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1.
EJIFCC ; 35(2): 120-131, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39247662

RÉSUMÉ

Background: Though paraproteinaemic interferences is a well-known phenomenon in clinical chemistry, a large-scale evaluation study involving multiple paraproteinaemic specimens on multiple platforms including multiple measurands with an aim to provide a predictive analysis, is singularly lacking. The present study aims to fill this gap in research. Material and Methods: This cross-sectional non-interventional observational study involved thirteen paraproteinaemic subjects, determined their gamma globulin characterization and measured their total bilirubin, direct bilirubin, HDL-cholesterol, calcium, inorganic phosphate, iron and unsaturated iron binding capacity (UIBC) levels on a dry chemistry platform (Vitros 350) as the established method and two wet chemistry platforms (AU5800 and Cobas 6000) as the evaluation methods. Data thus generated was analyzed for any significant variation and tested if such variation increased with decreasing albumin/ globulin ratio. Results: Significant variation between dry chemistry and wet chemistry measurements were obtained for direct bilirubin, HDL and iron on AU5800 with p-values of 0.0009, <0.0001 and 0.0466 respectively. Similarly, discrepant results were obtained on Cobas 6000 for direct bilirubin and iron, with p-values of <0.0001 and 0.0002 respectively. Additionally, UIBC measurements on AU5800 varied significantly with increasing amounts of paraprotein present in the specimen (p-value = 0.0207). Conclusion: This study emphasizes on predictive analyses to show that paraprotein interferences are fairly common on wet chemistry platforms. Evolving algorithms for monitoring of reaction curves can minimize release of erroneous results due to such interferences.

2.
J Med Biochem ; 43(4): 480-486, 2024 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-39139164

RÉSUMÉ

This case report discusses how paraproteins interfere with multiple chemistry analyses and protocols to overcome such obstacles. A serum specimen containing two monoclonal IgA (llight chain) paraproteins is subjected to a battery of tests on three wet chemistry platforms - AU5800, Cobas Pure, and Alinityci; the results were compared with those on a Vitros 350/ ECiQ dry chemistry platform. Paraprotein interference was found to affect the bilirubins, inorganic phosphate, and iron, whose repeat runs were also found to be irreproducible. Dilution with normal saline also failed to produce a satisfactory effect. Deproteinization by polyethylene glycol and dilution of the specimen with a normal serum specimen were observed to produce desirable results. Interference by IgA paraprotein on measurement of the bilirubin, phosphate, and iron in the wet chemistry system can be mitigated either by deproteinization or by dilution with normal serum.

3.
Lab Med ; 2024 Jun 11.
Article de Anglais | MEDLINE | ID: mdl-38860476

RÉSUMÉ

BACKGROUND: Interferences on chemistry and immunoassay results due to paraproteinemia may lead to erroneous diagnoses and treatment. Such interferences are difficult to recognize and even more difficult to deal with. This report describes 1 such case where multiple measurands were affected and how the interferant was overcome. CASE REPORT: Paraproteins present in an immunoglobulin (Ig)G-lambda multiple myeloma specimen interfered with results of total bilirubin, direct bilirubin, inorganic phosphate, iron, ferritin, and total thyroxine measured on 3 platforms: AU5800, Alinity ci, and cobas pure. Repeat testing upon dilution with normal saline or deproteinization by polyethylene glycol precipitation gave unsatisfactory results on some or all the affected measurands. Repeat testing after dilution of the interferant serum with a healthy serum corrected the anomalous results for all the affected measurands. CONCLUSION: Dilution of paraproteinemic serum with a healthy serum of known concentrations appears to be the most suitable method to negate the effects of paraproteinemic interferences.

