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1.
J Fish Biol ; 92(5): 1590-1603, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29624686

RESUMO

Migration of wild and cultivated juvenile honmoroko Gnathopogon caerulescens of from the spawning and nursery areas in Lake Biwa were investigated, both in the Ibanaiko Lagoon and its outlet to Daido River, using beam-trawl surveys in 2013 and 2014. The study demonstrated migration of G. caerulescens from a nursery lagoon toward Lake Biwa after the juvenile stage. These findings appear to be the first direct evidence for migration of an exclusively pelagic cyprinid species from a littoral nursery to a pelagic adult habitat in a large deep lake.


Assuntos
Migração Animal , Cyprinidae/fisiologia , Animais , Cyprinidae/crescimento & desenvolvimento , Ecossistema , Japão , Lagos , Rios
2.
J Theor Biol ; 386: 55-61, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26382230

RESUMO

A leading edge vortex exists on the upper surface of an autorotating plant seed. The vortex enhances the vertical aerodynamic force acting on the seed and decreases the rate of descent. We analyzed the flight data of rotary seeds and revealed that the lift-drag ratio affects the descent factor more strongly than the vertical force coefficient. This has also been confirmed by falling tests of model rotors, which have various aspect ratios, airfoil shapes and total masses.


Assuntos
Modelos Biológicos , Rotação , Sementes/fisiologia , Algoritmos , Fenômenos Biomecânicos , Reologia , Sementes/anatomia & histologia , Árvores/anatomia & histologia , Árvores/fisiologia
3.
J Neural Eng ; 6(1): 014001, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19104141

RESUMO

Neuronal network output in the cortex as a function of synapse density during development has not been explicitly determined. Synaptic scaling in cortical brain networks seems to alter excitatory and inhibitory synaptic inputs to produce a representative rate of synaptic output. Here, we cultured rat hippocampal neurons over a three-week period to correlate synapse density with the increase in spontaneous spiking activity. We followed the network development as synapse formation and spike rate in two serum-free media optimized for either (a) neuron survival (Neurobasal/B27) or (b) spike rate (NbActiv4). We found that while synaptophysin synapse density increased linearly with development, spike rates increased exponentially in developing neuronal networks. Synaptic receptor components NR1, GluR1 and GABA-A also increase linearly but with more excitatory receptors than inhibitory. These results suggest that the brain's information processing capability gains more from increasing connectivity of the processing units than increasing processing units, much as Internet information flow increases much faster than the linear number of nodes and connections.


Assuntos
Neurônios/fisiologia , Sinapses/fisiologia , Potenciais de Ação , Análise de Variância , Animais , Células Cultivadas , Hipocampo/fisiologia , Imuno-Histoquímica , Microeletrodos , Ratos , Receptores de AMPA/metabolismo , Receptores de GABA-A/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptofisina/metabolismo
4.
J Pharm Biomed Anal ; 153: 126-134, 2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-29477928

RESUMO

The present contribution aims to design new-generation bar adsorptive microextraction (BAµE) devices that promote an innovative and much better user-friendly analytical approach. The novel BAµE devices were lab-made prepared having smaller dimensions by using flexible nylon-based supports (7.5 × 1.0 mm) coated with convenient sorbents (≈ 0.5 mg). This novel advance allows effective microextraction and back-extraction ('only single liquid desorption step') stages as well as interfacing enhancement with the instrumental systems dedicated for routine analysis. To evaluate the achievements of these improvements, four antidepressant agents (bupropion, citalopram, amitriptyline and trazodone) were used as model compounds in aqueous media combined with liquid chromatography (LC) systems. By using an N-vinylpyrrolidone based-polymer phase good selectivity and efficiency were obtained. Assays performed on 25 mL spiked aqueous samples, yielded average recoveries in between 67.8 ±â€¯12.4% (bupropion) and 88.3 ±â€¯12.1% (citalopram), under optimized experimental conditions. The analytical performance also showed convenient precision (RSD < 12%) and detection limits (50 ng L-1), as well as linear dynamic ranges (160-2000 ng L-1) with suitable determination coefficients (r2 > 0.9820). The application of the proposed analytical approach on biological fluids showed negligible matrix effects by using the standard addition methodology. From the data obtained, the new-generation BAµE devices presented herein provide an innovative and robust analytical cycle, are simple to prepare, cost-effective, user-friendly and compatible with the current LC autosampler systems. Furthermore, the novel devices were designed to be disposable and used together with negligible amounts of organic solvents (100 µL) during back-extraction, in compliance with the green analytical chemistry principles. In short, the new-generation BAµE devices showed to be an eco-user-friendly approach for trace analysis of priority compounds in biological fluids and a versatile alternative over other well-stablished sorption-based microextraction techniques.


