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1.
Plants (Basel) ; 13(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38592882

RESUMO

The systemic electrical signal propagation in plants (i.e., from leaf to leaf) is dependent on GLUTAMATE RECEPTOR-LIKE proteins (GLRs). The GLR receptors are the homologous proteins to the animal ionotropic glutamate receptors (iGluRs) which are ligand-gated non-selective cation channels that mediate neurotransmission in the animal's nervous system. In this study, we investigated the effect of the general anaesthetic ketamine, a well-known non-competitive channel blocker of human iGluRs, on systemic electrical signal propagation in Arabidopsis thaliana. We monitored the electrical signal propagation, intracellular calcium level [Ca2+]cyt and expression of jasmonate (JA)-responsive genes in response to heat wounding. Although ketamine affected the shape and the parameters of the electrical signals (amplitude and half-time, t1/2) mainly in systemic leaves, it was not able to block a systemic response. Increased [Ca2+]cyt and the expression of jasmonate-responsive genes were detected in local as well as in systemic leaves in response to heat wounding in ketamine-treated plants. This is in contrast with the effect of the volatile general anaesthetic diethyl ether which completely blocked the systemic response. This low potency of ketamine in plants is probably caused by the fact that the critical amino acid residues needed for ketamine binding in human iGluRs are not conserved in plants' GLRs.

2.
Viruses ; 15(8)2023 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-37632037

RESUMO

BACKGROUND: It is assumed that the prevalence of hepatitis D in HBsAg-positive individuals reaches 4.5-13% in the world and on average about 3% in Europe. Data from several European countries, including Slovakia, are missing or are from an older period. METHODS: We analyzed all available data on hepatitis D from Slovakia, including reports from the Slovak Public Health Authority and the results of one prospective study, and three smaller surveys. The determination of anti-HDV IgG and IgM antibodies and/or HDV RNA was used to detect hepatitis D. RESULTS: In the years 2005-2022, no confirmed case of acute or chronic HDV infection was reported in Slovakia. The presented survey includes a total of 343 patients, of which 126 were asymptomatic HBsAg carriers, 33 acute hepatitis B, and 184 chronic hepatitis B cases. In a recent prospective study of 206 HBsAg-positive patients who were completely serologically and virologically examined for hepatitis B and D, only 1 anti-HDV IgG-positive and no anti-HDV IgM or HDV RNA-positive cases were detected. In other smaller surveys, two anti-HDV IgG-positive patients were found without the possibility of HDV RNA confirmation. In total, only 3 of 329 HBsAg-positive patients (0.91%) tested positive for anti-HDV IgG antibodies, and none of 220 tested positive for HDV RNA. CONCLUSION: The available data show that Slovakia is one of the countries with a very low prevalence of HDV infection, reaching less than 1% in HBsAg-positive patients. Routine testing for hepatitis D is lacking in Slovakia, and therefore it is necessary to implement testing of all HBsAg-positive individuals according to international recommendations.


Assuntos
Hepatite B , Hepatite D , Humanos , Eslováquia/epidemiologia , Antígenos de Superfície da Hepatite B , Estudos Prospectivos , Hepatite D/diagnóstico , Hepatite D/epidemiologia , Imunoglobulina M , Infecção Persistente , Imunoglobulina G
3.
Curr Oncol ; 30(3): 3557-3570, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36975484

RESUMO

Hepatocellular carcinoma (HCC) has multiple molecular classes that are associated with distinct etiologies and, besides particular molecular characteristics, that also differ in clinical aspects. We aim to characterize the clinical aspects of alcoholic liver disease-related HCC by a retrospective observational study that included all consequent patients diagnosed with MRI or histologically verified HCC in participating centers from 2010 to 2016. A total of 429 patients were included in the analysis, of which 412 patients (96%) had cirrhosis at the time of diagnosis. The most common etiologies were alcoholic liver disease (ALD) (48.3%), chronic hepatitis C (14.9%), NAFLD (12.6%), and chronic hepatitis B (10%). Patients with ALD-related HCC were more commonly males, more commonly had cirrhosis that was in more advanced stages, and had poorer performance status. Despite these results, no differences were observed in the overall (median 8.1 vs. 8.5 months) and progression-free survival (median 4.9 vs. 5.7 months). ALD-HCC patients within BCLC stage 0-A less frequently received potentially curative treatment as compared to the control HCC patients (62.2% vs. 87.5%, p = 0.017); and in patients with ALD-HCC liver function (MELD score) seemed to have a stronger influence on the prognosis compared to the control group HCC. Systemic inflammatory indexes were strongly associated with survival in the whole cohort. In conclusion, alcoholic liver disease is the most common cause of hepatocellular carcinoma in Slovakia, accounting for almost 50% of cases; and patients with ALD-related HCC more commonly had cirrhosis that was in more advanced stages and had poorer performance status, although no difference in survival between ALD-related and other etiology-related HCC was observed.


