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1.
Allergy ; 79(7): 1687-1707, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38174413

RESUMO

Acute respiratory infections are a major cause of morbidity and mortality in children worldwide. Dietary and nutritional interventions, including minerals and vitamin supplementation, have been explored as potential treatments for these infections. However, the evidence on their efficacy is limited and inconclusive. This systematic review and meta-analysis aim to provide a comprehensive summary of the available evidence on the effectiveness of dietary and nutritional interventions for treating acute respiratory tract infections in children. A systematic review was conducted according to the PRISMA 2020 guidelines in April 2022 and updated in April 2023. Clinical trials focusing on dietary or nutritional interventions, including supplementations, in children with acute respiratory tract infections were included. The selection of interventions and outcomes was based on biological plausibility. Data were extracted using a standardized form, and the risk of bias was assessed using the Cochrane Risk of Bias Tool. Meta-analysis was performed using random-effect models. A total of 50 studies were included in the review. Four trials were conducted in low, 32 in lower-middle, 12 in upper-middle, and only two in high-income countries. The studies evaluated various dietary interventions, including zinc, vitamin A, vitamin E, vitamin D, and probiotics. The results of individual studies on the efficacy of these interventions were mixed, with some showing positive effects on clinical outcomes such as duration of symptoms, while others showed no significant impact. Meta-analysis was conducted for zinc supplementation in children with pneumonia, and the pooled results suggested a potential limited benefit in terms of reduced hospital length of stay but not time to recovery. Meta-analyses on vitamin D did not show any effect in children with pneumonia. This systematic review fills a critical gap in the literature by synthesizing the available evidence on the efficacy and safety of nutritional or dietary interventions for acute respiratory tract infections in children. The findings indicate no dietary or nutritional intervention can currently be recommended for the routine treatment of respiratory tract infections in children based on single supplement studies. The metanalysis suggests that zinc supplementation might have a beneficial effect on length of hospitalization in children with pneumonia. New studies are needed to establish more conclusive evidence for pediatric acute respiratory diseases especially for children living in a context of high-income countries.


Assuntos
Suplementos Nutricionais , Infecções Respiratórias , Humanos , Criança , Doença Aguda , Resultado do Tratamento , Pré-Escolar , Vitaminas/administração & dosagem , Vitaminas/uso terapêutico
2.
J Chem Phys ; 160(22)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38856071

RESUMO

The shape of Janus particles is directly connected to their adsorption behavior. Janus tadpole polymers offer a unique topological architecture that includes competition between entropic, enthalpic, and topological terms in the adsorption free energy; accordingly, non-trivial adsorption behavior patterns are expected. We study the surface adsorption of Janus tadpole polymers by means of Monte Carlo simulations, finding that, depending on which part of the tadpole polymers is preferentially adsorbing on the surface, very different types of behavior for both the adsorbed polymeric phase and of the brush arise. The adsorbed phase and the brush mutually influence each other, leading to a variety of phenomena such as nematic ordering of the adsorbed stiff tadpole tails and intriguing changes in the territoriality of adsorbed ring polymers on the surface. We analyze in detail our findings, revealing the mechanisms behind the organization and ordering, and opening up new possibilities to tune and control the structure of such systems.

3.
Anal Chem ; 92(11): 7800-7807, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32367708

RESUMO

In this work, comparative studies on DNA-PNA and polyarginine-conjugated DNA-PNA duplexes unzipping inside the α-hemolysin nanopore (α-HL) are presented. We identified significant differences in the blockade currents, as the applied voltage across the nanopore facilitated the duplex capture inside the nanopore's vestibule against the constriction region, subsequent cDNA strand insertion inside the nanopore's ß-barrel past the constriction site, its complete unzip from the duplex, and translocation. We observed that inside the voltage-biased nanopore, polyarginine-conjugated DNA-PNA duplexes dehybridize faster than their DNA-PNA counterparts and proposed a model to describe the duplex unzipping. This study identifies key particularities of DNA-PNA duplex unzipping as it takes place inside the nanopore and being preceded by entrapment in the vestibule domain of the α-HL. Our results are a crucial step toward understanding the nucleic acids duplexes unzipping kinetics variability, in confined, variable geometries.


