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1.
Sci Rep ; 6: 35772, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27808109

RESUMO

We derive structural and binding energy trends for twenty amino acids, their dipeptides, and their interactions with the divalent cations Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+. The underlying data set consists of more than 45,000 first-principles predicted conformers with relative energies up to ~4 eV (~400 kJ/mol). We show that only very few distinct backbone structures of isolated amino acids and their dipeptides emerge as lowest-energy conformers. The isolated amino acids predominantly adopt structures that involve an acidic proton shared between the carboxy and amino function. Dipeptides adopt one of two intramolecular-hydrogen bonded conformations C5 or . Upon complexation with a divalent cation, the accessible conformational space shrinks and intramolecular hydrogen bonding is prevented due to strong electrostatic interaction of backbone and side chain functional groups with cations. Clear correlations emerge from the binding energies of the six divalent ions with amino acids and dipeptides. Cd2+ and Hg2+ show the largest binding energies-a potential correlation with their known high acute toxicities. Ca2+ and Pb2+ reveal almost identical binding energies across the entire series of amino acids and dipeptides. This observation validates past indications that ion-mimicry of calcium and lead should play an important role in a toxicological context.


Assuntos
Aminoácidos/química , Aminoácidos/metabolismo , Cálcio/metabolismo , Dipeptídeos/química , Dipeptídeos/metabolismo , Chumbo/metabolismo , Cálcio/química , Humanos , Chumbo/química , Modelos Moleculares , Conformação Proteica , Termodinâmica
2.
Chem Commun (Camb) ; 52(83): 12353-12356, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27711324

RESUMO

There has been increasing evidence that certain isomeric glycans can be separated efficiently by ion mobility-mass spectrometry when deprotonated ions are analyzed. To better understand the fundamentals behind these separations, we here investigate the impact of ionisation mode and adduct formation using IM-MS, density-functional theory and ab initio molecular dynamics.

3.
Genet Mol Res ; 13(3): 5138-42, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25061738

RESUMO

The Atlantic rainforest species Ocotea catharinensis, Ocotea odorifera, and Ocotea porosa have been extensively harvested in the past for timber and oil extraction and are currently listed as threatened due to overexploitation. To investigate the genetic diversity and population structure of these species, we developed 8 polymorphic microsatellite markers for O. odorifera from an enriched microsatellite library by using 2 dinucleotide repeats. The microsatellite markers were tested for cross-amplification in O. catharinensis and O. porosa. The average number of alleles per locus was 10.2, considering all loci over 2 populations of O. odorifera. Observed and expected heterozygosities for O. odorifera ranged from 0.39 to 0.93 and 0.41 to 0.92 across populations, respectively. Cross-amplification of all loci was successfully observed in O. catharinensis and O. porosa except 1 locus that was found to lack polymorphism in O. porosa. Combined probabilities of identity in the studied Ocotea species were very low ranging from 1.0 x 10-24 to 7.7 x 10-24. The probability of exclusion over all loci estimated for O. odorifera indicated a 99.9% chance of correctly excluding a random nonparent individual. The microsatellite markers described in this study have high information content and will be useful for further investigations on genetic diversity within these species and for subsequent conservation purposes.


Assuntos
Espécies em Perigo de Extinção , Loci Gênicos , Repetições de Microssatélites , Ocotea/genética , Alelos , Conservação dos Recursos Naturais , Marcadores Genéticos , Variação Genética , Genética Populacional , Heterozigoto , Ocotea/classificação , Floresta Úmida , Especificidade da Espécie
4.
Thromb Haemost ; 112(1): 96-108, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-24598842

RESUMO

The bleeding disorder von Willebrand disease (VWD) is caused by mutations of von Willebrand factor (VWF), a multimeric glycoprotein essential for platelet-dependent primary haemostasis. VWD type 2A-associated mutations each disrupt VWF biosynthesis and function at different stages, depending on the VWF domain altered by the mutation. These effects cause considerable heterogeneity in phenotypes and symptoms. To characterise the molecular mechanisms underlying the specific VWF deficiencies in VWD 2A/IIC, IID and IIE, we investigated VWF variants with patient-derived mutations either in the VWF pro-peptide or in domains D3 or CK. Additionally to static assays and molecular dynamics (MD) simulations we used microfluidic approaches to perform a detailed investigation of the shear-dependent function of VWD 2A mutants. For each group, we found distinct characteristics in their intracellular localisation visualising specific defects in biosynthesis which are correlated to respective multimer patterns. Using microfluidic assays we further determined shear flow-dependent characteristics in polymer-platelet-aggregate formation, platelet binding and string formation for all mutants. The phenotypes observed under flow conditions were not related to the mutated VWF domain. By MD simulations we further investigated how VWD 2A/IID mutations might alter the ability of VWF to form carboxy-terminal dimers. In conclusion, our study offers a comprehensive picture of shear-dependent and shear-independent dysfunction of VWD type 2A mutants. Furthermore, our microfluidic assay might open new possibilities for diagnosis of new VWD phenotypes and treatment choice for VWD patients with shear-dependent VWF dysfunctions that are currently not detectable by static tests.


