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1.
J Physiol Pharmacol ; 74(5)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-38085514

RESUMO

Resveratrol is a polyphenolic phytocompound known to possess anxiolytic-like effects but its impact on central gammaaminobutyric acid (GABA) modulation has never been explored. The purpose of this study was to analyze the anxiolytic-like effects of resveratrol alone and in combination with rufinamide, an antiepileptic drug which has never been studied for its anxiolytic potential. The BALB/c mice were tested in a battery of behavior testing after administration of resveratrol (50 mg/kg) and rufinamide (50 mg/kg) alone and in combination. Moreover, molecular docking studies were also carried out to understand the interaction of resveratrol and rufinamide with GABA aminotransferase, GABA receptor and GABA-A transporter type 1. Resveratrol alone exerted notable anxiolytic-like effects and improved outcomes in few experiments but rufinamide alone did not yield any beneficial outcomes. However, the animal co-administered with resveratrol and rufinamide behaved exceptionally well (p<0.05) and preferred open, illuminated and exposed areas of open field, light/dark and elevated plus maze. Further, these animals showed reduced anxiety towards anxiogenic stimuli i.e. holes and marbles in hole board and marble bury tests, respectively. Resveratrol and rufinamide showed moderate to strong binding affinities with GABA proteins, indicating the potential to treat anxiety-like neurological disorders. Moreover, resveratrol and rufinamide were analyzed using molecular docking to determine their interaction with GABA receptors, transporters, and transaminase. The results suggest that their anxiolytic-like effects may be due to inhibiting GABA reuptake transporter 1 protein, leading to increased synaptic levels of GABA neurotransmitter, as seen in stable molecular dynamics results with the 7SK2 GABA transporter protein.


Assuntos
Ansiolíticos , Camundongos , Animais , Ansiolíticos/farmacologia , Resveratrol/farmacologia , Simulação de Acoplamento Molecular , Receptores de GABA-A/metabolismo , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/metabolismo , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Comportamento Animal
2.
Can J Psychiatry ; 68(12): 887-893, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37424267

RESUMO

The anniversary of the publication of 'One Flew Over the Cuckoo's Nest' by Ken Kesey offers an opportunity for reflection on the use of neurosurgery in psychiatry. We used a narrative, historical and dialectical method to deliver an account of the controversial subject. A balanced representation of the negative and positive aspects, acknowledging some of the questionable ethical practices while describing well-reasoned applications is provided. It includes neurosurgeons, psychiatrists who have embraced these procedures with unwarranted enthusiasm and those who have opposed. Neurosurgical techniques for the treatment of severe mental disorders have evolved from rudimentary procedures which were used to 'correct' unwanted behaviours associated with a wide range of severe mental disorders to more refined and selective approaches used as a last resort to treat specific mental health conditions. In the absence of specific aetiological models to guide ablative surgical targets, non-ablative, stimulatory techniques have more recently been developed to allow reversibility when surgical treatment fails to obtain a sizeable improvement in quality of life. The subject is concretely illustrated by two eloquent clinical images: one on a series of brain computed tomography scans carried out on a Canadian population of subjects, who underwent leukotomy decades ago, and the other more contemporary on an implantation surgery to epidural stimulation. Alongside technical advances in psychosurgery, a regulatory framework has gradually developed to ensure vigilance in the appropriateness of patients' selection. Nevertheless, harmonisation of protocols around the world is necessary to ensure consistency in obtaining and maintaining the highest possible ethical standards for the benefit of patients. If the neurosciences promise today, in their new, better framed, and reversible applications, to provide answers to unmet therapeutic needs, we still must remain attentive to drifts linked the introduction of intrusive technologies for purposes of domination or behaviour modification that would impede our individual freedom.