Assuntos
DNA/química , Proteínas Hemolisinas/análise , Nanoporos , Ácidos Nucleicos Peptídicos/química , Peptídeos/química , Cinética
4.
Soft Matter ; 15(17): 3527-3540, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30944917

RESUMO

The equilibrium properties of block copolymer star networks (BCS) are studied via computer simulations. We employ both molecular dynamics and multiparticle collisional dynamics simulations to investigate the self-organization of BCS with f = 9 functionalized arms close to their overlap concentrations under conditions of different fractions of functionalization and varying attraction strength. We find three distinct macroscopic self-organized states depending on fraction of attractive end-monomers and the strength of the attraction. At weak attractions, ergodic, diffusive liquids result, with short-lived bonds between the stars. As the attraction strength grows, the whole system forms a percolating cluster, while at the same time the individual molecules are diffusive. Finally, arrested gels emerge when the attractions become strong. The conformation of the BCS in these solutions is found to be strongly affected by the concentration, with the stars assuming typically spherical, open configurations in seeking to maximize inter-star associations as opposed to the inter-star collapse that results at infinite dilution, giving rise to strongly aspherical shapes and reduced sizes.

5.
Med Sci Monit ; 25: 5087-5097, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31287810

RESUMO

BACKGROUND Curcumin is an antioxidant that reduces inflammation and pain. This study aimed to assess the effect of pretreatment with naproxen and liposomal curcumin compared with naproxen and curcumin solution on oxidative stress parameters and pain in a rat model of migraine. MATERIAL AND METHODS Sixty-three male Wistar rats included a control group (n=9) and a rat model of migraine (n=54) induced by intraperitoneal injection of nitroglycerin (1 mg/0.1 kg). The rat model group was divided into an untreated control group (n=9), a group pretreated with naproxen alone (2.8 mg/kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with curcumin solution (1 mg/0.1 kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with curcumin solution (2 mg/0.1 kg) (n=9), a group pretreated with naproxen (2.8 mg/kg) combined with liposomal curcumin solution (1 mg/0.1 kg) (n=9) a group pretreated with naproxen (2.8 mg/kg) combined with liposomal curcumin solution (2 mg/0.1 kg) (n=9). Spectroscopy measured biomarkers of total oxidative status and nociception was tested using an injection of 1% of formalin into the rat paw. RESULTS Expression of biomarkers of oxidative stress and enhanced nociception were significantly increased following pretreatment with combined naproxen and liposomal curcumin compared with curcumin solution or naproxen alone (P<0.001). Combined curcumin solution and naproxen were more effective at a concentration of 2 mg/0.1kg for the first nociceptive phase (P<0.005). CONCLUSIONS In a rat model of migraine, combined therapy with liposomal curcumin and naproxen showed an improved antioxidant effect and anti-nociceptive effect.


Assuntos
Curcumina/farmacologia , Transtornos de Enxaqueca/tratamento farmacológico , Naproxeno/farmacologia , Animais , Antioxidantes/farmacologia , Curcumina/metabolismo , Modelos Animais de Doenças , Quimioterapia Combinada/métodos , Inflamação/tratamento farmacológico , Masculino , Transtornos de Enxaqueca/metabolismo , Naproxeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Dor/tratamento farmacológico , Medição da Dor/métodos , Ratos , Ratos Wistar
6.
Molecules ; 24(5)2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30818888