Assuntos
Carcinoma Hepatocelular , Hepatopatias Alcoólicas , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Masculino , Humanos , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/diagnóstico , Eslováquia/epidemiologia , Hepatopatias Alcoólicas/complicações , Hepatopatias Alcoólicas/patologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/patologia
4.
Front Plant Sci ; 13: 995001, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36172556

RESUMO

General volatile anesthetic diethyl ether blocks sensation and responsive behavior not only in animals but also in plants. Here, using a combination of RNA-seq and proteomic LC-MS/MS analyses, we investigated the effect of anesthetic diethyl ether on gene expression and downstream consequences in plant Arabidopsis thaliana. Differential expression analyses revealed reprogramming of gene expression under anesthesia: 6,168 genes were upregulated, 6,310 genes were downregulated, while 9,914 genes were not affected in comparison with control plants. On the protein level, out of 5,150 proteins identified, 393 were significantly upregulated and 227 were significantly downregulated. Among the highest significantly downregulated processes in etherized plants were chlorophyll/tetrapyrrole biosynthesis and photosynthesis. However, measurements of chlorophyll a fluorescence did not show inhibition of electron transport through photosystem II. The most significantly upregulated process was the response to heat stress (mainly heat shock proteins, HSPs). Using transgenic A. thaliana expressing APOAEQUORIN, we showed transient increase of cytoplasmic calcium level [Ca2+]cyt in response to diethyl ether application. In addition, cell membrane permeability for ions also increased under anesthesia. The plants pre-treated with diethyl ether, and thus with induced HSPs, had increased tolerance of photosystem II to subsequent heat stress through the process known as cross-tolerance or priming. All these data indicate that diethyl ether anesthesia may partially mimic heat stress in plants through the effect on plasma membrane.

5.
Photosynth Res ; 154(1): 21-40, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35980499

RESUMO

The acclimation of higher plants to different light intensities is associated with a reorganization of the photosynthetic apparatus. These modifications, namely, changes in the amount of peripheral antenna (LHCII) of photosystem (PS) II and changes in PSII/PSI stoichiometry, typically lead to an altered chlorophyll (Chl) a/b ratio. However, our previous studies show that in spruce, this ratio is not affected by changes in growth light intensity. The evolutionary loss of PSII antenna proteins LHCB3 and LHCB6 in the Pinaceae family is another indication that the light acclimation strategy in spruce could be different. Here we show that, unlike Arabidopsis, spruce does not modify its PSII/PSI ratio and PSII antenna size to maximize its photosynthetic performance during light acclimation. Its large PSII antenna consists of many weakly bound LHCIIs, which form effective quenching centers, even at relatively low light. This, together with sensitive photosynthetic control on the level of cytochrome b6f complex (protecting PSI), is the crucial photoprotective mechanism in spruce. High-light acclimation of spruce involves the disruption of PSII macro-organization, reduction of the amount of both PSII and PSI core complexes, synthesis of stress proteins that bind released Chls, and formation of "locked-in" quenching centers from uncoupled LHCIIs. Such response has been previously observed in the evergreen angiosperm Monstera deliciosa exposed to high light. We suggest that, in contrast to annuals, shade-tolerant evergreen land plants have their own strategy to cope with light intensity changes and the hallmark of this strategy is a stable Chl a/b ratio.


