINAHL, and Cochrane CENTRAL were also searched from inception until August 2019. Included were articles describing the development, measurement properties, or evaluation of HRQL via a PROM in adult patients after amputation for PAD or diabetes. Studies of amputation exclusively for trauma or malignancy were excluded. Data were collected on study characteristics, PROM characteristics (generic/disease specific), and properties of amputation specific PROMs. RESULTS: Of 3 317 abstracts screened, 111 full text articles were assessed for eligibility and 64 included. Fifty-six studies evaluated HRQL, with 23 (46%) of these using an amputation specific PROM to do so. Eleven different amputation specific PROMs were identified, 10 (91%) of which were developed only for prosthesis users. One measure was suitable for use in all patients after amputation. This "Amputee single item mobility measure" includes a single item evaluating mobility. Nine studies reported some psychometric testing of an amputation specific PROM. CONCLUSION: A well tested, multidimensional PROM applicable to wheelchair and prosthetic users after amputation is lacking and urgently needed for studies in this field. Future work to develop an appropriate measure is required.


Assuntos
Amputação Cirúrgica , Amputados , Angiopatias Diabéticas/cirurgia , Extremidade Inferior/irrigação sanguínea , Medidas de Resultados Relatados pelo Paciente , Doença Arterial Periférica/cirurgia , Qualidade de Vida , Amputação Cirúrgica/efeitos adversos , Membros Artificiais , Deambulação com Auxílio , Angiopatias Diabéticas/diagnóstico , Angiopatias Diabéticas/fisiopatologia , Nível de Saúde , Humanos , Limitação da Mobilidade , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Ajuste de Prótese , Resultado do Tratamento , Cadeiras de Rodas
8.
Anim Cogn ; 23(1): 71-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630344

RESUMO

Self-control underlies cognitive abilities such as decision making and future planning. Delay of gratification is a measure of self-control and involves obtaining a more valuable outcome in the future by tolerating a delay or investing a greater effort in the present. Contextual issues, such as reward visibility and type, may influence delayed gratification performance, although there has been limited comparative investigation between humans and other animals, particularly non-primate species. Here, we adapted an automated 'rotating tray' paradigm used previously with capuchin monkeys to test for delay of gratification ability that requires little pre-test training, where the subject must forgo an immediate, less preferred reward for a delayed, more preferred one. We tested New Caledonian crows and 3-5-year-old human children. We manipulated reward types to differ in quality or quantity (Experiments 1 and 2) as well as visibility (Experiment 2). In Experiments 1 and 2, both species performed better when the rewards varied in quality as opposed to quantity, though performed above chance in both conditions. In Experiment 1, both crows and children were able to delay gratification when both rewards were visible. In Experiment 2, 5-year-old children outperformed 3- and 4-year olds, though overall children still performed well, while the crows struggled when reward visibility was manipulated, a result which may relate to difficulties in tracking the experimenters' hands during baiting. We discuss these findings in relation to the role of contextual issues on self-control when making species comparisons and investigating the mechanisms of self-control.


Assuntos
Corvos , Desvalorização pelo Atraso , Autocontrole , Animais , Cebus , Humanos , Recompensa
9.
Proc Biol Sci ; 286(1894): 20182332, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30963864

RESUMO

Humans use a variety of cues to infer an object's weight, including how easily objects can be moved. For example, if we observe an object being blown down the street by the wind, we can infer that it is light. Here, we tested whether New Caledonian crows make this type of inference. After training that only one type of object (either light or heavy) was rewarded when dropped into a food dispenser, birds observed pairs of novel objects (one light and one heavy) suspended from strings in front of an electric fan. The fan was either on-creating a breeze which buffeted the light, but not the heavy, object-or off, leaving both objects stationary. In subsequent test trials, birds could drop one, or both, of the novel objects into the food dispenser. Despite having no opportunity to handle these objects prior to testing, birds touched the correct object (light or heavy) first in 73% of experimental trials, and were at chance in control trials. Our results suggest that birds used pre-existing knowledge about the behaviour exhibited by differently weighted objects in the wind to infer their weight, using this information to guide their choices.


