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A modified lateral flow assay, using serum, for the rapid identification of human and bovine cysticercosis in the absence of false positives.

BACKGROUND: Previously we reported the use of a monoclonal antibody-based (HP10) antigen (Ag) detection lateral flow assay (LFA) for the diagnosis of extraparenchymal neurocysticercosis (EP-NCC). The assay performed well when used with cerebrospinal fluid (CSF) samples but not with their paired serum samples, due to false-positive reactions in some known negative control cases. METHODS: Our novel modification involves pretreatment of serum samples using a combination of sodium deoxycholate and dithiothreitol. RESULTS: The modification overcomes the problem of false positives when using negat…

Metabolic activation of pentachlorophenol: TCBQ as a potent inhibitor of gonadal steroidogenesis via 3β-hydroxysteroid dehydrogenase NAD+ binding-site thiolalkylation.

Pentachlorophenol (PCP) is a pesticide and persistent endocrine disruptor. This study examined how PCP and its metabolite tetrachloro-1,4-be … d to the enzyme's steroid/NAD⁺ site, with TCBQ covalently attaching to Cys123 via Michael addition. Dithiothreitol (DTT) partially reversed TCBQ's inhibition but not PCP's, suggesting differing mechanisms. Findings indicate PCP's metabolic activation to TCBQ drives its stronger endocrine-disrupting effects, highlighting TCBQ's role as a potent 3β-HSD inhibitor i …

Адаптация эукариот-подобных PRS к прокариот-подобным tRNAPro.

Синтеты Проли-ТРНА (ПРОРС) уникальны среди аминоачил-тРНК (ААРС) two различные структурные архитектуры различных организмов: прокариота-подобные (П-тип) и эукариоте/археон-подобные (Е-тип). Интересно, что Бакиллус Тюрингьенси гавань обоих типов, сосуществует P-тип (BtProRS1) и E-тип PRS (BtProRS2). Несмотря на свои различия, оба фермента формально выражаются и функционируют в vivo. По аналогии с BtProRS1, BtPRS2 выборочно заряжает TRNAPro типа P и демонстрирует более высокий допуск к галоугинону, чем каноническая PRS. Однако эти two Изозимы признают основные идентификационные элементы типа P t

Совпадение в аннотации оригинала
Prolyl-tRNA synthetases (ProRSs) are unique among aminoacyl-tRNA synthetases (aaRSs) in having two distinct structural architectures across … BtProRS2 exhibits significantly higher tolerance to stresses (such as heat, hydrogen peroxide, and dithiothreitol) than BtProRS1 does. This study underscores how an E-type ProRS adapts to a P-type tRNAPro and how it may contribute to the bacterium's survival under stress conditions.

Metabolic Status and Morphological Changes of Astrocytes under Reductive Stress in vitro: Neural Network Analysis.

Reductive stress caused by excessive accumulation of reducing equivalents (NADH, NADPH, glutathione), is increasingly recognized as a pathogenetic factor at the early stages of neurodegenerative diseases. However, its impact on the morphofunctional properties of astrocytes remains poorly understood. We performed the first comprehensive quantitative assessment of biochemical and morphological changes in cultured primary rat astrocytes under chronic reductive stress modeled using dithiothreitol (DTT, 500 μM, 24 h). To enable morphometric analysis of live, unstained cells, we developed and traine…

Quantification of residual DTT by high-performance anion-exchange chromatography coupled with pulsed amperometric detection.

VLP (virus-like particle) have proven to be safer vaccine candidates compared to live-attenuated or inactivated viral vaccines. As part of the manufacturing process of VLP-based vaccines, dithiothreitol (DTT) and other reducing agents are commonly used in the disassembly of VLPs, followed by a subsequent reassembly process for the removal of the added reducing agents. This disassembly and reassembly processes improve VLP integrity, stability and immunoreactivity. In the manufacture of VLPs, it is essential that DTT removal is ensured since it is a highly toxic substance. Residual DTT content h…

Metal binding and oligomerization properties of FurC (PerR) from Anabaena sp. PCC7120: an additional layer of regulation?

