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1.
Eur J Neurosci ; 53(12): 3988-4004, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32510674

RESUMO

Perineuronal nets (PNNs) represent a highly condensed specialized form of brain extracellular matrix (ECM) enwrapping mostly parvalbumin-positive interneurons in the brain in a mesh-like fashion. PNNs not only regulate the onset and completion of the critical period during postnatal brain development, control cell excitability, and synaptic transmission but are also implicated in several brain disorders including schizophrenia. Holes in the perineuronal nets, harboring the synaptic contacts, along with hole-surrounding ECM barrier can be viewed as PNN compartmentalization units that might determine the properties of synapses and heterosynaptic communication. In this study, we developed a novel open-source script for Fiji (ImageJ) to semi-automatically quantify structural alterations of PNNs such as the number of PNN units, area, mean intensity of PNN marker expression in 2D and 3D, shape parameters of PNN units in the ketamine-treated Sprague-Dawley rat model of schizophrenia using high-resolution confocal microscopic images. We discovered that the mean intensity of ECM within PNN units is inversely correlated with the area and the perimeter of the PNN holes. The intensity, size, and shape of PNN units proved to be three major principal factors to describe their variability. Ketamine-treated rats had more numerous but smaller and less circular PNN units than control rats. These parameters allowed to correctly classify individual PNNs as derived from control or ketamine-treated groups with ≈85% reliability. Thus, the proposed multidimensional analysis of PNN units provided a robust and comprehensive morphometric fingerprinting of fine ECM structure abnormalities in the experimental model of schizophrenia.


Assuntos
Ketamina , Esquizofrenia , Animais , Matriz Extracelular , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
2.
Phytother Res ; 32(2): 333-339, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29168254

RESUMO

In the previous experiments, the neuroprotective role of Iris tenuifolia Pall. (IT) in the model of middle cerebral artery occlusion (MCAO) was investigated. In addition, the concentrations of the cytokines tumour necrosis factor-alpha and interleukin-6 in blood plasma were measured. It was found that IT administered 1 hr prior to MCAO or immediately after MCAO reduced infarct volume significantly. IT application 1 and 4 hr after MCAO, respectively, was without any effect on infarct volume. There were no significant changes as regards tumour necrosis factor-alpha, whereas interleukin-6 concentrations were increased in blood plasma. This is the first evidence that flavonoids from Iris tenuifolia exert protective effects in the in vivo MCAO model. Our results suggest that these flavonoids are likely to be beneficial to humans by virtue of their ability to reduce infarct volume.


Assuntos
Dano Encefálico Crônico/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Etanol/química , Infarto da Artéria Cerebral Média/tratamento farmacológico , Interleucina-6/metabolismo , Gênero Iris/química , Acidente Vascular Cerebral/tratamento farmacológico , Fator de Necrose Tumoral alfa/metabolismo , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/patologia
3.
Eur Arch Psychiatry Clin Neurosci ; 267(5): 427-443, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28035472

RESUMO

The vasopressin- and oxytocin-degrading enzyme insulin-regulated aminopeptidase (IRAP) is expressed in various organs including the brain. However, knowledge about its presence in human hypothalamus is fragmentary. Functionally, for a number of reasons (genetic linkage, hydrolysis of oxytocin and vasopressin, its role as angiotensin IV receptor in learning and memory and others) IRAP might play a role in schizophrenia. We studied the regional and cellular localization of IRAP in normal human brain with special emphasis on the hypothalamus and determined numerical densities of IRAP-expressing cells in the paraventricular, supraoptic and suprachiasmatic nuclei in schizophrenia patients and controls. By using immunohistochemistry and Western blot analysis, IRAP was immunolocalized in postmortem human brains. Cell countings were performed to estimate numbers and numerical densities of IRAP immunoreactive hypothalamic neurons in schizophrenia patients and control cases. Shape, size and regional distribution of IRAP-expressing cells, as well the lack of co-localization with the glia marker glutamine synthetase, show that IRAP is expressed in neurons. IRAP immunoreactive cells were observed in the hippocampal formation, cerebral cortex, thalamus, amygdala and, abundantly, hypothalamus. Double labeling experiments (IRAP and oxytocin/neurophysin 1, IRAP with vasopressin/neurophysin 2) revealed that IRAP is present in oxytocinergic and in vasopressinergic neurons. In schizophrenia patients, the numerical density of IRAP-expressing neurons in the paraventricular and the suprachiasmatic nuclei is significantly reduced, which might be associated with the reduction in neurophysin-containing neurons in these nuclei in schizophrenia. The pathophysiological role of lowered hypothalamic IRAP expression in schizophrenia remains to be established.


