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1.
J Prev Alzheimers Dis ; 11(3): 787-797, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706295

RESUMO

BACKGROUND: Subjective cognitive decline (SCD) is defined as an individual's perception of sustained cognitive decline compared to their normal state while still performing within boundaries for normal functioning. Demographic, psychosocial and medical factors have been linked to age-related cognitive decline, and Alzheimer's dementia (AD). However, their relation to risk for SCD remains unclear. This study aims to identify demographic factors, psychosocial and cardiovascular health associated with SCD within the Brain Health Registry (BHR) online cohort. METHODS: Participants aged 55+ (N=27,596) in the BHR self-reported SCD measured using the Everyday Cognition Scale (ECog) and medical conditions, depressive symptoms, body mass index, quality of sleep, health, family history of AD, years of education, race, ethnicity and gender. Multivariable linear regression was used to examine whether SCD was associated with demographic, psychosocial, and medical conditions. RESULTS: We found that advanced age, depressive symptoms, poorer sleep quality and poorer quality of health were positively associated with more self-reported SCD in all models. No race or ethnicity differences were found in association with SCD. Males who reported alcohol and tobacco use or underweight BMI had higher ECog scores compared with females. CONCLUSION: In addition to well-established risk factors for cognitive decline, such as age, our study consistently and robustly identified a strong association between psychosocial factors and self-reported cognitive decline in an online cohort. These findings provide further evidence that psychosocial health plays a pivotal role in comprehending the risk of SCD and early-stage cognitive ageing. Our findings emphasise the significance of psychosocial factors within the broader context of cardiovascular and demographic risk factors.


Assuntos
Disfunção Cognitiva , Depressão , Sistema de Registros , Humanos , Masculino , Feminino , Disfunção Cognitiva/epidemiologia , Pessoa de Meia-Idade , Idoso , Depressão/epidemiologia , Depressão/psicologia , Fatores de Risco , Autorrelato , Estudos de Coortes , Nível de Saúde
2.
Small ; 19(41): e2302289, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37310414

RESUMO

The field of photovoltaics is revolutionized in recent years by the development of two-dimensional (2D) type-II heterostructures. These heterostructures are made up of two different materials with different electronic properties, which allows for the capture of a broader spectrum of solar energy than traditional photovoltaic devices. In this study, the potential of vanadium (V)-doped WS2 is investigated, hereafter labeled V-WS2 , in combination with air-stable Bi2 O2 Se for use in high-performance photovoltaic devices. Various techniques are used to confirm the charge transfer of these heterostructures, including photoluminescence (PL) and Raman spectroscopy, along with Kelvin probe force microscopy (KPFM). The results show that the PL is quenched by 40%, 95%, and 97% for WS2 /Bi2 O2 Se, 0.4 at.% V-WS2 /Bi2 O2 Se, and 2 at.% V-WS2 /Bi2 O2 Se, respectively, indicating a superior charge transfer in V-WS2 /Bi2 O2 Se compared to pristine WS2 /Bi2 O2 Se. The exciton binding energies for WS2 /Bi2 O2 Se, 0.4 at.% V-WS2 /Bi2 O2 Se and 2 at.% V-WS2 /Bi2 O2 Se heterostructures are estimated to be ≈130, 100, and 80 meV, respectively, which is much lower than that for monolayer WS2 . These findings confirm that by incorporating V-doped WS2 , charge transfer in WS2 /Bi2 O2 Se heterostructures can be tuned, providing a novel light-harvesting technique for the development of the next generation of photovoltaic devices based on V-doped transition metal dichalcogenides (TMDCs)/Bi2 O2 Se.

