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1.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38100360

RESUMO

Studies on the neural bases of sentence production have yielded mixed results, partly due to differences in tasks and participant types. In this study, 101 individuals with primary progressive aphasia (PPA) were evaluated using a test that required spoken production following an auditory prime (Northwestern Assessment of Verbs and Sentences-Sentence Production Priming Test, NAVS-SPPT), and one that required building a sentence by ordering word cards (Northwestern Anagram Test, NAT). Voxel-Based Morphometry revealed that gray matter (GM) volume in left inferior/middle frontal gyri (L IFG/MFG) was associated with sentence production accuracy on both tasks, more so for complex sentences, whereas, GM volume in left posterior temporal regions was exclusively associated with NAVS-SPPT performance and predicted by performance on a Digit Span Forward (DSF) task. Verb retrieval deficits partly mediated the relationship between L IFG/MFG and performance on the NAVS-SPPT. These findings underscore the importance of L IFG/MFG for sentence production and suggest that this relationship is partly accounted for by verb retrieval deficits, but not phonological loop integrity. In contrast, it is possible that the posterior temporal cortex is associated with auditory short-term memory ability, to the extent that DSF performance is a valid measure of this in aphasia.


Assuntos
Afasia Primária Progressiva , Afasia , Humanos , Idioma , Linguística , Vocabulário , Afasia Primária Progressiva/diagnóstico por imagem
2.
Proc Natl Acad Sci U S A ; 119(26): e2116738119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35749366

RESUMO

Tumor infiltration by T cells profoundly affects cancer progression and responses to immunotherapy. However, the tumor immunosuppressive microenvironment can impair the induction, trafficking, and local activity of antitumor T cells. Here, we investigated whether intratumoral injection of virus-derived peptide epitopes could activate preexisting antiviral T cell responses locally and promote antitumor responses or antigen spreading. We focused on a mouse model of cytomegalovirus (CMV), a highly prevalent human infection that induces vigorous and durable T cell responses. Mice persistently infected with murine CMV (MCMV) were challenged with lung (TC-1), colon (MC-38), or melanoma (B16-F10) tumor cells. Intratumoral injection of MCMV-derived T cell epitopes triggered in situ and systemic expansion of their cognate, MCMV-specific CD4+ or CD8+ T cells. The MCMV CD8+ T cell epitopes injected alone provoked arrest of tumor growth and some durable remissions. Intratumoral injection of MCMV CD4+ T cell epitopes with polyinosinic acid:polycytidylic acid (pI:C) preferentially elicited tumor antigen-specific CD8+ T cells, promoted tumor clearance, and conferred long-term protection against tumor rechallenge. Notably, secondary proliferation of MCMV-specific CD8+ T cells correlated with better tumor control. Importantly, intratumoral injection of MCMV-derived CD8+ T cell-peptide epitopes alone or CD4+ T cell-peptide epitopes with pI:C induced potent adaptive and innate immune activation of the tumor microenvironment. Thus, CMV-derived peptide epitopes, delivered intratumorally, act as cytotoxic and immunotherapeutic agents to promote immediate tumor control and long-term antitumor immunity that could be used as a stand-alone therapy. The tumor antigen-agnostic nature of this approach makes it applicable across a broad range of solid tumors regardless of their origin.


Assuntos
Linfócitos T CD8-Positivos , Infecções por Citomegalovirus , Citomegalovirus , Epitopos de Linfócito T , Neoplasias , Animais , Antígenos de Neoplasias/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Citomegalovirus/imunologia , Infecções por Citomegalovirus/imunologia , Epitopos de Linfócito T/administração & dosagem , Epitopos de Linfócito T/imunologia , Imunoterapia , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Poli I-C/administração & dosagem , Poli I-C/imunologia , Microambiente Tumoral
3.
J Sleep Res ; : e14261, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38859728

RESUMO

Patients with idiopathic hypersomnia frequently report having unrefreshing naps. However, whether they have abnormal sleep architecture during naps that may explain their unrefreshing aspect is unknown. We compared sleep architecture during short daytime naps in patients with idiopathic hypersomnia reporting unrefreshing and refreshing naps. One-hundred and thirty-four patients tested with one-night polysomnography, followed by an adapted version of the Multiple Sleep Latency Test with four naps, were included. They were asked about the refreshing aspect of their habitual naps during a clinical interview. They were classified as having objective (Multiple Sleep Latency Test ≤ 8 min) or subjective idiopathic hypersomnia (Multiple Sleep Latency Test > 8 min), and as presenting refreshing or unrefreshing naps. We tested Group differences (refreshing versus unrefreshing naps) on nap sleep architecture in the whole sample and for subjective and objective idiopathic hypersomnia subgroups separately using ANCOVAs. No Group effects were observed in the Multiple Sleep Latency Test architecture in the whole sample and in objective and subjective idiopathic hypersomnia subgroups. This study provides preliminary evidence that reporting unrefreshing naps is not associated with clinically significant findings in Multiple Sleep Latency Test sleep architecture in patients with idiopathic hypersomnia. Given that naps taken by patients with idiopathic hypersomnia are typically long, future studies should investigate longer daytime sleep episodes.

