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1.
Front Public Health ; 12: 1330801, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38362220

RESUMO

Introduction: The online misinformation might undermine the vaccination efforts. Therefore, given the fact that no study specifically analyzed online vaccine related content written in Romanian, the main objective of the study was to detect and evaluate tweets related to vaccines and written in Romanian language. Methods: 1,400 Romanian vaccine related tweets were manually classified in true, neutral and fake information and analyzed based on wordcloud representations, a correlation analysis between the three classes and specific tweet characteristics and the validation of several predictive machine learning algorithms. Results and discussion: The tweets annotated as misinformation showed specific word patterns and were liked and reshared more often as compared to the true and neutral ones. The validation of the machine learning algorithms yielded enhanced results in terms of Area Under the Receiver Operating Characteristic Curve Score (0.744-0.843) when evaluating the Support Vector Classifier. The predictive model estimates in a well calibrated manner the probability that a specific Twitter post is true, neutral or fake. The current study offers important insights regarding vaccine related online content written in an Eastern European language. Future studies must aim at building an online platform for rapid identification of vaccine misinformation and raising awareness for the general population.


Assuntos
Comunicação , Vacinas , Humanos , Romênia , Idioma , Algoritmos
2.
Int J Mol Sci ; 22(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34281235

RESUMO

Multiple sclerosis (MS) is a demyelinating, autoimmune disease that affects a large number of young adults. Novel therapies for MS are needed considering the efficiency and safety limitations of current treatments. In our study, we investigated the effects of venlafaxine (antidepressant, serotonin-norepinephrine reuptake inhibitor), risperidone (atypical antipsychotic) and febuxostat (gout medication, xanthine oxidase inhibitor) in the cuprizone mouse model of acute demyelination, hypothesizing an antagonistic effect on TRPA1 calcium channels. Cuprizone and drugs were administered to C57BL6/J mice for five weeks and locomotor activity, motor performance and cold sensitivity were assessed. Mice brains were harvested for histological staining and assessment of oxidative stress markers. Febuxostat and metabolites of venlafaxine (desvenlafaxine) and risperidone (paliperidone) were tested for TRPA1 antagonistic activity. Following treatment, venlafaxine and risperidone significantly improved motor performance and sensitivity to a cold stimulus. All administered drugs ameliorated the cuprizone-induced deficit of superoxide dismutase activity. Desvenlafaxine and paliperidone showed no activity on TRPA1, while febuxostat exhibited agonistic activity at high concentrations. Our findings indicated that all three drugs offered some protection against the effects of cuprizone-induced demyelination. The agonistic activity of febuxostat can be of potential use for discovering novel TRPA1 ligands.


Assuntos
Febuxostat/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Neurotransmissores/uso terapêutico , Risperidona/uso terapêutico , Cloridrato de Venlafaxina/uso terapêutico , Animais , Corpo Caloso/efeitos dos fármacos , Cuprizona , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Febuxostat/farmacologia , Feminino , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Neurotransmissores/farmacologia , Risperidona/farmacologia , Canal de Cátion TRPA1/efeitos dos fármacos , Cloridrato de Venlafaxina/farmacologia
3.
Molecules ; 25(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941125

RESUMO

In a drug-repurposing-driven approach for speeding up the development of novel antimicrobial agents, this paper presents for the first time in the scientific literature the synthesis, physico-chemical characterization, in silico analysis, antimicrobial activity against bacterial and fungal strains in planktonic and biofilm growth state, as well as the in vitro cytotoxicity of some new 6,11-dihydrodibenz[b,e]oxepin-11(6H)one O-(arylcarbamoyl)oximes. The structures of intermediary and final substances (compounds 7a-j) were confirmed by 1H-NMR, 13C-NMR and IR spectra, as well as by elemental analysis. The in silico bioinformatic and cheminformatic studies evidenced an optimal pharmacokinetic profile for the synthesized compounds 7a-j, characterized by an average lipophilic character predicting good cell membrane permeability and intestinal absorption; low maximum tolerated dose for humans; potassium channels encoded by the hERG I and II genes as potential targets and no carcinogenic effects. The obtained compounds exhibited a higher antimicrobial activity against the planktonic Gram-positive Staphylococcus aureus and Bacillus subtilis strains and the Candida albicans fungal strain. The obtained compounds also inhibited the ability of S. aureus, B. subtilis, Escherichia coli and C. albicans strains to colonize the inert substratum, accounting for their possible use as antibiofilm agents. All the active compounds exhibited low or acceptable cytotoxicity levels on the HCT8 cells, ensuring the potential use of these compounds for the development of new antimicrobial drugs with minimal side effects on the human cells and tissues.