4.
Sci Total Environ ; 913: 169493, 2024 Feb 25.
Article de Anglais | MEDLINE | ID: mdl-38151134

RÉSUMÉ

Pea (Pisum sativum L.), a legume, has a high nutritional content, but arsenic (As) in the agro-ecosystem poses a significant bottleneck to its yield, especially in South East Asia, by severely hampering ontogeny. The present study proposes a rhizospheric nano-remediation strategy to evade As-genotoxicity and improve crop yield using biogenic zinc-oxide nanoparticles (ZnONPs). Similar to any other source of environmental stress, As-toxicity caused rapid oxidative bursts with deterioration in morpho-physiological attributes (germination rate, shoot length, and root length decreased by 62 %, 16 %, and 14.9 % respectively in the negative control, over normal control). Reactive oxygen species (ROS) accumulation (12.8 and 9-fold increase in leaves and roots) overburdened antioxidative defense, and loss of cellular homeostasis resulted in membrane damage (82.75 % increase) and electrolyte-leakage (2.6-fold increase) in negative control. The study also reveals a significant increase in nuclear area, nuclear fragmentation, and micronuclei formation in root tip cells under As-stress, indicating severe genomic instability and increased programmed cell death (3.3-fold increase in early apoptotic cells) due to leaky plasma membrane and unrepaired DNA damage. Application of ZnONPs significantly reduced As-toxicity in peas due to its adsorption in the rhizosphere, causing diminished As-uptake and better antioxidant response. Improved phytochelatin synthesis enhanced vacuolar sequestration of arsenic, which reduced As-interference. Comparatively better flowering time (7.74-19.36 % reduction in flowering delay) with greater transcript abundance of GIGANTIA (GI), CONSTANS (CO), and FLOWERING LOCUS T (FT) genes; better photosynthetic activity (1.3-1.9-fold increased chlorophyll autofluorescence); increased pollen viability; lesser genotoxicity (decreased tail DNA in comet assay) was noticed. A maximum increase of 37.5 % in pod number and seed zinc content (1.67-fold) was observed while seed arsenic content decreased under ZnONPs treatment. However, the highest dose of ZnONPs (400 mg L-1) induced NP-toxicity in pea plants under our experimental conditions, while optimum stress-alleviation was observed up to 300 mg L-1.


Sujet(s)
Arsenic , Nanoparticules , Oxyde de zinc , Pisum sativum , Oxyde de zinc/toxicité , Arsenic/toxicité , Écosystème , Stress oxydatif , Antioxydants/métabolisme , Nanoparticules/toxicité , Zinc
5.
J Am Chem Soc ; 142(12): 5526-5530, 2020 03 25.
Article de Anglais | MEDLINE | ID: mdl-32131597

RÉSUMÉ

Planar, terpyridine-based metal complexes with the Sierpinski triangular motif and alkylated corners undergo a second self-assembly event to give megastructural Sierpinski pyramids; assembly is driven by the facile lipophilic-lipophilic association of the alkyl moieties and complementary perfect fit of the triangular building blocks. Confirmation of the 3D, pyramidal structures was verified and supported by a combination of TEM, AFM, and multiscale simulation techniques.

6.
J Org Chem ; 84(13): 8468-8480, 2019 07 05.
Article de Anglais | MEDLINE | ID: mdl-31244154

RÉSUMÉ

The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)RuII(ACN)3, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displayed excellent catalytic activity for several oxidative organic transformations including late-stage C-H functionalization of aldehydes with NH2OR to valuable primary amides in nonconventional aqueous media with excellent yield. Its diverse catalytic power was established for direct oxo-scissoring of a wide range of alkenes to furnish aldehydes and/or ketones in high yield using a low catalyst loading in the water. Its smart catalytic activity under mild conditions was validated for dioxygenation of alkynes to highly demanding labile synthons, 1,2-diketones, and/or acids. This general and sustainable catalysis was successfully employed on sugar-based substrates to obtain the chiral amides, aldehydes, and labile 1,2-diketones. The catalyst is recovered and reused with a moderate turnover. The proposed mechanistic pathway is supported by isolation of the intermediates and their characterization. This multifaceted sustainable catalysis is a unique tool, especially for late-stage functionalization, to furnish the targeted compounds through frequently used amidation and oxygenation processes in the academia and industry.