Assuntos
Antidepressivos/química , Microextração em Fase Líquida/métodos , Microextração em Fase Sólida/métodos , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Polímeros/química , Solventes/química , Água/química
5.
Mol Cell Biol ; 15(11): 6398-405, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7565792

RESUMO

Human pro-tumor necrosis factor (pro-TNF) is a type II transmembrane protein with a highly conserved 76-residue leader sequence. We have analyzed the behavior, both in a microsomal translocational system and by transfection, of a series of mutants with deletions from the cytoplasmic, transmembrane, and linking domains. Cytoplasmic deletions included the Arg doublet at -49 and -48 and/or the Lys doublet at -58 and -57; additional mutants included deletion of residues -73 to -55 and -73 to -55, -49, and -48. The transmembrane and linking domain mutants included deletions in the -42 to -35 region, combined with the deletion of residues -32 to -1. Two hybrid mutants combined the cytoplasmic deletions with the deletion of residues -32 to -1. All of the cytoplasmic deletion mutants were properly translocated, as were the transmembrane deletion mutants with deletions up to residues -36, -35, -32 to -1, although the last one exhibited reduced efficiency; further incremental deletions, including deletions of residues -38 to -35 and -32 to -1, completely blocked translocation. Both hybrid mutants were effectively translocated; furthermore, transfection analysis revealed competent expression and maturation of both the cytoplasmic and hybrid mutants. Thus, proper expression and maturation of human pro-TNF can be accomplished with as few as approximately 12 of the 26 residues of the native transmembrane domain and with a net negative charge in the cytoplasmic domain flanking the transmembrane region.


Assuntos
Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Sinais Direcionadores de Proteínas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico , Membrana Celular/metabolismo , Sistema Livre de Células , Células Cultivadas , Chlorocebus aethiops , Cães , Retículo Endoplasmático Rugoso/metabolismo , Humanos , Íons , Dados de Sequência Molecular , RNA Mensageiro/genética , Deleção de Sequência , Relação Estrutura-Atividade
6.
J Pharm Biomed Anal ; 129: 593-599, 2016 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-27519155

RESUMO

In this study, the enhancement for trace analysis of sulfonamide antibiotics (sulfathiazole, sulfamethoxazole and sulfadimethoxine) and trimethoprim in water matrices is proposed using bar adsorptive microextraction combined with micro-liquid desorption followed by high-performance liquid chromatography with diode array detection (BAµE-µLD/HPLC-DAD). By comparing different polymers and activated carbons as sorbent coatings for BAµE, the polystyrene-divinylbenzene polymer (PS-DVB) showed the best selectivity for the compounds under study. Assays performed through BAµE(PS-DVB)-µLD on 25mL of ultrapure water samples spiked at the 8.0µgL(-1) level showed recoveries ranging from 63.8±1.5% to 84.2±1.9%, under optimized experimental conditions. The validated method provided satisfactory limits of detection (0.08-0.16µgL(-1)) and good linear dynamic ranges (0.16-8.00µgL(-1)) with determination coefficients higher than 0.9958. The proposed analytical methodology was applied to real matrices, such as tap, estuarine and wastewater samples using the standard addition method. It showed to be easy to implement, with good reproducibility, sensitivity and requiring small amount of sample. Furthermore, negligible consumption of organic solvents was used in compliance with the green analytical chemistry principles. When compared to other well-established microextraction approaches, BAµE demonstrated better performance concerning recovery yields and sensitivity.


