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1.
Neuroscience ; 136(1): 269-79, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16181739

RESUMO

To determine factors that contribute to the learning deficits observed in individuals with fetal alcohol syndrome, we examined the effects of early postnatal ethanol exposure on forms of synaptic plasticity thought to underlie memory. Treatment of rat pups with ethanol on postnatal day 7 impaired the induction of N-methyl-D-aspartate receptor-dependent long-term potentiation and abolished homosynaptic long-term depression in the CA1 region of hippocampal slices prepared at postnatal day 30. An N-methyl-D-aspartate receptor-independent form of long-term potentiation induced by very high frequency stimulation could be induced in slices from ethanol-treated rats. Defects in long-term depression correlated with a diminished contribution of ifenprodil-sensitive N-methyl-D-aspartate receptors to synaptic transmission and defects in a spontaneous alternation behavioral task. Rats exposed to ethanol on postnatal day 7 also exhibited diminished sensitivity of synaptic N-methyl-D-aspartate receptors to block by ethanol at postnatal day 30 and decreased behavioral sedation to systemic ethanol injections. These results indicate that changes in synaptic plasticity and N-methyl-D-aspartate receptor function are likely to provide a neural substrate for the cognitive and behavioral changes that follow developmental ethanol exposure.


Assuntos
Animais Recém-Nascidos/fisiologia , Etanol/administração & dosagem , Plasticidade Neuronal/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/fisiologia , Sinapses/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Comportamento Animal/efeitos dos fármacos , Esquema de Medicação , Resistência a Medicamentos , Etanol/antagonistas & inibidores , Etanol/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Hipnóticos e Sedativos/antagonistas & inibidores , Injeções Subcutâneas , Aprendizagem/efeitos dos fármacos , Piperidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
2.
Int J Occup Med Environ Health ; 12(2): 123-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10465902

RESUMO

A test to sterilize pieces of cloths, which are the material of hospital white coats (doctors and nurses wears), by microwave irradiation in place of autoclaving was done using a commercial 2,450 MHz microwave oven. When pieces of cloths made of cotton (35%) and polyester (65%) were contaminated experimentally with Escherichia coli or Staphylococcus aureus and irradiated by microwave, the bacteria were killed quite rapidly according to almost first-order reaction kinetics. Only after a 20-sec irradiation, when the water content of cloths was decreased from the original 48% to 35%, the relative survivals of these bacteria fell to below 1% that of the non-irradiated control. The cloths were neither browned nor crisped, even after a 10-min irradiation of microwaves.


Assuntos
Vestuário , Escherichia coli/efeitos da radiação , Micro-Ondas , Staphylococcus aureus/efeitos da radiação , Esterilização/métodos , Gossypium , Poliésteres
3.
J Colloid Interface Sci ; 187(2): 435-42, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9073417

RESUMO

Micelle formation was studied for four mixing combinations of dodecylammonium (DA) salts having perfluorocarboxylate ions (trifluoroacetate (PA) and pentafluoropropionate (PP) and alkane sulfonate ions (methane sulfonate (MS) and ethane sulfonate (ES)) as their counterions, i.e., DAPA/DAMS, DAPA/DAES, DAPP/DAMS, and DAPP/DAES. The fluorocarbon anions as counterions exhibited that the degree of counterion binding to micelle (beta) as well as the extent of stabilizing micelles and lowering ability of critical micellization concentration (CMC) are greater than hydrocarbon anions. The "mixed micelle formation" was examined in terms of CMC as a function of mole fraction (Xi) in each surfactant mixture. The CMCs of the mixed surfactant systems studied here, correspond to those of "surfactant with mixed counterions". However, by regarding tentatively those combinations as binary mixed surfactant systems, the CMC vs Xi curves (singly dispersed phase curves) as well as CMC vs micellar composition (Yi) curves (micellar phase curves) were simulated by applying the present authors' and Rubingh's equations which have been derived respectively with and without taking into account mutual added-salt effect (or the beta value for each pure system). A negative deviation from ideal mixing was observed for each combination, indicating that mixing of fluorocarbon anion with hydrocarbon anion as counterion of DA salts results in more stabilized micelle formation. Plotting the derivative of specific conductance (kappa) by total concentration of surfactant (Ct), dkappa/dCt against Ct, the curves showed a constant value at the sufficiently higher concentration range than CMC, and the constant values were found able to be related to the degree of dissociation of micelles (alpha). Even for the mixed systems, the alpha or beta values were estimated from the conductivity data. The greater power to stabilize micelle formation by fluorocarbon ions was interpreted on the basis of concept of "contact hydrophobic interaction" proposed by Mukerjee (Mukerjee, P., Colloids Surf. A: Physicochem. Eng. Aspects 84, 49 (1994)).