Assuntos
Plaquetas/fisiologia , Doença de von Willebrand Tipo 2/genética , Fator de von Willebrand/metabolismo , Dimerização , Células HEK293 , Humanos , Microfluídica , Simulação de Dinâmica Molecular , Mutação/genética , Fenótipo , Estrutura Terciária de Proteína/genética , Resistência ao Cisalhamento/fisiologia , Doença de von Willebrand Tipo 2/classificação , Fator de von Willebrand/genética
5.
Calcif Tissue Int ; 94(5): 474-83, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24366459

RESUMO

That phosphate homeostasis is tightly linked to skeletal mineralization is probably best underscored by the fact that the phosphaturic hormone FGF23 is primarily expressed by terminally differentiated osteoblasts/osteocytes and that increased circulating FGF23 levels are causative for different types of hypophosphatemic rickets. In contrast, FGF23 inactivation results in hyperphosphatemia, and unexpectedly this phenotype is associated with severe osteomalacia in Fgf23-deficient mice. In this context it is interesting that different cell types have been shown to respond to extracellular phosphate, thereby raising the concept that phosphate can act as a signaling molecule. To identify phosphate-responsive genes in primary murine osteoblasts we performed genome wide expression analysis with cells maintained in medium containing either 1 or 4 mM sodium phosphate for 6 h. As confirmed by qRT-PCR, this analysis revealed that several known osteoblast differentiation markers (Bglap, Ibsp, and Phex) were unaffected by raising extracellular phosphate levels. In contrast, we found that the expression of Enpp1 and Ank, two genes encoding inhibitors of matrix mineralization, was induced by extracellular phosphate, while the expression of Sost and Dkk1, two genes encoding inhibitors of bone formation, was negatively regulated. The ability of osteoblasts to respond to extracellular phosphate was dependent on their differentiation state, and shRNA-dependent repression of the phosphate transporter Slc20a1 in MC3T3-E1 cells partially abolished their molecular response to phosphate. Taken together, our results provide further evidence for a role of extracellular phosphate as a signaling molecule and raise the possibility that severe hyperphosphatemia can negatively affect skeletal mineralization.


Assuntos
Calcificação Fisiológica/fisiologia , Osteoblastos/metabolismo , Fosfatos/metabolismo , Animais , Fator de Crescimento de Fibroblastos 23 , Regulação da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real
6.
Aliment Pharmacol Ther ; 33(12): 1311-21, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21507028

RESUMO

BACKGROUND: Neurokinin receptors may play an important role in the visceral hypersensitivity and exaggerated motor/secretory activity associated with diarrhoea-predominant irritable bowel syndrome (IBS-D). AIM: To evaluate the effects of DNK333, a novel neurokinin antagonist, in women with IBS-D. METHODS: In two consecutive phase II studies, women with IBS-D were randomised to twice-daily (b.d.) DNK333 25 mg, DNK333 100 mg or placebo for 2 weeks (Trial 1), or DNK333 25 mg b.d. or placebo for 4 weeks (Trial 2). Primary efficacy variables studied were change from baseline of stool form at week 2, and satisfactory relief of IBS-related abdominal pain/discomfort and global IBS-D symptoms. Secondary efficacy variables, pharmacokinetics and safety were also evaluated. RESULTS: In total, 315 subjects were randomised. There were no statistically significant differences between treatment groups for the primary efficacy variables. However, analysis of combined data from both trials revealed significant differences favouring DNK333 25 mg over placebo for satisfactory relief of IBS-related abdominal pain/discomfort and global IBS-D symptoms. Trends favouring improvement with DNK333 25 mg vs. placebo were seen for all secondary efficacy variables. DNK333 had a safety profile similar to placebo. CONCLUSIONS: DNK333 25 mg b.d. appears to be effective and well tolerated in women with IBS-D. Further studies with neurokinin antagonists are warranted.


