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1.
Magn Reson Chem ; 61(3): 169-179, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36349476

RESUMO

The recently reported 19 F-detected dual-optimized inverted 1 JCC 1,n-ADEQUATE experiment and the previously reported 1 H-detected version have been modified to incorporate J-modulation, making it feasible to acquire all 1,1- and 1,n-ADEQUATE correlations as well as 1 JCC and n JCC homonuclear scalar couplings in a single experiment. The experiments are demonstrated using N,N-dimethylamino-2,5,6-trifluoro-3,4-phthalonitrile and N,N-dimethylamino-3,4-phthalonitrile.

2.
Magn Reson Chem ; 60(2): 210-220, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34469610

RESUMO

Modification of the recently reported 19 F-detected 1,1-ADEQUATE experiment that incorporates dual-optimization to selectively invert a wide range of 1 JCC correlations in a 1,n-ADEQUATE experiment is reported. Parameters for the dual-optimization segment of the pulse sequence were modified to accommodate the increased size of 1 JCC homonuclear coupling constants of poly- and perfluorinated molecules relative to protonated molecules to allow broadband inversion of the 1 JCC correlations. The observation and utility of isotope shifts are reported for the first time for 1,1- and 1,n-ADEQUATE correlations.

3.
Magn Reson Chem ; 59(6): 628-640, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33486827

RESUMO

Polyfluorinated and perfluorinated compounds in the environment are a growing health concern. 19 F-detected variants of commonly employed heteronuclear shift correlation experiments such as heteronuclear single quantum correlation (HSQC) and heteronuclear multiple bond correlation (HMBC) are available; 19 F-detected experiments that employ carbon-carbon homonuclear coupling, in contrast, have never been reported. Herein, we report the measurement of the 1 JCC and n JCC coupling constants of a simple perfluorinated phthalonitrile and the first demonstration of a 19 F-detected 1,1-ADEQUATE experiment.

4.
Phytochem Anal ; 24(6): 631-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23703884

RESUMO

INTRODUCTION: While the use of internal standard methodology for qNMR is a proven and reliable form of quantification, simplified alternative approaches are needed. Agilent's absolute intensity qNMR utility software is a valuable alternative that has not yet been subjected to validation in the peer-reviewed literature. OBJECTIVE: To provide validation of Agilent's absolute intensity qNMR method with a specific application to natural product quantification by measuring saccharide content in açaí materials. METHODS: In order to validate the method, calibration test samples of ibuprofen were prepared in DMSO-d6 at nine different concentrations and measured with (1) H-NMR. A minimum of 40 spectra were collected for each sample, and the absolute intensity utility was used for quantification. The same methodology was then applied to the açaí materials, creating triplicates for each of the materials and using 3-(trimethylsilyl)-1-propanesulphonic acid sodium salt in water-d2 as both the solvent and internal standard. (1) H-NMR spectra were collected, and the amounts of glucose, sucrose and fructose were determined using both the internal standard approach and the absolute intensity qNMR method. RESULTS: Applying the absolute intensity utility to the ibuprofen samples demonstrated a linear response (R(2) = 0.99943). For the açaí investigations, results obtained from the absolute intensity method were comparable to those obtained from the internal standard approach, with percentage differences ranging from 0.5-6.2%. CONCLUSION: This study demonstrates the accuracy, precision and reliability of Agilent's absolute intensity qNMR method. In addition, practical information is provided for assessing the saccharide contents of açaí materials.


Assuntos
Arecaceae/química , Frutose/análise , Glucose/análise , Ressonância Magnética Nuclear Biomolecular/métodos , Sacarose/análise , Ibuprofeno/análise , Reprodutibilidade dos Testes
5.
J Urol ; 187(1): 109-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22088340

RESUMO

PURPOSE: We evaluated our retrospective, single institution experience with high dose rate brachytherapy as monotherapy for intermediate risk prostate cancer. MATERIALS AND METHODS: Our cohort included 284 patients with intermediate risk prostate cancer, defined as clinical stage T2b/T2c, Gleason score 7 and/or prostate specific antigen 10 to 20 ng/ml, and 1-year minimum followup. Treatment was 2 high dose rate brachytherapy sessions at 3 fractions of 6.5 Gy each for a mean of 19 days. Prostate specific antigen failure was defined as nadir +2 ng/ml. RESULTS: Mean followup was 35.1 months (median 31.9). Actuarial 5-year cause specific survival and clinical local control were 100%, distant-metastasis-free survival 98.8% and biochemical disease-free survival 94.4%. Clinical stage predicted biochemical disease-free survival. For stage T2a or less 5-year biochemical disease-free survival was 95.1% vs 100% for stage T2b and 77.4% for T2c (p = 0.012). Percent positive biopsy cores and prostate specific antigen nadir were also predictive. International Prostate Symptom Score results remained stable and potency was maintained in 82.6% of patients at 2 years. Pads were used for the first time after brachytherapy in 22 patients (7.7%), mostly for grade 1 incontinence (occasionally or less per week). Excluding patients with prior transurethral prostatectomy, stroke or tremor 2.5% used pads for the first time after treatment. No patient had urethral stricture. Radiation Therapy Oncology Group grade 1 rectal toxicity developed in 12 patients (4.2%) but not beyond grade 1. CONCLUSIONS: High dose rate brachytherapy as monotherapy is safe and effective for patients with intermediate risk prostate cancer. We recommend caution for percent positive biopsy cores exceeding 75% or clinical stage T2c. Excluding such patients the 5-year biochemical disease-free survival rate was 97.5%.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores de Risco
6.
J Am Chem Soc ; 131(44): 15994-5, 2009 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-19845379

