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1.
Nat Mater ; 22(2): 194-199, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36482206

RESUMO

Mesoscopic Josephson junctions, consisting of overlapping superconducting electrodes separated by a nanometre-thin oxide layer, provide a precious source of nonlinearity for superconducting quantum circuits. Here we show that in a fluxonium qubit, the role of the Josephson junction can also be played by a lithographically defined, self-structured granular aluminium nanojunction: a superconductor-insulator-superconductor Josephson junction obtained in a single-layer, zero-angle evaporation. The measured spectrum of the resulting qubit, which we nickname gralmonium, is indistinguishable from that of a standard fluxonium. Remarkably, the lack of a mesoscopic parallel plate capacitor gives rise to an intrinsically large granular aluminium nanojunction charging energy in the range of tens of gigahertz, comparable to its Josephson energy. We measure coherence times in the microsecond range and we observe spontaneous jumps of the value of the Josephson energy on timescales from milliseconds to days, which offers a powerful diagnostics tool for microscopic defects in superconducting materials.

2.
Org Biomol Chem ; 20(17): 3598-3604, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35420107

RESUMO

Herein we report the development of a sequential synthesis route towards annulated imidazo[4,5-c]isoquinolines comprising a GBB-3CR, followed by an intramolecular imidoylative cyclisation. X-Ray crystallography revealed a flat 3D structure of the obtained polyheterocycles. Thus, we evaluated their interactions with double-stranded DNA by establishing a pUC-19 plasmid-based gel electrophoresis mobility shift assay, revealing a stabilising effect on ds-DNA against strand-break inducing conditions.


Assuntos
DNA , Isoquinolinas , Ciclização , Eletroforese em Gel de Poliacrilamida , Ensaio de Desvio de Mobilidade Eletroforética , Isoquinolinas/química , Plasmídeos
3.
Br J Surg ; 108(3): 277-285, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33793734

RESUMO

BACKGROUND: The effect of immediate total-body CT (iTBCT) on health economic aspects in patients with severe trauma is an underreported issue. This study determined the cost-effectiveness of iTBCT compared with conventional radiological imaging with selective CT (standard work-up (STWU)) during the initial trauma evaluation. METHODS: In this multicentre RCT, adult patients with a high suspicion of severe injury were randomized in-hospital to iTBCT or STWU. Hospital healthcare costs were determined for the first 6 months after the injury. The probability of iTBCT being cost-effective was calculated for various levels of willingness-to-pay per extra patient alive. RESULTS: A total of 928 Dutch patients with complete clinical follow-up were included. Mean costs of hospital care were €25 809 (95 per cent bias-corrected and accelerated (bca) c.i. €22 617 to €29 137) for the iTBCT group and €26 155 (€23 050 to €29 344) for the STWU group, a difference per patient in favour of iTBCT of €346 (€4987 to €4328) (P = 0.876). Proportions of patients alive at 6 months were not different. The proportion of patients alive without serious morbidity was 61.6 per cent in the iTBCT group versus 66.7 per cent in the STWU group (difference -5.1 per cent; P = 0.104). The probability of iTBCT being cost-effective in keeping patients alive remained below 0.56 for the whole group, but was higher in patients with multiple trauma (0.8-0.9) and in those with traumatic brain injury (more than 0.9). CONCLUSION: Economically, from a hospital healthcare provider perspective, iTBCT should be the diagnostic strategy of first choice in patients with multiple trauma or traumatic brain injury.


