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1.
Int J Mol Sci ; 25(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38732139

RESUMEN

The plant-derived α-linolenic acid (ALA) is an essential n-3 acid highly susceptible to oxidation, present in oils of flaxseeds, walnuts, canola, perilla, soy, and chia. After ingestion, it can be incorporated in to body lipid pools (particularly triglycerides and phospholipid membranes), and then endogenously metabolized through desaturation, elongation, and peroxisome oxidation to eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), with a very limited efficiency (particularly for DHA), beta-oxidized as an energy source, or directly metabolized to C18-oxilipins. At this moment, data in the literature about the effects of ALA supplementation on metabolic syndrome (MetS) in humans are inconsistent, indicating no effects or some positive effects on all MetS components (abdominal obesity, dyslipidemia, impaired insulin sensitivity and glucoregulation, blood pressure, and liver steatosis). The major effects of ALA on MetS seem to be through its conversion to more potent EPA and DHA, the impact on the n-3/n-6 ratio, and the consecutive effects on the formation of oxylipins and endocannabinoids, inflammation, insulin sensitivity, and insulin secretion, as well as adipocyte and hepatocytes function. It is important to distinguish the direct effects of ALA from the effects of EPA and DHA metabolites. This review summarizes the most recent findings on this topic and discusses the possible mechanisms.


Asunto(s)
Síndrome Metabólico , Ácido alfa-Linolénico , Síndrome Metabólico/metabolismo , Humanos , Ácido alfa-Linolénico/metabolismo , Ácido alfa-Linolénico/administración & dosificación , Animales , Ácidos Grasos Insaturados/metabolismo , Suplementos Dietéticos , Resistencia a la Insulina
2.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38397014

RESUMEN

The binding of ubiquitous serum ligands (free fatty acids) to human serum albumin (HSA) or its glycation can affect thiol group reactivity, thus influencing its antioxidant activity. The effects of stearic acid (SA) and glucose binding on HSA structural changes and thiol group content and reactivity were monitored by fluoroscopy and the Ellman method during a 14-day incubation in molar ratios to HSA that mimic pathophysiological conditions. Upon incubation with 5 mM glucose, HSA glycation was the same as HSA without it, in three different HSA:SA molar ratios (HSA:SA-1:1-2-4). The protective effect of SA on the antioxidant property of HSA under different glucose regimes (5-10-20 mM) was significantly affected by molar ratios of HSA:SA. Thiol reactivity was fully restored with 5-20 mM glucose at a 1:1 HSA:SA ratio, while the highest thiol content recovery was in pathological glucose regimes at a 1:1 HSA:SA ratio. The SA affinity for HSA increased significantly (1.5- and 1.3-fold, p < 0.01) with 5 and 10 mM glucose compared to the control. These results deepen the knowledge about the possible regulation of the antioxidant role of HSA in diabetes and other pathophysiological conditions and enable the design of future HSA-drug studies which, in turn, is important for clinicians when designing information-based treatments.


Asunto(s)
Albúmina Sérica Humana , Compuestos de Sulfhidrilo , Humanos , Albúmina Sérica Humana/metabolismo , Compuestos de Sulfhidrilo/química , Antioxidantes/farmacología , Antioxidantes/metabolismo , Ácidos Grasos/metabolismo , Albúmina Sérica/metabolismo , Unión Proteica
3.
Int J Mol Sci ; 25(1)2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38203504

