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1.
medRxiv ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38343809

RESUMO

Defining the progression of blood biomarkers of Alzheimer's disease (AD) is essential for targeting treatments in patients most likely to benefit from early intervention. We delineated the temporal ordering of blood biomarkers a decade prior to the onset of AD symptoms in participants in the Baltimore Longitudinal Study of Aging. We show that increased astrocyte reactivity, assessed by elevated glial fibrillary acidic protein (GFAP) levels is an early event in the progression of blood biomarker changes in preclinical AD. In AD-converters who are initially cognitively unimpaired (N=158, 377 serial plasma samples), higher plasma GFAP levels are observed as early as 10-years prior to the onset of cognitive impairment due to incident AD compared to individuals who remain cognitively unimpaired (CU, N=160, 379 serial plasma samples). Plasma GFAP levels in AD-converters remain elevated 5-years prior to and coincident with the onset of cognitive impairment due to AD. In participants with neuropathologically confirmed AD, plasma GFAP levels are elevated relative to cognitively normal individuals and intermediate in those who remain cognitively unimpaired despite significant AD pathology (asymptomatic AD). Higher plasma GFAP levels at death are associated with greater severity of both neuritic plaques and neurofibrillary tangles. In the 5XFAD transgenic model of AD, we observed greater GFAP levels in the cortex and hippocampus of transgenic mice relative to wild-type prior to the development of cognitive impairment. Reactive astrocytosis, an established biological response to neuronal injury, may be an early initiator of AD pathogenesis and a promising therapeutic target.

3.
J Phys Chem B ; 126(12): 2420-2429, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35315675

RESUMO

Liquid-liquid extraction (LLE), the go-to process for a variety of chemical separations, is limited by spontaneous organic phase splitting upon sufficient solute loading, called third phase formation. In this study we explore the applicability of critical phenomena theory to gain insight into this deleterious phase behavior with the goal of improving separations efficiency and minimizing waste. A series of samples representative of rare earth purification were constructed to include each of one light and one heavy lanthanide (cerium and lutetium) paired with one of two common malonamide extractants (DMDOHEMA and DMDBTDMA). The resulting postextraction organic phases are chemically complex and often form rich hierarchical structures whose statics and dynamics near the critical point were probed herein with small-angle X-ray scattering and high-speed X-ray photon correlation spectroscopy. Despite their different extraction behaviors, all samples show remarkably similar critical behavior with exponents well described by classical critical point theory consistent with the 3D Ising model, where the critical behavior is characterized by fluctuations with a single diverging length scale. This unexpected result indicates a significant reduction in relevant chemical parameters at the critical point, indicating that the underlying behavior of phase transitions in LLE rely on far fewer variables than are generally assumed. The obtained scalar order parameter is attributed to the extractant fraction of the extractant/diluent mixture, revealing that other solution components and their respective concentrations simply shift the critical temperature but do not affect the nature of the critical fluctuations. These findings point to an opportunity to drastically simplify studies of liquid-liquid phase separation and phase diagram development in general while providing insights into LLE process improvement.

4.
Phys Rev Lett ; 125(12): 125504, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016761

RESUMO

The advent of high-speed x-ray photon correlation spectroscopy now allows the study of critical phenomena in fluids to much smaller length scales and over a wider range of temperatures than is possible with dynamic light scattering. We present an x-ray photon correlation spectroscopy study of critical fluctuation dynamics in a complex fluid typical of those used in liquid-liquid extraction (LLE) of ions, dodecane-DMDBTDMA with extracted aqueous Ce(NO_{3})_{3}. We observe good agreement with both static and dynamic scaling without the need for significant noncritical background corrections. Critical exponents agree with 3D Ising values, and the fluctuation dynamics are described by simple exponential relaxation. The form of the dynamic master curve deviates somewhat from the Kawasaki result, with a more abrupt transition between the critical and noncritical asymptotic behavior. The concepts of critical phenomena thus provide a quantitative framework for understanding the structure and dynamics of LLE systems and a path forward to new LLE processes.

