Real time band selective F1 -decoupled proton NMR for the demixing of overlay spectra of chiral molecules.

The small chemical shift dispersion and complex multiplicity pattern in proton NMR limit quantifications, for instance the determination of enantiomeric excess (ee) for an enantiomeric mixture. Herein, we present a simple proton-proton correlation experiment with band selective homonuclear (BASH) decoupling in both F1 and F2 dimensions, for the removal of scalar and residual dipolar couplings to provide collapsed singlet for each chemical site. The method has been demonstrated to separate the severely overlapped spectra of enantiomers using both chiral isotropic and anisotropic phases as well as a small biomolecule, particularly for the diastereotopic protons and also for the determination of ee. Copyright © 2016 John Wiley & Sons, Ltd.

NMR based serum metabolomics reveals a distinctive signature in patients with Lupus Nephritis.

Management of patient with Lupus Nephritis (LN) continues to remain a challenge for the treating physicians because of considerable morbidity and even mortality. The search of biomarkers in serum and urine is a focus of researchers to unravel new targets for therapy. In the present study, the utility of NMR-based serum metabolomics has been evaluated for the first time in discriminating LN patients from non-nephritis lupus patients (SLE) and further to get new insights into the underlying disease processes for better clinical management. Metabolic profiling of sera obtained from 22 SLE patients, 40 LN patients and 30 healthy controls (HC) were performed using high resolution 1D 1H-CPMG and diffusion edited NMR spectra to identify the potential molecular biomarkers. Using multivariate analysis, we could distinguish SLE and LN patients from HC and LN from SLE patients. Compared to SLE patients, the LN patients had increased serum levels of lipid metabolites (including LDL/VLDL lipoproteins), creatinine and decreased levels of acetate. Our results revealed that metabolic markers especially lipids and acetate derived from NMR spectroscopy has high sensitivity and specificity to distinguish LN among SLE patients and has the potential to be a useful adjunctive tool in diagnosis and clinical management of LN.

NMR-Based Serum Metabolomics Discriminates Takayasu Arteritis from Healthy Individuals: A Proof-of-Principle Study.

Takayasu arteritis (TA) is a debilitating, systemic disease that involves the aorta and large arteries in a chronic inflammatory process that leads to vessel stenosis. Initially, the disease remains clinically silent (or remains undetected) until the patients present with vascular occlusion. Therefore, new methods for appropriate and timely diagnosis of TA cases are needed to start proper therapy on time and also to monitor the patient's response to the given treatment. In this context, NMR-based serum metabolomic profiling has been explored in this proof-of-principle study for the first time to determine characteristic metabolites that could be potentially helpful for diagnosis and prognosis of TA. Serum metabolic profiling of TA patients (n = 29) and healthy controls (n = 30) was performed using 1D (1)H NMR spectroscopy, and possible biomarker metabolites were identified. Using projection to least-squares discriminant analysis, we could distinguish TA patients from healthy controls. Compared to healthy controls, TA patients had (a) increased serum levels of choline metabolites, LDL cholesterol, N-acetyl glycoproteins (NAGs), and glucose and (b) decreased serum levels of lactate, lipids, HDL cholesterol, and glucogenic amino acids. The results of this study are preliminary and need to be confirmed in a prospective study.

Neuro-cognitive aspects of "OM" sound/syllable perception: A functional neuroimaging study.

The sound "OM" is believed to bring mental peace and calm. The cortical activation associated with listening to sound "OM" in contrast to similar non-meaningful sound (TOM) and listening to a meaningful Hindi word (AAM) has been investigated using functional magnetic resonance imaging (MRI). The behaviour interleaved gradient technique was employed in order to avoid interference of scanner noise. The results reveal that listening to "OM" sound in contrast to the meaningful Hindi word condition activates areas of bilateral cerebellum, left middle frontal gyrus (dorsolateral middle frontal/BA 9), right precuneus (BA 5) and right supramarginal gyrus (SMG). Listening to "OM" sound in contrast to "non-meaningful" sound condition leads to cortical activation in bilateral middle frontal (BA9), right middle temporal (BA37), right angular gyrus (BA 40), right SMG and right superior middle frontal gyrus (BA 8). The conjunction analysis reveals that the common neural regions activated in listening to "OM" sound during both conditions are middle frontal (left dorsolateral middle frontal cortex) and right SMG. The results correspond to the fact that listening to "OM" sound recruits neural systems implicated in emotional empathy.