Assuntos
Cistinil Aminopeptidase/metabolismo , Hipotálamo/enzimologia , Hipotálamo/patologia , Neurônios/enzimologia , Neuro-Hipófise/metabolismo , Esquizofrenia/patologia , Idoso , Autopsia , Doença Crônica , Feminino , Glutamato-Amônia Ligase/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neurofisinas/metabolismo , Ocitocina/metabolismo , Núcleo Hipotalâmico Paraventricular/patologia , Núcleo Supraquiasmático/patologia , Vasopressinas/metabolismo
4.
Mol Cell Biochem ; 421(1-2): 41-54, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27535238

RESUMO

Sciatic nerve irritation is often associated with disturbed Ca(2+) homeostasis in related neurons of the spinal cord. Since mitochondria substantially contribute to Ca(2+) homeostasis and little information is available, we studied the effects of loose sciatic nerve ligation, a chronic constriction injury (CCI), on neuronal mitochondria of the L3-L6 regions. Three groups of rats (untreated, sham operated, and ligated) were explored. For the characterization of mitochondria, specimens of the L3-L6 spinal cord regions were evaluated with respect to intracellular localization using pyruvate dehydrogenase immunohistochemistry and Mitotracker Red, and the ATP producing machinery by LC-MS/MS technique for the analysis of cardiolipin and high-resolution respirometry for the measurement of oxygen consumption. Therefore, the phospholipid cardiolipin supports electron transfer within the respiratory chain as part of mitochondrial respiration and is of high impact on the physical properties of the mitochondrial membrane system. Histological analysis of spinal cord motor neurons revealed clustering of mitochondria in ipsilateral samples from ligated animals 14 days after the insult. This phenomenon was similarly evident in the respective contralateral side. The intensity of MT-Red staining was enhanced exclusively at the ipsilateral side, indicating increased mitochondrial activity. CCI of the sciatic nerve caused massive changes in the composition of cardiolipin reflecting mitochondrial impairment in the early phase followed by regeneration processes as late response. Sciatic nerve CCI caused decrease in the capacity of mitochondrial ATP production that recovered within 14 days after treatment. In conclusion, we provide evidence that clustering of mitochondria, already verified for the spinal cord sensory neurons after CCI, also occurs in the respective motor neurons. Further we have demonstrated transient impairment of the capacity of mitochondrial ATP production in tissue samples. Stress-dependent changes in cardiolipin composition are sensitive markers and mediators of the response process including impairment and regeneration.


Assuntos
Cardiolipinas/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , Consumo de Oxigênio , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Medula Espinal/metabolismo , Animais , Masculino , Mitocôndrias/patologia , Neurônios/patologia , Ratos , Ratos Wistar , Nervo Isquiático/patologia , Medula Espinal/patologia
5.
BMC Complement Altern Med ; 14: 267, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-25066015

