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1.
Br J Surg ; 107(9): 1192-1198, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32335898

RESUMO

BACKGROUND: The right hepatic venous system consists of the right hepatic vein (RHV) and inferior RHVs (IRHVs). When the right posterior section is used as a graft for liver transplantation, understanding variations and relationships between the RHV and IRHVs is critical for graft venous return and hepatic vein reconstruction. This study aimed to evaluate variations in the hepatic veins and the relationships between them. METHODS: The medical records and CT images of patients who underwent hepatectomy as liver donors were assessed retrospectively. The relationship between the veins was evaluated by three-dimensional CT. RESULTS: The configuration of the posterior section was classified into one of eight types based on the RHV and IRHVs in 307 patients. Type 1a (103 of 307), type 1b (139 of 307) and type 2a (40 of 307) accounted for 91·9 per cent of the total. The diameter of the RHV extending towards the inferior vena cava had a significant inverse correlation with that of the IRHV (r2  = -0·615, P < 0·001). Type 1a, which had no IRHVs, had the RHV with the largest diameter; conversely, type 2a, which had a large IRHV, had the RHV with the smallest diameter. CONCLUSION: The hepatic venous system of the right posterior section was classified into eight types, with an inverse relationship between RHV and IRHV sizes. This information is useful for segment VII resection or when the right liver is used as a transplant graft.


ANTECEDENTES: El sistema venoso hepático derecho consiste en la vena hepática derecha (right hepatic vein, RHV) y las RHVs inferiores (IRHVs). Cuando se utiliza la sección posterior derecha hepática como injerto para el trasplante hepático, es fundamental conocer las variaciones e interrelaciones entre la RHV y las IRHVs para el retorno venoso del injerto y la reconstrucción de la vena hepática. El objetivo de este estudio fue determinar las variaciones en las venas hepáticas y sus interrelaciones. MÉTODOS: Se evaluaron retrospectivamente las historias clínicas y las imágenes de la tomografía computarizada de los pacientes que se sometieron a una hepatectomía como donantes vivos para trasplante hepático. La interrelación entre las venas se evaluó mediante imágenes de CT tridimensional. RESULTADOS: La configuración de la sección posterior clasificó a 307 pacientes en base a la RHV y a las IRHVs. Se clasificaron en 8 tipos, de los cuales el Tipo 1a (103/307), el Tipo 1b (139/307) y el Tipo 2a (40/307) representaron el 92% del total. El diámetro de la RHV que se extiende hacia la vena cava inferior presentó una correlación inversa significativa con la de las IRHV (r2: −0,632, P < 0,0001). El diámetro mayor de la RHV se observó en el Tipo 1a, que no presentaba IRHVs; por el contrario, el diámetro más pequeño se observó en el Tipo 2a que presentaba una IRHV grande. CONCLUSIÓN: El sistema venoso hepático de la sección posterior derecha se clasificó en 8 subtipos con una relación inversa entre los tamaños de la RHV y las IRHV. Esta información es útil cuando se practica una resección del segmento 7 o cuando se utiliza el hígado derecho como injerto para el trasplante.


Assuntos
Veias Hepáticas/diagnóstico por imagem , Doadores de Tecidos , Veias Hepáticas/anatomia & histologia , Veias Hepáticas/cirurgia , Humanos , Imageamento Tridimensional , Fígado/irrigação sanguínea , Transplante de Fígado/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
2.
Lett Appl Microbiol ; 53(2): 127-33, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21535049