4.
J Sleep Res ; 33(1): e13938, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37309703

RESUMO

Research on the relationship between obstructive sleep apnea and cognitive functioning has yielded conflicting results, particularly in the older population, and moderators of this association have rarely been studied. Here we investigated the cross-sectional association between obstructive sleep apnea and cognitive functioning as well as the moderating effect of age, sex, apolipoprotein E4, and obesity on this association among community-dwelling older people. We analysed data from 496 participants (71.4 ± 4.4 years; 45.6% men) of the HypnoLaus study who underwent polysomnography and a battery of neuropsychological tests. The sample was categorised as no-to-mild obstructive sleep apnea (apnea-hypopnea index 0-14.9/h; reference), moderate obstructive sleep apnea (apnea-hypopnea index 15.0-29.9/h), or severe obstructive sleep apnea (apnea-hypopnea index ≥30/h). Regression and moderation analyses were performed with adjustment for confounders. Apolipoprotein E4 and obesity moderated the association between severe obstructive sleep apnea and processing speed, whereas no moderating effects were found for age and sex. In apolipoprotein E4 carriers only, severe obstructive sleep apnea was associated with lower performance in Stroop condition 1 (B = 3.13, p = 0.024). In obese participants only, severe obstructive sleep apnea was associated with lower performance in Stroop condition 1 (B = 3.02, p = 0.025) and Stroop condition 2 (B = 3.30, p = 0.034). Severe obstructive sleep apnea was also associated with lower executive function in the whole sample according to Stroop condition 3 (B = 3.44, p = 0.020) and Stroop interference score (B = 0.24, p = 0.006). Our findings support associations of severe obstructive sleep apnea (but not moderate obstructive sleep apnea) with lower performance in processing speed and executive function in the older general population. Apolipoprotein E4 and obesity appear to be vulnerability factors that strengthen the association between severe obstructive sleep apnea and lower performance in processing speed.


Assuntos
Apolipoproteína E4 , Apneia Obstrutiva do Sono , Masculino , Humanos , Idoso , Feminino , Apolipoproteína E4/genética , Estudos Transversais , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia , Cognição , Obesidade/complicações , Obesidade/epidemiologia
5.
Am J Primatol ; 86(6): e23614, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38433290

RESUMO

Primates face severe challenges from climate change, with warming expected to increase animals' thermoregulatory demands. Primates have limited long-term options to cope with climate change, but possess a remarkable capacity for behavioral plasticity. This creates an urgency to better understand the behavioral mechanisms primates use to thermoregulate. While considerable information exists on primate behavioral thermoregulation, it is often scattered in the literature in a manner that is difficult to integrate. This review evaluates the status of the available literature on primate behavioral thermoregulation to facilitate future research. We surveyed peer-reviewed publications on primate thermoregulation for N = 17 behaviors across four thermoregulatory categories: activity budgeting, microhabitat use, body positioning, and evaporative cooling. We recorded data on the primate taxa evaluated, support for a thermoregulatory function, thermal variable assessed, and naturalistic/manipulative study conditions. Behavioral thermoregulation was pervasive across primates, with N = 721 cases of thermoregulatory behaviors identified across N = 284 published studies. Most genera were known to utilize multiple behaviors ( x ¯ = 4.5 ± 3.1 behaviors/genera). Activity budgeting behaviors were the most commonly encountered category in the literature (54.5% of cases), while evaporative cooling behaviors were the least represented (6.9% of cases). Behavioral thermoregulation studies were underrepresented for certain taxonomic groups, including lemurs, lorises, galagos, and Central/South American primates, and there were large within-taxa disparities in representation of genera. Support for a thermoregulatory function was consistently high across all behaviors, spanning both hot- and cold-avoidance strategies. This review reveals asymmetries in the current literature and avenues for future research. Increased knowledge of the impact thermoregulatory behaviors have on biologically relevant outcomes is needed to better assess primate responses to warming environments and develop early indicators of thermal stress.


