Clinical metabolomics by NMR revealed serum metabolic signatures for differentiating sarcoidosis from tuberculosis.

BACKGROUND: Pulmonary sarcoidosis (SAR) and tuberculosis (TB) are two granulomatous lung-diseases and often pose a diagnostic challenge to a treating physicians. OBJECTIVE: The present study aims to explore the diagnostic potential of NMR based serum metabolomics approach to differentiate SAR from TB. MATERIALS AND METHOD: The blood samples were obtained from three study groups: SAR (N = 35), TB (N = 28) and healthy normal subjects (NC, N = 56) and their serum metabolic profiles were measured using 1D 1H CPMG (Carr-Purcell-Meiboom-Gill) NMR spectra recorded at 800 MHz NMR spectrometer. The quantitative metabolic profiles were compared employing a combination of univariate and multivariate statistical analysis methods and evaluated for their diagnostic potential using receiver operating characteristic (ROC) curve analysis. RESULTS: Compared to SAR, the sera of TB patients were characterized by (a) elevated levels of lactate, acetate, 3-hydroxybutyrate (3HB), glutamate and succinate (b) decreased levels of glucose, citrate, pyruvate, glutamine, and several lipid and membrane metabolites (such as very-low/low density lipoproteins (VLDL/LDL), polyunsaturated fatty acids, etc.). CONCLUSION: The metabolic disturbances not only found to be well in concordance with various previous reports, these further demonstrated very high sensitivity and specificity to distinguish SAR from TB patients suggesting serum metabolomics analysis can serve as surrogate method in the diagnosis and clinical management of SAR.

How Does Literacy Affect Speech Processing? Not by Enhancing Cortical Responses to Speech, But by Promoting Connectivity of Acoustic-Phonetic and Graphomotor Cortices.

Previous research suggests that literacy, specifically learning alphabetic letter-to-phoneme mappings, modifies online speech processing and enhances brain responses, as indexed by the BOLD, to speech in auditory areas associated with phonological processing (Dehaene et al., 2010). However, alphabets are not the only orthographic systems in use in the world, and hundreds of millions of individuals speak languages that are not written using alphabets. In order to make claims that literacy per se has broad and general consequences for brain responses to speech, one must seek confirmatory evidence from nonalphabetic literacy. To this end, we conducted a longitudinal fMRI study in India probing the effect of literacy in Devanagari, an abubgida, on functional connectivity and cerebral responses to speech in 91 variously literate Hindi-speaking male and female human participants. Twenty-two completely illiterate participants underwent 6 months of reading and writing training. Devanagari literacy increases functional connectivity between acoustic-phonetic and graphomotor brain areas, but we find no evidence that literacy changes brain responses to speech, either in cross-sectional or longitudinal analyses. These findings shows that a dramatic reconfiguration of the neurofunctional substrates of online speech processing may not be a universal result of learning to read, and suggest that the influence of writing on speech processing should also be investigated.SIGNIFICANCE STATEMENT It is widely claimed that a consequence of being able to read is enhanced auditory processing of speech, reflected by increased cortical responses in areas associated with phonological processing. Here we find no relationship between literacy and the magnitude of brain response to speech stimuli in individuals who speak Hindi, which is written using a nonalphabetic script, Devanagari, an abugida. We propose that the exact nature of the script under examination must be considered before making sweeping claims about the consequences of literacy for the brain. Further, we find evidence that literacy enhances functional connectivity between auditory processing areas and graphomotor areas, suggesting a mechanism whereby learning to write might influence speech perception.

Structure-Correlated Magnetic Resonance Transverse Relaxivity Enhancement in Superparamagnetic Ensembles with Complex Anisotropy Landscape.

