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1.
J Assoc Genet Technol ; 45(4): 180-186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31831721

RESUMO

OBJECTIVES: Disorders of sex development (DSD) include a group of conditions in which genotypes do not correlate with the typical male and female phenotypes. Numerical and structural abnormalities involving both autosomes and sex chromosomes have been observed in DSD. Specifically, deletions, duplications, and translocations involving specific genes as well as point mutations and less common aberrations have been implicated in the pathogenesis of these conditions. Finally, recent advances in analytical tools, namely chromosomal microarrays and sequencing methods, have greatly enhanced the precision with which DSD are genetically characterized and phenotypically correlated. Herein we report a case of a 24-year-old female patient who presented with secondary amenorrhea. Cytogenetic studies of her peripheral blood showed an abnormal clone with 45,X in three cells and the other was initially observed by chromosome analysis as 46,X,+mar in 27 cells. Molecular cytogenetics were performed to characterize the marker chromosome that showed two copies of the SRY, two copies of the heterochromatin Yq12, and two copies of the Y centromere Yp11.1-q11.1 on the marker chromosome, resulting in the identification of an isodicentric Y chromosome. Females with a 46,XY karyotype have gonadal dysgenesis and typically present as mosaic, along with a 45,X cell line. Some show small deletions of the short arm of the Y chromosome. Further studies based on the clinical picture, as well as possible prophylactic gonadectomy due to an increased risk of gonadal malignancy, gonadoblastoma or dysgerminoma, are suggested. Genetic counseling was recommended.

2.
J Clin Pharm Ther ; 34(6): 719-22, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20175806

RESUMO

BACKGROUND AND OBJECTIVE: Pertussis developed in Kagawa University Medical School and University Hospital in May 2007. To control the outbreak and prevent the infection of hospital inpatients, the Infection Control Team (ICT) carried out the prophylactic administration of erythromycin (EM) to hospital staff (1566 staff) who might be exposed to Bordetella pertussis. METHODS: An oral dose of 1000 mg/day EM was given for 10 days. To assess compliance and estimate the frequency of adverse effect, the ICT conducted a questionnaire survey. RESULTS AND DISCUSSION: Of 942 respondents (response rate: 60.2%), 264 (28.0%) experienced some form of EM adverse effects, of which the most commonly reported involved digestive organ symptoms, e.g. diarrhoea (15.6%), stomachache (7.5%), nausea (3.6%), epigastric distress (2.1%) and abdominal distention (1.8%). More importantly, 246 participants (26.1%) stopped taking the EM before completing 10 days because of perceived adverse effects. CONCLUSION: These results indicate that EM appears to cause adverse effects more frequently than reported in the package insert in Japan. The prophylactic use of EM for pertussis infection is recognized in the guideline of the Centers for Disease Control and Prevention. However, this study suggests that attention should be paid to EM non-compliance during a pertussis outbreak, which could extend the duration of the outbreak and increase the number of affected patients.


Assuntos
Antibacterianos/efeitos adversos , Infecção Hospitalar/prevenção & controle , Surtos de Doenças , Eritromicina/efeitos adversos , Coqueluche/epidemiologia , Humanos
3.
J Neurophysiol ; 100(2): 698-707, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18562558

RESUMO

The development of the cerebral cortex depends on genetic factors and early electrical activity patterns that form immature neuronal networks. Subplate neurons (SPn) are involved in the construction of thalamocortical innervation, generation of oscillatory network activity, and in the proper formation of the cortical columnar architecture. Because glycine receptors play an important role during early corticogenesis, we analyzed the functional consequences of glycine receptor activation in visually identified SPn in neocortical slices from postnatal day 0 (P0) to P4 rats using whole cell and perforated patch-clamp recordings. In all SPn the glycinergic agonists glycine, beta-alanine, and taurine induced dose-dependent inward currents with the affinity for glycine being higher than that for beta-alanine and taurine. Glycine-induced responses were blocked by the glycinergic antagonist strychnine, but were unaffected by either the GABAergic antagonist gabazine, the N-methyl-d-aspartate-receptor antagonist d-2-amino-5-phosphonopentanoic acid, or picrotoxin and cyanotriphenylborate, antagonists of alpha-homomeric and alpha1-subunit-containing glycine receptors, respectively. Under perforated-patch conditions, glycine induced membrane depolarizations that were sufficient to trigger action potentials (APs) in most cells. Furthermore, glycine and taurine decreased the injection currents as well as the synaptic stimulation strength required to elicit APs, indicating that glycine receptors have a consistent excitatory effect on SPn. Inhibition of taurine transport and application of hypoosmolar solutions induced strychnine-sensitive inward currents, suggesting that taurine can act as a possible endogenous agonist on SPn. In summary, these results demonstrate that SPn express glycine receptors that mediate robust excitatory membrane responses during early postnatal development.