Assuntos
Antibacterianos/química , Sulfanilamidas/química , Águas Residuárias/análise , Água/química , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Reprodutibilidade dos Testes , Microextração em Fase Sólida/métodos , Sulfanilamida , Poluentes Químicos da Água/química
7.
Chemosphere ; 135: 257-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25965005

RESUMO

We aimed to evaluate the ecological integrity of a large river, which receives agricultural and urban effluents and is used to water public supply. The fish species Astyanax bifasciatus was used as bioindicator during winter and spring 2012, and summer 2013 at the Middle Iguaçu River basin in Paraná state, Brazil. Water chemical and physical measures and ecotoxicological tests were carried out as well biochemical and genetic biomarkers in sampled fish in each period. The studied area was divided in three sample points: SP1, located where the water is collected to public supply; SP2, located in an urbanized area, and SP3, located at an urbanized area with the discharge of the sewage treatment. Although water chemical and physical analyzes were range of the Brazilian law to hydric bodies, anticholinesterasic effects were found in winter, oxidative stress in summer and spring. The higher genotoxic effect was in winter to all sample points. The temporal variation in biomarkers and the detection of caffeine in the water call attention to the water quality in this river mainly to be used to public supply.


Assuntos
Monitoramento Ambiental/métodos , Peixes/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/metabolismo , Brasil , Rios , Estações do Ano , Água , Poluentes Químicos da Água/análise , Qualidade da Água , Abastecimento de Água
8.
FEBS Lett ; 242(2): 255-8, 1989 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-2914608

RESUMO

The interaction of ricin and its constituent polypeptides, the A- and B-chain, with small unilamellar vesicles of dipalmitoylphosphatidylcholine (DPPC) or dimyristoylphosphatidylcholine (DMPC) was investigated by means of differential scanning calorimetry measurements. The A-chain, at neutral pH, entirely shifted the endothermic peak of small unilamellar vesicles of DPPC from 37 degrees C to 41 degrees C at low protein/lipid ratios. The potency of either ricin or the B-chain to induce the shift of endothermic peak was much less than that of the A-chain. The A-chain was also found to cause mixing of endothermic peaks of DMPC vesicles and DPPC vesicles. These data strongly suggest that the A-chain has the ability to induce fusion of phospholipid vesicles.


Assuntos
Fusão de Membrana/efeitos dos fármacos , Fosfatidilcolinas , Ricina/farmacologia , Varredura Diferencial de Calorimetria , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas
9.
FEBS Lett ; 238(1): 13-6, 1988 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-3169245

RESUMO

A hydrophilic enzyme, lysozyme, was myristoylated in vitro by the N-hydroxysuccinimide ester of myristic acid, and the monomyristoylated lysozyme was isolated by CM-cellulose cation-exchange column chromatography. The monomyristoylated lysozyme associated with phospholipid vesicles, whereas the association of native lysozyme was negligible. The membrane-associated monomyristoylated lysozyme was phosphorylated with partially purified rat brain Ca2+- and phospholipid-dependent protein kinase (protein kinase C) in the presence of Ca2+, phosphatidylserine and phorbolmyristate acetate. Thus, the myristoylated lysozyme became a substrate of protein kinase C through its hydrophobic association with the membrane. The present results suggest that the myristoylation of cytoplasmic proteins may have an important role in signal transduction.


Assuntos
Encéfalo/enzimologia , Lipoproteínas/metabolismo , Proteínas de Membrana/metabolismo , Muramidase/metabolismo , Ácidos Mirísticos/metabolismo , Proteína Quinase C/metabolismo , Animais , Cinética , Ácido Mirístico , Fosforilação , Proteína Quinase C/isolamento & purificação , Ratos
10.
J Comp Neurol ; 410(2): 235-42, 1999 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-10414529

RESUMO

We have determined different patterns of fissurization in Broca's area, the gyrus of Heschl, the planum temporale, the inferior parietal lobe, and the cingulate sulcus. Such patterns were asymmetrically distributed, indicating increased folding on the left side in most cases. More folding can sometimes be related to a larger cortical area, resulting in increased processing capacities in the respective brain region. Furthermore, the brain regions associated with the asymmetrical sulci are involved in lateralized functions. Of special interest are the asymmetries observed in regions corresponding to the inferior parietal lobe (the accessory postcentral sulcus and the intraparietal sulcus), which, according to recent studies, is involved in linguistic working memory. We did not detect a tendency of distinct fissurization patterns in a given brain region to be associated with specific patterns in other fissures, indicating that the different fissure types develop independently in each brain region and can therefore be determined by local processes. These descriptions are of relevance to imaging studies that intend to establish correspondences between gross morphology and functional parameters such as behavior and brain activation.