The aim of the work is to explore structure-relaxivity relationship by observing transverse relaxivity enhancement in magnetic resonance imaging (MRI) of differently organized superparamagnetic complex ensembles of zinc ferrite isotropic/anisotropic nanosystems. We observe that superparamagnetic systems show a correlation of MRI-transverse relaxivity, r2/r1, with spatial arrangement of nanoparticles, as well as magnetic easy axes and thermal-energy-dependent anisotropy energy landscape. The presence of highly random/partially aligned easy axes with enhanced anisotropy constant leads to modulation in transverse relaxation. As a result, we achieve highest contrast efficiency in compact ensemble of isotropic nanoparticles and hollow core ensemble. Indeed, core-shell ensemble with combined effect of aligned and randomly oriented easy magnetic axes shows a reduction in MRI contrast efficiency. However, we address a hypothesis for transverse contrast efficiency where we depict the correlation among MRI-transverse contrast efficiency with structural complexity of ensembles, differently arranged primary nanoparticles/magnetic easy axes, anisotropy constant, and collective magnetic behavior. In consequence, we simplify the limitation of quantum mechanical outer-sphere diffusion model of magnetic resonance relaxivity by neglecting the contribution of magnetization and introducing an anisotropy constant contribution with complex structure landscape of easy axes.

Assessment of hyaluronic acid-modified imatinib mesylate cubosomes through CD44 targeted drug delivery in NDEA-induced hepatic carcinoma.

This study aimed at the development of hyaluronic acid-functionalised imatinib mesylate cubosomes (HA-IM-CBs) that might be useful in CD44 targeting against hepatic cancer. The HA-IM-CBs had a 130.7 ±â€¯2.92 nm particle size, -31.40 ±â€¯2.76 mV zeta potential, and 76.14 ±â€¯2.69% release. The architecture of HA-IM-CBs was confirmed using HR-TEM and AFM. When compared to plain IM and IM-CBs, in vitro experiments revealed that HA-IM-CBs outperformed by significantly reducing cell viability. DAPI staining and ROS corroborated the apoptotic effects. Biodistribution and Pharmacokinetics studies showedthat HA-IM-CBs exhibit a higher drug concentration in tumour tissue and better pharmacokinetic activity. This is the first study to show that HA-IM-CBs had CD44 targeting activity against HCC. CD44 regulates apoptosis via Bcl-2 family proteins and caspases, which interact with HA. Higher levels of e-NOS, BAD, BAX, and Cyt C and lower expressions of Bcl-xl, i-NOS, and Bcl-2 demonstrated the anti-HCC potential of HA-IM-CBs in qrt-PCR investigations. The remarkable therapeutic potential of HA-IM-CBs began with substantial stimulation of CD44 regulated caspase-mediated mitochondrial apoptotic pathway, accountable for their anti-HCC activity. The perturbed metabolites are restored to acceptable levels as indicated by metabolomic studies (1H NMR). Interestingly, the antineoplastic effect of HA-IM-CBs was proven to be potentially valuable against HCC.

NMR-Based Metabolomics Revealed the Underlying Inflammatory Pathology in Reactive Arthritis Synovial Joints.

Reactive arthritis (ReA) is an aseptic synovitis condition that often develops 2-4 weeks after a distant (extra-articular) infection with Chlamydia, Salmonella, Shigella, Campylobacter, and Yersinia species. The metabolic changes in the synovial fluid (SF) may serve as indicative markers to both improve the diagnostic accuracy and understand the underlying inflammatory pathology of ReA. With this aim, the metabolic profiles of SF collected from ReA (n = 58) and non-ReA, i.e., rheumatoid arthritis (RA, n = 21) and osteoarthritis (OA, n = 20) patients, respectively, were measured using NMR spectroscopy and compared using orthogonal partial least-squares discriminant analysis (OPLS-DA). The discriminatory metabolic features were further evaluated for their diagnostic potential using the receiver operating characteristic (ROC) curve analysis. Compared to RA, two (alanine and carnitine), and compared to OA, six (NAG, glutamate, glycerol, isoleucine, alanine, and glucose) metabolic features were identified as diagnostic biomarkers. We further demonstrated the impact of ReA synovitis condition on the serum metabolic profiles through performing a correlation analysis. The Pearson rank coefficient (r) was estimated for 38 metabolites (profiled in both SF and serum samples obtained in pair from ReA patients) and was found significantly positive for 71% of the metabolites (r ranging from 0.17 to 0.87).

Serum Metabolic Disturbances Associated with Acute-on-chronic Liver Failure in Patients with Underlying Alcoholic Liver Diseases: An Elaborative NMR-based Metabolomics Study.