Assuntos
Anti-Infecciosos , Bactérias/crescimento & desenvolvimento , Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Candida albicans/fisiologia , Simulação por Computador , Oximas , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Biofilmes/crescimento & desenvolvimento , Linhagem Celular , Humanos , Oximas/química , Oximas/farmacologia
4.
Pharmaceutics ; 11(9)2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480671

RESUMO

Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system (CNS) through neurodegeneration and demyelination, leading to physical/cognitive disability and neurological defects. A viable target for treating MS appears to be the Transient Receptor Potential Ankyrin 1 (TRPA1) calcium channel, whose inhibition has been shown to have beneficial effects on neuroglial cells and protect against demyelination. Using computational drug discovery and data mining methods, we performed an in silico screening study combining chemical graph mining, quantitative structure-activity relationship (QSAR) modeling, and molecular docking techniques in a global prediction model in order to identify repurposable drugs as potent TRPA1 antagonists that may serve as potential treatments for MS patients. After screening the DrugBank database with the combined generated algorithm, 903 repurposable structures were selected, with 97 displaying satisfactory inhibition probabilities and pharmacokinetics. Among the top 10 most probable inhibitors of TRPA1 with good blood brain barrier (BBB) permeability, desvenlafaxine, paliperidone, and febuxostat emerged as the most promising repurposable agents for treating MS. Molecular docking studies indicated that desvenlafaxine, paliperidone, and febuxostat are likely to induce allosteric TRPA1 channel inhibition. Future in vitro and in vivo studies are needed to confirm the biological activity of the selected hit molecules.

5.
Toxicol Rep ; 5: 943-953, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30258789

RESUMO

In order to identify compounds with potential toxicity problems, particular attention is paid to structural alerts, which are high chemical reactivity molecular fragments or fragments that can be transformed via bioactivation by human enzymes into fragments with high chemical reactivity. The concept has been introduced in order to reduce the likelihood that future candidate substances as pharmaceuticals will have undesirable toxic effects. A significant proportion (∼78-86%) of drugs characterized by residual toxicity contain structural alerts; there is also evidence indicating the formation of active metabolites as a causal factor for the toxicity of 62-69% of these molecules. On the other hand, the pharmacological action of certain drugs depends on the formation of reactive metabolites. Detailed assessment of the potential for the formation of active metabolites is recommended to characterize a biologically active compound. Although many prescribed drugs frequently contain structural alerts and form reactive metabolites, the vast majority of these drugs are administered in low daily doses. Avoiding structural alerts has become almost a norm in new drug design. An in-depth review of the biochemical reactivity of these structural alerts for new drug candidates is critical from a safety point of view and is currently being monitored in the discovery of drugs. The chemical strategies applied to structural alerts in molecules to limit the toxicity are: •partial replacement or full replacement of the structural alert;•reduction of electronic density;•introduction of a structural element of metabolic interest (metabolic switching);•multiple approaches. Therefore, chemical intervention strategies to eliminate bioactivation are often interactive processes; their success depends largely on a close working relationship between drug chemists, pharmacologists and researchers in metabolic science.