RESUMEN

In this study, a cost-effective sandwich ELISA test, based on polyclonal antibodies, for routine quantification SARS-CoV-2 nucleocapsid (N) protein was developed. The recombinant N protein was produced and used for the production of mice and rabbit antisera. Polyclonal N protein-specific antibodies served as capture and detection antibodies. The prototype ELISA has LOD 0.93 ng/mL and LOQ 5.3 ng/mL, with a linear range of 1.52-48.83 ng/mL. N protein heat pretreatment (56 °C, 1 h) decreased, while pretreatment with 1% Triton X-100 increased analytical ELISA sensitivity. The diagnostic specificity of ELISA was 100% (95% CI, 91.19-100.00%) and sensitivity was 52.94% (95% CI, 35.13-70.22%) compared to rtRT-PCR (Ct < 40). Profoundly higher sensitivity was obtained using patient samples mostly containing Wuhan-similar variants (Wuhan, alpha, and delta), 62.50% (95% CI, 40.59 to 81.20%), in comparison to samples mostly containing Wuhan-distant variants (Omicron) 30.00% (6.67-65.25%). The developed product has relatively high diagnostic sensitivity in relation to its analytical sensitivity due to the usage of polyclonal antibodies from two species, providing a wide repertoire of antibodies against multiple N protein epitopes. Moreover, the fast, simple, and inexpensive production of polyclonal antibodies, as the most expensive assay components, would result in affordable antigen tests.


Asunto(s)
COVID-19 , Proteínas de la Nucleocápside , Animales , Humanos , Conejos , SARS-CoV-2 , COVID-19/diagnóstico , Anticuerpos , Ensayo de Inmunoadsorción Enzimática
4.
World J Surg ; 46(10): 2416-2422, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35798991

RESUMEN

BACKGROUND: Post-thyroidectomy bleeding is rare, but potentially life-threatening complication. Early recognition with immediate intervention is crucial for the management of this complication. Therefore, it is very important to identify possible risk factors of postoperative hemorrhage as well as timing of postoperative hematoma occurrence. METHODS: Retrospective review of 6938 patients undergoing thyroidectomy in a tertiary center in a ten year period (2009-2019) revealed 72 patients with postoperative hemorrhage requiring reoperation. Each patient who developed postoperative hematoma was matched with four control patients that did not develop postoperative hematoma after thyroidectomy. The patients and controls were matched by the date of operation and surgeon performing thyroidectomy. RESULTS: The incidence of postoperative bleeding was 1.04%. On univariate analysis older age, male sex, higher BMI, higher ASA score, preoperative use of anticoagulant therapy, thyroidectomy for retrosternal goiter, larger thyroid specimens, larger dominant nodules, longer operative time, higher postoperative blood pressure and the use of postoperative subcutaneous heparin were identified as risk factors for postoperative bleeding. Sixty-nine patients (95.8%) bled within first 24 h after surgery. CONCLUSION: The rate of postoperative bleeding in our study is consistent with recent literature. Male sex, the use of preoperative anticoagulant therapy, thyroidectomy for retrosternal goiter and the use of postoperative subcutaneous heparin remained statistically significant on multivariate analysis (p < 0.001). When identified, these risk factors may be an obstacle to the outpatient thyroidectomy in our settings.


Asunto(s)
Bocio , Hematoma , Anticoagulantes/uso terapéutico , Estudios de Casos y Controles , Bocio/cirugía , Hematoma/epidemiología , Hematoma/etiología , Heparina , Humanos , Masculino , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Hemorragia Posoperatoria/complicaciones , Hemorragia Posoperatoria/etiología , Estudios Retrospectivos , Factores de Riesgo , Serbia/epidemiología , Tiroidectomía/efectos adversos
5.
J Toxicol Environ Health A ; 85(17): 699-714, 2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-35591784