Assuntos
Arabidopsis , Picea , Aclimatação , Arabidopsis/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Complexo Citocromos b6f/metabolismo , Citocromos b/metabolismo , Proteínas de Choque Térmico/metabolismo , Luz , Complexos de Proteínas Captadores de Luz/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Picea/metabolismo
6.
J Clin Med ; 11(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887947

RESUMO

Background and Aims: Hepatocellular cancer (HCC) often occurs in geriatric patients. The aim of our study was to compare overall survival and progression-free survival between geriatric patients (>75 years) and patients younger than 75 years and to identify predictive factors of survival in geriatric patients with HCC. Material and Methods: We performed a retrospective analysis of patients with HCC diagnosed in Slovakia between 2010−2016. Cases (HCC patients ≥75 years) were matched to controls (HCC patients <74 years) based on the propensity score (gender, BCLC stage and the first-line treatment). Results: We included 148 patients (84 men, 57%) with HCC. There were no differences between cases and controls in the baseline characteristics. The overall survival in geriatric patients with HCC was comparable to younger controls (p = 0.42). The one-, two-, and three-year overall survival was 42% and 31%, 19% and 12%, and 12% and 9% in geriatric patients and controls, respectively (p = 0.2, 0.4, 0.8). Similarly, there was no difference in the one- and two-year progression-free survival: 28% and 18% vs. 10% and 7% in geriatric HCC patients and controls, respectively (p = 0.2, 1, -). There was no case−control difference between geriatric HCC patients and younger HCC controls in the overall survival in the subpopulation of patients with no known comorbidities (p = 0.5), one and two comorbidities (p = 0.49), and three or more comorbidities (p = 0.39). Log (CRP), log (NLR), log (PLR), and log (SII) were all associated with the three-year survival in geriatric HCC patients in simple logistic regression analyses. However, this time, only log (NLR) remained associated even after controlling for the age and BCLC confounding (OR 5.32, 95% CI 1.43−28.85). Conclusions. We found no differences in overall survival and progression-free survival between older and younger HCC patients. Parameters of subclinical inflammation predict prognosis in geriatric patients with HCC. A limitation of the study is small number of the treated patients; therefore, further investigation is warranted.

7.
Bratisl Lek Listy ; 123(7): 496-504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35907056

RESUMO

OBJECTIVES: Non-communicable diseases are estimated to account for 90 % of total deaths and 19 % of premature deaths in Slovakia. Major preventable risk factors of premature mortality are overweight, obesity and alcohol consumption. BACKGROUND: Screening of risk factors related to alcoholic and nonalcoholic fatty liver diseases (AFLD and NAFLD, respectively) in Slovak outpatients with liver disease. METHODS: A total group of 923 patients, aged 19-91 years were included in the study. Self-administered anonymous questionnaires (Q) were filled in by them. Twelve questions were included relating to age, gender, education, BMI, intake of vegetable, fruit, fish, alcohol, and coffee, as well as to smoking and physical exercise. RESULTS: Overweight/obesity was detected in 59 % of patients, insufficient fiber intake in 87 % of patients, insufficient fish intake in 85 % of patients, and insufficient physical exercise in 68 % of patients. BMI over 25 together with the risk of alcohol consumption was present in 68 % of patients. Smoking was present in 19 % of patients and insufficient coffee intake (from its hepatoprotective point of view) was in 35 % of patients. A total proportion of 75 % of patients were at risk for NAFLD. The risk of alcohol consumption was present in 64 % of patients. CONCLUSIONS: An anonymous questionnaire is a useful screening tool for searching for the risks of NAFLD and AFLD in general practice. Recommendation of a screening schedule for general practitioners is implemented (Tab. 2, Fig. 4, Ref. 36).


Assuntos
Hepatopatia Gordurosa não Alcoólica , Café/efeitos adversos , Humanos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade , Sobrepeso , Fatores de Risco , Inquéritos e Questionários
8.
Plant Physiol Biochem ; 169: 311-321, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34826706

