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1.
J Physiol ; 601(1): 25-35, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35851953

RESUMO

The thalamus and cortex are interconnected both functionally and anatomically and share a common developmental trajectory. Interactions between the mediodorsal thalamus (MD) and different parts of the prefrontal cortex are essential in cognitive processes, such as learning and adaptive decision-making. Cortico-thalamocortical interactions involving other dorsal thalamic nuclei, including the anterior thalamus and pulvinar, also influence these cognitive processes. Our work, and that of others, indicates a crucial influence of these interdependent cortico-thalamocortical neural networks that contributes actively to the processing of information within the cortex. Each of these thalamic nuclei also receives potent subcortical inputs that are likely to provide additional influences on their regulation of cortical activity. Here, we highlight our current neuroscientific research aimed at establishing when cortico-MD thalamocortical neural network communication is vital within the context of a rapid learning and memory discrimination task. We are collecting evidence of MD-prefrontal cortex neural network communication in awake, behaving male rhesus macaques. Given the prevailing evidence, further studies are needed to identify both broad and specific mechanisms that govern how the MD, anterior thalamus and pulvinar cortico-thalamocortical interactions support learning, memory and decision-making. Current evidence shows that the MD (and the anterior thalamus) are crucial for frontotemporal communication, and the pulvinar is crucial for frontoparietal communication. Such work is crucial to advance our understanding of the neuroanatomical and physiological bases of these brain functions in humans. In turn, this might offer avenues to develop effective treatment strategies to improve the cognitive deficits often observed in many debilitating neurological disorders and diseases and in neurodegeneration.


Assuntos
Aprendizagem , Tálamo , Animais , Masculino , Humanos , Macaca mulatta , Aprendizagem/fisiologia , Tálamo/fisiologia , Córtex Pré-Frontal/fisiologia , Vias Neurais/fisiologia
2.
J Pediatr Hematol Oncol ; 45(1): e128-e130, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35700413

RESUMO

Biallelic variants in DI3SL2 cause Perlman Syndrome, associated increased risk for Wilms tumor. Cutis Marmorata Telangiectatica Congenita (CMTC) is a rare congenital disorder characterized by cutaneous vascular anomalies. We report a 2-year-old boy with both Wilms tumor and CMTC. Genetic testing, prompted by his complex presentation, revealed 1 somatic mutation and 1 familial germline mutation in the DIS3L2 gene, suggesting a 2-hit causation of Wilms tumor. Separately, a single GNA11 somatic mutation was identified to explain the CMTC. We suggest that genetic testing for germline mutations associated with Wilms tumor susceptibility be considered even in cases without known family history.


Assuntos
Livedo Reticular , Telangiectasia , Tumor de Wilms , Masculino , Humanos , Pré-Escolar , Telangiectasia/genética , Telangiectasia/complicações , Telangiectasia/congênito , Livedo Reticular/complicações , Mutação , Tumor de Wilms/genética , Tumor de Wilms/complicações , Doenças Raras/complicações , Exorribonucleases/genética
3.
Adv Exp Med Biol ; 1423: 11-20, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37525029

RESUMO

The fornix, the limbic system's white matter tract connecting the extended hippocampal system to subcortical structures of the medial diencephalon, is strongly associated with learning and memory in humans and nonhuman primates (NHPs). Here, we sought to investigate alterations in structural connectivity across key cortical and subcortical regions after fornix transection in NHPs. We collected diffusion-weighted MRI (dMRI) data from three macaque monkeys that underwent bilateral fornix transection during neurosurgery and from four age- and cohort-matched control macaques that underwent surgery to implant a head-post but remained neurologically intact. dMRI data were collected from both groups at two time points, before and after the surgeries, and scans took place at around the same time for the two groups. We used probabilistic tractography and employed the number of tracking streamlines to quantify connectivity across our regions of interest (ROIs), in all dMRI sessions. In the neurologically intact monkeys, we observed high connectivity across certain ROIs, including the CA3 hippocampal subfield with the retrosplenial cortex (RSC), the anterior thalamus with the RSC, and the RSC with the anterior cingulate cortex (ACC). However, we found that, compared to the control group, the fornix-transected monkeys showed marked, significant, connectivity changes including increases between the anterior thalamus and the ACC and between the CA3 and the ACC, as well as decreases between the CA3 and the RSC. Our results highlight cortical and subcortical network changes after fornix transection and identify candidate indirect connectivity routes that may support memory functions after damage and/or neurodegeneration.


