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1.
Ann Neurol ; 94(4): 632-646, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37431188

RESUMO

OBJECTIVE: Microtubule-associated protein tau (MAPT) mutations cause frontotemporal lobar degeneration, and novel biomarkers are urgently needed for early disease detection. We used task-free functional magnetic resonance imaging (fMRI) mapping, a promising biomarker, to analyze network connectivity in symptomatic and presymptomatic MAPT mutation carriers. METHODS: We compared cross-sectional fMRI data between 17 symptomatic and 39 presymptomatic carriers and 81 controls with (1) seed-based analyses to examine connectivity within networks associated with the 4 most common MAPT-associated clinical syndromes (ie, salience, corticobasal syndrome, progressive supranuclear palsy syndrome, and default mode networks) and (2) whole-brain connectivity analyses. We applied K-means clustering to explore connectivity heterogeneity in presymptomatic carriers at baseline. Neuropsychological measures, plasma neurofilament light chain, and gray matter volume were compared at baseline and longitudinally between the presymptomatic subgroups defined by their baseline whole-brain connectivity profiles. RESULTS: Symptomatic and presymptomatic carriers had connectivity disruptions within MAPT-syndromic networks. Compared to controls, presymptomatic carriers showed regions of connectivity alterations with age. Two presymptomatic subgroups were identified by clustering analysis, exhibiting predominantly either whole-brain hypoconnectivity or hyperconnectivity at baseline. At baseline, these two presymptomatic subgroups did not differ in neuropsychological measures, although the hypoconnectivity subgroup had greater plasma neurofilament light chain levels than controls. Longitudinally, both subgroups showed visual memory decline (vs controls), yet the subgroup with baseline hypoconnectivity also had worsening verbal memory and neuropsychiatric symptoms, and extensive bilateral mesial temporal gray matter decline. INTERPRETATION: Network connectivity alterations arise as early as the presymptomatic phase. Future studies will determine whether presymptomatic carriers' baseline connectivity profiles predict symptomatic conversion. ANN NEUROL 2023;94:632-646.


Assuntos
Demência Frontotemporal , Proteínas tau , Humanos , Estudos Transversais , Proteínas tau/genética , Encéfalo/diagnóstico por imagem , Mutação/genética , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética , Demência Frontotemporal/genética , Biomarcadores
2.
Pediatr Res ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750294

RESUMO

BACKGROUND: Nasogastric tube (NGT) feeding is used for children unable to tolerate adequate nutrition orally to sustain growth and development. This vulnerable population is at risk of gaps in care because they often lack a medical home due to the transitional nature of the technology. This study explores perspectives and challenges of family caregivers (FCs) of children requiring NGTs transitioning from hospital to home. METHODS: Semi-structured qualitative interviews were conducted with FCs at the Hospital for Sick Children and Children's Hospital of Eastern Ontario. Research ethics approval was obtained (SK REB# 1000064641, CHEO REB# 19/133X). Written informed consent was obtained. RESULTS: Thirteen interviews revealed FCs feeling overwhelmed and uncomfortable with first communication of the NGT but learned to manage NGTs with training and virtual care support over time. Initial transition home was described as challenging due to physical, emotional, and financial strain associated with constant management of NGTs. CONCLUSIONS: Our study describes the importance of emotional support and additional time for decision making during initial communication to FCs of their child's NGT need, and access to specialized healthcare professionals after transitioning home. Future programs should focus on personalized education and psychosocial support for FCs of children with NGTs at home. IMPACT: This study delves into the challenges faced by family caregivers (FCs) of children requiring nasogastric tube (NGT) feeding when returning home from the hospital. There is a pressing need for more time for FC decision-making and emotional support during the initial communication of the need for an NGT for their child. In addition, FCs require ongoing 24/7 support including access to healthcare professionals specialized in NGT care after the initial transition home. The study highlights the need for personalized education and psychosocial supports for FCs of children with NGTs to improve their experiences at home.

