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1.
Molecules ; 25(20)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050240

RESUMO

Studying disease models at the molecular level is vital for drug development in order to improve treatment and prevent a wide range of human pathologies. Microbial infections are still a major challenge because pathogens rapidly and continually evolve developing drug resistance. Cancer cells also change genetically, and current therapeutic techniques may be (or may become) ineffective in many cases. The pathology of many neurological diseases remains an enigma, and the exact etiology and underlying mechanisms are still largely unknown. Viral infections spread and develop much more quickly than does the corresponding research needed to prevent and combat these infections; the present and most relevant outbreak of SARS-CoV-2, which originated in Wuhan, China, illustrates the critical and immediate need to improve drug design and development techniques. Modern day drug discovery is a time-consuming, expensive process. Each new drug takes in excess of 10 years to develop and costs on average more than a billion US dollars. This demonstrates the need of a complete redesign or novel strategies. Nuclear Magnetic Resonance (NMR) has played a critical role in drug discovery ever since its introduction several decades ago. In just three decades, NMR has become a "gold standard" platform technology in medical and pharmacology studies. In this review, we present the major applications of NMR spectroscopy in medical drug discovery and development. The basic concepts, theories, and applications of the most commonly used NMR techniques are presented. We also summarize the advantages and limitations of the primary NMR methods in drug development.


Assuntos
Desenho de Fármacos , Descoberta de Drogas/métodos , Espectroscopia de Ressonância Magnética/métodos , Humanos
3.
PLoS One ; 15(8): e0238316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866201

RESUMO

BACKGROUND: Perinatally HIV-infected children on anti-retroviral treatment (ART) are reported to have metabolic abnormalities such as dyslipidemia, lipodystrophy, and insulin resistance which potentially increase the risk of diabetes, kidney, liver and cardiovascular disease. OBJECTIVE: To elucidate HIV-mediated metabolic complications that sustain even during ART in perinatally HIV-infected children. METHOD: We have carried out metabolic profiling of the plasma of treatment-naïve and ART-suppressed perinatally HIV-infected children and uninfected controls using 1H nuclear magnetic resonance (NMR) spectroscopy followed by statistical analysis and annotation. RESULT: Validated multivariate analysis showed clear distinction among our study groups. Our results showed elevated levels of lactate, glucose, phosphoenolpyruvic acid, propionic acid, 2-ketobutyric acid and tricarboxylic acid (TCA) cycle metabolites in untreated HIV-infected children compared to uninfected controls. ART normalized the levels of several metabolites, however the level of lactate, phosphoenolpyruvic acid, oxoglutaric acid, oxaloacetic acid, myoinositol and glutamine remained upregulated despite ART in HIV-infected children. Pathway analysis revealed perturbed propanoate metabolism, amino acid metabolism, glycolysis and TCA cycle in untreated and ART-suppressed HIV-infected children. CONCLUSION: Developing therapeutic strategies targeting metabolic abnormalities may be beneficial for preventing diabetes, cardiovascular disease or other associated complications in perinatally HIV-infected children.


Assuntos
Infecções por HIV/metabolismo , Plasma/metabolismo , Antirretrovirais/uso terapêutico , Criança , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Metaboloma/fisiologia , Metabolômica/métodos , Projetos Piloto , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
4.
Medicine (Baltimore) ; 99(36): e20755, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32898989

