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1.
Proc Natl Acad Sci U S A ; 121(22): e2316149121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768342

RESUMO

Speech impediments are a prominent yet understudied symptom of Parkinson's disease (PD). While the subthalamic nucleus (STN) is an established clinical target for treating motor symptoms, these interventions can lead to further worsening of speech. The interplay between dopaminergic medication, STN circuitry, and their downstream effects on speech in PD is not yet fully understood. Here, we investigate the effect of dopaminergic medication on STN circuitry and probe its association with speech and cognitive functions in PD patients. We found that changes in intrinsic functional connectivity of the STN were associated with alterations in speech functions in PD. Interestingly, this relationship was characterized by altered functional connectivity of the dorsolateral and ventromedial subdivisions of the STN with the language network. Crucially, medication-induced changes in functional connectivity between the STN's dorsolateral subdivision and key regions in the language network, including the left inferior frontal cortex and the left superior temporal gyrus, correlated with alterations on a standardized neuropsychological test requiring oral responses. This relation was not observed in the written version of the same test. Furthermore, changes in functional connectivity between STN and language regions predicted the medication's downstream effects on speech-related cognitive performance. These findings reveal a previously unidentified brain mechanism through which dopaminergic medication influences speech function in PD. Our study sheds light into the subcortical-cortical circuit mechanisms underlying impaired speech control in PD. The insights gained here could inform treatment strategies aimed at mitigating speech deficits in PD and enhancing the quality of life for affected individuals.


Assuntos
Idioma , Doença de Parkinson , Fala , Núcleo Subtalâmico , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Núcleo Subtalâmico/fisiopatologia , Núcleo Subtalâmico/efeitos dos fármacos , Masculino , Fala/fisiologia , Fala/efeitos dos fármacos , Feminino , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética , Dopamina/metabolismo , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiopatologia , Cognição/efeitos dos fármacos , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico
2.
Chem Rev ; 124(5): 2327-2351, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38408312

RESUMO

Polyethylene deconstruction to reusable smaller molecules is hindered by the chemical inertness of its hydrocarbon chains. Pyrolysis and related approaches commonly require high temperatures, are energy-intensive, and yield mixtures of multiple classes of compounds. Selective cleavage reactions under mild conditions (

3.
J Am Chem Soc ; 146(18): 12645-12655, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38651821

RESUMO

The increased production of plastics is leading to the accumulation of plastic waste and depletion of limited fossil fuel resources. In this context, we report a strategy to create polymers that can undergo controlled depolymerization by linking renewable feedstocks with siloxane bonds. α,ω-Diesters and α,ω-diols containing siloxane bonds were synthesized from an alkenoic ester derived from castor oil and then polymerized with varied monomers, including related biobased monomers. In addition, cyclic monomers derived from this alkenoic ester and hydrosiloxanes were prepared and cyclized to form a 26-membered macrolactone containing a siloxane unit. Sequential ring-opening polymerization of this macrolactone and lactide afforded an ABA triblock copolymer. This set of polymers containing siloxanes underwent programmed depolymerization into monomers in protic solvents or with hexamethyldisiloxane and an acid catalyst. Monomers afforded by the depolymerization of polyesters containing siloxane linkages were repolymerized to demonstrate circularity in select polymers. Evaluation of the environmental stability of these polymers toward enzymatic degradation showed that they undergo enzymatic hydrolysis by a fungal cutinase from Fusarium solani. Evaluation of soil microbial metabolism of monomers selectively labeled with 13C revealed differential metabolism of the main chain and side chain organic groups by soil microbes.


