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1.
Pediatr Emerg Care ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38776448

RESUMO

BACKGROUND: Due to the varied symptomatology and inconsistent features on neurologic exam, central nervous system (CNS) tumors are difficult to diagnosis in a timely manner. OBJECTIVE: To determine the clinical, neurological, and neuroimaging features of newly diagnosed CNS tumors presenting to the emergency department (ED). METHODS: We evaluated a retrospective cohort of 121 consecutive patients presenting to a tertiary care pediatric ED over 7 consecutive years with newly diagnosed CNS tumors. Clinical symptomatology, neurologic findings reported by emergency room and neurology physicians, neuroimaging features, and time to diagnosis were analyzed. RESULTS: A total of 116 (48 female, median age 8.0 years (interquartile range, 4.4-12.6), 52% Hispanic) presented to the ED (64% self-referred) diagnosed with a brain tumor (54% posterior fossa, 24% embryonal, 24% low-grade glioma, 16% high-grade glioma) resulting in hospital admission in 92% of cases. Five were diagnosed with extradural spinal, clivus, or orbital apex tumors. Symptomatology or duration did not differ when stratified by demographics, location, or histologic subtype. Moderate degree of concordance was observed among neurologic examinations performed by ED physicians and neurologists. Delayed diagnosis (median delay = 3.5 [1-7] months) was seen in 14% of patients, 13 with primary brain tumors (11 hemispheric, 2 brain stem). Six children with delayed diagnosis of low-grade glial tumors had a nonfocal neurologic examination in comparison to 5 patients with abnormal examinations observed with primary spinal or extradural CNS tumors. Four patients with posterior fossa tumors (3 medulloblastoma, 1 ependymoma) had normal/near normal neurologic examination at presentation despite posterior fossa symptomatology related to increased intracranial pressure. CONCLUSIONS: Our series highlights the complexity of symptomology and neurologic findings in children presenting to the ED with newly diagnosed CNS tumors who may have a normal neurologic examination. Standardization of symptom assessment and focused neurologic examinations may lead to earlier neuroimaging and prevent delayed diagnosis.

2.
Addict Biol ; 29(5): e13402, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38797559

RESUMO

Increases in harmful drinking among older adults indicate the need for a more thorough understanding of the relationship between later-life alcohol use and brain health. The current study investigated the relationships between alcohol use and progressive grey and white matter changes in older adults using longitudinal data. A total of 530 participants (aged 70 to 90 years; 46.0% male) were included. Brain outcomes assessed over 6 years included total grey and white matter volume, as well as volume of the hippocampus, thalamus, amygdala, corpus callosum, orbitofrontal cortex and insula. White matter integrity was also investigated. Average alcohol use across the study period was the main exposure of interest. Past-year binge drinking and reduction in drinking from pre-baseline were additional exposures of interest. Within the context of low-level average drinking (averaging 11.7 g per day), higher average amount of alcohol consumed was associated with less atrophy in the left (B = 7.50, pFDR = 0.010) and right (B = 5.98, pFDR = 0.004) thalamus. Past-year binge-drinking was associated with poorer white matter integrity (B = -0.013, pFDR = 0.024). Consuming alcohol more heavily in the past was associated with greater atrophy in anterior (B = -12.73, pFDR = 0.048) and posterior (B = -17.88, pFDR = 0.004) callosal volumes over time. Across alcohol exposures and neuroimaging markers, no other relationships were statistically significant. Within the context of low-level drinking, very few relationships between alcohol use and brain macrostructure were identified. Meanwhile, heavier drinking was negatively associated with white matter integrity.


Assuntos
Consumo de Bebidas Alcoólicas , Atrofia , Encéfalo , Substância Cinzenta , Imageamento por Ressonância Magnética , Substância Branca , Humanos , Masculino , Idoso , Feminino , Estudos Longitudinais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/efeitos dos fármacos , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Substância Branca/efeitos dos fármacos , Idoso de 80 Anos ou mais , Substância Cinzenta/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/efeitos dos fármacos , Atrofia/patologia , Envelhecimento/patologia , Envelhecimento/fisiologia , Consumo Excessivo de Bebidas Alcoólicas/patologia , Consumo Excessivo de Bebidas Alcoólicas/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tálamo/efeitos dos fármacos , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/efeitos dos fármacos , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/patologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Corpo Caloso/efeitos dos fármacos
4.
bioRxiv ; 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38559080