Assuntos
Comportamento Animal , Regulação da Temperatura Corporal , Mudança Climática , Primatas , Animais , Regulação da Temperatura Corporal/fisiologia , Primatas/fisiologia , Comportamento Animal/fisiologia
6.
J Neurolinguistics ; 692024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37994312

RESUMO

Adjectives (e.g., hungry) are an important part of language, but have been little studied in individuals with impaired language. Adjectives are used in two different ways in English: attributively, to modify a noun (the hungry dog); or predicatively, after a verb (the dog is hungry). Attributive adjectives have a more complex grammatical structure than predicative adjectives, and may therefore be particularly prone to disruption in individuals with grammatical impairments. We investigated adjective production in three subtypes of primary progressive aphasia (PPA: agrammatic, semantic, logopenic), as well as in agrammatic stroke aphasia and a group of healthy control participants. Participants produced narratives based on picture books, and we coded every adjective they produced for its syntactic structure. Compared to healthy controls, the two agrammatic groups, but not the other two patient groups, produced significantly fewer attributive adjectives per sentence. All four patient groups were similar to controls for their rate of predicative adjective production. In addition, we found a significant correlation in the agrammatic PPA participants between their rate of producing attributive adjective and impaired production of sentences with complex syntactic structure (subject cleft sentences like It was the boy that chased the girl); no such correlation was found for predicative adjectives. Irrespective of structure, we examined the lexical characteristics of the adjectives that were produced, including length, frequency, semantic diversity and neighborhood density. Overall, the lexical characteristics of the produced adjectives were largely consistent with the language profile of each group. In sum, the results suggest that attributive adjectives present a particular challenge for individuals with agrammatic language production, and add a new dimension to the description of agrammatism. Our results further suggest that attributive adjectives may be a fruitful target for improved treatment and recovery of agrammatic language.

7.
Alzheimers Dement ; 20(6): 4092-4105, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38716833

RESUMO

INTRODUCTION: The limbic system is critical for memory function and degenerates early in the Alzheimer's disease continuum. Whether obstructive sleep apnea (OSA) is associated with alterations in the limbic white matter tracts remains understudied. METHODS: Polysomnography, neurocognitive assessment, and brain magnetic resonance imaging (MRI) were performed in 126 individuals aged 55-86 years, including 70 cognitively unimpaired participants and 56 participants with mild cognitive impairment (MCI). OSA measures of interest were the apnea-hypopnea index and composite variables of sleep fragmentation and hypoxemia. Microstructural properties of the cingulum, fornix, and uncinate fasciculus were estimated using free water-corrected diffusion tensor imaging. RESULTS: Higher levels of OSA-related hypoxemia were associated with higher left fornix diffusivities only in participants with MCI. Microstructure of the other white matter tracts was not associated with OSA measures. Higher left fornix diffusivities correlated with poorer episodic verbal memory. DISCUSSION: OSA may contribute to fornix damage and memory dysfunction in MCI. HIGHLIGHTS: Sleep apnea-related hypoxemia was associated with altered fornix integrity in MCI. Altered fornix integrity correlated with poorer memory function. Sleep apnea may contribute to fornix damage and memory dysfunction in MCI.


Assuntos
Disfunção Cognitiva , Imagem de Tensor de Difusão , Fórnice , Hipóxia , Humanos , Masculino , Feminino , Disfunção Cognitiva/etiologia , Idoso , Fórnice/diagnóstico por imagem , Fórnice/patologia , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Hipóxia/complicações , Polissonografia , Testes Neuropsicológicos/estatística & dados numéricos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Imageamento por Ressonância Magnética , Síndromes da Apneia do Sono/complicações , Apneia Obstrutiva do Sono/complicações
8.
J Virol ; 96(7): e0185721, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35285688