RESUMO

AIMS: The aim of this study was to explore a new PCR target gene for Vibrio parahaemolyticus, based on the histone-like nucleoid structure (H-NS) gene. METHODS AND RESULTS: Primers for the H-NS gene were designed for specificity to V. parahaemolyticus and incorporated into a PCR assay. The PCR assay was able to specifically detect all of the 82 V. parahaemolyticus strains tested, but did not result in amplification in the 47 other Vibrio spp. and nonVibrio spp. strains. The detection limit of the PCR assay was 0.14 pg purified genomic DNA and 1.8 × 10(5) CFU g(-1) spiked oyster samples from V. parahaemolyticus RIMD2210633. Furthermore, a multiplex PCR assay targeting the hns, tdh and trh genes was successfully developed to detect virulent V. parahaemolyticus strains. CONCLUSIONS: The H-NS-based PCR assay developed in this study was sensitive and specific, with great potential for field detection of V. parahaemolyticus in seawater or seafood samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The H-NS gene was validated as a new specific marker gene in PCR assays for accurate detection and identification of V. parahaemolyticus, which has the potential to be applied in diagnostics and taxonomic studies.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Vibrio parahaemolyticus/genética , Animais , Técnicas de Tipagem Bacteriana , Sequência de Bases , Primers do DNA/genética , Dados de Sequência Molecular , Ostreidae/microbiologia , Reação em Cadeia da Polimerase/métodos , Alimentos Marinhos/microbiologia , Frutos do Mar/microbiologia , Vibrio/genética , Vibrio parahaemolyticus/classificação , Vibrio parahaemolyticus/isolamento & purificação
3.
Lett Appl Microbiol ; 51(3): 293-300, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20666989

RESUMO

AIMS: To develop an effective multiplex PCR for simultaneous and rapid detection of Vibrio cholerae, Vibrio vulnificus and Vibrio parahaemolyticus, the three most important Vibrio species that can cause devastating health hazards among human. METHODS AND RESULTS: Species-specific PCR primers were designed based on toxR gene for V. cholerae and V. parahaemolyticus, and vvhA gene for V. vulnificus. The multiplex PCR was validated with 488 Vibrio strains including 322 V. cholerae, 12 V. vulnificus, and 82 V. parahaemolyticus, 20 other Vibrio species and 17 other bacterial species associated with human diseases. It could detect the three target bacteria without any ambiguity even among closely related species. It showed good efficiency in detection of co-existing target species in the same sample. The detection limit of all the target species was ten cells per PCR tube. CONCLUSIONS: Specificity and sensitivity of the multiplex PCR is 100% each and sufficient for simultaneous detection of these potentially pathogenic Vibrio species in clinical and environmental samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This simple, rapid and cost-effective method can be applicable in a prediction system to prevent disease outbreak by these Vibrio species and can be considered as an effective tool for both epidemiologist and ecologist.


Assuntos
Técnicas Bacteriológicas/métodos , Reação em Cadeia da Polimerase/métodos , Vibrioses/diagnóstico , Vibrio cholerae/isolamento & purificação , Vibrio parahaemolyticus/isolamento & purificação , Vibrio vulnificus/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Humanos , Sensibilidade e Especificidade , Fatores de Transcrição/genética , Vibrio cholerae/genética , Vibrio parahaemolyticus/genética , Vibrio vulnificus/genética
4.
Lett Appl Microbiol ; 50(2): 146-52, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19943887

RESUMO

AIM: To develop a haemolysin (hly) gene-based species-specific multiplex PCR for simple and rapid detection of Vibrio campbellii, V. harveyi and V. parahaemolyticus. METHODS AND RESULTS: The complete hly genes of three V. campbellii strains isolated from diseased shrimps were sequenced and species-specific PCR primers were designed based on these sequences and the registered hly gene sequences of Vibrio harveyi and Vibrio parahaemolyticus. Specificity and sensitivity of the multiplex PCR was validated with 27 V. campbellii, 16 V. harveyi, and 69 V. parahaemolyticus, 18 other Vibrio species, one Photobacterium damselae and nine other bacterial species. The detection limits of all the three target species were in between 10 and 100 cells per PCR tube. CONCLUSIONS: Specificity and sensitivity of the multiplex PCR is 100% each and sufficient to be considered as an effective tool in a prediction system to prevent potential disease outbreak by these Vibrio species. SIGNIFICANCE AND IMPACT OF THE STUDY: Because there is lack of simple, rapid and cost-effective method to differentiate these closely related V. campbellii, V. harveyi and V. parahaemolyticus species, the multiplex PCR developed in this study will be very effective in epidemiological, ecological and economical points of view.