Assuntos
Corvos/fisiologia , Aprendizagem por Discriminação , Animais , Feminino , Masculino
10.
Mol Ther ; 26(6): 1520-1528, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29699940

RESUMO

Small extracellular vesicles (sEVs) show promise as natural nano-devices for delivery of therapeutic RNA, but efficient loading of therapeutic RNA remains a challenge. We have recently shown that the attachment of cholesterol to small interfering RNAs (siRNAs) enables efficient and productive loading into sEVs. Here, we systematically explore the ability of lipid conjugates-fatty acids, sterols, and vitamins-to load siRNAs into sEVs and support gene silencing in primary neurons. Hydrophobicity of the conjugated siRNAs defined loading efficiency and the silencing activity of siRNA-sEVs complexes. Vitamin-E-conjugated siRNA supported the best loading into sEVs and productive RNA delivery to neurons.


Assuntos
Vesículas Extracelulares/química , Lipídeos/química , RNA Interferente Pequeno/química , Células Cultivadas , Inativação Gênica/fisiologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Interferência de RNA
11.
Mol Ther ; 26(8): 1973-1982, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29937418

RESUMO

Extracellular vesicles are promising delivery vesicles for therapeutic RNAs. Small interfering RNA (siRNA) conjugation to cholesterol enables efficient and reproducible loading of extracellular vesicles with the therapeutic cargo. siRNAs are typically chemically modified to fit an application. However, siRNA chemical modification pattern has not been specifically optimized for extracellular vesicle-mediated delivery. Here we used cholesterol-conjugated, hydrophobically modified asymmetric siRNAs (hsiRNAs) to evaluate the effect of backbone, 5'-phosphate, and linker chemical modifications on productive hsiRNA loading onto extracellular vesicles. hsiRNAs with a combination of 5'-(E)-vinylphosphonate and alternating 2'-fluoro and 2'-O-methyl backbone modifications outperformed previously used partially modified siRNAs in extracellular vesicle-mediated Huntingtin silencing in neurons. Between two commercially available linkers (triethyl glycol [TEG] and 2-aminobutyl-1-3-propanediol [C7]) widely used to attach cholesterol to siRNAs, TEG is preferred compared to C7 for productive exosomal loading. Destabilization of the linker completely abolished silencing activity of loaded extracellular vesicles. The loading of cholesterol-conjugated siRNAs was saturated at ∼3,000 siRNA copies per extracellular vesicle. Overloading impaired the silencing activity of extracellular vesicles. The data reported here provide an optimization scheme for the successful use of hydrophobic modification as a strategy for productive loading of RNA cargo onto extracellular vesicles.


Assuntos
Colesterol/química , Vesículas Extracelulares/química , Proteína Huntingtina/genética , RNA Interferente Pequeno/química , Animais , Células Cultivadas , Humanos , Camundongos , Mutação , Propilenoglicóis/química
12.
Mol Ther ; 26(12): 2838-2847, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30341012

RESUMO

Exosomes can deliver therapeutic RNAs to neurons. The composition and the safety profile of exosomes depend on the type of the exosome-producing cell. Mesenchymal stem cells are considered to be an attractive cell type for therapeutic exosome production. However, scalable methods to isolate and manufacture exosomes from mesenchymal stem cells are lacking, a limitation to the clinical translation of exosome technology. We evaluate mesenchymal stem cells from different sources and find that umbilical cord-derived mesenchymal stem cells produce the highest exosome yield. To optimize exosome production, we cultivate umbilical cord-derived mesenchymal stem cells in scalable microcarrier-based three-dimensional (3D) cultures. In combination with the conventional differential ultracentrifugation, 3D culture yields 20-fold more exosomes (3D-UC-exosomes) than two-dimensional cultures (2D-UC-exosomes). Tangential flow filtration (TFF) in combination with 3D mesenchymal stem cell cultures further improves the yield of exosomes (3D-TFF-exosomes) 7-fold over 3D-UC-exosomes. 3D-TFF-exosomes are seven times more potent in small interfering RNA (siRNA) transfer to neurons compared with 2D-UC-exosomes. Microcarrier-based 3D culture and TFF allow scalable production of biologically active exosomes from mesenchymal stem cells. These findings lift a major roadblock for the clinical utility of mesenchymal stem cell exosomes.