OBJECTIVES: Acute-on-chronic liver failure (ACLF), which develops in patients with underlying alcoholic liver disease (ALD), is characterized by acute deterioration of liver function and organ failures are secondary to that. The clear understanding of metabolic pathways perturbed in ALD-ACLF patients can greatly decrease the mortality and morbidity of patients through predicting outcome, guiding treatment, and monitoring response to treatment. The purpose of this study was to investigate the metabolic disturbances associated with ACLF using nuclear magnetic resonance (NMR)-based serum metabolomics approach and further to assess if the serum metabolic alterations are affected by the severity of hepatic impairment. MATERIALS AND METHODS: The serum-metabolic profiles of 40 ALD-ACLF patients were compared to those of 49 age and sex-matched normal-control (NC) subjects making composite use of both multivariate and univariate statistical tests. RESULTS: Compared to NC, the sera of ACLF patients were characterized by significantly decreased serum levels of several amino acids (except methionine and tyrosine), lipid, and membrane metabolites suggesting a kind of nutritional deficiency and disturbed metabolic homeostasis in ACLF. Twelve serum metabolic entities (including BCAA, histidine, alanine, threonine, and glutamine) were found with AUROC (i.e., area under ROC curve) value >0.9 suggesting their potential in clinical diagnosis and surveillance. CONCLUSION: Overall, the study revealed important metabolic changes underlying the pathophysiology of ACLF and those related to disease progression would add value to standard clinical scores of severity to predict outcome and may serve as surrogate endpoints for evaluating treatment response.

Biotinylated Mn3O4 nanocuboids for targeted delivery of gemcitabine hydrochloride to breast cancer and MRI applications.

Multifunctional nanocarriers have been found as potential candidate for the targeted drug delivery and imaging applications. Herein, we have developed a biocompatible and pH-responsive manganese oxide nanocuboid system, surface modified with poly (ethylene glycol) bis(amine) and functionalized with biotin (Biotin-PEG-MNCs), for an efficient and targeted delivery of an anticancer drug (gemcitabine, GEM) to the human breast cancer cells. GEM-loaded Biotin-PEG@MNCs showed high drug loading efficiency, controlled release of GEM and excellent storage stability in the physiological buffers and different temperature conditions. GEM-loaded Biotin-PEG@MNCs showed dose- and time-dependent decrease in the viability of human breast cancer cells. Further, it exhibited significantly higher cell growth inhibition than pure GEM which suggested that Biotin-PEG@MNCs has efficiently delivered the GEM into cancerous cells. The role of biotin in the uptake was proved by the competitive binding-based cellular uptake study. A significant decrease in the amount of manganese was observed in biotin pre-treated cancer cells as compared to biotin untreated cancer cells. In MRI studies, Biotin-PEG-MNCs showed both longitudinal and transverse relaxivity about 0.091 and 7.66 mM-1 s-1 at 3.0 T MRI scanner, respectively. Overall, the developed Biotin-PEG-MNCs presents a significant potential in formulation development for cancer treatment via targeted drug delivery and enhanced MRI contrast imaging properties.

NMR-based clinical metabolomics revealed distinctive serum metabolic profiles in patients with spondyloarthritis.

Spondyloarthritis (SpA) is a common rheumatic disorder of the young, marred by delay in diagnosis, and paucity of biomarkers of disease activity. The present study aimed to explore the potential of serum metabolic profiling of patients with SpA to identify biomarker for the diagnosis and assessment of disease activity. The serum metabolic profiles of 81 patients with SpA were compared with that of 86 healthy controls (HCs) using nuclear magnetic resonance (NMR)-based metabolomics approach. Seventeen patients were followed up after 3 months of standard treatment, and paired sera were analyzed for effects of therapy. Comparisons were done using the multivariate partial least squares discriminant analysis (PLS-DA), and the discriminatory metabolic entities were identified based on variable importance in projection (VIP) statistics and further evaluated for statistical significance (p value < 0.05). We found that the serum metabolic profiles differed significantly in SpA as compared with HCs. Compared with HC, the SpA patients were characterized by increased serum levels of amino acids, acetate, choline, N-acetyl glycoproteins, Nα-acetyl lysine, creatine/creatinine, and so forth and decreased levels of low-/very low-density lipoproteins and polyunsaturated lipids. PLS-DA analysis also revealed metabolic differences between axial and peripheral SpA patients. Further metabolite profiles were found to differ with disease activity and treatment in responding patients. The results presented in this study demonstrate the potential of serum metabolic profiling of axial SpA as a useful tool for diagnosis, prediction of peripheral disease, assessment of disease activity, and treatment response.