Assuntos
Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana/métodos , Proteínas Hemolisinas/genética , Reação em Cadeia da Polimerase/métodos , Vibrio parahaemolyticus/isolamento & purificação , Animais , Penaeidae , Reação em Cadeia da Polimerase/economia , Sensibilidade e Especificidade , Vibrio/genética , Vibrio/isolamento & purificação , Vibrioses/diagnóstico , Vibrioses/microbiologia , Vibrio parahaemolyticus/genética
5.
J Natl Cancer Inst ; 55(4): 925-30, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1185810

RESUMO

Changes in the isozymes of pepsinogen (Pg) separated from the glandular stomachs of rats were studied by polyacrylamide gel electrophoresis during carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), from the beginning of MNNG administration to 3 months after the end of its 7-month regimen. In 13 of 25 rats killed successively, one (Pg 1) of the three pepsinogen isozymes (Pg 1, 3, 4) normally present in the pyloric mucosa had decreased or disappeared. It decreas was observed from 1 week after the beginning of MNNG treatment to at least 3 months after the end of the 7-month MNNG administration. Remarkable histopathologic changes were found from 8 months after MNNG was given, and rats showing such unusual histopathologic alterations also had changes in their pepsinogen isozyme pattern. In 4 of 27 rats, two (Pg 1, 2) of the four isozymes of pepsinogen (Pg 1-4) in the fundic mucosa decreased or disappeared from 3 months after the beginning of MNNG treatment to at least 2 months after the end of its 7-month administration. Histopathologic changes induced by MNNG were not as remarkable in the fundic mucosa as in the pyloric mucosa.


Assuntos
Adenocarcinoma/metabolismo , Pepsinogênios/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/patologia , Animais , Mucosa Gástrica/metabolismo , Masculino , Metilnitronitrosoguanidina , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Piloro/metabolismo , Ratos , Neoplasias Gástricas/induzido quimicamente , Neoplasias Gástricas/patologia
6.
J Natl Cancer Inst ; 56(3): 615-21, 1976 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-768504

RESUMO

Twenty-eight cases of spontaneous colon tumors were found during autopsy of approximately 3,000 male W rats in our laboratories between 1968 and 1974. Macroscopically, these tumors were multiple and localized in the proximal part of the colon. Many nodules protruded on the serosal surface; polypoid tumors protruding into the lumen were rare. Microscopically, hyperplastic and adenomatous polyps were observed in the mucous membrane of the colon. There was adenomatous downward growth into the submucosal layer, and tubular-type adenocarcinomas invaded all the coats of the colon wall. Structural atypism was frequent and slight cell atypism was also present. Invasive tumors sometimes had an inflammatory reaction, and bacterial growth was observed within the neoplastic glands in thionine-stained sections. Escherichia coli and a gram-negative, facultative anaerobic bacillus, which grew only with E. coli in vitro, were isolated. A cultured epithelial cell line was established from one colon tumor. After a primary tumor was transplanted intraperitoneally into young adult rats, a mass grew in the peritoneal cavity for 4 months. The tumor incidence seemed higher at different times in the animals examined.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/veterinária , Neoplasias do Colo/veterinária , Doenças dos Roedores/patologia , Fatores Etários , Animais , Animais de Laboratório , Neoplasias do Colo/microbiologia , Escherichia coli/isolamento & purificação , Masculino , Transplante de Neoplasias , Ratos , Transplante Homólogo
7.
Biochim Biophys Acta ; 1260(3): 365-8, 1995 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-7873617

RESUMO

In a previous study, we found that the steady state transcript level of type II hexokinase was specifically and remarkably elevated in rat hepatoma AH130 cells. To determine the molecular mechanism of transcriptional control of the type II hexokinase gene, we examined the nucleotide sequence of its 5'-flanking region and analyzed putative transcription factor binding sites. We also examined the type II hexokinase promoter activity by the chloramphenicol acetyltransferase (CAT) assay.