6.
Rev. bras. farmacogn ; 28(1): 57-64, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898742

RESUMO

ABSTRACT This study evaluated the anti-inflammatory and antioxidant activities of Impatiens noli-tangere L., Balsaminaceae, and of Stachys officinalis L., Lamiaceae, polyphenolic-rich extracts obtained by nanofiltration process. Results showed the great potential and efficiency of the nanofiltration process to concentrate the herbal extract's main polyphenolic compounds (over 91% phenolic acids and flavonoids retention). S. officinalis polyphenolic-rich extracts had high antioxidant activities (IC50 2.5 µg/ml) compared to I. noli-tangere polyphenolic-rich extracts (IC50 19.3 µg/ml) and similar with that of ascorbic acid. Polyphenolic-rich extracts were investigated to determine the pro-inflammatory enzymes lipoxygenase, cyclooxygenase-1 and cyclooxygenase-2 and their inhibitory activity. Furthermore, high inhibitory activity of the examined extracts was reported for the first time, for both lipoxygenase (IC50 2.46 and 1.22 µg/ml for I. noli-tangere and S. officinalis polyphenolic-rich extracts, respectively), cyclooxygenase-1 (IC50 18.4 and 10.1 µg/ml for I. noli-tangere and S. officinalis polyphenolic-rich extracts, respectively) and cyclooxygenase-2 (IC50 = 1.9 and 1.2 mg/ml for I. noli-tangere and S. officinalis polyphenolic-rich extracts, respectively). Additionally, the in vivo studies showed that S. officinalis polyphenolic-rich extract has a higher anti-inflammatory effect, the hind-paw volume employed for both models determined that I. noli-tangere polyphenolic-rich extract and is also higher than that of diclofenac. It was noticed that their anti-inflammatory effect persists for more than 24 h. The I. noli-tangere and S. officinalis polyphenolic-rich extracts exert anti-inflammatory and antioxidant activities and these properties can be at least partly assigned to the presence of ursolic acid, caffeic acid, rosmarinic acid, quercetin and also anthocyanidins (genistin). The obtained results indicate the anti-inflammatory potential of the studied herbal extracts.

7.
Rom J Morphol Embryol ; 58(2): 507-516, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28730237

RESUMO

BACKGROUND AND AIMS: Experimental research and clinical data support the potential combination therapy for the treatment of neuropathic pain. We aimed to investigate the analgesic effect of the following associations: gabapentin + etifoxine; tramadol + etifoxine; gabapentin + tramadol, in an experimental model of peripheral neuropathy induced by paclitaxel. MATERIALS AND METHODS: Neuropathy was induced in male Wistar rats by the daily administration of 2 mg÷kg body weight (bw) paclitaxel intraperitoneally, four days in a row. Analgesics were given concomitantly with paclitaxel, in the following doses: tramadol 15 mg÷kg bw, etifoxine 100 mg÷kg bw, gabapentin 300 mg÷kg bw. Tactile allodynia and mechanical hyperalgesia were assessed using the Dynamic Plantar Aesthesiometer apparatus (Ugo Basile). After 18 days of treatment, the brain and liver tissue susceptibility to lipid peroxidation was evaluated and the sciatic nerve histological examination of the effect on myelin fibers was performed. RESULTS AND CONCLUSIONS: Experimental data have shown a strong analgesic effect of these three tested combinations expressed mainly by the statistically significant increased maximum response time, both in the assessment of allodynia and hyperalgesia. The gabapentin + tramadol combination lead to the maximum analgesic effect, immediately after the discontinuation of paclitaxel (44.94%, p<0.0001) and throughout the study. The treatment associated with tramadol caused a reduction in lipid peroxidation in the brain as compared to paclitaxel group. Combination therapy showed reduced damage to myelinated fiber density in the sciatic nerve. The drug combinations used in the experiment showed therapeutic potential in the fight against neuropathic pain induced by the administration of taxanes.