RESUMEN

It is well-known that mushrooms of the genus Lactarius constitute a natural food resource providing health benefits as a nutritient. This genus contains 4 mushrooms identified as L. deliciosus, L. volemus, L. sanguifluus, L. semisanguifluus and L. piperatus which were collected in Serbia. The aim of this study aimed was to identify and characterize the content of phenolic compounds and examine the antioxidant potential of 5 wild edible mushrooms. L. sanguifluus contained the highest content of total phenol compounds (75.25 mg gallic acid equivalents (GAE) per g dry extract weight (GAE/g DE) and exhibited the greatest antioxidant activity through the ability to remove radicals as evidenced by ABTS assay (8.99 mg of trolox equivalents (TE) per g dry extract weight (mg TE/g DE); total reducing power (TRP) assay mg ascorbic acid equivalents per mg of dry extract weight (0.42 mg AAE/g DE) and CUPRAC (14.23 mg TE /g DE). L. deliciosus methanolic extract produced greatest scavenging of the DPPH radical (46%). The methanol mushroom extracts were screened for in vitro antimicrobial activity against a panel of pathogenic bacterial strains using the microdilution method. Of all the extracts tested, L. sanguifluus extract showed the best antibacterial properties. The cytokinesis block micronucleus assay results for the examined mushrooms demonstrated that extracts at a concentration of 3 µg/ml decreased the number of micronuclei (MN) in the range of 19-49% which is significant bearing in mind that radioprotectant amifostine reduced the frequency of MN by only 16.3%. Data thus demonstrate that the 5 wild edible mushrooms of genus Lactarius contain constituents that are beneficial not only as nutrients but also have the potential as antioxidants, antibacterial and antigenotoxic properties.


Asunto(s)
Agaricales , Antioxidantes , Agaricales/química , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Ácido Ascórbico , Fenoles/química , Extractos Vegetales/química
6.
Int J Mol Sci ; 21(16)2020 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-32796496

RESUMEN

Transepithelial transport of proteins is an important step in the immune response to food allergens. Mammalian meat allergy is characterized by an IgE response against the carbohydrate moiety galactosyl-α-1,3-galactose (α-Gal) present on mammalian glycoproteins and glycolipids, which causes severe allergic reactions several hours after red meat consumption. The delayed reaction may be related to the processing of α-Gal carrying proteins in the gastrointestinal tract. The aim of this study was to investigate how protein glycosylation by α-Gal affects the susceptibility to gastric digestion and transport through the Caco-2 cell monolayer. We found that α-Gal glycosylation altered protein susceptibility to gastric digestion, where large protein fragments bearing the α-Gal epitope remained for up to 2 h of digestion. Furthermore, α-Gal glycosylation of the protein hampered transcytosis of the protein through the Caco-2 monolayer. α-Gal epitope on the intact protein could be detected in the endosomal fraction obtained by differential centrifugation of Caco-2 cell lysates. Furthermore, the level of galectin-3 in Caco-2 cells was not affected by the presence of α-Gal glycosylated BSA (bovine serum albumin) (BSA-α-Gal). Taken together, our data add new knowledge and shed light on the digestion and transport of α-Gal glycosylated proteins.


Asunto(s)
Disacáridos/metabolismo , Proteínas/química , Transcitosis , Animales , Células CACO-2 , Carbohidratos/química , Bovinos , Endosomas/metabolismo , Galectina 3/metabolismo , Glicosilación , Humanos , Pepsina A/metabolismo , Transporte de Proteínas , Albúmina Sérica Bovina/metabolismo
7.
J Biol Inorg Chem ; 24(1): 61-70, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30456476

RESUMEN

Cys34 thiol group of human serum albumin (HSA) represents major plasma antioxidant. Its reactivity is influenced by multiple factors. The influence of fatty acids (FA; saturated, mono, and poly unsaturated acids from fish oil) binding to HSA, on copper(II) binding affinity and Cys34 thiol group accessibility/reactivity, in the presence of carbonylation agent (methylglyoxal, MG) was examined. HSA-copper(II) content, thiol group reactivity, and HSA carbonylation level were monitored spectrophotometrically. Changes in HSA were followed by fluorescence spectroscopy and native PAG electrophoresis. FA/HSA molar ratio was screened by GC. Together, binding of copper(II) ions and FA to HSA increase the reactivity of Cys34 thiol group (depending on the type of FA), with constant contribution of copper(II) ions of one-third. Carbonylation of FA-HSA-Cu(II) complexes caused a decrease in the Cys34 thiol group content, accompanied by a decrease in the content of HSA-bound copper. The carbonylation level of guanidine groups was not affected by FAs and copper(II) binding. Fluorescent emission spectra of FA-HSA-Cu(II)-MG complexes showed conformational changes in HSA molecule. Although binding of fatty acids and copper ions caused a significant increase in the thiol group reactivity, Cys34 thiol from FA-HSA-Cu(II) complexes reacted with MG in smaller extent than expected, probably as a consequence of conformational changes introduced by carbonylation. Increase in the percentage of reacted-free thiol groups with MG (due to FA and copper binding) may not seem to be very significant, but it is very important in complex biological systems, where catalytic metal is present.