3.
Nature ; 582(7811): 294-297, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32523118

RESUMO

The primary structural component of the bacterial cell wall is peptidoglycan, which is essential for viability and the synthesis of which is the target for crucial antibiotics1,2. Peptidoglycan is a single macromolecule made of glycan chains crosslinked by peptide side branches that surrounds the cell, acting as a constraint to internal turgor1,3. In Gram-positive bacteria, peptidoglycan is tens of nanometres thick, generally portrayed as a homogeneous structure that provides mechanical strength4-6. Here we applied atomic force microscopy7-12 to interrogate the morphologically distinct Staphylococcus aureus and Bacillus subtilis species, using live cells and purified peptidoglycan. The mature surface of live cells is characterized by a landscape of large (up to 60 nm in diameter), deep (up to 23 nm) pores constituting a disordered gel of peptidoglycan. The inner peptidoglycan surface, consisting of more nascent material, is much denser, with glycan strand spacing typically less than 7 nm. The inner surface architecture is location dependent; the cylinder of B. subtilis has dense circumferential orientation, while in S. aureus and division septa for both species, peptidoglycan is dense but randomly oriented. Revealing the molecular architecture of the cell envelope frames our understanding of its mechanical properties and role as the environmental interface13,14, providing information complementary to traditional structural biology approaches.


Assuntos
Bacillus subtilis/citologia , Bacillus subtilis/ultraestrutura , Parede Celular/química , Parede Celular/ultraestrutura , Microscopia de Força Atômica , Staphylococcus aureus/citologia , Staphylococcus aureus/ultraestrutura , Bacillus subtilis/química , Viabilidade Microbiana , Peptidoglicano/química , Peptidoglicano/isolamento & purificação , Peptidoglicano/ultraestrutura , Staphylococcus aureus/química
5.
Am J Gastroenterol ; 91(4): 792-4, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8677953

RESUMO

Extrapulmonary small cell carcinoma has been reported from multiple sites, including the gallbladder. Small cell carcinoma of the gallbladder is a very rare tumor, found usually in elderly women and associated with cholelithiasis. It carries a grave prognosis, metastasizing early and causing death shortly after diagnosis. Treatment of metastatic disease with two different chemotherapeutic regimens has been shown to improve survival. To the best of our knowledge, this tumor has not been previously reported in a black individual, or in any subject less than 49 yr or more than 79 yr old. We report two cases: one is the first black and youngest reported case. The second is the oldest person reported with this rare malignancy. Radiological studies such as ultrasound and CT scan were useful in evaluating tumor spread and follow-up.


Assuntos
Carcinoma de Células Pequenas/epidemiologia , Neoplasias da Vesícula Biliar/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Pequenas/diagnóstico , Carcinoma de Células Pequenas/secundário , Carcinoma de Células Pequenas/terapia , Feminino , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/terapia , Humanos , Masculino , Prognóstico
7.
Clin Nucl Med ; 18(10): 852-7, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8242977

RESUMO

Several methods are available for performing radionuclide stress myocardial perfusion studies. All of these methods require two separate acquisition and processing iterations, which is time-consuming and inconvenient for the patient. The authors introduce a new method using the "three window technique" that they developed to perform simultaneous dual-isotope imaging for stress myocardial perfusion studies. In addition to Tl-201 and Tc-99m windows centered at 70 KeV and 140 KeV, respectively, a third window centered at 105 KeV, representing scattered radioactivity from Tc-99m, is established. By subtracting the radioactivity in the third window from the radioactivity in the Tl-201 window, "crosstalk" interference is significantly reduced. The simultaneous dual-isotope imaging method acquires and processes resting and stress myocardial perfusion images simultaneously. It halves imaging time and doubles patient throughput, improves scheduling flexibility, and reduces patient waiting time and discomfort.


Assuntos
Coração/diagnóstico por imagem , Esforço Físico/fisiologia , Tecnécio Tc 99m Sestamibi , Radioisótopos de Tálio , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Orthop Sports Phys Ther ; 3(3): 108-20, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-18810134

RESUMO

A systematic approach is presented for evaluating the shoulder complex in athletes. The evaluation is divided into two parts: the subjective and objective examinations. The evaluation will determine the severity of the injury, the irritability of injury, and the structural involvement, and provide objective data for designing a comprehensive program of rehabilitation. J Orthop Sports Phys Ther 1982;3(3):108-120.

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