RESUMO

General volatile anaesthetics (GVA) inhibit electrical signal propagation in animal neurons. Although plants do not have neurons, they generate and propagate electrical signals systemically from a local damaged leaf to neighbouring leaves. This systemic electrical signal propagation is mediated by ligand-gated glutamate receptor-like (GLR) channels. Here, we investigated the effect of GVA diethyl ether on the systemic electrical and further downstream responses in Arabidopsis thaliana. We monitored electrical signals, cytoplasmic Ca2+ level ([Ca2+]cyt), ultra-weak photon emission, amino acid contents, phytohormone response as well as gene expression in response to heat wounding during diethyl ether anaesthesia. We found complete suppression of electrical and [Ca2+]cyt signal propagation from damaged leaf to neighbouring systemic leaves upon diethyl ether treatment. Concomitantly, jasmonates (JAs) did not accumulate and expression of JA-responsive genes (AOS, OPR3, JAZ10) was not detected in systemic leaves. However local damaged leaves still showed increased [Ca2+]cyt and accumulated high level of JAs and JA-inducible transcripts. An exogenously added GLR ligand, L-glutamate, was not able to trigger Ca2+ wave in etherized plants indicating that GLRs are targeted by diethyl ether, but not specifically. The fact that GVA inhibit electrical signal propagation not only in animals but also in plants is intriguing. However, the cellular response is completely blocked only in systemic leaves; the local damaged leaf still senses damaging stimuli.


Assuntos
Anestésicos , Proteínas de Arabidopsis , Arabidopsis , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Ciclopentanos/farmacologia , Éter , Regulação da Expressão Gênica de Plantas , Oxilipinas/farmacologia , Folhas de Planta/metabolismo
9.
J Clin Med ; 10(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34300352

RESUMO

OBJECTIVE: To compare NAFLD-related HCC and other etiology-related HCC and to describe predictive factors for survival in patients with NAFLD-related HCC independent of the BCLC staging system. METHODS: We performed a multicenter longitudinal retrospective observational study of patients diagnosed with HCC during the period from 2010 through 2016. RESULTS: 12.59% of patients had NAFLD-related HCC, and 21.91% had either NAFLD or cryptogenic etiology. NAFLD-related HCC patients were younger (p = 0.0007), with a higher proportion of women (p < 0.001) compared to other etiology-related HCC patients. The NAFLD group had a significantly lower proportion of patients with liver cirrhosis at the time of HCC diagnosis (p < 0.0001), and they were more frequently diagnosed with both diabetes and metabolic syndrome when compared to other etiology-related HCC (p < 0.0001). We did not find any difference in the overall survival or in the progression-free survival between NAFLD-related and other etiology-related HCC patients staged as BCLC B and BCLC C. NAFLD-related HCC patients with three or more liver lesions had a shorter overall survival when compared to patients with one or two liver lesions (p = 0.0097), while patients with baseline CRP values of ≥5 mg/L or with PLR ≥ 150 had worse overall survival (p = 0.012 and p = 0.0028, respectively). ALBI Grade 3 predicted worse overall survival compared to ALBI Grade 1 or 2 (p = 0.00021). In NAFLD-related HCC patients, PLR and ALBI remained significant predictors of overall survival even after adjusting for BCLC. CONCLUSION: NAFLD-related HCC patients have a similar prognosis when compared to other etiology-related HCC. In NAFLD-related HCC patients, ALBI and PLR are significant predictors of the overall survival independent of the BCLC staging system.

10.
Physiol Plant ; 171(2): 246-259, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33215689

RESUMO

Lipid peroxidation is a primary event associated with oxidative stress in plants. This phenomenon secondarily generates bioactive and/or toxic compounds such as reactive carbonyl species (RCS), phytoprostanes, and phytofurans, as confirmed here in Arabidopsis plants exposed to photo-oxidative stress conditions. We analyzed the effects of exogenous applications of secondary lipid oxidation products on Arabidopsis plants by luminescence techniques. Oxidative damage to attached leaves was measured by autoluminescence imaging, using a highly sensitive CCD camera, and the activity of the detoxification pathway, dependent on the transcription regulator SCARECROW-LIKE 14 (SCL14), was monitored with a bioluminescent line expressing the firefly LUCIFERASE (LUC) gene under the control of the ALKENAL REDUCTASE (AER) gene promoter. We identified 4-hydroxynonenal (HNE), and to a lesser extent 4-hydroxyhexenal (HHE), as highly reactive compounds that are harmful to leaves and can trigger AER gene expression, contrary to other RCS (pentenal, hexenal) and to isoprostanoids. Although the levels of HNE and other RCS were enhanced in the SCL14-deficient mutant (scl14), exogenously applied HNE was similarly damaging to this mutant, its wild-type parent and a SCL14-overexpressing transgenic line (OE:SCL14). However, strongly boosting the SCL14 detoxification pathway and AER expression by a pre-treatment of OE:SCL14 with the signaling apocarotenoid ß-cyclocitral canceled the damaging effects of HNE. Conversely, in the scl14 mutant, the effects of ß-cyclocitral and HNE were additive, leading to enhanced leaf damage. These results indicate that the cellular detoxification pathway induced by the low-toxicity ß-cyclocitral targets highly toxic compounds produced during lipid peroxidation, reminiscent of a safener-type mode of action.