Assuntos
Córtex Cerebral/citologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Neurônios/classificação , Neurônios/fisiologia , Receptores de Glicina/fisiologia , Animais , Animais Recém-Nascidos , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Interações Medicamentosas , Estimulação Elétrica/métodos , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/efeitos da radiação , Glicina/farmacologia , Glicinérgicos/farmacologia , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Potenciais da Membrana/efeitos da radiação , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp/métodos , Ratos , Estricnina/farmacologia , Taurina/análogos & derivados , Taurina/antagonistas & inibidores , Taurina/farmacologia , beta-Alanina/farmacologia , Ácido gama-Aminobutírico/farmacologia
4.
Br Poult Sci ; 49(3): 273-81, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18568751

RESUMO

1. Inter-breed morphological comparisons were made among 11 breeds of Japanese native chickens (Gifujidori, Hinaidori, Shokoku, Totenko, Tomaru, Satsumadori, Shamo, Koshamo, Koeyoshi, Chabo and Nagoya), White Leghorn, broiler chickens (Chunky) and red junglefowl collected in the Philippines, based on results of direct measurements and analysis by computer vision techniques of the skull. 2. Analysis of direct measurements identified two groups of chicken: a small type that included the Chabo, Koshamo, red junglefowl, Gifujidori and Shokoku and a large type that included the remaining breeds studied. These groupings were made based on size determined both in the first (PC1) and second principal component (PC2). The greatest length of the cranium and condylobasal length greatly contributed to the morphological differences between these two groups. 3. Analysis by computer vision techniques, however, identified three groups: the Bantam group (which includes red junglefowl), Shokoku group and Shamo group. White Leghorn clustered within the Shokoku group while the broiler chicken belonged to the Shamo group. The region around the junction of the neural cranium and the visceral cranium contributed greatly to the morphological differences among breeds, both in the PC1 and PC2.


Assuntos
Galinhas/anatomia & histologia , Galinhas/genética , Crânio/anatomia & histologia , Animais , Galinhas/classificação , Gráficos por Computador , Simulação por Computador , Feminino , Variação Genética , Japão , Masculino , Filogenia , Especificidade da Espécie
5.
Br J Cancer ; 96(11): 1707-10, 2007 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-17486133

RESUMO

To investigate the long-term biological effect of extreme low dose ionising radiation, we irradiated normal human fibroblasts (HFLIII) with carbon ions (290 MeV u(-1), 70 keV microm(-1)) and gamma-rays at 1 mGy (total dose) once at a low dose rate (1 mGy 6-8 h(-1)), and observed the cell growth kinetics up to 5 months by continuous culturing. The growth of carbon-irradiated cells started to slow down considerably sooner than that of non-irradiated cells before reaching senescence. In contrast, cells irradiated with gamma-rays under similar conditions did not show significant deviation from the non-irradiated cells. A DNA double strand break (DSB) marker, gamma-H2AX foci, and a DSB repair marker, phosphorylated DNA-PKcs foci, increased in number when non-irradiated cells reached several passages before senescence. A single low dose/low dose rate carbon ion exposure further raised the numbers of these markers. Furthermore, the numbers of foci for these two markers were significantly reduced after the cells became fully senescent. Our results indicate that high linear energy transfer (LET) radiation (carbon ions) causes different effects than low LET radiation (gamma-rays) even at very low doses and that a single low dose of heavy ion irradiation can affect the stability of the genome many generations after irradiation.


Assuntos
Radioisótopos de Carbono/toxicidade , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Instabilidade Genômica/efeitos da radiação , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Senescência Celular/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Marcadores Genéticos/efeitos da radiação , Humanos , Doses de Radiação
6.
Neuroscience ; 123(3): 715-24, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14706783