Assuntos
Dípteros , Transtornos Mentais , Psicocirurgia , Humanos , Animais , Psicocirurgia/história , Psicocirurgia/métodos , Qualidade de Vida , Canadá , Transtornos Mentais/cirurgia
3.
Braz J Biol ; 84: e259506, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197409

RESUMO

Scorpion venom contains a variety of neurotoxins which interact with ion channels and affect their activities. The present study was designed to evaluate the potential of scorpion venom as acetylcholinesterase (AChE) inhibitor by using Aedes aegypti as model organism. Venoms of two species, Hottentota tamulus (Fabricus, 1798) and Androctonus finitimus (Pocock, 1897) were selected for this study. Two peptides (36 kDa from H. tamulus and 54 kDa from A. finitimus) were separated from scorpion venom by using HPLC. Selected peptides caused significantly higher mortality in larvae and adults of Aedes aegypti than control (no mortalities were observed in control groups). Significant acetylcholinesterase (AChE) inhibitory potential of both peptides was recorded by spectrophotometer. The peptide of A. finitimus caused significantly higher mortality (95±1.53% in larvae and 100% in adults) than the peptide of H. tamulus (84.33±2.33% in larvae and 95.37±1.45% in adults). While H. tamulus peptide was more efficient in reducing AChE activity (0.029±0.012 in larvae and 0.03±0.003 in adults) than the peptide of A. finitimus (0.049±0.005 in larvae and 0.047±0.001 in adults). It was concluded that H. tamulus venom peptide was more efficiently reducing AChE activity, thus it could be a potential bio-insecticide which can be synthesized at industrial scale for the control of harmful insects.


Assuntos
Aedes , Inseticidas , Venenos de Escorpião , Acetilcolinesterase , Animais , Inseticidas/farmacologia , Larva , Peptídeos , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia
4.
J Physiol Pharmacol ; 72(4)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35072654

RESUMO

The increasing burden of neurological disorders is becoming a worldwide health challenge and researchers are continuously struggling to cure them by utilizing the miraculous medicinal properties of plants. The crude methanolic extract of whole herb of Phyla nodiflora (Pn.Cr) was subjected to phytochemical, antioxidant and neuropharmacological assessment. The Pn.Cr was initially exposed to the in vitro examination for phytocomposition through ultra-high performance liquid chromatography (UHPLC). The Sprague Dawley rats were chronically administered with various doses (100, 200 and 300 mg/kg) of Pn.Cr for one month with subsequent exposure to neurobehavioral and biochemical experimentation. The Pn.Cr exhibited a dose-dependent anxiolytic effect (P < 0.05 in comparison to control) as rats preferred central, illuminated and open arm zones in open field (OFT), light/dark (L/D) and elevated plus maze (EPM) tests. Likewise, scopolamine-induced amnesia was noticeably reversed with P < 0.05 by Pn.Cr as animals showed improved spontaneous alternation, discrimination index and shorter escape latencies in Y-maze, novel object recognition (NOR) and Morris water maze (MWM) tests. Subsequently, in vivo enzymatic assays depicted the reduced acetylcholinesterase and malondialdehyde levels. The levels of oxidative stress combating enzymes (glutathione peroxidase and superoxide dismutase) were increased in a dose-dependent style. The UHPLC detected 22 phytocompounds were further investigated in silico studied to predict the interaction of blood-brain barrier (BBB) crossing phytocompounds with human acetylcholinesterase. The four BBB crossing phytocompounds belonging to flavonoids, chalcones and alkaloids showed possible interaction with the target enzyme. We found that the phytocompounds owned by Pn.Cr might be playing multiple roles in modulation of different pathways to hinder the pathophysiology of neurological disorders including anxiety and Alzheimer's disease.