Assuntos
Lateralidade Funcional/fisiologia , Giro do Cíngulo/anatomia & histologia , Lobo Temporal/anatomia & histologia , Adulto , Idoso , Mapeamento Encefálico , Técnicas de Cultura , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Giro do Cíngulo/fisiologia , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Lobo Temporal/fisiologia
11.
J Biochem ; 95(4): 1083-90, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6086592

RESUMO

The effects of various synthetic peptides on basal and ACTH-stimulated lipolysis in fat cells were examined. Glu-Arg-Gly-Phe-Phe-Phe possessed lipolytic activity and increased ACTH-stimulated lipolysis at concentrations higher than 0.5 mumol/ml. Glu-Arg-Gly-Phe-Phe-Tyr did not cause any release of FFA from fat cells. Glu-Arg-Gly-Leu-Leu-Leu had no lipolytic activity but inhibited ACTH-stimulated lipolysis at concentrations higher than 0.25 mumol/ml. Glu-Arg-Gly-Leu-Leu-Leu also inhibited epinephrine-stimulated lipolysis. The effects of the peptides on basal and insulin-stimulated lipogenesis in fat cells were examined. Glu-Arg-Gly-Phe-Phe-Tyr increased both basal and insulin-stimulated lipogenesis. A tripeptide, Glu-Arg-Gly, inhibited both basal and insulin-stimulated lipogenesis. Glu-Arg-Gly-Leu-Leu-Leu had no effect on either basal or insulin-stimulated lipogenesis. Glu-Arg-Gly-Phe-Phe-Phe and ACTH, which elicit FFA release from fat cells, also stimulated formation of [14C]triglyceride from [14C]glucose.


Assuntos
Tecido Adiposo/metabolismo , Hormônio Adrenocorticotrópico/farmacologia , Lipídeos/biossíntese , Lipólise/efeitos dos fármacos , Oligopeptídeos/farmacologia , Tecido Adiposo/efeitos dos fármacos , Animais , Cinética , Masculino , Oligopeptídeos/síntese química , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade
12.
J Biochem ; 125(3): 531-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10050041

RESUMO

Immortal human fibroblasts, SVts8 cells, which express a heat-labile SV40 large T antigen, induces a senescence-like phenomenon in response to upward shift in temperature. Cells with arrested division show strong induction of senescence-associated beta-galactosidase. We examined how p53 and pRB are involved in this phenomenon since they are major targets of the T antigen. Transfection of cells with plasmids encoding the wild-type T antigen or human papilloma virus type 16 E6/E7 proteins completely abolished the arrest in cell division, a plasmid encoding the E6 protein suppressed it markedly, while a plasmid encoding E7 had no effect. Plasmids encoding dominant-negative p53 mutants also suppressed the arrest in cell division to various degrees. Upon temperature shift, p21 mRNA was upregulated 10-fold in SVts8 cells, but only slightly in clones expressing the wild-type T antigen or dominant-negative p53 mutants. These data demonstrate that p53 plays a major role in this senescence-like phenomenon.


Assuntos
Antígenos Transformantes de Poliomavirus/genética , Transformação Celular Viral/genética , Fibroblastos/fisiologia , Regulação da Expressão Gênica , Proteína Supressora de Tumor p53/genética , Antígenos Transformantes de Poliomavirus/biossíntese , Divisão Celular/genética , Linhagem Celular Transformada , Fibroblastos/patologia , Humanos , Mutação , Temperatura
13.
Brain Res ; 890(2): 330-2, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11164799

RESUMO

The postcentral sulcus has two fissurization patterns: (I) the sulcus extends continuously into the sylvian fissure; (II) the sulcus is interrupted in its trajectory. In the left but not in the right hemisphere, there was a sex difference in the distribution of these fissural patterns, type I being more frequent in men and type II being more frequent in women. No hemispheric asymmetry was found for these patterns in either sex.