3.
Mol Psychiatry ; 27(10): 4181-4190, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35896619

RESUMO

Probing naturally-occurring, reciprocal genomic copy number variations (CNVs) may help us understand mechanisms that underlie deviations from typical brain development. Cross-sectional studies have identified prominent reductions in cortical surface area (SA) and increased cortical thickness (CT) in 22q11.2 deletion carriers (22qDel), with the opposite pattern in duplication carriers (22qDup), but the longitudinal trajectories of these anomalies-and their relationship to clinical symptomatology-are unknown. Here, we examined neuroanatomic changes within a longitudinal cohort of 261 22q11.2 CNV carriers and demographically-matched typically developing (TD) controls (84 22qDel, 34 22qDup, and 143 TD; mean age 18.35, ±10.67 years; 50.47% female). A total of 431 magnetic resonance imaging scans (164 22qDel, 59 22qDup, and 208 TD control scans; mean interscan interval = 20.27 months) were examined. Longitudinal FreeSurfer analysis pipelines were used to parcellate the cortex and calculate average CT and SA for each region. First, general additive mixed models (GAMMs) were used to identify regions with between-group differences in developmental trajectories. Secondly, we investigated whether these trajectories were associated with clinical outcomes. Developmental trajectories of CT were more protracted in 22qDel relative to TD and 22qDup. 22qDup failed to show normative age-related SA decreases. 22qDel individuals with psychosis spectrum symptoms showed two distinct periods of altered CT trajectories relative to 22qDel without psychotic symptoms. In contrast, 22q11.2 CNV carriers with autism spectrum diagnoses showed early alterations in SA trajectories. Collectively, these results provide new insights into altered neurodevelopment in 22q11.2 CNV carriers, which may shed light on neural mechanisms underlying distinct clinical outcomes.


Assuntos
Variações do Número de Cópias de DNA , Transtornos Psicóticos , Humanos , Feminino , Masculino , Variações do Número de Cópias de DNA/genética , Estudos Transversais , Imageamento por Ressonância Magnética/métodos , Transtornos Psicóticos/patologia
4.
J Esthet Restor Dent ; 35(1): 206-214, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36628940

RESUMO

OBJECTIVE: The biaxial nature of the anterior maxilla poses a surgical and restorative challenge in implant dentistry. The present study sought to investigate the apical socket perforation rate (ASPR) from a simulated uniaxial implant placement and to determine the effect of implant length and diameter on ASPR when a uniaxial implant was placed compared with the orientation of the pre-existing dual-axis implant. MATERIAL AND METHOD: Cone beam computed tomography (CBCT) scans from the database of three private practices were searched for patients who received dual-axis implants within the esthetic zone in immediate tooth replacement therapy. A uniaxial implant was virtually placed using the pre-existing screw access channel of the dual-axis implant as a reference. The closest length and diameter were selected for the simulated implant. ASPR by the uniaxial implant was recorded. In addition, the affordable maximum length of a corresponding uniaxial implant that would avoid apical socket perforation was measured. RESULT: Eighty-one patients with a total of 101 dual-axis dental implants were selected for analysis. A simulated virtual surgical planning with uniaxial implants revealed high ASPR (48.51%). When the length of the uniaxial implant was reduced to 11 and 9 mm, ASPR was decreased to 41.58% and 20.79%, respectively. CONCLUSION: Dual-axis implant design effectively evades anatomical challenges in the anterior maxilla (esthetic zone). Considering the current evidence, efforts should be made to carefully consider the angular disparity between the extraction socket-alveolus complex and the future restorative emergence so that a harmonious biologic-esthetic result may be more predictably and consistently obtained.


Assuntos
Implantes Dentários para Um Único Dente , Carga Imediata em Implante Dentário , Humanos , Maxila/cirurgia , Alvéolo Dental/cirurgia , Tomografia Computadorizada de Feixe Cônico/métodos , Ligamento Periodontal , Carga Imediata em Implante Dentário/métodos , Extração Dentária
5.
BMC Ophthalmol ; 22(1): 23, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35031016