RESUMO

Human papillomaviruses (HPVs) are nonenveloped double-stranded DNA viruses that utilize heparan sulfate proteoglycans (HSPGs) as initial attachment factors prior to cell entry and infection. While extensively characterized, the selective interaction between HPV and HSPGs is generally studied using standard in vitro conditions, which fail to account for the effects that media additives, such as fetal bovine serum (FBS), can have on viral binding. As environmental conditions and growth factors associated with wound healing are thought to play a role in natural HPV infection, we sought to investigate the effects that serum or platelet extracts could have on the binding and infectivity of HPV. Here, we demonstrate that high concentrations of FBS and human serum greatly inhibit HPV16 binding, and that for FBS, this effect results from the obstruction of cell surface HSPGs by serum-derived heparin-binding proteins (HBPs). Surprisingly, we found that under these conditions, HPV particles utilize 6O-sulfated chondroitin sulfate proteoglycans (CSPGs) as initial binding receptors prior to infection. These findings were corroborated by small interfering RNA (siRNA)-mediated knockdown experiments, as well as through a cancer cell line screen, where we identified a strong association between viral binding in high serum and the expression of chondroitin sulfate biosynthesis genes. Furthermore, HPV binding in the presence of human platelet lysate also demonstrated an increased dependance on CSPGs, suggesting a possible role for these receptor proteoglycans in active wound healing environments. Overall, this work highlights the significant influence that serum/platelet factors can have on virus binding and identifies CSPGs as alternative cell attachment receptors for HPV. IMPORTANCE Heparan sulfate proteoglycans (HSPGs) have previously been identified as primary attachment factors for the initial binding of human papillomaviruses (HPVs) prior to infection. Here, we demonstrate that in vitro, HPV binding to HSPGs is strongly dependent on the surrounding experimental conditions, including the concentration of fetal bovine serum (FBS). We found that high concentrations of FBS can block HSPG-binding sites and cause a dependence on 6O-sulfated chondroitin sulfate proteoglycans (CSPGs) as alternative initial viral receptors. Further, we demonstrate that use of a human-derived alternative to FBS, human platelet lysate, also occludes HSPG-dependent binding, causing a shift toward CSPGs for viral attachment. As HPV infection of basal epithelial cells is thought to occur at sites of microtrauma with exposure to high serum levels and platelet factors, these unexpected findings highlight a possible role for CSPGs as important cellular receptors for the binding and infectivity of HPV in vivo.


Assuntos
Proteoglicanas de Sulfatos de Condroitina , Papillomavirus Humano 16 , Infecções por Papillomavirus , Linhagem Celular Tumoral , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Papillomavirus Humano 16/efeitos dos fármacos , Papillomavirus Humano 16/metabolismo , Humanos , Ligação Proteica , Soroalbumina Bovina/farmacologia
9.
Brain ; 145(6): 2133-2148, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35441216

RESUMO

Primary progressive aphasia is a neurodegenerative disease that selectively impairs language without equivalent impairment of speech, memory or comportment. In 118 consecutive autopsies on patients with primary progressive aphasia, primary diagnosis was Alzheimer's disease neuropathological changes (ADNC) in 42%, corticobasal degeneration or progressive supranuclear palsy neuropathology in 24%, Pick's disease neuropathology in 10%, transactive response DNA binding proteinopathy type A [TDP(A)] in 10%, TDP(C) in 11% and infrequent entities in 3%. Survival was longest in TDP(C) (13.2 ± 2.6 years) and shortest in TDP(A) (7.1 ± 2.4 years). A subset of 68 right-handed participants entered longitudinal investigations. They were classified as logopenic, agrammatic/non-fluent or semantic by quantitative algorithms. Each variant had a preferred but not invariant neuropathological correlate. Seventy-seven per cent of logopenics had ADNC, 56% of agrammatics had corticobasal degeneration/progressive supranuclear palsy or Pick's disease and 89% of semantics had TDP(C). Word comprehension impairments had strong predictive power for determining underlying neuropathology positively for TDP(C) and negatively for ADNC. Cortical atrophy was smallest in corticobasal degeneration/progressive supranuclear palsy and largest in TDP(A). Atrophy encompassed posterior frontal but not temporoparietal cortex in corticobasal degeneration/progressive supranuclear palsy, anterior temporal but not frontoparietal cortex in TDP(C), temporofrontal but not parietal cortex in Pick's disease and all three lobes with ADNC or TDP(A). There were individual deviations from these group patterns, accounting for less frequent clinicopathologic associations. The one common denominator was progressive asymmetric atrophy overwhelmingly favouring the left hemisphere language network. Comparisons of ADNC in typical amnestic versus atypical aphasic dementia and of TDP in type A versus type C revealed fundamental biological and clinical differences, suggesting that members of each pair may constitute distinct clinicopathologic entities despite identical downstream proteinopathies. Individual TDP(C) participants with unilateral left temporal atrophy displayed word comprehension impairments without additional object recognition deficits, helping to dissociate semantic primary progressive aphasia from semantic dementia. When common and uncommon associations were considered in the set of 68 participants, one neuropathology was found to cause multiple clinical subtypes, and one subtype of primary progressive aphasia to be caused by multiple neuropathologies, but with different probabilities. Occasionally, expected clinical manifestations of atrophy sites were absent, probably reflecting individual peculiarities of language organization. The hemispheric asymmetry of neurodegeneration and resultant language impairment in primary progressive aphasia reflect complex interactions among the cellular affinities of the degenerative disease, the constitutive biology of language cortex, familial or developmental vulnerabilities of this network and potential idiosyncrasies of functional anatomy in the affected individual.