Fabrication of Imatinib Mesylate-Loaded Lactoferrin-Modified PEGylated Liquid Crystalline Nanoparticles for Mitochondrial-Dependent Apoptosis in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a major cause of concern as it has substantial morbidity associated with it. Previous reports have ascertained the antiproliferative activity of imatinib mesylate (IMS) against diverse types of carcinomas, but limited bioavailability has also been reported. The present study envisaged optimized IMS-loaded lactoferrin (LF)-modified PEGylated liquid crystalline nanoparticles (IMS-LF-LCNPs) for effective therapy of IMS to HCC via asialoglycoprotein receptor (ASGPR) targeting. Results displayed that IMS-LF-LCNPs presented an optimum particle size of 120.40 ± 2.75 nm, a zeta potential of +12.5 ± 0.23 mV, and 73.94 ± 2.69% release. High-resolution transmission electron microscopy and atomic force microscopy were used to confirm the surface architecture of IMS-LF-LCNPs. The results of cytotoxicity and 4,6-diamidino-2-phenylindole revealed that IMS-LF-LCNPs had the highest growth inhibition and significant apoptotic effects. Pharmacokinetics and biodistribution studies showed that IMS-LF-LCNPs have superior pharmacokinetic performance and targeted delivery compared to IMS-LCNPs and plain IMS, which was attributed to the targeting action of LF that targets the ASGPR in hepatic cells. Next, our in vivo experiment established that the HCC environment existed due to suppression of BAX, cyt c, BAD, e-NOS, and caspase (3 and 9) genes, which thus owed upstream expression of Bcl-xl, iNOS, and Bcl-2 genes. The excellent therapeutic potential of IMS-LF-LCNPs began the significant stimulation of caspase-mediated apoptotic signals accountable for its anti-HCC prospect. 1H nuclear magnetic resonance (serum) metabolomics revealed that IMS-LF-LCNPs are capable of regulating the disturbed levels of metabolites linked to HCC triggered through N-nitrosodiethylamine. Therefore, IMS-LF-LCNPs are a potentially effective formulation against HCC.

Targeted NMR-based serum metabolic profiling of serine, glycine and methionine in acute-on-chronic liver failure patients: Possible insights into mitochondrial dysfunction.

Background: A recent study based on blood metabolomics analysis revealed inflammation-associated mitochondrial dysfunction as a potential mechanism underlying acute-on-chronic liver failure (ACLF) in cirrhotic patients. Serine, glycine, and methionine serve to maintain a healthy immune system and adequately sustain mitochondrial functionality in hepatocytes for regulating redox homeostasis through the production of antioxidant glutathione (GSH). Based on this, we hypothesized that the circulatory levels of serine, glycine and methionine will be altered in ACLF patients due to acute worsening of hepatic function and may provide novel insights into the mitochondrial dysfunction as well. Methods: The circulatory concentrations of serine, glycine, and methionine were estimated in the sera of 40 ACLF patients and 49 normal controls (NC) subject using 1D 1H-CPMG NMR spectra recorded at 800 MHz NMR spectrometer. The resulting metabolite concentrations were compared using unpaired Student t-test and p-value < 0.05 was considered as the criterion of statistical significance. The diagnostic potential and statistical correlations were established using receiver-operating-characteristic (ROC) curve analysis and Pearson-r method, respectively. Results: Circulating levels of serine and glycine were significantly decreased in ACLF patients (Ser = 23.06 ± 1.67 µM and Gly = 83.11±7.52 µM) compared to NC subjects (Ser = 55.61 ± 2.28 µM and Gly = 156.9±7.16 µM) with p-value < 0.0001, whereas those of methionine were significantly increased in ACLF (22.60 ± 2.49 µM) compared to NC subjects (=14.63 ± 0.85 µM) with p-value < 0.0015. Further, the ROC analysis yielded satisfactory sensitivity and specificity for serine, glycine, and methionine-to-glycine ratio (MGR) with area under ROC (AUROC) curve values equal to: 0.95 [95%CI = 0.91-0.99] for Ser; 0.87 [95%CI = 0.79-0.95] for Gly; and 0.90 [95%CI = 0.83-0.97] for MGR. Conclusion: Compared to NC subjects, the sera of ACLF patients were characterized by hypermethioninemia and aberrantly decreased levels of serine and glycine suggesting mitochondrial dysfunction as the possible mechanism for disturbed redox homeostasis and therefore depressed immune system in ACLF.