Assuntos
Exossomos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Feminino , Inativação Gênica , Células-Tronco Mesenquimais/citologia , Camundongos , Neurônios/metabolismo , Proteoma , RNA Interferente Pequeno/genética , Esferoides Celulares , Cordão Umbilical/citologia
13.
J Am Pharm Assoc (2003) ; 58(6): 652-658, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30170967

RESUMO

OBJECTIVE: The purpose of this study was to design, pilot, and evaluate a community "tech-check-tech" (TCT) program as a strategy for pharmacy practice advancement. SETTING: Community pharmacy with both mail order and outpatient pharmacy services. PRACTICE DESCRIPTION: The policies, technician training requirements, prescription eligibility requirements, and quality assurance measures necessary for the pilot were developed. The TCT workflows and procedures were integrated into the existing prescription dispensing framework at a pilot site. An analysis of pharmacist and technician checking accuracy was conducted with a 4-week data collection period for each role. To determine TCT technician accuracy, the TCT technician performed the first product verification check after the prescription was filled by a pharmacy staff member. If the TCT technician found an error, they documented the error and returned the prescription to the filling technician for correction. If the prescription was filled correctly, the TCT technician passed the prescription to a pharmacist for final verification. The pharmacist documented any incorrect prescriptions that the TCT technician verified. Pharmacist accuracy was measured through direct pharmacist observation. Direct observation was also used to measure and record pharmacist and technician prescription checking time. The data were then used to evaluate pharmacist time savings as a result of community TCT, while ensuring prescription dispensing accuracy. PRACTICE INNOVATION: TCT was piloted in a community pharmacy. EVALUATION: An analysis of pharmacist and technician checking accuracy was conducted with a 4-week data collection period for each role. To determine TCT technician accuracy, the TCT technician performed the first product verification check after the prescription was filled by pharmacy staff. If the TCT technician found an error, they documented the error and returned the prescription to the filling technician for correction. If filled correctly, the TCT technician passed the prescription to a pharmacist for final verification. The pharmacist documented any incorrect prescriptions that the TCT technician verified. Pharmacist accuracy was measured through direct pharmacist observation. Direct observation was also used to measure and record pharmacist and technician prescription checking time. This data was then used to evaluate pharmacist time savings as a result of community TCT, while ensuring prescription dispensing accuracy. RESULTS: A TCT workflow was piloted successfully in the community pharmacy setting. Technicians were at least as accurate as pharmacists, as validated with statistical analysis (99.95% [95% CI 99.89%-99.99%] versus 99.74% [95% CI 99.61%-99.87%]), and patient safety was maintained. Time studies allowed for the quantification of potential pharmacist time savings (23 days per year) resulting from the implementation of a community TCT program. CONCLUSION: This study demonstrates the feasibility of a TCT program in the community pharmacy setting.


Assuntos
Serviços Comunitários de Farmácia/normas , Técnicos em Farmácia/normas , Humanos , Erros de Medicação/prevenção & controle , Pacientes Ambulatoriais , Farmácias/normas , Farmacêuticos/normas , Farmácia/normas , Prescrições/normas , Papel Profissional , Fluxo de Trabalho
14.
Epilepsy Behav ; 58: 127-32, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27074299

RESUMO

BACKGROUND: Prior studies have shown that switching patients from inducing antiepileptic drugs (AEDs) to lamotrigine, levetiracetam, or topiramate reduces serum lipids and C-reactive protein (CRP). These studies were all of short duration, and some drugs, such as zonisamide, have not been investigated. METHODS: We recruited 41 patients taking phenytoin or carbamazepine who were being switched to zonisamide, lamotrigine, or levetiracetam. We measured serum lipids and CRP before the switch, >6weeks after, and >6months after. An untreated control group (n=14) underwent similar measurement. We combined these data with those of our previous investigation (n=34 patients and 16 controls) of a very similar design. RESULTS: There were no differences in outcome measures between the two inducing AEDs nor among the three noninducing AEDs. Total cholesterol (TC), atherogenic lipids, and CRP were higher under inducer treatment than in controls. All measures were elevated under inducer treatment relative to noninducer treatment, including TC (24mg/dL higher, 95% CI: 17.5-29.9, p<0.001) and CRP (72% higher, 95% CI: 41%-111%, p<0.001). The difference between drug treatments was clinically meaningful for atherogenic lipids (16%, 95% CI: 11%-20%, p<0.001) but small for high-density lipoprotein cholesterol (5%, 95% CI: 1%-9%, p<0.05). All measures were stable between 6weeks and 6months after drug switch. CONCLUSIONS: We demonstrate that switching from inducing to noninducing AEDs produces an enduring reduction in serum lipids and CRP. These results provide further evidence that inducing AEDs may be associated with elevated vascular disease risk. These are the first vascular risk marker data in patients taking zonisamide, which shows a profile similar to that of other noninducing AEDs.