RESUMO

Glycinergic membrane responses have been described in cortical plate neurons (CPn) and Cajal-Retzius cells (CRc) during early neocortical development. In order to elucidate the functional properties and molecular identity of glycine receptors in these two neuronal cell types, we performed whole-cell patch-clamp recordings and subsequent single-cell multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analyses on visually identified neurons in tangential and coronal slices as well as in situ hybridizations of coronal slices from neonatal rat cerebral cortex (postnatal days 0-4). In both CPn and CRc the glycinergic agonists glycine, beta-alanine and taurine induced inward currents with larger current densities in CRc. The functional properties of these currents were similar between CPn and CRc. In both cell types the glycine receptor showed a higher affinity for glycine than for the glycinergic agonists beta-alanine and taurine. The glycinergic responses of both cells were blocked by the glycinergic antagonist strychnine and were unaffected by the GABAergic antagonist bicuculline (100 microM), the N-methyl-D-aspartic acid receptor antagonist (+/-)-2-amino-5-phosphonopentatonic acid (60 microM) and by picrotoxin (30 microM), an antagonist of alpha homomeric glycine receptors. Single-cell multiplex RT-PCR revealed the expression of glycine receptor alpha(2) and beta subunits in CPn and CRc, while no alpha(1) and alpha(3) subunits were observed. In situ hybridization histochemistry showed the expression of mRNAs for alpha(2) and beta subunits within the cortical plate and in large neurons of the marginal zone, while there were no signals for alpha(1) and alpha(3) subunits. In summary, these results suggest that CPn and CRc express glycine receptors with similar functional and pharmacological properties. The correlation of pharmacological properties and mRNA expression suggests that the glycine receptors in both cell types may consist of alpha(2)/beta heteromeric receptors.


Assuntos
Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Receptores de Glicina/biossíntese , Animais , Animais Recém-Nascidos , Córtex Cerebral/efeitos dos fármacos , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas GABAérgicos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores de Glicina/genética
7.
Int J Radiat Biol ; 80(11-12): 881-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15764397

RESUMO

PURPOSE: To quantify the Auger effect on chromosomal aberrations via Ca atoms in human cells. MATERIAL AND METHODS: Exponentially growing human normal fibroblasts (GM05389) were irradiated with 4.047 (CaK-P), 4.026 (CaK-L) and 4.067 (CaK-H) keV X-rays (corresponding to the resonance absorption edge of the Ca K-shell and slightly below and slightly above the edge, respectively) using synchrotron radiation at the photon factory (PF) of the High Energy Accelerator Organization located in Tsukuba. Chromosomal aberrations induced by the irradiation were analyzed by the premature chromosome condensation (PCC) method using calyculin A. The dependency of the chromosomal aberrations on the incubation time post 2 Gy irradiation was observed for each energy. Irradiation using 200 kVp conventional X-rays was also examined as a reference to CaK irradiation. RESULTS: (1) Soon after irradiation with 2Gy, the enhancement ratios of CaK-H X-rays to CaK-L X-rays were 1.21, 1.51 and 2.70 for breaks/gaps, isochromatid breaks and exchanges, respectively. The enhancement ratios of CaK-P X-rays to CaK-L X-rays were 1.82, 0.98 and 6.30, for breaks/gaps, isochromatid breaks and exchanges, respectively. (2) After a 6-hr incubation treatment post 2 Gy irradiation, the enhancement ratios of CaK-H X-rays to CaK-L X-rays were 1.59, 2.03 and 2.14 for breaks/gaps, isochromatid breaks and exchanges, respectively. The enhancement ratios of CaK-P X-rays to CaK-L X-rays were 1.69, 1.66 and 2.00 for breaks/gaps, isochromatid breaks and exchanges, respectively. (3) Soon after irradiation, the ratios of the efficiencies of CaK-P X-rays to those of 200 kVp X-rays were 1.74, 1.29 and 2.51 for breaks/gaps, isochromatid breaks and exchanges, respectively. And after a 6-hr incubation treatment, the ratios were 5.50, 1.93 and 1.81 for breaks/gaps, isochromatid breaks and exchanges, respectively. CONCLUSIONS: An effective enhancement of chromosomal aberrations, such as breaks/gaps, isochromatid breaks and exchanges, was caused by Ca K-shell ionization or excitation. Auger electrons emitted by Ca atoms in irradiated cells appear to have an important role in causing this enhancement. Comparing these efficiencies of chromosomal aberrations with those produced by 200 kVp conventional X-rays suggests un-repaired and complicated damage is induced by the X-rays around the Ca K-shell resonance absorption edge.