Assuntos
Dor Abdominal/tratamento farmacológico , Compostos Aza/uso terapêutico , Benzamidas/uso terapêutico , Diarreia/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Placebos/uso terapêutico , Receptores de Taquicininas/antagonistas & inibidores , Dor Abdominal/genética , Dor Abdominal/fisiopatologia , Adolescente , Adulto , Idoso , Diarreia/genética , Diarreia/fisiopatologia , Feminino , Humanos , Síndrome do Intestino Irritável/classificação , Síndrome do Intestino Irritável/genética , Síndrome do Intestino Irritável/fisiopatologia , Pessoa de Meia-Idade , Receptores de Taquicininas/genética , Resultado do Tratamento , Adulto Jovem
7.
J Thromb Haemost ; 7(12): 2096-105, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19817991

RESUMO

BACKGROUND: To avoid pathological platelet aggregation by von Willebrand factor (VWF), VWF multimers are regulated in size and reactivity for adhesion by ADAMTS13-mediated proteolysis in a shear flow dependent manner. OBJECTIVE AND METHODS: We examined whether tensile stress in VWF under shear flow activates the VWF A2 domain for cleavage by ADAMTS13 using molecular dynamics simulations. We generated a full length mutant VWF featuring a homologous disulfide bond in A2 (N1493C and C1670S), in an attempt to lock A2 against unfolding. RESULTS: We indeed observed stepwise unfolding of A2 and exposure of its deeply buried ADAMTS13 cleavage site. Interestingly, disulfide bonds in the adjacent and highly homologous VWF A1 and A3 domains obstruct their mechanical unfolding. We find this mutant A2 (N1493C and C1670S) to feature ADAMTS13-resistant behavior in vitro. CONCLUSIONS: Our results yield molecular-detail evidence for the force-sensing function of VWF A2, by revealing how tension in VWF due to shear flow selectively exposes the A2 proteolysis site to ADAMTS13 for cleavage while keeping the folded remainder of A2 intact and functional. We find the unconventional 'knotted' Rossmann fold of A2 to be the key to this mechanical response, tailored for regulating VWF size and activity. Based on our model we discuss the pathomechanism of some natural mutations in the VWF A2 domain that significantly increase the cleavage by ADAMTS13 without shearing or chemical denaturation, and provide with the cleavage-activated A2 conformation a structural basis for the design of inhibitors for VWF type 2 diseases.


Assuntos
Proteínas ADAM/metabolismo , Desnaturação Proteica , Estabilidade Proteica , Fator de von Willebrand/metabolismo , Proteína ADAMTS13 , Adesividade , Humanos , Hidrólise , Mutação , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Estresse Mecânico , Fator de von Willebrand/genética
8.
Gut ; 54(12): 1707-13, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16020489

RESUMO

BACKGROUND: It has been proposed that treatments for irritable bowel syndrome with constipation (IBS-C) should provide rapid symptomatic relief, be intermittent, and effective upon repeated use. AIMS: To evaluate the efficacy and safety of tegaserod on IBS symptoms, and its impact on quality of life and health economic measures. PATIENTS: Women (> or = 18 years of age) with IBS-C according to the Rome II criteria. METHODS: Prospective, double blind, placebo controlled, randomised trial. Women with IBS-C either received tegaserod 6 mg twice daily or placebo for one month. Patients with at least a partial response entered a treatment free interval. Upon symptom recurrence, tegaserod treated patients were re-randomised to tegaserod or placebo for an additional month. Primary efficacy variables were response (overall IBS symptoms and abdominal discomfort/pain) to first and repeated treatment. Analysis was by intention to treat. RESULTS: 2660 patients and 1191 patients were randomised for first and repeated treatment respectively. Tegaserod was superior to placebo for each primary efficacy variable (first treatment: 33.7% v 24.2% responders respectively for relief of IBS symptoms and 31.3% v 22.1% for relief of abdominal discomfort/pain; repeated treatment: 44.9% v 28.7%, and 42.4% v 27.1%, all p < 0.0001). Tegaserod was superior to placebo for every secondary efficacy variable (relief of abdominal discomfort/pain, bloating and constipation; stool frequency and consistency). A response to tegaserod was observed within the first treatment week. Tegaserod produced greater satisfaction, work productivity, and improved quality of life than placebo (p < 0.05). CONCLUSION: Tegaserod provides rapid and sustained relief of IBS-C symptoms both during first and repeated treatment.