Metal and redox homeostasis in cyanobacteria is tightly controlled to preserve the photosynthetic machinery from mismetallation and minimize … omerization of dimers occurs upon oxidation of thiols by H2O2 or diamide and can be reversed by 1,4-Dithiothreitol (DTT). Irreversible inactivation of the regulator occurs by metal catalyzed oxidation promoted by ferrous iron. However, inactivation upon oxidation with H2O2 in the absence of iron was reverted by addition of DTT. Comparison of models for FurC: Zn …

Changes in cellular infrastructure after induced endoplasmic reticulum stress in Moniliophthora perniciosa.

Moniliophthora perniciosa is a basidiomycete fungus that causes witches' broom disease in Theobroma cacao We analyzed the morphology and survival of fungal hyphae and endoplasmic reticulum (ER) remodeling in either glucose- or glycerol-grown M. perniciosa after treatment with ER stress-inducing chemicals dithiothreitol (DTT) or tunicamycin (TM). Changes in intracellular redox potential can cause endoplasmic reticulum (ER) stress due to diminished efficiency in protein folding that could in turn reduce cell survival. Such stress diminishes protein-folding efficiency that could in turn reduce ce…

von Willebrand factor binding to heparin in various types of von Willebrand disease.

INTRODUCTION: The purpose was to study von Willebrand factor (vWF) binding to heparin in different types of von Willebrand disease (vWD). MATERIALS AND METHODS: Plasma samples from 92 patients were representative of most vWD subtypes as they included 13 type 1, ten type 2N, 27 type 2A, 23 type 2B, and 19 type 2M patients. We selected assay conditions suitable for the screening of plasma vWF concentrations as low as 15 U/dl vWF:Ag. We determined the range of vWF concentrations in plasma where the percentage of (125)I-MAb/vWF complexes bound to heparin-agarose beads was constant. This range of

Two distinct uptake mechanisms for ascorbate and dehydroascorbate in human lymphoblasts and their interaction with glucose.

In diabetes, a major cause of mortality is from cardiovascular causes, and low levels of antioxidants such as vitamin C have been associated with such complications. Leucocyte ascorbic acid status can reflect total body stores but the mechanisms that mediate the uptake of ascorbic acid (AA) or dehydroascorbic acid (DHA) in human lymphoid cells are undefined. We have investigated the uptake of AA and DHA with mass assays in human lymphoblasts by using HPLC, with precautions to prevent the oxidation of AA and to take into account the instability of DHA in buffers. Human lymphoblasts exhibit dist

The in vitro biosynthesis of taxiphyllin and the channeling of intermediates in Triglochin maritima.

The in vitro biosynthesis of the cyanogenic glucoside taxiphyllin has recently been demonstrated in Triglochin maritima (Hösel, W., and Nahrstedt, A. (1980) Arch. Biochem. Biophys. 203, 753-757). We have now studied in more detail the multistep conversion of tyrosine into p-hydroxymandelonitrile, the immediate precursor of taxiphyllin, catalyzed by microsomes isolated from dark-grown seedlings. The biosynthetic pathway involves N-hydroxytyrosine, p-hydroxyphenylacetaldoxime, and p-hydroxyphenylacetonitrile. In marked contrast to an analogous pathway in Sorghum bicolor, p-hydroxyphenylacetonitr

Effect of thiol derivatives on mixed mucus and blood clots in vitro.

The disintegrating effect of three reducing thiol derivatives: [sodium mercaptoethane sulphonate (Mesna), N-acetyl-L-cysteine (NAC) and dithio-1,4-threitol (DTT)] was investigated in vitro upon blood clots formed in the absence or in the presence of tracheobronchial secretions and compared with the effect of iso-osmotic saline solution. The amounts of haemoglobin released from the clots after 30 min incubation and the initial rates of haemoglobin release were compared for the different products at different concentrations. All three reducing agents showed some ability to disintegrate mixed clo

An improved HPLC method for the quantitation of 6-mercaptopurine and its metabolites in red blood cells.

A procedure is described for the rapid determination of the intra-erythrocyte concentration of 6-mercaptopurine (6-MP) and its metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP). Erythrocytes (8 x 10(8) cells) in 350 microl Hanks solution containing 7.5 mg dithiothreitol were treated with 50 microl 70% perchloric acid. The precipitate was removed by centrifugation (13,000 g) and the supernatant hydrolyzed at 100 degrees C for 45 min. After cooling, 100 microl was analyzed directly by HPLC using a Radialpack Resolve C18 column eluted with methanol-water (7.5:92.5,…

Protective role of aryl and alkyl diselenides on lipid peroxidation.