RESUMO

Curcumin (CC) is known to have anti-inflammatory and anti-oxidative properties and has already been tested for its efficiency in different diseases including diabetes mellitus (DM). New formulations and route administration were designed to obtain products with higher bioavailability. Our study aimed to test the effect of intraperitoneal (i.p.) administration of liposomal curcumin (lCC) as pre-treatment in streptozotocin(STZ)-induced DM in rats on oxidative stress, liver, and pancreatic functional parameters. Forty-two Wistar-Bratislava rats were randomly divided into six groups (seven animals/group): control (no diabetes), control-STZ (STZ-induced DM -60 mg/100g body weight a single dose intraperitoneal administration, and no CC pre-treatment), two groups with DM and CC pre-treatment (1mg/100g bw-STZ + CC1, 2 mg/100g bw-STZ + CC2), and two groups with DM and lCC pre-treatment (1 mg/100g bw-STZ + lCC1, 2 mg/100g bw-STZ + lCC1). Intraperitoneal administration of Curcumin in diabetic rats showed a significant reduction of nitric oxide, malondialdehyde, total oxidative stress, and catalase for both evaluated formulations (CC and lCC) compared to control group (p < 0.005), with higher efficacy of lCC formulation compared to CC solution (p < 0.002, excepting catalase for STZ + CC2vs. STZ + lCC1when p = 0.0845). The CC and lCC showed hepatoprotective and hypoglycemic effects, a decrease in oxidative stress and improvement in anti-oxidative capacity status against STZ-induced DM in rats (p < 0.002). The lCC also proved better efficacy on MMP-2, and -9 plasma levels as compared to CC (p < 0.003, excepting STZ + CC2 vs. STZ + lCC1 comparison with p = 0.0553). The lCC demonstrated significantly better efficacy as compared to curcumin solution on all serum levels of the investigated markers, sustaining its possible use as adjuvant therapy in DM.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Curcumina/farmacologia , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Lipossomos/administração & dosagem , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Curcumina/administração & dosagem , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Hipoglicemiantes/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Estresse Oxidativo , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Ratos , Ratos Wistar
7.
Biomed Chromatogr ; 32(5): e4176, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29265479

RESUMO

Fenspiride hydrochloride (FNS) is used in treating chronic inflammatory diseases, most commonly as a liquid oral solution. FNS produces degradation products along with fenspiride N-oxide (FNO) and 1-phenylethyl-4-hydroxy-4-aminomethyl piperidine hydrochloride (PHAP). We aimed to develop and validate a chromatographic method in order to identify the main degradation products in the presence of other compounds from a liquid preparation. The method used a dual gradient using two buffer solutions: the first with pH 4.5 (buffer 1, pH 4.5-MeOH 90:10%, v/v) and the second with pH 2.9 (buffer 2, pH 2.9-acetronitrile-methanol, 65:15:10%, v/v/v). As mentioned, there was a modification of the organic mixture, starting with 10% methanol and ending with a mixture of acetonitrile-methanol (15:10%, v/v). The flow-rate was 1.5 mL/min. According to the elution program, experimental conditions started with 100% solution S1, which decreased to 0% and, simultaneously, solution S2 increased to 100% during the first 10 min and was maintained for a further 5 min. After 15 min, initial conditions were re-established. The linearity interval was 0.5-2 µg/mL and the minimum correlation coefficient was 0.999. The recovery factor was 100.47-103.17% and the limit of quantification was 0.19-0.332 µg/mL. Intra-day maximum precision was 4.08% for FNS and 2.65% for PHAP. This double-gradient mobile phase produced good specificity in relation to the degradation products of FNS and other constituents of the oral liquid formulation. Forced degradation studies revealed other related substances that were confirmed in mass balance analyses. Degradation products were confirmed in acidic, basic and oxidative media.