RESUMO

Ga-PSMA-11 positron emission computed tomography /computed tomography (PET/CT) is more sensitive than magnetic resonance imaging (MRI) in detecting prostate cancer (PCa). We evaluated the value of Ga-PSMA-11 PET/CT with MRI in treatment-naive PCa.This retrospective study was approved by the hospital ethics committee. The MRI and Ga-PSMA-11 PET/CT imaging data of 63 cases of highly suspected PCa were enrolled in this study. The SUVmax and apparent diffusion coefficient (ADC), and their ratio, were assessed as diagnostic markers to distinguish PCa from benign disease.There were 107 prostate lesions detected in 63 cases. Forty cases with 64 malignant primary lesions were confirmed PCa, whereas 23 cases had 43 benign lesions. PSMA-avid lesions correlated with hypointense signal on ADC maps and hyperintense signal on diffusion-weighted imaging. The ADC of PCa was lower than that of benign lesions, and SUVmax and SUVmax/ADC of PCa was higher than that of benign lesions (P < .01). ADC had significant negative correlation with Gleason score (GS) and SUVmax, SUVmax, and SUVmax/ADC positively correlated with GS. From ROC analysis, we established cutoff values of ADC, SUVmax, and SUVmax/ADC at 1.02 × 10mm/s, 11.72, and 12.35, respectively, to differentiate PCa from benign lesions. The sensitivity, specificity, and AUC were 90.6%, 58.1%, and 0.816 for ADC, 67.2%, 97.7%, and 0.905 for SUVmax, and 81.2%, 88.4%, and 0.929 for SUVmax/ADC, respectively.Ga-PSMA-11 PET/CT combined with MRI offers higher diagnostic efficacy in the detection of PCa than either modality alone.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Antígeno Prostático Específico/análise , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/diagnóstico por imagem , Estudos Retrospectivos
5.
Proc Natl Acad Sci U S A ; 117(37): 23096-23105, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868434

RESUMO

The ß2-adrenergic receptor (ß2AR) is a prototypical G protein-coupled receptor (GPCR) that preferentially couples to the stimulatory G protein Gs and stimulates cAMP formation. Functional studies have shown that the ß2AR also couples to inhibitory G protein Gi, activation of which inhibits cAMP formation [R. P. Xiao, Sci. STKE 2001, re15 (2001)]. A crystal structure of the ß2AR-Gs complex revealed the interaction interface of ß2AR-Gs and structural changes upon complex formation [S. G. Rasmussen et al., Nature 477, 549-555 (2011)], yet, the dynamic process of the ß2AR signaling through Gs and its preferential coupling to Gs over Gi is still not fully understood. Here, we utilize solution nuclear magnetic resonance (NMR) spectroscopy and supporting molecular dynamics (MD) simulations to monitor the conformational changes in the G protein coupling interface of the ß2AR in response to the full agonist BI-167107 and Gs and Gi1 These results show that BI-167107 stabilizes conformational changes in four transmembrane segments (TM4, TM5, TM6, and TM7) prior to coupling to a G protein, and that the agonist-bound receptor conformation is different from the G protein coupled state. While most of the conformational changes observed in the ß2AR are qualitatively the same for Gs and Gi1, we detected distinct differences between the ß2AR-Gs and the ß2AR-Gi1 complex in intracellular loop 2 (ICL2). Interactions with ICL2 are essential for activation of Gs These differences between the ß2AR-Gs and ß2AR-Gi1 complexes in ICL2 may be key determinants for G protein coupling selectivity.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Benzoxazinas/farmacologia , Sítios de Ligação/fisiologia , Proteínas de Ligação ao GTP/metabolismo , Humanos , Espectroscopia de Ressonância Magnética/métodos , Simulação de Dinâmica Molecular , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
6.
Radiología (Madr., Ed. impr.) ; 62(4): 252-265, jul.-ago. 2020. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-ET6-355

RESUMO

En mujeres con alto riesgo de padecer cáncer de mama, la detección precoz tiene un importante papel. Debido a la alta incidencia de cáncer mamario y a edades más tempranas que en la población general, se recomienda que el cribado comience en edad más joven, y existe amplia evidencia de que la resonancia magnética es la herramienta diagnóstica más sensible: las principales guías americanas y europeas coinciden en la recomendación de realizar resonancia magnética anual (con mamografía anual suplementaria) como modalidad óptima de cribado. No obstante, no hay un total consenso actual entre las guías sobre algunos subgrupos de pacientes a incluir en la recomendación de cribado con resonancia magnética. El objetivo de esta primera parte de nuestro trabajo es, mediante una revisión de la bibliografía, explicar y valorar las ventajas que este tipo de cribado con resonancia magnética proporciona respecto al cribado solo con mamografía, como son: mayor detección de cánceres de menor tamaño y con menor afectación ganglionar asociada y una reducción de los cánceres de intervalo, lo que puede tener repercusión en supervivencia y mortalidad, con efectos comparables a otras medidas de prevención. Pero, a su vez, también queremos reflejar los inconvenientes que el cribado con resonancia magnética conlleva, y que dificultan su aplicabilidad