7.
Indian J Pathol Microbiol ; 62(1): 119-121, 2019.
Article de Anglais | MEDLINE | ID: mdl-30706874

RÉSUMÉ

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical tumor composed of myofibroblasts with a predilection for the head and neck, especially in the tongue and oral cavity, with a high tendency to local recurrence and metastasis, even after a long period. LGMS arising from maxillary sinus and buccal mucosa are not very common. To the best of our knowledge, only 55 cases of low-grade myofibroblastic sarcoma have been reported and only four cases of LGMS of maxillary sinus and three cases of LGMS of buccal mucosa have been reported in world literature. We report two cases of LGMS of the maxillary sinus and buccal mucosa, discussing clinical, histological, inmunohistochemical and therapeutic features.


Sujet(s)
Fibrosarcome/diagnostic , Sinus maxillaire/anatomopathologie , Muqueuse de la bouche/anatomopathologie , Myofibroblastes/anatomopathologie , Adulte , Diagnostic différentiel , Femelle , Fibrosarcome/chirurgie , Humains , Mâle , Sinus maxillaire/imagerie diagnostique , Muqueuse de la bouche/imagerie diagnostique , Récidive tumorale locale
8.
Can J Diabetes ; 41(1): 82-89, 2017 Feb.
Article de Anglais | MEDLINE | ID: mdl-27916496

RÉSUMÉ

OBJECTIVES: The present study aimed to evaluate the role of hyperlipidemia in increased formation of advanced lipoxidation end products (ALEs) and to evaluate whether there is any relationship between ALEs generation and erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity in cases of mild nonproliferative diabetic retinopathy (MNPDR). METHODS: In this study, we enrolled 100 patients with type 2 diabetes and MNPDR, 100 subjects with type 2 diabetes but without retinopathy (DNR) and 90 normal individuals without diabetes as healthy controls (HCs). Erythrocyte nicotinamide dinucleotide phosphate (NADPH), G6PD activity, serum total cholesterol, low- and high-density lipoprotein (LDL, HDL) and triglyceride levels were determined by photometric assay. Serum malondialdehyde (MDA) protein adduct and hexanoyl-lysine (HEL) were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: A robust linear relationship was observed between MDA protein adduct and LDL or cholesterol or triglyceride levels, and HEL and LDL or cholesterol or triglyceride levels in subjects with MNPDR (p=0.0001). A significant inverse association was observed between erythrocyte G6PD activity and serum MDA protein adductor HEL levels in subjects with MNPDR (p=0.0001). CONCLUSIONS: Hyperlipidemia is an important factor that is associated with increased ALEs formation in persons with MNPDR. Increased ALEs generation was associated with decreased G6PD activity and low NADPH levels in cases of MNPDR, suggesting their detrimental role in the occurrence of early NPDR.


Sujet(s)
Produits d'oxydation avancée des protéines/sang , Diabète de type 2/sang , Rétinopathie diabétique/sang , Érythrocytes/métabolisme , Glucose 6-phosphate dehydrogenase/sang , Hyperlipidémies/sang , Adulte , Marqueurs biologiques/sang , Diabète de type 2/diagnostic , Diabète de type 2/épidémiologie , Rétinopathie diabétique/diagnostic , Rétinopathie diabétique/épidémiologie , Femelle , Humains , Hyperlipidémies/diagnostic , Hyperlipidémies/épidémiologie , Mâle , Adulte d'âge moyen , Oxydoréduction
9.
Chem Commun (Camb) ; 51(64): 12851-4, 2015 Aug 18.
Article de Anglais | MEDLINE | ID: mdl-26169517

RÉSUMÉ

Mixing of metallocyclic trimers and tetramers in an exact 1 : 1.5 stoichiometry provided new supramolecular triangles in quantitative yields. Characterization of the new hetero-nuclear metallomacrocycles was achieved by (1)H, 2D-COSY, 2D-NOESY, and (13)C NMR spectroscopy, along with ESI and TWIM mass spectrometry. Gradient tandem MS (gMS(2)) provided insight into the stabilities of the binuclear structures.