Assuntos
Contaminação de Medicamentos , Compostos de Espiro/análise , Compostos de Espiro/química , Acetonitrilas , Administração Oral , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa , Formas de Dosagem , Modelos Lineares , Metanol , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
BMC Evol Biol ; 17(1): 205, 2017 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-28841819

RESUMO

BACKGROUND: The systematic positions of the extinct insect orders Hypoperlida, Miomoptera and Permopsocida were enigmatic and unstable for nearly a century. The recent studies based on new material, especially from the Cenomanian Burmese amber, shed light on evolutionary history of Acercaria resolving Permopsocida as the stem group of Condylognatha. However, the knowledge of the remaining two orders differs significantly. RESULTS: In this study, we describe new specimens and evaluate morphology of various structures with emphasis on the mouthparts and wing venation. Our results are primary based on revisions of the type specimens with a proper delimitation of taxa Hypoperlida and Miomoptera followed by their significance for the evolutionary history of Acercaria. Three new genera as Belmomantis gen. nov., Elmomantis gen. nov., and Mazonopsocus gen. nov. are designated as members of Palaeomanteidae. The Pennsylvanian Mazonopsocus provides a minimum age for calibration, in accordance to the presence of crown acercarians during the late Carboniferous. CONCLUSIONS: This contribution demonstrates that Hypoperlida and Miomoptera are stem groups of Acercaria. The putative clade (Hypoperlida + Miomoptera) is appearing as potential sister group of (Psocodea + (Permopsocida + (Thripida + Hemiptera))).


Assuntos
Extinção Biológica , Fósseis , Hemípteros/classificação , Animais , Humanos , Filogenia , Asas de Animais/anatomia & histologia
9.
J Chem Phys ; 147(24): 244505, 2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29289139

RESUMO

We design a novel microscopic mean-field theory of inhomogeneous nematic liquid crystals formulated entirely in terms of the tensor order parameter field. It combines the virtues of the Landau-de Gennes approach in allowing both the direction and magnitude of the local order to vary, with a self-consistent treatment of the local free-energy valid beyond the small order parameter limit. As a proof of principle, we apply this theory to the well-studied problem of a colloid dispersed in a nematic liquid crystal by including a tunable wall coupling term. For the two-dimensional case, we investigate the organization of the liquid crystal and the position of the point defects as a function of the strength of the coupling constant.

10.
Cladistics ; 32(1): 54-81, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34732023

RESUMO

Orthoptera have been used for decades for numerous evolutionary questions but several of its constituent groups, notably crickets, still suffer from a lack of a robust phylogenetic hypothesis. We propose the first phylogenetic hypothesis for the evolution of crickets sensu lato, based on analysis of 205 species, representing 88% of the subfamilies and 71% tribes currently listed in the database Orthoptera Species File (OSF). We reconstructed parsimony, maximum likelihood and Bayesian phylogenies using fragments of 18S, 28SA, 28SD, H3, 12S, 16S, and cytb (~3600 bp). Our results support the monophyly of the cricket clade, and its subdivision into two clades: mole crickets and ant-loving crickets on the one hand, and all the other crickets on the other (i.e. crickets sensu stricto). Crickets sensu stricto form seven monophyletic clades, which support part of the OSF families, "subfamily groups", or subfamilies: the mole crickets (OSF Gryllotalpidae), the scaly crickets (OSF Mogoplistidae), and the true crickets (OSF Gryllidae) are recovered as monophyletic. Among the 22 sampled subfamilies, only six are monophyletic: Gryllotalpinae, Trigonidiinae, Pteroplistinae, Euscyrtinae, Oecanthinae, and Phaloriinae. Most of the 37 tribes sampled are para- or polyphyletic. We propose the best-supported clades as backbones for future definitions of familial groups, validating some taxonomic hypotheses proposed in the past. These clades fit variously with the morphological characters used today to identify crickets. Our study emphasizes the utility of a classificatory system that accommodates diagnostic characters and monophyletic units of evolution. Moreover, the phylogenetic hypotheses proposed by the present study open new perspectives for further evolutionary research, especially on acoustic communication and biogeography.