Assuntos
Peroxidação de Lipídeos , Luminescência , Aldeídos , Diterpenos , Estresse Oxidativo , Folhas de Planta , Espécies Reativas de Oxigênio
11.
Front Physiol ; 11: 552569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178031

RESUMO

The U937 cell culture is a pro-monocytic, human histiocytic lymphoma cell line. These monocytes can differentiate into either macrophages or dendritic cells (antigen-presenting cells) depending on the initiators. The U937 cells activated in the presence of phorbol 12-myristate 13-acetate (PMA) change their morphology into macrophage-like cells creating pseudopodia and adhering generously. Macrophages are known to produce reactive oxygen species (ROS) mostly during phagocytosis of foreign particles, an important non-specific immune response. Recently, we have focused on the role of hydroxyl radical (HO∙) and provide evidence on its importance for differentiation in U937 cells. Based on electron paramagnetic resonance (EPR) spectroscopy combined with confocal laser scanning microscopy (CLSM), formation of HO∙ was confirmed within the cells undergoing differentiation and/or apoptosis during the PMA treatment. This study aims to increase our knowledge of ROS metabolism in model cell lines used in human research.

12.
Int J Mol Sci ; 21(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143091

RESUMO

Leaf senescence, accompanied by chlorophyll breakdown, chloroplast degradation and inhibition of photosynthesis, can be suppressed by an exogenous application of cytokinins. Two aromatic cytokinin arabinosides (6-benzylamino-9-ß-d-arabinofuranosylpurines; BAPAs), 3-hydroxy- (3OHBAPA) and 3-methoxy- (3MeOBAPA) derivatives, have recently been found to possess high anti-senescence activity. Interestingly, their effect on the maintenance of chlorophyll content and maximal quantum yield of photosystem II (PSII) in detached dark-adapted leaves differed quantitatively in wheat (Triticum aestivum L. cv. Aranka) and Arabidopsis (Arabidopsisthaliana L. (Col-0)). In this work, we have found that the anti-senescence effects of 3OHBAPA and 3MeOBAPA in wheat and Arabidopsis also differ in other parameters, including the maintenance of carotenoid content and chloroplasts, rate of reduction of primary electron acceptor of PSII (QA) as well as electron transport behind QA, and partitioning of absorbed light energy in light-adapted leaves. In wheat, 3OHBAPA had a higher protective effect than 3MeOBAPA, whereas in Arabidopsis, 3MeOBAPA was the more efficient derivative. We have found that the different anti-senescent activity of 3OHBAPA and 3MeOBAPA was coupled to different ethylene production in the treated leaves: the lower the ethylene production, the higher the anti-senescence activity. 3OHBAPA and 3MeOBAPA also efficiently protected the senescing leaves of wheat and Arabidopsis against oxidative damage induced by both H2O2 and high-light treatment, which could also be connected with the low level of ethylene production.


Assuntos
Arabidopsis/metabolismo , Senescência Celular , Citocininas/farmacologia , Etilenos/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/metabolismo , Triticum/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Fotossíntese , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento
13.
Int J Public Health ; 65(9): 1723-1735, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33040165