Screening plays an important role in women with a high risk of breast cancer. Given this population's high incidence of breast cancer and younger age of onset compared to the general population, it is recommended that screening starts earlier. There is ample evidence that magnetic resonance imaging (MRI) is the most sensitive diagnostic tool, and American and the European guidelines both recommend annual MRI screening (with supplementary annual mammography) as the optimum screening modality. Nevertheless, the current guidelines do not totally agree about the recommendations for MRI screening in some subgroups of patients. The first part of this article on screening in women with increased risk of breast cancer reviews the literature to explain and evaluate the advantages of MRI screening compared to screening with mammography alone: increased detection of smaller cancers with less associated lymph node involvement and a reduction in the rate of interval cancers, which can have an impact on survival and mortality (with comparable effects to other preventative measures). At the same time, however, we would like to reflect on the drawbacks of MRI screening that affect its applicability


Assuntos
Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Programas de Triagem Diagnóstica , Espectroscopia de Ressonância Magnética/métodos , Neoplasias da Mama/epidemiologia , Diagnóstico Precoce , Espectroscopia de Ressonância Magnética/efeitos adversos , Mamografia/métodos , Mamografia/tendências , Fatores de Risco , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/prevenção & controle
7.
Yakugaku Zasshi ; 140(8): 1063-1069, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32741864

RESUMO

Quantitative NMR (qNMR) has been developed as an absolute quantitation method to determine the purity or content of organic compounds including marker compounds in crude drugs. The "qNMR test" has been introduced into the crude-drug section of the Japanese Pharmacopoeia (JP) for determining the purity of reagents used for the assay in the JP. In Supplement II to the JP 17th edition published in June 2019, fifteen compounds adopted qNMR test were listed as the reagents for the assay. To establish the "qNMR test" in the crude drug section of the JP, there were several problems to be solved. Previously, we reported that the handling impurity signals from reference substances and targeted marker compounds, chemical shifts of reference substances, and peak unity of signals of targeted marker compounds are important factors to conduct qNMR measurements with intended accuracy. In this study, we investigated that the hygroscopicity of reagents could cause the changes in the compounds' purity depending on increasing their water content. Twenty-one standard products used for the crude-drug test in JP were examined by water sorption-desorption analysis, and ginsenosides and saikosaponins were found to be hygroscopic. To prepare a sample solution of saikosaponin b2 for qNMR analysis, samples need to be maintained for 18 h at 25°C and 76% relative humidity; further, samples need to be weighed at the same humidity for the qNMR analysis.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Higroscópicos/química , Higroscópicos/normas , Indicadores e Reagentes/normas , Espectroscopia de Ressonância Magnética/métodos , Farmacopeias como Assunto/normas , Ginsenosídeos/química , Ginsenosídeos/normas , Umidade , Japão , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácido Oleanólico/normas , Psicoterapia Breve , Saponinas/química , Saponinas/normas , Temperatura , Água/análise
8.
Nat Commun ; 11(1): 3840, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737293

RESUMO

Currently, human magnetic resonance (MR) examinations are becoming highly specialized with a pre-defined and often relatively small target in the body. Conventionally, clinical MR equipment is designed to be universal that compromises its efficiency for small targets. Here, we present a concept for targeted clinical magnetic resonance imaging (MRI), which can be directly integrated into the existing clinical MR systems, and demonstrate its feasibility for breast imaging. The concept comprises spatial redistribution and passive focusing of the radiofrequency magnetic flux with the aid of an artificial resonator to maximize the efficiency of a conventional MR system for the area of interest. The approach offers the prospect of a targeted MRI and brings novel opportunities for high quality specialized MR examinations within any existing MR system.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Cerâmica/efeitos da radiação , Espectroscopia Dielétrica/métodos , Imagem por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Adulto , Cerâmica/química , Espectroscopia Dielétrica/instrumentação , Radiação Eletromagnética , Desenho de Equipamento , Feminino , Voluntários Saudáveis , Humanos , Imagem por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Razão Sinal-Ruído
9.
J Nat Med ; 74(4): 811-818, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32705519

RESUMO

Investigation of the dried whole plants of Artemisia annua led to the isolation of two new sesquiterpenes, artemanins A (1) and B (2), along with twenty-nine known compounds. The structures of the new compounds were elucidated by spectroscopic and chemical means.