Assuntos
Acetilcolinesterase , Extratos Vegetais , Acetilcolinesterase/metabolismo , Animais , Antioxidantes , Cromatografia Líquida de Alta Pressão , Aprendizagem em Labirinto , Estresse Oxidativo , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
5.
J Physiol Pharmacol ; 71(4)2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33316769

RESUMO

The lithium-pilocarpine model in rats is commonly used to study the characteristic events of acute status epilepticus (SE), epileptogenesis and temporal lobe epilepsy (TLE). Here we investigated the impact of lacosamide alone and in combination with other drugs (pregabalin, piracetam and scopolamine) on spontaneous recurrent seizures (SRSs) and behavioral parameters during the time frame of 6 weeks after SE. In addition, the level of oxidative stress in the hippocampus was accessed by real-time microdialysis study (8-isoprostanes) and antioxidants enzymes in the homogenate. Results revealed severe behavioral deficits with the control epileptic group and animals displayed hyperexcitability, aggression apprehension and memory insufficiency. Pharmacological manipulation for 6 weeks with lacosamide (L) - 80 mg/kg; in polypharmacy with pregabalin (L/P) - 50/50 mg/kg and piracetam (L/Pi) - 50/140 mg/kg significantly (P < 0.05) ameliorated the anxiety-related behavior (open filed, elevated plus maze, light/dark tests), depression (forced swim test) and improved spatial/reference memory (Morris water maze). There were low incidences of seizures in L, L/P and L/Pi groups revealing disease-modifying effects of employed drugs. Furthermore, the chronic use of scopolamine (L/P/S; 50/50/2 mg/kg) as polypharmacy with the concept of antagonizing the cholinergic inputs in the epileptogenic phase aberrated the behavioral situation further worse. Treatments with L/P and L/Pi significantly attenuated (P < 0.05) the oxidative stress by reducing 8-isoprostanes and malondialdehyde (MDA) levels. Furthermore, superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels in the L/P group were significantly (P < 0.05) improved. Overall, our findings support the use of a combination of drugs (L/P and L/Pi) in lithium-pilocarpine model which remarkably ameliorated SRSs, reduced anxiety-related behaviors, retention of spatial/reference memory and lowered oxidative stress in a time-course evaluation 6 weeks post- SE insult.


Assuntos
Anticonvulsivantes/farmacologia , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Lacosamida/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estado Epiléptico/prevenção & controle , Animais , Biomarcadores/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Quimioterapia Combinada , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Teste de Campo Aberto/efeitos dos fármacos , Pilocarpina , Ratos Sprague-Dawley , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismo , Estado Epiléptico/psicologia , Natação , Fatores de Tempo
6.
Iran J Vet Res ; 19(2): 96-100, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30046319

RESUMO

Rumen Yeast® (RY; Saccharomyces cerevisiae), a live yeast strain, improves milk yield and composition and nutrients digestibility through balancing rumen ecosystem and increasing ruminal cellulolytic bacteria numbers in cattle. To examine the effects of dietary supplementation of RY in Nili-Ravi buffaloes, 16 buffaloes with 8 L average daily milk production were randomly divided into two groups, and investigated for a 60-day period. Group I (control) was offered maize silage ad libitum as sole forage plus 3 kg of concentrate/head per day (16% crude protein (CP) and 72% total digestible nutrients (TDN)), while group II was given the same diet as control supplemented with RY (14 g/head per day). Feed intake, nutrient digestibility, rumen fermentation and milk production of each animal were recorded. Average dry matter (DM) intake was not affected (P>0.05) in buffaloes with or without RY (14.7 and 14.3 kg/day, respectively). Digestibility of DM, CP, and ruminal pH were similar (P>0.05) between the groups, but the digestibility coefficients of neutral detergent fiber and acid detergent fiber were greater (P<0.05) for the animals that received RY. Milk production (9.60 vs. 9.15 L/day) and 4% fat corrected milk (FCM) (11.32 vs. 11.85 L/day) were significantly (P<0.05) greater in the buffaloes fed with RY than the control group. Milk composition was similar between the experimental groups, however, milk somatic cell count (SCC) was significantly (P<0.01) lower in RY supplemented buffaloes than the control animals. In conclusion, feeding RY had positive effects on milk production, fibre digestibility and SCC in buffaloes fed maize silage-concentrate based diet.