RESUMO

A new technique to deconvolute complex (1)H NMR spectra of small molecules has been developed that utilizes shape selective pulses to simultaneously decouple multiple protons. A limitation in the assignment of the relative configuration of small molecules is the ability to accurately obtain coupling constants. Other methods such as the E.COSY and the 2D J-resolved are available to obtain complicated coupling constants; the multiple homonuclear decoupling method (MDEC) described is a rapid and simple technique. Three examples of increasing spectral complexity, menthol, cholesteryl acetate and a C(16) fatty acid, demonstrate the utility of the technique. Increasing the experimental utility, the single pulse MDEC experiment can be incorporated in other 1D experiments, such as a 1D-TOCSY to solve specific problems.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Ésteres do Colesterol/química , Ácidos Graxos/química , Espectroscopia de Ressonância Magnética/instrumentação , Mentol/química , Métodos , Prótons
7.
Org Lett ; 4(19): 3293-6, 2002 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-12227772

RESUMO

Poecillastrin A (1), a new polyketide-derived macrolide lactam, was isolated from a deep-water collection of the marine sponge Poecillastra species. The structure of poecillastrin A (1) was assigned using NMR data acquired at 500 MHz with an inverse-detection cryogenic probe and at 800 MHz with a room-temperature probe.


Assuntos
Antineoplásicos/química , Lactamas/química , Macrolídeos/química , Espectroscopia de Ressonância Magnética , Poríferos/química , Animais , Temperatura Baixa , Estrutura Molecular
8.
J Prev Interv Community ; 42(1): 20-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24447156

RESUMO

For students with disabilities, the process of school inclusion often begins with a move from segregated settings into general education classrooms. School transitions can be stressful as students adjust to a new environment. This study examines the adjustment of 133 students with and without disabilities who moved from a school that served primarily students with disabilities into 23 public schools in a large urban school district in the Midwest. These students and 111 of their teachers and other school staff rated the degree that students felt they belonged in their new schools and the quality of their social interactions. Results show that students who experienced more positive and fewer negative social interactions with school staff had higher school belonging. Teachers accurately noted whether students felt they belonged in their new settings, but were not consistently able to identify student perceptions of negative social interactions with staff. Implications for inclusion and improving our educational system are explored.


Assuntos
Adaptação Psicológica , Crianças com Deficiência/educação , Crianças com Deficiência/psicologia , Docentes , Relações Interpessoais , Inclusão Escolar , Identificação Social , Adolescente , Coleta de Dados , Feminino , Humanos , Masculino , Meio-Oeste dos Estados Unidos , Grupo Associado , Ajustamento Social , Percepção Social , Inquéritos e Questionários
9.
J Prev Interv Community ; 42(1): 58-71, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24447159

RESUMO

The inclusion of students with disabilities is a process that requires collaboration among multiple individuals, with teachers, aides, parents, students, and school systems playing important roles in resolving student problems. In the current study, we examined data from 75 teachers concerning 126 students about problems that students with disabilities had following a transition from a school primarily serving students with disabilities to more inclusive schools. Reported problems were reviewed and five major themes emerged: academic, behavioral, mobility/accessibility, social, and transportation issues. Teachers typically resolved academic problems by working directly with the student or collaborating with school staff. Social problems were resolved through student and teacher initiatives. Behavioral, transportation, and mobility/accessibility problems were resolved through collaboration among many key school figures and family members. Implications for theory, research, and inclusive school practices related to academic curricula, resources, services, and architectural accommodations for students with disabilities are discussed.


Assuntos
Logro , Acessibilidade Arquitetônica , Negro ou Afro-Americano/educação , Negro ou Afro-Americano/psicologia , Crianças com Deficiência/educação , Crianças com Deficiência/psicologia , Hispânico ou Latino/educação , Hispânico ou Latino/psicologia , Inclusão Escolar , Comportamento Social , Meios de Transporte , População Urbana , Adolescente , Comportamento Cooperativo , Currículo , Coleta de Dados , Feminino , Humanos , Comunicação Interdisciplinar , Masculino , Meio-Oeste dos Estados Unidos , Resolução de Problemas , Pesquisa Qualitativa , Meio Social , Identificação Social
10.
Magn Reson Chem ; 42(3): 301-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14971014

RESUMO

Compensation of refocusing inefficiency in a gHMBC experiment by replacing the rectangular pi pulse with a pair of adiabatic pulses with synchronized inversion sweep (CRISIS) significantly improves the performance of the gHMBC experiment. The CRISIS-gHMBC experiment retains the pure absorptive shapes in F1 and hence results in better lineshape and higher resolution than the current versions of magnitude mode gHMBC spectra. When used as a broadband experiment, CRISIS-gHMBC, owing to better refocusing efficiency of the adiabatic pulse pairs, gives improved performance across the 13C spectral width. Moreover, it is shown that CRISIS-gHMBC is a robust and improved alternative and when used along with the IMPRESS (Improved Resolution using Symmetrically Shifted pulses) technique further increases the sensitivity and resolution without additional experimental time. The IMPRESS-CRISIS combination is demonstrated for broadband gHMBC and band-selective gHMBC experiments. The ICbs-gHMBC [IMPRESS-CRISIS-band-selective gHMBC] experiment is an attractive and better alternative to individual band-selective gHMBC.

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