NMR-based serum and muscle metabolomics for diagnosis and activity assessment in idiopathic inflammatory myopathies.

Objectives: Differentiating smoldering disease activity from weakness due to fatty replacement of atrophied muscle can often be a challenge in the idiopathic inflammatory myositis (IIM). We aimed to identify the metabolic disturbances associated with IIM and if these changes can aid in the assessment of disease activity. Methods: Metabolic profiles of sera (N = 99) and muscle (N = 21) from patients with IIM (ACR-EULAR criteria) were compared with healthy control (HC) samples (N = 75 for serum and N = 12 for muscle tissues) employing 800 MHz NMR (Nuclear Magnetic Resonance) spectroscopy. Metabolic disparity between IIM and HC was established based on Partial Least Squares Discriminant Analysis (PLS-DA) and the discriminatory metabolites were identified based on variable importance in projection (VIP) statistics (P-value < .05, corrected for false discovery rate (FDR)). Results: Serum metabolomics profiles were distinctive in IIM as compared to HC, with a visible shift to anaerobic metabolism (increased lactate, low glucose), oxidative defect (high Phenylalanine/tyrosine), decreased muscle mass (low serum creatinine), increased muscle catabolism (increased branched-chain amino acids), and dyslipidemia (higher lipids, higher very low-density lipoprotein [VLDL]/low-density lipoprotein [LDL] ratio, lower polyunsaturated fatty acid [PUFA]). The sera of active IIM patients were characterized by anaerobic metabolism (low glucose), loss of muscle mass (low creatinine, amino acids), and oxidative defect (high Phenylalanine/tyrosine). Three metabolites (isopropanol, succinate, and glycine) were distinctive in muscle tissue metabolomics. NMR-based serum metabolic disparity was lacking between different clinical subsets of IIM. Conclusion: Serum and muscle tissue metabolomics have the potential to distinguish (a) IIM from HC and (b) active IIM from inactive IIM irrespective of disease subtype.

Circulatory histidine levels as predictive indicators of disease activity in takayasu arteritis.

Background and objective: Quantitative assessment of disease activity is important for effective management of patients with autoimmune inflammatory diseases (AIDs) including Takayasu arteritis (TA).  Histidine supplementation alleviates inflammation and has strong anti-oxidative effects as well. The present study aims to evaluate the diagnostic potential of circulatory histidine for predicting disease activity in TA. Methods: The serum metabolic profiles on 98 TA-patients and 77 normal controls (NC) samples were measured at high-resolution 800 MHz NMR spectrometer employing standard 1D-1H-CPMG NMR experiments. The NMR spectral data were processed and concentrations of histidine and other circulatory metabolites were estimated with respect to formate (as an internal reference) and compared using ANOVA based on Tukey's multiple comparison test and statistical significance was considered at P-value < 0.05. The correlations of histidine with plasma CRP and ESR levels were evaluated using Spearman-r method. Data were expressed as median (interquartile-range [IQR]). Results: Histidine levels were significantly decreased in active TA patients (23.90; IQR:16.10) compared to both inactive TA patients (35.50, IQR:24.30) and NC (42.80, IQR:22.10), whereas there was no significant difference between inactive TA and NC. For TA patients, the histidine levels correlated negatively with clinical markers of inflammation, that is, ESR (r = -0.19, P < .078) and with the CRP (r = -0.26, P < .013). Further, the receiver-operating-characteristic (ROC) curve analysis was performed to test the diagnostic potential of histidine for differentiating active from inactive disease. The area under the ROC curve (AUROC) value equal to 0.65 [95% CI = 0.54-0.76] revealed its moderate discriminatory ability. Compared to other circulatory metabolites, the discriminatory performance of histidine was also found to be in the moderate range (highest AUROC-value of 0.76 was found for glutamine-to-glucose ratio (QGR). Conclusion: The study demonstrated the altered circulatory histidine levels in TA patients that may serve as a surrogate marker for improving the diagnostic screening of active and inactive TA patients.