7.
Angew Chem Int Ed Engl ; 54(29): 8407-10, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26037244

RESUMO

The single-step preparation of highly ordered mesoporous silica hybrid nanocomposites with conjugated polymers was explored using a novel cationic 3,4-propylenedioxythiophene (ProDOT) surfactant (PrS). The method does not require high-temperature calcination or a washing procedure. The combination of self-assembly of the silica surfactant and in situ polymerization of the ProDOT tail is responsible for creation of the mesoporosity with ultralarge pores, large pore volume, and electroactivity. As this novel material exhibits excellent textural parameters together with electrical conductivity, we believe that this could find potential applications in various fields. This novel concept of creating mesoporosity without a calcination process is a significant breakthrough in the field of mesoporous materials and the method can be further generalized as a rational preparation of various mesoporous hybrid materials having different structures and pore diameters.

8.
Sci Rep ; 3: 1272, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23412079

RESUMO

Organic semiconductors constitute promising candidates toward large-scale electronic circuits that are entirely spintronics-driven. Toward this goal, tunneling magnetoresistance values above 300% at low temperature suggested the presence of highly spin-polarized device interfaces. However, such spinterfaces have not been observed directly, let alone at room temperature. Thanks to experiments and theory on the model spinterface between phthalocyanine molecules and a Co single crystal surface, we clearly evidence a highly efficient spinterface. Spin-polarised direct and inverse photoemission experiments reveal a high degree of spin polarisation at room temperature at this interface. We measured a magnetic moment on the molecule's nitrogen π orbitals, which substantiates an ab-initio theoretical description of highly spin-polarised charge conduction across the interface due to differing spinterface formation mechanisms in each spin channel. We propose, through this example, a recipe to engineer simple organic-inorganic interfaces with remarkable spintronic properties that can endure well above room temperature.

9.
J Nanosci Nanotechnol ; 11(9): 7783-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22097487

RESUMO

Europium doped cadmium sulphide (Cd(0.98)Eu(0.2)S) nanostructures were synthesised by chemical co-precipitation method using ethylene glycol (EG) and deionized water (Eu:CdS-1), and isopropyl alcohol (IPA) and deionized water (Eu:CdS-2) as mixed solvents. It has been found that the nanostructure of the europium doped CdS can be controlled by simply varying the mixed solvent system. Powder XRD pattern reveals the formation of hexagonal (wurtzite) and cubic (zinc blende) structure for Eu:CdS-1, and Eu:CdS-2, respectively. The crystallite size of the sample prepared using IPA and deionized water was measured to be 2.64 nm which is much smaller than that of the sample prepared using EG and deionized water as mixed solvent (3.65 nm). Morphology of the materials can also be changed from flower shaped crystals to paddy like structures by varying the mixed solvents. Band gap values of Eu3+ doped CdS nanocrystals synthesized from two different solvents were estimated using UV-reflectance spectra. The size and crystallinity of the samples were confirmed by HRTEM and SAED analysis. A significant change in the PL emission of the CdS nanocrystals was observed for the europium doped CdS which is mainly due to the presence of EU3+ ions which also play a significant role in the energy transfer process. It was also observed that the shift in the emission and efficiency depends on size and shape of the synthesised nanoparticles.