Assuntos
Constipação Intestinal/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Indóis/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Adolescente , Adulto , Idoso , Constipação Intestinal/reabilitação , Método Duplo-Cego , Esquema de Medicação , Eficiência , Feminino , Fármacos Gastrointestinais/efeitos adversos , Humanos , Indóis/efeitos adversos , Síndrome do Intestino Irritável/reabilitação , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Agonistas do Receptor de Serotonina/efeitos adversos , Agonistas do Receptor de Serotonina/uso terapêutico , Resultado do Tratamento
9.
Reprod Domest Anim ; 38(2): 97-101, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12654019

RESUMO

In this study, elimination of the element zinc from spermatozoa during epididymal maturation was investigated. Testes and epididymides from 40 bulls were collected; epididymal fluid was flushed, pooled, labelled with 0.5 MBq 65Zn2+ per sample and proteins were separated on a Sephacryl S-200 HR and zinc chelate column chromatography. To follow the resorption of zinc in the epididymal epithelial lining, an autometallographic technique (AMG) was performed in tissue from caput, corpus, cauda and vas deferens. The results showed a zinc-binding protein fraction with an apparent molecular weight of 150-160 kDa, which was enriched after chelate column chromatography. Specific labelling of 65Zn was about five times higher in the caput than in the cauda epididymidis. AMG revealed no detectable zinc in the caput, but a significant increase of zinc resorption from the corpus to the cauda and vas deferens. Controls showed that the detectable zinc was located within the principal cells. In conclusion, our study proves that zinc present in the sperm flagellum starts to be mobilized in the caput epididymidis and is resorbed by the epididymal epithelium as from the corpus. This zinc elimination is a mandatory step in sperm maturation to obtain motility.


Assuntos
Epididimo/fisiologia , Maturação do Esperma/fisiologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Zinco/metabolismo , Animais , Proteínas de Transporte/análise , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Bovinos , Cromatografia em Gel , Epididimo/química , Masculino , Peso Molecular , Espermatozoides/metabolismo , Testículo/citologia , Testículo/fisiologia , Radioisótopos de Zinco
10.
Arq Neuropsiquiatr ; 59(3-B): 717-21, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11593271

RESUMO

PURPOSE: To study the seizure's outcome in patients with refractory epilepsy and normal MRI submitted to resections including the rolandic cortex. METHODS: Four adult patients were studied. All patients had motor or somatosensory simple partial seizures and normal MRI and were submitted to subdural grids' implantation with extensive coverage of the cortical convexity (1 in the non-dominant and 3 in the dominant hemisphere). RESULTS: ECoG was able to define focal areas of seizures' onset in every patient. All patients were submitted to resection of the face and tongue motor and sensitive cortex; two patients had resections including the perirolandic cortex and 2 had additional cortical removals. Three patients are seizures' free and one had a greater then 90% reduction in seizure frequency. CONCLUSION: Resections including the face and tongue rolandic cortex can be safely performed even within the dominant hemisphere.


Assuntos
Córtex Cerebral/cirurgia , Epilepsia Rolândica/cirurgia , Adulto , Córtex Cerebral/fisiopatologia , Eletrodos Implantados , Eletroencefalografia , Epilepsia Rolândica/fisiopatologia , Face , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/fisiopatologia , Córtex Motor/cirurgia , Espaço Subdural , Lobo Temporal/fisiopatologia , Lobo Temporal/cirurgia , Língua , Resultado do Tratamento
11.
Epilepsia ; 42(7): 889-94, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11488889

RESUMO

PURPOSE: To study the efficacy of extensive coverage of the brain surface with subdural grids in defining extratemporal cortical areas amenable for resection in patients with refractory extratemporal epilepy (R-ExTE) and normal or nonlocalizing magnetic resonance imaging (MRI) scans. METHODS: Sixteen patients with R-ExTE were studied. Eleven patients had simple partial, eight had complex partial, and three had supplementary motor area seizures. Seizure frequency ranged from three per month to daily episodes. Interictal EEG showed large focal spiking areas in 11 patients, secondary bilateral synchrony in four, and was normal in one patient. Surface ictal recordings were nonlocalizing in six patients, and in 10, they disclosed large ictal focal spiking areas. MRI was normal in 10 patients, and in six patients, focal nonlocalizing potentially epileptogenic lesions were found. All patients were given an extensive coverage of the cortical convexity with subdural electrodes through large unilateral (n = 13) or bilateral (n = 3) craniotomies. Bipolar cortical stimulation was carried out through the implanted electrodes. RESULTS: Interictal invasive recording findings showed widespread spiking areas in 13 patients and secondary bilateral synchrony in three. Ictal invasive recordings showed focal seizure onset in all patients. There were six frontal, two parietal, one temporooccipital, four rolandic, and three posterior quadrant resections. Thirteen patients had been rendered seizure free after surgery, and three had > or =90% of seizure-frequency reduction. Pathologic findings included gliosis (n = 10), cortical dysplasia (n = 5), or no abnormalities (n = 1). Six patients had transient postoperative neurologic morbidity. CONCLUSIONS: Extensive subdural electrodes coverage seems to be an effective way to investigate patients with R-ExTE and normal or nonlocalizing MRI findings.