Assuntos
Cálcio/metabolismo , Aberrações Cromossômicas/efeitos da radiação , Cromossomos/efeitos da radiação , Cromossomos/ultraestrutura , Elétrons/efeitos adversos , Fibroblastos/patologia , Fibroblastos/efeitos da radiação , Cálcio/efeitos da radiação , Linhagem Celular , Relação Dose-Resposta à Radiação , Humanos , Transferência Linear de Energia/fisiologia , Doses de Radiação
8.
Neuroscience ; 112(2): 299-307, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12044448

RESUMO

We investigated the properties of glycine-induced responses in Cajal-Retzius cells, a neuronal cell type essential for the establishment of neocortical lamination. Whole-cell and gramicidin-perforated patch-clamp recordings were performed on visually identified Cajal-Retzius cells in tangential slices from neonatal rat cortex (postnatal days 0-3). With a pipette Cl(-) concentration of 50 mM, bath application of 1 mM glycine induced a membrane depolarization of 32.8+/-7.4 mV and a massive decrease in membrane resistance by 88+/-1.4%. The membrane depolarization was abolished in the presence of the glycinergic antagonists strychnine (30 microM) and phenylbenzene-omega-phosphono-alpha-amino acid (100 microM), while the GABA(A) receptor antagonist bicuculline (100 microM) and the glutamatergic antagonist (+/-)-2-amino-5-phosphonopentatonic acid (60 microM) were without effect, suggesting that the glycine-induced membrane responses were mediated exclusively by the strychnine-sensitive glycine receptor. The EC(50) for activation of glycine receptors was 0.54 mM, 1.62 mM and 2.41 mM, for the glycinergic agonists glycine, beta-alanine and taurine, respectively. Since the reversal potential of the glycine-induced currents showed a strong dependency on the intracellular chloride concentration and was virtually unaffected under HCO(3)(-)-free conditions, the activation of glycine receptors was probably linked to Cl(-) fluxes with little contribution of HCO(3)(-) ions. Perforated patch recordings from Cajal-Retzius cells demonstrated that glycine elicited depolarizing responses mediated by Cl(-) currents which reversed at -41+/-3.7 mV. In summary, from these results we suggest that Cajal-Retzius cells of the neonatal rat cerebral cortex express functional strychnine-sensitive glycine receptors that mediate depolarizing membrane responses via Cl(-) efflux.


Assuntos
Córtex Cerebral/metabolismo , Glicina/farmacologia , Neurônios/metabolismo , Animais , Animais Recém-Nascidos , Bicarbonatos/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Cloretos/metabolismo , Relação Dose-Resposta a Droga , Antagonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas GABAérgicos/farmacologia , Glicinérgicos/farmacologia , Gramicidina/farmacologia , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Receptores de Glicina/agonistas , Receptores de Glicina/antagonistas & inibidores , Receptores de Glicina/metabolismo , Taurina/farmacologia
9.
FEBS Lett ; 509(2): 235-8, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-11741595

RESUMO

Previously we showed that the expression of a Clostridium perfringens phospholipase C gene (plc) is activated by promoter upstream phased A-tracts in a low temperature-dependent manner. In this paper we characterize the interaction between the alpha subunit of C. perfringens RNA polymerase and the phased A-tracts. Hydroxyl radical footprinting and fluorescence polarization assaying revealed that the alpha subunit binds to the minor grooves of the phased A-tracts through its C-terminal domain with increased affinity at low temperature. The result provides a molecular mechanism underlying the activation of the plc promoter by the phased A-tracts.


Assuntos
DNA Bacteriano/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Regiões Promotoras Genéticas , Fosfolipases Tipo C/genética , Sequência de Bases , Sítios de Ligação , Clostridium perfringens , Genes Bacterianos , Dados de Sequência Molecular , Ligação Proteica , Subunidades Proteicas
10.
Toxicon ; 39(11): 1769-80, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11595639

RESUMO

Bacteria belonging to the genus Clostridium, both glycolytic and proteolytic, and both pathogenic and non-pathogenic, produce a battery of hydrolytic enzymes to obtain nutrients from various biopolymers. The clostridial hydrolytic enzymes are diverse, and are used or are potentially useful for fundamental and applied research purposes. Among them, enzymes degrading the major components in the extracellular matrix or on the cell surface in vertebrates are herein reviewed with special emphasis on recent knowledge gained through molecular biology of clostridial collagenases, sialidases and hyaluronidases. This paper also reviews some literature on the biotechnological approach to the designing of new molecular tools and drug delivery systems involving clostridial hydrolytic enzymes.