RESUMO

OBJECTIVES: The MOSAIC study gathered data on chronic hepatitis C virus (HCV) infection and its treatment in various countries worldwide. Here we summarise patient and HCV characteristics in the Czech Republic and Slovakia. METHODS: MOSAIC was an observational study that included patients with chronic HCV infection untreated at the time of enrolment. Study collected and descriptively analysed patient demographics, disease stage and viral characteristics. Data were collected between February 2014 to October 2014. RESULTS: Among 220 patients enrolled, 51.4% were treatment-naïve. The most prevalent HCV genotype was G1 (78.4%), followed by G3 (19.7%). Higher prevalence of G1 was found in treatment-experienced patients (94.3%) compared to treatment-naïve (63.4%). Most participants (67.7%) presented viral RNA load of ≥ 800,000 IU/mL. Liver cirrhosis was reported in 24.5% of patients. Higher HCV RNA load and duration of HCV infection correlated with the degree of liver fibrosis. Anti-HCV interferon-based treatments were initiated in 88.2% of participants. CONCLUSIONS: The study confirmed significant changes in the HCV genotypes partition with G3 genotype rapidly increasing in both countries, with possible impact on the WHO eradication initiative and treatment selection.


Assuntos
Hepatite C Crônica/epidemiologia , Adulto , Idoso , República Tcheca/epidemiologia , Feminino , Genótipo , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Cirrose Hepática/virologia , Masculino , Pessoa de Meia-Idade , Prevalência , RNA Viral , Índice de Gravidade de Doença , Eslováquia/epidemiologia , Fatores Socioeconômicos , Carga Viral , Adulto Jovem
14.
Biomolecules ; 9(7)2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284470

RESUMO

It is well known that biological systems, such as microorganisms, plants, and animals, including human beings, form spontaneous electronically excited species through oxidative metabolic processes. Though the mechanism responsible for the formation of electronically excited species is still not clearly understood, several lines of evidence suggest that reactive oxygen species (ROS) are involved in the formation of electronically excited species. This review attempts to describe the role of ROS in the formation of electronically excited species during oxidative metabolic processes. Briefly, the oxidation of biomolecules, such as lipids, proteins, and nucleic acids by ROS initiates a cascade of reactions that leads to the formation of triplet excited carbonyls formed by the decomposition of cyclic (1,2-dioxetane) and linear (tetroxide) high-energy intermediates. When chromophores are in proximity to triplet excited carbonyls, the triplet-singlet and triplet-triplet energy transfers from triplet excited carbonyls to chromophores result in the formation of singlet and triplet excited chromophores, respectively. Alternatively, when molecular oxygen is present, the triplet-singlet energy transfer from triplet excited carbonyls to molecular oxygen initiates the formation of singlet oxygen. Understanding the mechanism of the formation of electronically excited species allows us to use electronically excited species as a marker for oxidative metabolic processes in cells.


Assuntos
Espécies Reativas de Oxigênio/metabolismo , Animais , Transferência de Energia , Humanos , Oxirredução , Oxigênio/metabolismo
15.
Front Plant Sci ; 10: 1660, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31998345

RESUMO

Mechanical injury or wounding in plants can be attributed to abiotic or/and biotic causes. Subsequent defense responses are either local, i.e. within or in the close vicinity of affected tissue, or systemic, i.e. at distant plant organs. Stress stimuli activate a plethora of early and late reactions, from electric signals induced within seconds upon injury, oxidative burst within minutes, and slightly slower changes in hormone levels or expression of defense-related genes, to later cell wall reinforcement by polysaccharides deposition, or accumulation of proteinase inhibitors and hydrolytic enzymes. In the current study, we focused on the production of reactive oxygen species (ROS) in wounded Arabidopsis leaves. Based on fluorescence imaging, we provide experimental evidence that ROS [superoxide anion radical (O2 •-) and singlet oxygen (1O2)] are produced following wounding. As a consequence, oxidation of biomolecules is induced, predominantly of polyunsaturated fatty acid, which leads to the formation of reactive intermediate products and electronically excited species.