Assuntos
Artemisia annua/química , Espectroscopia de Ressonância Magnética/métodos , Plantas/química , Sesquiterpenos/química , Estrutura Molecular
10.
Nucleic Acids Res ; 48(13): 7041-7051, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32678885

RESUMO

Z-DNA is known to be a left-handed alternative form of DNA and has important biological roles as well as being related to cancer and other genetic diseases. It is therefore important to investigate Z-DNA structure and related biological events in living cells. However, the development of molecular probes for the observation of Z-DNA structures inside living cells has not yet been realized. Here, we have succeeded in developing site-specific trifluoromethyl oligonucleotide DNA by incorporation of 8-trifluoromethyl-2'-deoxyguanosine (FG). 2D NMR strongly suggested that FG adopted a syn conformation. Trifluoromethyl oligonucleotides dramatically stabilized Z-DNA, even under physiological salt concentrations. Furthermore, the trifluoromethyl DNA can be used to directly observe Z-form DNA structure and interaction of DNA with proteins in vitro, as well as in living human cells by19F NMR spectroscopy for the first time. These results provide valuable information to allow understanding of the structure and function of Z-DNA.


Assuntos
DNA Forma Z/análise , Desoxiguanosina/química , Espectroscopia de Ressonância Magnética/métodos , Oligonucleotídeos/química , Clonagem Molecular , Escherichia coli/genética , Células HeLa , Humanos , Metanol/análogos & derivados , Metanol/química
11.
Int J Mol Sci ; 21(14)2020 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-32664570

RESUMO

A dodecadepsipeptide valinomycin (VLM) has been most recently reported to be a potential anti-coronavirus drug that could be efficiently produced on a large scale. It is thus of importance to study solid-phase forms of VLM in order to be able to ensure its polymorphic purity in drug formulations. The previously available solid-state NMR (SSNMR) data are combined with the plane-wave DFT computations in the NMR crystallography framework. Structural/spectroscopical predictions (the PBE functional/GIPAW method) are obtained to characterize four polymorphs of VLM. Interactions which confer a conformational stability to VLM molecules in these crystalline forms are described in detail. The way how various structural factors affect the values of SSNMR parameters is thoroughly analyzed, and several SSNMR markers of the respective VLM polymorphs are identified. The markers are connected to hydrogen bonding effects upon the corresponding (13C/15N/1H) isotropic chemical shifts of (CO, Namid, Hamid, Hα) VLM backbone nuclei. These results are expected to be crucial for polymorph control of VLM and in probing its interactions in dosage forms.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Valinomicina/química , Betacoronavirus/química , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Isótopos de Carbono/química , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Cristalografia , Ligação de Hidrogênio , Isótopos de Nitrogênio/química , Pandemias , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Valinomicina/metabolismo
12.
Food Chem ; 332: 127339, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32659697

RESUMO

Non-targeted NMR-based approach has received great attention as a rapid method for food product authenticity assessment. The availability of a database containing many comparable NMR spectra produced by different spectrometers is crucial to develop functional classifiers able to discriminate rapidly the commodity class of a given food product. Nevertheless, variability in spectrometer features may hamper the production of comparable spectra due to inherent variations in signal resolution. In this paper, we report on the development of a class-discrimination model for grape juice authentication by application of non-targeted NMR spectroscopy. Different approaches for the pre-treatment of data will be described along with details about the model validation. The developed model performed excellently (95.4-100% correct predictions) even when it was tested against 650 spectra produced by 65 spectrometers with different configurations (magnetic field strength, manufacturer, age). This study may boost the use of non-targeted NMR methods for food control.