RESUMO

Diffuse Midline Gliomas (DMGs) are universally fatal, primarily pediatric malignancies affecting the midline structures of the central nervous system. Despite decades of clinical trials, treatment remains limited to palliative radiation therapy. A major challenge is the coexistence of molecularly distinct malignant cell states with potentially orthogonal drug sensitivities. To address this challenge, we leveraged established network-based methodologies to elucidate Master Regulator (MR) proteins representing mechanistic, non-oncogene dependencies of seven coexisting subpopulations identified by single-cell analysis-whose enrichment in essential genes was validated by pooled CRISPR/Cas9 screens. Perturbational profiles of 372 clinically relevant drugs helped identify those able to invert the activity of subpopulation-specific MRs for follow-up in vivo validation. While individual drugs predicted to target individual subpopulations-including avapritinib, larotrectinib, and ruxolitinib-produced only modest tumor growth reduction in orthotopic models, systemic co-administration induced significant survival extension, making this approach a valuable contribution to the rational design of combination therapy.

5.
Cell Rep ; 43(4): 114022, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38568806

RESUMO

Staphylococcus aureus causes the majority of skin and soft tissue infections, but this pathogen only transiently colonizes healthy skin. However, this transient skin exposure enables S. aureus to transition to infection. The initial adhesion of S. aureus to skin corneocytes is mediated by surface protein G (SasG). Here, phylogenetic analyses reveal the presence of two major divergent SasG alleles in S. aureus: SasG-I and SasG-II. Structural analyses of SasG-II identify a nonaromatic arginine in the binding pocket of the lectin subdomain that mediates adhesion to corneocytes. Atomic force microscopy and corneocyte adhesion assays indicate that SasG-II can bind to a broader variety of ligands than SasG-I. Glycosidase treatment results in different binding profiles between SasG-I and SasG-II on skin cells. In addition, SasG-mediated adhesion is recapitulated using differentiated N/TERT keratinocytes. Our findings indicate that SasG-II has evolved to adhere to multiple ligands, conferring a distinct advantage to S. aureus during skin colonization.


Assuntos
Aderência Bacteriana , Queratinócitos , Pele , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Humanos , Pele/microbiologia , Pele/metabolismo , Queratinócitos/microbiologia , Queratinócitos/metabolismo , Lectinas/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Filogenia , Ligação Proteica
7.
PLoS One ; 19(4): e0299101, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573913

RESUMO

The influence of intraspecific trait variation on species interactions makes trait-based approaches critical to understanding eco-evolutionary processes. Because species occupy habitats that are patchily distributed in space, species interactions are influenced not just by the degree of intraspecific trait variation but also the relative proportion of trait variation that occurs within- versus between-patches. Advancement in trait-based ecology hinges on understanding how trait variation is distributed within and between habitat patches across the landscape. We sampled larval spotted salamanders (Ambystoma maculatum) across six spatially discrete ponds to quantify within- and between-pond variation in mass, length, and various metrics associated with their relationship (scaling, body condition, shape). Across all traits, within-pond variation contributed more to total observed morphological variation than between-pond variation. Between-pond variation was not negligible, however, and explained 20-41% of total observed variation in measured traits. Between-pond variation was more pronounced in salamander tail morphology compared to head or body morphology, suggesting that pond-level factors more strongly influence tails than other body parts. We also observed differences in mass-length relationships across ponds, both in terms of scaling slopes and intercepts, though differences in the intercepts were much stronger. Preliminary evidence hinted that newly constructed ponds were a driver of the observed differences in mass-length relationships and morphometrics. General pond-level difference in salamander trait covariation suggest that allometric scaling of morphological traits is context dependent in patchy landscapes. Effects of pond age offer the hypothesis that habitat restoration through pond construction is a driver of variation in trait scaling, which managers may leverage to bolster trait diversity.