11.
Vet Anaesth Analg ; 43(4): 405-11, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26671878

RESUMO

OBJECTIVE: To determine whether the administration of intravenous (IV) lidocaine before the induction of anaesthesia in premedicated dogs reduces the cough response associated with endotracheal intubation and the propofol dose required. STUDY DESIGN: Prospective, randomized, blinded clinical study. ANIMALS: A total of 84 client-owned dogs, with American Society of Anesthesiology physical status I and II. METHODS: Dogs received intramuscular (IM) acepromazine 0.02 mg kg(-1) and methadone 0.3 mg kg(-1) and were randomly allocated to one of two groups: saline (group S) and lidocaine (group L). Five minutes before the induction of anaesthesia and 40-50 minutes after premedication, group L received lidocaine (1.5 mg kg(-1) ) and group S received an equal volume of saline solution, each administered slowly IV. Anaesthesia was induced with propofol, initially 2 mg kg(-1) IV over 40 seconds, and then in increments of 0.5 mg kg(-1) every 15 seconds to effect. The same investigator anaesthetized all cases, unaware of group allocation. The following parameters were recorded: pulse rate (PR), mean arterial pressure (MAP, oscillometry), respiratory rate (fR ), sedation score immediately before and 5 minutes after treatment, and total dose of propofol required. Differences in pulse rate, MAP and propofol dose were analysed using the two-sample t-test, coughing incidence was analysed with the chi-square test, and differences in sedation score were analysed with the Mann-Whitney test. RESULTS: After treatment, the incidence of coughing at endotracheal intubation was significantly reduced in group L compared with group S (21% versus 45%; p = 0.022). There was no significant difference between the groups with regard to propofol dose required for endotracheal intubation (p = 0.122), PR (p = 0.611), MAP (p = 0.508) or sedation score (p = 0.051). CONCLUSIONS AND CLINICAL RELEVANCE: IV lidocaine can decrease the incidence of cough during endotracheal intubation in dogs premedicated with acepromazine and methadone, but does not appear to have a sparing effect on the dose of propofol required for endotracheal intubation. Use of IV lidocaine, prior to induction of anaesthesia with propofol may be beneficial in dogs where coughing at intubation would be detrimental.


Assuntos
Anestésicos Locais/farmacologia , Tosse/veterinária , Doenças do Cão/prevenção & controle , Intubação Intratraqueal/veterinária , Lidocaína/farmacologia , Acepromazina/administração & dosagem , Analgésicos Opioides/administração & dosagem , Anestésicos Intravenosos , Anestésicos Locais/administração & dosagem , Animais , Pressão Arterial/efeitos dos fármacos , Pressão Sanguínea , Tosse/prevenção & controle , Cães , Antagonistas de Dopamina/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Hipnóticos e Sedativos , Intubação Intratraqueal/efeitos adversos , Lidocaína/administração & dosagem , Metadona/administração & dosagem , Medicação Pré-Anestésica/métodos , Medicação Pré-Anestésica/veterinária , Propofol , Estudos Prospectivos , Taxa Respiratória/efeitos dos fármacos
12.
Liver Int ; 35(12): 2547-55, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25974637

RESUMO

BACKGROUND & AIMS: Extrahepatic complications of cirrhosis increase the risk for decompensation of the liver disease and death. Previous studies show common pathogenetic mechanisms involved in the development of hepatopulmonary syndrome and cirrhotic cardiomyopathy. We aimed to assess the link between these entities and their effect on disease-related patient morbidity and mortality. METHODS: Seventy-four consecutive cirrhotic patients without prior history of cardiovascular and pulmonary disease were included in a prospective observational study. Routine blood work, arterial blood gas analysis, pulse oximetry measurements, N-terminal pro-brain natriuretic peptide levels and contrast enhanced echocardiography examination with tissue Doppler imaging were performed in all patients. Patients were followed up for a median of 6 months and disease-related adverse events and death were the main outcomes tested. Statistical analysis was conducted according to the presence of hepatopulmonary syndrome or cirrhotic cardiomyopathy. RESULTS: Hepatopulmonary syndrome was diagnosed in 17 patients (23%) and cirrhotic cardiomyopathy in 30 patients (40.5%). There was no association between the presence of cirrhotic cardiomyopathy and the existence of mild or moderate hepatopulmonary syndrome. No echocardiographic parameters were useful in predicting the presence of hepatopulmonary syndrome. N-terminal pro-brain natriuretic peptide levels and length of QT interval did not aid in diagnosis of cirrhotic cardiomyopathy. Neither entity had significant influence on disease-related outcomes in the follow-up period. CONCLUSIONS: Hepatopulmonary syndrome and cirrhotic cardiomyopathy are independent complications arising in cirrhosis and have a limited influence on morbidity and mortality on a pre-liver transplantation population.