Nuclear magnetic resonance-based targeted profiling of urinary acetate and citrate following cyclophosphamide therapy in patients with lupus nephritis.

OBJECTIVE: Metabolomics, the study of global alterations in small metabolites, is a useful tool to look for novel biomarkers. Recently, we reported a reprogramming of the serum metabolomic profile by nuclear magnetic resonance (NMR) spectroscopy following treatment in lupus nephritis (LN). This study aimed to compare the urine excretory levels of citrate and acetate in patients with biopsy-proven LN before and six months after cyclophosphamide induction therapy and to evaluate their correlation with the Systemic Lupus Erythematosus Disease Activity Index 2K (SLEDAI 2K) and renal SLEDAI. METHODS: Urine obtained from LN patients (N = 18, 16 female) at diagnosis and six months following induction therapy with cyclophosphamide and healthy controls (HC; N = 18, median age = 35 years, all female) were stored at -80°C. Metabolomic profiling was done using high resolution 800 MHz 1D 1H NMR spectroscopy. The urinary ratio of metabolites was calculated as (metabolite×1000)/creatinine. Disease activity was measured using the SLEDAI. Metabolomic profiles were compared between groups and correlated with clinical parameters. RESULTS: Compared to HC, LN patients had significantly lower median urinary citrate/creatinine levels (LN = 18.26, range 12.80-27.62; HC = 107.7, range 65.39-138.4; p < 0.0001) which significantly increased after six months of cyclophosphamide treatment (51.05, range 11.51-170.2; p = 0.03). LN patients also differed from HC by having a higher mean urinary acetate/creatinine ratio (LN = 17.44, range 11.6-32.7; HC = 9.61, range 7.97-13.71; p = 0.054) with a non-significant fall in values after six months of treatment. The Area under curve for differentiating LN from HC for urinary citrate was 0.9136, and urinary acetate was 0.6883. The urinary acetate levels correlated with SLEDAI (r = 0.337, p = 0.048). Urinary citrate levels correlated positively with C3 (r = 0.362, p = 0.03) and negatively with urine protein/creatinine (r = -0.346, p = 0.039). CONCLUSIONS: Urinary citrate, which reflects dampened aerobic glycolysis and oxidative phosphorylation, improved significantly and is a potential non-invasive biomarker for diagnosis and monitoring treatment response in LN.

Circulatory Glutamine/Glucose ratio for evaluating disease activity in Takayasu arteritis: A NMR based serum metabolomics study.

Quantitative assessment of disease activity is important for effective care of patients with Takayasu arteritis (TA). Activated glutaminolysis and reduced glycolytic flux is the hallmark of active inflammation. Based on this, we hypothesize that the circulatory Glutamine/Glucose ratio (QGR) can serve as an indicant of active inflammation in TA. To probe this hypothesis, the serum samples were collected from 45 active and 53 inactive TA patients fulfilling American College of Rheumatology (ACR) criteria and assessed for disease activity according to Indian Takayasu Clinical Activity Score (ITAS) using acute phase reactant-erythrocyte sedimentation rate [ITAS-A (ESR)]. The quantitative profiles of circulatory metabolites implicated in glutaminolysis (Glutamine and Glutamate) and those which estimate glycolytic flux (i.e. glucose and lactate) were measured using high field (800 MHz) NMR spectroscopy. The recorded spectra were analyzed using CHENOMX NMR Suite and the estimated concentration profiles were compared and evaluated for their diagnostic potential using Metaboanalyst. Compared to inactive-TA patients, the sera of active-TA patients were characterized by significantly decreased serum levels of glutamine and lactate suggesting that these patients exhibit activated glutaminolysis and reduced glycolytic activity. This is further supported by significantly decreased QGR and lactate to glucose ratio (LGR) levels in active compared to inactive TA patients. The receiver operating characteristic (ROC) curve analysis revealed satisfactory accuracy, sensitivity and specificity for QGR [with area under ROC curve (AUROC) = 0.76 and 95% confidence interval (CI) = 0.66-0.84) compared to that for LGR (with AUROC = 0.67 and CI = 0.561-0.77). Therefore, we believe that the circulatory QGR has the potential to serve as surrogate marker for the assessment of disease activity in TA patients. However, the use of this ratio in clinical settings will require future studies on large patient cohorts and procedural optimization as well to improve accuracy.