Assuntos
Hexoquinase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Cloranfenicol O-Acetiltransferase/genética , Clonagem Molecular , DNA , Hexoquinase/química , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Ratos , Transcrição Gênica
8.
Biochim Biophys Acta ; 1329(1): 174-82, 1997 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-9370255

RESUMO

Membrane proteins, such as viral spike, were transferred spontaneously from influenza virus-infected cells to various liposomes. The protein transfer was enhanced by the presence of negative charged component dicetylphosphate (DCP) or stearic acid (SA) in dimyristoylphosphatidylcholine (DMPC) liposomes. The lowering of membrane fluidity did not relate to the effect of DCP or SA on protein transfer in this study. We considered that the alteration of membrane properties, such as construction of the surface or stability of transferred protein in liposomes, due to the specific structure of DCP or SA is responsible for the enhancement of spontaneous protein transfer by the presence of the amphiphilic components.


Assuntos
Lipossomos/metabolismo , Organofosfatos/farmacologia , Orthomyxoviridae/metabolismo , Ácidos Esteáricos/farmacologia , Proteínas da Matriz Viral/metabolismo , Animais , Linhagem Celular , Dimiristoilfosfatidilcolina/metabolismo , Difenilexatrieno/metabolismo , Eletrofisiologia , Polarização de Fluorescência , Corantes Fluorescentes/metabolismo , Fluorometria , Haplorrinos , Rim/virologia , Fluidez de Membrana/efeitos dos fármacos
9.
Biochim Biophys Acta ; 1426(1): 133-42, 1999 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-9878710

RESUMO

The bisbenzylisoquinoline alkaloid cepharanthine, which has been considered to exhibit antiperoxidation activity due to its membrane stabilizing effect, was found to scavenge radicals such as .OH and DPPH (1,1-diphenyl-2-picrylhydrazyl) in solution, and to inhibit lipid peroxidation in mitochondria and liposomes by Fe2+/ADP. The antiperoxidation activity of cepharanthine in rat liver mitochondria initiated by Fe2+/ADP at pH 7.4 was much greater than that of alpha-tocopherol, its half-inhibitory concentration being about 23 microM. However, cepharanthine was effective only at neutral pH values such as pH 7.4, not in a moderately acidic pH region below pH 6.5. Accordingly, the neutral form of the deprotonated amine moiety in the tetrahydroisoquinoline ring is concluded to be responsible for the radical scavenging activity of cepharanthine. There are two amine moieties in the cepharanthine molecule, but we specified the effective amine moiety from the antiperoxidation activities of the imine analogs of cepharanthine.


Assuntos
Alcaloides/farmacologia , Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Picratos , Alcaloides/química , Aminas/análise , Animais , Benzilisoquinolinas , Bepridil/análogos & derivados , Bepridil/química , Compostos de Bifenilo , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Fluidez de Membrana/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Ratos , Ratos Wistar
10.
Biochim Biophys Acta ; 1528(1): 25-30, 2001 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11514094

RESUMO

We investigated the mechanism of cell toxicity of alpha-tocopheryl hemisuccinate (TS). TS concentration- and time-dependently induced the lactate dehydrogenase release and DNA fragmentation of rat vascular smooth muscle cells (VSMC). Exogenous addition of superoxide dismutase, but not catalase, significantly inhibited the cell toxicity of TS. The NADPH-dependent oxidase activity of VSMC was stimulated by TS treatment. The cell toxicity of TS was inhibited by NADPH oxidase inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride. Consequently, TS-induced apoptosis of VSMC was suggested to be caused by exogenous O(2)(-) generated via the oxidase system activated with TS.