4.
Biosci Biotechnol Biochem ; 60(5): 889-90, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27281150

RESUMO

Squash glutamate decarboxylase was purified by DEAE-Cellulose batchwise followed by Blue-Sepharose, Cellulofine GCL-2000, and Toyopearl HW-55F column chromatography. The purified glutamate decarboxylase had a high specific activity (95.0 u/mg). The absorption spectrum of glutamate decarboxylase had an absorption maximum at 420 nm in the range 300-500 nm. A pH change from 5.3 to 7.8 was accompanied by a decrease in absorbancy at 420 nm. One mole of glutamate decarboxylase contained 3.8 and 1.3 mol of pyridoxal 5'-phosphate at pH 5.8 and pH 7.8, respectively.

5.
Microbiol Immunol ; 39(8): 571-6, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7494495

RESUMO

The effect of microwave irradiation on the survival of bacteriophage PL-1, which is specific for Lactobacillus casei, was studied using a commercial 2,450 MHz microwave oven. The phages were inactivated by microwave irradiation according to almost first-order reaction kinetics. The rate of phage inactivation was not affected by the difference in the continuous or intermittent irradiation, nor by the concentrations of phages used, but was affected by the volume of phage suspensions, which prevented the loss of generated heat. Microwave irradiation of phage suspensions produced a number of ghost phages with empty heads, but fragmentation of the tail was hardly noticed. The breakage of phage genome DNA was primarily caused by the heat generated by microwave irradiation, whereas the phage DNA was not affected by the same temperature achieved by heat from outside. Thus we concluded that the phage-inactivating effect of microwave irradiation was mainly attributed to a thermal microwave effect, which was much stronger than a simple thermal exposure.


Assuntos
Bacteriófagos/efeitos da radiação , Lactobacillus/virologia , Bacteriófagos/ultraestrutura , Dano ao DNA , DNA Viral/metabolismo , DNA Viral/efeitos da radiação , Micro-Ondas
6.
Gan To Kagaku Ryoho ; 19(10 Suppl): 1738-41, 1992 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-1530345

RESUMO

At our clinic for peritoneal dissemination cases of gynecological malignant tumors, we have been using intraperitoneal administration (ip) of anticancer agents such as CDDP with favorable results. However, since CDDP cannot be used for patients with renal dysfunction, we have administered CBDCA ip, and along with determining drug concentration, we also studied therapeutic effects. At the time of laparotomy in 5 cases of malignant tumors (ovarian cancer 4 cases, oviduct cancer 1 case), we subcutaneously implanted a reservoir port for the peritoneum in the upper inguinal region. Through this completely open port we administered by natural dripping 200-450 mg/body of CBDCA dissolved abdominal fluid and peripheral venous blood, and we determined the concentrations of total and free platinum. The ip concentration of platinum reached a peak of 142-19.8 micrograms/ml immediately after administration, and then gradually declined; at 8 hours it became 20.1-2.23 micrograms/ml, and was still detectable at 48 hours. In the peripheral venous blood peaked at 2 hours at 4.78-1.2 micrograms/ml, and was still observed at 48 hours. One 84-year-old patient with stage III oviduct cancer and renal dysfunction showed a marked reduction in ascites and improvement in PS from 4 to 1, so she is being treated on an outpatient basis. The efficacy rate was 60.0% with 2 CR and 1PR. Repeated ip administration of CBDCA was possible even in cases with renal damage rather than CDDP, but the side effects on the blood were severe. CBDCA ip achieves an effective level of free platinum in both the peritoneum administration methods for treating peritoneal disseminated cases.