Assuntos
Ambystoma , Lagoas , Animais , Urodelos , Ecossistema , Ecologia
8.
Alzheimers Dement ; 20(6): 3972-3986, 2024 06.
Artigo em Italiano | MEDLINE | ID: mdl-38676366

RESUMO

INTRODUCTION: The LIfestyle for BRAin Health (LIBRA) index yields a dementia risk score based on modifiable lifestyle factors and is validated in Western samples. We investigated whether the association between LIBRA scores and incident dementia is moderated by geographical location or sociodemographic characteristics. METHODS: We combined data from 21 prospective cohorts across six continents (N = 31,680) and conducted cohort-specific Cox proportional hazard regression analyses in a two-step individual participant data meta-analysis. RESULTS: A one-standard-deviation increase in LIBRA score was associated with a 21% higher risk for dementia. The association was stronger for Asian cohorts compared to European cohorts, and for individuals aged ≤75 years (vs older), though only within the first 5 years of follow-up. No interactions with sex, education, or socioeconomic position were observed. DISCUSSION: Modifiable risk and protective factors appear relevant for dementia risk reduction across diverse geographical and sociodemographic groups. HIGHLIGHTS: A two-step individual participant data meta-analysis was conducted. This was done at a global scale using data from 21 ethno-regionally diverse cohorts. The association between a modifiable dementia risk score and dementia was examined. The association was modified by geographical region and age at baseline. Yet, modifiable dementia risk and protective factors appear relevant in all investigated groups and regions.


Assuntos
Demência , Estilo de Vida , Humanos , Demência/epidemiologia , Masculino , Feminino , Fatores de Risco , Idoso , Estudos Prospectivos , Incidência
12.
Gerontology ; 70(4): 351-360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38330922

RESUMO

INTRODUCTION: The data are limited for the association between osteoarthritis (OA) and cardiovascular disease (CVD) in community-based older populations and whether there is sex difference. This study aimed to examine the relationship between OA and prevalence and incidence of CVD over 10 years in community-dwelling older adults. METHODS: Data on self-reported OA, high cholesterol, hypertension, and type 2 diabetes were collected from 1,025 community-dwelling participants aged 70-90 years in the Sydney Memory and Ageing Study. The presence of CVD at baseline was defined as self-reported presence of stroke, heart attack, transient ischaemic attack, angina, aortic aneurysm, or claudication. The incidence of CVD was defined by a combination of incident self-reported CVD or CVD mortality at different follow-up timepoints over 10 years. RESULTS: At baseline, 395 (38.5%) participants self-reported OA (252 [44.6%] women, 143 [31.1%] men). Self-reported OA was associated with increased prevalence of CVD in women (OR 1.67, 95% CI 1.12-2.47) but not men (1.26, 0.80-1.98). In the total population, self-reported OA at baseline was associated with increased incidence of CVD at 4 years (OR 1.77, 95% CI 1.10-2.83), 6 years (1.59, 1.03-2.46), 8 years (1.56, 1.02-2.38), and 10 years (1.66, 1.10-2.50), but not at 2 years (1.43, 0.79-2.57). Significant associations were observed in female participants at 4, 8, and 10 years, with no significant associations seen in male participants. CONCLUSION: OA was associated with increased prevalence at baseline and incidence of CVD over 10 years in community-based older adults, especially women. Identifying those with OA to target their cardiovascular risk factors while managing their OA has the potential to reduce the burden of CVD in older people, particularly women.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Osteoartrite , Feminino , Humanos , Masculino , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/complicações , Vida Independente , Estudos de Coortes , Incidência , Prevalência , Fatores de Risco , Osteoartrite/epidemiologia , Envelhecimento
13.
Childs Nerv Syst ; 40(5): 1367-1375, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38240786

RESUMO

OBJECTIVE: Rathke cleft cysts (RCCs) are benign, epithelial-lined sellar lesions that arise from remnants of the craniopharyngeal duct. Due to their rarity in the pediatric population, data are limited regarding the natural history and optimal management of growing or symptomatic RCCs. We present our institutional experience with the surgical management of RCCs. METHODS: We performed a retrospective study of consecutive RCC patients ≤ 18 years old treated surgically at our institution between 2006 and 2022. RESULTS: Overall, 567 patients with a diagnosis of pituitary mass or cyst were identified. Of these, 31 had a histopathological diagnosis of RCC, 58% female and 42% male. The mean age was 13.2 ± 4.2 years. Presenting symptoms included headache (58%), visual changes (32%), and endocrinopathies or growth delay (26%); 13% were identified incidentally and subsequently demonstrated growth on serial imaging. Six percent presented with symptomatic intralesional hemorrhage. Surgical approach was transsphenoidal for 90% of patients and orbitozygomatic for 10%. Preoperative headaches resolved in 61% of patients and preoperative visual deficits improvement in 55% after surgery. New pituitary axis deficits were seen in 9.7% of patients. Only two complications occurred from a first-time surgery: one cerebrospinal fluid leak requiring lumbar drain placement, and one case of epistaxis requiring cauterization. No patients experienced new visual or neurological deficits. Patients were followed postoperatively with serial imaging at a mean follow-up was 62.9 ± 58.4 months. Recurrence requiring reoperation occurred in 32% of patients. Five-year progression-free survival was 47.9%. Except for one patient with multiple neurological deficits from a concurrent tectal glioma, all patients had a modified Rankin Scale score of 0 or 1 (good outcome) at last follow-up. CONCLUSION: Due to their secretory epithelium, pediatric RCCs may demonstrate rapid growth and can cause symptoms due to local mass effect. Surgical management of symptomatic or growing pediatric RCCs via cyst fenestration or partial resection of the cyst wall can be performed safely, with good neurologic outcomes. There is a nontrivial risk of endocrinologic injury, and long-term follow up is needed due to high recurrence rates.