Assuntos
Traumatismo Múltiplo/diagnóstico por imagem , Traumatismo Múltiplo/economia , Tomografia Computadorizada por Raios X/economia , Imagem Corporal Total/economia , Adulto , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/economia , Lesões Encefálicas Traumáticas/mortalidade , Análise Custo-Benefício , Feminino , Custos Hospitalares , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Traumatismo Múltiplo/mortalidade , Países Baixos/epidemiologia , Radiografia/economia , Suíça/epidemiologia
4.
Eur Radiol ; 27(6): 2451-2462, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27709280

RESUMO

OBJECTIVES: To determine whether there is a difference in frequency and clinical relevance of incidental findings detected by total-body computed tomography scanning (TBCT) compared to those by the standard work-up (STWU) with selective computed tomography (CT) scanning. METHODS: Trauma patients from five trauma centres were randomized between April 2011 and January 2014 to TBCT imaging or STWU consisting of conventional imaging with selective CT scanning. Incidental findings were divided into three categories: 1) major finding, may cause mortality; 2) moderate finding, may cause morbidity; and 3) minor finding, hardly relevant. Generalized estimating equations were applied to assess differences in incidental findings. RESULTS: In total, 1083 patients were enrolled, of which 541 patients (49.9 %) were randomized for TBCT and 542 patients (50.1 %) for STWU. Major findings were detected in 23 patients (4.3 %) in the TBCT group compared to 9 patients (1.7 %) in the STWU group (adjusted rate ratio 2.851; 95%CI 1.337-6.077; p < 0.007). Findings of moderate relevance were detected in 120 patients (22.2 %) in the TBCT group compared to 86 patients (15.9 %) in the STWU group (adjusted rate ratio 1.421; 95%CI 1.088-1.854; p < 0.010). CONCLUSIONS: Compared to selective CT scanning, more patients with clinically relevant incidental findings can be expected by TBCT scanning. KEY POINTS: • Total-body CT scanning in trauma results in 1.5 times more incidental findings. • Evaluation by TBCT in trauma results in more patients with incidental findings. • In every category of clinical relevance, TBCT detects more incidental findings.


Assuntos
Ferimentos e Lesões/diagnóstico por imagem , Adulto , Feminino , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Encaminhamento e Consulta , Tomografia Computadorizada por Raios X/métodos , Centros de Traumatologia , Imagem Corporal Total/métodos
5.
Clin Radiol ; 71(6): 615.e1-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27005016

RESUMO

AIM: To assess image quality and radiation dose in patients with body weights ≤75 kg undergoing abdominal computed tomography (CT) with a tube voltage of either 120 or 100 kVp. MATERIALS AND METHODS: Eighty patients weighing ≤75 kg were prospectively assigned to receive either 120 or 100 kVp abdominal CT in the portal-venous phase. Attenuation values of abdominal organs and image noise were measured, and the contrast-to-noise ratios (CNRs) were calculated. Subjective image quality was assessed by three independent radiologists. Radiation exposure was assessed by size-specific dose estimate (SSDE). RESULTS: The mean attenuation of the kidney increased by 20% at 100 kVp (p<0.0001), and the mean image noise was 27% higher in the 100 kVp (p=0.003). The CNR did not significantly differ between the groups (120 kVp, 6.6±2.8; 100 kVp, 7.4±3.6; p=0.26). Except for subjective image noise (p<0.001), no other subjective quality parameters (e.g., contrast, artefacts) were significantly different between the two groups (p between 0.094 and 0.761). The mean SSDE in the 100-kVp group (9.8±1.8 mGy) was reduced by 19% compared to the 120-kVp group (12.1±1.8 mGy; p<0.0001). CONCLUSION: Manual reduction of tube voltage from the standard 120 to 100 kVp for portal-venous phase CT in patients with body weights ≤75 kg resulted in a 19% dose reduction while maintaining objective and subjective image quality.


Assuntos
Peso Corporal , Tomografia Computadorizada Multidetectores/métodos , Doses de Radiação , Proteção Radiológica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Abdominal/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiometria/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Lett Appl Microbiol ; 62(6): 437-43, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27100065