RESUMO

BACKGROUND: Peripheral iridectomy (PI), routinely performed during glaucoma filtration surgery, may contribute to scarring. This study aims to determine whether PI alters the concentrations of VEGF-A and TGF-ß isoforms in the rabbit aqueous humour. METHODS: Anterior chamber paracentesis (ACP) was performed in both eyes of six New Zealand white rabbits, with additional surgical PI performed in the right eyes. Eyes were examined on postoperative days (PODs) 1, 7, 30 and 60 by means of the tonopen, slit-lamp biomicroscopy, and bead-based cytokine assays for TGF-ß and VEGF-A concentrations in the aqueous humor. RESULTS: ACP caused a significant reduction in intraocular pressure (IOP) from mean preoperative 11.47 ± 1.01 mmHg to 5.67 ± 1.63 mmHg on POD 1 while PI did not cause further IOP reduction. Limbal conjunctival vasculature appeared slightly increased on POD 1 in both ACP and PI eyes with PI also causing mild bleeding from damaged iris vessels. Two PI eyes developed fibrinous anterior chamber reaction and/ or peripheral anterior synechiae. Aqueous VEGF-A levels were not significantly different between eyes treated with ACP and PI. Aqueous TGF-ß concentrations distributed in the ratio of 4:800:1 for TGF-ß1:TGF-ß2:TGF-ß3 respectively. While aqueous TGF-ß2 was not significantly induced by either procedure at any time point, TGF-ß1 and TGF-ß3 were significantly induced above baseline levels by PI on POD 1. CONCLUSION: PI increases the risk of inflammation. The combined induction of aqueous TGF-ß1 and TGF-ß3 by PI in glaucoma surgery may impact surgery success in glaucoma subtypes sensitive to these isoforms.


Assuntos
Humor Aquoso , Fator A de Crescimento do Endotélio Vascular , Animais , Pressão Intraocular , Iridectomia , Iris/cirurgia , Coelhos
6.
J Esthet Restor Dent ; 34(1): 167-180, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34939298

RESUMO

OBJECTIVE: One of the most common complications with dental implants placed in the smile zone is the development of mid-facial recession, creating an undesirable esthetic result. When deciding how to remediate these clinical scenarios, the question becomes whether it may be feasible to save the problematic implant or if it is more predictable to remove the implant and start all over again. However, patients may be invested emotionally, physically, and financially in the implant and remediation may be a viable option depending on the diagnosis of the specific issues at hand and multi-disciplinary clinical execution. CLINICAL SIGNIFICANCE: What is crucial to understand in order to remediate these cases is answering four separate criteria: (1) is the implant in a restorable position, (2) is the implant healthy, (3) is the implant placed at an adequate depth, and (4) are components available to restore the implant. CONCLUSIONS: Two different clinical reports are presented that demonstrate various treatment remedies when saving implants in the esthetic zone.


Assuntos
Implantes Dentários para Um Único Dente , Implantação Dentária Endóssea , Estética Dentária , Humanos , Maxila/cirurgia , Resultado do Tratamento
7.
Neurobiol Dis ; 145: 105063, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32890771

RESUMO

Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) have a strong clinical, genetic and pathological overlap. This review focuses on the current understanding of structural, functional and molecular neuroimaging signatures of genetic FTD and ALS. We overview quantitative neuroimaging studies on the most common genes associated with FTD (MAPT, GRN), ALS (SOD1), and both (C9orf72), and summarize visual observations of images reported in the rarer genes (CHMP2B, TARDBP, FUS, OPTN, VCP, UBQLN2, SQSTM1, TREM2, CHCHD10, TBK1).


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico por imagem , Demência Frontotemporal/diagnóstico por imagem , Neuroimagem/métodos , Esclerose Lateral Amiotrófica/genética , Demência Frontotemporal/genética , Humanos
8.
J Neurol Neurosurg Psychiatry ; 90(9): 1005-1010, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31079065

RESUMO

OBJECTIVE: To investigate in-vivo cortical gyrification patterns measured by the local gyrification index (lGI) in presymptomatic c9orf72 expansion carriers compared with healthy controls, and investigate relationships between lGI and cortical thickness, an established morphometric measure of neurodegeneration. METHODS: We assessed cortical gyrification and thickness patterns in a cohort of 15 presymptomatic c9orf72 expansion carriers (age 43.7 ± 10.2 years, 9 females) compared with 67 (age 42.4 ± 12.4 years, 36 females) age and sex matched healthy controls using the dedicated Freesurfer pipeline. RESULTS: Compared with controls, presymptomatic carriers showed significantly lower lGI in left frontal and right parieto-occipital regions. Interestingly, those areas with abnormal gyrification in presymptomatic carriers showed no concomitant cortical thickness abnormality. Overall, for both presymptomatic carriers and healthy controls, gyrification and cortical thickness measures were not correlated, suggesting that gyrification captures a feature distinct from cortical thickness. CONCLUSIONS: Presymptomatic c9orf72 expansion carriers show regions of abnormally low gyrification as early as their 30s, decades before expected symptom onset. Cortical gyrification represents a novel grey matter metric distinctive from grey matter thickness or volume and detects differences in presymptomatic carriers at an early age.