Assuntos
Cardiomiopatias , Síndrome Hepatopulmonar , Cirrose Hepática , Idoso , Cardiomiopatias/diagnóstico , Cardiomiopatias/epidemiologia , Cardiomiopatias/etiologia , Ecocardiografia/métodos , Feminino , Seguimentos , Síndrome Hepatopulmonar/diagnóstico , Síndrome Hepatopulmonar/epidemiologia , Síndrome Hepatopulmonar/etiologia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/análise , Fragmentos de Peptídeos/análise , Valor Preditivo dos Testes , Prognóstico , Romênia/epidemiologia , Estatística como Assunto , Análise de Sobrevida
13.
Soft Matter ; 11(3): 608-14, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25435377

RESUMO

Using Monte Carlo simulations, we study rod-like lyotropic liquid crystals confined to a square slab-like geometry with lateral dimensions comparable to the length of the particles. We observe that this system develops linear defect structures upon entering the planar nematic phase. These defect structures flank a lens-shaped nematic region oriented along a diagonal of the square box. We interpret these structures as a compromise between the 2-fold order of the bulk nematic phase and the 4-fold order imposed by the lateral boundaries. A simple Onsager-type theory that effectively implements these competing tendencies is used to model the phase behavior in the center of the box and shows that the free-energy cost of forming the defect structures strongly offsets the transition-inducing effects of both the transverse and lateral confinement.

14.
Chem Biodivers ; 12(10): 1554-64, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26460560

RESUMO

The essential oil extracted by hydrodistillation from Romanian Artemisia annua aerial parts was characterized by GC/MS analysis, which allowed the identification of 94.64% of the total oil composition. The main components were camphor (17.74%), α-pinene (9.66%), germacrene D (7.55%), 1,8-cineole (7.24%), trans-ß-caryophyllene (7.02%), and artemisia ketone (6.26%). The antimicrobial activity of this essential oil was evaluated by determining the following parameters: minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), minimal fungicidal concentration (MFC), and minimal biofilm eradication concentration (MBEC). Moreover, the soluble virulence factors were quantified with different biochemical substrates incorporated in the culture media. The reference and resistant, clinical strains proved to be susceptible to the A. annua oil, with MICs ranging from 0.51 to 16.33 mg/ml. The tested essential oil also showed good antibiofilm activity, inhibiting both the initial stage of the microbial cell adhesion to the inert substratum and the preformed mature biofilm. When used at subinhibitory concentrations, the essential oil proved to inhibit the phenotypic expression of five soluble virulence factors (hemolysins, gelatinase, DNase, lipases, and lecithinases). Briefly, the present results showed that the A. annua essential oil contained antimicrobial compounds with selective activity on Gram-positive and Gram-negative bacterial strains as well as on yeast strains and which also interfere with the expression of cell-associated and soluble virulence factors.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Artemisia annua/química , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Componentes Aéreos da Planta/química , Romênia , Relação Estrutura-Atividade
15.
Mol Phylogenet Evol ; 71: 224-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24071559