Assuntos
Apoptose , Músculo Liso Vascular/efeitos dos fármacos , Superóxidos/metabolismo , Vitamina E/análogos & derivados , Vitamina E/toxicidade , Animais , Ácido Ascórbico , Catalase , Células Cultivadas , Grupo dos Citocromos c/química , Fragmentação do DNA , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , L-Lactato Desidrogenase/análise , Músculo Liso Vascular/enzimologia , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Oxigênio/análise , Ratos , Superóxido Dismutase , Superóxidos/análise , Tocoferóis , Vitamina E/antagonistas & inibidores , Vitamina E/química
11.
Biochim Biophys Acta ; 1512(2): 251-8, 2001 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-11406102

RESUMO

The effects of the carotenoids beta-carotene and astaxanthin on the peroxidation of liposomes induced by ADP and Fe(2+) were examined. Both compounds inhibited production of lipid peroxides, astaxanthin being about 2-fold more effective than beta-carotene. The difference in the modes of destruction of the conjugated polyene chain between beta-carotene and astaxanthin suggested that the conjugated polyene moiety and terminal ring moieties of the more potent astaxanthin trapped radicals in the membrane and both at the membrane surface and in the membrane, respectively, whereas only the conjugated polyene chain of beta-carotene was responsible for radical trapping near the membrane surface and in the interior of the membrane. The efficient antioxidant activity of astaxanthin is suggested to be due to the unique structure of the terminal ring moiety.


Assuntos
Difosfato de Adenosina/química , Antioxidantes/química , Cardiolipinas/química , Ferro/química , Peroxidação de Lipídeos , Lipossomos/química , Fosfatidilcolinas/química , beta Caroteno/análogos & derivados , beta Caroteno/química , Compostos Ferrosos/química , Radicais Livres/química , Ligação de Hidrogênio , Cinética , Modelos Moleculares , Conformação Molecular , Oxirredução , Propriedades de Superfície , Xantofilas , Zeaxantinas
12.
Curr Opin Biotechnol ; 9(3): 278-82, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9650273

RESUMO

Some marine bacteria have a special energy-transducing mechanism that is different from those found in Escherichia coli or most of the freshwater and terrestrial bacteria. These marine bacteria specifically require Na+ for their growth and utilize a Na+ circuit for various cellular functions. So far, three types of primary Na+ pump have been identified (i.e. respiration-dependent, decarboxylase-driven and Na+ ATP synthase). Among them, the first type of Na+ pump plays the major role in the marine environment. Recently, the gene sequence and distribution of this Na+ pump have been clarified. In addition, information on genetics and the ecological significance of Na+ driven flagellar motors has also been accumulating. This recent progress in the research of the 'Na+ world' is revealing an interesting way of life that is unique to marine microorganisms.


Assuntos
Bactérias/metabolismo , Metabolismo Energético , ATPase Trocadora de Sódio-Potássio/metabolismo , Alcaligenes/metabolismo , Fenômenos Fisiológicos Bacterianos , Movimento Celular , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Consumo de Oxigênio , Pseudomonas/metabolismo , Água do Mar , Vibrio/metabolismo , Microbiologia da Água
13.
J Cereb Blood Flow Metab ; 8(4): 568-74, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2839528

RESUMO

Opioid ([3H]naloxone) and spirodecanone ([3H]spiperone) binding sites in the hippocampus were visualized in the Mongolian gerbil and in the rat using in vitro autoradiography. In the hippocampus, marked differences were noted in the stratum (sr.) pyramidale of the CA1 subfield where opioid and spirodecanone (assayed in the presence of mianserin and sulpiride) binding activities were very low in gerbils, but high in rats. Gerbils exhibited a high concentration of [3H]naloxone binding sites in the sr. pyramidale of the CA3 subfield, as observed in the rat. In addition, the gerbil has a very high opioid receptor density in the hilar region and in the sr. moleculare of the dentate gyrus. The cellular localization of opioid and spirodecanone receptor sites was studied in the rat hippocampus using selective neuronal damage to CA1 and CA3 neurons by means of ischemia and kainic acid treatment, respectively. The results suggest that the gerbil differs from the rat with respect to the characteristic pyramidal cells (spirodecanone binding site) and interneurons (opioid receptor) in the CA1 subfield of the hippocampus. Distinct localization of opioid and spirodecanone receptors in the gerbil provides a good model with which to investigate the electrophysiological and biochemical roles of opioid peptides and butyrophenone spirodecanone drugs.