Assuntos
Fusarium , Polimerização , Siloxanas , Siloxanas/química , Óleos de Plantas/química , Polímeros/química , Estrutura Molecular , Hidrolases de Éster Carboxílico
4.
J Int Neuropsychol Soc ; 30(4): 313-327, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38014546

RESUMO

OBJECTIVE: Subtle changes in memory, attention, and spatial navigation abilities have been associated with preclinical Alzheimer disease (AD). The current study examined whether baseline AD biomarkers are associated with self- and informant-reported decline in memory, attention, and spatial navigation. METHOD: Clinically normal (Clinical Dementia Rating Scale (CDR®) = 0) adults aged 56-93 (N = 320) and their informants completed the memory, divided attention, and visuospatial abilities (which assesses spatial navigation) subsections of the Everyday Cognition Scale (ECog) annually for an average of 4 years. Biomarker data was collected within (±) 2 years of baseline (i.e., cerebrospinal fluid (CSF) p-tau181/Aß42 ratio and hippocampal volume). Clinical progression was defined as CDR > 0 at time of final available ECog. RESULTS: Self- and informant-reported memory, attention, and spatial navigation significantly declined over time (ps < .001). Baseline AD biomarkers were significantly associated with self- and informant-reported decline in cognitive ability (ps < .030), with the exception of p-tau181/Aß42 ratio and self-reported attention (p = .364). Clinical progression did not significantly moderate the relationship between AD biomarkers and decline in self- or informant-reported cognitive ability (ps > .062). Post-hoc analyses indicated that biomarker burden was also associated with self- and informant-reported decline in total ECog (ps < .002), and again clinical progression did not significantly moderate these relationships (ps > .299). CONCLUSIONS: AD biomarkers at baseline may indicate risk of decline in self- and informant-reported change in memory, attention, and spatial navigation ability. As such, subjectively reported decline in these domains may have clinical utility in tracking the subtle cognitive changes associated with the earliest stages of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Navegação Espacial , Humanos , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Progressão da Doença , Atenção , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/líquido cefalorraquidiano
5.
J Int Neuropsychol Soc ; 30(3): 232-243, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37642015

RESUMO

OBJECTIVE: Preclinical Alzheimer disease (AD) has been associated with subtle changes in memory, attention, and spatial navigation abilities. The current study examined whether self- and informant-reported domain-specific cognitive changes are sensitive to AD-associated biomarkers. METHOD: Clinically normal adults aged 56-93 and their informants completed the memory, divided attention, and visuospatial abilities (which assesses spatial navigation) subsections of the Everyday Cognition Scale (ECog). Reliability and validity of these subsections were examined using Cronbach's alpha and confirmatory factor analysis. Logistic regression was used to examine the ability of ECog subsections to predict AD-related biomarkers (cerebrospinal fluid (CSF) ptau181/Aß42 ratio (N = 371) or hippocampal volume (N = 313)). Hierarchical logistic regression was used to examine whether the self-reported subsections continued to predict biomarkers when controlling for depressive symptomatology if available (N = 197). Additionally, logistic regression was used to examine the ability of neuropsychological composites assessing the same or similar cognitive domains as the subsections (memory, executive function, and visuospatial abilities) to predict biomarkers to allow for comparison of the predictive ability of subjective and objective measures. RESULTS: All subsections demonstrated appropriate reliability and validity. Self-reported memory (with outliers removed) was the only significant predictor of AD biomarker positivity (i.e., CSF ptau181/Aß42 ratio; p = .018) but was not significant when examined in the subsample with depressive symptomatology available (p = .517). Self-reported memory (with outliers removed) was a significant predictor of CSF ptau181/Aß42 ratio biomarker positivity when the objective memory composite was included in the model. CONCLUSIONS: ECog subsections were not robust predictors of AD biomarker positivity.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Navegação Espacial , Humanos , Doença de Alzheimer/psicologia , Reprodutibilidade dos Testes , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Testes Neuropsicológicos , Biomarcadores/líquido cefalorraquidiano , Atenção , Fragmentos de Peptídeos/líquido cefalorraquidiano , Disfunção Cognitiva/psicologia
6.
Nature ; 559(7712): 89-93, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29973732

