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1.
J Perinatol ; 28(9): 646-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18756276

RESUMO

A total of 4 of 153 low birth weight infants at our hospital were found to have pseudo-Bartter syndrome in 2005 and 2006. The neonates (two of whom were twins; light for gestational age 2, appropriate for gestational age 1 and small for gestational age 1) showed symptoms of apnea and/or poor feeding or patent ductus arteriosus, which disappeared by day 4. Hypokalemia, hypochloremia and metabolic alkalosis normalized by day 8. The mothers had repeatedly rushed to the restroom after eating while in hospital, and were lighter at delivery than before pregnancy; however, vomiting was not observed. The mothers had several stress factors related to pregnancy, and all recovered from the eating disorder after delivery. Urinary Cl/creatinine (mequiv. mg(-1)) and serum Mg in the infants were <0.1 and 1.6 to 2.3 mg per 100 ml, respectively. Eating disorder during pregnancy may have caused Bartter-like syndrome and weight loss, and led to the same syndrome and intrauterine growth retardation in the offspring. Therefore, a hidden maternal eating disorder may underlie neonatal pseudo-Bartter syndrome.


Assuntos
Síndrome de Bartter/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Complicações na Gravidez , Acidose/sangue , Acidose/etiologia , Cloretos/sangue , Doenças em Gêmeos/etiologia , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Feminino , Seguimentos , Humanos , Hipopotassemia/etiologia , Hiponatremia/sangue , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Estresse Psicológico/complicações
2.
Arch Dis Child Fetal Neonatal Ed ; 91(5): F359-62, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16595591

RESUMO

BACKGROUND: There have been only a few reports on the renin-angiotensin system in low birthweight infants; in particular, plasma angiotensin II concentrations have not been studied. AIM: To investigate plasma angiotensin II concentrations in early neonatal infants including low birthweight infants. METHODS: Forty six patients were studied, of whom 14 weighed not less than 2500 g (normal birth weight), 16 weighed less than 2500 g but not less than 1500 g (moderately low birth weight), and 16 weighed less than 1500 g (very low birth weight). Blood samples were collected twice, on day 0 and day 7. Angiotensin II concentration was assayed using an enzyme immunoassay kit with a microplate. RESULTS: Geometric means of angiotensin II concentrations on day 7 were 19 pg/ml in the normal birthweight group, 28 pg/ml in the moderately low birthweight group, and 76 pg/ml in the very low birthweight group. The concentrations on day 7 in the very low birthweight group were significantly higher than those in the normal birthweight and moderately low birthweight groups (p = 0.005, p = 0.031). There were significant correlations between angiotensin II concentration on day 7 and gestational age (r(s) = -0.4, p = 0.007) and birth weight (r(s) = -0.36, p = 0.016). CONCLUSIONS: Specific physiological conditions associated with a very low birth weight are thought to be responsible for the increased concentration of angiotensin II on day 7. It is necessary to measure angiotensin II concentration for a longer period after birth and study the factors that could influence it.


Assuntos
Angiotensina II/sangue , Recém-Nascido/sangue , Envelhecimento/sangue , Peso ao Nascer , Idade Gestacional , Humanos , Recém-Nascido de Baixo Peso/sangue , Recém-Nascido de muito Baixo Peso/sangue
3.
J AOAC Int ; 84(5): 1475-83, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11601467

RESUMO

A flow-injection system was developed for the determination of ethanol with an immobilized enzyme-reactor column. This system, which consisted of hand-made reactor columns packed with alcohol oxidase and horseradish peroxidase immobilized onto chitosan beads, and a fluorometric detector, was applied to the determination of ethanol in liquor samples. Under the recommended conditions, the ethanol, which was present in the pretreated samples, was converted to hydrogen peroxide when it was passed through the immobilized alcohol oxidase (AOD) column with 0.1 mol/dm3 phosphate buffer (pH 7.0). A sample can be analyzed with this system in <10 min. The calibration curve for ethanol was linear from 2.0 to 0.1 mg/dm3. The determination limit, which was defined by the difference between the sample peak and blank peak, was estimated to be 50 microg/dm3 for ethanol. Interferences from some substances present in actual liquor samples decreased the analytical response and activity of the immobilized AOD-reactor column, but they were removed by dilution and pretreatment with an octyldecylsilane cartridge.