RESUMO

BACKGROUND: Valerian is commonly used for the treatment of insomnia and anxiety. Valerian extracts allosterically modulate GABA-A receptors and induced an anxiolytic activity. This activity is closely related to valerenic acid. In the present experiments it was investigated whether acetoxy valerenic acid may interfere with the anxiolytic action of valerenic acid. METHODS: Situational anxiety was measured using male CD-1 mice in the elevated plus maze test after oral administration of the test substances. In addition the body core temperature was measured. For the 3H-GABA binding assay dissected tissue from frontal cortex of male RjHan:WI rats were used. Statistical evaluation was performed by means of the non-parametric Kruskal-Wallies H-test, followed by the two-tailed Mann-Whitney U-test. RESULTS: Adding of acetoxy valerenic acid abolished the anxiolytic action of valerenic acid. There was no effect on body core temperature. Moreover, the valerian extract did not show any affinity to benzodiazepine binding sites. CONCLUSION: The determining compound for the observed anxiolytic effect of the valerian extract is its content of valerenic acid.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Indenos/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Valeriana/química , Animais , Ansiolíticos/química , Ansiolíticos/farmacocinética , Ansiedade/metabolismo , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Lobo Frontal/química , Lobo Frontal/metabolismo , Indenos/química , Indenos/farmacocinética , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacocinética , Ratos , Receptores de GABA-A/química , Receptores de GABA-A/efeitos dos fármacos , Sesquiterpenos/química , Sesquiterpenos/farmacocinética
6.
Brain Res ; 1838: 148994, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38729331

RESUMO

PTZ kindling induces oxidative stress, neuronal cell degeneration, and neurobehavioral alterations in rodents that mimic neuropsychiatric comorbidities of epilepsy, which could be initiated or aggravated by some antiepileptic drugs. Here, we investigated the effects of the methanol extract of Ficus platyphylla (FP) on severity scores for seizures, neuronal cell degeneration, and neurobehavioral alterations in rats kindled with pentylenetetrazole (PTZ) and probed the involvement of oxidative stress in these ameliorative effects of FP. FP (50 and 100 mg/kg, p.o.) ameliorated seizure severity, neuronal cell degeneration, depressive behaviors, cognitive dysfunctions, and oxidative stress in rats kindled with PTZ (42.5 mg/kg, i.p.). The findings from this study give additional insights into the potential values of FP in the treatment of persistent epilepsy and major neuropsychiatric comorbidities via modulation of oxidative stress.


Assuntos
Anticonvulsivantes , Ficus , Excitação Neurológica , Estresse Oxidativo , Pentilenotetrazol , Extratos Vegetais , Convulsões , Animais , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Excitação Neurológica/efeitos dos fármacos , Masculino , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Convulsões/induzido quimicamente , Ratos , Anticonvulsivantes/farmacologia , Ratos Wistar , Modelos Animais de Doenças , Comportamento Animal/efeitos dos fármacos , Epilepsia/tratamento farmacológico , Epilepsia/induzido quimicamente
7.
Drug Discov Today ; 28(5): 103527, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36792006

RESUMO

Whereas pharmaceutical co-crystals are widely described as tool to improve solubility and dissolution behavior of poorly soluble drugs, so far less focus has been on their potential role to facilitate pharmaceutical manufacturability. This review summarizes recent developments in co-crystal research regarding new trends in co-crystal preparation routes and control of solid-state material attributes. Also, recent literature was reviewed to assess risks for co-crystals in formulation processes. A growing number of publications suggest that co-crystals show potential to specifically improve mechanical properties such as tabletability and compressibility, which can often be linked to intrinsic features of crystal structure properties. However, such trends must be treated with care, as molecular structures in reported co-crystal studies are not representative in some structural parameters governing also solid-state behavior (smaller molecular weight, more balanced hydrogen bond donor versus acceptor counts) compared to recent market approved small molecule drugs.


