Controlling formation of metal ion adducts and enhancing sensitivity in Liquid Chromatography Mass Spectrometry

Formation of metal ion adducts in mass spectrometry, particularly in electrospray ionization liquid chromatography mass spectrometry (ESI-LC-MS), is a nightmare scenario for an analyst dealing with quantitative analysis. We have studied in detail the metal adduct formation and concluded  that the use of fluorinated alkanoic acids along with formic acid and volatile ammonium salts was extremely useful in suppressing metal adduct formation in positive ion mode of ESI-LC-MS. The extremely high electronegativity of fluorine atom and unique electrostatic nature of C—F bond coupled with stereo-electronic interactions with neighboring bonds or lone pairs enables the polyfluorinated alkanoic acids in trapping highly electropositive ions (Na+, K+) thereby letting proton do its job efficiently. Addition of formic acid, trifluoroacetic acid, heptafluorobutyric acid and ammonium acetate was found to be extremely effective in controlling metal ion adducts and producing [M+H]+ ions almost exclusively resulting in significant increase in the sensitivity. This technique has been successfully used in our laboratory for the estimation of targeted and nontargeted analysis of pesticides, marine toxins, drugs and pharmaceuticals etc. in various matrices including environmental waters using liquid chromatography-time of flight mass spectrometer operated in all ion acquisition mode and triple quadruples (QQQ) in multiple reaction monitoring (MRM) mode

Targeted and non-targeted analysis of organic compounds of moderate polarity in water using liquid chromatography-time of flight mass spectrometry in all ion mode with particular reference to analysis of pesticides

We have developed a novel yet efficient method for the multi residue analysis of organic compounds of diverse polarities in water using Liquid Chromatography-Time of Flight mass spectrometry (LC-MS-TOF) equipped with a jet stream Electrospray ionization (ESI) source. Use of three different fragmentor voltages (low, medium and high) enabled the qualitative and quantitative analysis of a diverse range of targeted organic compounds in environmental waters. No prior optimization of compounds being quantified was required, the limiting factors were ionization behaviour of compounds under conditions of ESI and good chromatography. Same data file could be subjected to repeated post-run data analysis to figure out the presence of non-targeted compounds, including designer drugs if any. The technique has been illustrated with reference to a group of pesticides having diverse chromatographic and ionization behaviours. The optimized Solid Phase Extraction (SPE)  followed by method validation yielded a robust yet simple quantitative method for a group of fourteen pesticides. We were able to achieve quantitation at 10 ng/L or lower depending upon ionization behaviour of substrates against the usual regulatory requirement of 1000 ng/L. The method was used for targeted and non-targeted detection of pesticides in Nueces estuary waters, TX, USA, and several untargeted pesticides, pharmaceuticals and personal care products were identified

A Novel Wideband Magneto-Electric Dipole Antenna with Improved Feeding Structure

A novel feeding structure in magneto-electric dipole antenna is proposed and analyzed, which is simpler and better in performance than previous designs, involving differential feeding.  Due to this improved feeding structure, the antenna has achieved an impedance bandwidth of 133.3% ( 0.5 GHz – 2.5 GHz, resulting into an ultra-wide band antenna. The maximum broadside gain 7.5dBi with unidirectional radiation pattern has also been reported for the entire the range of operation. Symmetry in E-plane and H-plane radiation patterns has been observed due to the symmetry in structure and excitation of antenna. The antenna has also been able to achieve cross polarization levels

Pattern of hepatitis B and C infection among gravid women and their newborns in a tertiary care infirmary in India

Background: The objective is to determine the prevalence of the hepatitis B and C virus among pregnant women, to assess impact of maternal hepatitis B virus (HBV) or hepatitis C virus (HCV) carrier status on pregnancy outcomes and to gauge the risk factors associated with them. Antenatal clinic attenders and women undergoing termination of pregnancy over three years.Methods: The study was conducted in Gian Sagar Medical College & Hospital, Patiala, Punjab, India. Hepatitis B antigen and Hepatitis C virus antibody testing of sera from specimens sent to the hospital laboratory for routine serological testing. The results were then linked to risk information, obstetric complications and pregnancy outcome.Results: Overall HBsAg and anti-hepatitis C antibody prevalence was 1.2% (33/2031). Increased risk of transmission was associated with sexually transmitted diseases and previous surgical procedures. High rates of preterm labor pains, CD (27.27%), and non-reassuring fetal heart rate patterns and meconium stained liquor were found in the seropositive patients.Conclusions: Maternal hepatitis B and C carrier status is an eminent risk factor for adverse pregnancy outcome.