Assuntos
Oxirredutases do Álcool/química , Bebidas Alcoólicas/análise , Etanol/análise , Peroxidase/química , Quitina/análogos & derivados , Quitosana , Enzimas Imobilizadas , Análise de Injeção de Fluxo , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
4.
J Chromatogr Sci ; 39(10): 405-10, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11669364

RESUMO

Gold and copper ions react with syn-phenyl-2-pyridylketoxime (PPKO) at 40 degrees C to form neutral chelates. Metal-PPKO chelates subsequently become preconcentrated on a minicolumn packed with a divinylbenzene-methacrylate copolymer. By switching the valve, these chelates are separated on the silica-based phenyl column and detected with a photometric detector. These processes occur automatically except for chelation. The results of the chelation, preconcentration, and separation conditions studies are presented. Calibration curves for Au and Cu ions are linear from nanograms per milliliter (parts per billion) to micrograms per milliliter (parts per million) in the original solution. The precision for 0.5-ppm standards of Au and Cu is 2.1 and 0.9 relative standard deviation (%), respectively. The accuracy of the present method is verified for Au and Cu based on the analysis of a standard alloy of the National Institute of Standards and Technology (NIST). The limits of detection for Au and Cu are 16.7 and 0.6 ppb, respectively. The effects of foreign ions on the determination of Au and Cu are discussed.

5.
Oncol Rep ; 8(6): 1281-3, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11605049

RESUMO

Anomalous junction of the pancreaticobiliary duct (AJPBD) is a congenital anomaly associated with gallbladder carcinoma. Especially patients with noncystic dilatation and without dilatation of the biliary tract are at risk of gallbladder carcinoma. A 56-year-old woman with advanced gallbladder cancer associated with AJPBD but without dilatation of the biliary tract was treated at our hospital. Although histologically cancer cells remained in the layer of the proprial mucosa, extensive metastases to lymph nodes including the paraaorta and peripancreas were detected. According to the TNM classification this case was of Stage IVB. The cancer consisted of medullary round cells, and was diagnosed as undifferentiated carcinoma. After surgery poor prognosis was expected, but three years have elapsed with no recurrence. The case is of interest because of two points of discrepancy: the primary cancer did not show deep invasion but demonstrated extensive lymph node metastases; the cancer was histologically malignant but prognosis was relatively good.


Assuntos
Ductos Biliares/anormalidades , Carcinoma/diagnóstico , Neoplasias da Vesícula Biliar/diagnóstico , Ductos Biliares/cirurgia , Carcinoma/patologia , Carcinoma/cirurgia , Feminino , Neoplasias da Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Ductos Pancreáticos/anormalidades
6.
Gan To Kagaku Ryoho ; 28(3): 407-10, 2001 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-11265415

RESUMO

AML with trilineage myelodysplasia (AML/TMDS) is recognized as having of poor prognosis due to its resistance to chemotherapy in comparison with de novo AML. An AML/TMDS patient who failed to respond to ordinary induction therapy achieved complete remission with combination therapy consisting of all-trans retinoic acid (ATRA) and low-dose Ara-C. No serious toxicity was observed. ATRA combined with low-dose Ara-C could be an alternative treatment for this kind of patient.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Defeitos do Tubo Neural/tratamento farmacológico , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Citarabina/administração & dosagem , Feminino , Humanos , Pessoa de Meia-Idade , Defeitos do Tubo Neural/complicações , Tretinoína/administração & dosagem
7.
Talanta ; 53(6): 1117-26, 2001 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-18968203

RESUMO

Antimony(III) was preconcentrated on activated carbon (AC) as the antimony(III)-pyrogallol complex. Prior to the preconcentration, antimony(V) was reduced to antimony(III) with potassium iodide and ascorbic acid. The antimony adsorbed on the AC was determined by graphite furnace atomic absorption spectrometry as an AC suspension. The method was applied to differential determination of trace amounts of antimony in natural water.