5.
Health Promot Int ; 34(5): 992-1001, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085033

RESUMO

'Physical literacy' (PL) education-that is, teaching foundational skills, attitudes, behaviors and knowledge about lifelong involvements in physical activities, is an important aspect for health promotion among children. Universities have been playing a critical role by teaching future PL professionals. Additionally, various universities have offered university-based PL programming for neighborhood children as a way of public health promotion service and community engagement. However, this additional role of universities and the ways of promoting the quality of this type of health promotion service programming have not been investigated in the current research literature. Therefore, the purpose of this study was to identify the practicable strategies to enhance the quality of university-based PL programming for children from the perspectives of community stakeholders. Overall, 24 community stakeholders who held professional positions that are related to PL education participated in a 90-min focus group interview. This grounded theory study identified that university-based PL programming for children should be (i) inclusive, (ii) collaborative, (iii) welcoming and (iv) responsive. Practical suggestions and recommendations were also provided. This study has provided empirical knowledge to prioritize aspects for the future actions in planning and implementing university-based PL programming for children and informed for further cross-cultural comparisons amongst the perspectives of participants, university service providers and community stakeholders. The knowledge acquired from this research will also be translated to university service providers who operate similar type of health promotion service programming to the public.


Assuntos
Exercício Físico , Educação Física e Treinamento , Universidades/organização & administração , Adulto , Canadá , Criança , Saúde da Criança , Feminino , Grupos Focais , Promoção da Saúde/métodos , Humanos , Masculino , Pessoa de Meia-Idade
6.
Poult Sci ; 92(7): 1790-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23776266

RESUMO

To determine the ME and amino acid digestibility of 5 soybean meal (SBM) samples, a precision-fed rooster assay and a chick assay were conducted. The 5 samples were cold-pressed (extruded) soybean meals or solvent-extracted (defatted) soybean meal. Of the cold-pressed varieties (unheated), there was an ultra-low trypsin SBM, a low-trypsin SBM, and a heated and unheated commodity SBM. The solvent-extracted SBM was a heated commodity blend. The TME and AME values were compared between each category: cold-pressed and defatted, as well as between the 2 assays. Semipurified diets containing dextrose as the main energy source were formulated to meet the bird's nutrient requirements, with each diet containing a different SBM product. The TME rooster assay was a precision-fed rooster assay in which 5 birds per diet were fasted for 24 h, crop intubated with 35 g of the test diet containing 46.58% cold-pressed or defatted SBM, and excreta was then collected for 48 h. The total aromatic amino acids rooster assay followed the same protocol, but cecectomized birds were used. For the chick assay, 480 one-day-old chicks were fed a standard corn-SBM starter diet until 17 d of age, and on d 18, the chicks were allowed ad libitum access to the SB-dextrose diets. Excreta were collected on d 22, dried, ground, and analyzed for gross energy and CP to determine ME. The SBM samples that were genetically selected to have lower trypsin inhibitor levels and higher protein had higher ME values and increased amino acid digestibility than the commodity cold-pressed SBM samples. Genetic selection of soybeans for certain traits can have positive effects on the ME value and amino acid digestibility for roosters and chicks.


Assuntos
Aminoácidos/metabolismo , Galinhas/fisiologia , Digestão/fisiologia , Metabolismo Energético/fisiologia , Glycine max/química , Glycine max/genética , Aminoácidos/química , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Seleção Genética
7.
Ann Oncol ; 10(10): 1251-3, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10586346