Assuntos
Imagem de Tensor de Difusão , Fórnice , Animais , Humanos , Fórnice/diagnóstico por imagem , Fórnice/cirurgia , Hipocampo/diagnóstico por imagem , Hipocampo/cirurgia , Giro do Cíngulo , Macaca mulatta , Vias Neurais/diagnóstico por imagem
4.
Hosp Pharm ; 58(6): 605-613, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38560542

RESUMO

Background: Increasing evidence suggests that administration of combination vancomycin and piperacillin-tazobactam (VPT) increases the incidence of acute kidney injury (AKI) beyond that of vancomycin alone. But these investigations have not evaluated AKI risk specifically in an increasingly prevalent obese population in whom VPT pharmacokinetics are altered. Objective: To evaluate AKI risk with VPT administration to patients with obesity. Methods: We conducted a multicenter retrospective study of obese patients admitted to 2 separate academic teaching hospitals from January 2010 to December 2021, who received VPT, or vancomycin plus either cefepime, meropenem, or ceftazidime. The primary outcome evaluated AKI when patients were treated with or without VPT. Results: A total of 227 patients were evaluated (114 in VPT, vs 113 in control group). Overall, body mass index (35.6 kg/m2 ± 4.8vs 36.1 kg/m2 ± 5.2; P = .44) was similar between the VPT and control groups respectively. Total vancomycin dose on day 1 of antibiotic therapy (3,432 mg ± 935 vs 2,732 mg ± 912; P < .01) and nephrotoxin administration (75.4% vs 62.8%; P = .04) were higher in the VPT group. Incidence of AKI was higher in the VPT group (37.7%vs 14.2%; P = .01) and on regression analysis VPT was predictive of developing AKI (OR = 3.9; 95% CI = 2.0-7.7; P < .01). Conclusion and Relevance: In this retrospective study, the incidence of AKI was increased in obese patients receiving therapy with VPT. Vancomycin combination therapy with ceftazidime, cefepime, and meropenem appeared to be safe and was associated with less nephrotoxicity. Cautious use of VPT and further investigation with larger studies are warranted in this area.

5.
Clin Endocrinol (Oxf) ; 96(4): 499-512, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34558728

RESUMO

OBJECTIVE: Phaeochromocytomas and paragangliomas (PPGL) are rare, but strongly heritable tumours. Variants in succinate dehydrogenase (SDH) subunits are identified in approximately 25% of cases. However, clinical and genetic information of patients with SDHC variants are underreported. DESIGN: This retrospective case series collated data from 18 UK Genetics and Endocrinology departments. PATIENTS: Both asymptomatic and disease-affected patients with confirmed SDHC germline variants are included. MEASUREMENTS: Clinical data including tumour type and location, surveillance outcomes and interventions, SDHC genetic variant assessment, interpretation, and tumour risk calculation. RESULTS: We report 91 SDHC cases, 46 probands and 45 non-probands. Fifty-one cases were disease-affected. Median age at genetic diagnosis was 43 years (range: 11-79). Twenty-four SDHC germline variants were identified including six novel variants. Head and neck paraganglioma (HNPGL, n = 30, 65.2%), extra-adrenal paraganglioma (EAPGL, n = 13, 28.2%) and phaeochromocytomas (PCC) (n = 3, 6.5%) were present. One case had multiple PPGLs. Malignant disease was reported in 19.6% (9/46). Eight cases had non-PPGL SDHC-associated tumours, six gastrointestinal stromal tumours (GIST) and two renal cell cancers (RCC). Cumulative tumour risk (95% CI) at age 60 years was 0.94 (CI: 0.79-0.99) in probands, and 0.16 (CI: 0-0.31) in non-probands, respectively. CONCLUSIONS: This study describes the largest cohort of 91 SDHC patients worldwide. We confirm disease-affected SDHC variant cases develop isolated HNPGL disease in nearly 2/3 of patients, EAPGL and PCC in 1/3, with an increased risk of GIST and RCC. One fifth developed malignant disease, requiring comprehensive lifelong tumour screening and surveillance.


Assuntos
Neoplasias das Glândulas Suprarrenais , Carcinoma de Células Renais , Tumores do Estroma Gastrointestinal , Neoplasias Renais , Paraganglioma , Feocromocitoma , Neoplasias das Glândulas Suprarrenais/genética , Feminino , Mutação em Linhagem Germinativa/genética , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Paraganglioma/genética , Paraganglioma/patologia , Feocromocitoma/genética , Feocromocitoma/patologia , Estudos Retrospectivos , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismo , Reino Unido
6.
J Neurosci ; 40(41): 7887-7901, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32900835