Assuntos
Lateralidade Funcional/fisiologia , Caracteres Sexuais , Córtex Somatossensorial/anatomia & histologia , Adulto , Idoso , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Pessoa de Meia-Idade , Córtex Somatossensorial/fisiologia , Percepção Espacial/fisiologia , Comportamento Verbal/fisiologia
14.
Neurosci Lett ; 233(2-3): 141-4, 1997 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-9350852

RESUMO

We studied effects of various sigma ligands on GTPase activity in mouse prefrontal membranes. Some representative sigma agonists, such as (+)-pentazocine, SA4503 and (+)-3-PPP, stimulated the GTPase activity in a concentration-dependent manner in ranges of 10 nM to 10 microM. Maximal effect was almost 10% increase to the control without treatment of drugs. However, another representative agonist, (+)-SKF10,047 showed only a partial activity with maximal effect 5% at 1 microM. NE-100, a representative antagonist, showed no effect at concentrations not more than 100 nM, while it did stimulate GTPase activity at 1 and 10 microM. Furthermore, these stimulative effects of both (+)-pentazocine and SA4503 on GTPase activity were significantly antagonized by NE-100 at 100 nM, suggesting that NE-100 possesses agonist-antagonist property. These findings suggest the possibility that there exist metabotropic sigma receptors.


Assuntos
Córtex Pré-Frontal/metabolismo , Receptores sigma/efeitos dos fármacos , Animais , GTP Fosfo-Hidrolases/efeitos dos fármacos , Ligantes , Modelos Logísticos , Masculino , Membranas/metabolismo , Camundongos , Camundongos Endogâmicos , Estimulação Química
15.
Free Radic Res ; 21(4): 223-34, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7827694

RESUMO

Mouse liver mitochondria were uncoupled in a time dependent by intraperitoneal injection of a radical initiator, 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH) (100 mg/kg). State 3 respiration, ADP/O ratio and respiratory control ratio (RCR) were decreased 30 min after injection but there was no effect on state 4 respiration. Lipid peroxidation was increased and oxidative phosphorylation was uncoupled at one hr after drug injection but gradually recovered to normal levels after 14 hr in vivo. State 3 respiration, RCR and ADP/O ratio but not state 4 respiration of isolated mouse mitochondria were inhibited by short term incubation with AAPH in vitro. This inhibitory action was concentration dependent (ID50 = 5 mM) but was not prevented by alpha-tocopherol. AAPH had no effect on electron transport or the membrane potential of these isolated mitochondria. However, mitochondria were uncoupled via lipid peroxidation and swelling by long term incubation with AAPH. These inhibitory effects of AAPH were reduced by its spontaneous degradation not only in vitro but also in vivo. Thus AAPH induces mitochondrial dysfunction by direct action in the early period of treatment and free radicals produced from AAPH mediate mitochondrial swelling via lipid peroxidation in the late period. From these findings, it is concluded that mitochondrial phosphorylation plays an important role in the pathogenesis of liver injury induced by AAPH and that radicals generated by AAPH might be a source of liver injury and mitochondrial dysfunction in vivo.


Assuntos
Amidinas/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Radicais Livres , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias Hepáticas/fisiologia , Dilatação Mitocondrial/efeitos dos fármacos , Fosforilação/efeitos dos fármacos
16.
Free Radic Res ; 24(4): 281-9, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8731012

RESUMO

Effects of various derivatives of alpha-tocopherol (VE) and coenzyme Q (CoQ) on superoxide (O2.-) generation of neutrophils and protein kinase C (PKC) activity were examined. VE and CoQ8 inhibited O2.- generation of neutrophils stimulated by a protein kinase C mediated process monitored by cytochrome c reduction and spin trapping methods. The inhibitory action was observed not only with alpha-tocopherol, but also with beta-, gamma-, delta-tocopherols and with tocol which is a chemical similar to VE but lacking methyl groups on the chromanol ring structure and which is not a radical scavenger. By contrast, no inhibition was observed with 2-carboxy-2, 5, 7, 8-tetramethyl-6-chromanol (CTMC, trolox) or 2, 2, 5, 7, 8,-pentamethyl-6-chromanol (PMC) which are water soluble VE derivatives having radical scavenging activity. Compounds having a similar isoprenoid chain, such as CoQ, also have inhibitory activity on PKC-dependent O2.- generation of neutrophils. The inhibitory activity of CoQ derivatives is dependent on the length of the unsaturated isoprenoid chain. CoQ derivatives having 16, 24 and 32 carbon isoprenoid chains corresponding to CoQ4, 6, and 8 inhibited O2.- generation but 4 and 40 carbon isoprenoid chains corresponding to CoQ2 and 10 had no inhibitory activity on O2.- generation. Alpha-tocopherol and CoQ inhibited PKC activity but the ID50 for O2.- generation and PKC activity was different for each compound. However, no direct relationship between VE content and O2.- generation of neutrophils was observed. These results suggest that isoprenoids of VE and CoQ participate in the inhibition of the NADPH oxidase activation system through modulation of the neutrophil membrane probably by the inhibition of PKC.