8.
J Vet Med Sci ; 62(8): 881-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10993186

RESUMO

The regional variation in the intraepithelial lymphocytes (IELs) in the small intestine was examined in BALB/c male and female mice and C3H/He and C57BL/6 male mice. The small intestines were taken from 11 to 12-week-old mice and divided equally into 3 parts (the proximal, middle and distal parts). IELs were isolated from each part of the intestine and analyzed with flow cytometer. The number of IELs was highest in the proximal part and lowest in the distal part. The distribution of IEL subsets was markedly different between the proximal and the distal parts, and that in the middle part showed the intermediate pattern. The percentage of alphabeta T cells were higher in the distal part. In alphabeta T cell subset, the percentage of CD8alphaalpha T cells was higher in the proximal part, whereas those of CD4 and CD4CD8alphaalpha double positive T cells were higher in the distal part. In gammadelta T cell subset, no regional variations were found. The regional variations in the number and subsets of IELs showed almost the same patterns between male and female BALB/c mice and similar patterns among three strains of mice. This strongly suggests that the regional variations in the small intestinal IELs are common to mouse species.


Assuntos
Intestino Delgado/citologia , Linfócitos/citologia , Camundongos Endogâmicos/anatomia & histologia , Animais , Técnicas de Cultura , Feminino , Mucosa Intestinal/citologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C/anatomia & histologia , Camundongos Endogâmicos C3H/anatomia & histologia , Camundongos Endogâmicos C57BL/anatomia & histologia , Especificidade da Espécie
9.
Comp Med ; 50(1): 39-42, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10987666

RESUMO

BACKGROUND AND PURPOSE: Regional variations in the intraepithelial lymphocytes (IELs) in the mouse small intestine were examined. METHODS: The small intestine was taken from six 12-week-old BALB/c mice and divided equally into three parts (proximal, middle, and distal). The IELs were isolated from each part of the intestine and analyzed by use of flow cytometry. RESULTS: The number of IELs in the distal part of the small intestine was significantly lower than that in the proximal and middle parts (P < 0.01). The distribution of IEL subsets was markedly different between the proximal and the distal parts, and that in the middle part had an intermediate pattern. The percentage of alphabetaT cells and expression of Thy-1.2 on the alphabetaT and gammadeltaT cells were higher in the distal part (P < 0.01). The percentage of CD8alphaalpha and of double-negative T cells were higher in the proximal part, whereas that of CD4CD8alphaalpha double-positive T cells was higher in the distal part (P < 0.01). Regional variations were found mainly in the extrathymically developed T cell subsets. CONCLUSION: Local development of IELs may differ between regions of the small intestine.


Assuntos
Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Subpopulações de Linfócitos/imunologia , Camundongos Endogâmicos BALB C/imunologia , Animais , Anticorpos Monoclonais , Centrifugação com Gradiente de Concentração/veterinária , Citometria de Fluxo/veterinária , Mucosa Intestinal/química , Intestino Delgado/química , Subpopulações de Linfócitos/química , Masculino , Camundongos , Organismos Livres de Patógenos Específicos
10.
Intern Med ; 39(5): 416-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10830186

RESUMO

A 61-year-old woman, who was diagnosed in 1982 as having polycythemia vera, was admitted to our hospital in July 1998 because of a splenic tumor in an enlarged spleen due to myelofibrosis. As it was difficult to identify the etiology of the splenic tumor, partial splenectomy was carried out. The resected tumor proved to be an extremely proliferative lesion as the result of extramedullary hematopoiesis. Since it is difficult to diagnose the etiology of splenic tumor, the collection and analysis of reports of relevant cases may well facilitate diagnosis.


Assuntos
Hematopoese , Mielofibrose Primária/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Policitemia Vera/complicações , Mielofibrose Primária/etiologia , Mielofibrose Primária/patologia , Baço/patologia , Neoplasias Esplênicas/diagnóstico , Tomografia Computadorizada por Raios X
11.
J Chromatogr A ; 844(1-2): 403-8, 1999 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-10399334

RESUMO

This study describes the utilization of carbonyl- 2,4-dinitrophenylhydrazine (DNPH) derivatives for the determination of a micro amount of carbonyl compounds in air by liquid chromatography-mass spectrometry (LC-MS). After the carbonyl compounds are collected using a Waters Sep-Pak C18 cartridge column with-impregnated DNPH on octadecylsilica, they are eluted by acetonitrile as carbonyl-DNPH derivatives. A 20-mm3 aliquot of eluent is injected into the LC-MS system. The four derivatives (formaldehyde-, acetaldehyde-, acrolein- and acetone-DNPH) were eluted within 7 min with acetonitrile-water (60:40, v/v) as the mobile phase. The proposed method offers sub-ppb sensitivity and good reproducibility and was applied to the determination of these carbonyl compounds in actual air samples from store rooms, laboratories and offices. The relative standard deviations for these samples (n = 6) were 1 to 3%.