RESUMO

The frontal cortex and temporal lobes together regulate complex learning and memory capabilities. Here, we collected resting-state functional and diffusion-weighted MRI data before and after male rhesus macaque monkeys received extensive training to learn novel visuospatial discriminations (reward-guided learning). We found functional connectivity changes in orbitofrontal, ventromedial prefrontal, inferotemporal, entorhinal, retrosplenial, and anterior cingulate cortices, the subicular complex, and the dorsal, medial thalamus. These corticocortical and thalamocortical changes in functional connectivity were accompanied by related white matter structural alterations in the uncinate fasciculus, fornix, and ventral prefrontal tract: tracts that connect (sub)cortical networks and are implicated in learning and memory processes in monkeys and humans. After the well-trained monkeys received fornix transection, they were impaired in learning new visuospatial discriminations. In addition, the functional connectivity profile that was observed after the training was altered. These changes were accompanied by white matter changes in the ventral prefrontal tract, although the integrity of the uncinate fasciculus remained unchanged. Our experiments highlight the importance of different communication relayed among corticocortical and thalamocortical circuitry for the ability to learn new visuospatial associations (learning-to-learn) and to make reward-guided decisions.SIGNIFICANCE STATEMENT Frontal neural networks and the temporal lobes contribute to reward-guided learning in mammals. Here, we provide novel insight by showing that specific corticocortical and thalamocortical functional connectivity is altered after rhesus monkeys received extensive training to learn novel visuospatial discriminations. Contiguous white matter fiber pathways linking these gray matter structures, namely, the uncinate fasciculus, fornix, and ventral prefrontal tract, showed structural changes after completing training in the visuospatial task. Additionally, different patterns of functional and structural connectivity are reported after removal of subcortical connections within the extended hippocampal system, via fornix transection. These results highlight the importance of both corticocortical and thalamocortical interactions in reward-guided learning in the normal brain and identify brain structures important for memory capabilities after injury.


Assuntos
Córtex Cerebral/fisiologia , Condicionamento Operante/fisiologia , Discriminação Psicológica/fisiologia , Vias Neurais/fisiologia , Tálamo/fisiologia , Substância Branca/fisiologia , Animais , Mapeamento Encefálico , Córtex Cerebral/diagnóstico por imagem , Fórnice/fisiologia , Macaca mulatta , Imageamento por Ressonância Magnética , Masculino , Memória/fisiologia , Vias Neurais/diagnóstico por imagem , Recompensa , Percepção Espacial/fisiologia , Tálamo/diagnóstico por imagem , Percepção Visual/fisiologia , Substância Branca/diagnóstico por imagem
7.
Neuroimage ; 229: 117700, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33418072

RESUMO

Scientific excellence is a necessity for progress in biomedical research. As research becomes ever more international, establishing international collaborations will be key to advancing our scientific knowledge. Understanding the similarities in standards applied by different nations to animal research, and where the differences might lie, is crucial. Cultural differences and societal values will also contribute to these similarities and differences between countries and continents. Our overview is not comprehensive for all species, but rather focuses on non-human primate (NHP) research, involving New World marmosets and Old World macaques, conducted in countries where NHPs are involved in neuroimaging research. Here, an overview of the ethics and regulations is provided to help assess welfare standards amongst primate research institutions. A comparative examination of these standards was conducted to provide a basis for establishing a common set of standards for animal welfare. These criteria may serve to develop international guidelines, which can be managed by an International Animal Welfare and Use Committee (IAWUC). Internationally, scientists have a moral responsibility to ensure excellent care and welfare of their animals, which in turn, influences the quality of their research. When working with animal models, maintaining a high quality of care ("culture of care") and welfare is essential. The transparent promotion of this level of care and welfare, along with the results of the research and its impact, may reduce public concerns associated with animal experiments in neuroscience research.


Assuntos
Acesso à Informação/ética , Bem-Estar do Animal/ética , Pesquisa Biomédica/ética , Internacionalidade , Neurociências/ética , Bem-Estar do Animal/legislação & jurisprudência , Animais , Pesquisa Biomédica/legislação & jurisprudência , Membro de Comitê , Humanos , Neurociências/legislação & jurisprudência , Primatas
8.
Neuroimage ; 235: 118017, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33794355

RESUMO

Brain perturbation studies allow detailed causal inferences of behavioral and neural processes. Because the combination of brain perturbation methods and neural measurement techniques is inherently challenging, research in humans has predominantly focused on non-invasive, indirect brain perturbations, or neurological lesion studies. Non-human primates have been indispensable as a neurobiological system that is highly similar to humans while simultaneously being more experimentally tractable, allowing visualization of the functional and structural impact of systematic brain perturbation. This review considers the state of the art in non-human primate brain perturbation with a focus on approaches that can be combined with neuroimaging. We consider both non-reversible (lesions) and reversible or temporary perturbations such as electrical, pharmacological, optical, optogenetic, chemogenetic, pathway-selective, and ultrasound based interference methods. Method-specific considerations from the research and development community are offered to facilitate research in this field and support further innovations. We conclude by identifying novel avenues for further research and innovation and by highlighting the clinical translational potential of the methods.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Neuroimagem/métodos , Animais , Humanos , Optogenética , Primatas
9.
Clin Genet ; 99(4): 547-557, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33381861