Asunto(s)
Cobre/metabolismo , Cisteína/metabolismo , Ácidos Grasos/metabolismo , Albúmina Sérica Humana/metabolismo , Humanos , Unión Proteica , Carbonilación Proteica , Piruvaldehído/metabolismo
8.
Chem Biodivers ; 16(2): e1800492, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30458066

RESUMEN

The goal of this research was a comprehensive analysis of four wild edible mushroom species, Cantharellus cinereus, Clavariadelphus pistillaris, Clitocybe nebularis and Hygrocybe punicea, which have not been analyzed so far. Extracts of different polarities have been prepared and evaluated for their antioxidant activities by DPPH, ABTS, FRAP, TRP and CUPRAC methods. For all extracts, total phenolic content was determined. Based on the analysis, it was shown that solvent type had a significant effect on the antioxidant capacities of mushroom extracts, so water extracts showed the highest activity. Furthermore, the analysis includes determination of mineral composition, fatty acid profiles and antimicrobial activity. Unsaturated fatty acids, which are very important for human health, are dominant in the studied mushroom species. Linoleic and oleic acid consist of over 50 % of the total fatty acid composition. Seventeen biologically important and toxic elements have been analyzed by ICP-OES and ICP-MS and results showed that the element concentrations were species-dependent. Also, it has been found that analyzed mushrooms did not show any antimicrobial activity. Chemometric analysis was used to understand the connection between the extracts of different polarities.


Asunto(s)
Agaricales/química , Plantas Comestibles/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Ácidos Grasos/análisis , Minerales/análisis , Fenoles/análisis , Extractos Vegetales/química , Especificidad de la Especie
9.
Chem Biodivers ; 15(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29164790

RESUMEN

Eleven species of wild mushrooms which belong to Boletaceae and Russulaceae families were examined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) analysis for the presence of fatty acids. As far as we know, the fatty acid profiles of B. purpureus and B. rhodoxanthus were described for the first time. Twenty-six fatty acids were determined. Linoleic (19.5 - 72%), oleic (0.11 - 64%), palmitic (5.9 - 22%) and stearic acids (0.81 - 57%) were present in the highest contents. In all samples, unsaturated fatty acids dominate. Agglomerative hierarchical clustering was used to display the correlation between the fatty acids and their relationships with the mushroom species. Based on the fatty acids profile in the samples, the mushrooms can be divided into two families: Boletaceae and Russulaceae families, using cluster analysis.


Asunto(s)
Agaricales/química , Ácidos Grasos/análisis , Cromatografía de Gases , Espectrometría de Masas , Especificidad de la Especie
10.
Mikrochim Acta ; 185(12): 556, 2018 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-30465108

RESUMEN

The authors report on a novel sorbent (thermally treated natural zeolite; clinoptilolite) for use in dispersive micro-solid phase extraction (D-µ-SPE) of polycyclic aromatic hydrocarbons (PAHs) from water samples. The method was applied to the D-µ-SPE of 16 priority PAHs which then were quantified by gas chromatography with mass spectrometric detection (GC-MS). The method was validated in terms of specificity and selectivity, linearity and linear range, accuracy, precision, uncertainty, limits of detection and quantification. Figures of merit include (a) linear analytical ranges between 2.08 and 208 ppb, and (b) detection limits in the range from 0.01 to 0.92 ppb. The method was successfully applied to the determination of PAHs in river waters. Graphical abstract Schematic representation of dispersive micro-solid phase extraction (D-µ-SPE) of trace levels of PAHs in water samples by using thermally treated clinoptilolite as sorbent prior to gas chromatography-mass spectrometry analysis (GC-MS).