Assuntos
Proteína C9orf72/genética , Córtex Cerebral/anormalidades , Heterozigoto , Adulto , Fatores Etários , Doenças Assintomáticas , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem
9.
Epilepsia ; 60(8): 1678-1688, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31283843

RESUMO

OBJECTIVE: To investigate intrathecal inflammation using cerebrospinal fluid (CSF) cytokines and chemokines in a subgroup of pediatric epilepsy patients with frequent daily seizures. METHODS: We measured 32 cytokines/chemokines using multiplex immunoassay in CSF collected from pediatric patients with febrile infection-related epilepsy syndrome (FIRES)/FIRES-related disorders (FRD; n = 6), febrile status epilepticus (FSE; n = 8), afebrile status epilepticus (ASE; n = 8), and chronic epilepsy with frequent daily seizures (n = 21) and compared the results with noninflammatory neurological disorders (NIND; n = 20) and encephalitis (n = 43). We also performed longitudinal CSF cytokine/chemokine studies in three cases with FIRES/FRD. RESULTS: The median age of onset of seizures was 2.4 years (range = 0.08-12.5). Median CSF timing from the onset of seizures was longer in chronic epilepsy (540 days), whereas FIRES, FSE, and ASE had CSF tested within 1-2 days of onset of seizures (P < .001). The elevation of cytokines/chemokines was higher in FIRES followed by FSE, when compared to chronic epilepsy and NIND controls. Th1-associated cytokines/chemokines (TNF-α, CXCL9, CXCL10, CXCL11), IL-6, CCL2, CCL19, and CXCL1 (P < .05) were elevated in FIRES, in contrast to the elevation of a broader network of cytokines/chemokines in encephalitis. The cytokines/chemokines (CXCL9, CXCL10, CXCL11, and CCL19) were elevated in FSE when compared to ASE despite the similar median seizure duration and timing of CSF testing in relation to seizures. Chronic epilepsy generally lacked significant elevation of cytokines/chemokines despite frequent daily seizures. The median concentrations of the cytokines/chemokines rapidly declined on serial testing during the course of illness in all three FIRES/FRD cases. SIGNIFICANCE: We identify significant differences in CSF cytokine/chemokine profile between FIRES/FRD and encephalitis. The prominent elevation of CSF cytokines and chemokines in FIRES/FRD and to a lesser extent FSE highlights that the cytokine/chemokine elevation is significantly associated with the etiology of the underlying process rather than purely reactive. However, it is unclear whether the immune activation contributes to the disease process.


Assuntos
Quimiocinas/líquido cefalorraquidiano , Citocinas/líquido cefalorraquidiano , Epilepsia/líquido cefalorraquidiano , Febre/complicações , Estado Epiléptico/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Epilepsia/etiologia , Feminino , Febre/líquido cefalorraquidiano , Humanos , Lactente , Inflamação/líquido cefalorraquidiano , Inflamação/complicações , Masculino , Convulsões/líquido cefalorraquidiano , Convulsões/etiologia , Estado Epiléptico/etiologia
10.
Clin J Sport Med ; 27(2): 179-182, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26867204