RESUMO

SATB2-Associated syndrome (SAS) is an autosomal dominant, multisystemic, neurodevelopmental disorder due to alterations in SATB2 at 2q33.1. A limited number of individuals with 2q33.1 contiguous deletions encompassing SATB2 (ΔSAS) have been described in the literature. We describe 17 additional individuals with ΔSAS, review the phenotype of 33 previously published individuals with 2q33.1 deletions (n = 50, mean age = 8.5 ± 7.8 years), and provide a comprehensive comparison to individuals with other molecular mechanisms that result in SAS (non-ΔSAS). Individuals in the ΔSAS group were often underweight for age (20/41 = 49%) with a progressive decline in weight (95% CI = -2.3 to -1.1, p < 0.0001) and height (95% CI = -2.3 to -1.0, p < 0.0001) Z-score means from birth to last available measurement. ΔSAS individuals were often noted to have a broad spectrum of facial dysmorphism. A composite image of ΔSAS individuals generated by automated image analysis was distinct as compared to matched controls and non-ΔSAS individuals. We also present additional genotype-phenotype correlations for individuals in the ΔSAS group such as an increased risk for aortic root/ascending aorta dilation and primary pulmonary hypertension for those individuals with contiguous gene deletions that include COL3A1/COL5A2 and BMPR2, respectively. Based on these findings, we provide additional care recommendations for individuals with ΔSAS variants.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 2/genética , Proteínas de Ligação à Região de Interação com a Matriz/deficiência , Fatores de Transcrição/deficiência , Adulto , Criança , Pré-Escolar , Cromossomos Humanos Par 2/ultraestrutura , Colágeno Tipo III/deficiência , Colágeno Tipo III/genética , Colágeno Tipo V/deficiência , Colágeno Tipo V/genética , Nanismo/genética , Face/anormalidades , Feminino , Estudos de Associação Genética , Idade Gestacional , Humanos , Hipertensão Pulmonar/genética , Lactente , Masculino , Proteínas de Ligação à Região de Interação com a Matriz/genética , Microcefalia/genética , Fenótipo , Magreza/genética , Fatores de Transcrição/genética
10.
Clin Endocrinol (Oxf) ; 94(3): 513-520, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32978985

RESUMO

OBJECTIVE: Dissatisfaction with treatment and impaired quality of life (QOL) are reported among people with treated hypothyroidism. We aimed to gain insight into this. DESIGN AND PATIENTS: We conducted an online survey of individuals with self-reported hypothyroidism. RESULTS: Nine hundred sixty-nine responses were analysed. Dissatisfaction with treatment was common (77.6%), and overall QOL scores were low. Patient satisfaction did not correlate with type of thyroid hormone treatment, but treatment with combination levothyroxine (L-T4) and liothyronine (L-T3) or with desiccated thyroid extract (DTE) was associated with significantly better reported QOL than L-T4 or L-T3 monotherapies (P < .001); however, multivariate analysis inclusive of other clinical parameters failed to confirm an association between type of thyroid hormone treatment and QOL or satisfaction. Multivariate analysis showed positive correlations between satisfaction and age (P = .026), male gender (P = .011), being under the care of a thyroid specialist (P < .001), family doctor (GP) prescribing DTE or L-T4 + L-T3 or L-T3 (P < .001) and being well informed about hypothyroidism (P < .001); negative correlations were observed between satisfaction and negative experiences with L-T4 (P < .001) and expectations for more support from the GP (P < .001), for L-T4 to resolve all symptoms (P = .004), and to be referred to a thyroid specialist (P < .001). For QOL, positive correlations were with male gender (P = .011) and duration of hypothyroidism (P = .002); negative correlations were with age (P = .027), visiting the GP more than 3 times before diagnosis (P < .001), sourcing DTE or L-T3 independently (P = .014), negative experiences with L-T4 (P = .013), having expectations for L-T4 to resolve all symptoms (P < .001) and of more support from the GP (P = .006). CONCLUSIONS: Multiple parameters including prior healthcare experiences and expectations influence satisfaction with hypothyroidism treatment and QOL. Focusing on enhancing the patient experience and clarifying expectations at diagnosis may improve satisfaction and QOL.