RESUMO

UNLABELLED: This study aimed to screen the antibacterial activity of 160 extracts of 40 mushroom species, collected in Hungary, against 11 standard bacterial strains and 9 clinical isolates. The further objective of this work was to evaluate the capacity of active fungal extracts to potentiate the action of antibiotics against resistant pathogens. Disc-diffusion method was applied for screening of antibacterial activity of extracts. Microdilution method was used to determine minimum inhibitory concentrations. The active extracts were applied to different resistant micro-organisms (multiresistant Acinetobacter baumannii and Pseudomonas aeruginosa, vancomycin-resistant Enterococcus faecium and MRSA), combined with commercial drugs. The synergism between extracts and antibiotics was assessed by double-disc synergy assay and determination of fractional inhibitory concentration (FIC) with checkerboard technique. From 40 mushrooms included in this experiment, 16 species exhibited antibacterial effects with moderate to high potential. In general the chloroform extracts proved to be most active, while the aqueous and aqueous-methanolic extracts demonstrated low or no activity. Fistulina hepatica, Tapinella atrotomentosa (syn. Paxillus atrotomentosus) and Rhodocybe popinalis were the most active species; moreover, they can potentiate the action of cefuroxime against MRSA. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, 160 organic (n-hexane, chloroform and 50% methanol) and aqueous extracts of 40 mushroom species were submitted to antibacterial screening assay. The antibacterial capacity of 18 species has been examined for the first time. Nineteen extracts of 16 species showed antibacterial effects with moderate to high potential. The extracts of Fistulina hepatica, Tapinella atrotomentosa and Rhodocybe popinalis exhibited not only broad antibacterial spectrum, but also synergistic activity with cefuroxime against MRSA. Our screening study proved that mushroom species are promising sources of potential antimicrobial molecules. The results serve as good starting point for selection of fungal species for detailed pharmacological and chemical investigation.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Agaricales/química , Antibacterianos/farmacologia , Extratos Celulares/farmacologia , Enterococcus faecium/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Cefuroxima/farmacologia , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Enterococcus faecium/crescimento & desenvolvimento , Humanos , Hungria , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana/métodos , Pseudomonas aeruginosa/crescimento & desenvolvimento
7.
Mol Psychiatry ; 19(4): 478-85, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23528911

RESUMO

The underlying pathology of schizophrenia (SZ) is likely as heterogeneous as its symptomatology. A variety of cortical and subcortical regions, including the prefrontal cortex, have been implicated in its pathology, and a number of genes have been identified as risk factors for disease development. We used in situ hybridization (ISH) to examine the expression of 58 genes in the dorsolateral prefrontal cortex (DLPFC, comprised of Brodmann areas 9 and 46) from 19 individuals with a premorbid diagnosis of SZ and 33 control individuals. Genes were selected based on: (1) previous identification as risk factors for SZ; (2) cell type markers or (3) laminar markers. Cell density and staining intensity were compared in the DLPFC, as well as separately in Brodmann areas 9 and 46. The expression patterns of a variety of genes, many of which are associated with the GABAergic system, were altered in SZ when compared with controls. Additional genes, including C8orf79 and NR4A2, showed alterations in cell density or staining intensity between the groups, highlighting the need for additional studies. Alterations were, with only a few exceptions, limited to Brodmann area 9, suggesting regional specificity of pathology in the DLPFC. Our results agree with previous studies on the GABAergic involvement in SZ, and suggest that areas 9 and 46 may be differentially affected in the disease. This study also highlights additional genes that may be altered in SZ, and indicates that these potentially interesting genes can be identified by ISH and high-throughput image analysis techniques.


Assuntos
Regulação da Expressão Gênica/fisiologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/patologia , Adulto , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/metabolismo , Neuroimagem , Neurônios/metabolismo , Córtex Pré-Frontal/patologia , Esquizofrenia/genética , Adulto Jovem
8.
Pharmazie ; 68(1): 15-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23444775

RESUMO

Adulteration of botanical food supplements with undeclared synthetic drugs is a common problem. One of the most affected product groups are the slimming agents. There are no analytical protocols for the detection of synthetic adulterants from these products. The present study aimed at the development of a multistep analytical method for the quick and reliable determination of sibutramine, one of the most common adulterants among botanical food supplements. The extract of a sibutramine-containing slimming formula was analysed by colour tests, TLC, HPLC-DAD, MS and NMR. The multistep method proposed by the authors allows the quick identification of sibutramine in counterfeit samples in laboratories with different instrumentation.