RESUMO

The potential link between erosion rates at the Earth's surface and changes in global climate has intrigued geoscientists for decades1,2 because such a coupling has implications for the influence of silicate weathering3,4 and organic-carbon burial5 on climate and for the role of Quaternary glaciations in landscape evolution1,6. A global increase in late-Cenozoic erosion rates in response to a cooling, more variable climate has been proposed on the basis of worldwide sedimentation rates7. Other studies have indicated, however, that global erosion rates may have remained steady, suggesting that the reported increases in sediment-accumulation rates are due to preservation biases, depositional hiatuses and varying measurement intervals8-10. More recently, a global compilation of thermochronology data has been used to infer a nearly twofold increase in the erosion rate in mountainous landscapes over late-Cenozoic times6. It has been contended that this result is free of the biases that affect sedimentary records11, although others have argued that it contains biases related to how thermochronological data are averaged12 and to erosion hiatuses in glaciated landscapes13. Here we investigate the 30 locations with reported accelerated erosion during the late Cenozoic6. Our analysis shows that in 23 of these locations, the reported increases are a result of a spatial correlation bias-that is, combining data with disparate exhumation histories, thereby converting spatial erosion-rate variations into temporal increases. In four locations, the increases can be explained by changes in tectonic boundary conditions. In three cases, climatically induced accelerations are recorded, driven by localized glacial valley incision. Our findings suggest that thermochronology data currently have insufficient resolution to assess whether late-Cenozoic climate change affected erosion rates on a global scale. We suggest that a synthesis of local findings that include location-specific information may help to further investigate drivers of global erosion rates.

7.
Neonatal Netw ; 43(2): 92-104, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38599771

RESUMO

Cytomegalovirus (CMV), a beta-herpes virus, is the most common viral infection in infants. Transmission may occur congenitally (cCMV) or postnatally (pCMV). Early detection and intervention are crucial in reducing morbidities, notable developmental delays, and sensorineural hearing loss. However, more than 90% of infants are asymptomatic at birth. Treatment involves intravenous ganciclovir or the oral prodrug, valganciclovir, drugs usually reserved for use with symptomatic infants because of the toxicity profile. Research currently supports standardized antenatal CMV screening and treatment of affected pregnant patients with hyperimmune globulin as well as vaccination against CMV in unaffected pregnant patients, although widespread adoption is lacking. Standardized postnatal CMV screening is a proven, cost-effective way to detect and diagnose CMV and optimize outcomes across the lifespan. This article presents a case series of cCMV and pCMV and a review of the state of science of CMV as well as promising scientific advances that are on the horizon.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Feminino , Humanos , Recém-Nascido , Gravidez , Antivirais/uso terapêutico , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/tratamento farmacológico , Ganciclovir/farmacologia , Ganciclovir/uso terapêutico , Triagem Neonatal , Valganciclovir/farmacologia , Valganciclovir/uso terapêutico
8.
Cancer ; 129(19): 2946-2965, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37489837

RESUMO

BACKGROUND: Social isolation and connectedness are social determinants of health that have demonstrated effects on cancer-related outcomes. These constructs have been systematically evaluated among pediatric and older adult cancer populations. In this review, the authors evaluated the prevalence, correlates, and psychosocial implications of social isolation and connectedness among young adult (YA) cancer survivors aged 18-39 years. METHODS: Peer-reviewed articles published in English before June 2021 were identified from database searches and included articles' reference lists according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included articles described studies that assessed social isolation and/or connectedness among YA cancer survivors. RESULTS: In total, 5094 unique records were identified; 4143 were excluded after title/abstract screening, and 907 were excluded after full-text review. Forty-four articles were included. Few studies used validated measures or directly assessed social isolation or connectedness. Social isolation was similarly prevalent among YAs and older cancer survivors and noncancer populations. Demographic, clinical, and behavioral risk and protective factors for social isolation were identified. Social isolation was related to worse psychological well-being, whereas social connectedness was often, but not always, related to better psychological well-being. CONCLUSIONS: This growing literature underscores the relevance of social isolation and connectedness as important health determinants among YA cancer survivors. The identified risk and protective factors can identify YAs who especially may benefit from screening for social isolation. Future studies are needed that directly, reliably, and validly evaluate social isolation and connectedness to inform the development of interventions to decrease isolation and increase connectedness.