Assuntos
Combinação de Medicamentos , Neuralgia/induzido quimicamente , Paclitaxel/efeitos adversos , Animais , Modelos Animais de Doenças , Masculino , Neuralgia/tratamento farmacológico , Paclitaxel/farmacologia , Ratos , Ratos Wistar
8.
Rom J Morphol Embryol ; 57(3): 969-978, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28002512

RESUMO

BACKGROUND AND AIMS: Beta3-adrenergic receptors (beta3-ARs) have been initially characterized in 1989. Afterwards, their tissue distribution was established: white and brown adipose tissue, central nervous system, myocardium (atrial and ventricular), blood vessels, smooth gastrointestinal muscles (stomach, small intestine, colon), gallbladder, urinary bladder, prostate, skeletal muscles. Non-clinical trials have demonstrated the major implication of beta3-ARs in glucose metabolism, implicitly, in insulin release, and also in obesity. Therefore, new compounds were synthesized starting from beta-phenylethylamine nucleus and substituted in various positions, for possible antidiabetic and÷or antiobesity action. MATERIALS AND METHODS: In the present research, the antidiabetic action of newly synthesized compounds was investigated on an experimental model of alloxan-induced diabetes, administered in dose of 130 mg÷kg body weight (bw), intraperitoneally (i.p.). After 14 days of treatment, glycemia and enzymes involved in homeostasis of glucose metabolism, glucose-6-phosphate dehydrogenase (G6PD), glucose-6-phosphatase (G6Pase) and hexokinase were determined. Animals were then euthanized and histopathology examinations were performed on harvested liver, kidney, spleen and brain in order to document pathological changes induced by alloxan-induced diabetes and÷or by tested compounds. RESULTS AND CONCLUSIONS: Glycemia in animals treated with the tested compounds decreased statistically significant for groups C2 and C3 (-42.13% and -37.2%, respectively), compared to diabetic control group. C2 was also the compound to favorably modify the dynamics of determined enzymes, together with the display of very good safety profile supported by minor, non-significant, histopathological changes.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/metabolismo , Fenetilaminas/farmacologia , Receptores Adrenérgicos beta 3/metabolismo , Animais , Diabetes Mellitus/patologia , Humanos , Masculino , Ratos , Ratos Wistar
9.
Rom J Morphol Embryol ; 57(3): 1017-1023, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28002518

RESUMO

Pyrrolizidine alkaloids (PAs) are a class of toxic compounds which are found in plants. Poisoning caused by these toxins is associated with acute and chronic liver damage. Tussilago farfara (coltsfoot), Petasites hybridus (common butterbur), Senecio vernalis (eastern groundsel) and Symphytum officinale (comfrey) are traditional phytotherapic species, which beside the therapeutic bioactive compounds contain PAs. The aim of the paper was to assess the safety of some dry extracts obtained from these species. For the determination of acute toxicity, Organization for Economic Cooperation and Development (OECD) Guideline No. 423 was used. For the determination of repeated dose oral toxicity, Senecionis vernalis herba and Symphyti radix extracts (250 mg÷kg) were administrated, by gavage, for 28 days, and their effects on animal weight, liver and biliary functions, hepatic tissue and oxidative stress were investigated. After the acute toxicity testing, the dry extracts were placed in the GHS Category V (LD50>5000 mg÷kg, p.o.). For the subacute toxicity testing, no death or any signs of toxicity were observed. Also, no significant differences in biochemical parameters were observed between control and treated groups. The observed histopathological lesions were non-specific and were not consistent with the data reported in the literature for PAs exposure. In conclusion, the administration for 28 days, of the tested extracts, in a dose which correspond to a PAs concentration over the limits imposed in some countries, produced no hepatic and biliary toxic effects. Further studies, extended over a longer period of time, are needed in order to determine the safety of plant extracts containing PAs.