Assuntos
Desenvolvimento de Medicamentos , Cristalização , Solubilidade , Preparações Farmacêuticas
8.
J Air Transp Manag ; 106: 102325, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36340887

RESUMO

This paper develops three scenarios for the aviation industry's recovery from COVID-19 until 2030 by utilizing the scenario methodology. Besides the short- and mid-term pandemic development, the study takes into account the industry's adaptation to changes in the market environment, e.g., toward sustainability and hygiene requirements. The resulting scenarios include the expected point in time of full air traffic recovery to pre-crisis levels. Subsequent implications suggest that most COVID-19-related hygiene measures along the travel chain disappear after the pandemic is contained. Some measures might serve as a differentiator between airline business models, while others are expected to become a new standard. Implications for environmental awareness and resulting operational and technical measures include changes in society's attitude toward traveling post-pandemic, especially in light of varying levels of environmental awareness. The presented scenarios help to identify the range of plausible development paths, thus building the basis for future model-based research.

9.
Small Methods ; 7(6): e2201692, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36965154

RESUMO

The crystal habit can have a profound influence on the physical properties of crystalline materials, and thus controlling the crystal morphology is of great practical relevance across many industries. Herein, this work investigates the effect of polymer additives on the crystal habit of metformin HCl with both experiments and computational methods with the aim of developing a combined screening approach for crystal morphology engineering. Crystallization experiments of metformin HCl are conducted in methanol and in an isopropanol-water mixture (8:2 V/V). Polyethylene glycol, polyvinylpyrrolidone, Tween80, and hydroxypropyl methylcellulose polymer additives are used in low concentrations (1-2% w/w) in the experiments to study the effect they have on modifying the crystal habit. Additionally, this work has developed computational methods to characterize the morphology "landscape" and quantifies the overall effect of solvent and additives on the predicted crystal habits. Further analysis of the molecular dynamics simulations is used to rationalize the effect of additives on specific crystal faces. This work demonstrates that the effects of additives on the crystal habit are a result of their absorption and interactions with the slow growing {100} and {020} faces.

10.
J Neurosci ; 31(39): 13890-6, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21957251

RESUMO

Morphine is one of the most potent analgesic drugs. However, the utility of morphine in the management of chronic pain is limited by its rapid development of tolerance. Morphine exerts all of its pharmacological effects via the µ-opioid receptor. In many systems, tolerance is associated with phosphorylation and desensitization of G-protein-coupled receptors (GPCRs). In case of the µ-opioid receptor, phosphorylation occurs in an agonist-selective manner. High-efficacy agonists such as [d-Ala(2)-MePhe(4)-Gly-ol]enkephalin (DAMGO), fentanyl, or etonitazene stimulate the phosphorylation of both C-terminal threonine 370 (T370) and serine 375 (S375). In contrast, morphine promotes the phosphorylation of S375 but fails to stimulate T370 phosphorylation. Here, we have assessed the contribution of S375 phosphorylation to the development of antinociceptive tolerance to high- and low-efficacy µ agonists in vivo. We show that S375 phosphorylation of the µ-opioid receptor occurs in intact mouse brain in a dose-dependent manner after administration of morphine, fentanyl, or etonitazene. In knock-in mice expressing the phosphorylation-deficient S375A mutant of the µ-opioid receptor, morphine and fentanyl exhibited greater dose-dependent antinociceptive responses than in wild-type mice. However, acute and chronic tolerance to morphine was retained in S375A mutant mice. In contrast, antinociceptive tolerance after repeated subcutaneous application of etonitazene or repeated intracerebroventricular application of DAMGO was diminished. Thus, tolerance to µ agonists with different efficacies develops through distinct pathways. Whereas tolerance induced by DAMGO or etonitazene requires agonist-driven phosphorylation of S375, the development and maintenance of antinociceptive tolerance to morphine occurs independent of S375 phosphorylation.