11.
Planta Med ; 82(7): 650-61, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26891001

RESUMEN

The objective of the present study to perform a comparative analysis of the chemical composition, antioxidant, and antimicrobial activities of the essential oils of plant species Hyssopus officinalis, Achillea grandifolia, Achillea crithmifolia, Tanacetum parthenium, Laserpitium latifolium, and Artemisia absinthium from Balkan Peninsula. The chemical analysis of essential oils was performed by using gas chromatography and gas chromatography-mass spectrometry. Monoterpenes were dominant among the recorded components, with camphor in T. parthenium, A. grandifolia, and A. crithmifolia (51.4, 45.4, and 25.4 %, respectively), 1,8-cineole in H. officinalis, A. grandifolia, and A. crithmifolia (49.1, 16.4, and 14.8 %, respectively), and sabinene in L. latifolium and A. absinthium (47.8 and 21.5 %). The antiradical and antioxidant activities were determined by using 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging methods. The essential oil of A. grandifolia has shown the highest antioxidant activity [IC50 of 33.575 ± 0.069 mg/mL for 2,2-diphenyl-1-picrylhydrazyl and 2.510 ± 0.036 mg vitamin C/g for the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assay]. The antimicrobial activity against 16 multiresistant pathogenic bacteria isolated from human source material was tested by the broth microdilution assay. The resulting minimum inhibitory concentration/minimum bactericidal concentration values ranged from 4.72 to 93.2 mg/mL. Therefore, the essential oils of the plant species included in this study may be considered to be prospective natural sources of antimicrobial substances, and may contribute as effective agents in the battle against bacterial multiresistance.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Aceites Volátiles/química , Aceites de Plantas/química , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Apiaceae/química , Asteraceae/química , Peninsula Balcánica , Humanos , Lamiaceae/química
12.
Chem Biodivers ; 13(1): 85-90, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26765355

RESUMEN

The chemical composition and in vitro antimicrobial activities of Dittrichia graveolens (L.) Greuter essential oil was studied. Moreover, using agglomerative hierarchical cluster (AHC) and principal component analyses (PCA), the interrelationships of the D. graveolens essential-oil profiles characterized so far (including the sample from this study) were investigated. To evaluate the chemical composition of the essential oil, GC-FID and GC/MS analyses were performed. Altogether, 54 compounds were identified, accounting for 92.9% of the total oil composition. The D. graveolens oil belongs to the monoterpenoid chemotype, with monoterpenoids comprising 87.4% of the totally identified compounds. The major components were borneol (43.6%) and bornyl acetate (38.3%). Multivariate analysis showed that the compounds borneol and bornyl acetate exerted the greatest influence on the spatial differences in the composition of the reported oils. The antimicrobial activity against five bacterial and one fungal strain was determined using a disk-diffusion assay. The studied essential oil was active only against Gram-positive bacteria.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Asteraceae/química , Bacterias Grampositivas/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Antibacterianos/aislamiento & purificación , Análisis por Conglomerados , Pruebas de Sensibilidad Microbiana , Análisis Multivariante , Aceites Volátiles/aislamiento & purificación
13.
J Sci Food Agric ; 95(6): 1217-35, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25043621