10.
Sci Technol Adv Mater ; 12(4): 044602, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27877410

RESUMO

We introduce a novel strategy of fabricating nanoporous carbons loaded with different amounts of CuO nanoparticles via a hard templating approach, using copper-containing mesoporous silica as the template and sucrose as the carbon source. The nature and dispersion of the CuO nanoparticles on the surface of the nanoporous carbons were investigated by x-ray diffraction (XRD), high-resolution scanning electron microscopy (HRSEM) and high-resolution transmission electron microscopy (HRTEM). XRD results reveal that nanoporous carbons with embedded CuO nanoparticles exhibit a well-ordered mesoporous structure, whereas the nitrogen adsorption measurements indicate the presence of excellent textural characteristics such as high surface area, large pore volume and uniform pore size distribution. The amount of CuO nanoparticles in the nanochannels of the nanoporous carbon could be controlled by simply varying the Si/Cu molar ratio of the mesoporous silica template. Morphological characterization by SEM and TEM reveals that high-quality CuO nanoparticles are distributed homogeneously within the nanoporous carbon framework. The supercapacitance behavior of the CuO-loaded nanoporous carbons was investigated. The material with a small amount of CuO in the mesochannels and high surface area affords a maximum specific capacitance of 300 F g-1 at a 20 mV s-1 scan rate in an aqueous electrolyte solution. A supercapacitor containing the CuO-loaded nanoporous carbon is highly stable and exhibits a long cycle life with 91% specific capacitance retained after 1000 cycles.

11.
Phys Rev Lett ; 105(7): 077201, 2010 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-20868071

RESUMO

We have studied the repercussion of the molecular adsorption mechanism on the electronic properties of the interface between model nonmagnetic or magnetic metallic surfaces and metallo-organic phthalocyanines molecules (Pcs). Our intertwined x-ray absorption spectroscopy experiments and computational studies reveal that manganese Pc (MnPc) is physisorbed onto a Cu(001) surface and retains the electronic properties of a free molecule. On the other hand, MnPc is chemisorbed onto Co(001), leading to a dominant direct exchange interaction between the Mn molecular site and the Co substrate. By promoting an interfacial spin-polarized conduction state on the molecule, these interactions reveal an important lever to tailor the spintronic properties of hybrid organic-metallic interfaces.

12.
J Phys Condens Matter ; 21(40): 405303, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21832410

RESUMO

X-ray absorption fine structure (XAFS) spectroscopy has been employed to investigate the cation distribution in nanocrystalline zinc ferrites (ZnFe(2)O(4)), synthesized in acidic and basic media at different temperatures. By using (Zn(1-x)Fe(x))[Ni(x)Fe(2-x)]O(4) as model compounds we have determined cation distribution in nanosize ZnFe(2)O(4). The cation distribution for samples synthesized at low temperature (400 °C) is (Zn(0.5)Fe(0.5))[Zn(0.5)Fe(1.5)]O(4) for urea- and (Zn(0.75)Fe(0.25))[Zn(0.25)Fe(1.75)]O(4) for citric-acid-based samples. These results show that samples synthesized at and above 600 °C have a local structural environment identical to that of bulk ZnFe(2)O(4).

14.
J Pak Med Assoc ; 47(12): 304-5, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9510642

RESUMO

To make bone marrow aspiration and trephine biopsy less painful and more acceptable in children a short acting anaesthetic ketamine was used in a dose of 1-2 mg/kg body weight intravenously or 4-5 mg/kg intramuscularly. One hundred cases aged 2 to 13 years were studied. The actual procedure time ranged between 20 seconds and 3 minutes, adequate samples were obtained in 80% of children on first attempt. Vomiting was the only side effect noted in two children. Ketamine is safe and recommended in all children undergoing bone marrow aspiration and trephine biopsies.


Assuntos
Anestésicos Dissociativos , Exame de Medula Óssea/métodos , Ketamina , Adolescente , Biópsia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
15.
Surg Endosc ; 8(12): 1431-3, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7878513

RESUMO

Traditionally the drainage of pancreatic pseudocysts has been carried out operatively, forming a cystenterostomy. A simple endoscopic method of forming a pancreatic cystogastrostomy with laser is presented. This procedure does not require a general anesthetic, is safe, and allows resolution of symptoms.


Assuntos
Endoscopia Gastrointestinal , Gastrostomia/métodos , Terapia a Laser/métodos , Pseudocisto Pancreático/cirurgia , Adulto , Drenagem/métodos , Feminino , Humanos , Masculino
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