Assuntos
Hipotireoidismo , Satisfação do Paciente , Humanos , Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/psicologia , Masculino , Qualidade de Vida , Tireotropina , Tiroxina/uso terapêutico , Tri-Iodotironina
11.
Neurobiol Learn Mem ; 185: 107525, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555510

RESUMO

Retrosplenial cortex (RSC) lies at the interface between sensory and cognitive networks in the brain and mediates between these, although it is not yet known how. It has two distinct subregions, granular (gRSC) and dysgranular (dRSC). The present study investigated how these subregions differ with respect to their electrophysiology and thalamic connectivity, as a step towards understanding their functions. The gRSC is more closely connected to the hippocampal formation, in which theta-band local field potential oscillations are prominent. We, therefore, compared theta-rhythmic single-unit activity between the two RSC subregions and found, mostly in gRSC, a subpopulation of non-directional cells with spiking activity strongly entrained by theta oscillations, suggesting a stronger coupling of gRSC to the hippocampal system. We then used retrograde tracers to test for differential inputs to RSC from the anteroventral thalamus (AV). We found that gRSC and dRSC differ in their afferents from two AV subfields: dorsomedial (AVDM) and ventrolateral (AVVL). Specifically: (1) as a whole AV projects more strongly to gRSC; (2) AVVL targets both gRSC and dRSC, while AVDM provides a selective projection to gRSC, (3) the gRSC projection is layer-specific: AVDM targets specifically gRSC superficial layers. These same AV projections are topographically organized with ventral AV neurons innervating rostral RSC and dorsal AV neurons innervating caudal RSC. These combined results suggest the existence of two distinct but interacting RSC subcircuits: one connecting AVDM to gRSC that may comprise part of the cognitive hippocampal system, and the other connecting AVVL to both RSC regions that may link hippocampal and perceptual regions. We suggest that these subcircuits are distinct to allow for differential weighting during integration of converging sensory and cognitive computations: an integration that may take place in thalamus, RSC, or both.


Assuntos
Córtex Cerebral/fisiologia , Giro do Cíngulo/fisiologia , Vias Neurais/fisiologia , Tálamo/fisiologia , Animais , Eletroencefalografia , Giro do Cíngulo/anatomia & histologia , Masculino , Vias Neurais/anatomia & histologia , Ratos , Ritmo Teta/fisiologia
12.
Postgrad Med J ; 96(1140): 589-593, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31874911

RESUMO

PURPOSE OF THE STUDY: The National Health Service is experiencing a recruitment crisis across many medical specialties. Diabetes and endocrinology (D&E) is failing to fill training posts with only 77%, 83% and 73% of posts filled overall in 2016, 2017 and 2018, respectively. STUDY DESIGN: We surveyed 316 final-year medical students and undifferentiated trainees (from foundation programme doctors to core medical trainees), across the South Thames, Northern and West Midlands deaneries in England to gain an understanding of perceptions of the specialty. RESULTS: 9% of respondents were considering a career in D&E. Factors such as 'being the medical registrar' (27%), being a 'non-procedural specialty' (23%) and 'looking after majority of general medical admissions' (22%) were cited as the most common reasons why D&E is an unattractive career choice. 51% reported inadequate exposure to D&E. Factors that made respondents more likely to want to pursue a career in D&E included having undertaken a placement in the specialty and having exposure to outpatient clinics. Methods to improve awareness and uptake, such as increased teaching and clinical exposure, and the opportunity to attend taster events were frequently highlighted. CONCLUSIONS: The results from this survey, the first of its kind on perceptions of D&E as a career pathway, reveal a worrying lack of interest in, and exposure to, D&E among current final-year medical students and undifferentiated trainees. These issues must be addressed in order to improve D&E recruitment rates.


Assuntos
Atitude do Pessoal de Saúde , Escolha da Profissão , Endocrinologia , Corpo Clínico Hospitalar , Estudantes de Medicina , Estágio Clínico , Competência Clínica , Diabetes Mellitus/terapia , Humanos , Internato e Residência , Medicina Estatal , Inquéritos e Questionários , Reino Unido
13.
J Genet Couns ; 29(6): 1041-1049, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32091143

RESUMO

Approximately one in three Ashkenazi Jews are carriers for an autosomal recessive Jewish genetic disease (JGD). However, studies indicate that most Jews are uneducated on this topic and obstetricians do not routinely offer carrier screening to Jewish patients. Both the Reform and Conservative movements of Judaism call for JGD education to take place within the synagogue; however, little is known about the extent of this education occurring today. An online survey was created for Reform and Conservative rabbis to assess the types of JGD education taking place within the synagogue. Additionally, the survey included questions to assess JGD knowledge and possible factors that could predict counseling activity and knowledge level. Of the 94 participants, 91% had provided education about JGDs to congregants, with 98.8% providing this education during premarital counseling sessions. For most respondents, explaining recessive inheritance pattern and carrier screening was the extent of the discussion. Additionally, the majority of rabbis scored below 50% on the knowledge portion of the survey, with an average score of 1.9/4. There were no statistically significant differences between JGD education in Reform vs. Conservative synagogues, and there were no statistically significant predictors of knowledge score or JGD education frequency. In conclusion, while the number of rabbis discussing this topic is encouraging, discussion topics were found to be limited and their knowledge of JGDs was found to be poor.