Assuntos
Córtex Cerebral/fisiopatologia , Córtex Cerebral/cirurgia , Epilepsia/diagnóstico , Epilepsia/cirurgia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Criança , Craniotomia , Estimulação Elétrica , Eletrodos Implantados , Eletroencefalografia/métodos , Eletroencefalografia/estatística & dados numéricos , Epilepsia/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Monitorização Fisiológica , Córtex Motor/fisiopatologia , Córtex Motor/cirurgia , Cuidados Pré-Operatórios/métodos , Espaço Subdural , Resultado do Tratamento , Gravação de Videoteipe
12.
Eur J Med Res ; 5(10): 455-9, 2000 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-11076789

RESUMO

OBJECTIVES: The aim of this study was to investigate the influence of fluconazole, an antimycotic on phagocytosis, oxidative burst and killing activity of phagocytes in human whole blood with Candida albicans as a test strain using a flow cytometric method. METHODS: Candida albicans was stained with Calcein AM, a greenfluorescent dye from Bioprobes (Molecular Probes, Inc., P.O. Box 22010, Eugene, OR 97402-0469, USA). To measure phagocytosis and burst activity diluted monoclonal antibody (CD-13-R-PE, Molecular Probes, Inc., P.O. Box 22010, Eugene, OR 97402-0469, USA) attaching at the surface of granulocytes and monocytes was added as well as Dihydroethidium solution (Molecular Probes, Inc., P.O. Box 22010, Eugene, OR 97402-0469, USA) which changes into red fluorescent Ethidium by oxidation when killing activity takes place. With Ethidium-Homodimer-1-solution (Molecular Probes, Inc., P.O. Box 22010, Eugene, OR 97402-0469, USA) killing activity can be observed. Three different tests, one incubating the Candida for 1- 4 hrs in advance, another incubating whole blood for 1 h, and the third incubating neither yeast nor blood, and a combined main test were carried out. Measurement of phagocytosis, burst- and killing activtiy was performed with a flow cytometric method (Coulter Company, type: Epics-Profile II). RESULTS: Three different concentrations of fluconazole (5, 20 and 100 microg/ml) show neither decreasing nor increasing influence on phagocytosis and burst activity, irrespective of whether yeasts or phagocytes had been incubated with fluconazole in advance or not. Also after incubating the drug with phagocytes for 1 h, neither an increase nor a decrease of killing activity was observed. A significant increase was, however, found with increasing incubation time of yeasts and fluconazole. - The minimum concentration of fluconazole, just enough to show a significant increase of the killing rate was 1 microg/ml after 3hrs of incubation. No further significant increase was detected when the concentration exceeded 5 microg/ml. CONCLUSION: 1 h incubation of human phagocytes with fluconazole does not have any significant influence on cellular activities. After advanced incubation of Candida a corresponding increase of the intracellular killing rate in phagocytes occurs, probably due to changes of the cytomorphology of yeasts.


Assuntos
Antifúngicos/farmacologia , Fluconazol/farmacologia , Fagócitos/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Explosão Respiratória/efeitos dos fármacos , Candidíase/tratamento farmacológico , Candidíase/imunologia , Citometria de Fluxo , Humanos , Fagócitos/imunologia , Fagocitose/imunologia , Explosão Respiratória/imunologia
13.
Bioorg Med Chem ; 8(1): 181-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10968277