RESUMO

BACKGROUND: Concussion is an emerging public health concern, but care of patients with a concussion is presently unregulated in Canada. METHODS: Independent, blinded Google Internet searches were conducted for the terms "concussion" and "concussion clinic" and each of the Canadian provinces and territories. The first 10 to 15 concussion healthcare providers per province were identified. A critical appraisal of healthcare personnel and services offered on the provider's Web site was conducted. RESULTS: Fifty-eight concussion healthcare providers were identified using this search methodology. Only 40% listed the presence of an on-site medical doctor (M.D.) as a member of the clinical team. Forty-seven percent of concussion healthcare providers advertised access to a concussion clinic, program, or center on their Web site. Professionals designated as team leaders, directors, or presidents among concussion clinics, programs, and centers included a neuropsychologist (15%), sports medicine physician (7%), neurologist (4%), and neurosurgeon (4%). Services offered by providers included baseline testing (67%), physiotherapy (50%), and hyperbaric oxygen therapy (2%). CONCLUSIONS: This study indicates that there are numerous concussion healthcare providers in Canada offering diverse services with clinics operated by professionals with varying levels of training in traumatic brain injury. In some cases, the practices of these concussion clinics do not conform to current expert consensus guidelines.


Assuntos
Concussão Encefálica/terapia , Mão de Obra em Saúde/estatística & dados numéricos , Canadá , Mão de Obra em Saúde/normas , Humanos
11.
J Urol ; 196(4): 1196-200, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27164512

RESUMO

PURPOSE: Our aim was to test the feasibility of a set of quality of care indicators for urinary incontinence and at the same time measure the care provided to women with urinary incontinence in 2 clinical settings. MATERIALS AND METHODS: This was a pilot test of a set of quality of care indicators. A total of 20 quality of care indicators were previously developed using the RAND Appropriateness Method. These quality of care indicators were used to measure care received for 137 women with a urinary incontinence diagnosis in a 120-physician hospital based multispecialty medical group. We also performed an abstraction of 146 patient records from primary care offices in Southern California. These charts were previously used as part of ACOVE (Assessing Care of Vulnerable Elders Project). As a post-hoc secondary analysis, the 2 populations were compared with respect to quality, as measured by compliance with the quality of care indicators. RESULTS: In the ACOVE population, 37.7% of patients with urinary incontinence underwent a pelvic examination vs 97.8% in the multispecialty medical group. Only 15.6% of cases in the multispecialty medical group and 14.2% in ACOVE (p = 0.86) had documentation that pelvic floor exercises were offered. Relatively few women with a body mass index of greater than 25 kg/m(2) were counseled about weight loss in either population (20.9% multispecialty medical group vs 26.1% ACOVE, p = 0.76). For women undergoing sling surgery, documentation of counseling about risks was lacking and only 9.3% of eligible cases (multispecialty medical group only) had documentation of the risks of mesh. CONCLUSIONS: Quality of care indicators are a feasible means to measure the care provided to women with urinary incontinence. Care varied by population studied and yet deficiencies in care were prevalent in both patient populations studied.


Assuntos
Gerenciamento Clínico , Terapia por Exercício/métodos , Atenção Primária à Saúde/normas , Indicadores de Qualidade em Assistência à Saúde , Qualidade da Assistência à Saúde , Incontinência Urinária/terapia , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto
12.
Genome Res ; 22(10): 1889-98, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22539651

RESUMO

The recognition potential of most families of DNA-binding domains (DBDs) remains relatively unexplored. Homeodomains (HDs), like many other families of DBDs, display limited diversity in their preferred recognition sequences. To explore the recognition potential of HDs, we utilized a bacterial selection system to isolate HD variants, from a randomized library, that are compatible with each of the 64 possible 3' triplet sites (i.e., TAANNN). The majority of these selections yielded sets of HDs with overrepresented residues at specific recognition positions, implying the selection of specific binders. The DNA-binding specificity of 151 representative HD variants was subsequently characterized, identifying HDs that preferentially recognize 44 of these target sites. Many of these variants contain novel combinations of specificity determinants that are uncommon or absent in extant HDs. These novel determinants, when grafted into different HD backbones, produce a corresponding alteration in specificity. This information was used to create more explicit HD recognition models, which can inform the prediction of transcriptional regulatory networks for extant HDs or the engineering of HDs with novel DNA-recognition potential. The diversity of recovered HD recognition sequences raises important questions about the fitness barrier that restricts the evolution of alternate recognition modalities in natural systems.