Assuntos
Analgésicos Opioides/farmacologia , Morfina/farmacologia , Medição da Dor/efeitos dos fármacos , Receptores Opioides mu/agonistas , Receptores Opioides mu/biossíntese , Alanina/genética , Animais , Tolerância a Medicamentos/fisiologia , Técnicas de Introdução de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Medição da Dor/métodos , Fosforilação/efeitos dos fármacos , Fosforilação/genética , Receptores Opioides mu/genética , Serina/genética
11.
Neural Plast ; 2012: 832757, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23150836

RESUMO

Schizophrenia is a complex psychiatric disorder. Although a number of different hypotheses have been developed to explain its aetiopathogenesis, we are far from understanding it. There is clinical and experimental evidence indicating that neurodevelopmental factors play a major role. Disturbances in neurodevelopment might result in alterations of neuroanatomy and neurochemistry, leading to the typical symptoms observed in schizophrenia. The present paper will critically address the neurodevelopmental models underlying schizophrenia by discussing the effects of typical and atypical antipsychotics in animal models. We will specifically discuss the vitamin D deficiency model, the poly I:C model, the ketamine model, and the postnatal ventral hippocampal lesion model, all of which reflect core neurodevelopmental issues underlying schizophrenia onset.


Assuntos
Antipsicóticos/farmacologia , Proliferação de Células/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Giro Denteado/citologia , Humanos , Esquizofrenia/etiologia , Esquizofrenia/fisiopatologia
12.
J Pharm Sci ; 111(1): 206-213, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34662544

RESUMO

Low solubility of drugs represents a major challenge during research and development. Ways to overcome this are either focused on formulation development or optimization of the molecular structure of the drug. The latter is not only governed by the constitution of the molecule but also by its stereochemistry. Development of enantiomers in contrast to racemic mixtures has become the state of the art over the last decades as this leads to higher potency and selectivity. Thus, enantiopure drugs require lower doses compared to their racemates. Additionally, selecting one enantiomer also leads to improved solubility of the drug compared to its racemic compound. While this effect is well known for enantiomers and racemic compounds where chirality is introduced via a chiral central atom, here we describe the first case where improved solubility is realized by selecting an axially chiral atropisomer.


Assuntos
Solubilidade , Estrutura Molecular , Estereoisomerismo
13.
J Ethnopharmacol ; 278: 114219, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34058316

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Extracts of the stem bark of Ficus paltyphylla (FP) are used in the Nigerian traditional medicine to manage psychoses, depression, epilepsy, pain, and inflammation. Our previous studies revealed that the methanol extract of FP ameliorate body core temperature. AIM OF THE STUDY: A number of pharmacological agents that utilize mechanisms that enhanced neuronal survival and/or neural regeneration have been developed for the treatment of stroke. Hypothermia protects the brain from damage caused by ischemia by attenuating destructive processes such as neuroinflammation, excitotoxicity, blood-brain barrier disruption, apoptosis, and free radical formation following cerebral ischemia. In the present study, we examined the neuroprotective potential of FP on permanent occlusion of the middle cerebral artery (MCAO)-induced ischemia in mice. MATERIAL AND METHODS: C57Bl mice were subjected to MCAO. FP was administered 1 h prior to and immediately after surgery. The brains were collected 24 h later and infarct volumes were measured using immune-histochemical staining, DAPI, NeuN, synaptophysin, and NR2B were quantified. RESULTS: Administration of FP prior to MCAO significantly reduced infarct volume, with no effect on infarct volume immediately after MCAO. Higher numbers of cells and neurons were observed in the peri-infarct area in both groups of mice. FP-induced hypothermia protected tissue in the peri-infarct region from synaptophysin reduction. NMDA receptor 2 (NR2B) immunoreactivity is enhanced by MCAO, with no difference observed in both sham-operated and FP-induced hypothermia groups of mice. CONCLUSIONS: The data suggest that FP might be useful in the reduction of ischemia-induced infarct volume when administered prior to the initiation of ischemia with no effect observed after ischemia induction.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Ficus/química , Hipotermia Induzida/métodos , Extratos Vegetais/farmacologia , Animais , Isquemia Encefálica/complicações , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média , Masculino , Metanol/química , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia
14.
Eur Arch Psychiatry Clin Neurosci ; 260(2): 151-62, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19579000

