Search results for "resonance spectroscopy"
showing 10 items of 1478 documents
Antikonvulsiva, 1. Mitt. Thiocarbamoylbutyroguanamine
1986
Durch Anlagerung von Butyroguanamin (1) an die Isothiocyanate 2a-c sind die Thiocarbamoylbutyroguanamine 3a-c zuganglich. Auf dem Wege der Acylierung von 3 sind unsymmetrisch substituierte Butyroguanamine 4 erhaltlich. Unter den neu entwickelten Verbindungen zeichnet sich insbesondere 3c durch antikonvulsive, fungizide und die Magensauresekretion hemmende Wirkungen aus. Anticonvulsivic Agents, I: Thiocarbamoylbutyroguanamines The thiocarbamoylbutyroguanamines 3a-c are accessible by addition of butyroguanamine (1) to the isothiocyanates 2a-c. Unsymmetrically substituted butyroguanamines 4 are obtainable by acylation of 3. Among the newly prepared compounds, 3c in particular exhibits anticonv…
The identification of vicinally substituted cyclohexane isomers in their mixtures by 1H and 13C NMR spectroscopy.
2000
The radical addition reactions of organobromine compounds, XBr (X = CH2COOMe, PhCH2, CHBr2 and CCl3) with cyclohexene afforded mixtures of cis/trans isomer pairs of 1-X-2-Br-cyclohexanes. In addition to benzyl benzoyloxy derivatives are formed also, when benzoyl peroxide is used as an initiator. Owing to the great difficulties in separating these cis/trans isomer pairs, they are identified directly in their mixtures by NMR spectroscopy. In addition to one-dimensional (ID) 1H, proton decoupled 13C and DEPT-135, also two-dimensional (2D) 13C-13C INADEQUATE as well as 1H-13C HMQC experiments have been used in assigning the signals of each compound in their mixtures. The identification of each …
Follicular adenomas exhibit a unique metabolic profile. ¹H NMR studies of thyroid lesions.
2013
Thyroid cancer is the most common endocrine malignancy. However, more than 90% of thyroid nodules are benign. It remains unclear whether thyroid carcinoma arises from preexisting benign nodules. Metabolomics can provide valuable and comprehensive information about low molecular weight compounds present in living systems and further our understanding of the biology regulating pathological processes. Herein, we applied ¹H NMR-based metabolic profiling to identify the metabolites present in aqueous tissue extracts of healthy thyroid tissue (H), non-neoplastic nodules (NN), follicular adenomas (FA) and malignant thyroid cancer (TC) as an alternative way of investigating cancer lesions. Multivar…
Coordination properties of adenosine-5'-monophosphate and related ligands towards Me2Sn(IV)2+ in aqueous solution.
2002
Abstract The coordination of Me 2 Sn(IV) 2+ to adenosine-5′-monophosphate (AMP) and the related compounds d -ribose-5-phosphate (R5P), d -glucose-1-phosphate (G1P) and d -glucose-6-phosphate (G6P) in aqueous solution was investigated by means of potentiometric titration, and 1 H-, 31 P-NMR and Mossbauer spectroscopic methods in the pH range 2–11 ( I =0.1 M NaClO 4 , 298 K). The complex of AMP and Me 2 Sn(IV) 2+ precipitated at low pH was characterised by elemental analysis, FT-IR and Mossbauer spectroscopic methods. From a comparison of the p K values obtained in the presence and absence of metal ion and the stability constants for the different systems, the coordination of {N} is excluded,…
Flying insects: model systems in exercise physiology
1996
Insect flight is the most energy-demanding exercise known. It requires very effective coupling of adenosine triphosphate (ATP) hydrolysis and regeneration in the working flight muscles.31P nuclear magnetic resonance (NMR) spectroscopy of locust flight muscle in vivo has shown that flight causes only a small decrease in the content of ATP, whereas the free concentrations of inorganic phosphate (P i ), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) were estimated to increase by about 3-, 5- and 27-fold, respectively. These metabolites are potent activators of glycogen phosphorylase and phosphofructokinase (PFK). Activation of glycolysis by AMP and P i is reinforced synergistica…
Application of 1H NMR-based serum metabolomic studies for monitoring female patients with rheumatoid arthritis
2015
AbstractRheumatoid arthritis is a chronic autoimmune-based inflammatory disease that leads to progressive joint degeneration, disability, and an increased risk of cardiovascular complications, which is the main cause of mortality in this population of patients. Although several biomarkers are routinely used in the management of rheumatoid arthritis, there is a high demand for novel biomarkers to further improve the early diagnosis of rheumatoid arthritis, stratification of patients, and the prediction of a better response to a specific therapy.In this study, the metabolomics approach was used to provide relevant biomarkers to improve diagnostic accuracy, define prognosis and predict and mon…
A metabolomic approach to dry eye disorders. The role of oral supplements with antioxidants and omega 3 fatty acids.
2014
Purpose We used nuclear magnetic resonance spectroscopy of hydrogen-1 nuclei (1H NMR S) to analyze the metabolic profile of reflex tears from patients with dry eye disorders. Methods We performed a prospective case-control study involving 90 participants: 55 patients diagnosed with dry eye syndrome (DESG) and 35 healthy subjects (control group, CG). From the DESG, two subgroups were formed: mild DES (n=22) and moderate DES (n=33). Participants were prescribed an oral nutraceutic supplementation containing antioxidants and essential polyunsaturated fatty acids to be taken as three capsules per day for 3 months. Reflex tears (20–30 µl) were collected from the tear meniscus of both eyes of eac…
Neurochemical alterations in women with borderline personality disorder and comorbid attention-deficit hyperactivity disorder
2010
Borderline personality disorder (BPD) is associated with structural and functional brain changes. Recent models and findings refer to alterations of glutamate and total N-acetylaspartate (tNAA) in this condition.Absolute quantities of tNAA, creatine, glutamate, glutamine, myoinositol and total choline were measured using 3 Tesla magnetic resonance spectroscopy of the left anterior cingulate cortex and the left cerebellum in 14 unmedicated women with BPD and comorbid attention-deficit hyperactivity disorder (ADHD) and 18 healthy women. Both groups were matched with respect to age, education and premorbid intelligence.In the anterior cingulate, we found significantly higher tNAA and glutamate…
MRI studies after treatment of brain tumors in childhood and adolescence
1986
Forty-seven children and adolescents with brain tumors were examined by magnetic resonance imaging (MRI) after tumor resection. The typical changes and complications after surgery and chemotherapy, as well as the corresponding MRI findings, are discussed. Typical examples of boundary-layer lesions, tumor recurrences, hydrocephalus, porencephalic cysts, and hygromas are given.
Cardiac Magnetic Resonance with Delayed Enhancement of the Right Ventricle in patients with Left Ventricle primary involvement: diagnosis and evaluat…
2020
: Cardiac Magnetic Resonance (CMR) allows an accurate Right Ventricle (RV) assessment that could be of great relevance in diseases causing inflammation or fibrosis. The aim of this study was to evaluate the concomitant involvement of the RV in patients with delayed enhancement (DE) of the Left Ventricle (LV-DE) using CMR. We retrospectively enrolled 95 (male n. 66; age 55±18years; BMI 26±5kg/m2) consecutive patients with LV-DE who underwent a CMR (Achieva 1.5 T, Philips) for different indications: post-ischemic dilated cardiopathy (PDM), hypertrophic cardiomyopathy (HCM), myocardial infarction (MI), myocarditis/pericarditis (MP) and congenital heart disease (CD). We assessed the presence an…