Assuntos
Carcinoma de Células Renais , Cistos do Sistema Nervoso Central , Cistos , Neoplasias Renais , Humanos , Criança , Masculino , Feminino , Adolescente , Estudos Retrospectivos , Cistos do Sistema Nervoso Central/cirurgia
14.
Nat Cancer ; 5(5): 791-807, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38228835

RESUMO

Brain tumors in children are a devastating disease in a high proportion of patients. Owing to inconsistent results in clinical trials in unstratified patients, the role of immunotherapy remains unclear. We performed an in-depth survey of the single-cell transcriptomes and clonal relationship of intra-tumoral T cells from children with brain tumors. Our results demonstrate that a large fraction of T cells in the tumor tissue are clonally expanded with the potential to recognize tumor antigens. Such clonally expanded T cells display enrichment of transcripts linked to effector function, tissue residency, immune checkpoints and signatures of neoantigen-specific T cells and immunotherapy response. We identify neoantigens in pediatric brain tumors and show that neoantigen-specific T cell gene signatures are linked to better survival outcomes. Notably, among the patients in our cohort, we observe substantial heterogeneity in the degree of clonal expansion and magnitude of T cell response. Our findings suggest that characterization of intra-tumoral T cell responses may enable selection of patients for immunotherapy, an approach that requires prospective validation in clinical trials.


Assuntos
Neoplasias Encefálicas , Linfócitos T , Humanos , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Criança , Linfócitos T/imunologia , Antígenos de Neoplasias/imunologia , Imunoterapia/métodos , Pré-Escolar , Masculino , Feminino , Adolescente , Linfócitos do Interstício Tumoral/imunologia , Análise de Célula Única/métodos , Transcriptoma , Células Clonais
15.
BMJ Case Rep ; 17(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191218

RESUMO

The opioid epidemic has become a significant public health crisis worldwide. With the rise in popularity of fentanyl, opioid overdoses continue to rise at unprecedented rates. Unfortunately, young children have become collateral damage in the face of the opioid epidemic. Accidental exposures and ingestions are the leading cause of opioid overdose in this age group and can result in significant acute complications, long-term sequelae and even death. We present the case of a toddler with accidental fentanyl ingestion who experienced seizures and required intubation for respiratory distress. He was found to have notable diffusion restriction cerebellar changes on MRI and ultimately discharged with normal neurological function. Our case adds to the growing literature of the clinical presentation and neuroimaging features associated with opioid toxicity in young children.


Assuntos
Overdose de Opiáceos , Masculino , Humanos , Pré-Escolar , Neuroimagem , Progressão da Doença , Analgésicos Opioides , Fentanila
17.
J Vasc Surg Cases Innov Tech ; 10(1): 101380, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38226318

RESUMO

Chronic radiation-induced arterial injury is generally predictable by known tumor types and anatomic location. We present the first case of radiation-induced chronic aortic occlusion associated with a small pelvis secondary to the treatment of childhood Ewing sarcoma. The patient presented with profound claudication and accelerated atherosclerosis obliterans of the aortoiliac system and failed endovascular treatment. Successful aortic reconstruction was performed. This case highlights the long-term effects of chemoradiation to the aortoiliac segment and pelvic bones in a child, and the technical challenges of vascular reconstruction in an underdeveloped irradiated pelvis.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36852741