Assuntos
Antioxidantes/farmacologia , Neutrófilos/fisiologia , Superóxidos/metabolismo , Ubiquinona/farmacologia , Vitamina E/farmacologia , Animais , Calcimicina/farmacologia , Espectroscopia de Ressonância de Spin Eletrônica , Cobaias , Radical Hidroxila/metabolismo , Técnicas In Vitro , Cinética , Neutrófilos/efeitos dos fármacos , Cavidade Peritoneal , Proteína Quinase C/metabolismo , Ratos , Acetato de Tetradecanoilforbol/farmacologia , Vitamina E/análogos & derivados , Zimosan/farmacologia
17.
Phytochemistry ; 50(5): 805-13, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10192965

RESUMO

Chemical examination of the aerial parts of Dracaena draco has led to the isolation of a total of nine steroidal saponins, including five new ones. The structures of the new saponins were determined by spectral data and a few chemical transformations to be (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23,24-tetrol 1-O-{O-(2,3,4-tri-O-acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L -arabinopyranosyl} 24-O-beta-D-fucopyranoside, (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta, 23,24-tetrol 1-O-{O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L -arabinopyranoside}, (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23,24-tetrol 1-O-{O-(4-O- acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L-arabinopyransoide} , (23S)-spirosta-5,25(27)-diene-1 beta,3 beta,23-triol 1-O-{O-alpha-L- rhamnopyranosyl)-(1-->2)-alpha-L-arabinopyranoside} and (23S,24S)-spirosta-5,25(27)-diene-1 beta,3 beta,23-triol 1-O-{O-(4-O-acetyl-alpha-L-rhamnopyranosyl)-(1-->2)-alpha-L- arabinopyranoside}. The isolated saponins were evaluated for their cytostatic activity on leukemia HL-60 cells.


Assuntos
Antineoplásicos Fitogênicos/química , Células HL-60/efeitos dos fármacos , Plantas Medicinais , Saponinas/química , Espirostanos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Humanos , Conformação Molecular , Estrutura Molecular , Saponinas/isolamento & purificação , Saponinas/toxicidade , Espirostanos/isolamento & purificação , Espirostanos/toxicidade
18.
Thyroid ; 10(11): 975-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11128725

RESUMO

Thirty-two patients with differentiated thyroid carcinomas with distant metastasis were examined using a radioactive iodine (131I) tracer dose prior to 131I therapy and followed up for 10 years or until death (whichever occurred first). Nineteen patients who received 131I therapy had an accumulation of 131I in the metastases (group I) and 15 of those patients were alive more than 10 years after the first 131I treatment. In contrast, all 13 patients in whom the metastases did not show accumulation of 131I died within 10 years. Of the latter group, eight patients had received 131I therapy (group II), four of whom died with anaplastic changes within 5 years of treatment. p53 gene mutation was identified by immunohistochemistry in primary thyroid carcinoma tissue from patients with anaplastic changes that were evident during total thyroidectomy. Five patients did not receive 131I therapy (group III), of whom one, who also had a p53 gene mutation in the original tumor, died with anaplastic change 10 years after thyroidectomy. Seven patients in group I had p53 gene mutations in their thyroid carcinoma tissues, but none showed anaplastic changes. Our results suggest that 131I therapy may be useful for patients with distant metastases, with or without p53 gene mutations, which show accumulation of 131I from tracer and therapeutic doses. In contrast, 131I therapy is apparently not effective in patients who do not show sufficient accumulation of 131I, but rather, may cause early anaplastic changes with a p53 gene mutation.