RESUMO

The Podismini are melanopline grasshoppers with a Holarctic distribution and well represented in the Eurasian fauna. To investigate their controversial taxonomy and evolutionary history, we studied 86%, 78% and 33% respectively of the Eurasian, European and Asian Palaearctic genera (Otte, 1995; Eades et al., 2013). We reconstructed parsimony, maximum likelihood and Bayesian phylogenies using fragments of four genes (ITS1, 16S, 12S, CO2). We applied a Bayesian molecular clock to estimate the times of species divergence, and the event-based parsimony method to depict the biogeographic framework of the diversification. Our results suggest that the selected Eurasian Podismini constitute a monophyletic group inside the Melanoplinae, provided it includes the North American genus Phaulotettix. The clades proposed by the present study inside the Podismini do not fit the older morphological or cytological classifications, but are in agreement with more recent proposals. Furthermore, our results can be explained by a plausible biogeographic history in which the present geographical distribution of the Eurasian Podismini resulted from known changes, to the Cenozoic climate and vegetation, induced by major geological events including the genesis of high mountain chains (e.g., Himalayas, Altay, Alps) and large deserts (e.g., Gobi, Karakoum, Taklamakan), and the opening of marginal seas (e.g., Bering, Japanese and Yellow Seas).


Assuntos
Gafanhotos/genética , Filogenia , Animais , Teorema de Bayes , Funções Verossimilhança , Filogeografia , Análise de Sequência de DNA
16.
Drug Deliv ; 31(1): 2388624, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39152905

RESUMO

Methotrexate (MTX) is a folic acid antagonist routinely used in cancer treatment, characterized by poor water solubility and low skin permeability. These issues could be mitigated by using drug delivery systems, such as functionalized gold nanoparticles (AuNPs), known for their versatility and unique properties. This study aimed to develop multi-shell AuNPs functionalized with MTX for the improvement of MTX antitumoral, antioxidant, and biocompatibility features. Stable phosphine-coated AuNPs were synthesized and functionalized with tailored polyethylene glycol (PEG) and short-branched polyethyleneimine (PEI) moieties, followed by MTX covalent binding. Physicochemical characterization by UV-vis and Fourier-transform infrared spectroscopy (FTIR) spectroscopy, dynamic light scattering (DLS), scanning transmission electron microscopy (STEM), and X-ray photoelectron spectroscopy (XPS) confirmed the synthesis at each step. The antioxidant activity of functionalized AuNPs was determined using DPPH radical scavenging assay, ferric ions' reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC) assays. Biocompatibility and cytotoxicity were assessed using MTT and LDH assays on HaCaT human keratinocytes and CAL27 squamous cell carcinoma. MTX functionalized AuNPs demonstrated enhanced antioxidant activity and a pronounced cytotoxic effect on the tumoral cells compared to their individual components, highlighting their potential for improving cancer therapy.


Assuntos
Antioxidantes , Ouro , Nanopartículas Metálicas , Metotrexato , Metotrexato/farmacologia , Metotrexato/administração & dosagem , Metotrexato/química , Ouro/química , Humanos , Nanopartículas Metálicas/química , Antioxidantes/farmacologia , Antioxidantes/administração & dosagem , Linhagem Celular Tumoral , Polietilenoglicóis/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Polietilenoimina/química , Células HaCaT , Queratinócitos/efeitos dos fármacos
17.
Heliyon ; 10(4): e26047, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384565