RESUMEN

BACKGROUND: In Serbia, delicatessen fruit alcoholic drinks are produced from autochthonous fruit-bearing species such as cornelian cherry, blackberry, elderberry, wild strawberry, European wild apple, European blueberry and blackthorn fruits. There are no chemical data on many of these and herein we analysed volatile minor constituents of these rare fruit distillates. Our second goal was to determine possible chemical markers of these distillates through a statistical/multivariate treatment of the herein obtained and previously reported data. RESULTS: Detailed chemical analyses revealed a complex volatile profile of all studied fruit distillates with 371 identified compounds. A number of constituents were recognised as marker compounds for a particular distillate. Moreover, 33 of them represent newly detected flavour constituents in alcoholic beverages or, in general, in foodstuffs. With the aid of multivariate analyses, these volatile profiles were successfully exploited to infer the origin of raw materials used in the production of these spirits. It was also shown that all fruit distillates possessed weak antimicrobial properties. CONCLUSION: It seems that the aroma of these highly esteemed wild-fruit spirits depends on the subtle balance of various minor volatile compounds, whereby some of them are specific to a certain type of fruit distillate and enable their mutual distinction.


Asunto(s)
Bebidas Alcohólicas/análisis , Aromatizantes/análisis , Frutas/química , Odorantes/análisis , Aceites Volátiles/análisis , Gusto , Compuestos Orgánicos Volátiles/análisis , Humanos , Extractos Vegetales/análisis , Rosaceae , Sambucus
14.
Anal Biochem ; 448: 50-7, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24316317

RESUMEN

During investigation of the changes of the Cys34 thiol group of human serum albumin (HSA) (isolated by affinity chromatography with Cibacron Blue (CB)) in diabetes, we found that the HSA-SH content was higher (11-33%) than the total serum thiol content. The influence of fatty acids (FA) binding to HSA on this discrepancy was investigated in vitro (using fluorescence and CD spectroscopy and GC) and with HSA samples from diabetic (n=20) and control groups (n=17). HSA-bound FA determine the selection of HSA molecules by CB and enhance reactivity and/or accessibility of the SH group. A high content of polyunsaturated FA (35.6%) leads to weaker binding of HSA molecules to CB. Rate constants of DTNB reaction with the SH group of HSA applied to a CB column, bound-HSA and unbound-HSA fractions, were 4.8×10(-3), 21.6×10(-3), and 11.2×10(-3) s(-1), respectively. The HSA-SH group of diabetics is more reactive compared with control individuals (rate constants 20.9×10(-3)±4.4×10(-3) vs 12.9×10(-3)±2.6×10(-3) s(-1), P<0.05). Recovery values of the SH group obtained after chromatography of HSA with bound stearic acid ranged from 110 to 140%, while those for defatted HSA were from 98.5 to 101.7%. Thus, HSA-bound FA leads to an increase of HSA-SH content and a contribution to total serum thiols, which make the determination of the thiol group unreliable.


Asunto(s)
Ácidos Grasos/química , Albúmina Sérica/química , Espectrometría de Fluorescencia , Compuestos de Sulfhidrilo/análisis , Cromatografía de Afinidad , Dicroismo Circular , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Humanos , Albúmina Sérica/aislamiento & purificación , Albúmina Sérica/metabolismo
15.
J Insect Physiol ; 155: 104649, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38754699

RESUMEN

Chemical substances are of utmost importance for the biotic interactions between animals and their predators/parasites; many of these semiochemicals are emitted for defence purposes. One of the most deterrent and toxic biogenic substances we know of is hydrogen cyanide, which can be stored by certain insects, millipedes, centipedes and arachnids in the form of stable and less volatile molecules. The aim of this study was to analyse the biology and chemistry of such a defence mechanism in a geophilomorph centipede (Chilopoda). The cyanogenic secretion of Clinopodes flavidus is discharged from the ventral glands, whose glandular units are located in the space between the cuticle and the trunk muscles and do not extend deep into the segment. In addition to hydrogen cyanide, the ventral secretion contains 2-methylpentanoic acid, benzaldehyde, benzoyl cyanide, 2-methyl branched C-9 carboxylic acid (tentatively identified as 2-methyloctanoic acid), methyl 2-phenylacetate, benzoic acid and mandelonitrile as well as four major proteins with a molecular weight of 150, 66.2, 59 and 55 kDa. The correlation between the presence of ventral glands and guarding with the female's ventral side facing away from the eggs and young indicates a functional link between these two traits. We hope that the specificity of the chemical composition of the ventral secretion could serve as a criterion for chemotaxonomy and that the analysis of more species will help to clarify the phylogenetic relationships within the Geophilomorpha.