Assuntos
Carboplatina/administração & dosagem , Neoplasias das Tubas Uterinas/tratamento farmacológico , Bombas de Infusão Implantáveis , Neoplasias Ovarianas/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateteres de Demora , Esquema de Medicação , Etoposídeo/administração & dosagem , Feminino , Humanos , Infusões Parenterais , Pessoa de Meia-Idade , Indução de Remissão
7.
Biochem Biophys Res Commun ; 184(1): 86-92, 1992 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1567460

RESUMO

Inhibitors of phenoloxidase were identified in pupae of the housefly, Musca domestica L. The phenoloxidase inhibitors were purified from final instar pupae of the housefly by a combination of ammonium sulfate fractionation, ion-exchange chromatography, gel filtration and reverse-phase high performance liquid chromatography. The potent phenoloxidase inhibitors were heat-stable low molecular weight peptides with an inhibition constant of nM range. To the best of our knowledge, this is the first time that endogenous phenoloxidase inhibitors have been identified among the insects, and probably also among the invertebrates. It is likely that the inhibitors play a central role in regulating the action of active phenoloxidases and will also serve as important tools for understanding the structures and functions of phenoloxidases, as well as their role in insect metamorphosis.


Assuntos
Inibidores Enzimáticos/isolamento & purificação , Moscas Domésticas , Monofenol Mono-Oxigenase/antagonistas & inibidores , Peptídeos/isolamento & purificação , Sequência de Aminoácidos , Animais , Ligação Competitiva , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Inibidores Enzimáticos/farmacologia , Cinética , Larva , Dados de Sequência Molecular , Peso Molecular , Peptídeos/farmacologia , Pupa
8.
Gan To Kagaku Ryoho ; 18(11): 1795-9, 1991 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-1877820

RESUMO

Malignant gynecologic tumors are liable to encourage intraperitoneal dissemination and liver metastasis. Using an implantable reservoir (R), we undertook intraperitoneal (ip) administration of CDDP (P) and etoposide (E). After the ip injection of 150 mg of P, 300 mg of E was diluted with 1,500 ml of saline solution through the R. P and E of the intraperitoneal fluid and blood were measured after the administration, and the therapeutic results were evaluated. The blood concentration of P and E reached peaks at 30-60 minutes and at about 4 hours, respectively, after administration. Detectable levels of both P and E were observed at up to 48 hours after administration. In the first treatment of patients who showed severe peritonitis carcinomatosa and high intraperitoneal levels of proteins, the transfer to blood of P from the peritoneal cavity was slow, but as the treatment progressed (second and third administrations) protein binding P decreased and peritoneal permeability improved. Both maximum blood P concentrations and the concentrations of free P were also increased 48 hours after administrations. The area under the curves (AUC) of the blood free P and E concentrations were 8.0 and 274.0 (microgram/ml x h), respectively, which were higher than those following intravenous administration. The results showed 3 CR and 6 PR. This ip regimen obtained a 64.3% response rate for measurable lesions. A patient in stage IV of ovarian cancer showed marked remission of a liver metastatic focus. Repeated ip administration through R proved to be effective by means of systemic therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bombas de Infusão Implantáveis , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Uterinas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Cisplatino/administração & dosagem , Cisplatino/farmacocinética , Terapia Combinada , Citodiagnóstico , Esquema de Medicação , Etoposídeo/administração & dosagem , Etoposídeo/farmacocinética , Feminino , Humanos , Infusões Parenterais/métodos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Reoperação , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia
9.
Nihon Sanka Fujinka Gakkai Zasshi ; 42(7): 689-96, 1990 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-2212806

RESUMO

The serum concentrations of various hormones which included hPL, progesterone(P), estradiol(E2) and 17 alpha-hydroxyprogesterone (17P) in serum, and hCG in urine were measured simultaneously in patients with threatened abortion to evaluate the prognosis. Ultrasound scanning was also undertaken. One hundred and thirty-six patients at 5 to 8 weeks of gestation were divided into two groups retrospectively. Group A consisted of 99 patients with a good prognosis and group B consisted of 37 patients who aborted spontaneously. The mean concentrations of hormones, and ultrasound findings (GS, CRL and FHM) were not significantly different in both groups at 5 weeks. An attempt was made to apply the data to the computation in multivariate analysis. By discriminant analysis, 100% reliability was achieved in separating the two groups according to hormone levels only at this stage of pregnancy. At 6 weeks, the hCG, P and E2 values were statistically higher in group A than B. Because of the overlapping of the data, principal component analysis was attempted. Two groups were roughly separated. The values for factor loading indicated that GS, CRL and 17P effective in making the separation possible. At 7 and 8 weeks of gestation, the mean concentrations of hCG, hPL, P and E2 were significantly higher in A than B. The factor loading values indicated that ultrasound findings were essential in separating into two groups. These results suggested that hormonal analysis may be useful in assessing the prognosis in threatened abortion in the early stage of gestation (5 and 6 weeks), while ultrasound findings make an accurate prediction for the prognosis possible after 7 weeks of gestation.