Assuntos
Doença de Alzheimer , Afasia Primária Progressiva , Doenças Neurodegenerativas , Doença de Pick , Paralisia Supranuclear Progressiva , Doença de Alzheimer/patologia , Atrofia/patologia , Encéfalo/patologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Doenças Neurodegenerativas/patologia , Doença de Pick/patologia , Paralisia Supranuclear Progressiva/patologia
10.
BMC Public Health ; 23(1): 2389, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38041070

RESUMO

BACKGROUND: Food pantry clients have high rates of food insecurity and greater risk for and prevalence of diet-related diseases. Many clients face time, resource, and physical constraints that limit their ability to prepare healthy meals using foods typically provided by pantries. We compared two novel approaches to alleviate those barriers and encourage healthier eating: meal kits, which bundle ingredients with a recipe on how to prepare a healthy meal, and nutritious no-prep meals, which can be eaten after thawing or microwaving. METHODS: Participants were adult pantry clients from a large food pantry in the Southern sector of Dallas, Texas. We conducted a repeated measures between-subjects study with 70 clients randomized to receive 14-days of meal kits (n = 35) or no-prep meals (n = 35). Participants completed questionnaires at baseline and two-week follow-up on demographics, hedonic liking of study meals, perceived dietary quality, and food security. Two-way repeated measures analysis of variance was used to examine group and time effects, and group by time interactions. We also describe feasibility and satisfaction outcomes to inform future implementation. RESULTS: Sixty-six participants completed the study (94%). Participants were predominantly Hispanic or Latino(a) (63%) and African American or Black (31%) women (90%). There was a significant interaction on hedonic liking of study meals (ηp²=0.16, F(1,64) = 11.78, p < .001), such that participants that received meal kits had greater improvements in hedonic liking over time than participants in the no-prep group. We observed significant improvements in perceived dietary quality (ηp²=0.36, F(1,64) = 36.38, p < .001) and food security (ηp²=0.36, F(1,64) = 36.38, p < .001) across both groups over time, but no between group differences or significant interactions indicating one intervention was more effective than the other. Program satisfaction was high across both groups, but higher among the meal kit group (ηp²=0.09, F(1,64) = 6.28, p = .015). CONCLUSIONS: Results suggest nutritious meal kits and no-prep meals may be desirable nutrition intervention strategies for pantry clients and have potential to increase food security and perceived dietary quality in the short-term. Our findings are limited by a small sample and short follow-up. Future studies should continue to test both interventions, and include longer follow-up, objective measures of dietary quality, and relevant clinical outcomes. TRIAL REGISTRATION: This trial was registered on 25/10/2022 on ClinicalTrials.gov, identifier: NCT05593510.


Assuntos
Assistência Alimentar , Abastecimento de Alimentos , Adulto , Humanos , Feminino , Masculino , Projetos Piloto , Dieta , Refeições , Segurança Alimentar
11.
Stroke ; 53(5): 1606-1614, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35078348

RESUMO

BACKGROUND: Poststroke recovery depends on multiple factors and varies greatly across individuals. Using machine learning models, this study investigated the independent and complementary prognostic role of different patient-related factors in predicting response to language rehabilitation after a stroke. METHODS: Fifty-five individuals with chronic poststroke aphasia underwent a battery of standardized assessments and structural and functional magnetic resonance imaging scans, and received 12 weeks of language treatment. Support vector machine and random forest models were constructed to predict responsiveness to treatment using pretreatment behavioral, demographic, and structural and functional neuroimaging data. RESULTS: The best prediction performance was achieved by a support vector machine model trained on aphasia severity, demographics, measures of anatomic integrity and resting-state functional connectivity (F1=0.94). This model resulted in a significantly superior prediction performance compared with support vector machine models trained on all feature sets (F1=0.82, P<0.001) or a single feature set (F1 range=0.68-0.84, P<0.001). Across random forest models, training on resting-state functional magnetic resonance imaging connectivity data yielded the best F1 score (F1=0.87). CONCLUSIONS: While behavioral, multimodal neuroimaging data and demographic information carry complementary information in predicting response to rehabilitation in chronic poststroke aphasia, functional connectivity of the brain at rest after stroke is a particularly important predictor of responsiveness to treatment, both alone and combined with other patient-related factors.