Assuntos
Clostridium/enzimologia , Colagenases/química , Hialuronoglucosaminidase/química , Neuraminidase/química , Animais , Clostridium/genética , Infecções por Clostridium/patologia , Colagenases/genética , Colagenases/metabolismo , Humanos , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Neuraminidase/genética , Neuraminidase/metabolismo , Relação Estrutura-Atividade
11.
Neuroscience ; 104(4): 933-46, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11457581

RESUMO

Cation-chloride cotransporters have been considered to play pivotal roles in controlling intracellular and extracellular ionic environments of neurons and hence controlling neuronal function. We investigated the total distributions of K-Cl cotransporter 1 (KCC1), KCC2 (KCC2), and Na-K-2Cl cotransporter 1 (NKCC1) messenger RNAs in the adult rat nervous system using in situ hybridization histochemistry. KCC2 messenger RNA was abundantly expressed in most neurons throughout the nervous system. However, we could not detect KCC2 messenger RNA expression in the dorsal root ganglion and mesencephalic trigeminal nucleus, where primary sensory neurons show depolarizing responses to GABA, suggesting that the absence of KCC2 is necessary for this phenomenon. Furthermore, KCC2 messenger RNA was also not detected in the dorsolateral part of the paraventricular nucleus, dorsomedial part of the suprachiasmatic nucleus, and ventromedial part of the supraoptic nucleus where vasopressin neurons exist, and in the reticular thalamic nucleus. As vasopressin neurons in the suprachiasmatic nucleus and neurons in the reticular thalamic nucleus produce their intrinsic rhythmicity, the lack of KCC2 messenger RNA expression in these regions might be involved in the genesis of rhythmicity through the control of intracellular chloride concentration. The expression levels of KCC1 and NKCC1 messenger RNAs were relatively low, however, positive neurons were observed in several regions, including the olfactory bulb, hippocampus, and in the granular layer of the cerebellum. In addition, positive signals were seen in the non-neuronal cells, such as choroid plexus epithelial cells, glial cells, and ependymal cells, suggesting that KCC1 and NKCC1 messenger RNAs were widely expressed in both neuronal and non-neuronal cells in the nervous system. These results clearly indicate a wide area- and cell-specific variation of cation chloride cotransporters, emphasizing the central role of anionic homeostasis in neuronal function and communication.


Assuntos
Proteínas de Transporte/genética , Expressão Gênica/fisiologia , Sistema Nervoso/metabolismo , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Simportadores , Animais , Cerebelo/citologia , Cerebelo/metabolismo , Plexo Corióideo/citologia , Plexo Corióideo/metabolismo , Diencéfalo/citologia , Diencéfalo/metabolismo , Epêndima/citologia , Epêndima/metabolismo , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Masculino , Mesencéfalo/citologia , Mesencéfalo/metabolismo , Sistema Nervoso/citologia , Neuroglia/citologia , Neuroglia/metabolismo , Neurônios/citologia , Ratos , Ratos Wistar , Rombencéfalo/citologia , Rombencéfalo/metabolismo , Simportadores de Cloreto de Sódio-Potássio , Telencéfalo/citologia , Telencéfalo/metabolismo , Cotransportadores de K e Cl-
12.
J Neurochem ; 77(5): 1185-97, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11389169

RESUMO

Sialic acids play important roles in various biological functions. In the brain, evidence suggests that sialylation of glycoproteins and glycolipids affects neural plasticity. While the 18 sialyltransferase isoenzymes (STs) identified to date synthesize individual sialyl-oligosaccharide structures, they each exhibit activity toward more than one substrate and can overlap in their specificity. Therefore, the distribution of STs is a secondary factor in the study of specific sialylation. Here, seven STs; ST3Gal I-IV, ST8Sia IV, ST6Gal I and ST6GalNAc II, the expressions of which were identified in the adult hippocampus by RT-PCR, showed diverse localization patterns in the hippocampus on in situ hybridization, suggesting that the individual cells expressed relevant STS: Furthermore, to assay activity-related changes in ST expression, we used amygdaloid-kindling among models of neural plasticity. Differential expression of the STs participating in the kindling, notably, up-regulation of ST3Gal IV and ST6GalNAc II mRNAs, and down-regulation of ST3Gal I and ST8Sia IV mRNAs, were observed in the hippocampus following kindled seizures. These results indicate that ST expressions are regulated by physiological activity and may play a role in neural plasticity.


