178 research outputs found
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 CâF 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
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 athleteâs 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 Ă 10âcm 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 400âmg 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
Genetic and Microbial Associations to Plasma and Fecal Bile Acids in Obesity Relate to Plasma Lipids and Liver Fat Content
Bile acids (BAs) have been implicated in obesity-related conditions such as NAFLD and hyperlipidemia. Different human BAs exert variable biological activities. Chen et al. define genetic and microbial associations to plasma and fecal BA concentrations and composition in persons with obesity and establish their relationships with liver fat and lipid phenotypes
Surface PEGylation suppresses pulmonary effects of CuO in allergen-induced lung inflammation
BACKGROUND: Copper oxide (CuO) nanomaterials are used in a wide range of industrial and commercial applications. These materials can be hazardous, especially if they are inhaled. As a result, the pulmonary effects of CuO nanomaterials have been studied in healthy subjects but limited knowledge exists today about their effects on lungs with allergic airway inflammation (AAI). The objective of this study was to investigate how pristine CuO modulates allergic lung inflammation and whether surface modifications can influence its reactivity. CuO and its carboxylated (CuO COOH), methylaminated (CuO NH3) and PEGylated (CuO PEG) derivatives were administered here on four consecutive days via oropharyngeal aspiration in a mouse model of AAI. Standard genome-wide gene expression profiling as well as conventional histopathological and immunological methods were used to investigate the modulatory effects of the nanomaterials on both healthy and compromised immune system. RESULTS: Our data demonstrates that although CuO materials did not considerably influence hallmarks of allergic airway inflammation, the materials exacerbated the existing lung inflammation by eliciting dramatic pulmonary neutrophilia. Transcriptomic analysis showed that CuO, CuO COOH and CuO NH3 commonly enriched neutrophil-related biological processes, especially in healthy mice. In sharp contrast, CuO PEG had a significantly lower potential in triggering changes in lungs of healthy and allergic mice revealing that surface PEGylation suppresses the effects triggered by the pristine material. CONCLUSIONS: CuO as well as its functionalized forms worsen allergic airway inflammation by causing neutrophilia in the lungs, however, our results also show that surface PEGylation can be a promising approach for inhibiting the effects of pristine CuO. Our study provides information for health and safety assessment of modified CuO materials, and it can be useful in the development of nanomedical applications
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