RESUMO

Structure activity relationship studies led to the discovery of 4-(3-pentylamino)-2,7-dimethyl-8-(2-methyl-4-methoxyphenyl)-pyrazo lo-[1,5-a]-pyrimidine 11-31 (DMP904), whose pharmacological profile strongly supports the hypothesis that hCRF1 antagonists may be potent anxiolytic drugs. Compound 11-31 (hCRF1 Ki = 1.0+/-0.2 nM (n = 8)) was a potent antagonist of hCRF1-coupled adenylate cyclase activity in HEK293 cells (IC50= 10.0+/-0.01 nM versus 10 nM r/hCRF, n = 8); alpha-helical CRF(9-41) had weaker potency (IC50 = 286+/-63 nM, n = 3). Analogue 11-31 had good oral activity in the rat situational anxiety test; the minimum effective dose for 11-31 was 0.3 mg/kg (po). Maximal efficacy (approximately 57% reduction in latency time in the dark compartment) was observed at this dose. Chlordiazepoxide caused a 72% reduction in latency at 20 mg/kg (po). The literature compound 1 (CP154526-1, 30 mg/kg (po)) was inactive in this test. Compound 11-31 did not inhibit open-field locomotor activity at 10, 30, and 100 mg/kg (po) in rats. In beagle dogs, this compound (5 mg/kg, iv, po) afforded good plasma levels. The key iv pharmacokinetic parameters were t1/2, CL and Vd,ss values equal to 46.4+/-7.6 h. 0.49+/-0.08 L/kg/h and 23.0+/-4.2 L/kg, respectively. After oral dosing, the mean Cmax, Tmax t1/2 and bioavailability values were equal to 1260+/-290 nM, 0.75+/-0.25 h. 45.1+/-10.2 h and 33.1%, respectively. The overall rat behavioral profile of this compound suggests that it may be an anxiolytic drug with a low motor side effect liability.


Assuntos
Ansiolíticos/farmacologia , Hormônio Liberador da Corticotropina/antagonistas & inibidores , Pirazóis/farmacologia , Pirimidinas/farmacologia , Animais , Ansiolíticos/síntese química , Ansiolíticos/química , Linhagem Celular , Cães , Relação Dose-Resposta a Droga , Humanos , Espectroscopia de Ressonância Magnética , Modelos Animais , Ratos
14.
J Vasc Interv Radiol ; 11(3): 327-32, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10735427

RESUMO

PURPOSE: The authors performed a retrospective study of their experience and complication rate while performing outpatient percutaneous transluminal renal artery angioplasty (PTRA) during a 5-year period. MATERIALS AND METHODS: From July 1992 to July 1997, 87 PTRAs were performed. Of these, 62 PTRA procedures were performed on 53 outpatients. In total, 66 arteries were dilated in 62 PTRA sessions using standard, established techniques. During the same period, only 25 PTRAs were performed on inpatients. Angioplasties were performed on those patients with demonstrated renal artery stenosis and poorly controlled hypertension and/or renal failure. Patients chosen for PTRA were picked by a team that included a vascular surgeon, a nephrologist, and a radiologist. Patients who were deemed suitable for an outpatient procedure were recommended by a nephrologist. Radiological input was sought at that time. Specific guidelines were used to select these patients who were otherwise healthy, well-orientated, and able to respond to an emergency situation. None of the subjects had significant risk factors. All were accompanied by an adult for the first 24 hours and all lived no more than an hour's travel time from a hospital. All were stable on discharge and were seen within 24 hours by a nephrologist. RESULTS: The technical success rate, defined as a residual stenosis on imaging of less than 30% and/or by a pressure gradient of less than 10 mm Hg across the stenosis, was 85%. The early complication rate was 5.6%, including two patients who developed a localized hematoma. In all, four patients were admitted to the hospital rather than being discharged to home after an average of 4.2 hours of observation. The late complication rate was 3% and involved two patients. One patient, who reported pain after balloon deflation, was readmitted 6 hours after discharge with hypotension, and a diagnosis of renal artery rupture was confirmed with computed tomography. Another patient developed peripheral atheroemboli 20 days after the procedure. CONCLUSION: Outpatient PTRA can be performed on selected patients. In this study, late complications occurred in only 3% of patients. Early complications were readily recognized in 5.6% of patients, and these patients were admitted for observation after the procedure.


Assuntos
Angioplastia com Balão/métodos , Obstrução da Artéria Renal/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Canadá , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Obstrução da Artéria Renal/diagnóstico por imagem , Estudos Retrospectivos , Resultado do Tratamento
15.
Arch Kriminol ; 204(3-4): 93-105, 1999.
Artigo em Alemão | MEDLINE | ID: mdl-10578446

RESUMO

The paper reflects the current state of the art in forensic linguistics and discusses the fundamental problem of the determination of the significance of linguistic features that are the basis of linguistic reports. A method is proposed that supplements the computer-assisted method of the BKA.