Assuntos
DNA/química , Proteínas de Homeodomínio/química , Animais , Sequência de Bases , Sítios de Ligação , DNA/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica
13.
Purinergic Signal ; 10(4): 603-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25129451

RESUMO

ATP is a gliotransmitter released from astrocytes. Extracellularly, ATP is metabolized by a series of enzymes, including ecto-5'-nucleotidase (eN; also known as CD73) which is encoded by the gene 5NTE and functions to form adenosine (ADO) from adenosine monophosphate (AMP). Under ischemic conditions, ADO levels in brain increase up to 100-fold. We used astrocytes cultured from 5NTE (+/+) or 5NTE (-/-) mice to evaluate the role of eN expressed by astrocytes in the production of ADO and inosine (INO) in response to glucose deprivation (GD) or oxygen-glucose deprivation (OGD). We also used co-cultures of these astrocytes with wild-type neurons to evaluate the role of eN expressed by astrocytes in the production of ADO and INO in response to GD, OGD, or N-methyl-D-aspartate (NMDA) treatment. As expected, astrocytes from 5NTE (+/+) mice produced adenosine from AMP; the eN inhibitor α,ß-methylene ADP (AOPCP) decreased ADO formation. In contrast, little ADO was formed by astrocytes from 5NTE (-/-) mice and AOPCP had no significant effect. GD and OGD treatment of 5NTE (+/+) astrocytes and 5NTE (+/+) astrocyte-neuron co-cultures produced extracellular ADO levels that were inhibited by AOPCP. In contrast, these conditions did not evoke ADO production in cultures containing 5NTE (-/-) astrocytes. NMDA treatment produced similar increases in ADO in both 5NTE (+/+) and 5NTE (-/-) astrocyte-neuron co-cultures; dipyridamole (DPR) but not AOPCP inhibited ADO production. These results indicate that eN is prominent in the formation of ADO from astrocytes but in astrocyte-neuron co-cultures, other enzymes or pathways contribute to rising ADO levels in ischemia-like conditions.


Assuntos
5'-Nucleotidase/metabolismo , Adenosina/biossíntese , Astrócitos/metabolismo , Inosina/biossíntese , Neurônios/metabolismo , Animais , Hipóxia Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Isquemia/metabolismo , Camundongos , Camundongos Knockout
14.
J Ultrasound Med ; 33(10): 1763-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25253822

RESUMO

OBJECTIVES: Traumatic brain injury (TBI) can cause adverse physiologic changes in fluid content within the brain, which may lead to changes in tissue elasticity (eg, stiffness). This study evaluated the ability of ultrasonic shear wave elastography to observe these changes in the brain after TBI in vivo. METHODS: Mice and rats received a mild TBI or sham surgery and were imaged acutely or 24 hours after injury using shear wave elastography, and the hemispheric stiffness values were compared. RESULTS: Stiffness values were consistent across brain hemispheres of sham TBI rodents. By 24 hours after TBI, relative brain tissue stiffness values for mice and rats each decreased ipsilaterally and increased contralaterally, both relative to each other and compared to sham TBI rodents (P < .05). The absolute tissue elasticity value increased for rats (P < .05) but not for mice. CONCLUSIONS: Differences between intrahemispheric stiffness values of rodent brains by 24 hours after mild TBI may reflect the observed edema and hemorrhage ipsilateral to TBI and the known reduction of cerebral blood flow in both brain hemispheres. If these hypotheses hold true, ultrasonic shear wave elastography may offer a method for detecting adverse changes in fluid content within the brain after mild TBI.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Animais , Artefatos , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Módulo de Elasticidade , Processamento de Imagem Assistida por Computador , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem
15.
Proc Natl Acad Sci U S A ; 108(22): 9060-5, 2011 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-21576502

RESUMO

The ribosomal incorporation of nonnative amino acids into polypeptides in living cells provides the opportunity to endow therapeutic proteins with unique pharmacological properties. We report here the first clinical study of a biosynthetic protein produced using an expanded genetic code. Incorporation of p-acetylphenylalanine (pAcF) at distinct locations in human growth hormone (hGH) allowed site-specific conjugation with polyethylene glycol (PEG) to produce homogeneous hGH variants. A mono-PEGylated mutant hGH modified at residue 35 demonstrated favorable pharmacodynamic properties in GH-deficient rats. Clinical studies in GH-deficient adults demonstrated efficacy and safety comparable to native human growth hormone therapy but with increased potency and reduced injection frequency. This example illustrates the utility of nonnative amino acids to optimize protein therapeutics in an analogous fashion to the use of medicinal chemistry to optimize conventional natural products, low molecular weight drugs, and peptides.