Asunto(s)
Cianuro de Hidrógeno , Animales , Femenino , Cianuro de Hidrógeno/metabolismo , Quilópodos/metabolismo , Masculino , Artrópodos/fisiología , Feromonas/metabolismo , Feromonas/química
16.
Pharmaceuticals (Basel) ; 17(1)2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38256963

RESUMEN

BACKGROUND: Epilepsy is a chronic brain disease affecting millions of people worldwide, but little is known about the impact of anti-seizure medications on redox homeostasis. METHODS: This study aimed to compare the effects of the long-term use of oral anti-seizure medications in monotherapy (lamotrigine, carbamazepine, and valproate) on antioxidant enzymes: superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, haemoglobin, and methaemoglobin content in erythrocytes, and concentrations of total proteins and thiols, nitrites, lipid peroxides and total glutathione in the plasma of epilepsy patients and drug-naïve patients. RESULTS: The results showed that lamotrigine therapy led to lower superoxide dismutase activity (p < 0.005) and lower concentrations of total thiols (p < 0.01) and lipid peroxides (p < 0.01) compared to controls. On the other hand, therapy with carbamazepine increased nitrite levels (p < 0.01) but reduced superoxide dismutase activity (p < 0.005). In the valproate group, only a decrease in catalase activity was observed (p < 0.005). Canonical discriminant analysis showed that the composition of antioxidant enzymes in erythrocytes was different for both the lamotrigine and carbamazepine groups, while the controls were separated from all others. CONCLUSIONS: Monotherapy with anti-seizure medications discretely alters redox homeostasis, followed by distinct relationships between antioxidant components.

17.
Anal Biochem ; 433(2): 162-7, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23103397

RESUMEN

Carbonylation of the protein amino, guanidine, and thiol groups with α-oxoaldehydes (which are produced in higher quantities in diabetes, uremia, oxidative stress, aging, and inflammation) is one of the important causes of vascular complications. For monitoring of the human serum albumin (HSA) carbonylation level, a spectrophotometric method based on the formation of colored adduct between guanidine group and thymol-sodium hypobromite reagent in the alkaline medium was investigated. Beer's law is obeyed in the concentration range of Arg and protein guanidine groups from 1 to 40 mM. Precision of the method (relative standard deviation) was in the range of 0.9 to 2%. Accuracy was examined by the standard addition method (recovery ~100%). The method was applied for monitoring of the carbonylation level of HSA with methylglyoxal in vitro and of HSA isolated (using affinity chromatography) from sera of 21 patients with type 2 diabetes and 12 healthy persons. The content of guanidine groups in HSA isolated from diabetics (19.64 ± 1.07 mM/mM albumin) was significantly lower (P < 0.001) in comparison with a control group (21.87 ± 1.02 mM/mM albumin). The method is simple and fast, has good accuracy and precision, and is suitable for clinical practice as well for in vitro protein carbonylation experiments.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Carbonilación Proteica , Albúmina Sérica/metabolismo , Femenino , Guanidina/sangre , Humanos , Masculino , Espectrofotometría Ultravioleta/métodos
18.
Anal Biochem ; 439(1): 17-22, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23583909