16.
Can J Gastroenterol Hepatol ; 2018: 6095097, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30402450

RESUMO

Background and Aims: Chronic hepatitis C is a systemic disease and type 2 diabetes mellitus (T2DM) belongs to more common extrahepatic. The aim of this study was to (i) explore the prevalence of impaired fasting glucose (IFG) and T2DM in patients with chronic hepatitis C, (ii) explore the effect of direct acting antivirals (DAA) treatment on the glycemia, and (iii) explore the factors that modulate the effect of DAA treatment on glycemia in patients with chronic hepatitis C. Methods: We performed a longitudinal retrospective observational study focused on the patients undergoing DAA treatment of chronic hepatitis C. Data about glycemia, history of diabetes, hepatitis C virus, treatment, and liver status, including elastography, were obtained at baseline (before treatment start), at the end of treatment and 12 weeks after the end of treatment. Patients were treated with various regimens of direct acting antivirals. Results: We included 370 patients; 45.9% had F4 fibrosis. At baseline, the prevalence of T2DM increased with the degree of fibrosis (F0-F2 14.4%, F3 21.3%, and F4 31.8%, p=0.004). Fasting glycemia also increased with the degree of fibrosis (F0-F2 5.75±0.18 F3 5.84±0.17, and F4 6.69±0.2 mmol/L, p=0.001). We saw significant decrease of glycemia after treatment in all patients, but patients without T2DM or IFG from 6.21±0.12 to 6.08±0.15 mmol/L (p=0.002). The decrease was also visible in treatment experienced patients and patients with Child-Pugh A cirrhosis. Conclusion: We confirmed that the prevalence of either T2DM or IFG increases in chronic hepatitis C patients with the degree of fibrosis. The predictive factors for T2DM were, besides F4, fibrosis also higher age and BMI. Significant decrease of fasting glycemia after the DAA treatment was observed in the whole cohort and in subgroups of patients with T2DM, IFG, cirrhotic, and treatment experienced patients.


Assuntos
Antivirais/uso terapêutico , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/epidemiologia , Intolerância à Glucose/epidemiologia , Hepatite C Crônica/sangue , Fatores Etários , Glicemia/efeitos dos fármacos , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etiologia , Jejum/sangue , Feminino , Intolerância à Glucose/sangue , Intolerância à Glucose/etiologia , Hepacivirus , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Humanos , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento
17.
Vnitr Lek ; 64(7-8): 735-741, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30441981

RESUMO

Obesity reaches the dimensions of the global epidemic. It directly contributes to an increase in the prevalence of systemic diseases associated with obesity. Obesity and overweight globally cause 3.5 million deaths annually [1]. Non-alcoholic fatty liver disease has become the most common chronic liver disease in developed countries and is considered to be a liver manifestation of metabolic syndrome. The extent and burden of the disease are increasing and reaching epidemic proportions because of its close association with the epidemic of obesity and diabetes mellitus type [2]. It affects 30 % of the adult population [2]. There is an alarming increase in prevalence among children and adolescents. However, in the group of patients with high cardiometabolic risk, we can see a significantly higher prevalence of NAFLD. Prevalence in obese patients is 75 -92 %, in diabetic patients prevalence is between 60 -70 % [3]. A significant proportion of patients with NAFLD will suffer from a progressive form of the disease - non-alcoholic steatohepatitis (NASH), which is associated with the development of advanced liver fibrosis, cirrhosis, and its complications. The growing prevalence of NASH in the near future will bring the advanced cohort of our patients to the stage of an advanced liver disease. If the adverse epidemiological trend is not reversed, in the next decade the most common cause of liver transplantation will be NASH. A steadily rising trend can be seen in an increase in the number of cases of hepatocellular carcinoma causally related to NASH [4]. Treatment based on the influence of key pathogenetic mechanisms could alter the individual's future as well as the global burden arising with NASH. New molecules with anti-inflammatory and antifibrotic effects will play a key role in the future. Key words: cirrhosis - insulin resistance - metabolic syndrome - NASH.


Assuntos
Cirrose Hepática , Síndrome Metabólica , Hepatopatia Gordurosa não Alcoólica , Adolescente , Adulto , Criança , Humanos , Cirrose Hepática/complicações , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade
18.
Plant J ; 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29901834