Assuntos
Gerbillinae/metabolismo , Ratos/metabolismo , Receptores Dopaminérgicos/metabolismo , Receptores Opioides/metabolismo , Animais , Autorradiografia , Sítios de Ligação , Feminino , Masculino , Compostos de Espiro/metabolismo
14.
J Cereb Blood Flow Metab ; 11(6): 974-8, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1939390

RESUMO

We examined the brain damage following repeated hypotensive episodes in the rat. Severe hypotension was induced by withdrawal of arterial blood. The MABP was maintained at about 25 mm Hg with isoelectric EEG and the shed blood was retransfused. After 1 week of recovery, histopathological changes were examined. No brain damage was observed after 1 min of isoelectric EEG. Mild neuronal damage to the hippocampal CA1 subfield was seen in some animals after two episodes of 1-min isoelectric EEG at a 1-h interval. Significant and consistent neuronal loss in the hippocampal CA1 subfield was observed after three episodes of 1-min isoelectric EEG. Scattered neuronal damage in the thalamus was additionally seen in some animals. The present study indicates that repeated brief hypotensive episodes produce brain damage depending on the number of episodes, even though no brain damage results when induced as a single insult. This animal model may reproduce hemodynamic transient ischemic attacks in humans.


Assuntos
Hipocampo/patologia , Hipotensão/patologia , Animais , Contagem de Células , Morte Celular , Eletroencefalografia , Hipotensão/fisiopatologia , Masculino , Neurônios/patologia , Ratos , Ratos Endogâmicos , Fatores de Tempo
15.
J Cereb Blood Flow Metab ; 7(1): 82-8, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3027112

RESUMO

Quantitative receptor autoradiography was used to measure the binding of gamma-aminobutyric acid (GABA) and benzodiazepine receptors after ischemia by means of transient occlusion of bilateral common carotid arteries in the gerbil. [3H]Muscimol was used to label the GABAA receptors and [3H]flunitrazepam to label central type benzodiazepine receptors. In the superolateral convexities of the frontal cortices, [3H]muscimol binding was increased in 60% of the animals killed 3 days after ischemia, and decreased in 67% of the animals killed 27 days after ischemia. Twenty-seven days after ischemia, [3H]flunitrazepam binding in the substantia nigra pars reticulata increased to 252% of the control, though the increase in [3H]muscimol binding was not significant. In the dorsolateral region of the caudate putamen, marked neuronal necrosis and depletion of both [3H]muscimol and [3H]flunitrazepam binding sites were observed 27 days after ischemia, the ventromedial region being left intact. In spite of the depletion of pyramidal cells in the CA1 region of the hippocampus, both [3H]muscimol and [3H]flunitrazepam binding sites were preserved 27 days after ischemia. Since our previous study revealed that adenosine A1 binding sites were depleted in the CA1 subfield of the hippocampus after ischemia correlating with neuronal damage, GABAA and benzodiazepine receptors may not be distributed predominantly on the pyramidal cells in the CA1 region.


Assuntos
Química Encefálica , Ataque Isquêmico Transitório/metabolismo , Receptores de GABA-A/análise , Animais , Autorradiografia , Flunitrazepam/metabolismo , Gerbillinae , Hipocampo/patologia , Ataque Isquêmico Transitório/patologia , Muscimol/metabolismo , Trítio
16.
J Cereb Blood Flow Metab ; 9(5): 623-8, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2550493