Assuntos
Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/farmacologia , Animais , Relação Dose-Resposta a Droga , Endocrinologia/métodos , Variação Genética , Humanos , Masculino , Mutação , Peptídeos/química , Fenilalanina/análogos & derivados , Fenilalanina/química , Polietilenoglicóis/química , Polímeros/química , Engenharia de Proteínas/métodos , Ratos , Ratos Sprague-Dawley , Ribossomos/química
16.
Hong Kong Med J ; 20(2): 152-5, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24714169

RESUMO

Pulmonary artery sarcoma is a rare disease with poor prognosis that has not been reported in Hong Kong. Its clinical and radiological presentation frequently mimics pulmonary embolism. Diagnosis is usually delayed until surgery, which is the treatment option that provides the best survival. Endobronchial ultrasound-guided transbronchial needle aspiration is an effective non-surgical technique for lymph node staging of lung cancer and diagnosis of mediastinal lesions via bronchoscopy. Here we discuss a case of pulmonary artery sarcoma diagnosed by this method, the second one in the literature, which serves to illustrate its potential use for early and minimally invasive diagnosis of the condition. Although such aspiration is a safe procedure, tissue sampling of extravascular extensions is advisable wherever possible.


Assuntos
Biópsia por Agulha Fina/métodos , Broncoscopia , Artéria Pulmonar/patologia , Sarcoma/patologia , Ultrassonografia de Intervenção , Neoplasias Vasculares/patologia , Idoso , Feminino , Humanos
17.
Acta Pharmacol Sin ; 34(1): 60-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23064722

RESUMO

Adenosine is a neuromodulator with its level increasing up to 100-fold during ischemic events, and attenuates the excitotoxic neuronal injury. Adenosine is produced both intracellularly and extracellularly, and nucleoside transport proteins transfer adenosine across plasma membranes. Adenosine levels and receptor-mediated effects of adenosine are regulated by intracellular ATP consumption, cellular release of ATP, metabolism of extracellular ATP (and other adenine nucleotides), adenosine influx, adenosine efflux and adenosine metabolism. Recent studies have used genetically modified mice to investigate the relative contributions of intra- and extracellular pathways for adenosine formation. The importance of cortical or hippocampal neurons as a source or a sink of adenosine under basal and hypoxic/ischemic conditions was addressed through the use of transgenic mice expressing human equilibrative nucleoside transporter 1 (hENT1) under the control of a promoter for neuron-specific enolase. From these studies, we conclude that ATP consumption within neurons is the primary source of adenosine in neuronal cultures, but not in hippocampal slices or in vivo mice exposed to ischemic conditions.


Assuntos
Adenosina/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Trifosfato de Adenosina/metabolismo , Animais , Encéfalo/irrigação sanguínea , Humanos , Neurônios/metabolismo , Neurônios/patologia , Proteínas de Transporte de Nucleosídeos/metabolismo
18.
J Ultrasound Med ; 32(3): 485-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23443189

RESUMO

OBJECTIVES: Ischemia, edema, elevated intracranial pressure, and reduced blood flow can occur in the brain as a result of ischemic stroke, including contralateral to the stroke via a process known as diaschisis. In this study, ultrasound elastography, an imaging process sensitive to the stiffness of tissue, including its relative fluid content, was used to study changes in the stiffness of individual cerebral hemispheres after transient ischemic injury. METHODS: Elastographic images of mouse brains were collected 24 and 72 hours after middle cerebral artery occlusion. The shear moduli of both ipsilateral and contralateral brain hemispheres for these mice were measured and compared to corresponding values of control animals. RESULTS: At 24 hours (but not 72 hours) after induction of ischemic stroke, there was a significant decrease in the shear modulus in the ipsilateral hemisphere (P < .01) and a significant increase in the shear modulus in the contralateral hemisphere compared to that of control animals (P < .01). Significant differences were also evident between ipsilateral and contralateral shear modulus values at 24 and 72 hours after infarction (P < .01 for both). CONCLUSIONS: The differences between intrahemispheric averages of shear moduli of the brains of animals with stroke at 24 and 72 hours after stroke induction likely reflect the initial formation of edema and reduction of cerebral blood flow known to develop ipsilateral to ischemic infarction, the known transient increase in intracranial pressure, as well as the known initial reduction of blood flow and subsequent development of edema in the contralateral hemisphere (diaschisis). Thus, elastography offers a possible method to detect subtle changes in brain after ischemic stroke.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/fisiopatologia , Encéfalo/fisiopatologia , Ecoencefalografia/métodos , Técnicas de Imagem por Elasticidade/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/fisiopatologia , Animais , Isquemia Encefálica/complicações , Módulo de Elasticidade , Medicina Baseada em Evidências , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Acidente Vascular Cerebral/complicações
19.
Transl Psychiatry ; 13(1): 293, 2023 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684229