Effect of "SOHAM" meditation on the human brain: an fMRI study.

The effect of "SOHAM" meditation has been investigated using functional magnetic resonance imaging (fMRI) in long-term meditators while they were meditating and not meditating. The results have revealed activation in left middle prefrontal cortex (MPFC) (Brodmann's area, BA 46), left inferior frontal gyrus (LIFG) (BA 44), left supplementary motor area (SMA) (BA 6) and left precuneus (BA 5) during the meditation period compared to the control period (no-meditation period). The results have been interpreted in terms of regulation of the emotional state, attention and working memory of the meditators.

Early prognostic markers for fatal fulminant hepatic failure cases with viral hepatitis: proton nuclear magnetic resonance spectroscopic studies of serum.

BACKGROUND: Fulminant hepatic failure is associated with liver metabolic derangements which could have fatal consequences. The aim of the present study is to identify serum markers for early prediction of the outcome. METHODS: Proton nuclear magnetic resonance spectroscopic studies of serum of fulminant hepatic failure patients due to viral hepatitis with grade II/III of encephalopathy (twenty-four: ten prospective and fourteen retrospective) and twenty-five controls were undertaken. Of the twenty-four patients, fifteen survived with medical management alone while nine had fatal outcome. RESULTS: The results demonstrated significantly elevated indices of amino acids (alanine, lysine, glutamine, histidine, tyrosine, phenylalanine and 1,2-propanediol) in fatal cases compared to survivors and controls. Principal component analysis showed clear separation of fatal and surviving cases. Liver function parameters were significantly deranged in patients but they failed to provide early significant differences between surviving and fatal cases. Compared to model for end-stage liver disease scores, principal component analysis appear to be better as an early prognostic indicator. Biochemical mapping of pathways suggested interruptions in amino acid metabolism and urea cycle. CONCLUSIONS: Proton nuclear magnetic resonance studies of serum have the potential of rapidly identifying patients with irreversible fulminant hepatic failure requiring liver transplantation as life saving option.

Broad identification of bacterial type in urinary tract infection using (1)h NMR spectroscopy.

To address the shortcomings of urine culture for the rapid identification of urinary tract infection (UTI), we applied (1)H-nuclear magnetic resonance (NMR) spectroscopy as a surrogate method for fast screening of microorganisms. Study includes 682 urine samples from suspected UTI patients, 50 healthy volunteers, and commercially available standard strains of gram negative bacilli (GNB) (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterobacter, Acinetobacter, Proteus mirabilis, Citrobacter frundii) and gram positive cocci (GPC) (Enterococcus faecalis, Streptococcus group B, Staphylococcus saprophyticus). Acetate, lactate, ethanol, succinate, creatinine, trimethylamine (TMA), citrate, trimethylamin-N-oxide, glycine, urea, and hippurate were measured by (1)H NMR spectroscopy. All urine specimens were evaluated with culture method. Multivariate discriminant function analysis (DFA) reveals that acetate, lactate, succinate, and formate were able to differentiate, with high accuracy (99.5%), healthy controls from UTI patients. This statistical analysis was also able to classify GNB to GPC infected urine samples with high accuracy (96%). This technique appears to be a promising, rapid, and noninvasive approach to probing GNB and GPC infected urine specimens with its distinguishing metabolic profile. The determination of infection will be very important for rapidly and efficiently measuring the efficacy of a tailored treatment, leading to prompt and appropriate care of UTI patients.

Inhibition of adherence of multi-drug resistant E. coli by proanthocyanidin.