Assuntos
Afasia , Acidente Vascular Cerebral , Afasia/diagnóstico por imagem , Afasia/etiologia , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Acidente Vascular Cerebral/complicações
12.
J Neurolinguistics ; 622022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35002061

RESUMO

Language and music rely on complex sequences organized according to syntactic principles that are implicitly understood by enculturated listeners. Across both domains, syntactic processing involves predicting and integrating incoming elements into higher-order structures. According to the Shared Syntactic Integration Resource Hypothesis (SSIRH; Patel, 2003), musical and linguistic syntactic processing rely on shared resources for integrating incoming elements (e.g., chords, words) into unfolding sequences. One prediction of the SSIRH is that people with agrammatic aphasia (whose deficits are due to syntactic integration problems) should present with deficits in processing musical syntax. We report the first neural study to test this prediction: event-related potentials (ERPs) were measured in response to musical and linguistic syntactic violations in a group of people with agrammatic aphasia (n=7) compared to a group of healthy controls (n=14) using an acceptability judgement task. The groups were matched with respect to age, education, and extent of musical training. Violations were based on morpho-syntactic relations in sentences and harmonic relations in chord sequences. Both groups presented with a significant P600 response to syntactic violations across both domains. The aphasic participants presented with a reduced-amplitude posterior P600 compared to the healthy adults in response to linguistic, but not musical, violations. Participants with aphasia did however present with larger frontal positivities in response to violations in both domains. Intriguingly, extent of musical training was associated with larger posterior P600 responses to syntactic violations of language and music in both groups. Overall, these findings are not consistent with the predictions of the SSIRH, and instead suggest that linguistic, but not musical, syntactic processing may be selectively impaired in stroke-induced agrammatic aphasia. However, the findings also suggest a relationship between musical training and linguistic syntactic processing, which may have clinical implications for people with aphasia, and motivates more research on the relationship between these two domains.

13.
Neuroimage ; 224: 117374, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949711

RESUMO

Functional neuroimaging and lesion-symptom mapping investigations implicate a left frontal-temporal-parietal network for sentence processing. The majority of studies have focused on sentence comprehension, with fewer in the domain of sentence production, which have not fully elucidated overlapping and/or unique brain structures associated with the two domains, particularly for sentences with noncanonical word order. Using voxel-based lesion symptom mapping (VLSM) we examined the relationship between lesions within the left hemisphere language network and both sentence comprehension and production of simple and complex syntactic structures in 76 participants with chronic stroke-induced aphasia. Results revealed shared regions across domains in the anterior and posterior superior temporal gyri (aSTG, pSTG), and the temporal pole (adjusted for verb production/comprehension). Additionally, comprehension was associated with lesions in the anterior and posterior middle temporal gyri (aMTG, pMTG), the MTG temporooccipital regions, SMG/AG, central and parietal operculum, and the insula. Subsequent VLSM analyses (production versus comprehension) revealed critical regions associated with each domain: anterior temporal lesions were associated with production; posterior temporo-parietal lesions were associated with comprehension, implicating important roles for regions within the ventral and dorsal stream processing routes, respectively. Processing of syntactically complex, noncanonical (adjusted for canonical), sentences was associated with damage to the pSTG across domains, with additional damage to the pMTG and IPL associated with impaired sentence comprehension, suggesting that the pSTG is crucial for computing noncanonical sentences across domains and that the pMTG, and IPL are necessary for re-analysis of thematic roles as required for resolution of long-distance dependencies. These findings converge with previous studies and extend our knowledge of the neural mechanisms of sentence comprehension to production, highlighting critical regions associated with both domains, and further address the mechanism engaged for syntactic computation, controlled for the contribution of verb processing.


Assuntos
Afasia/fisiopatologia , Compreensão/fisiologia , Lobo Frontal/fisiopatologia , Lobo Temporal/fisiopatologia , Mapeamento Encefálico/métodos , Neuroimagem Funcional/métodos , Humanos , Idioma , Imageamento por Ressonância Magnética/métodos , Masculino , Lobo Parietal/fisiopatologia
14.
Curr Neurol Neurosci Rep ; 21(3): 11, 2021 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-33586028

RESUMO

PURPOSE OF REVIEW: Obstructive sleep apnea is extremely prevalent in the elderly and may precipitate dementia. We review recent advances on gray and white matter structure in obstructive sleep apnea, the impact of treatment, and potential pathological and neurodegenerative processes underlying brain structural changes. RECENT FINDINGS: Two opposite patterns are observed in neuroimaging studies of obstructive sleep apnea. One may indicate cellular damage (gray matter atrophy, higher white matter hyperintensity burden, lower white matter fractional anisotropy, higher water diffusivities), while the other (gray matter hypertrophy, restricted white matter diffusivities) may reflect transitory responses, such as intracellular edema, reactive gliosis or compensatory structural changes. Treating obstructive sleep apnea could partly reverse these structural changes. Structural alterations related to obstructive sleep apnea may follow a multi-determined biphasic pattern depending on numerous factors (e.g. severity, symptomatology, age) that could tip the scale toward neurodegeneration and need to be investigated by longitudinal studies.