Assuntos
Análise de Alimentos/métodos , Qualidade dos Alimentos , Campos Magnéticos , Espectroscopia de Ressonância Magnética/métodos , Bases de Dados Factuais , Sucos de Frutas e Vegetais/análise , Vitis/química
13.
PLoS One ; 15(7): e0235057, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609725

RESUMO

The aim of the paper is two-fold. First, we show that structure finding with the PC algorithm can be inherently unstable and requires further operational constraints in order to consistently obtain models that are faithful to the data. We propose a methodology to stabilise the structure finding process, minimising both false positive and false negative error rates. This is demonstrated with synthetic data. Second, to apply the proposed structure finding methodology to a data set comprising single-voxel Magnetic Resonance Spectra of normal brain and three classes of brain tumours, to elucidate the associations between brain tumour types and a range of observed metabolites that are known to be relevant for their characterisation. The data set is bootstrapped in order to maximise the robustness of feature selection for nominated target variables. Specifically, Conditional Independence maps (CI-maps) built from the data and their derived Bayesian networks have been used. A Directed Acyclic Graph (DAG) is built from CI-maps, being a major challenge the minimization of errors in the graph structure. This work presents empirical evidence on how to reduce false positive errors via the False Discovery Rate, and how to identify appropriate parameter settings to improve the False Negative Reduction. In addition, several node ordering policies are investigated that transform the graph into a DAG. The obtained results show that ordering nodes by strength of mutual information can recover a representative DAG in a reasonable time, although a more accurate graph can be recovered using a random order of samples at the expense of increasing the computation time.


Assuntos
Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Algoritmos , Teorema de Bayes , Humanos , Metabolômica/métodos
14.
Nat Protoc ; 15(8): 2538-2567, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32681152

RESUMO

Metabolic profiling of biological samples provides important insights into multiple physiological and pathological processes but is hindered by a lack of automated annotation and standardized methods for structure elucidation of candidate disease biomarkers. Here we describe a system for identifying molecular species derived from nuclear magnetic resonance (NMR) spectroscopy-based metabolic phenotyping studies, with detailed information on sample preparation, data acquisition and data modeling. We provide eight different modular workflows to be followed in a recommended sequential order according to their level of difficulty. This multi-platform system involves the use of statistical spectroscopic tools such as Statistical Total Correlation Spectroscopy (STOCSY), Subset Optimization by Reference Matching (STORM) and Resolution-Enhanced (RED)-STORM to identify other signals in the NMR spectra relating to the same molecule. It also uses two-dimensional NMR spectroscopic analysis, separation and pre-concentration techniques, multiple hyphenated analytical platforms and data extraction from existing databases. The complete system, using all eight workflows, would take up to a month, as it includes multi-dimensional NMR experiments that require prolonged experiment times. However, easier identification cases using fewer steps would take 2 or 3 days. This approach to biomarker discovery is efficient and cost-effective and offers increased chemical space coverage of the metabolome, resulting in faster and more accurate assignment of NMR-generated biomarkers arising from metabolic phenotyping studies. It requires a basic understanding of MATLAB to use the statistical spectroscopic tools and analytical skills to perform solid phase extraction (SPE), liquid chromatography (LC) fraction collection, LC-NMR-mass spectroscopy and one-dimensional and two-dimensional NMR experiments.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Extração em Fase Sólida , Fluxo de Trabalho
15.
Transplantation ; 104(9): 1825-1831, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32675744

RESUMO

BACKGROUND: The lack of organs for kidney transplantation is a growing concern. Expansion in organ supply has been proposed through the use of organs after circulatory death (donation after circulatory death [DCD]). However, many DCD grafts are discarded because of long warm ischemia times, and the absence of reliable measure of kidney viability. P magnetic resonance imaging (pMRI) spectroscopy is a noninvasive method to detect high-energy phosphate metabolites, such as ATP. Thus, pMRI could predict kidney energy state, and its viability before transplantation. METHODS: To mimic DCD, pig kidneys underwent 0, 30, or 60 min of warm ischemia, before hypothermic machine perfusion. During the ex vivo perfusion, we assessed energy metabolites using pMRI. In addition, we performed Gadolinium perfusion sequences. Each sample underwent histopathological analyzing and scoring. Energy status and kidney perfusion were correlated with kidney injury. RESULTS: Using pMRI, we found that in pig kidney, ATP was rapidly generated in presence of oxygen (100 kPa), which remained stable up to 22 h. Warm ischemia (30 and 60 min) induced significant histological damages, delayed cortical and medullary Gadolinium elimination (perfusion), and reduced ATP levels, but not its precursors (AMP). Finally, ATP levels and kidney perfusion both inversely correlated with the severity of kidney histological injury. CONCLUSIONS: ATP levels, and kidney perfusion measurements using pMRI, are biomarkers of kidney injury after warm ischemia. Future work will define the role of pMRI in predicting kidney graft and patient's survival.