Metabolomics analysis revealed significantly higher synovial Phe/Tyr ratio in reactive arthritis and undifferentiated spondyloarthropathy.

OBJECTIVE: To compare the synovial phenylalanine/tyrosine (Phe/Tyr) ratio between ReA/uSpA and RA and OA by NMR spectroscopy. METHODS: Paired SF and serum of 30 patients with ReA/uSpA were collected and analysed using a 1D 1H Carr Purcell Meiboom Gill NMR spectra recorded on 800 MHz NMR spectrometer equipped with a TCI Cryoprobe (at 300 K). Phe and Tyr were quantified. SF from 25 patients with RA fulfilling ACR classification criteria and 21 patients with OA were taken as inflammatory and non-inflammatory controls. RESULTS: The synovial Phe/Tyr ratio was significantly higher in ReA/uSpA compared with RA and OA. Synovial Phe/Tyr ratios were comparable in RA and OA patients. Compared with serum, the Phe/Tyr was significantly higher in the SF in ReA/uSpA. The Phe/Tyr ratio was also found to be positively correlated between serum and SF samples, with a regression coefficient (r2) of 0.287. CONCLUSIONS: This NMR-based metabolomics study demonstrates that the synovial Phe/Tyr ratio is specifically elevated in ReA/uSpA.

Modulating the Delivery of 5-Fluorouracil to Human Colon Cancer Cells Using Multifunctional Arginine-Coated Manganese Oxide Nanocuboids with MRI Properties.

5-Fluorouracil (5-FU) is one of the most prescribed drugs and the major component of chemotherapy for the treatment of colorectal cancer. In this study, we have designed arginine-functionalized manganese oxide nanocuboids (Arg@MNCs) for the effective delivery of 5-FU to colon cancer cells. Arginine was used as multifunctional agent to provide stability to MNCs, achieve high drug loading, control the release of loaded drug, and improve delivery to cancer cells. The synthesized Arg@MNCs were characterized by DLS, TEM, XRD, FTIR, XPS, TGA, and VSM analysis. The structural and morphological analysis by TEM showed cuboid-shaped MNCs with average particle size ∼15 nm. Biodegradation studies indicated that the Arg@MNCs were degraded at endolyosomal pH in 24 h while remaining stable at physiological pH. Hemolytic toxicity studies revealed the safety and nontoxic nature of the prepared MNCs. 5-FU-loaded Arg@MNCs showed significant control over the release of 5-FU, decrease in the hemolytic toxicity of loaded 5-FU but higher in vitro anticancer activity against HCT 116 and SW480 human colon cancer cells. Importantly, both the bare MNCs and Arg@MNCs showed excellent T1 and T2MR relaxivity under 3.0 T MRI scanner. Thus, the nanostructures developed in this study, i.e., 5-FU-Arg@MNCs could overcome the issues of both MNCs (stability) and 5-FU (low drug loading and nonspecificity) and may be used as a multifunctional theranostic nanocarrier for colon cancer treatment.

Physicochemical and Antibacterial Properties of PEGylated Zinc Oxide Nanoparticles Dispersed in Peritoneal Dialysis Fluid.

Owing to the peculiar broad-spectrum antimicrobial activities of zinc oxide nanoparticles (ZnO NPs), we envisaged their use to treat bacterial/mycobacterial/fungal infections during peritoneal dialysis (PD) of end-stage renal failure patients. However, a recent study from our lab showed that ZnO-NPs cannot be employed for the same in their naked form owing to their rapid agglomeration. Also, the naked ZnO-NPs showed strong interaction with organic acids present in the PD fluid (i.e., lactate and citrate present abundantly in almost all biological fluids) resulting in the formation of bioconjugates. Here, we propose that the surface coating of ZnO NPs may inhibit the binding interactions of NPs with the constituents of PD fluid. Therefore, in this study, we have carried out the surface coating of ZnO NPs with polyethylene glycol (PEG) of different molecular weights, followed by the investigations of physicochemical properties of PEGylated ZnO NPs dispersed in PD fluid using nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. The interaction of PEGylated ZnO NPs has also been studied separately in glucose and lactic acid which are the main constituents of PD fluid and in citric acid. Although the X-ray diffraction and TEM results infer the colloidal stability of PEGylated ZnO NPs in PD fluid, FT-IR, UV-vis, and nuclear magnetic resonance results revealed the binding interactions of PEGylated ZnO NPs with the PD constituents. PEGylated ZnO NPs also interact strongly with the lactic acid and citric acid, leading to agglomeration, as observed previously for uncoated ZnO NPs. Further, the antibacterial activities of bare and PEG-coated ZnO NPs dispersion in PD fluid have been studied. A reduction in the bacterial inhibition effect against Staphylococcus aureus and Escherichia coli was observed for both the bare and PEG-coated ZnO NPs dispersed in PD fluid, indicating that the complex nature of PD fluid counteract on the efficiency of these nanobiotics.