RESUMO

The influence of transient forebrain ischemia on the temporal alteration of glutamate receptors in the hippocampal formation was analyzed by means of in vitro quantitative receptor autoradiography. We compared the binding of N-methyl-D-aspartate (NMDA) receptors using [3H]3-[+/-)2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), noncompetitive NMDA antagonist binding sites using [3H]N-(1-(2-thienyl)-cyclohexyl)-3,4-piperidine (TCP), and kainate (KA) receptors. In the CA1 subfield of the hippocampus, the number of NMDA receptors and noncompetitive NMDA antagonist binding sites remained constant during the early stage of recirculation when the CA1 pyramidal cells remained histologically intact. A significant reduction of these receptor densities was observed 7 days following ischemia, when NMDA receptors and noncompetitive NMDA antagonist binding sites lost 64 and 29% of their binding sites in the stratum radiatum of the CA1, respectively. The KA receptor density in the CA1 subfield decreased by 44% 7 days after ischemia. Marked loss of the above-mentioned receptors in the CA1 after selective depletion of the CA1 pyramidal cells indicated that NMDA receptors, noncompetitive NMDA antagonist binding sites, and KA receptors in the CA1 are predominantly localized on the CA1 pyramidal cells. NMDA receptor density in the CA3 gradually decreased during the recirculation period. The stratum moleculare of the dentate gyrus, whose structure was histologically intact after ischemic insult, also showed a reduction of NMDA receptors 7 days following ischemia. [3H]KA receptor density in the stratum lucidum of the CA3 and in the hilus also decreased during recirculation. These


Assuntos
Aminoácidos/metabolismo , Isquemia Encefálica/metabolismo , Hipocampo/metabolismo , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/antagonistas & inibidores , Sítios de Ligação , Diencéfalo/irrigação sanguínea , Masculino , N-Metilaspartato , Ratos , Ratos Endogâmicos , Receptores de Ácido Caínico , Receptores de N-Metil-D-Aspartato , Receptores de Neurotransmissores/metabolismo , Telencéfalo/irrigação sanguínea
17.
J Cereb Blood Flow Metab ; 8(3): 436-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2966804

RESUMO

The effect of PN200-110, a novel calcium antagonist, on the formation of brain edema was examined with rats using a middle cerebral artery (MCA) occlusion model. PN200-110 was effective in preventing the formation of brain edema in 6-h ischemia and in 3-h reperfusion following 3-h ischemia, which were cases in which great accumulations of calcium were autoradiographically observed. Furthermore, PN200-110 diminished the excessive accumulation of calcium in the MCA area involved. These results indicate that an inhibition of the massive influx of calcium into brain cells by PN200-110 may partially ameliorate cell damage, resulting in prevention of brain edema.


Assuntos
Edema Encefálico/prevenção & controle , Isquemia Encefálica/complicações , Bloqueadores dos Canais de Cálcio/uso terapêutico , Oxidiazóis/uso terapêutico , Animais , Autorradiografia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Cálcio/metabolismo , Isradipino
18.
J Cereb Blood Flow Metab ; 10(2): 207-12, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2303536

RESUMO

A new shock model in the rat using hemorrhagic hypotension for production of brain damage is described. Hemorrhagic shock was induced by lowering arterial blood pressure with bleeding. The MABP was maintained at approximately 25 mm Hg, accompanied by isoelectric EEG, and then shed blood was retransfused. At 1 week of recovery, morphological and 45Ca autoradiographic changes were examined. No brain damage was observed in rats after 1 min of isoelectric EEG. Mild neuronal damage in the hippocampal CA1 subfield was seen in some animals after 2 min of isoelectric EEG. Severe and consistent neuronal loss in the hippocampal CA1 subfield was recognized after 3 min of isoelectric EEG. Additional damage was also seen in the dentate hilus and the thalamus in some animals. This model can be used to study the pathophysiology of postshock brain damage and to assess new therapies following shock.