Assuntos
Anticonvulsivantes/administração & dosagem , Proteína C-Reativa/metabolismo , Substituição de Medicamentos/métodos , Epilepsias Parciais/sangue , Epilepsias Parciais/tratamento farmacológico , Lipídeos/sangue , Biomarcadores/sangue , Proteína C-Reativa/antagonistas & inibidores , Carbamazepina/administração & dosagem , Quimioterapia Combinada , Feminino , Frutose/administração & dosagem , Frutose/análogos & derivados , Humanos , Isoxazóis/administração & dosagem , Lamotrigina , Levetiracetam , Lipídeos/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Fenitoína/administração & dosagem , Piracetam/administração & dosagem , Piracetam/análogos & derivados , Fatores de Tempo , Topiramato , Resultado do Tratamento , Triazinas/administração & dosagem , Zonisamida
15.
Proc Natl Acad Sci U S A ; 109(40): 16389-91, 2012 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-22988112

RESUMO

The ability to make inferences about hidden causal mechanisms underpins scientific and religious thought. It also facilitates the understanding of social interactions and the production of sophisticated tool-using behaviors. However, although animals can reason about the outcomes of accidental interventions, only humans have been shown to make inferences about hidden causal mechanisms. Here, we show that tool-making New Caledonian crows react differently to an observable event when it is caused by a hidden causal agent. Eight crows watched two series of events in which a stick moved. In the first set of events, the crows observed a human enter a hide, a stick move, and the human then leave the hide. In the second, the stick moved without a human entering or exiting the hide. The crows inspected the hide and abandoned probing with a tool for food more often after the second, unexplained series of events. This difference shows that the crows can reason about a hidden causal agent. Comparative studies with the methodology outlined here could aid in elucidating the selective pressures that led to the evolution of this cognitive ability.


Assuntos
Cognição/fisiologia , Corvos/fisiologia , Resolução de Problemas/fisiologia , Comportamento de Utilização de Ferramentas/fisiologia , Animais , Nova Caledônia
16.
Proc Biol Sci ; 281(1787)2014 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-24920476

RESUMO

Humans are capable of simply observing a correlation between cause and effect, and then producing a novel behavioural pattern in order to recreate the same outcome. However, it is unclear how the ability to create such causal interventions evolved. Here, we show that while 24-month-old children can produce an effective, novel action after observing a correlation, tool-making New Caledonian crows cannot. These results suggest that complex tool behaviours are not sufficient for the evolution of this ability, and that causal interventions can be cognitively and evolutionarily disassociated from other types of causal understanding.


Assuntos
Evolução Biológica , Cognição , Corvos/fisiologia , Aprendizagem , Comportamento de Utilização de Ferramentas , Animais , Pré-Escolar , Condicionamento Operante , Feminino , Humanos , Lactente , Masculino , Nova Caledônia
17.
bioRxiv ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38895198

RESUMO

Oligonucleotide therapeutics (ASOs and siRNAs) have been explored for modulation of gene expression in the central nervous system (CNS), with several drugs approved and many in clinical evaluation. Administration of highly concentrated oligonucleotides to the CNS can induce acute neurotoxicity. We demonstrate that delivery of concentrated oligonucleotides to the CSF in awake mice induces acute toxicity, observable within seconds of injection. Electroencephalography (EEG) and electromyography (EMG) in awake mice demonstrated seizures. Using ion chromatography, we show that siRNAs can tightly bind Ca2+ and Mg2+ up to molar equivalents of the phosphodiester (PO)/phosphorothioate (PS) bonds independently of the structure or phosphorothioate content. Optimization of the formulation by adding high concentrations (above biological levels) of divalent cations (Ca2+ alone, Mg2+ alone, or Ca2+ and Mg2+) prevents seizures with no impact on the distribution or efficacy of the oligonucleotide. The data here establishes the importance of adding Ca2+ and Mg2+ to the formulation for the safety of CNS administration of therapeutic oligonucleotides.