Immediate effect of dynamic oscillatory stretching vs. neurodynamic sliding technique on stretch tolerance, popliteal angle range and hamstring flexibility in apparently healthy individuals with hamstring tightness: a pre-post clinical trail

Background: The hamstrings being postural muscles are prone to tightness which leads to muscular imbalances and inefficiency of daily living activities. Hence, the present study aims to compare two competent techniques Dynamic Oscillatory Stretching (DOS)vs. neurodynamic sliding (NDS) technique.Methods: A Total of 60 subjects were recruited (31 males, 29 females). passive 90-90 knee extension test, modified v sit to reach test and NPRS scale were used to evaluate the range, flexibility and stretch tolerance in participants pre intervention and were allotted into Group A (DOS) and Groups B. The subjects were then re-assessed immediately post intervention.Results: The results were obtained using the independent and dependent t-tests. Post intervention results were suggestive of a significant within group result with a p=0.0001 under all the parameters. Subjects in Group a showed a greater increase in the ROM while, Group B showed a better result in flexibility and stretch tolerance.Conclusions: Both the techniques are efficient and can be incorporated in sports rehabilitation to prevent on site injury thereby improving athlete’s performance

The Inside Mystery of Jejunal Gastrointestinal Stromal Tumor: A Rare Case Report and Review of the Literature

Gastrointestinal stromal tumors (GISTs) are malignant and rare form of soft tissue sarcoma of the digestive tract. The incidence of gastrointestinal stromal tumors is very low Kramer et al. 2005 Jejunal GISTs are extremely rare. Here we present a rare case of jejunal GIST with unusually large size at presentation. The patient presented with severe abdomen pain, exophytic growth, and dimorphic anemia. Surgical resection of the tumor was carried out, and operative findings revealed a 15 × 10 cm growth, arising from serosal surface of jejunum, at the antimesenteric surface. Diagnosis in this case was made by subjecting the resected specimen to immunohistochemical analysis. In view of large size of the resected tumor, and high-risk histopathological features, imatinib mesylate 400 mg once daily was given as adjuvant chemotherapy. Patient is asymptomatic without any evidence of tumor recurrence after six months of postoperative followup. Imatinib as such is recommended in metastatic, residual or recurrent cases of GISTs or which are surgically not removable; however, recent recommendations suggests the use of imatinib mesylate after radical surgery in high-risk cases, because it has shown a significant decrease in the recurrence rate, and the Food and Drug Administration (FDA) has also approved the use of imatinib as adjuvant therapy after complete resection of localized, primary GIST

Intracranial chordoma presenting as acute hemorrhage in a child: Case report and literature review

BACKGROUND: Chordomas are rare, slow-growing malignant neoplasms derived from remnants of the embryological notochord. Pediatric cases comprise only 5% of all chordomas, but more than half of the reported pediatric chordomas are intracranial. For patients of all ages, intracranial chordomas typically present with symptoms such as headaches and progressive neurological deficits occurring over several weeks to many years as they compress or invade local structures. There are only reports of these tumors presenting acutely with intracranial hemorrhage in adult patients. CASE DESCRIPTION: A 10-year-old boy presented with acute onset of headache, emesis, and diplopia. Head computed tomography and magnetic resonance imaging of brain were suspicious for a hemorrhagic mass located in the left petroclival region, compressing the ventral pons. The mass was surgically resected and demonstrated acute intratumoral hemorrhage. Pathologic examination was consistent with chordoma. CONCLUSION: There are few previous reports of petroclival chordomas causing acute intracranial hemorrhage. To the authors' knowledge, this is the first case of a petroclival chordoma presenting as acute intracranial hemorrhage in a pediatric patient. Although uncommon, it is important to consider chordoma when evaluating a patient of any age presenting with a hemorrhagic lesion of the clivus

GAINS ASIA: Scenarios for cost-effective control of air pollution and greenhouse gases in India

There is growing recognition that a comprehensive and combined analysis of air pollution and climate change could reveal important synergies of emission control measures. Insight into the multiple benefits of measures could make emission controls economically more viable, both in industrialized and developing countries. However, while scientific understanding on many individual aspects of air pollution and climate change has considerably increased in the last years, little attention has been paid to a holistic analysis of the interactions between both problems. The Greenhouse gas - Air pollution Interactions and Synergies (GAINS) model has been developed as a tool to identify emission control strategies that maximize synergies between the control of local air quality and the mitigation of greenhouse emissions. GAINS investigates how specific mitigation measures simultaneously influence different pollutants that threaten human health via the exposure of fine particles and ground-level ozone, damage natural vegetation and crops, contribute to climate change. In recent years the GAINS model has been implemented for India in collaboration between the International Institute for Applied Systems Analysis (IIASA) and The Energy and Resources Institute (TERI). This report presents a first analysis conducted with the GAINS model that highlights how strategies to control local air quality could be designed in such a way that co-benefits on greenhouse gas mitigation could be maximized