RESUMO

Prenylquinols (tocochromanols and plastoquinols) serve as efficient physical and chemical quenchers of singlet oxygen (1 O2 ) formed during high light stress in higher plants. Although quenching of 1 O2 by prenylquinols has been previously studied, direct evidence for chemical quenching of 1 O2 by plastoquinols and their oxidation products is limited in vivo. In the present study, the role of plastoquinol-9 (PQH2 -9) in chemical quenching of 1 O2 was studied in Arabidopsis thaliana lines overexpressing the SOLANESYL DIPHOSPHATE SYNTHASE 1 gene (SPS1oex) involved in PQH2 -9 and plastochromanol-8 biosynthesis. In this work, direct evidence for chemical quenching of 1 O2 by plastoquinols and their oxidation products is presented, which is obtained by microscopic techniques in vivo. Chemical quenching of 1 O2 was associated with consumption of PQH2 -9 and formation of its various oxidized forms. Oxidation of PQH2 -9 by 1 O2 leads to plastoquinone-9 (PQ-9), which is subsequently oxidized to hydroxyplastoquinone-9 [PQ(OH)-9]. We provide here evidence that oxidation of PQ(OH)-9 by 1 O2 results in the formation of trihydroxyplastoquinone-9 [PQ(OH)3 -9]. It is concluded here that PQH2 -9 serves as an efficient 1 O2 chemical quencher in Arabidopsis, and PQ(OH)3 -9 can be considered as a natural product of 1 O2 reaction with PQ(OH)-9. The understanding of the mechanisms underlying 1 O2 chemical quenching provides information on the role of plastoquinols and their oxidation products in the response of plants to photooxidative stress.

19.
Eur J Gastroenterol Hepatol ; 27(4): 405-11, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25874513

RESUMO

BACKGROUND: Multiple studies have recently proposed the lowering of upper limit of normal (ULN) for alanine aminotransferase (ALT) to improve the diagnostic sensitivity for viral hepatitides and metabolic syndrome (MS). We have tried to validate some of the proposed ULNs in the diagnosis of MS. METHODS: We used data from the HepaMeta Study conducted in 2011 in Slovakia, which explored the prevalence of MS in eastern Slovakia. Patients were tested for the criteria of MS and ALT. Different, previously published, ALT cutoffs were then used to calculate odds' ratios, sensitivity, specificity, and accuracy of MS and its components. RESULTS: Manufacturers' recommended ULN used in our institution (0.8 µkat/l, 47 U/l for men and 0.6 µkat/l, 35 U/l for women) failed to predict any significant risk of MS. Lowered cutoff (72% of the original ULN) identified the patients with the highest age-adjusted probability of MS (odds ratio 3.194, 95% confidence interval 1.398-7.295). ALT was significantly associated with elevated levels of triacylglycerols, hyperglycemia, and obesity. CONCLUSION: In patients with MS, one must consider liver involvement if the patient has ALT levels in the upper third of the reference range. There is the need for discussion about the feasibility of lower ALT ULN in clinical practice.


Assuntos
Alanina Transaminase/sangue , Síndrome Metabólica/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/enzimologia , Pessoa de Meia-Idade , Razão de Chances , Padrões de Referência , Medição de Risco , Sensibilidade e Especificidade
20.
Sci Rep ; 5: 8882, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25744165

RESUMO

In this study, evidence is provided on the formation of electronically excited species in human multiple myeloma cells U266 in the growth medium exposed to hydrogen peroxide (H2O2). Two-dimensional imaging of ultra-weak photon emission using highly sensitive charge coupled device camera revealed that the addition of H2O2 to cell suspension caused the formation of triplet excited carbonyls (3)(R = O)*. The kinetics of (3)(R = O)* formation in the real time, as measured by one-dimensional ultra-weak photon emission using low-noise photomultiplier, showed immediate enhancement followed by a slow decay. In parallel to the formation of (3)(R = O)*, the formation of singlet oxygen ((1)O2) in U266 cells caused by the addition of H2O2 was visualized by the imaging of (1)O2 using the green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. Additionally, the formation of (1)O2 after the addition of H2O2 to cell suspension was detected by electron paramagnetic resonance spin-trapping spectroscopy using 2,2,6,6-tetramethyl-4-piperidone. Presented results indicate that the addition of H2O2 to cell suspension results in the formation of (3)(R = O)* and (1)O2 in U266 cell suspension. The contribution of the cell-free medium to the formation of electronically excited species was discussed.


Assuntos
Fenômenos Eletrofisiológicos , Peróxido de Hidrogênio/metabolismo , Mieloma Múltiplo/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Microscopia Confocal , Espécies Reativas de Oxigênio/metabolismo , Células Tumorais Cultivadas
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