Assuntos
Triagem de Portadores Genéticos/métodos , Educação em Saúde/métodos , Judeus/genética , Adulto , Feminino , Humanos , Masculino , Inquéritos e Questionários
14.
Eur J Neurosci ; 49(8): 1041-1054, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30022540

RESUMO

Distributed brain networks govern adaptive decision-making, new learning and rapid updating of information. However, the functional contribution of the rhesus macaque monkey parvocellular nucleus of the mediodorsal thalamus (MDpc) in these key higher cognitive processes remains unknown. This study investigated the impact of MDpc damage in cognition. Preoperatively, animals were trained on an object-in-place scene discrimination task that assesses rapid learning of novel information within each session. Bilateral neurotoxic (NMDA and ibotenic acid) MDpc lesions did not impair new learning unless the monkey had also sustained damage to the magnocellular division of the MD (MDmc). Contralateral unilateral MDpc and MDmc damage also impaired new learning, while selective unilateral MDmc damage produced new learning deficits that eventually resolved with repeated testing. In contrast, during food reward (satiety) devaluation, monkeys with either bilateral MDpc damage or combined MDpc and MDmc damage showed attenuated food reward preferences compared to unoperated control monkeys; the selective unilateral MDmc damage left performance intact. Our preliminary results demonstrate selective dissociable roles for the two adjacent nuclei of the primate MD, namely, MDpc, as part of a frontal cortical network, and the MDmc, as part of a frontal-temporal cortical network, in learning, memory and the cognitive control of behavioural choices after changes in reward value. Moreover, the functional cognitive deficits produced after differing MD damage show that the different subdivisions of the MD thalamus support distributed neural networks to rapidly and fluidly incorporate task-relevant information, in order to optimise the animals' ability to receive rewards.


Assuntos
Tomada de Decisões/fisiologia , Aprendizagem por Discriminação/fisiologia , Núcleo Mediodorsal do Tálamo/fisiologia , Animais , Discriminação Psicológica/fisiologia , Feminino , Macaca mulatta , Masculino , Reconhecimento Visual de Modelos/fisiologia , Recompensa
15.
Am J Hum Genet ; 99(5): 1005-1014, 2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27745832

RESUMO

Periodontal Ehlers-Danlos syndrome (pEDS) is an autosomal-dominant disorder characterized by early-onset periodontitis leading to premature loss of teeth, joint hypermobility, and mild skin findings. A locus was mapped to an approximately 5.8 Mb region at 12p13.1 but no candidate gene was identified. In an international consortium we recruited 19 independent families comprising 107 individuals with pEDS to identify the locus, characterize the clinical details in those with defined genetic causes, and try to understand the physiological basis of the condition. In 17 of these families, we identified heterozygous missense or in-frame insertion/deletion mutations in C1R (15 families) or C1S (2 families), contiguous genes in the mapped locus that encode subunits C1r and C1s of the first component of the classical complement pathway. These two proteins form a heterotetramer that then combines with six C1q subunits. Pathogenic variants involve the subunit interfaces or inter-domain hinges of C1r and C1s and are associated with intracellular retention and mild endoplasmic reticulum enlargement. Clinical features of affected individuals in these families include rapidly progressing periodontitis with onset in the teens or childhood, a previously unrecognized lack of attached gingiva, pretibial hyperpigmentation, skin and vascular fragility, easy bruising, and variable musculoskeletal symptoms. Our findings open a connection between the inflammatory classical complement pathway and connective tissue homeostasis.


Assuntos
Complemento C1r/genética , Complemento C1s/genética , Síndrome de Ehlers-Danlos/genética , Deleção de Genes , Mutação de Sentido Incorreto , Periodontite/genética , Adolescente , Adulto , Criança , Pré-Escolar , Mapeamento Cromossômico , Cromossomos Humanos Par 12/genética , Síndrome de Ehlers-Danlos/diagnóstico , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Exoma , Feminino , Loci Gênicos , Humanos , Masculino , Linhagem , Periodontite/diagnóstico , Conformação Proteica , Adulto Jovem
16.
Clin Endocrinol (Oxf) ; 90(1): 170-174, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30281845