Assuntos
Autoria , Medicina Legal/tendências , Linguística/tendências , Medicina Legal/legislação & jurisprudência , Alemanha , Humanos , Linguística/legislação & jurisprudência
16.
Clin Pharmacol Ther ; 59(6): 675-85, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8681493

RESUMO

OBJECTIVES: Mazapertine is a structurally novel antipsychotic compound with high affinity for D2, D3, 5-HT1a, and alpha 1 receptors. The objectives were to determine whether tolerance to orthostatic hypotension caused by this compound could be induced by slowly increasing the dose administered and to investigate its effect on cognitive and motor functions. METHODS: Thirteen healthy male subjects received incremental oral doses of mazapertine (from 5 to 50 mg over 7 days; n = 10) or placebo (n = 3) in part I and single doses in parts II (20 or 30 mg or placebo) and III (40 mg or placebo) in a double-blind fashion. Blood pressure, heart rate, cardiac hemodynamics, cognitive functions, and occurrence of acute extrapyramidal symptoms were investigated. RESULTS: Mazapertine appears to be safe and well tolerated when administered orally for 7 days to normal healthy men. No accumulation of serum prolactin occurred after multiple dosing, suggesting limited potential for inducing galactorrhea. The drug was rapidly absorbed, and kinetics appeared to be dose dependent, without accumulation. The elimination half-life was about 5 to 10 hours. No evidence of any positive or negative cognitive effects could be detected. Mild motor symptoms were observed only at high doses (not statistically significant). Mazapertine had a minimal effect on cardiac output and stroke volume. Tolerance to hypotension could be induced by slowly increasing the dose administered. CONCLUSIONS: Mazapertine is well tolerated when administered orally for seven days, and tolerance to hypotension can be induced by slowly increasing the dose administered. Therefore, nothing precludes further clinical testing on patients with schizophrenia.


Assuntos
Antipsicóticos/administração & dosagem , Cognição/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Piperazinas/administração & dosagem , Administração Oral , Adulto , Antipsicóticos/farmacocinética , Antipsicóticos/farmacologia , Cromatografia Líquida de Alta Pressão , Antagonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Tolerância a Medicamentos , Meia-Vida , Humanos , Hipotensão Ortostática/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Piperazinas/farmacocinética , Piperazinas/farmacologia , Desempenho Psicomotor/efeitos dos fármacos
17.
Int J Clin Pharmacol Res ; 16(1): 1-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9001924

RESUMO

Tepoxalin, a novel inhibitor of cyclooxygenase (CO) and 5-lipoxygenase (5-LO), was investigated for biochemical activity and pharmacokinetics in two studies. Study I was a 4-period, double-blind, randomized, single rising dose using 2 alternating panels (A, B) with interspersed placebo design (A: 25, 100, 400 mg, B: 50, 200, 800 mg p.o.). Study II was a 3-panel, randomized, placebo-controlled, double-blind, multiple dose study (A: 100 mg, B: 200 mg, C: 400 mg). In both studies, CO inhibition was assessed by generation of serum thromboxane (TxB2), 5-LO activity by LTB4 production ex vivo in Caionophore-stimulated blood. Plasma drug concentrations were assayed by HPLC for tepoxalin and its identified acid metabolite. It was found in both studies that at all dose levels the TxB2 generation was markedly suppressed (> 95% 2 h postdose). In study I, at 2 h postdose, % inhibition of LTB4 biosynthesis was marginal for the 3 lower doses but significant at 200 (14%), 400 (25%) and 800 mg (43%). In study II, the only significant inhibition occurred at the 400 mg dose at 6 h postdose on day 1 (17%) and on day 8 at 4, 6 and 8 h postdose (32, 42 and 32% respectively). In both studies and at all doses, plasma concentrations of tepoxalin varied widely between subjects. Linearity between plasma concentrations and dose could not be ascertained, and correlation between drug plasma levels and effect on LTB4 synthesis was poor. Single doses up to 800 mg and multiple doses up to 400 mg of tepoxalin were generally well tolerated.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/farmacocinética , Inibidores de Ciclo-Oxigenase/farmacologia , Inibidores de Ciclo-Oxigenase/farmacocinética , Inibidores de Lipoxigenase/farmacologia , Inibidores de Lipoxigenase/farmacocinética , Pirazóis/farmacologia , Pirazóis/farmacocinética , Adulto , Área Sob a Curva , Método Duplo-Cego , Gastroenteropatias/induzido quimicamente , Humanos , Leucotrieno B4/biossíntese , Leucotrieno B4/sangue , Testes de Função Hepática , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/farmacologia , Pirazóis/sangue , Tromboxano B2/biossíntese , Tromboxano B2/sangue
18.
Arq Neuropsiquiatr ; 53(2): 203-7, 1995 Jun.
Artigo em Português | MEDLINE | ID: mdl-7487524