Assuntos
Poluentes Atmosféricos/análise , Ar/análise , Aldeídos/análise , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Fenil-Hidrazinas/química , Acetaldeído/análise , Acetona/análise , Acroleína/análise , Formaldeído/análise , Microquímica , Controle de Qualidade
12.
Exp Anim ; 48(2): 115-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10374073

RESUMO

Diurnal changes in small intestinal intraepithelial lymphocytes (IELs) were examined in 8- to 10-week-old BALB/cA male mice. The ratio of T cell subsets expressing CD8 alpha alpha homodimer/CD8 alpha beta heterodimer was found to be higher in the dark period than that in the light period. Increased expression of Thy-1.2 on gamma delta T cells was also observed in the light period. No significant changes were found in other subsets. This is the first report to document diurnal changes in the small intestinal IELs in mice.


Assuntos
Ritmo Circadiano , Células Epiteliais/imunologia , Intestinos/imunologia , Linfócitos T/imunologia , Animais , Intestinos/citologia , Subpopulações de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos BALB C
13.
Talanta ; 46(6): 1311-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18967259

RESUMO

A sample solution containing less than 0.5 mug of As was adjusted to pH 2. As in the solution was collected on activated carbon (AC) as molybdoarsenate. The AC was directly introduced as an AC suspension into a graphite furnace atomizer, and the concentration of As was determined by atomic absorption spectrometry (AAS). This method is relatively free from interference caused by coexisting ions. The calibration curve was linear up to 0.1 mg l(-1), and limit of detection of As was 0.004 mg l(-1). When 1000 ml of sample solution is preconcentrated to 5 ml (enrichment factor is 200-fold) 0.02 mug l(-1) of As could be determined, and relative standard deviation was below 4.0% (by the deuterium background correction system). The method was applied to sea water and well water, and the sum of As(III) and As(V) was determined with satisfactory results.

14.
J Gastroenterol ; 31(2): 254-9, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8680547

RESUMO

We investigated the effect of tryptophan (Trp) on exocrine secretory function, using isolated rat pancreatic acini. Trp inhibited cholecystokinin-octapeptide (CCK-8)-stimulated amylase secretion, causing a downward shift in the dose-response curve. The inhibitory effect of Trp was dose-dependent and was observed only on the sustained secretion, there being no effect on the initial phase of amylase secretion. Trp (10mM) also inhibited amylase secretion in response to carbachol and bombesin, as well as fluoride, a potent activator of guanine-nucleotide binding proteins. Since Ca2+ influx is necessary for sustained secretion, we examined the effect of Trp on Ca2+ influx and efflux. Trp increased the CCK-8-stimulated Ca2+ influx rate without affecting Ca2+ efflux, suggesting that Trp elevates intracellular Ca2+ levels. Increasing intracellular Ca2+ levels with A23187 resulted in the inhibition of CCK-8-stimulated amylase secretion. These results indicate that Trp inhibits CCK-stimulated sustained amylase secretion, in part by increasing Ca2+ influx into acinar cells.


Assuntos
Amilases/metabolismo , Pâncreas/efeitos dos fármacos , Sincalida/farmacologia , Triptofano/farmacologia , Amilases/antagonistas & inibidores , Animais , Cálcio/metabolismo , Carbacol/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Técnicas In Vitro , Masculino , Pâncreas/metabolismo , Parassimpatomiméticos/farmacologia , Ratos , Ratos Wistar , Sincalida/antagonistas & inibidores , Triptofano/administração & dosagem
15.
Talanta ; 42(7): 949-55, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18966316

RESUMO

A trace level of Se was collected on activated carbon (AC) as the Se(IV)-3-phenyl-5-mercapto-1,3,4-thiadiazole-2(3H)-thione (Bismuthiol II) complex. The AC was directly introduced as an AC-suspension into the graphite tube atomizer and the Se concentration was determined by atomic absorption spectroscopy (T. Okutani, T. Kubota, N. Sugiyama and Y. Turuta, Nippon Kagaku Kaishi, (1991) 375). The amount of Se in heavily contaminated samples including sediment, lake water and seawater was determined using this method. The sediments were digested with HNO(3)HClO(4)HF and the interference from AlF(3) was removed using H(3)BO(3)HClO(4). Lake water and seawater were acidified with H(2)SO(4) and digested with KMnO(4). The Se concentrations of these samples were determined by this method with satisfactory results. The above method is simple, rapid and applicable to heavily contaminated samples.