Assuntos
Carcinoma Papilar/radioterapia , Carcinoma Papilar/secundário , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/secundário , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Carcinoma Papilar/genética , Diferenciação Celular , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação/efeitos da radiação , Radioterapia/normas , Neoplasias da Glândula Tireoide/genética , Proteína Supressora de Tumor p53/análise
19.
Thyroid ; 10(8): 641-6, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11014307

RESUMO

Leptin is a protein product of the ob gene, mainly produced by adipocytes. Leptin is thought to play an important role in the homeostasis of body weight by suppressing appetite and increasing energy consumption. The aim of this study was to investigate the possible effect of thyroid hormone on the regulation of the leptin system during suppression of beta-adrenergic receptors in Graves' patients. We studied 15 adult female patients with Graves' disease. Thyroid function, serum levels of leptin, and percent body fat (%BF) were examined at four different clinical conditions during therapy (A, untreated; B, beta-adrenergic antagonist only [A, B; hyperthyroid], C, beta-adrenergic antagonist and antithyroid drug; D, antithyroid drug only [C, D; euthyroid]). The use of beta-adrenergic antagonist significantly reduced heart rate in spite of hyperthyroid state, indicating sufficient suppression of beta-adrenergic receptors. During treatment with beta-adrenergic antagonist, leptin percentage of body fat (%BF) ratio significantly decreased in euthyroid state compared to that in hyperthyroid state (from 38.7 +/- 21.3 to 18.1 +/- 19.3, p = 0.003). Moreover, there was a significantly positive correlation between delta leptin/%BF and delta free thyroxine (FT4) (r = 0.51, p = 0.008). Under a euthyroid state induced by antithyroid drug treatment, leptin/%BF did not change in spite of withdrawal of beta-adrenergic antagonist. Our data indicate that thyroid hormones could increase serum leptin level during suppression of beta-adrenergic receptors in Graves' patients. Our data also suggest that the beta-adrenergic action of thyroid hormones might be partly mediated by regulation of leptin.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Doença de Graves/sangue , Leptina/sangue , Tiroxina/fisiologia , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Idoso , Feminino , Doença de Graves/tratamento farmacológico , Humanos , Pessoa de Meia-Idade
20.
Thyroid ; 10(7): 595-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10958312

RESUMO

The use of propylthiouracil (PTU) for the treatment of Graves' disease is associated with few adverse effects such as skin eruptions, liver dysfunction, and agranulocytosis. Furthermore, recent studies described the development of antineutrophil cytoplasmic antibody (ANCA)-related glomerulonephritis and vasculitis in patients treated with PTU. Here we investigated whether PTU therapy per se is associated with the appearance of ANCA in patients with Graves' disease. We analyzed 119 serum samples from 117 patients with Graves' disease treated with either PTU (n = 56), or methimazole (MMI) (n = 21), as well as untreated patients (n = 42). Myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA were tested by enzyme-linked immunosorbent assay (ELISA) kits. MPO-ANCA was negative in all patients treated with MMI therapy and untreated patients. However, MPO-ANCA was detected in 21 (37.5%) of 56 patients treated with PTU therapy. Furthermore, two patients who were negative for MPO-ANCA became positive after PTU therapy. The proportion of patients positive for MPO-ANCA increased with the prolongation of PTU therapy, but did not correlate with age, gender, and positive antithyroperoxidase (TPO) antibody. Among 21 MPO-ANCA positive patients, 12 had no symptoms, but 9 patients complained of myalgia, arthralgia, or common cold like symptoms after the appearance of MPO-ANCA. Three patients developed agranulocytosis or granulocytopenia, but none showed abnormal urinary findings. Our results suggest that PTU per se is associated with the production of MPO-ANCA in patients with Graves' disease.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Antitireóideos/efeitos adversos , Doença de Graves/tratamento farmacológico , Propiltiouracila/efeitos adversos , Adulto , Idoso , Agranulocitose/imunologia , Antitireóideos/uso terapêutico , Autoanticorpos/sangue , Feminino , Doença de Graves/imunologia , Humanos , Iodeto Peroxidase/imunologia , Masculino , Pessoa de Meia-Idade , Mieloblastina , Peroxidase/imunologia , Propiltiouracila/uso terapêutico , Serina Endopeptidases/imunologia
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