RESUMO

The authors report on a series of 214 cases of defined multiple sclerosis according to Poser et al. criteria. These cases were retrospectively selected by medical reports analysed from Santa Casa Medical School (São Paulo) and the private practice, from 1980 to 1993. The data were analysed as for sex, race, onset age of symptoms, onset symptoms, and evolutive symptoms. The results were compared to those found in other Brazilian series and in foreign series. This comparative analysis allows to verify similarities and differences among the several series, and the authors emphasize the necessity of multicentric studies in Brazil to assert with more details the multiple sclerosis profile in our country.


Assuntos
Esclerose Múltipla/diagnóstico , Adulto , Brasil , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/líquido cefalorraquidiano , Exame Neurológico , Estudos Retrospectivos , Fatores Sexuais
19.
Transplantation ; 58(8): 891-8, 1994 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-7940732

RESUMO

A multicenter randomized trial was performed to compare two immunosuppressive protocols after first ABO-compatible liver transplantation. Forty six patients were randomized to a 14-day treatment with Orthoclone (OKT3) in association with steroids and azathioprine, cyclosporine being progressively introduced on day 11 posttransplant. Fifty patients were randomized to a standard protocol of cyclosporine with steroids and azathioprine. Minimum follow-up was 1 year and graft and patient survivals were updated for the purpose of the study. The cumulative 1-year incidence of acute rejection tended to be greater in the cyclosporine group (75%) than in the OKT3 group (67%), especially when patients who did not receive full-course treatment with OKT3 were excluded (59%). Renal function was better preserved during the first two postoperative weeks in the OKT3 group than in the control group but plasma creatinine levels were comparable in both groups thereafter. The incidence of severe infections was lower in the OKT3 group (13.6%) than in the cyclosporine group (32%). The 4-year incidences of patient and graft survival in the OKT3 group (69% and 61%, respectively) were not different from those in the cyclosporine group (62% versus 54%, respectively). Thus this prospective trial shows that OKT3 immunoprophylaxis is a safe alternative to cyclosporine immunoprophylaxis in unselected recipients of a first liver graft.


Assuntos
Ciclosporina/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Transplante de Fígado/imunologia , Muromonab-CD3/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Sobrevivência de Enxerto/imunologia , Humanos , Lactente , Recém-Nascido , Rim/fisiologia , Transplante de Fígado/mortalidade , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
20.
Pediatr Nephrol ; 8(3): 338-42, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7917862

RESUMO

This was an open-label multicentre study of recombinant human erythropoietin (r-HuEPO) in 116 children aged 6 months to 20 years with anaemia of chronic renal failure undergoing haemodialysis. Haemoglobin concentration at entry ranged from 3.4 to 9.5 g/dl. r-HuEPO was given intravenously two or three times per week, the starting dose being 75 U/kg per week. This was subsequently titrated in steps of 75 U/kg per week with the goal of increasing haemoglobin concentration at the rate of 1 g/dl per 4 weeks into the range 9.6-11.2 g/dl (6-7 mmol/l), with treatment then continued for up to 1 year with the aim of maintaining the haemoglobin concentration within the target range. Of the 115 children in whom efficacy could be evaluated, 93 (81%) achieved the target haemoglobin and a further 6 had a rise in haemoglobin concentration of at least 2 g/dl. At 52 weeks, the median maintenance dose for children < 30 kg was 225 U/kg per week, compared with 107 U/kg per week for children > or = 30 kg. Analysis suggested that 150 U/kg per week would have been a more appropriate starting dose. The mean transfusion requirement fell from 8.9 to 0.7 units/patient per year. Of the 22 patients who failed to reach the target, 15 went on to transplantation and left the study prematurely. Sub-group analysis showed that similar doses lead to similar rates of rise in haemoglobin regardless of the severity of the original anaemia. Assessment of quality of life suggested that this may have improved with r-HuEPO.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anemia/terapia , Eritropoetina/uso terapêutico , Falência Renal Crônica/complicações , Diálise Renal , Adolescente , Adulto , Anemia/sangue , Anemia/etiologia , Pressão Sanguínea , Criança , Pré-Escolar , Eritropoetina/administração & dosagem , Eritropoetina/efeitos adversos , Feminino , Hemoglobinas/análise , Humanos , Lactente , Injeções Intravenosas , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Qualidade de Vida , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico
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