Assuntos
Encéfalo/fisiopatologia , Choque Hemorrágico/fisiopatologia , Animais , Autorradiografia , Pressão Sanguínea/fisiologia , Encéfalo/metabolismo , Encéfalo/patologia , Radioisótopos de Cálcio , Modelos Animais de Doenças , Eletroencefalografia , Masculino , Ratos , Ratos Endogâmicos , Choque Hemorrágico/metabolismo , Choque Hemorrágico/patologia
19.
J Cereb Blood Flow Metab ; 13(5): 773-80, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8395536

RESUMO

Hippocampal CA1 neurons are the most vulnerable to transient cerebral ischemia. However, the mechanism has not been fully understood. The level of mRNA for cytochrome C oxidase (COX) subunit I (COX-I), which is encoded by mitochondrial (mt) DNA, progressively decreased in the hippocampal CA1 neurons of gerbils from 3 h of reperfusion after 3.5 min of transient forebrain ischemia and completely disappeared at 7 days. The activity of COX protein also showed an early decrease in CA1 cells and was followed by reduction of the level of COX-I DNA after 2 days. However, succinic dehydrogenase, an mt enzyme encoded by nuclear DNA, maintained normal activity until 1 day in the CA1 cells and significantly decreased at 7 days. The mRNA for mt heat shock protein (HSP) 60 began to increase at 3 h in the CA1 cells and was sustained until 1 day. The mRNAs for 72-kDa heat shock protein and 73-kDa heat shock cognate protein, which are located mainly in the cytoplasm, were induced together in the CA1 cells with a peak at 1-2 days. These results suggest that a disturbance of mt DNA expression occurred in the CA1 neurons at the early stage of reperfusion and was aggravated over the course of time. The disturbance could cause progressive failure of energy production of the cells that eventually results in neuronal cell death.


Assuntos
DNA Mitocondrial/metabolismo , Expressão Gênica , Proteínas de Choque Térmico/genética , Hipocampo/metabolismo , Hipocampo/fisiologia , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/metabolismo , Animais , Northern Blotting , Southern Blotting , Densitometria , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Gerbillinae , Histocitoquímica , Hibridização In Situ , Masculino , Sondas Moleculares , RNA Mensageiro/metabolismo , Succinato Desidrogenase/metabolismo
20.
J Cereb Blood Flow Metab ; 13(5): 781-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8360284

RESUMO

To evaluate the mechanism of tolerance to ischemia, inductions of heat shock protein (HSP) 70 and heat shock cognate protein (HSC) 70 mRNAs in gerbil hippocampus were compared with in situ hybridization between cases of a single 3.5-min period of forebrain ischemia and a 3.5-min period of ischemia 2 days after 2-min pretreatment with ischemia. Immunohistochemistry for HSP70 protein and morphological studies were also performed in the same brains up to 7 days after the reperfusion. Following a single 3.5-min period of ischemia, HSP70 and HSC70 mRNAs were induced in all hippocampal cells. However, the hippocampal CA1 cells produced only a minimum of HSP70 protein, and the cells were almost lost by 7 days. Following 3.5 min of ischemia after 2-min pretreatment, large populations of the CA1 cells survived at 7 days. The peak time of the HSP70 and HSC70 mRNA induction shifted to an earlier period of reperfusion in all hippocampal cells as compared with the case of a single episode of ischemia. The peak of HSP70 and HSC70 mRNA induction shifted from 1 day to 3 h in the CA1 cells. The CA1 cells produced strongly immunoreactive HSP70 from 3 hr to 2 days. These results suggest that pretreatment with an initial period of ischemia (for 2 min) accelerated HSP70 and HSC70 gene expression at the transcriptional level, ameliorated the translational disturbance of HSP70 mRNA to protein, and saved the CA1 cells from subsequent lethal ischemia (for 3.5 min). These changes of heat shock gene expression might play important roles in the acquisition of ischemic tolerance of hippocampal CA1 neurons.


Assuntos
Expressão Gênica , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico/genética , Hipocampo/fisiopatologia , Ataque Isquêmico Transitório/genética , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Choque Térmico HSC70 , Proteínas de Choque Térmico/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Técnicas Imunológicas , Hibridização In Situ , Ataque Isquêmico Transitório/metabolismo , Ataque Isquêmico Transitório/patologia , Masculino , RNA Mensageiro/metabolismo , Recidiva
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