Sujet(s)
Composés macrocycliques/composition chimique , Composés organométalliques/composition chimique , Pyridines/composition chimique , Modèles moléculaires , Conformation moléculaire , Polymérisation
10.
Mol Cell Biochem ; 405(1-2): 265-79, 2015 Jul.
Article de Anglais | MEDLINE | ID: mdl-25956512

RÉSUMÉ

The present study was aimed to investigate the relation between nuclear factor kappa beta (NFκB) activation and downstream up-regulation of vascular endothelial growth factor (VEGF) in diabetic retinopathy (DR). Moreover the study was intended to evaluate the role of VEGF gene single nucleotide polymorphisms (SNPs) in DR occurrence and to investigate the functional relevance of VEGF gene SNPs in terms of VEGF expression in DR. Serum level of VEGF, VEGF R1 (receptor 1), VEGF R 2 (receptor 2) and NFκB (p50/65) activity was measured by enzyme linked immune sorbent assay. Genotyping and allelic composition of different SNPs i.e., rs2010963, rs3025039, rs1570360 and rs 2071559 were investigated by Taqman SNP genotyping assay. VEGF, NFκB p50/p65, and VEGF R1 & R2 gene expressions were quantified by real time quantitative polymerase chain reaction. Increased NFκB p50/p65 activity and expressions were observed in non proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) subjects compared to type 2 diabetes mellitus without retinopathy (DNR) group. Significantly elevated levels of serum VEGF and highest VEGF expression were found among PDR subjects compared to DNR or NPDR subjects. CC genotype and C allele of rs2010963 and TT genotype and T allele of rs3025039 were significantly over represented among PDR subjects compared to DNR group. Increased activation of NFκß in NPDR and PDR subjects might involve increased up regulation of VEGF. VEGF SNPs i.e., rs2010963 C allele and rs3025039 T allele might be associated with PDR occurrence and in turn regulates VEGF expression among PDR subjects.


Sujet(s)
Rétinopathie diabétique/génétique , Facteur de transcription NF-kappa B/génétique , Polymorphisme de nucléotide simple/génétique , Régulation positive/génétique , Facteur de croissance endothéliale vasculaire de type A/génétique , Allèles , Diabète de type 2/génétique , Femelle , Génotype , Humains , Mâle , Adulte d'âge moyen , Récepteurs aux facteurs de croissance endothéliale vasculaire/génétique
11.
Angew Chem Int Ed Engl ; 53(45): 12182-5, 2014 Nov 03.
Article de Anglais | MEDLINE | ID: mdl-25214464

RÉSUMÉ

A novel terpyridine-based architecture that mimics a first-generation Sierpinski triangle has been synthesized by multicomponent assembly and features tpy-Cd(II)-tpy connectivity (tpy=terpyridine). The key terpyridine ligands were synthesized by the Suzuki cross-coupling reaction. Mixing two different terpyridine-based ligands and Cd(II) in a precise stoichiometric ratio (1:1:3) produced the desired fractal architecture in near-quantitative yield. Characterization was accomplished by NMR spectroscopy, mass spectrometry, and transmission electron microscopy.


Sujet(s)
Fractales , Spectroscopie par résonance magnétique , Microscopie électronique à transmission , Spectrométrie de masse ESI
12.
Chemistry ; 20(36): 11291-4, 2014 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-25056479

RÉSUMÉ

The design and construction of the first multicomponent stepwise assembly of a -based (tpy=terpyridine), three-dimensional, propeller-shaped trismacrocycle, 8, are reported. Key steps in the synthesis involve the preparation of a hexaterpyridinyl triptycene and its reaction with dimeric, 60°-directional, bisterpyridine-Ru(II) building blocks. Characterization includes ESI- and ESI-TWIM-MS and TEM, along with 1D and 2D (1) H NMR spectroscopy.