Assuntos
Apneia Obstrutiva do Sono , Substância Branca , Idoso , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Apneia Obstrutiva do Sono/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
15.
J Immunol ; 202(4): 1250-1264, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30635393

RESUMO

Recent insight into the mechanisms of induction of tissue-resident memory (TRM) CD8+ T cells (CD8+ TRM) enables the development of novel vaccine strategies against sexually transmitted infections. To maximize both systemic and genital intraepithelial CD8+ T cells against vaccine Ags, we assessed combinations of i.m. and intravaginal routes in heterologous prime-boost immunization regimens with unrelated viral vectors. Only i.m. prime followed by intravaginal boost induced concomitant strong systemic and intraepithelial genital-resident CD8+ T cell responses. Intravaginal boost with vectors expressing vaccine Ags was far superior to intravaginal instillation of CXCR3 chemokine receptor ligands or TLR 3, 7, and 9 agonists to recruit and increase the pool of cervicovaginal CD8+ TRM Transient Ag presentation increased trafficking of cognate and bystander circulating activated, but not naive, CD8+ T cells into the genital tract and induced in situ proliferation and differentiation of cognate CD8+ TRM Secondary genital CD8+ TRM were induced in the absence of CD4+ T cell help and shared a similar TCR repertoire with systemic CD8+ T cells. This prime-pull-amplify approach elicited systemic and genital CD8+ T cell responses against high-risk human papillomavirus type 16 E7 oncoprotein and conferred CD8-mediated protection to a vaccinia virus genital challenge. These results underscore the importance of the delivery route of nonreplicating vectors in prime-boost immunization to shape the tissue distribution of CD8+ T cell responses. In this context, the importance of local Ag presentation to elicit genital CD8+ TRM provides a rationale to develop novel vaccines against sexually transmitted infections and to treat human papillomavirus neoplasia.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Papillomavirus Humano 16/imunologia , Vacinas contra Papillomavirus/imunologia , Animais , Células HEK293 , Humanos , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C57BL , Vacinas contra Papillomavirus/genética , Vacinação
16.
Neurocase ; 27(1): 39-56, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33378229

RESUMO

This study reports the results of a longitudinal study examining the effects of treatment for sentence processing deficits for a 70-year-old gentleman (DK) with the agrammatic variant of Primary Progressive Aphasia (PPA). On entry into the study, he presented with a 2-year history of impaired verb and sentence processing and concomitant neural atrophy in primarily subcortical regions. Spanning an 18-month period, treatment focused on improving comprehension and production of syntactically complex, passive and object cleft, structures, consecutively. Results, derived from extensive behavioral and neurocognitive testing, showed not only improved ability to comprehend and produce both trained and untrained, less complex, linguistically related structures in offline tasks, but also improved online sentence processing strategies as revealed by partially normalized eye movements in online comprehension (i.e., emergence of thematic prediction and thematic integration) and production (i.e., use of incremental processing) tasks. Changes in neural activation from pre- to post-treatment of both structures also were found, with upregulation of tissue in both the left and right hemispheres, overlapping with regions recruited by neurotypical adults performing the same task. These findings indicate that Treatment of Underlying Forms (TUF) is effective for treatment of patients with the agrammatic variant of PPA (as it is for those with stroke-induced agrammatism), and show that unaffected neural tissue in patients with PPA is malleable and may be recruited to support language, providing evidence of experience-based plasticity in neurodegenerative disease.


Assuntos
Afasia Primária Progressiva , Doenças Neurodegenerativas , Adulto , Idoso , Afasia de Broca , Humanos , Idioma , Estudos Longitudinais , Masculino
17.
Adv Exp Med Biol ; 1281: 33-49, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33433867

RESUMO

Primary progressive aphasia (PPA) is a dementia syndrome associated with several neuropathologic entities, including Alzheimer's disease (AD) and all major forms of frontotemporal lobar degeneration (FTLD). It is classified into subtypes defined by the nature of the language domain that is most impaired. The asymmetric neurodegeneration of the hemisphere dominant for language (usually left) is one consistent feature of all PPA variants. This feature offers unique opportunities for exploring mechanisms of selective vulnerability in neurodegenerative diseases and the neuroanatomy of language. This chapter reviews some of the current trends in PPA research as well as the challenges that remain to be addressed on the nosology, clinicopathologic correlations, and therapy of this syndrome.