RESUMO

BACKGROUND: Diarrhea is one of the most disturbing effects of chemotherapy, affecting quality of life on the one hand and limiting applicable doses on the other. Irinotecan (CPT-11) and 5-fluorouracil (5-FU) are associated with an elevated risk of developing severe diarrhea. Standard therapy consists of high-dose loperamide, but is associated with frequent failure. Other therapeutic regimens are still experimental. Endoscopic examination of a patient with severe loperamide-resistant diarrhea after CPT-11 chemotherapy revealed an inflammation of the ileo-coecal region. Oral therapy with the topical corticosteroid budesonide was immediately effective. This led to a phase I study of budesonide in CPT-11- and 5-FU-induced and loperamide-refractory diarrhea. PATIENTS AND METHODS: Fourteen patients with CPT-11- and seven patients with 5-FU-induced grade 3-4 (NCI/WHO) diarrhea and loperamide failure were enrolled in this study. All patients had metastatic colorectal cancer. RESULTS: In 86% of the CPT-11- and 57% of the 5-FU-treated patients with grade 3-4 diarrhea and loperamide failure, treatment with budesonide resulted in a reduction of diarrhea severity by at least two grades. CONCLUSIONS: The orally administered topical active steroid budesonide is highly effective in the therapy of loperamide-refractory chemotherapy (CPT-11 or 5-FU)-induced diarrhea.


Assuntos
Anti-Inflamatórios/uso terapêutico , Budesonida/uso terapêutico , Diarreia/tratamento farmacológico , Administração Oral , Administração Tópica , Idoso , Antineoplásicos Fitogênicos/efeitos adversos , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Diarreia/induzido quimicamente , Feminino , Fluoruracila/efeitos adversos , Glucocorticoides , Humanos , Irinotecano , Loperamida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Falha de Tratamento
8.
J Infus Chemother ; 6(3): 137-40, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9229325

RESUMO

To improve the therapeutic ratio of palliative chemotherapy in patients with metastatic colorectal and gastric cancer 5-fluorouracil (5-FU) was administered as weekly high-dose 24-hour continuous infusion in combination with leucovorin (LV) and interferon-alpha-2b (IFN) as biomodulating agents: Chemotherapy consisted of a weekly schedule of 500 mg/m2 leucovorin as a 2-hour infusion, followed by a 24-hour continuous infusion of 2500 mg/m2 5-FU. IFN was administered subcutaneously at a dose of 3 mio I.E. three times a week. In patients with gastric carcinoma, etoposide (VP) 100 mg/m2 as 30-minute bolus infusion was added. Eighty-five patients (colorectal: 55 points, gastric: 30 points) are evaluable for response, toxicity, and survival analysis. Colorectal: CP+PR: 19/55 (34.5%), NC: 25/55 (45.5%), PD: 11/55 (20.0%). Median duration of remission in months (90% confidence interval): 5.2 (3.1 to 9.2), median survival since the start of salvage chemotherapy: 13.9 months (12.3 to 20.1), from initial diagnosis of metastasis: 30.2 months (26.3 to 44.5). Gastric: CR: 8/30 (26.7%), PR: 14/30 (46.6), NC: 5/30 (16.7), PD: 3/30 (10.0%). Median duration of remission in months (90% confidence interval): 6.75 (1.5 to 16.2), median survival since start of chemotherapy: 15.1 months (90% confidence interval 11.8 to 20.3 months). Hematologic toxicity: hemoglobin: I: 20.0%, II: 10.0%, leukocytes: I: 13.3%, II: 33.3%, III: 16.6%, platelets: I: 10.0% and III: 3.3%. Hematologic toxicity was moderate to negligible, peripheral toxicity consisted mainly of tolerable stomatitis and diarrhea. Dose and schedule intensified weekly 5-FU combination therapy in metastatic colorectal and gastric cancer is highly active in terms of response and median survival time. Chemotherapy pretreated patients with colorectal cancer seem to have a substantial survival benefit with this salvage protocol.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/secundário , Fluoruracila/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/secundário , Adulto , Idoso , Antídotos/uso terapêutico , Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/mortalidade , Relação Dose-Resposta a Droga , Etoposídeo/uso terapêutico , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Infusões Intravenosas , Interferon-alfa/uso terapêutico , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
9.
J Cancer Res Clin Oncol ; 117 Suppl 4: S125-8, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1795000