Learning to read recycles visual cortical networks without destruction.

Learning to read is associated with the appearance of an orthographically sensitive brain region known as the visual word form area. It has been claimed that development of this area proceeds by impinging upon territory otherwise available for the processing of culturally relevant stimuli such as faces and houses. In a large-scale functional magnetic resonance imaging study of a group of individuals of varying degrees of literacy (from completely illiterate to highly literate), we examined cortical responses to orthographic and nonorthographic visual stimuli. We found that literacy enhances responses to other visual input in early visual areas and enhances representational similarity between text and faces, without reducing the extent of response to nonorthographic input. Thus, acquisition of literacy in childhood recycles existing object representation mechanisms but without destructive competition.

Neurocognitive mechanisms of affective conflict adaptation: An event related fMRI study.

Control of conflict can be seen in reduced effects of conflict following incompatible trials known as conflict adaptation. Such control mechanisms have been shown to depend on emotional content present in stimuli, which could be a motivational force for control adjustments. We explored the neural mechanisms of the interaction between proactive control in terms of conflict adaptation effect and emotions through an event related fMRI study involving an emotional Stroop effect (facial expression-emotional word paradigm) involving happy and angry expressions. Conflict adaptation was measured in terms of the reduction in Stroop effect as a function of previous trial congruence and previous trial emotion. Participants responded to the facial expression while ignoring the distractor word written over the face. Behavioral results showed larger Stroop effect for angry faces compared to happy faces. Conflict adaptation effect was greater for angry faces and was also influenced by previous trial emotion. Both priming and adaptation effects were observed. Stroop effect was correlated with activations in dorsal anterior cingulate. Emotion effect was correlated with activations in amygdala, fusiform face area (FFA), and insula along with the expected hemispheric asymmetry for positive and negative emotions in left vs right FFA, respectively. Conflict adaptation effect was correlated with activations in amygdala. In addition, activations in striatum supported the three-way interaction between emotion, previous and current trial congruence. Activation in dorsal anterior cingulate was correlated only with the overall Stroop effect in the current trial. Activations in amygdala and striatum were also found with facial expressions. The results indicate that emotion specific processing areas themselves such as amygdala and striatum may self-regulate and contribute toward enhanced proactive control mechanisms for task-relevant emotional stimuli. These findings further confirm the strong relationship between cognition and affect in the context of conflict monitoring and adjustments in cognitive control.

Concentrative (Sahaj Samadhi) meditation training and visual awareness: An fMRI study on color afterimages.

All of us consciously experience the world around us through our sensory modalities. Empirical studies on the relationship between attention and awareness have shown that attention does influence perceptual experience or appearance in addition to better performance in perceptual tasks. The practice of meditation also changes perceptual experience in addition to better perceptual performance. For example, a study with Sahaj Samadhi meditators utilizing negative color afterimages had shown that concentrative meditation influences visual experience. However the brain regions that are modified by meditation practice leading to such changes in visual experience or awareness are still not known. Here using negative color afterimages in a functional MRI study, we investigated the brain mechanisms underlying the changes in visual awareness as a function of attentional enhancement achieved through long-term concentrative meditation practice. We found increased activity in right lateralized inferior occipital and inferior frontal cortex, which suggests the importance of attentional control in modulating visual awareness. The results of this study indicate that the link between attention and conscious experience is possibly changed by meditation practices.