RESUMO

Cognitive, social, and physical activities, collectively linked to cognitive reserve, are associated with better late-life cognitive outcomes. To better understand the building of cognitive reserve, we investigated which of these activities, during which stages of life, had the strongest associations with late-life cognitive performance. From the Sydney Memory and Aging Study, 546 older Australians, who were community-dwelling and without a dementia diagnosis at recruitment (Mage 80.13 years, 52.2% female), were asked about their engagement in social, physical, and cognitive activities throughout young adulthood (YA), midlife (ML), and late-life (LL). Comprehensive neuropsychological testing administered biennially over 6 years measured baseline global cognition and cognitive decline. In our study, YA, but not ML nor LL, cognitive activity was significantly associated with late-life global cognition (ß = 0.315, p < .001). A follow-up analysis pointed to the formal education component of the YA cognitive activity measure, rather than YA cognitive leisure activities, as a significant predictor of better late-life global cognition (ß = 0.146, p = .003). YA social activity and LL cognitive activity were significantly associated with less cognitive decline (ß = 0.023, p < .001, and ß = 0.016, p = .022, respectively). Physical activity was not found to be associated with global cognition or cognitive decline. Overall, YA cognitive activity was associated with better late-life cognition, and YA social and LL cognitive activities were associated with less cognitive decline. Formal education emerges as the key contributor in the association between YA cognitive activity and late-life global cognition.


Assuntos
Envelhecimento , Disfunção Cognitiva , Reserva Cognitiva , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Envelhecimento/psicologia , População Australasiana , Austrália , Cognição , Estudos de Coortes
19.
Psychiatry Clin Neurosci ; 78(4): 229-236, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113307

RESUMO

AIM: Recovery from stroke is adversely affected by neuropsychiatric complications, cognitive impairment, and functional disability. Better knowledge of their mutual relationships is required to inform effective interventions. Network theory enables the conceptualization of symptoms and impairments as dynamic and mutually interacting systems. We aimed to identify interactions of poststroke complications using network analysis in diverse stroke samples. METHODS: Data from 2185 patients were sourced from member studies of STROKOG (Stroke and Cognition Consortium), an international collaboration of stroke studies. Networks were generated for each cohort, whereby nodes represented neuropsychiatric symptoms, cognitive deficits, and disabilities on activities of daily living. Edges characterized associations between them. Centrality measures were used to identify hub items. RESULTS: Across cohorts, a single network of interrelated poststroke complications emerged. Networks exhibited dissociable depression, apathy, fatigue, cognitive impairment, and functional disability modules. Worry was the most central symptom across cohorts, irrespective of the depression scale used. Items relating to activities of daily living were also highly central nodes. Follow-up analysis in two studies revealed that individuals who worried had more densely connected networks than those free of worry (CASPER [Cognition and Affect after Stroke: Prospective Evaluation of Risks] study: S = 9.72, P = 0.038; SSS [Sydney Stroke Study]: S = 13.56, P = 0.069). CONCLUSION: Neuropsychiatric symptoms are highly interconnected with cognitive deficits and functional disabilities resulting from stroke. Given their central position and high level of connectedness, worry and activities of daily living have the potential to drive multimorbidity and mutual reinforcement between domains of poststroke complications. Targeting these factors early after stroke may have benefits that extend to other complications, leading to better stroke outcomes.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Acidente Vascular Cerebral , Humanos , Depressão/psicologia , Atividades Cotidianas/psicologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Transtornos Cognitivos/complicações , Disfunção Cognitiva/complicações , Cognição
20.
bioRxiv ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-38045275

RESUMO

Staphylococcus aureus causes the majority of skin and soft tissue infections, but this pathogen only transiently colonizes healthy skin. However, this transient skin exposure enables S. aureus to transition to infection. Initial adhesion of S. aureus to skin corneocytes is mediated by surface protein G (SasG). Here, phylogenetic analyses reveal the presence of two major divergent SasG alleles in S. aureus, SasG-I and SasG-II. Structural analyses of SasG-II identified a unique non-aromatic arginine in the binding pocket of the lectin subdomain that mediates adhesion to corneocytes. Atomic force microscopy and corneocyte adhesion assays indicated SasG-II can bind to a broader variety of ligands than SasG-I. Glycosidase treatment resulted in different binding profiles between SasG-I and SasG-II on skin cells. Additionally, SasG-mediated adhesion was recapitulated using differentiated N/TERT keratinocytes. Our findings indicate that SasG-II has evolved to adhere to multiple ligands, conferring a distinct advantage to S. aureus during skin colonization.

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