RESUMO

Altered neuroplasticity contributes to the pathophysiology of schizophrenia. However, the idea that antipsychotics may act, at least in part, by normalizing neurogenesis has not been consistently supported. Our study seeks to determine whether hippocampal cell proliferation is altered in adult rats pretreated with ketamine, a validated model of schizophrenia, and whether chronic administration with neuroleptic drugs (haloperidol and risperidone) affect changes of cell genesis/survival. Ketamine per se has no effect on cell proliferation. Its withdrawal, however, significantly induced cell proliferation/survival in the hippocampus. Risperidone and haloperidol supported cell genesis/survival as well. During ketamine withdrawal, however, their application did not affect cell proliferation/survival additionally. TUNEL staining indicated a cell-protective potency of both neuroleptics with respect to a ketamine-induced cell death. As RT-PCR and Western blot revealed that the treatment effects of risperidone and haloperidol seemed to be mediated through activation of VEGF and MMP2. The mRNA expression of NGF, BDNF, and NT3 was unaffected. From the respective receptors, only TrkA was enhanced when ketamine withdrawal was combined with risperidone or haloperidol. Risperidone also induced BCL-2. Ketamine withdrawal has no effect on the expression of VEGF, MMP2, or BCL-2. It activated the expression of BDNF. This effect was normalized by risperidone or haloperidol. The findings indicate a promoting effect of risperidone and haloperidol on survival of young neurons in the hippocampus by enhancing the expression of the anti-apoptotic protein BCL-2 and by activation of VEGF/MMP2, whereby an interference with ketamine and thus a priority role of the NMDA system was not evident.


Assuntos
Células-Tronco Adultas/efeitos dos fármacos , Antipsicóticos/farmacologia , Haloperidol/farmacologia , Hipocampo/citologia , Risperidona/farmacologia , Animais , Bromodesoxiuridina/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Modelos Animais , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
15.
J Mol Med (Berl) ; 86(5): 563-71, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18335189

RESUMO

Mental retardation is the most frequent cause of serious handicap in children and young adults. Mutations in the human angiotensin II type 2 receptor (AT2) have been implicated in X-linked forms of mental retardation. We here demonstrate that mice lacking the AT2 receptor gene are significantly impaired in their performance in a spatial memory task and in a one-way active avoidance task. As no difference was observed between the genotypes in fear conditioning, the detected deficit in spatial memory may not relate to fear. Notably, receptor knockout mice showed increased motility in an activity meter and elevated plus maze. Importantly, these mice are characterized by abnormal dendritic spine morphology and length, both features also found to be associated with some cases of mental retardation. These findings suggest a crucial role of AT2 in normal brain function and that dysfunction of the receptor has impact on brain development and ultrastructural morphology with distinct consequences on learning and memory.


Assuntos
Espinhas Dendríticas/patologia , Transtornos da Memória/metabolismo , Receptor Tipo 2 de Angiotensina/deficiência , Animais , Aprendizagem da Esquiva , Espinhas Dendríticas/ultraestrutura , Hipocampo/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor Tipo 2 de Angiotensina/metabolismo
16.
Ann Plast Surg ; 63(6): 661-4, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19887933