RESUMO

Chronic wounds represent one of the complications that might occur from the disruption of wound healing process. Recently, there has been a rise in interest in employing nanotechnology to develop novel strategies for accelerating wound healing. The aim of the present study was to use a green synthesis method to obtain AgNPs/NaLS systems useful for wounds management and perform an in-depth investigation of their behavior during and post-synthesis as well as of their biological properties. The colloids obtained from silver nanoparticles (AgNPs) and commercial sodium lignosulfonate (NaLS) in a single-pot aqueous procedure have been fully characterized by UV-Vis, FT-IR, DLS, TEM, XRD, and XPS to evaluate the synthesis efficiency and to provide new insights in the process of AgNPs formation and NaLS behavior in aqueous solutions. The effects of various concentrations of NaLS (0-16 mg/mL) and AgNO3 (0-20 mM) and of two different temperatures on AgNPs formation have been analyzed. Although the room temperature is feasible for AgNPs synthesis, the short mixing at 70 °C significantly increases the speed of nanoparticle formation and storage stability. In all experimental conditions AgNPs of 20-40 nm in size have been obtained. The antimicrobial activity assessed quantitatively on clinical and reference bacterial strains, both in suspension and biofilm growth state, revealed a broad antimicrobial spectrum, the most intensive inhibitory effect being noticed against Pseudomonas aeruginosa and Escherichia coli strains. The AgNP/NaLS enhanced the NO extracellular release, potentially contributing to the microbicidal and anti-adherence activity by protein oxidation. Both AgNP/NaLS and NaLS were non-hemolytic (hemolytic index<5%, 2.26 ± 0.13% hemolysis) and biocompatible (102.17 ± 3.43 % HaCaT cells viability). The presence of AgNPs increased the antioxidative activity and induced a significant cytotoxicity on non-melanoma skin cancer cells (62.86 ± 8.27% Cal-27 cells viability). Taken together, all these features suggest the multivalent potential of these colloids for the development of novel strategies for wound management, acting by preventing infection-associated complications and supporting the tissue regeneration.

18.
Eur J Gastroenterol Hepatol ; 36(1): 83-88, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37942741

RESUMO

BACKGROUND AND AIMS: Inflammation underpinning acute decompensation (AD) of liver disease is an important driver for the development of acute-on-chronic liver failure or death. We aimed to investigate associations between inflammatory biomarkers and impaired cardiac function in patients admitted for AD of cirrhosis. METHODS: This is a retrospective analysis of a well-characterized prospective cohort of patients with AD of liver disease admitted to a tertiary referral center. All patients had echocardiographic assessment of cardiac function and serum samples at admission. We reclassified patients according to the CLIF-C AD score, measured inflammatory (IL-6, IL-8, TNF-ɑ, CD206) and cardiac-specific (NT-proBNP, troponin T) biomarkers and tested for associations with echocardiographic parameters of cardiac function. We explored the impact on outcome of these factors in multivariate analysis. RESULTS: We included 70 patients (58 ±â€…10 years, 28 women), with a mean CLIF-C AD score of 47 ±â€…7. Thirty-nine patients (56%) fulfilled the echocardiographic criteria for cardiac dysfunction. We found associations between parameters of diastolic dysfunction and serum concentrations of IL-6 and CD206. Echocardiographic parameters of cardiac function were not associated with markers of liver dysfunction such as the CLIF-C AD score. In multivariate analysis higher MELD, higher NT-proBNP, and IL-8 concentrations as well as the absence of echocardiographic criteria for cardiac dysfunction significantly associated with death during follow-up. CONCLUSION: We found evidence in favor of a clinically relevant link between serum biomarkers of inflammation (IL-6, CD206) and echocardiographic signals of cardiac dysfunction in patients with acutely decompensated cirrhosis.


Assuntos
Insuficiência Hepática Crônica Agudizada , Cardiopatias , Humanos , Feminino , Prognóstico , Estudos Prospectivos , Interleucina-6 , Interleucina-8 , Estudos Retrospectivos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Biomarcadores , Inflamação/complicações
20.
Future Med Chem ; 15(15): 1369-1391, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37577781

RESUMO

Aim: A series of new hybrid molecules with two iodine atoms on the sides were synthesized. Methods: A one-pot, two-component method with trifluoroacetic acid as an effective catalyst to obtain dihydro-pyrrol-2-one compounds was developed. Short reaction times, a cheap catalyst, high yields and clean work-up are benefits of this method. Results: The chemical structures of the newly synthesized compounds were verified through spectroscopic techniques. Their antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans was tested in vitro. Conclusion: NC- and OH- radicals confer broad-spectrum antimicrobial activity, including against Gram-positive and Gram-negative bacteria and yeasts. Compounds 3g >7 and >9 were most active on the two bacterial species, while 3l >9 and >3i were most active against the fungal strain.

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