RESUMO

OBJECTIVE: B lymphocyte activating factor (BAFF), a member of the tumour necrosis factor superfamily, is essential for B cell activation, differentiation and survival. Elevated circulating BAFF levels have been found in patients with several autoimmune conditions, including Graves' disease. In addition, BAFF gene variants have been associated with Graves' disease in a Taiwanese cohort, and with several other autoimmune conditions in non-Taiwanese populations. DESIGN AND METHODS: We performed a case-control association study to investigate two BAFF polymorphisms (rs9514828 and rs4000607) in a UK cohort of 444 patients with Graves' disease. Genotype frequencies were compared to those from 447 local controls and more than 5000 healthy controls from the Wellcome Trust case-control consortium (WTCCC2). RESULTS: There was a significant difference in the frequency of the AA genotype at rs4000607 between the Graves' disease cohort and both the local controls (P = 0.045) and the WTCCC2 controls (P = 4.56 × 10-6 ). Furthermore, the frequency of the A allele was found to be increased in the Graves' disease group compared to WTCCC2 controls (P = 0.02, OR 1.20 (95% CI 1.03-1.41). No association was observed at the rs9514828 locus. CONCLUSION: Dysfunction of the humoral immune system is an obligatory pathophysiological component of Graves' disease, hence BAFF is an excellent functional candidate gene. We have demonstrated, for the first time, a significant association of the BAFF polymorphism rs4000607 with Graves' disease in a UK cohort. Further work to elucidate the role of BAFF in the pathogenesis of Graves' disease is now warranted.


Assuntos
Fator Ativador de Células B/genética , Doença de Graves/genética , Polimorfismo Genético , Alelos , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Reino Unido
17.
Pediatr Blood Cancer ; 66(4): e27578, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30548417

RESUMO

BACKGROUND: Topotecan is a chemotherapeutic agent that is active against many pediatric tumors. Although its effect is related to systemic exposure, the interpatient variability in systemic clearance makes it challenging to achieve desired topotecan targets. This study aims to evaluate the success of the pharmacokinetically (PK) guided dosing process, which was used to achieve a target topotecan area under the concentration-time curve (AUC). METHODS: Patients received an empiric topotecan dosage on the first day; the topotecan lactone AUC was determined, and based upon these values the topotecan dosage was adjusted. The success rates of both the empiric and PK-guided strategies were calculated. Patient-specific covariates were collected to explain variability observed in the empiric and PK-guided results. A simulation study was performed to assess the differences in cumulative topotecan dosage and systemic exposure between a PK-guided and standard dosing approach. RESULTS: Data were collected from nine clinical trials open from 1996 to 2016 (n = 232 patients). The empiric dosing success rate was 35.5%, while the PK-guided rate was 64.4%. A difference in mean serum creatinine was observed between successful empiric studies and those above the AUC target. Compared to a standard dosing approach, the PK-guided group had a higher average cumulative dosage and systemic exposure. CONCLUSION: The low empiric dosing success rate indicates that additional studies are needed to refine the initial topotecan dosage. The role of renal function, measured as serum creatinine, remains to be elucidated. However, the PK-guided targeting success rate highlighted the need to account for variable topotecan systemic clearance.


Assuntos
Antineoplásicos , Neoplasias , Topotecan , Adolescente , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Área Sob a Curva , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Estudos Retrospectivos , Topotecan/administração & dosagem , Topotecan/farmacocinética
18.
BMC Nephrol ; 20(1): 167, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088392

RESUMO

BACKGROUND: The influence of pre- or postprandial administration on pharmacokinetics of cyclosporine is supposed to be less in gel-based formulations than in microemulsions. This study was designed to investigate the influence of a high-fat meal on the pharmacokinetic profile of the two cyclosporine containing formulations Ciclosporin Pro (gel-based emulsion) and Sandimmun®Optoral (microemulsion) in renal transplant recipients. METHODS: A randomized, open-label, repeated-measurement, comparative phase IV trial was conducted with two sequence groups for nutrition condition (fasting→fed, fed→fasting) and two treatment phases (Sandimmun® Optoral → Ciclosporin Pro), each covering both nutrition conditions. Primary pharmacokinetic variable of interest was the reduction of bioavailability due to high-fat food compared to fasting conditions measured by the difference D of ln-transformed bioavailability variables (AUCSS, τ, Css, max, und Css, min). RESULTS: A nutrition effect was found for both study medications with respect to the parameters AUCSS, τ and CSS, max, but not to CSS, min. The reduction of bioavailability caused by high-fat food was not significantly different for Sandimmun®Optoral and Ciclosporin Pro. CONCLUSIONS: An effect of high-fat breakfast prior to the morning dose on AUCSS, τ and CSS, max was found for Sandimmun® Optoral and for Ciclosporin Pro. Trough level monitoring did not capture ingestion-related variability. Conversion to Ciclosporin Pro seems to be safe with regard to intra-individual pharmacokinetic variability. TRIAL REGISTRATION: EudraCT No. 2009-011354-18 (29th April 2019).