Assuntos
Sobreviventes de Câncer , Neoplasias , Humanos , Adulto Jovem , Criança , Idoso , Isolamento Social/psicologia , Neoplasias/psicologia
9.
Anal Chem ; 95(22): 8560-8568, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37226811

RESUMO

Molecular weight (MW) is a key control of plastic polymer properties and their fate in the environment. However, the primary tool used to determine plastic MW, gel permeation chromatography (GPC), has major limitations, such as low precision and accuracy, requirements for dedicated instrumentation, production of high volumes of hazardous waste, and large sample sizes. In this study, we describe, validate, and apply a diffusion-ordered spectroscopy (DOSY) method for polymer MW determinations, with a focus on applications for consumer plastics. Several experimental conditions were systematically optimized and tested to validate the DOSY method, including the selection of pulse sequences, the effect of sample concentration, cross-validation with multiple sets of external standards, and long-term instrumental stability. Validation was performed for a wide range of polymers, solvents, and temperatures, highlighting its potential for broad applicability. A preliminary screening of polystyrene and polyethylene terephthalate consumer products revealed widely varying MWs (up to two-fold) for products made of the same polymer type. A preliminary experiment was also conducted to track the decrease in polystyrene MW via photochemical chain scission reactions, finding a 20% reduction in MW after less than 1 week of irradiation. Collectively, our results demonstrate the potential for DOSY to provide high-throughput, accurate, and precise measures of polymer MW, as well as the evolution of polymer MW during environmental weathering processes, such as photochemical degradation. We conclude with a discussion of (i) the many advantages of DOSY compared to GPC, (ii) future developments to enhance the depth of information obtained from DOSY, and (iii) approaches to broaden the accessibility of this promising analytical method to the research community.

10.
Am J Otolaryngol ; 44(1): 103684, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36343506

RESUMO

OBJECTIVE: There is hesitation to offer pediatric patients rhinoplasty due to concerns about postoperative effect on midface growth. A cross-sectional survey of members of the American Academy of Facial Plastic and Reconstructive Surgery was conducted regarding practice information and attitudes towards pediatric septorhinoplasty. The goal of the study is to describe the current attitudes on pediatric septorhinoplasty. STUDY DESIGN: Cross-sectional survey. SETTING: Community members of the American Academy of Facial Plastic and Reconstructive Surgery society. METHODS: A 19-question survey was distributed to surgeons surveying background information and current attitudes towards pediatric septorhinoplasty practices. Fisher's exact tests were implemented using Monte Carlo methods. RESULTS: There were 94 total respondents. A majority believed septorhinoplasty is safe in patients <16 years of age (n = 68, 72.34 %) with most choosing either 16 years (n = 30, 31.91 %) or 14 years (n = 29, 30.85 %) as the minimum age to consider the procedure. A majority of respondents would not perform any nasal procedures in patients ≤12 years (n = 40, 43.48 %). CONCLUSION: Trends in pediatric rhinoplasty practices have evolved overtime. Despite prior beliefs and studies cautioning against performing septorhinoplasty in pediatric patients (<16 years of age), a majority of practicing facial plastic surgeons believe that pediatric septorhinoplasty can be performed in patients >14 years old. LEVEL OF EVIDENCE: IV.


Assuntos
Procedimentos de Cirurgia Plástica , Rinoplastia , Cirurgiões , Cirurgia Plástica , Humanos , Estados Unidos , Criança , Adolescente , Rinoplastia/métodos , Estudos Transversais , Inquéritos e Questionários , Face/cirurgia , Cirurgia Plástica/métodos
11.
Angew Chem Int Ed Engl ; 62(43): e202310729, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37675615

RESUMO

Monomers sourced from waste or biomass are often mixtures of different chain lengths; e.g. catalytic oxidation of polyethylene waste yields mixtures of dicarboxylic acids (DCAs). Yet, polyesters synthesized from such monomer mixtures have rarely been studied. We report polyesters based on multiple linear aliphatic DCAs, present in chain length distributions that vary in their centers and ranges. We demonstrate that these materials can adopt high-density polyethylene-like solid state structures, and are ductile (e.g. Et 610 MPa), allowing for injection molding, or film and fiber extrusion. Melting and crystallization points of the polyesters show no odd-even effects as dipoles cannot favorably align in the crystal, similar to traditional odd carbon numbered, long-chain DCA polyesters. Biodegradation studies of 13 C-labelled polyesters in soil reveal rapid mineralization, and depolymerization by methanolysis indicates suitability for closed-loop recycling.