Assuntos
Extratos Vegetais/toxicidade , Alcaloides de Pirrolizidina/toxicidade , Administração Oral , Humanos , Extratos Vegetais/química , Alcaloides de Pirrolizidina/química
10.
Rom J Morphol Embryol ; 57(2 Suppl): 663-673, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27833957

RESUMO

BACKGROUND AND AIMS: Hyperforin (HY) is used to treat depression and skin irritation and has been shown a number of pharmacological activities. The literature does no cite data on changes that may occur in the body after HY intake (ethylene diammonium salt - EDS) in long-term administration. From this point of view, the present work is a key to determining the pharmacotoxicological profile of the HY-EDS, in long-term administration. MATERIALS AND METHODS: In present research, the influence of toxic doses of HY-EDS was investigated on the biochemical serum parameters and the histopathological changes in internal organs on the experimental mice model. For acute toxicity determination, the HY-EDS was tested in doses of 2000-5000 mg÷kg, administered once per day orally. For subacute toxicity, the HY-EDS was tested in three groups of mice, in doses of 50, 75 and 100 mg÷kg÷day, administered once daily, for 28 consecutive days. RESULTS AND CONCLUSIONS: As concern acute toxicity, a lethal effect has not occurred at any of the two tested doses and HY-EDS was classified as Class V toxic: median lethal dose (LD50) >5000 mg÷kg, p.o. After 14 days of follow-up in acute toxicity, the experimental results showed a statistically significant increase of aspartate transaminase (AST) and alanine transaminase (ALT), compared to the control group. There were no changes in creatinine and serum glucose compared to the control group. After the administration of repeated doses, it was observed an increase of serum transaminases and alkaline phosphatase. Histological examination revealed that the liver injuries were in an initial stage, making them reversible in case of HY-EDS treatment discontinuation. There was no evidence of kidney damage to any of the doses of HY-EDS.


Assuntos
Biomarcadores/metabolismo , Especificidade de Órgãos/efeitos dos fármacos , Floroglucinol/análogos & derivados , Terpenos/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Modelos Animais , Atividade Motora/efeitos dos fármacos , Floroglucinol/química , Floroglucinol/toxicidade , Terpenos/química , Testes de Toxicidade Aguda
11.
Rom J Morphol Embryol ; 57(4): 1261-1272, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28174792

RESUMO

BACKGROUND AND AIMS: Liver fibrosis is the increasingly accumulation of extracellular matrix (ECM), caused by chronic liver injuries, and represents a difficult clinical challenge in the entire world. Currently, the advanced knowledge of the cellular and molecular mechanisms of liver fibrosis showed that collagen-producing cells, like activated hepatic stellate cells (HSCs), portal fibroblasts and myofibroblasts are activated by fibrogenic cytokines, such as angiotensin II, transforming growth factor-beta 1 (TGF-ß1), and leptin. Because of these, we tested telmisartan, an angiotensin II (AT1) receptor blocker and a peroxisome proliferator-activated receptor-γ (PPARγ) partial agonist, for investigate its antifibrotic action, on experimental model of carbon tetrachloride-induced liver fibrosis. MATERIALS AND METHODS: In this research, we used two groups of Wistar rats, which received intraperitoneal (i.p.) injection of carbon tetrachloride (CCl4) 40% dissolved in olive oil, twice weekly for four consecutive weeks (initial dose of 5 mL÷kg, and other doses 3 mL÷kg). After one week, one group was received by gavage telmisartan (TS) dissolved in saline 0.9%, daily in dose of 8 mg÷kg, for 28 days. One group of Wistar rats was used for control. The antifibrotic action of telmisartan was investigated on the pathological changes of the liver and immunohistochemical analysis for hepatic stellate (Ito) cells (HSCs) reaction using anti-alpha-smooth muscle actin (anti α-SMA) antibody and macrophages cells (Kupffer cells) reaction using anti-CD68 antibody. RESULTS AND CONCLUSIONS: In group treated with telmisartan, hepatic fibrogenesis process was significantly reduced, in comparison with CCl4 group.


Assuntos
Anti-Hipertensivos/uso terapêutico , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Tetracloreto de Carbono/efeitos adversos , Cirrose Hepática/tratamento farmacológico , Animais , Anti-Hipertensivos/administração & dosagem , Benzimidazóis/administração & dosagem , Benzoatos/administração & dosagem , Feminino , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Ratos , Ratos Wistar , Telmisartan
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