Assuntos
Depressores do Apetite/análise , Ciclobutanos/análise , Suplementos Nutricionais/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Cor , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
10.
Phytother Res ; 24(11): 1605-13, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21031616

RESUMO

Echinacea preparations are traditionally used to treat upper respiratory infections and inflammations. No psychotropic effects of Echinacea have been reported so far, although some recently reported active constituents are behaviorally active. Prompted by these findings, the anxiolytic potential of five different Echinacea preparations was evaluated. Three of these decreased anxiety but two of them had a very narrow effective dose range. Only one extract decreased anxiety within a wide dose-range (3-8 mg/kg). Anxiolytic effects were consistently seen in three different tests of anxiety, the elevated plus-maze, social interaction and shock-induced social avoidance tests. No locomotor suppressant effects were seen at any dose. Noteworthy, the doses that showed anxiolytic effects in the present study were much lower than those used in the laboratory models of the traditional indications. Chlordiazepoxide robustly decreased anxiety-like behavior in all tests but suppressed locomotion at higher doses. Perceived and real risks of conventional medications increase the demand for alternative therapies, provided that these are safe and efficient. Earlier evidence shows that Echinacea preparations have an excellent safety profile, while our findings suggest for the first time that certain preparations have a considerable anxiolytic potential. Further research is required to identify factors that differentiate efficient and inefficient preparations.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Clordiazepóxido/farmacologia , Echinacea/química , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Fitoterapia , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Comportamento Social
11.
Anaesth Rep ; 8(2): e12055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32705085

RESUMO

Spurred in part by literature published in the immediate aftermath of the severe acute respiratory syndrome epidemic in 2003, powered air-purifying respirators have seen increased use worldwide during the COVID-19 pandemic. Whereas these devices provide excellent protection of the user, there is an added element of risk during doffing and cleaning of the device. An additional layer of barrier protection, in the form of a polypropylene gown, to be worn over the hood and motor belt, can be used to minimise this risk. However, the device entrains air perpendicular to the lie of the gown, resulting in the impermeable material being sucked into the air intake, and partial occlusion of flow. In this report, we describe a clinical-academic partnership whereby a bespoke filter guard was designed to disrupt airflow and prevent gown entrainment, thereby enabling full barrier protection of both the device and user. This intervention was simple, cheap, scalable and able to be mass produced.

12.
Ultraschall Med ; 30(2): 185-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18726842

RESUMO

A 49 year old male with carcinoma of the esophagus was staged using conventional US of the abdomen. US revealed signs of cirrhosis and a hyporeflexive focal liver lesion of about 5 mm in diameter was found. Low-MI contrast-enhanced ultrasound (CEUS) with SonoVue (Bracco, Milano, Italy) showed an enhancement pattern which was typical for benign liver lesions while high-MI CEUS with Levovist (Schering, Berlin, Germany) revealed a contrast defect in the liver late phase (4:30 min p. i.) which is typical for a malignant lesion. Due to these findings the lesion was evaluated as a potentially malignant lesion and a biopsy was performed. Histology showed a benign biliary hamartoma and incomplete cirrhosis. The findings confirmed that liver-specific contrast agents have the ability to detect very small focal liver lesions not derived from hepatic tissue but may lead to a misinterpretation as a malignant lesion. Nevertheless biliary duct adenomas are benign lesions with almost the same perfusion properties as normal liver parenchyma. Therefore, while using SonoVue, such a misinterpretation of these very common but in most cases very small and not detectable lesions seems unlikely.