RESUMO

Financial and other competing interests have recently received increasing attention. In particular clinical research in plastic surgery attracts for-profit organizations, thus, explaining the increasing number of financial sponsorships. However, research articles often lack sufficient description of study design as well as disclosure of the source of funding. Furthermore, debate exists whether industry funding influences research findings and is leading to pro-industry results. A hand search was conducted identifying all randomized controlled (RCT) and controlled clinical trials (CCT) in 4 plastic surgery journals (Plastic and Reconstructive Surgery, British Journal of Plastic Surgery, Annals of Plastic Surgery, and Aesthetic Plastic Surgery) between 1990 and 2005. Subsequently, the influence of financial support on study outcome was analyzed. A total of 10,476 original articles were analyzed, resulting in the identification of 346 clinical trials which meet the Cochrane criteria for RCTs and CCTs. One hundred eighty-three trials and 163 studies were found to be RCTs and CCTs, respectively. Hereof, only 70 trials (20.2%) reported on grant support. Of these, 42 trials (60%) were supported by the industry. Depending on the topic addressed marked differences were detected regarding grant support. Studies with a focus on reconstructive plastic surgery were supported by the industry and by public institutions in almost equal shares (18 trials vs. 15 trials), whereas aesthetic surgical topics were predominantly funded by the industry (13 trials vs. 6 trials). Industry-funded trials reported more often statistically significant differences between treatment arms (28 trials vs. 16 trials). Authors' conclusions were found to be positively associated with financial competing interests. However, trial funding is rarely declared in the plastic surgery literature. Thus, the quality of reporting needs to be improved to be able to investigate these relationships in greater detail and draw more representative conclusions.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Apoio à Pesquisa como Assunto/economia , Cirurgia Plástica , Indústria Farmacêutica , Humanos , Avaliação de Resultados em Cuidados de Saúde , Publicações Periódicas como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Projetos de Pesquisa , Apoio à Pesquisa como Assunto/ética
17.
Ann Plast Surg ; 62(3): 293-6, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19240528

RESUMO

Although a myriad of original articles is published annually in plastic surgical journals assessment of the level of evidence-based medicine has rarely been conducted. A hand search was conducted identifying randomized controlled (RCTs) and controlled clinical trials in 3 plastic surgical journals from 1990 to 2005. The quality of reporting was assessed and additional parameters investigated including report of statistical significance, type of institution, and country affiliation of the first author. Nine thousand four hundred twenty-eight original articles were analyzed of which 172 and 139 articles met the inclusion criteria for RCTs and controlled clinical trials, respectively. Fifty-nine RCTs reported on successful double-blinding with only 20 RCTs reporting the allocation concealment appropriately. Description of participant drop-outs was detected in 64 RCTs and a statistically significant result was reported in 118 RCTs. The annual publication of controlled trials has increased over the last 16 years, with the majority of controlled trials being from North-America and Europe. Execution and publication of controlled trials has increased in the plastic surgical literature. However, the quality of reporting deserves improvement.


Assuntos
Ensaios Clínicos Controlados como Assunto , Medicina Baseada em Evidências , Editoração/normas , Cirurgia Plástica , Humanos , Jornalismo Médico , Editoração/estatística & dados numéricos , Controle de Qualidade , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Behav Brain Res ; 367: 215-220, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-30965062

RESUMO

Preparations of Ficus platyphylla are used in Nigeria's folk medicine to manage a variety of diseases, including insomnia, psychoses, depression, epilepsy, pain, and inflammation. In this study, we examined the effects of the standardised methanol extract of F. platyphylla stem bark (FP) on two-way active avoidance learning and body core temperature to complement earlier studies on the neuroleptic potential of this medicinal plant, which is already in common use. The extract did not interfere with the acquisition and consolidation of the conditioned avoidance reaction (CAR), but did diminish the retrieval of CAR. The extract dose-dependently reduced body core temperature; this was significantly ameliorated by the use of amphetamine. The results confirmed the neuroleptic-like efficacy of FP, probably via the modulation of dopaminergic neurons.


Assuntos
Antipsicóticos/farmacologia , Aprendizagem da Esquiva/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Ficus , Hipotermia/induzido quimicamente , Casca de Planta , Extratos Vegetais/farmacologia , Anfetamina/farmacologia , Animais , Antipsicóticos/administração & dosagem , Estimulantes do Sistema Nervoso Central/farmacologia , Relação Dose-Resposta a Droga , Hipotermia/tratamento farmacológico , Masculino , Consolidação da Memória/efeitos dos fármacos , Rememoração Mental/efeitos dos fármacos , Metanol , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/administração & dosagem , Solventes
19.
Eur J Neurosci ; 27(6): 1311-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18331339