Assuntos
Doença de Alzheimer , Afasia Primária Progressiva , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Humanos , Idioma
18.
Eur J Neurosci ; 52(8): 3963-3978, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32282965

RESUMO

Investigating the neurobiology of language impairment and treatment in chronic stroke aphasia using fMRI requires an understanding of measurement variability within and between participants. In this multicenter study, we evaluated the scan-rescan reliability of an auditory and visual (written) story comprehension paradigm in stroke participants with aphasia (N = 65) and healthy controls (N = 22). The multi-modal task was conducted twice (~1 week apart) on separate visits upon study enrolment and twice again at completion three months later. A non-language visuomotor task was studied in the aphasia group only, which was conducted once per time point (3 months apart). While participants were asked to make responses during the comprehension task, these in-scanner responses were not recorded. Reliability was assessed using intraclass correlation coefficient (ICC) at both group and individual participant levels. The visual story comprehension condition had higher reliability than the auditory condition in both groups, with participants with aphasia exhibiting lower reliability than controls in both conditions (stroke ICC = .43, healthy ICC = .81). Differences in reliability within the group of participants with aphasia were found to be partially explained by overall language impairment as well as greater head motion. In the participants with aphasia, the visuomotor paradigm was found to have greater reliability than the story comprehension task at equivalent interscan intervals (visuomotor = 0.50, comprehension = 0.34), and its reliability was not associated with language impairment. This work highlights the importance of considering the reliability of fMRI tasks in aphasia research, provides strategies to improve reliability and has potential implications for the field of clinical neuroimaging in general.


Assuntos
Afasia , Acidente Vascular Cerebral , Afasia/diagnóstico por imagem , Afasia/etiologia , Humanos , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
19.
J Virol ; 93(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31092566

RESUMO

Infectious human papillomavirus 16 (HPV16) L1/L2 pseudovirions were found to remain largely intact during vesicular transport to the nucleus. By electron microscopy, capsids with a diameter of 50 nm were clearly visible within small vesicles attached to mitotic chromosomes and to a lesser extent within interphase nuclei, implying nuclear disassembly. By confocal analysis, it was determined that nuclear entry of assembled L1 is dependent upon the presence of the minor capsid protein, L2, but independent of encapsidated DNA. We also demonstrate that L1 nuclear localization and mitotic chromosome association can occur in vivo in the murine cervicovaginal challenge model of HPV16 infection. These findings challenge the prevailing concepts of PV uncoating and disassembly. More generally, they document that a largely intact viral capsid can enter the nucleus within a transport vesicle, establishing a novel mechanism by which a virus accesses the nuclear cellular machinery.IMPORTANCE Papillomaviruses (PVs) comprise a large family of nonenveloped DNA viruses that include HPV16, among other oncogenic types, the causative agents of cervical cancer. Delivery of the viral DNA into the host cell nucleus is necessary for establishment of infection. This was thought to occur via a subviral complex following uncoating of the larger viral capsid. In this study, we demonstrate that little disassembly of the PV capsid occurs prior to nuclear delivery. These surprising data reveal a previously unrecognized viral strategy to access the nuclear replication machinery. Understanding viral entry mechanisms not only increases our appreciation of basic cell biological pathways but also may lead to more effective antiviral interventions.


Assuntos
Proteínas do Capsídeo/metabolismo , Núcleo Celular/virologia , Papillomavirus Humano 16/fisiologia , Proteínas Oncogênicas Virais/metabolismo , Internalização do Vírus , Animais , Capsídeo/metabolismo , Capsídeo/ultraestrutura , Linhagem Celular , Modelos Animais de Doenças , Papillomavirus Humano 16/ultraestrutura , Humanos , Microscopia Eletrônica , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia
20.
Spinal Cord ; 58(1): 43-52, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31462758

RESUMO

STUDY DESIGN: Prospective cohort study. OBJECTIVES: To determine the extent of functional recovery between 6 and 12 months following a traumatic spinal cord injury (TSCI) and to identify individuals achieving a small clinical functional improvement during this period. SETTING: A single level-1 trauma center specialized in SCI care. METHODS: A cohort of 125 patients sustaining TSCI was studied. The Spinal Cord Independence Measure (SCIM) version III at 6 and 12 months post injury was used as the main outcome measure. RESULTS: The observed functional improvement for the final cohort did not reach a clinically significant level between 6 and 12 months post injury. However, 30.4% of individuals achieved this level (≥4 points in the SCIM-III total score). This group showed a higher proportion of motor-complete TSCI (AIS grade A or B) and showed a tendency toward older age and higher trauma severity. Longer duration of intensive functional rehabilitation was the single factor associated with reaching a small clinically important improvement in the SCIM-III total score. CONCLUSIONS: Functional status between 6 and 12 months following a TSCI may be considered clinically similar, regardless of the level of injury. However, 30% may reach a small clinical functional improvement in the subacute to chronic phase following TSCI, particularly individuals sustaining severe deficits and older age, which may highlight the importance of functional compensation during this period for these patients.


Assuntos
Avaliação de Resultados em Cuidados de Saúde , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Doença Aguda , Adulto , Idoso , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Traumatismos da Medula Espinal/cirurgia , Índices de Gravidade do Trauma
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