Assuntos
Adenoma de Ducto Biliar/diagnóstico por imagem , Doenças dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Meios de Contraste , Hamartoma/diagnóstico por imagem , Fosfolipídeos , Polissacarídeos , Hexafluoreto de Enxofre , Ultrassonografia Doppler Dupla , Adenoma de Ducto Biliar/patologia , Doenças dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Biópsia por Agulha Fina , Diagnóstico Diferencial , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Humanos , Achados Incidentais , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Sensibilidade e Especificidade
13.
Mol Cell Biol ; 24(7): 2978-85, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15024085

RESUMO

Neuropeptide Y (NPY) and galanin have both been implicated in the regulation of body weight, yet mice bearing deletions of either of these molecules have unremarkable metabolic phenotypes. To investigate whether galanin and NPY might compensate for one another, we produced mutants lacking both neuropeptides (GAL(-/-)/NPY(-/-)). We found that male GAL(-/-)/NPY(-/-) mice ate significantly more and were much heavier (30%) than wild-type (WT) controls. GAL(-/-)/NPY(-/-) mice responded to a high-fat diet by gaining more weight than WT mice gain, and they were unable to regulate their weight normally after a change in diet. GAL(-/-)/NPY(-/-) mice had elevated levels of leptin, insulin, and glucose, and they lost more weight than WT mice during chronic leptin treatment. Galanin mRNA was increased in the hypothalamus of NPY(-/-) mice, providing evidence of compensatory regulation in single mutants. The disruption of energy balance observed in GAL(-/-)/NPY(-/-) double knockouts is not found in the phenotype of single knockouts of either molecule. The unexpected obesity phenotype may result from the dysregulation of the leptin and insulin systems that normally keep body weight within the homeostatic range.


Assuntos
Sistema Endócrino/fisiopatologia , Galanina/metabolismo , Neuropeptídeo Y/metabolismo , Obesidade/genética , Obesidade/metabolismo , Animais , Peso Corporal , Ritmo Circadiano , Gorduras na Dieta , Núcleo Hipotalâmico Dorsomedial/citologia , Núcleo Hipotalâmico Dorsomedial/metabolismo , Ingestão de Alimentos , Galanina/genética , Hormônios/sangue , Insulina/metabolismo , Leptina/administração & dosagem , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Atividade Motora/fisiologia , Neuropeptídeo Y/genética , Fenótipo
14.
Hamostaseologie ; 36(1): 17-25, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26328528

RESUMO

UNLABELLED: Antiplatelet therapy is given to millions of patients and has saved numerous lives. However, it is also associated with complications including fatal bleedings. Clinically used antiplatelet drugs seem to follow the rule of an inherent link of improved anti-thrombotic potency with increased risk of bleeding complications. Therefore, there is an ongoing quest to develop drugs that are able to break this link that has prevented many patients from receiving antiplatelet protection and has resulted in substantial mortality and morbidity. We describe a new antiplatelet approach that is based on an recombinant antibody protein, a drug format that has recently attracted major interest. Two unique components are genetically combined in this molecule: 1) The ecto-nucleoside triphosphate diphosphohydrolase NTPDase CD39, which enzymatically degrades ATP and ADP to AMP, which is then further degraded to adenosine by the endothelially expressed CD73. Thereby, the platelet activating ADP is reduced and replaced by the platelet inhibiting adenosine resulting in a strong antiplatelet effect. 2) A single-chain antibody (scFv) that specifically binds to the activated GPIIb/IIIa receptor and thus allows targeting to activated platelets. The described fusion protein results in strong enrichment of CD39's antiplatelet effect, resulting in potent inhibition of platelet adhesion and aggregation and thrombosis in mice. The activated platelet targeting allows using a low systemic concentration that does not interfere with normal haemostasis and thus does not cause bleeding time prolongation in mice. CONCLUSION: We describe a new antiplatelet approach that promises to deliver strong localized antithrombotic effects without associated bleeding problems.