RESUMEN

The thiol (Cys34) content of human serum albumin (HSA-SH) decreases during oxidative and carbonyl stress and, therefore, could represent a useful parameter in clinical practice. Nevertheless, the reliability of HSA-thiol determination with Ellman's method depends on the purity of isolated HSA. Determination of total serum thiols (mmol/L) and HSA-SH content (mmol -SH/mmol HSA) after HSA isolation from diabetic patient and control sera by a two-step precipitation with ammonium sulfate (AS), as well as HSA-SH contribution (%) to total serum thiols, was assessed. Purity and yield of isolated HSA were monitored spectrophotometrically and by native polyacrylamide gel electrophoresis. Precipitation of HSA from serum via a two-step method with AS produced HSA with 91.9±3.6% purity and 69.7±4.4% yield, allowing for precise (relative standard deviation of 3.2%) and reliable (comparing with total serum thiols) measurement of HSA-SH content with DTNB [5,5'-dithiobis-(2-nitrobenzoic acid)]. The content of the HSA-SH group in patients with type 2 diabetes was significantly (P<0.05) lower compared with that of the healthy cohort (0.483±0.067 vs. 0.561±0.054 mmol -SH/mmol HSA). Because the proposed method of HSA isolation is simple, time-efficient, and technically less demanding, and it also enables reliable determination of HSA-SH content, it is suitable for clinical practice.


Asunto(s)
Albúmina Sérica/química , Compuestos de Sulfhidrilo/análisis , Sulfato de Amonio/química , Precipitación Química , Diabetes Mellitus Tipo 2/sangre , Humanos , Reproducibilidad de los Resultados , Albúmina Sérica/aislamiento & purificación
19.
Arq Bras Oftalmol ; 86(5): e20230059, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35544929

RESUMEN

We report a case of acute corneal hydrops followed by corneal perforation five years after corneal cross-linking for keratoconus. A healthy 24-year-old female patient underwent Dresden protocol cross-linking in her left eye due to advanced keratoconus. After five years of a stable cornea, she returned with epiphora, blurred vision, and a soft left eye. Acute hydrops and corneal perforation were diagnosed. There was no history of pregnancy, atopy, eye rubbing, trauma, or contact lens use. Local antibiotic and eye patching were applied. Three months after the resolution of the acute episode, she retained useful visual acuity with no need for further surgery. Although cross-linking efficiently halts keratoconus, progression can occur, leading to corneal hydrops and perforation, even in the absence of any risk factors.


Asunto(s)
Edema Corneal , Perforación Corneal , Queratocono , Humanos , Femenino , Adulto Joven , Adulto , Queratocono/complicaciones , Queratocono/tratamiento farmacológico , Queratocono/cirugía , Perforación Corneal/etiología , Reticulación Corneal , Edema/complicaciones , Edema Corneal/etiología , Topografía de la Córnea
20.
Materials (Basel) ; 16(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37445132

RESUMEN

The spillage of oil causes severe and long-lasting impacts on both the environment and human life. It is crucial to carefully reconsider the methods and techniques currently employed to recover spilled oil in order to prevent any possible secondary pollution and save time. Therefore, the techniques used to recover spilled oil should be readily available, highly responsive, cost-effective, environmentally safe, and, last but not least, they should have a high sorption capacity. The use of sorbents obtained from natural materials is considered a suitable approach for dealing with oil spills because of their exceptional physical characteristics that support sustainable environmental protection strategies. This article presents a novel sorbent material, which is a composite siloxane foam filled with bentonite clay, aimed at enhancing the hydrophobic and oleophilic behavior of the material. The thermal treatment of bentonite optimizes its sorption capacity by eliminating water, and increasing the surface area, and, consequently, its interaction with oils. In particular, the maximum sorption capacity is observed in kerosene and naphtha for the bentonite clay thermally treated at 600 °C, showing an uptake at saturation of 496.8% and 520.1%, respectively. Additionally, the reusability of the composite foam is evaluated by squeezing it after reaching its saturation point to determine its sorption capacity and reusability.

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