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1.
Molecules ; 28(24)2023 Dec 07.
Article En | MEDLINE | ID: mdl-38138471

Heparin, a highly sulfated glycosaminoglycan, is a naturally occurring anticoagulant that plays a vital role in various physiological processes. The remarkable structural complexity of heparin, consisting of repeating disaccharide units, makes it a crucial molecule for the development of commercial drugs in the pharmaceutical industry. Over the past few decades, significant progress has been made in the development of cost-effective adsorbents specifically designed for the adsorption of heparin from porcine intestinal mucosa. This advancement has been driven by the need for efficient and scalable methods to extract heparin from natural sources. In this study, we investigated the use of cationic ammonium-functionalized diatomaceous earth, featuring enhanced porosity, larger surface area, and higher thermal stability, to maximize the isolated heparin recovery. Our results showed that the higher cationic density and less bulky quaternary modified diatomaceous earth (QDADE) could adsorb up to 16.3 mg·g-1 (31%) of heparin from the real mucosa samples. Additionally, we explored the conditions of the adsorbent surface for recovery of the heparin molecule and optimized various factors, such as temperature and pH, to optimize the heparin uptake. This is the introductory account of the implementation of modified diatomaceous earth with quaternary amines for heparin capture.


Diatomaceous Earth , Heparin , Animals , Swine , Diatomaceous Earth/chemistry , Anticoagulants , Temperature , Intestinal Mucosa
2.
Genes (Basel) ; 14(7)2023 06 24.
Article En | MEDLINE | ID: mdl-37510237

A 60-year-old male with hypertrophic cardiomyopathy, conduction disorders, post-COVID-19 myopericarditis and heart failure was admitted to the hospital's cardiology department. Blood tests revealed an increase in CPK activity, troponin T elevation and high titers of anticardiac antibodies. Whole exome sequencing showed the presence of the pathogenic variant NM_213599:c.2272C>T of the ANO5 gene. Results of the skeletal muscle biopsy excluded the diagnosis of systemic amyloidosis. Microscopy of the muscle fragment demonstrated sclerosis of the perimysium, moderate lymphoid infiltration, sclerosis of the microvessels, dystrophic changes and a lack of cross striations in the muscle fibers. Hypertrophy of the LV with a low contractile ability, atrial fibrillation, weakness of the distal skeletal muscles and increased plasma CPK activity and the results of the skeletal muscle biopsy suggested a diagnosis of a late form of distal myopathy (Miyoshi-like distal myopathy, MMD3). Post-COVID-19 myopericarditis, for which genetically modified myocardium could serve as a favorable background, caused heart failure decompensation.


COVID-19 , Cardiomyopathy, Hypertrophic , Distal Myopathies , Heart Failure , Myocarditis , Male , Humans , Middle Aged , Distal Myopathies/diagnosis , Distal Myopathies/genetics , Distal Myopathies/pathology , Sclerosis/pathology , Anoctamins/genetics , Chloride Channels/genetics , Mutation , COVID-19/complications , COVID-19/genetics , COVID-19/pathology , Muscle, Skeletal/pathology , Cardiomyopathy, Hypertrophic/complications , Cardiomyopathy, Hypertrophic/genetics , Cardiomyopathy, Hypertrophic/pathology , Heart Failure/genetics , Heart Failure/pathology
3.
Bioengineering (Basel) ; 9(11)2022 Oct 23.
Article En | MEDLINE | ID: mdl-36354517

Heparin, usually isolated from porcine intestinal mucosa, is an active pharmaceutical ingredient of great material value. Traditionally, diverse types of commercial resins were employed as an adsorbent for heparin retrieval from biological samples. However, more recent years have encouraged the advent of new cost-effective adsorbents to achieve enhanced heparin retrieval. Inexpensive cationic ammonium-functionalized silica gels, monodispersed with larger surface area, porosity, and higher thermal stability, were chosen to evaluate the heparin recovery yield from porcine intestinal mucosa. We demonstrated that higher positively charged and less bulky quaternary modified silica gel (e.g., QDASi) could adsorb ~28% (14.7 mg g-1) heparin from the real samples. In addition, we also determined suitable surface conditions for the heparin molecule adsorption by mechanistic studies and optimized different variables, such as pH, temperature, etc., to improve the heparin adsorption. This is going to be the first reported study on the usage of quaternary amine-functionalized silica gel for HEP uptake.