Assuntos
Hipocampo/metabolismo , Isoenzimas/biossíntese , RNA Mensageiro/biossíntese , Convulsões/metabolismo , Sialiltransferases/biossíntese , Animais , Autorradiografia , Regulação Enzimológica da Expressão Gênica , Hipocampo/citologia , Hipocampo/enzimologia , Hibridização In Situ , Masculino , Camundongos , Neurônios/enzimologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Convulsões/enzimologia , Regulação para Cima
13.
Brain Res ; 901(1-2): 281-95, 2001 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-11368979

RESUMO

Amygdaloid kindling is a model of human temporal lobe epilepsy, in which excitability in limbic structures is permanently enhanced by repeated stimulations. We report here dendritic aberrations occurring in mice following kindled-seizures. Adult mice received a biphasic square wave pulse [495+/-25.5 (S.E.M.) microA 60 Hz, 200 micros duration, for 2 s] unilaterally in the basolateral amygdaloid complex once a day and mice with electrophysiologically and behaviorally verified seizures were used in the experiments. The hippocampus and amygdaloid complex contralateral to the lesions were observed by immunofluorescence histochemistry with a somatodendritic marker, microtubule-associated protein 2 (MAP2), showing that kindled-seizures caused hypertrophy of proximal dendrites in the granule cells of the dentate gyrus and in neurons of the amygdalohippocampal area. To further characterize the morphological changes of the dendrites, electron micrographic analysis was performed on the contralateral side. (1) In the granular layer of the dentate gyrus and the amygdalohippocampal area, kindled-seizures generated an increase in the number of dendrites containing polymerized microtubules and width of dendritic profiles showing the increase was in the range 0.2-3.0 and 0.2-1.4 microm, respectively. (2) In the granular layer, bundles between dendrites separated by the puncta adhaerentia increased. (3) In the granular layer, the seizure-induced dendritic aberration was more severe in the rostral than the caudal region. These results suggested that growth of dendrites with enriched-stable microtubules is part of the structural plasticity in response to seizure activity in specific areas of the adult brain.


Assuntos
Tonsila do Cerebelo/patologia , Dendritos/patologia , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Excitação Neurológica/patologia , Plasticidade Neuronal/fisiologia , Tonsila do Cerebelo/fisiopatologia , Tonsila do Cerebelo/ultraestrutura , Animais , Tamanho Celular/fisiologia , Dendritos/ultraestrutura , Giro Denteado/patologia , Giro Denteado/fisiopatologia , Giro Denteado/ultraestrutura , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/fisiopatologia , Imunofluorescência , Hipocampo/fisiopatologia , Hipocampo/ultraestrutura , Camundongos , Microscopia Eletrônica , Proteínas Associadas aos Microtúbulos/análise
14.
J Biol Chem ; 276(17): 13778-83, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11278924

RESUMO

Activation of Clostridium perfringens epsilon-protoxin by tryptic digestion is accompanied by removal of the 13 N-terminal and 22 C-terminal amino acid residues. In this study, we examined the toxicity of four constructs: an epsilon-protoxin derivative (PD), in which a factor Xa cleavage site was generated at the C-terminal trypsin-sensitive site; PD without the 13 N-terminal residues (DeltaN-PD); PD without the 23 C-terminal residues (DeltaC-PD); and PD without either the N- or C-terminal residues (DeltaNC-PD). A mouse lethality test showed that DeltaN-PD was inactive, as is PD, whereas DeltaC-PD and DeltaNC-PD were equally active. DeltaC-PD and DeltaNC-PD, but not the other constructs formed a large SDS-resistant complex in rat synaptosomal membranes as demonstrated by SDS-polyacrylamide gel electrophoresis. When DeltaNC-PD and DeltaC-PD, both labeled with (32)P and mixed in various ratios, were incubated with membranes, eight distinct high molecular weight bands corresponding to six heteropolymers and two homopolymers were detected on a SDS-polyacrylamide gel, indicating the active toxin forms a heptameric complex. These results indicate that C-terminal processing is responsible for activation of the toxin and that it is essential for its heptamerization within the membrane.


Assuntos
Toxinas Bacterianas/química , Toxinas Bacterianas/metabolismo , Membrana Celular/metabolismo , Peptídeos/metabolismo , Sinaptossomos/metabolismo , Sequência de Aminoácidos , Aminoácidos/química , Animais , Sítios de Ligação , Encéfalo/metabolismo , Linhagem Celular , Dicroísmo Circular , Cães , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Masculino , Camundongos , Dados de Sequência Molecular , Peptídeos/química , Fosforilação , Plasmídeos/metabolismo , Polímeros/química , Ligação Proteica , Dobramento de Proteína , Ratos
15.
Oncol Rep ; 8(2): 355-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11182055