12.
Small ; 18(19): e2200125, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35388947

RESUMO

The ability of pathogens to develop drug resistance is a global health challenge. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents an urgent need wherein several variants of concern resist neutralization by monoclonal antibody (mAb) therapies and vaccine-induced sera. Decoy nanoparticles-cell-mimicking particles that bind and inhibit virions-are an emerging class of therapeutics that may overcome such drug resistance challenges. To date, quantitative understanding as to how design features impact performance of these therapeutics is lacking. To address this gap, this study presents a systematic, comparative evaluation of various biologically derived nanoscale vesicles, which may be particularly well suited to sustained or repeated administration in the clinic due to low toxicity, and investigates their potential to inhibit multiple classes of model SARS-CoV-2 virions. A key finding is that such particles exhibit potent antiviral efficacy across multiple manufacturing methods, vesicle subclasses, and virus-decoy binding affinities. In addition, these cell-mimicking vesicles effectively inhibit model SARS-CoV-2 variants that evade mAbs and recombinant protein-based decoy inhibitors. This study provides a foundation of knowledge that may guide the design of decoy nanoparticle inhibitors for SARS-CoV-2 and other viral infections.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais/uso terapêutico , Antivirais , Humanos , Glicoproteína da Espícula de Coronavírus/metabolismo
13.
J Sleep Res ; 31(3): e13505, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34651360

RESUMO

Previous research shows that adults with children have poorer sleep overall than adults without children. Poorer sleep is associated with experiencing more frequent and severe stressors. The daily link between sleep and stressors may differ by parenting status; yet this potential difference has not been addressed, especially in nurses who provide care both at work and home. This study examined whether the sleep-stress relationship is stronger for nurses with children than those without. During 14 days of ecological momentary assessment, 60 hospital nurses (24 parents) reported their previous night's sleep characteristics upon waking. Three times daily, they also reported whether they encountered any stressors and how severe those stressors were. Associations were assessed at the within- and between-person levels with parenting status as a between-person moderator. After controlling for covariates, previous night's poorer sleep quality, lower sleep sufficiency, and shorter time in bed were associated with perceiving more frequent or severe stressors the following day. Some of these daily associations were moderated by parenting status, such that the sleep-stressor link was only significant for parents, with the magnitude of association being stronger for those with 2+ children relative to 1 child. These findings suggest that nurses with children are at greater risk for a stronger linkage between poorer sleep and greater stressor frequency and severity. A stronger sleep-stressor relationship could have compounding effects on health. Improving sleep in this group may be critical to reduce their stress and improve the quality of care across work and home.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Sono , Adulto , Criança , Avaliação Momentânea Ecológica , Humanos , Pais
14.
Psychooncology ; 31(9): 1519-1526, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35726386

RESUMO

OBJECTIVE: This study aimed to describe considerations for developing supportive care interventions targeted to head and neck cancer (HNC) survivors. METHODS: One-time semi-structured interviews (N = 33) were conducted with HNC survivors who had recently finished treatment (n = 20) and HNC providers (e.g., physicians, nurses; n = 13). Interviews were transcribed verbatim and coded using inductive applied thematic analysis techniques to identify themes. RESULTS: HNC survivors (75% male; M = 61 years old) and providers (54% physicians; 62% female) were unanimously supportive of developing HNC-specific supportive care interventions. Participants described potential benefits of offering interventions at various points throughout the HNC treatment and survivorship trajectory rather than at a single critical time. Many participants preferred group-based interventions because of the high value of peer-support. Others described how group interventions may not be appropriate for all HNC survivors due to risks for negative social comparisons and exacerbated anxiety. Participants suggested topics that should be addressed in HNC-specific interventions including education about acute and long-term side effects, symptom management, nutritional support, relationship/social role changes, grief/loss, and fear of recurrence. CONCLUSIONS: HNC-specific supportive care interventions are critically needed, as survivors experience persistent symptoms and distinct psychosocial concerns that impact quality of life. Findings from this study can inform the development of supportive care interventions targeted to the unique psychosocial concerns of HNC survivors.