RESUMO

Rumination is a maladaptive style of regulating thoughts and emotions. It is a common symptom of Major Depressive Disorder (MDD), and more severe rumination is associated with poorer medication and psychotherapy treatment outcomes, particularly among women. It is unclear to what extent rumination may influence the outcomes of, or be responsive to, repetitive Transcranial Magnetic Stimulation (rTMS) treatment of MDD. We retrospectively examined data collected during rTMS treatment of 155 patients (age 42.52 ± 14.22, 79 female) with moderately severe treatment-resistant MDD. The severity of rumination and depression was assessed before and during a course of 30 sessions of measurement-based rTMS treatment using the Ruminative Responses Scale (RSS) and the Patient Health Questionnaire (PHQ-9), respectively. Relationships among baseline levels of rumination, depression, and treatment outcome were assessed using a series of repeated measures linear mixed effects models. Both depression and rumination symptoms significantly improved after treatment, but improvement in depression was not a significant mediator of rumination improvement. Higher baseline rumination (but not depression severity) was associated with poorer depression outcomes independently of depression severity. Female gender was a significant predictor of worse outcomes for all RRS subscales. Both depressive and ruminative symptoms in MDD improved following rTMS treatment. These improvements were correlated, but improvement in rumination was not fully explained by reduction in depressive symptoms. These findings suggest that while improvement in rumination and depression severity during rTMS treatment are correlated, they are partly independent processes. Future studies should examine whether rumination symptoms should be specifically targeted with different rTMS treatment parameters.


Assuntos
Transtorno Depressivo Maior , Transtorno Depressivo Resistente a Tratamento , Feminino , Humanos , Estimulação Magnética Transcraniana , Transtorno Depressivo Maior/terapia , Estudos Retrospectivos , Transtorno Depressivo Resistente a Tratamento/terapia , Psicoterapia
20.
BMJ Paediatr Open ; 7(1)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37865398

RESUMO

OBJECTIVES: This qualitative descriptive study explores the experiences of family caregivers (FCs) of children with medical complexity who are initiated on new medical technology in the hospital and transition to new daily life at home. The study aims to investigate FCs' response and readiness for medical technology use, the value of education and transition support and the challenges associated with managing new medical technology in the home. STUDY DESIGN: A qualitative descriptive approach was used to conduct and analyse 14 semistructured interviews with a group of FCs composed of 11 mothers and 3 fathers. Content analysis was used to analyse transcripts of the caregiver interviews. The study was conducted at a tertiary paediatric hospital in Toronto, Canada. RESULTS: Our study revealed three main themes: FC's response and readiness for medical technology use, the value of education and transition support for initiation of new medical technology and the challenges associated with managing new medical technology in the home. FCs expressed emotional distress related to coping with the realisation that their child required medical technology. Although the theoretical and hands-on practice training instilled confidence in families, FCs reported feeling overwhelmed when they transitioned home with new medical technology. Finally, FCs reported significant psychological, emotional and financial challenges while caring for their technology-dependent child. CONCLUSIONS: Our study reveals the unique challenges faced by FCs who care for technology-dependent children. These findings highlight the need to implement a comprehensive education and transition programme that provides longitudinal support for all aspects of care.


Assuntos
Adaptação Psicológica , Cuidadores , Feminino , Humanos , Criança , Cuidadores/psicologia , Estresse Psicológico/psicologia , Mães , Tecnologia
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