RESUMO

The lack of an accurate system to predict the response to radiotherapy for individual cancer lesions remains a major clinical problem. The aim of this study was to establish whether heme oxygenase-1 (HO-1) may be useful in predicting radiosensitivity of esophageal cancers. We evaluated biopsy specimens from 13 esophageal squamous cell cancer patients. Of these, 8 patients had tumors responding to radiotherapy, and the remainder were considered radioresistant. Expression of HO-1 was assayed using a standard immunoperoxidase technique. Clinicopathological parameters were also analyzed as factors potentially contributing to radiosensitivity. Seven of 13 patients (53.8%) showed cytoplasmic staining for HO-1 in cancer tissues. The local treatment failure rate was 0% for HO-1 positive patients, as opposed to 83.3% for HO-1-negative patients (p=0.012). In contrast, tumor size, stage, and histologic grade were not significantly different between radiotherapy responders and non-responders to radiation therapy. No relationship was observed between HO-1 expression and clinicopathologic features. The results of the current study suggest that expression of HO-1 may be a useful indicator of radiosensitivity for esophageal cancer patients.


Assuntos
Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/radioterapia , Heme Oxigenase (Desciclizante)/análise , Fatores Etários , Idoso , Neoplasias Esofágicas/enzimologia , Heme Oxigenase-1 , Humanos , Imuno-Histoquímica , Proteínas de Membrana , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Falha de Tratamento
16.
Pancreas ; 22(1): 32-9, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11138968

RESUMO

We demonstrated that the dynamic aspects of cytokine production in rat acute pancreatitis, which was induced by cerulein and aggravated by subsequent lipopolysaccharide (LPS) injection. A priming effect by induction of mild pancreatitis with cerulein enhanced the subsequent cytokine production by LPS injection. Alternatively, after induction of severe pancreatitis with cerulein and LPS, cytokine production was markedly suppressed for > or = 90 hours. Production of interleukin-2 (IL-2) by splenocytes decreased, and mortality rate after cecal ligation and puncture (CLP) increased significantly after induction of severe acute pancreatitis. These results suggest that the suppression of a cytokine response in severe acute pancreatitis may alter the defense system and, as a result, increase mortality after CLP.


Assuntos
Citocinas/metabolismo , Endotoxemia/metabolismo , Pancreatite/metabolismo , Doença Aguda , Animais , Células Cultivadas , Ceruletídeo , Endotoxemia/complicações , Endotoxemia/mortalidade , Escherichia coli , Lipopolissacarídeos , Masculino , Pancreatite/etiologia , Pancreatite/mortalidade , Peritonite/metabolismo , Ratos , Ratos Wistar , Baço/citologia , Baço/metabolismo
17.
Connect Tissue Res ; 42(4): 281-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11913772

RESUMO

The substrate spectrum of the tandem collagen-binding domain (CBD) of Clostridium histolyticumclass I collagenase (ColG) was examined both in vitro and in vivo. CBD bound to insoluble type I, II, III and IV collagens in vitro, and to skin, aorta, tendon, kidney, trachea and corneal tissues containing various types of collagen fibrils or sheets. CBD bound to all kinds of collagen fibrils regardless of their diameters and also bound to sheet-forming collagen in the glomerular basal lamina or Descemet's membrane of the cornea. This wide substrate spectrum expands possible applications of the drug delivery system we proposed previously (PNAS 95:7018-7023, 1998). Therapeutic agents fused with CBD will bind not only to subcutaneous tissues, but also to other tissues containing non-type I collagen.


Assuntos
Colágeno/metabolismo , Colagenase Microbiana/genética , Colagenase Microbiana/metabolismo , Animais , Bovinos , Colágeno/química , Feminino , Humanos , Técnicas In Vitro , Microscopia Imunoeletrônica , Estrutura Terciária de Proteína/fisiologia , Especificidade por Substrato
18.
J Biol Chem ; 276(12): 8761-70, 2001 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-11121400

RESUMO

Clostridium histolyticum type I collagenase (ColG) has a segmental structure, S1+S2+S3a+S3b. S3a and S3b bound to insoluble collagen, but S2 did not, thus indicating that S3 forms a collagen-binding domain (CBD). Because S3a+S3b showed the most efficient binding to substrate, cooperative binding by both domains was suggested for the enzyme. Monomeric (S3b) and tandem (S3a+S3b) CBDs bound to atelocollagen, which contains only the collagenous region. However, they did not bind to telopeptides immobilized on Sepharose beads. These results suggested that the binding site(s) for the CBD is(are) present in the collagenous region. The CBD bound to immobilized collagenous peptides, (Pro-Hyp-Gly)(n) and (Pro-Pro-Gly)(n), only when n is large enough to allow the peptides to have a triple-helical conformation. They did not bind to various peptides with similar amino acid sequences or to gelatin, which lacks a triple-helical conformation. The CBD did not bind to immobilized Glc-Gal disaccharide, which is attached to the side chains of hydroxylysine residues in the collagenous region. These observations suggested that the CBD specifically recognizes the triple-helical conformation made by three polypeptide chains in the collagenous region.