Assuntos
Trifosfato de Adenosina/metabolismo , Transplante de Rim , Rim/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Animais , Feminino , Perfusão , Suínos
16.
Neurology ; 95(7): e805-e814, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32591473

RESUMO

OBJECTIVE: To determine whether cervical cord levels of metabolites are associated with pain sensation after spinal cord injury (SCI) by performing magnetic resonance spectroscopy in patients with SCI with and without neuropathic pain (NP). METHODS: Cervical cord single-voxel spectroscopic data of 24 patients with SCI (14 with NP, 10 pain-free) and 21 healthy controls were acquired at C2/3 to investigate metabolite ratios associated with neuroinflammation (choline-containing compounds to myoinositol [tCho/mI]) and neurodegeneration (total N-acetylaspartate to myo-inositol [tNAA/mI]). NP levels were measured, and Spearman correlation tests assessed associations between metabolite levels, cord atrophy, and pinprick score. RESULTS: In patients with NP, tCho/mI levels were increased (p = 0.024) compared to pain-free patients and negatively related to cord atrophy (p = 0.006, r = 0.714). Better pinprick score was associated with higher tCho/mI levels (p = 0.032, r = 0.574). In pain-free patients, tCho/mI levels were not related to cord atrophy (p = 0.881, r = 0.055) or pinprick score (p = 0.676, r = 0.152). tNAA/mI levels were similar in both patient groups (p = 0.396) and were not associated with pinprick score in patients with NP (p = 0.405, r = 0.242) and pain-free patients (p = 0.117, r = 0.527). CONCLUSIONS: Neuroinflammatory metabolite levels (i.e., tCho/mI) were elevated in patients with NP, its magnitude being associated with less cord atrophy and greater pain sensation (e.g., pinprick score). This suggests that patients with NP have more residual spinal tissue and greater metabolite turnover than pain-free patients. Neurodegenerative metabolite levels (i.e., tNAA/mI) were associated with greater cord atrophy but unrelated to NP. Identifying the metabolic NP signature provides new NP treatment targets and could improve patient stratification in interventional trials. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that levels of magnetic resonance spectroscopy-identified metabolites of neuroinflammation were elevated in patients with SCI with NP compared to those without NP.


Assuntos
Medula Cervical/metabolismo , Inflamação/metabolismo , Neuralgia/metabolismo , Traumatismos da Medula Espinal/metabolismo , Adulto , Atrofia/patologia , Medula Cervical/patologia , Colina/metabolismo , Creatina/metabolismo , Feminino , Humanos , Inflamação/complicações , Inositol/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neuralgia/complicações , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/fisiopatologia
17.
PLoS One ; 15(6): e0234606, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32569331

RESUMO

Skeletal muscle dysfunction is a common complication and an important prognostic factor in patients with chronic obstructive pulmonary disease (COPD). It is associated with intrinsic muscular abnormalities of the lower extremities, but it is not known whether there is an easy way to predict its presence. Using a mouse model of chronic cigarette smoke exposure, we tested the hypothesis that magnetic resonance spectroscopy allows us to detect muscle bioenergetic deficit in early stages of lung disease. We employed this technique to evaluate the synthesis rate of adenosine triphosphate (ATP) and characterize concomitant mitochondrial dynamics patterns in the gastrocnemius muscle of emphysematous mice. The fibers type composition and citrate synthase (CtS) and cytochrome c oxidase subunit IV (COX4) enzymatic activities were evaluated. We found that the rate of ATP synthesis was reduced in the distal skeletal muscle of mice exposed to cigarette smoke. Emphysematous mice showed a significant reduction in body weight gain, in the cross-sectional area of the total fiber and in the COX4 to CtS activity ratio, due to a significant increase in CtS activity of the gastrocnemius muscle. Taken together, these data support the hypothesis that in the early stage of lung disease, we can detect a decrease in ATP synthesis in skeletal muscle, partly caused by high oxidative mitochondrial enzyme activity. These findings may be relevant to predict the presence of skeletal bioenergetic deficit in the early stage of lung disease besides placing the mitochondria as a potential therapeutic target for the treatment of COPD comorbidities.