4.
Photochem Photobiol ; 95(1): 154-162, 2019 01.
Article En | MEDLINE | ID: mdl-30103294

Laser flash photolysis of ketone 1 in argon-saturated methanol yields triplet biradical 1BR (τ = 63 ns) that intersystem crosses to form photoenols Z-1P (λmax = 350 nm, τ ~ 10 µs) and E-1P (λmax = 350 nm, τ > 6 ms). The activation barrier for Z-1P re-forming ketone 1 through a 1,5-H shift was determined as 7.7 ± 0.3 kcal mol-1 . In contrast, for ketone 2, which has a less sterically hindered carbonyl moiety, laser flash photolysis in argon-saturated methanol revealed the formation of biradical 2BR (λmax = 330 nm, τ ~ 303 ns) that intersystem crosses to form photoenol E-2P (λmax = 350 nm, τ > 42 µs), but photoenol Z-2P was not detected. However, in more viscous basic H-bond acceptor (BHA) solvent, such as hexamethylphosphoramide, triplet 2BR intersystem crosses to form both Z-2P (λmax = 370 nm, τ ~ 1.5 µs) and E-2P. Thus, laser flash photolysis of ketone 2 in methanol reveals that intersystem crossing from 2BR to form Z-2P is slower than the 1,5-H shift of Z-2P, whereas in viscous BHA solvents, the 1,5-H shift becomes slower than the intersystem crossing from 2BR to Z-2P. Density functional theory and coupled cluster calculations were performed to support the reaction mechanisms for photoenolization of ketones 1 and 2.

5.
Org Biomol Chem ; 15(35): 7380-7386, 2017 Sep 13.
Article En | MEDLINE | ID: mdl-28848985

Irradiation of nanocrystals of azide 1 results in a solid-to-solid reaction that forms imine 2 in high chemical yield. In contrast, solution photolysis of azide 1 yields a mixture of products, with 7 as the major one. Laser flash photolysis (LFP) of a nanocrystalline suspension of azide 1 in water shows selective formation of benzoyl radical 4 (λmax ∼ 400 nm), which is short-lived (τ = 833 ns) as it intersystem crosses to form imine 2. In comparison, LFP of azide 1 in methanol reveals the formation of triplet alkylnitrene 10 (λmax ∼ 340 nm). The selectivity observed in the solid-state is related to stabilization of the triplet ketone with (n,π*) configuration by the crystal lattice, which results in α-cleavage being favored over triplet energy transfer to the azido chromophore. Both the solid-state and solution reaction mechanisms are further supported by density functional theory calculations. Thus, laser flash photolysis has been used to effectively elucidate the medium dependent reaction mechanisms of azide 1.

6.
Photochem Photobiol ; 92(3): 388-98, 2016 05.
Article En | MEDLINE | ID: mdl-27061950

Photolysis of ester 1 in argon-saturated methanol and acetonitrile does not produce any product, whereas irradiation of 1 in oxygen-saturated methanol yields peroxide 2. Laser flash photolysis studies demonstrate that 1 undergoes intramolecular H atom abstraction to form biradical 3 (λmax ~340 nm), which intersystem crosses to form photoenols Z-4 and E-4 (λmax ~380 nm). Photoenols 4 decay by regenerating ester 1. With the aid of density functional theory calculations, it was concluded the photoenol E-4 does not undergo spontaneous lactonization or electrocyclic ring closure because the transition state barriers for these reactions are too large to compete with reketonization of E-4 to form 1.

7.
Vet Res Commun ; 38(2): 115-22, 2014 Jun.
Article En | MEDLINE | ID: mdl-24477841

The effect of immunization on systemic and cutaneous mucosal immune responses of fish and their possible relation with protection has not been fully assessed. In this study, healthy catla (Catla catla) were immunized against Edwardsiella tarda using two antigenic preparations namely, whole cell bacterin (B) and bacterin mixed with Freund's complete adjuvant in a 1:1 (v/v) ratio (B+A) followed by a booster dose after 3 weeks of first injection. Different systemic and cutaneous mucosal immune responses were measured at weekly interval upto 8th week post vaccination (pv). Fish were challenged 8 weeks pv with live E. tarda to study vaccine induced protection. The result showed that although there were strong systemic as well as mucosal immune responses, particularly after booster dose, the challenge produced low to moderate protection in terms of relative percent survival (RPS). The maximum RPS (50 %) was recorded in the adjuvanted bacterin group after 8 weeks pv. Low to moderate protection after challenge, which may be attributed to the intracellular nature of E. tarda and/or use of crude antigenic preparation, accounts for new strategy to be developed for immunization programme against such intracellular pathogen. The results collectively suggest possible involvement of systemic as well as mucosal immune responses in inducing protective immunity in catla.