18.
bioRxiv ; 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38774633

RESUMO

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by CAG repeat expansion in the first exon of the huntingtin gene (HTT). Oligonucleotide therapeutics, such as short interfering RNA (siRNA), reduce levels of huntingtin mRNA and protein in vivo and are considered a viable therapeutic strategy. However, the extent to which they silence HTT mRNA in the nucleus is not established. We synthesized siRNA cross-reactive to mouse (wild-type) Htt and human (mutant) HTT in a di-valent scaffold and delivered to two mouse models of HD. In both models, di-valent siRNA sustained lowering of wild-type Htt, but not mutant HTT mRNA expression in striatum and cortex. Near-complete silencing of both mutant HTT protein and wild-type Htt protein was observed in both models. Subsequent fluorescent in situ hybridization (FISH) analysis shows that di-valent siRNA acts predominantly on cytoplasmic mutant HTT transcripts, leaving clustered mutant HTT transcripts in the nucleus largely intact in treated HD mouse brains. The observed differences between mRNA and protein levels, exaggerated in the case of extended repeats, might apply to other repeat-associated neurological disorders.

19.
Nat Commun ; 15(1): 2634, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528030

RESUMO

Real-time lab analysis is needed to support clinical decision making and research on human missions to the Moon and Mars. Powerful laboratory instruments, such as flow cytometers, are generally too cumbersome for spaceflight. Here, we show that scant test samples can be measured in microgravity, by a trained astronaut, using a miniature cytometry-based analyzer, the rHEALTH ONE, modified specifically for spaceflight. The base device addresses critical spaceflight requirements including minimal resource utilization and alignment-free optics for surviving rocket launch. To fully enable reduced gravity operation onboard the space station, we incorporated bubble-free fluidics, electromagnetic shielding, and gravity-independent sample introduction. We show microvolume flow cytometry from 10 µL sample drops, with data from five simultaneous channels using 10 µs bin intervals during each sample run, yielding an average of 72 million raw data points in approximately 2 min. We demonstrate the device measures each test sample repeatably, including correct identification of a sample that degraded in transit to the International Space Station. This approach can be utilized to further our understanding of spaceflight biology and provide immediate, actionable diagnostic information for management of astronaut health without the need for Earth-dependent analysis.


Assuntos
Voo Espacial , Ausência de Peso , Humanos , Citometria de Fluxo , Lua
20.
Cognition ; 236: 105433, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37001438

RESUMO

The ability to shift from current to future perspective is pivotal to future-oriented cognition. With two distinct cultural groups, UK (N = 92) and China (N = 90), we investigated 3 to 5-year-olds' understanding of preference changes occurring within themselves and their peers (another child). We administered a battery of representative tasks of executive function and theory of mind to examine their underlying relationships with children's ability to predict future preferences. British 3-year-olds outperformed Chinese children in predicting future preferences, while no country differences were observed between the 4- and 5-year-olds. Across the UK and China, children were more accurate when predicting for their peers than for themselves. They were also more accurate when their current preferences were identified first, i.e. before answering questions about the future. Chinese children outperformed their British counterparts on inhibition and cognitive flexibility tasks whereas there were no Eastern and Western differences in their theory of mind abilities. After controlling for age and children's knowledge of generic adult preferences, children's performance in the inhibition and cognitive flexibility tasks were significantly correlated with the prediction of their own future preferences, but they were not significantly correlated when predicting for a peer. These results are discussed in relation to the conflicts between multiple perspectives and the cognitive correlates of future-oriented cognition.


Assuntos
Cognição , População do Leste Asiático , Criança , Pré-Escolar , Humanos , Desenvolvimento Infantil/fisiologia , Função Executiva/fisiologia , Previsões
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