Assuntos
Metabolismo Energético , Músculo Esquelético/fisiopatologia , Fumaça/efeitos adversos , Trifosfato de Adenosina/biossíntese , Trifosfato de Adenosina/deficiência , Animais , Pneumopatias/diagnóstico , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Tabaco/efeitos adversos
19.
J Chromatogr A ; 1623: 461130, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505268

RESUMO

The interactions and dynamic behavior of a select set of polar probe solutes have been investigated on three hydrophilic and polar commercial stationary phases using saturation transfer difference 1H nuclear magnetic resonance (STD-NMR) spectroscopy under magic angle spinning conditions. The stationary phases were equilibrated with a select set of polar solutes expected to show different interaction patterns in mixtures of deuterated acetonitrile and deuterium oxide, with ammonium acetate added to a total concentration that mimics typical eluent conditions for hydrophilic interaction chromatography (HILIC). The methylene groups of the stationary phases were selectively irradiated to saturate the ligand protons, at frequencies that minimized the overlaps with reporting protons in the test probes. During and after this radiation, the saturation rapidly spreads to all protons in the stationary phase by spin diffusion, and from those to probe protons in contact with the stationary phase. Probe protons that have been in close contact with the stationary phase and subsequently been released to the solution phase will have been more saturated due to a more efficient transfer of spin polarization by the nuclear Overhauser effect. They will therefore show a higher signal after processing of the data. Saturation transfers to protons in neutral and charged solutes could in some instances show clear orientation patterns of these solutes towards the stationary phases. The saturation profile of formamide and its N-methylated counterparts showed patterns that could be interpreted as oriented hydrogen bond interaction. From these studies, it is evident that the functional groups on the phase surface have a strong contribution to the selectivity in HILIC, and that the retention mechanism has a significant contribution from oriented interactions.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética/métodos , Ácido Benzoico/química , Dimetilformamida/química , Concentração de Íons de Hidrogênio , Compostos de Amônio Quaternário/química , Eletricidade Estática
20.
AAPS PharmSciTech ; 21(5): 136, 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32419122

RESUMO

The paclitaxel protein-bound particles for injectable suspension (marketed under the brand name Abraxane®) contains nanosized complexes of paclitaxel and albumin. The molecular interaction between paclitaxel and albumin within the higher-order nanostructure is analytically challenging to assess, as is any correlation of differences to differences in therapeutic effect. However, because the higher-order nanostructures may affect the paclitaxel release, a suitable in vitro assay to detect potential differences in paclitaxel release between comparator lots and products is desirable. Herein, solution NMR spectroscopy with a T2-filtering technique was developed to detect paclitaxel signal while suppressing albumin signals to follow the released paclitaxel in the NMR tube upon dilution. The non-invasive nature of NMR allows for precise measurement of a full range of dilution-induced drug release percentage from 14 to 92% without any sample extraction. The critical concentration of the drug product (DP) at 50% of release was 0.63 ± 0.04 mg/mL in PBS buffer. In addition, 2D diffusion ordered NMR spectroscopy (DOSY) results revealed that the released paclitaxel experiencing slightly slowed diffusion rates than free paclitaxel, which was attributed to paclitaxel in equilibrium with albumin-bound states. Collectively, the dilution-based NMR method offered an analytical approach to investigate physicochemical attributes of complex injectable products with minimal needed sample preparation and perturbation to nanoparticle formulation.


Assuntos
Albuminas/química , Composição de Medicamentos/métodos , Espectroscopia de Ressonância Magnética/métodos , Nanopartículas/química , Paclitaxel/administração & dosagem , Difusão , Paclitaxel/química , Tamanho da Partícula , Padrões de Referência , Solubilidade , Suspensões
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