Sujet(s)
Composés macrocycliques/synthèse chimique , Composés organométalliques/synthèse chimique , Pyridines/synthèse chimique , Ruthénium/composition chimique , Composés macrocycliques/composition chimique , Modèles moléculaires , Composés organométalliques/composition chimique , Pyridines/composition chimique
13.
Indian J Clin Biochem ; 29(2): 189-95, 2014 Apr.
Article de Anglais | MEDLINE | ID: mdl-24757301

RÉSUMÉ

Although 3rd generation TSH assays are the most widely used immunoassays, credible comparison studies, specially involving Indian sub-populations are practically non-existent. To compare the TSH measurements between chemiluminescence (Architect) and electrochemiluminescence (Cobas) inmmunoassays in an urban ambulatory Indian population. 1,615 subjects were selected randomly from the usual laboratory workflow, their TSH measured in Architect and Cobas and the paired data thus generated were statistically analysed. TSH values of Cobas were observed to be higher than the Architect values by 28.7 %, with a significant proportional difference between the two, but majority of the Cobas values (above 90 %) were within the limits of agreement with Architect values. In situations where both the instruments are in use simultaneously, a standardization of the methods is imperative, in larger interest of the patient populace.

14.
Clin Chim Acta ; 423: 130-4, 2013 Aug 23.
Article de Anglais | MEDLINE | ID: mdl-23643931

RÉSUMÉ

INTRODUCTION: Although TSH measurement by electrochemiluminescence immunoassay has become commonplace in India, significant discrepancy has been observed on interpretation of the test results when the manufacturer supplied biological reference interval (BRI) criteria were applied. This report determined whether the manufacturer's BRI (Roche Cobas) is transferable to the Indian population. METHODS: Three hundred seventy-eight age- and sex-matched healthy subjects were selected from an urban Indian population. TSH reference measurements were acquired, and the reference data were statistically analysed. RESULTS: BRI of the Indian urban reference population was determined by non-parametric means. BRI was found to be 1.134 to 7.280µIU/ml. CONCLUSION: BRI thus calculated was found to be significantly different from that mentioned by the manufacturer (0.27 to 4.20µIU/ml), which, needless to mention, has profound clinical implications in this part of the globe.


Sujet(s)
Dosage immunologique/normes , Thyréostimuline/sang , Adulte , Femelle , Humains , Inde , Luminescence , Mâle , Adulte d'âge moyen , Valeurs de référence , Jeune adulte
15.
EJIFCC ; 24(2): 61-7, 2013 Jul.
Article de Anglais | MEDLINE | ID: mdl-27683439

RÉSUMÉ

BACKGROUND: The validity of the entire renal function tests as a diagnostic tool depends substantially on the Biological Reference Interval (BRI) of urea. Establishment of BRI of urea is difficult partly because exclusion criteria for selection of reference data are quite rigid and partly due to the compartmentalization considerations regarding age and sex of the reference individuals. Moreover, construction of Biological Reference Curve (BRC) of urea is imperative to highlight the partitioning requirements. MATERIALS AND METHODS: This a priori study examines the data collected by measuring serum urea of 3202 age and sex matched individuals, aged between 1 and 80 years, by a kinetic UV Urease/GLDH method on a Roche Cobas 6000 auto-analyzer. RESULTS: Mann-Whitney U test of the reference data confirmed the partitioning requirement by both age and sex. Further statistical analysis revealed the incompatibility of the data for a proposed parametric model. Hence the data was non-parametrically analysed. BRI was found to be identical for both sexes till the 2(nd) decade, and the BRI for males increased progressively 6(th) decade onwards. Four non-parametric models were postulated for construction of BRC: Gaussian kernel, double kernel, local mean and local constant, of which the last one generated the best-fitting curves. CONCLUSION: Clinical decision making should become easier and diagnostic implications of renal function tests should become more meaningful if this BRI is followed and the BRC is used as a desktop tool in conjunction with similar data for serum creatinine.

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