Assuntos
Sobreviventes de Câncer , Neoplasias de Cabeça e Pescoço , Sobreviventes de Câncer/psicologia , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Sobreviventes , Sobrevivência
15.
Eur Radiol ; 32(10): 7068-7078, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35779090

RESUMO

OBJECTIVES: To provide a standard for total abdominal muscle mass (TAM) quantification on computed tomography (CT) and investigate its association with cardiovascular risk in a primary prevention setting. METHODS: We included 3016 Framingham Heart Study participants free of cardiovascular disease (CVD) who underwent abdominal CT between 2002 and 2005. On a single CT slice at the level of L3/L4, we segmented (1) TAM-Area, (2) TAM-Index (= TAM-Area/height) and, (3) TAM-Fraction (= TAM-Area/total cross-sectional CT-area). We tested the association of these muscle mass measures with prevalent and incident cardiometabolic risk factors and incident CVD events during a follow-up of 11.0 ± 2.7 years. RESULTS: In this community-based sample (49% women, mean age: 50.0 ± 10.0 years), all muscle quantity measures were significantly associated with prevalent and incident cardiometabolic risk factors and CVD events. However, only TAM-Fraction remained significantly associated with key outcomes (e.g., adj. OR 0.68 [0.55, 0.84] and HR 0.73 [0.57, 0.92] for incident hypertension and CVD events, respectively) after adjustment for age, sex, body mass index, and waist circumference. Moreover, only higher TAM-Fraction was associated with a lower risk (e.g., adj. OR: 0.56 [0.36-0.89] for incident diabetes versus TAM-Area: adj. OR 1.26 [0.79-2.01] and TAM-Index: 1.09 [0.75-1.58]). CONCLUSION: TAM-Fraction on a single CT slice at L3/L4 is a novel body composition marker of cardiometabolic risk in a primary prevention setting that has the potential to improve risk stratification beyond traditional measures of obesity. KEY POINTS: • In this analysis of the Framingham Heart Study (n = 3016), TAM-F on a single slice CT was more closely associated with prevalent and incident cardiometabolic risk factors as compared to TAM alone or TAM indexed to body surface area. • TAM-F on a single abdominal CT slice at the level of L3/L4 could serve as a standard measure of muscle mass and improve risk prediction.


Assuntos
Doenças Cardiovasculares , Tomografia Computadorizada por Raios X , Músculos Abdominais , Adulto , Índice de Massa Corporal , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco
16.
Alzheimer Dis Assoc Disord ; 36(1): 15-21, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34966024

RESUMO

Subtle changes in objective spatial navigation ability have been observed in the preclinical stage of Alzheimer disease (AD) cross-sectionally and have been found to predict clinical progression. However, longitudinal change in self-reported spatial navigation ability in preclinical AD has yet to be examined. The current study examined whether AD biomarkers suggestive of preclinical AD at baseline spatial navigation assessment and APOE genotype predicted decline in self-reported spatial navigation ability and whether APOE genotype moderated the association of AD biomarkers with change in self-reported spatial navigation. Clinically normal (Clinical Dementia Rating Scale=0) adults aged 56 to 90 completed the Santa Barbara Sense of Direction Scale (SBSOD) annually for an average of 2.73 years. Biomarker data was collected within +/-2 years of baseline (ie, cerebrospinal fluid Aß42, p-tau181, p-tau181/Aß42 ratio, positron emission tomography imaging with Florbetapir or Pittsburgh Compound-B, and hippocampal volume). APOE genotyping was obtained for all participants. SBSOD demonstrated a nonsignificant trend toward a decline over time (P=0.082). AD biomarkers did not predict change in self-reported spatial navigation (all Ps>0.163). APOE genotype did not moderate the relationship between AD biomarkers and self-reported spatial navigation in planned analyses (all Ps>0.222). Results suggest that self-reported spatial navigation ability, as estimated with the SBSOD, may be limited as a measure of subtle cognitive change in the preclinical stage of AD.