Assuntos
Clostridium/enzimologia , Colágeno/metabolismo , Colagenases/metabolismo , Sequência de Bases , Colagenases/química , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Humanos , Especificidade por Substrato , Ressonância de Plasmônio de Superfície
19.
J Surg Res ; 94(2): 153-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11104655

RESUMO

BACKGROUND: Elastase activity in cancer cells has been reported to promote their metastasis. Hence, we analyzed the influence of elastase activity of cancer cells on their responsive adhesion to vascular endothelial cells. MATERIALS AND METHODS: Human pancreatic (S2-007, S2-013, S2-020, S2-028) and colonic (COLO205) cancer cell lines were used. S2-007, S2-013, and S2-020 possess high elastase activity, whereas S2-028 and COLO205 have low elastase activity. Adhesive reactions of these cancer cells and neutrophils to TNFalpha-activated HUVEC were analyzed. Bound cells onto HUVEC were counted after incubation for 10 min. The effects of suppression of elastase activity by ZD8321, a potent elastase inhibitor, and supplementation of human neutrophil elastase (NE) on the adhesive reactions were also analyzed. In addition, E-selectin expression on HUVEC and concentrations of soluble E-selectin in the medium were measured. RESULTS: Adhesion of cells with high intracellular elastase activity to TNFalpha-activated HUVEC was suppressed by ZD8321. On the other hand, adhesion of cells with low elastase activity was enhanced by exogenous NE. Expression of E-selectin, a key molecule in leukocyte-endothelial cell interaction, on HUVEC was increased by NE. Soluble E-selectin concentration in the medium increased after the adhesive reaction between neutrophils and HUVEC. This increase was thought to be due to the shedding of cell surface E-selectin. Such responses were inhibited by ZD8321. CONCLUSION: Elastase activity has a biological function of stimulating both the E-selectin expression on HUVEC and the resultant adhesive reaction of cancer cells with them. Inhibition of elastase activity is a potent strategy for controlling cancer metastasis.


Assuntos
Adesão Celular/fisiologia , Endotélio Vascular/fisiologia , Neutrófilos/fisiologia , Elastase Pancreática/metabolismo , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Neoplasias do Colo/enzimologia , Neoplasias do Colo/fisiopatologia , Meios de Cultura , Selectina E/análise , Endotélio Vascular/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Oligopeptídeos/farmacologia , Elastase Pancreática/antagonistas & inibidores , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/fisiopatologia , Polimixina B/farmacologia , Proteínas Recombinantes/farmacologia , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia , Veias Umbilicais
20.
Pancreas ; 21(4): 392-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11075994

RESUMO

We studied the effect of tumor necrosis factor alpha (TNFalpha), one of the major inflammatory cytokines, on the adhesive reaction of pancreatic cancer cells to human umbilical vein endothelial cells (HUVECs) and on the hepatic metastasis of cancer cells in vivo. After TNFalpha stimulation, the expression of E-selectin, an adhesion molecule to neutrophils on HUVECs, increased. In addition, the adhesion of pancreatic cancer cells to HUVECs increased after TNFalpha stimulation, as was observed with neutrophils. The TNFalpha-induced adhesive response depended on the extent of sialyl Lewis(a) expression on cancer cells. The hepatic metastasis in vivo was often observed when cancer cells expressing a high amount of sialyl Lewis(a) were inoculated intrasplenically after increase in plasma TNFalpha concentration by lipopolysaccharide administration. Because sialyl Lewis(a) on cancer cells is a ligand for E-selectin on HUVECs, as sialyl Lewis(x) on neutrophils, TNFalpha upregulated the adhesive interaction between sialyl Lewis(a) on cancer cells and E-selectin on HUVECs. These results suggest that production of TNFalpha after surgical trauma may stimulate the hematogenic metastasis of cancer cells with a high sialyl Lewis(a) expression.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Células Cultivadas , Selectina E/análise , Endotélio Vascular/citologia , Humanos , Lipopolissacarídeos/farmacologia , Neoplasias Hepáticas/secundário , Camundongos , Camundongos SCID , Neutrófilos/efeitos dos fármacos , Neutrófilos/fisiologia , Fator de Necrose Tumoral alfa/análise
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