Assuntos
Antígenos CD/imunologia , Apirase/imunologia , Terapia de Alvo Molecular/métodos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/imunologia , Trombose/tratamento farmacológico , Trombose/imunologia , Animais , Desenho de Fármacos , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Humanos , Camundongos , Inibidores da Agregação Plaquetária/efeitos adversos , Ratos , Resultado do Tratamento
15.
J Neurosci ; 21(19): 7764-9, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11567066

RESUMO

Epilepsy is a disease of neuronal hyperexcitability, and pharmacological and genetic studies have identified norepinephrine (NE) and neuropeptide Y (NPY) as important endogenous regulators of neuronal excitability. Both transmitters signal through G-protein-coupled receptors, are expressed either together or separately, and are abundant in brain regions implicated in seizure generation. NPY knock-out (NPY KO) and dopamine beta-hydroxylase knock-out (DBH KO) mice that lack NE are susceptible to seizures, and agonists of NE and NPY receptors protect against seizures. To examine the relative contributions of NE and NPY to neuronal excitability, we tested Dbh;Npy double knock-out (DKO) mice for seizure sensitivity. In general, DBH KO mice were much more seizure-sensitive than NPY KO mice and had normal NPY expression, demonstrating that an NPY deficiency did not contribute to the DBH KO seizure phenotype. DKO mice were only slightly more sensitive than DBH KO mice to seizures induced by kainic acid, pentylenetetrazole, or flurothyl, although DKO mice were uniquely prone to handling-induced seizures. NPY contributed to the seizure phenotype of DKO mice at high doses of convulsant agents and advanced stages of seizures. These data suggest that NE is a more potent endogenous anticonvulsant than NPY, and that NPY has the greatest contribution under conditions of extreme neuronal excitability.


Assuntos
Predisposição Genética para Doença , Neuropeptídeo Y/metabolismo , Norepinefrina/metabolismo , Convulsões/fisiopatologia , Animais , Dopamina beta-Hidroxilase/deficiência , Dopamina beta-Hidroxilase/genética , Teste de Esforço , Flurotila , Manobra Psicológica , Hibridização In Situ , Ácido Caínico , Masculino , Camundongos , Camundongos Knockout , Neuropeptídeo Y/deficiência , Neuropeptídeo Y/farmacologia , Norepinefrina/deficiência , Norepinefrina/farmacologia , Pentilenotetrazol , Fenótipo , Convulsões/induzido quimicamente , Convulsões/prevenção & controle
16.
Biochim Biophys Acta ; 1152(1): 146-54, 1993 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-8399292

RESUMO

An ATPase was isolated from synaptosomal plasma membranes derived from bovine cerebral cortex. The protein has an apparent molecular mass of 50 kDa and a pI of 5.3 to 5.9. It can be labelled by incubation of intact synaptosomes with azido-GTP or azido-ATP. The isolated ATPase can be activated to a similar extent in the presence of millimolar concentrations of Mg2+ or Ca2+. It does not hydrolyze ADP. Maximal activity is obtained between pH 7.5 and 8.5. Typical inhibitors of cytoplasmic ATPases do not affect enzyme activity. The enzyme is specifically inhibited after previous incubation of intact synaptosomes in the presence of the slowly membrane-permeable enzyme inhibitor diazotized sulfanilic acid. Incubation of intact synaptosomes with diazotized sulfanilic acid results in a small increase in the apparent molecular mass of the enzyme. Our results suggest that the active site of the membrane bound enzyme faces the extracellular medium. It thus would represent an ecto-ATPase.


Assuntos
Adenosina Trifosfatases/isolamento & purificação , Encéfalo/enzimologia , ATPase de Ca(2+) e Mg(2+)/isolamento & purificação , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/imunologia , Trifosfato de Adenosina/análogos & derivados , Marcadores de Afinidade , Animais , Azidas , ATPase de Ca(2+) e Mg(2+)/antagonistas & inibidores , ATPase de Ca(2+) e Mg(2+)/química , Bovinos , Compostos de Diazônio/farmacologia , Guanosina Trifosfato/análogos & derivados , Concentração de Íons de Hidrogênio , Especificidade por Substrato , Ácidos Sulfanílicos/farmacologia , Membranas Sinápticas/enzimologia , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/enzimologia
17.
Neuroscience ; 133(2): 371-80, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15885921