Assuntos
Doença de Alzheimer , Navegação Espacial , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Autorrelato , Proteínas tau/líquido cefalorraquidiano
17.
Environ Sci Technol ; 56(19): 13810-13819, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36103552

RESUMO

Sunlight chemically transforms marine plastics into a suite of products, with formulation─the specific mixture of polymers and additives─driving rates and products. However, the effect of light-driven transformations on subsequent microbial lability is poorly understood. Here, we examined the interplay between photochemical and biological degradation of fabrics made from cellulose diacetate (CDA), a biobased polymer used commonly in consumer products. We also examined the influence of ∼1% titanium dioxide (TiO2), a common pigment and photocatalyst. We sequentially exposed CDA to simulated sunlight and native marine microbes to understand how photodegradation influences metabolic rates and pathways. Nuclear magnetic resonance spectroscopy revealed that sunlight initiated chain scission reactions, reducing CDA's average molecular weight. Natural abundance carbon isotope measurements demonstrated that chain scission ultimately yields CO2, a newly identified abiotic loss term of CDA in the environment. Measurements of fabric mass loss and enzymatic activities in seawater implied that photodegradation enhanced biodegradation by performing steps typically facilitated by cellulase. TiO2 accelerated CDA photodegradation, expediting biodegradation. Collectively, these findings (i) underline the importance of formulation in plastic's environmental fate and (ii) suggest that overlooking synergy between photochemical and biological degradation may lead to overestimates of marine plastic persistence.


Assuntos
Celulases , Luz Solar , Dióxido de Carbono , Isótopos de Carbono , Celulose/análogos & derivados , Oceanos e Mares , Plásticos/química , Polímeros , Titânio/química
18.
Nurs Res ; 71(2): 119-127, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35212497

RESUMO

BACKGROUND: Mandated social distancing practices and quarantines in response to COVID-19 have resulted in challenges for research on healthcare workers, such as hospital nurses. It remains unknown whether nursing studies utilizing complex methodology like sleep actigraphy and ecological momentary assessment (EMA) can be conducted remotely without compromising data quality. OBJECTIVES: We aimed to (a) disseminate our remote study protocol for sleep actigraphy and EMA data from hospital nurses during COVID-19, (b) assess feasibility and acceptability of this approach for studies on hospital nurses, and (c) examine the reliability and ecological validity of sleep characteristics measured across 14 days. METHODS: Using an online platform, we provided 86 outpatient nurses from a cancer hospital with detailed video/text instructions regarding the study and facilitated virtual study onboarding meetings. Feasibility was assessed by comparing adherence rates to a similar in-person study of nurses from the same hospital; acceptability was evaluated through content analysis of qualitative study feedback. Multilevel modeling was conducted to assess changes in sleep characteristics as a function of study day and daily stressful experiences. RESULTS: Adherence to EMA (91.8%) and actigraphy (97.9%) was high. EMA adherence was higher than the in-person study of inpatient day-shift nurses from the same hospital. Content analyses revealed primarily positive feedback, with 51.2% reporting "easy, clear, simple onboarding" and 16.3% reporting the website was "helpful." Six participants provided only negative feedback. Sleep characteristics did not change as a function of study day except for self-reported quality, which increased slightly during Week 1 and regressed toward baseline after that. A higher incidence of stressor days or higher stressor severity followed nights with shorter-than-usual time in bed or poorer-than-usual sleep quality, supporting the ecological validity for these methods of assessing sleep in nurses. DISCUSSION: Findings suggest that a fully remote study protocol for EMA and actigraphy studies in nursing yields robust feasibility, acceptability, reliability, and validity. Given the busy schedules of nurses, the convenience of this approach may be preferable to traditional in-person data collection. Lessons learned from COVID-19 may apply to improving nursing research postpandemic.


Assuntos
Actigrafia , COVID-19 , COVID-19/epidemiologia , Avaliação Momentânea Ecológica , Humanos , Pandemias , Reprodutibilidade dos Testes , SARS-CoV-2
19.
J Neurochem ; 157(6): 1838-1849, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33638177