Proanthocyanidin is commonly used for inhibiting urinary tract infection (UTI) of sensitive strains of Escherichia coli. The aim of this study was to investigate the effect of proanthocyanidin on adherence of uropathogenic multi-drug resistant E. coli to uroepithelial cells, which has not yet been investigated so far. Extracts of the purified proanthocyanidin were prepared from dried cranberry juice. Purity and structural assignment of proanthocyanidin was assessed using high performance liquid chromatography and (13)C nuclear magnetic resonance spectroscopy, respectively. Subsequently, its affect on multi-drug resistant bacteria as well as quantification of anti-adherence bioactivity on human vaginal and bladder epithelial cells was appraised. Inhibition of adherence to an extent of about 70% with multi-drug resistant E. coli strains was observed on uroepithelial cell. The anti-adherence bioactivity of the proanthocyanidin was detected at concentrations of 10-50 µg/ml with significant bacteriuria. Probable proanthocyanidin through A-type linkages either combines to P-fimbriae of bacterial cells or modifies the structural entity of P-fimbriae and inhibits bacterial adherence to uroepithelial cells. The proanthocyanidin exhibited anti-adherence property with multi-drug resistant strains of uropathogenic P-fimbriated E. coli with in vitro study. Hence proanthocyanidin may be considered as an inhibitory agent for multi-drug resistant strains of E. coli adherence to uroepithelial cells.

Restoration of hepatocytes function following decompression therapy in extrahepatic biliary obstructed patients: metabolite profiling of bile by NMR.

Prolonged biliary obstruction and infection cause retention of biliary constituents in liver followed by hepatocyte dysfunction. Decompression therapy is important for both management and prognostic reasons and restores hepatocyte function. Quantitative metabolite profiling of bile using NMR spectroscopy at the time of obstruction and serially following decompression therapy using percutaneous transhepatic biliary drainage (PTBD) from nineteen patients with extrahepatic malignant biliary obstruction are presented. Based on detailed history, clinical condition, total leucocyte counts (TLC) and microbiological cultures of bile, patients were classified in two groups depending upon absence or presence of cholangitis. Statistical analysis was performed for comparison within each group using Wilcoxan sign square rank test. TLC and liver function tests indicated a trend towards recovery following decompression by one week. While on day 0 biliary constituents were undetectable in both the groups of patients, they increased significantly following one week of drainage with better recovery in patients with cholangitis compared to without. Free amino acids' signals were detected in all specimens starting from day 1 after decompression. This indicates disruption of blood-bile barrier during cholestasis and slow restoration of tight junction of hepatocytes following decompression leading to the appearance of biliary constituents in bile. Decompression therapy tends to restore biliary constituents with a prompt recovery in patients with cholangitis further supports such therapy for clinical management and outcome. To our knowledge this is the first report on the detection of amino acids in bile taken from common bile duct though they have been reported in hepatic bile.

1H-nuclear magnetic resonance spectroscopy for identifying and quantifying common uropathogens: a metabolic approach to the urinary tract infection.

OBJECTIVE: To address the shortcomings of urine culture for the diagnosis of urinary tract infection (UTI), we used 1H-nuclear magnetic resonance (NMR) spectroscopy for identifying and quantifying Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia and Proteus mirabilis. PATIENTS, SUBJECTS AND METHODS: Urine samples from patients with suspected UTI (617), healthy volunteers (50) and commercially available standard strains of E. coli, K. pneumonia, P. aeruginosa, Enterobacter, Acinobacter, Pr. mirabilis, Citrobacter frundii, Streptococcus saprophyticus and Enterococcus faecalis were assessed between 2003 and 2006. 1H-NMR spectra were recorded on a 400 MHz spectrophotometer; to quantify the bacteria we estimated the areas under the spectral peaks of the specific metabolic product compared with the known concentration of trimethyl silyl propionic acid. All urine specimens were cultured in addition to an assessment by NMR spectroscopy. RESULTS: Preliminary urinary spectroscopy of the unprocessed samples showed peaks of nonspecific metabolites such as succinate, acetate, lactate and ethanol, indicating infected samples. Based on the results from processed samples, 93% (240/256) of E. coli, 92% (101/110) of K. pneumoniae, 93% (56/60) of P. aeruginosa and eight of 10 Pr. mirabilis could be diagnosed with NMR (numerator) and urine culture (denominator). The remaining samples were sterile and/or had a bacterial population of <10(3) colony-forming units (CFU)/mL. The NMR method diagnosed bacterial densities of >10(3) CFU. CONCLUSIONS: The identification of the common uropathogens E. coli, K. pneumoniae, P. aeruginosa and Pr. mirabilis by NMR spectroscopy has a shorter reporting time and can be used to differentiate between infected, contaminated and sterile specimens.