RESUMO

The functional interactions of the neuropeptide galanin (GAL) occur through its binding to three G protein-coupled receptor subtypes: galanin receptor (GALR) 1, GALR2 and GALR3. Previously, we demonstrated that GALR1 mRNA expression was increased in the CA1 region of the hippocampus and discrete hypothalamic nuclei in galanin transgenic (GAL-tg) mice. This observation suggested a compensatory adjustment in cognate receptors in the face of chronic GAL exposure. To evaluate the molecular alterations to GALR2 and GALR3 in the forebrain of GAL overexpressing mice, we performed complementary quantitative, real-time PCR (qPCR), in situ hybridization, and immunohistochemistry in select forebrain regions of GAL-tg mice to characterize the neuronal distribution and magnitude of GAL mRNA and peptide expression and the consequences of genetically manipulating the neuropeptide GAL on the expression of GALR2 and GALR3 receptors. We found that GAL-tg mice displayed dramatic increases in GAL mRNA and peptide in the frontal cortex, posterior cortex, hippocampus, septal diagonal band complex, amygdala, piriform cortex, and olfactory bulb. Moreover, there was evidence for ectopic neuronal GAL expression in forebrain limbic regions that mediate cognitive and affective behaviors, including the piriform and entorhinal cortex and amygdala. Interestingly, regional qPCR analysis failed to reveal any changes in GALR2 or GALR3 expression in the GAL-tg mice, suggesting that, contrary to GALR1, these receptor genes are not under ligand-mediated regulatory control. The GAL-tg mouse model may provide a useful tool for the investigation of GAL ligand-receptor relationships and their role in normal cognitive and affective functions as well as in the onset of neurological disease.


Assuntos
Galanina/metabolismo , Regulação da Expressão Gênica/genética , Prosencéfalo/metabolismo , Receptor Tipo 2 de Galanina/metabolismo , Receptor Tipo 3 de Galanina/metabolismo , Animais , Galanina/genética , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Prosencéfalo/anatomia & histologia , RNA Mensageiro/metabolismo , Receptor Tipo 2 de Galanina/genética , Receptor Tipo 3 de Galanina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
18.
In Vivo ; 19(2): 367-74, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15796199

RESUMO

The drug accumulation of a human multidrug resistance 1 (mdr1) gene-transfected mouse lymphoma cell line and a multidrug resistance protein (MRP)-expressing human breast cancer cell line MDA-MB-231 was compared in the presence of sixteen flavonoids and five isoflavonoids. The expression of the 170-kDa P-glycoprotein (P-gp) (MDR1) and 190-kDa multidrug resistance protein (MRP) in both cell lines was confirmed by immunocytochemistry. The rhodamine 123 accumulation of the P-glycoprotein (P-gp)-expressing cells increased up to 46.4, while 2,7'-bis(2-carboxyethyl)-5(6)-carboxy-fluorescein acetoxymethyl ester (BCECF-AM) accumulation of the MRP-expressing cells increased up to 1.6, in fluorescence activity ratio (FAR). Major P-gp-mediated efflux pump modifiers are formononetin, amorphigenin, rotenone and chrysin, while MRP-mediated efflux pump modifiers are formononetin, afrormosin, robinin, kaempferol and epigallocatechin. In antiproliferative assay, afrormosin, amorphigenin, chrysin and rotenone exhibited the strongest antiproliferative effects in L5178 (max. ID50: 19.70) and MDA-MB-231 cell lines (max. ID50: 55.47). In a checkerboard microplate method in vitro, furthermore, the most effective multidrug resistance (MDR) resistance modifiers, amorphigenin, formononetin, rotenone and chrysin, were assayed for their antiproliferative effects in combination with epirubicin. Rotenone and afrormosin showed additive effects. Chrysin and amorphigenin on the mouse lymphoma cell line and formononetin on the MDA-MB-231 cell line synergistically enhanced the effect of epirubicin.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos , Epirubicina/farmacologia , Flavonoides/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Humanos , Isoflavonas/farmacologia , Camundongos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
Rofo ; 187(6): 467-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25877993