RESUMO

Zinc has been suggested to act as an intracellular signaling molecule due to its regulatory effects on numerous protein targets including enzymes, transcription factors, ion channels, neurotrophic factors, and postsynaptic scaffolding proteins. However, intracellular zinc concentration is tightly maintained at steady levels under natural physiological conditions. Dynamic changes in intracellular zinc concentration have only been detected in certain types of cells that are exposed to pathologic stimuli or upon receptor ligand binding. Unlike calcium, the ubiquitous signaling metal ion that can oscillate periodically and spontaneously in various cells, spontaneous zinc oscillations have never been reported. In this work, we made the novel observation that the developing neurons generated spontaneous and synchronous zinc spikes in primary hippocampal cultures using a fluorescent zinc sensor, FluoZin-3. Blocking of glutamate receptor-dependent calcium influx depleted the zinc spikes, suggesting that these zinc spikes were driven by the glutamate-mediated spontaneous neural excitability and calcium spikes that have been characterized in early developing neurons. Simultaneous imaging of calcium or pH together with zinc, we uncovered that a downward pH spike was evoked with each zinc spike and this transient cellular acidification occurred downstream of calcium spikes but upstream of zinc spikes. Our results suggest that spontaneous, synchronous zinc spikes were generated through calcium influx-induced cellular acidification, which liberates zinc from intracellular zinc binding ligands. Given that changes in zinc concentration can modulate activities of proteins essential for synapse maturation and neuronal differentiation, these zinc spikes might act as important signaling roles in neuronal development.


Assuntos
Potenciais de Ação/fisiologia , Sinalização do Cálcio/fisiologia , Hipocampo/fisiologia , Neurônios/fisiologia , Zinco/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Feminino , Ácido Glutâmico/farmacologia , Hipocampo/química , Hipocampo/efeitos dos fármacos , Neurônios/química , Neurônios/efeitos dos fármacos , Compostos Policíclicos/metabolismo , Compostos Policíclicos/farmacologia , Gravidez , Ratos , Ratos Sprague-Dawley , Zinco/análise
20.
Crit Care Med ; 49(10): 1739-1748, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115635

RESUMO

OBJECTIVES: The coronavirus disease 2019 pandemic has overwhelmed healthcare resources even in wealthy nations, necessitating rationing of limited resources without previously established crisis standards of care protocols. In Massachusetts, triage guidelines were designed based on acute illness and chronic life-limiting conditions. In this study, we sought to retrospectively validate this protocol to cohorts of critically ill patients from our hospital. DESIGN: We applied our hospital-adopted guidelines, which defined severe and major chronic conditions as those associated with a greater than 50% likelihood of 1- and 5-year mortality, respectively, to a critically ill patient population. We investigated mortality for the same intervals. SETTING: An urban safety-net hospital ICU. PATIENTS: All adults hospitalized during April of 2015 and April 2019 identified through a clinical database search. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 365 admitted patients, 15.89% had one or more defined chronic life-limiting conditions. These patients had higher 1-year (46.55% vs 13.68%; p < 0.01) and 5-year (50.00% vs 17.22%; p < 0.01) mortality rates than those without underlying conditions. Irrespective of classification of disease severity, patients with metastatic cancer, congestive heart failure, end-stage renal disease, and neurodegenerative disease had greater than 50% 1-year mortality, whereas patients with chronic lung disease and cirrhosis had less than 50% 1-year mortality. Observed 1- and 5-year mortality for cirrhosis, heart failure, and metastatic cancer were more variable when subdivided into severe and major categories. CONCLUSIONS: Patients with major and severe chronic medical conditions overall had 46.55% and 50.00% mortality at 1 and 5 years, respectively. However, mortality varied between conditions. Our findings appear to support a crisis standards protocol which focuses on acute illness severity and only considers underlying conditions carrying a greater than 50% predicted likelihood of 1-year mortality. Modifications to the chronic lung disease, congestive heart failure, and cirrhosis criteria should be refined if they are to be included in future models.


Assuntos
COVID-19/terapia , Intervenção em Crise/normas , Alocação de Recursos/métodos , Centros Médicos Acadêmicos/organização & administração , Centros Médicos Acadêmicos/estatística & dados numéricos , Adulto , COVID-19/epidemiologia , Intervenção em Crise/métodos , Intervenção em Crise/estatística & dados numéricos , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Alocação de Recursos/estatística & dados numéricos , Estudos Retrospectivos , Provedores de Redes de Segurança/organização & administração , Provedores de Redes de Segurança/estatística & dados numéricos , Padrão de Cuidado/normas , Padrão de Cuidado/estatística & dados numéricos , População Urbana/estatística & dados numéricos
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