RESUMO

It is established that hippocampal neurogenesis is dynamically regulated by physiological and pathological stimuli including learning, environmental complexity, mental disorders and brain lesion. Little is known about factors regulating adaptive changes in neurogenesis. Using mu-opioid receptor (MOP)-knockout mice we addressed whether endogenous opioids influence ischemia-induced enhancement of hippocampal neurogenesis. Permanent middle cerebral artery occlusion (MCAO) produced similar corticostriatal infarcts in MOP-knockout and wildtype mice. Analyses of BrdU/doublecortin-colabelled cells in the granule cell layer 14 days after MCAO showed that ischemic knockouts contained more immature neurons generated during days 9-11 than wildtypes. After 29 days, similar quantities of BrdU/NeuN-labelled cells were found in ischemic knockout and wildtype mice, suggesting that granule cells that were formed in excess during days 9-11 in the knockouts were eliminated by day 29. Neurogenesis was similar in knockout and wildtype mice subjected to sham operation. In addition to a transient increase in neurogenesis, MCAO caused a transient up-regulation of preprodynorphin and preproenkephalin mRNA expression in the granule cell layer. Our findings suggest that activated signalling via endogenous opioids and the MOP limits the enhanced generation of neuronal cells after ischemic corticostriatal lesions.


Assuntos
Diferenciação Celular/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Neurônios/citologia , Peptídeos Opioides/fisiologia , Receptores Opioides mu/fisiologia , Animais , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/prevenção & controle , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Neurônios/patologia , Peptídeos Opioides/genética , Receptores Opioides mu/agonistas , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo
20.
Psychoneuroendocrinology ; 33(3): 340-51, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18191906

RESUMO

The beacon gene is involved in the regulation of energy metabolism, food intake, and obesity. We localized its gene product, beacon-/ubiquitin 5-like immunoreactivity in brains of normal-weight, non-psychotic individuals, adipose (BMI over 32), non-psychotic individuals, and haloperidol-treated schizophrenics. The protein was found to be highly expressed in many neurons of the paraventricular and supraoptic hypothalamic nuclei. Besides, it was detected in neurons of other hypothalamic areas (suprachiasmatic, arcuate, and ventromedial nuclei) as well as outside the hypothalamus (Nuc. basalis Meynert, thalamus, hippocampus, and some neocortical areas). A morphometric analysis of beacon-immunoreactive hypothalamic and neocortical neurons revealed that compared to normal-weight controls in haloperidol-treated schizophrenics, there was a significant increase of protein-expressing supraoptic, paraventricular, and orbitofrontal neurons. However, a significant increase in beacon-expressing supraoptic neurons was also seen in adipose, non-psychotic individuals in comparison with normal-weight controls. Haloperidol at different doses has no effect on beacon expression in SHSY5Y neuroblastoma cells, which makes the assumption unlikely that haloperidol per se is responsible for the increased neuronal expression of the peptide in schizophrenics. In rats with a neonatal lesion of the ventral hippocampus (a widely used animal model of schizophrenia), we found an increased neuronal expression of beacon in the paraventricular and supraoptic nuclei. We suppose that elevated hypothalamic expression of beacon-like protein in non-obese schizophrenics is not primarily related to metabolic alterations, but to a certain role in schizophrenia, which is possibly unrelated to aspects of weight gain and obesity. The latter assumption finds some support by data obtained in rats with ventral hippocampus lesion.


Assuntos
Antipsicóticos/uso terapêutico , Proteínas do Olho/metabolismo , Haloperidol/uso terapêutico , Hipotálamo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/biossíntese , Esquizofrenia/metabolismo , Ubiquitinas/metabolismo , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Linhagem Celular Tumoral , Proteínas do Olho/imunologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/metabolismo , Proteínas do Tecido Nervoso/imunologia , Neurônios/metabolismo , Obesidade/complicações , Obesidade/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Escalas de Graduação Psiquiátrica , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esquizofrenia/tratamento farmacológico , Núcleo Supraóptico/metabolismo , Ubiquitinas/imunologia
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