RESUMO

The oxazaphosphorine analog ifosfamide (IFO) has demonstrated an increased therapeutic index in a variety of solid tumors and hematologic malignancies compared with its parent compound cyclophosphamide. A fractionated dose schedule over 5 days as continuous infusion in combination with the uroprotective agent sodium-2-mercapto-ethane-sulfonate (mesna) is considered to provide an improved therapeutic/toxic ratio. Stability data of IFO demonstrate long-term stability for use in disposable infusion pumps as outpatient treatment. In all, 52 patients with various malignancies were entered in a feasibility study to receive outpatient continuous infusion of IFO. All patients were required to have a subcutaneous venous port system implanted. The following drug combinations were used: IFO as single agent, IFO/mitoxantrone, IFO/carboplatinum/etoposide, IFO/etoposide/MTX, IFO/epirubicin. Mitoxantrone and epirubicin were given as continuous infusion together with IFO. Starting dose of IFO was between 1.6-2.0 g/m2/day x 5 and was increased in absence of major hematologic or peripheral toxicity. Mesna was given in combination with IFO as continuous infusion at a dose of 50% of that calculated for IFO. No renal, bladder or central nervous system toxicity was observed. In 247 courses of outpatient continuous ifosfamide infusion only few technical complications due to improper handling were documented.


Assuntos
Assistência Ambulatorial , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ifosfamida/administração & dosagem , Neoplasias/tratamento farmacológico , Adulto , Idoso , Carboplatina/administração & dosagem , Esquema de Medicação , Estabilidade de Medicamentos , Epirubicina/administração & dosagem , Etoposídeo/administração & dosagem , Estudos de Viabilidade , Feminino , Humanos , Bombas de Infusão Implantáveis , Infusões Intravenosas , Masculino , Mesna/administração & dosagem , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem
10.
Adv Exp Med Biol ; 244: 267-73, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3073661

RESUMO

58 patients with locally advanced or relapsed squamous cell head and neck cancer were treated on 5 consecutive days with DDP 20 mg/m2/d IV-push, followed by CF 100 mg/m2/d IV-bolus and Fura 400 mg/m2/d IV-push 60 minutes later. Treatment was recycled on day 22(-29), according to toxicity. CF was added to the widely used DDP/Fura combination, because recent studies showed enhancement of Fura-activity by CF. 45/58 patients had no prior therapy and 13/58 pts were relapsed after chemotherapy and/or radiation therapy. All patients were evaluable for toxicity and response. After 3 courses of induction chemotherapy 23/45 pts in the previously untreated group had a complete response (CR); 20/45 a partial response (PR), 2/45 were restaged as no change (CR + PR: 95%). Induction chemotherapy was followed by radical surgery and postoperative radiation therapy. In the pretreated group 4/13 pts had a complete response; 6/13 a partial response; no change in 3/13 pts. Median duration of remission (MDR) has not been reached in the primarily untreated group, whereas in pretreated patients the MDR was 3.8 months (range 2.3 - 11.7 months). Hematologic and gastrointestinal toxicity was substantial but manageable and therapy was performed on an outpatient basis. The combination of DDP, CF and Fura has high activity in untreated and pretreated head and neck cancer patients. The obtained results are comparable to the widely used DDP/Fura continuous infusion regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/patologia , Cisplatino/administração & dosagem , Ensaios Clínicos como Assunto , Esquema de Medicação , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
11.
Cathet Cardiovasc Diagn ; 4(2): 225-8, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-667925

RESUMO

Hemodynamic pressure measurements obtained during cardiac catheterization studies are calibrated to an arbitrary level where the pressure is considered zero. Despite the fundamental nature of the zero reference level, there is no standardized method for determination of "zero reference." A horizontal metal rod has been constructed to be level with the pressure transducer domes. With lateral radiographic viewing, the metal rod is adjusted to be level with the junction of the inferior vena cava and the right atrium. The technique is rapid, reliable, without risk and allows accurate comparison of hemodynamic data between patients and in the same patient longitudinally.


Assuntos
Pressão Sanguínea , Cateterismo Cardíaco/instrumentação , Cateterismo Cardíaco/métodos , Criança , Humanos
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