Assuntos
Ameaça de Aborto/diagnóstico , Gonadotropina Coriônica/urina , Prolactina/sangue , Ameaça de Aborto/diagnóstico por imagem , Estradiol/sangue , Feminino , Humanos , Análise Multivariada , Gravidez , Progesterona/sangue , Prognóstico , Ultrassonografia
10.
Agric Biol Chem ; 54(4): 921-6, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1368551

RESUMO

An endo-1,3-beta-D-xylanase (1,3-beta-D-xylan xylanohydrolase, EC 3.2.1.32) was purified from the culture fluid of Pseudomonas sp. PT-5 by ammonium sulfate fractionation, DEAE-Sepharose CL-6B, Toyopearl HW-50S, and Butyl-Toyopearl 650 M column chromatography. The purified enzyme gave a single band on polyacrylamide gel disc electrophoresis and its molecular weight was 35,000 by SDS-polyacrylamide gel electrophoresis. The enzyme was stable from pH 5.5 to 8.0 and had its maximum activity at pH 7.5. The enzyme rapidly reduced the viscosity of glycol beta-1,3-xylan solutions and produced xylose and xylooligosaccharides from seaweed beta-1,3-xylan. The enzyme activity was greatly inhibited by Hg2+, SDS, ethylenediamine tetraacetic acid (EDTA), and N-bromosuccinimide (NBS).


Assuntos
Glicosídeo Hidrolases/isolamento & purificação , Pseudomonas/enzimologia , Sequência de Aminoácidos , Aminoácidos/análise , Cromatografia em Papel , Eletroforese em Gel de Poliacrilamida , Focalização Isoelétrica , Dados de Sequência Molecular , Peso Molecular , Especificidade por Substrato , Xilano Endo-1,3-beta-Xilosidase , Xilanos/metabolismo
11.
Nihon Sanka Fujinka Gakkai Zasshi ; 41(7): 867-74, 1989 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-2529331

RESUMO

To study the role of prostaglandin (PG) and steroids on the mechanism of parturition, levels of 13,14-dihydro-15-keto-prostaglandin F2 alpha (dhk.PGF2 alpha) and dehydroepiandrosterone-sulfate (DHA-S) in amniotic fluid and plasma during late pregnancy, labor, and puerperium, were measured by radioimmunoassay and gas chromatography-mass spectrometry. Seven patients at term were selected for this study and labor was induced by amniotomy. Amniotic fluid and maternal peripheral blood were obtained simultaneously from each individual at A) the artificial rupture of the membranes before the onset of labor, B) the onset of labor, C) the second stage of labor, D) the delivery, and E) 2 hours postpartum. No increase in either amniotic fluid or plasma dhk-PGF2 alpha was noticed when compared before and at the onset labor. However, there was a steady increase during labor and the maximum was reached at delivery. The dhk-PGF2 alpha concentration in amniotic fluid correlated well with that in maternal plasma. A similar pattern was observed in the DHA-S levels both in amniotic fluid and plasma. No apparent change was observed before the onset of labor, but there was a tendency to increase during labor. A significant correlation between the levels of dhk.PGF2 alpha and DHA-S in amniotic fluid was noticed. From the results obtained above, it is suggested that PG and DHA-S may be involved not in the initiation of labor but in the promotion of parturition. The biological significance of DHA-S on PG levels remains to be clarified.


Assuntos
Líquido Amniótico/metabolismo , Desidroepiandrosterona/análogos & derivados , Dinoprosta/análogos & derivados , Trabalho de Parto/metabolismo , Gravidez/metabolismo , Desidroepiandrosterona/sangue , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona , Dinoprosta/sangue , Dinoprosta/metabolismo , Feminino , Sangue Fetal/metabolismo , Humanos , Trabalho de Parto/sangue , Gravidez/sangue
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