Systematic analysis of relationships between plasma branched-chain amino acid concentrations and cardiometabolic parameters:an association and Mendelian randomization study

Abstract Background Branched-chain amino acids (BCAAs; valine, leucine, and isoleucine) are essential amino acids that are associated with an increased risk of cardiometabolic diseases (CMD). However, there are still only limited insights into potential direct associations between BCAAs and a wide range of CMD parameters, especially those remaining after correcting for covariates and underlying causal relationships. Methods To shed light on these relationships, we systematically characterized the associations between plasma BCAA concentrations and a large panel of 537 CMD parameters (including atherosclerosis-related parameters, fat distribution, plasma cytokine concentrations and cell counts, circulating concentrations of cardiovascular-related proteins and plasma metabolites) in 1400 individuals from the Dutch population cohort LifeLines DEEP and 294 overweight individuals from the 300OB cohort. After correcting for age, sex, and BMI, we assessed associations between individual BCAAs and CMD parameters. We further assessed the underlying causality using Mendelian randomization. Results A total of 838 significant associations were detected for 409 CMD parameters. BCAAs showed both common and specific associations, with the most specific associations being detected for isoleucine. Further, we found that obesity status substantially affected the strength and direction of associations for valine, which cannot be corrected for using BMI as a covariate. Subsequent univariable Mendelian randomization (UVMR), after removing BMI-associated SNPs, identified seven significant causal relationships from four CMD traits to BCAA levels, mostly for diabetes-related parameters. However, no causal effects of BCAAs on CMD parameters were supported. Conclusions Our cross-sectional association study reports a large number of associations between BCAAs and CMD parameters. Our results highlight some specific associations for isoleucine, as well as obesity-specific effects for valine. MR-based causality analysis suggests that altered BCAA levels can be a consequence of diabetes and alteration in lipid metabolism. We found no MR evidence to support a causal role for BCAAs in CMD. These findings provide evidence to (re)evaluate the clinical importance of individual BCAAs in CMD diagnosis, prevention, and treatment

Characterization of a polychromatic microfocus X-ray fluorescence imaging setup with metallic contrast agents in a microphysiological tumor model

Introduction: Accurate diagnosis and personalized treatments involving site-targeted cancer localization, drug delivery, therapeutic strategy, and disease pathways identification, rely on a precise understanding of biomarker kinetics, drug pharmacokinetics, and mechanistic behaviour of functionalized tracers through in vitro and in vivo studies. X-ray fluorescence (XRF) computed tomography (XFCT) offers a potential alternative to current 3D imaging techniques for spatiotemporal localization of nanoparticle-tracers with high spatial resolution and sensitivity. In this work, the applicability of a benchtop cone-beam system with a polychromatic X-ray source was examined with regard to physical constraints of engineered tissue models. Methods: A tissue engineering approach based on a decellularized scaffold was used to establish a 3D breast cancer model with MDA-MB-231 cells in co-culture with primary human fibroblasts. The 3D breast cancer system, in combination with small-animal-sized phantoms, was used to demonstrate the novel integrated pre-clinical imaging approach to perform in vitro surrogate investigations and non-destructive analysis on biophantoms. These models are adopted to evaluate the functionality and optimize the setup for high-spatial-resolution, fast, and fully-3D quantitative imaging. Polychromatic X-rays from a microfocus source are used for XRF stimulation from conventional Gadolinium (Gd) and nanoparticle-based Molybdenum (MoNPs) contrast agents. Results and Discussion: The intestinal scaffold allowed the invasion of the breast cancer cells over this barrier and therefore provides a valuable tool to study metastasis formation of tumor cells from epithelial origin. The breast cancer model was well suited for the development and validation of the proposed XRF imaging, with spatial resolution under <2 mm and contrast dose in the order of a few 100 μg/mL (∼0.3 mg/mL for Gd and ∼0.5 mg/mL for MoNPs), radiation dose in the order of a few 100 cGy (280 cGy for Gd and 94 cGy for MoNPs, with a possible reduction of an order of magnitude for Gd and 67% for MoNPs), and imaging time in the order of 10 min for Gd (33 min total) and 100 min (2.8 h total) for MoNPs, approaching in vivo conform conditions for pre-clinical studies. High-resolution XFCT for tissue-engineered cancer models would be of significant interest in biomedical research and diagnostic imaging, e.g., for an increased mechanistic understanding of molecular processes in tumor formation or early cancer detection