The concept that selenium-containing molecules may be better nucleophiles (and therefore antioxidants) than classical antioxidants has led to the design of synthetic organoselenium compounds. In the present study we appraised the antioxidant potential, thiol peroxidase activity, and rate of dithiotreitol and reduced glutathione oxidation of simple organodiselenide compounds in rats and mice. The present results demonstrate that alkyl and aryl diselenides are antioxidant compounds. We verified that the substitution on the aromatic moiety of diphenyl diselenide or the replacement of on aryl grou

The Mycobacterium xenopi GyrA protein splicing element: characterization of a minimal intein.

The 198-amino-acid in-frame insertion in the gyrA gene of Mycobacterium xenopi is the smallest known naturally occurring active protein splicing element (intein). Comparison with other mycobacterial gyrA inteins suggests that the M. xenopi intein underwent a complex series of events including (i) removal of 222 amino acids that encompass most of the central intein domain, and (ii) addition of a linker of unrelated residues. This naturally occurring genetic rearrangement is a representative characteristic of the taxon. The deletion process removes the conserved motifs involved in homing endonuc

Immune modulation by Coxiella burnetii: characterization of a phase I immunosuppressive complex differentially expressed among strains.

Coxiella burnetii, the etiological agent of Q fever, possesses immunomodulatory activity which positively and negatively regulates host immune responses. We wish to determine the Coxiella strain differences and the chemical nature of cellular components suppressing lymphocyte responsiveness. The bacterial components responsible for the immunomodulatory activity are associated with phase I cells. In its natural state, the phase I cell-associated, immunosuppressive complex (ISC) was resistant to chemical and enzymatic treatment. The ISC was inactivated and rendered accessible by chloroform-metha

Design, synthesis and antitumor activity of celastrol thiazole derivatives with enhanced covalent binding capacity.

Celastrol (CEL), a natural product, has attracted great attention because of its remarkable antitumor potential. Its unique quinone methide … ther pharmacological studies showed that compound 28 exhibited more extensive and stable binding to dithiothreitol (DTT, a thiol-containing model molecule) than CEL, which might account for its enhanced antiproliferative activity. Moreover, compound 28 effectively induced apoptosis in MDA-MB-231 cells and arrested cells in the G2/M phase. In conclusion, compound …

An ultraviolet-driven rescue pathway for oxidative stress to eye lens protein human gamma-D crystallin.

Human gamma-D crystallin (HGD) is a major constituent of the eye lens. Aggregation of HGD contributes to cataract formation, the leading cau … t-translational modifications. After aging for nine months in the absence of light, a thiol-adduct (dithiothreitol) modifying surface cysteines is observed by low-dose SSX. This is shown to be UV-labile in an acutely light-exposed structure. This suggests a mechanism by which a major source of crystallin damage, UV, may also act as a rescuing factor in a finely …

Acrylate-Based PEG Hydrogels with Ultrafast Biodegradability for 3D Cell Culture.

Poly(ethylene glycol) (PEG)-based hydrogels are particularly challenging to degrade, which hinders efficient cell harvesting within the gel … s) by up to 193.2%. Importantly, DS junctions can be easily cleaved into short primary chains using dithiothreitol (DTT), triggering ultrafast degradation of PEG-DS/Gel-SH hydrogels within 2 min under mild conditions and release of the encapsulated BMSCs. This study establishes a novel strategy to enhance the degradation of acrylate-based PEG hydrogels for three …

Characteristics of a Novel Manganese Superoxide Dismutase of a Hadal Sea Cucumber (Paelopatides sp.) from the Mariana Trench.

A novel, cold-adapted, and acid-base stable manganese superoxide dismutase (Ps-Mn-SOD) was cloned from hadal sea cucumber Paelopatides sp. T … -Mn-SOD was relatively stable in divalent metal ion and other chemicals, such as β-mercaptoethanol, dithiothreitol, Tween 20, Triton X-100, and Chaps. Furthermore, the enzyme showed striking stability in 5 M urea or 4 M guanidine hydrochloride, resisted digestion by proteases, and tolerated a high hydrostatic pressure of 100 MPa. The resistance of Ps-Mn-SOD agai …