Assuntos
Ciclosporina/metabolismo , Dieta Hiperlipídica , Composição de Medicamentos/métodos , Jejum/metabolismo , Imunossupressores/metabolismo , Transplante de Rim , Adulto , Idoso , Disponibilidade Biológica , Dieta Hiperlipídica/tendências , Indústria Farmacêutica/tendências , Feminino , Humanos , Transplante de Rim/tendências , Masculino , Pessoa de Meia-Idade , Método Simples-Cego
19.
J Genet Couns ; 28(5): 962-973, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31290196

RESUMO

Genetic counseling assistants (GCAs) have the potential to address the high demand for genetic counselors by promoting task-sharing, increasing genetic counselor efficiency, and allowing for higher level duties to be optimized by genetic counselors. However, little research has been published on the role of GCAs. This study explored current tasks of GCAs in the United States, the appropriateness of those tasks, the perceived impact on the profession, and how these findings compared between genetic counselors with and without GCAs. Full members of the National Society of Genetic Counselors (NSGC) with and without experience working with GCAs were recruited via the NSGC Student Research listserv to complete an online survey and 271 surveys were analyzed. Participants working in both clinical and laboratory settings and in all primary specialties reported working with GCAs (n = 131); GCAs were reported to frequently perform clerical tasks but were involved less often in clinical tasks such as calling patients with genetic test results. There was no difference between participants with GCAs and those without GCAs in tasks they reported GCAs are or may be performing, yet participants without GCAs believed GCAs performed more tasks on average than those with GCAs reported (p < 0.001). Participants did not differ on the appropriateness of tasks, reporting clerical tasks as more appropriate for GCAs than clinically involved tasks, with the exception of calling patients with variant of uncertain significance (VUS) results in which more participants working with GCAs reported it as an appropriate task (13%) than those without GCAs (4%; p < 0.05). Review of open-ended responses revealed themes pertaining to primary limitations, benefits, and concerns of the GCA role. The most commonly reported concern about GCAs was their poorly defined scope of practice (n = 182). Other reported limitations included a heavy workload, lack of training, and lack of experience for GCAs while the benefits of working with GCAs included increased time available for higher level duties, patient volumes, and efficiency. These data provide genetic counselors, their institutions, and the NSGC with a more generalizable understanding of current GCA roles on a national level, across specialties. Additionally, these data may help establish a scope of practice for GCAs by creating a baseline job description for genetic counselors and their institutions interested in implementing a GCA into their practice to increase patient access to genetic counseling services. It is recommended that further research objectively quantify the value added by GCAs using efficiency metrics and further clarify the role of laboratory GCAs.


Assuntos
Conselheiros , Aconselhamento Genético , Aconselhamento/métodos , Feminino , Aconselhamento Genético/métodos , Humanos , Descrição de Cargo , Masculino , Inquéritos e Questionários , Estados Unidos , Recursos Humanos
20.
Vet Surg ; 48(5): 890-896, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30729544

RESUMO

OBJECTIVE: To describe the surgical treatment and short- and long-term outcome of young pot-bellied pigs with penile prolapse. STUDY DESIGN: Short case series. ANIMALS: Five young castrated Vietnamese pot-bellied pigs. METHODS: Five Vietnamese pot-bellied pigs presented with penile prolapse of several weeks duration. No other abnormalities were found at physical examination. Under general anesthesia, phallopexy with or without combined urethropexy was performed successfully in all cases. RESULTS: All pigs were discharged from the hospital. One pig required a second urethropexy the day after the initial surgery to improve positioning of the penis in the prepuce. Long-term outcome was available in 4 cases. Penile prolapse resolved in the 4 cases available for follow-up, and the owners were satisfied with the cosmetic outcome of the procedure. CONCLUSION: Penile prolapse was successfully corrected in 5 pot-bellied pigs by using 2 different phallopexy techniques. The procedure was combined with urethropexy in 3 pigs. Long-term outcome was excellent in the 4 cases available for follow-up. CLINICAL IMPACT: This is the first report describing the use of phallopexy with or without urethropexy for successful treatment of penile prolapse in young pot-bellied pigs. Two different phallopexy techniques were effectively used in this report. The etiology of penile prolapse in pot-bellied pigs remains unknown.


Assuntos
Doenças do Pênis/veterinária , Doenças dos Suínos/cirurgia , Animais , Masculino , Doenças do Pênis/patologia , Doenças do Pênis/cirurgia , Prolapso , Suínos , Uretra/cirurgia
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