Bacterial Vaccines/immunology , Enterobacteriaceae Infections/veterinary , Fish Diseases/immunology , Immunity, Humoral/immunology , Immunity, Mucosal/immunology , Immunization/veterinary , Animals , Antibodies, Bacterial/blood , Cell Proliferation , Cyprinidae/immunology , Edwardsiella tarda/immunology , Enterobacteriaceae Infections/mortality , Enterobacteriaceae Infections/prevention & control , Enzymes/blood , Fish Diseases/mortality , Fish Diseases/prevention & control , Leukocytes/cytology , Macrophage-Activating Factors/immunology , Mucus/chemistry , Mucus/enzymology , Muramidase/metabolism , Peroxidase/metabolism , Survival Analysis
8.
Int J Biol Macromol ; 63: 107-13, 2014 Feb.
Article En | MEDLINE | ID: mdl-24184731

Dityrosine cross-linking is considered to be one of the major reasons behind natural protein dimerization. Reports have shown that dimers of Ribonuclease A prepared by several methods exhibit reduced ribonucleolytic activity compared to the native monomer. Here in the present report, a detail investigation has been carried out to determine the effect of dityrosine cross-linking of Ribonuclease A on its ribonucleolytic activity. We have also studied the inhibitory property of natural, competitive and noncompetitive inhibitors on the catalytic activity of the dimer. The dimer was prepared by photo irradiation of Ribonuclease A using riboflavin as a photo sensitizer followed by separation using size exclusion chromatography. The dimer has been characterized via gel electrophoresis and various spectroscopic techniques. Experimental findings suggest that the synthesized dityrosine cross-linked dimer of Ribonuclease A exhibits reduced ribonucleolytic activity in comparison with the monomeric form both in the presence and absence of the inhibitors.


Enzyme Inhibitors/pharmacology , Ribonuclease, Pancreatic/chemistry , Tyrosine/analogs & derivatives , Catalysis/drug effects , Chromatography, Gel , Cross-Linking Reagents/chemistry , Dimerization , Polymers/chemistry , Riboflavin/chemistry , Ribonuclease, Pancreatic/antagonists & inhibitors , Ribonuclease, Pancreatic/isolation & purification , Tyrosine/chemistry , Tyrosine/pharmacology
9.
Fish Shellfish Immunol ; 35(5): 1547-53, 2013 Nov.
Article En | MEDLINE | ID: mdl-24012512

Effects of dietary administration of Bacillus amyloliquefaciens FPTB16 on systemic and mucosal immunity and disease resistance of catla (Catla catla) against Edwardsiella tarda infection were evaluated in the present study. The laboratory maintained B. amyloliquefaciens was used to study antagonistic activity against fish pathogenic bacteria by agar well diffusion assay. Healthy catla were challenged by this bacterium for determination of its safety. For preparation of probiotic supplemented diet, the bacteria were added to the basal diet (control) at three different inclusion levels i.e., 1 × 10(9), 1 × 10(8) and 1 × 10(7) CFU/g diet. Fish (weight 25-30 g) were fed with these diets and various immune parameters and disease resistance study were conducted at 4 weeks and 8 weeks post-feeding. The bacterial antagonism study showed inhibition zone against E. tarda, Aeromonas hydrophila, Vibrio parahaemolyticus and V. harveyi. B. amyloliquefaciens was harmless to catla as neither mortalities nor morbidities were observed after the challenge. Study of different systemic and mucosal immunological parameters viz. superoxide anion production and nitric oxide production, myeloperoxidase content, lysozyme activity and total protein content showed significant enhancement (p < 0.05) in fish fed with 10(8) and 10(9) CFU/g B. amyloliquefaciens at both time points with the highest values observed in case of 10(9) CFU/g. For fish fed with 10(7) CFU/g B. amyloliquefaciens, all the parameters showed significant enhancement (p < 0.05) at both time points except the lysozyme activity of serum at 8 weeks. Diet containing 10(8) and 10(9) CFU/g B. amyloliquefaciens significantly enhanced (p < 0.05) the resistance of catla against bacterial challenge at both time points. These results collectively suggest that B. amyloliquefaciens is a potential probiotic species and can be used in aquaculture to improve health status and disease resistance with an optimal dietary supplementation of 10(9) CFU/g.


Bacillus/chemistry , Cyprinidae/immunology , Disease Resistance/drug effects , Immunity, Mucosal/drug effects , Probiotics/pharmacology , Animals , Aquaculture/methods , Dietary Supplements , Disease Resistance/immunology , Dose-Response Relationship, Drug , Head Kidney/immunology , Immunity, Mucosal/immunology , Muramidase/metabolism , Nitric Oxide/metabolism , Peroxidase/metabolism , Probiotics/administration & dosage , Superoxides/metabolism
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