RESUMO

PURPOSE: The aim of the study was to evaluate whether or not MRCP using a 3D-SPACE sequence allows for better image quality and a higher level of diagnostic confidence than a conventional 3D-TSE sequence at 1.5 T regarding the diagnosis of choledocholithiasis in a routine clinical setting. MATERIALS AND METHODS: 3D-SPACE and 3D-TSE sequences were performed in 42 consecutive patients with suspected choledocholithiasis undergoing MRCP. Evaluation of image quality and diagnostic confidence was done on the pancreaticobiliary tree which was subdivided into 10 segments. They were scored and statistically evaluated separately for visibility and diagnostic certainty by three radiologists with differing levels of experience on a five-point scale of 1 to 5 and -2 to 2, respectively. Student t-test was performed, and the interobserver agreement was also calculated. RESULTS: Image quality for each segment was significantly better for the 3D-SPACE sequence compared to the 3D-TSE sequence (4.48 ±â€Š0.94 vs. 3.98 ±â€Š1.20; 5-point scale p < 0.01). Diagnostic confidence for the reporting radiologist was also significantly better for 3D-SPACE than for 3D-TSE (1.68 ±â€Š0.56 vs. 1.46 ±â€Š0.70; 3-point scale; p < 0.01). The interobserver agreement was high in both sequences, 0.62 - 0.83 and 0.64 - 0.82, respectively. CONCLUSION: The optimized 3D-SPACE sequence allows for better image quality in 1.5 T MRCP examinations and leads to a higher diagnostic confidence for choledocholithiasis compared to the conventional 3D-TSE sequence. KEY POINTS: • 3D-SPACE allows for better image quality in 1.5 T MRCP.• This leads to a higher diagnostic confidence particularly in the periampullary region.• 3D-SPACE should be considered to substitute conventional 3D-TSE sequences in clinical routine MRCP.


Assuntos
Colangiopancreatografia por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Coledocolitíase , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador
20.
Neuroscience ; 103(2): 423-32, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11246157

RESUMO

Galanin is widely distributed throughout the mammalian brain and has been implicated in the regulation of food intake, metabolism and reproduction-functions that are also thought to be under the control of leptin. To investigate the possible role of galanin in mediating the physiological effects of leptin in the mouse, we had three experimental objectives: first, to map the distribution of galanin messenger RNA-expressing cells in the brain of the mouse; second, to assess the effects of leptin on galanin gene expression in areas of the brain thought to be involved in the regulation of body weight and reproduction; and third, to determine whether galanin neurons in these regions express leptin receptor messenger RNA. We found the pattern of galanin messenger RNA expression in the mouse brain to be similar, but not identical, to that in the rat. Leptin treatment (2microg/g for six days) significantly reduced cellular levels of galanin messenger RNA in the hypothalamic periventricular nucleus of leptin-deficient obese (ob/ob) mice (P<0.01) by approximately 30%; however, leptin did not appear to influence the expression of galanin in the arcuate or dorsomedial nucleus of the hypothalamus. Galanin-producing neurons in the arcuate, dorsomedial and periventricular nuclei did not appear to express leptin receptor messenger RNA (P>0.05). These results demonstrate that galanin distribution patterns in the mouse brain are comparable to other species and, yet, possess unique features. In addition, galanin-expressing neurons in the hypothalamic periventricular nucleus are targets for regulation by leptin; however, the effect of leptin on galanin gene expression is likely to be mediated indirectly, perhaps through either proopiomelanocortin- or neuropeptide Y-expressing cells in the hypothalamus.


Assuntos
Galanina/genética , Regulação da Expressão Gênica/fisiologia , Leptina/genética , Leptina/farmacologia , Núcleo Hipotalâmico Paraventricular/fisiologia , Receptores de Superfície Celular , Animais , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Núcleo Arqueado do Hipotálamo/fisiologia , Química Encefálica/genética , Proteínas de Transporte/fisiologia , Núcleo Hipotalâmico Dorsomedial/efeitos dos fármacos , Núcleo Hipotalâmico Dorsomedial/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/genética , Obesidade/fisiopatologia , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , RNA Mensageiro/análise , Receptores para Leptina
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