16.
Biochem Biophys Res Commun ; 209(1): 131-8, 1995 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-7726827

RESUMO

We investigated epidermal growth factor (EGF)-induced activation of 85-kDa/110-kDa phosphatidylinositol (PI)-3-kinase and 70-kDa S6 kinase in Chinese hamster ovary cells expressing the human EGF receptor. EGF-induced activation of p70 S6 kinase was comparable to that induced by insulin, whereas that of PI-3-kinase in anti-phosphotyrosine immunoprecipitates was very small compared with insulin. Wortmannin, a p85/p110 PI-3-kinase inhibitor, inhibited EGF-induced activation of p70 S6 kinase in a dose-dependent manner. Given that several proteins homologous to catalytic subunit of p85/p110 PI-3-kinase have been identified and that wortmannin inhibits distinct form of PI-3-kinase, the present results suggest that wortmannin-sensitive kinases that resemble catalytic subunit of p85/p110 PI-3-kinase may participate in the signaling pathway from EGF receptors to p70 S6 kinase.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/genética , Proteínas Serina-Treonina Quinases/metabolismo , Androstadienos/farmacologia , Animais , Células CHO , Clonagem Molecular , Cricetinae , Cricetulus , Ativação Enzimática , Receptores ErbB/metabolismo , Humanos , Insulina/farmacologia , Cinética , Camundongos , Fosfatidilinositol 3-Quinases , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas Quinases S6 Ribossômicas , Wortmanina
17.
J Biol Chem ; 269(49): 31310-4, 1994 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-7527043

RESUMO

The activation of receptor tyrosine kinases generates tyrosine-phosphorylated recognition motifs for the binding of signaling proteins containing Src homology 2 domains. We determined the binding sites of Grb2/Ash, an Src homology 2 domain-containing adaptor protein, within epidermal growth factor (EGF) receptors, using Chinese hamster ovary cells overexpressing human EGF receptor mutants in which one of the autophosphorylation sites was retained. In intact cells, the amount of Grb2/Ash coimmunoprecipitated with mutant receptors retaining tyrosines 992, 1068, 1086, 1148, or 1173 was approximately 10, 85, 55, 50, or 20% of wild-type levels, respectively. The association of Grb2/Ash with in vitro autophosphorylated EGF receptor mutants was detectable in those retaining either tyrosines 1068 or 1086 but not in other mutants including those retaining tyrosine 1148. In peptide inhibition assay, phosphorylated peptides representing tyrosines 1068 and 1086 inhibited the binding of Grb2/Ash to in vitro autophosphorylated wild-type EGF receptors, whereas the other peptides representing tyrosines 992, 1148, and 1173 failed to inhibit the binding. Given that tyrosine 1148 of the activated EGF receptor is a major binding site of Shc (Okabayashi, Y., Kido, Y., Okutani, T., Sugimoto, Y., Sakaguchi, K., and Kasuga, M. (1994) J. Biol. Chem. 269, 18674-18678), these results indicate that tyrosines 1068 and 1086 of activated human EGF receptors are direct high affinity binding sites of Grb2/Ash and that tyrosine 1148 is an indirect binding site through Shc in intact cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Receptores ErbB/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Tirosina/metabolismo , Animais , Células CHO , Células Cultivadas , Cricetinae , Proteína Adaptadora GRB2 , Humanos , Camundongos , Ligação Proteica
18.
J Biol Chem ; 269(28): 18674-8, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-8034616

RESUMO

Autophosphorylation of receptor tyrosine kinases provides binding sites for signaling proteins containing Src homology 2 (SH2) domains. We determined the binding sites of Shc, SH2-containing adaptor protein, within epidermal growth factor (EGF) receptors, using Chinese hamster ovary cells overexpressing EGF receptor mutants in which autophosphorylation sites, either alone or in combination, were replaced by phenylalanine. Binding of Shc to EGF receptor mutants lacking single tyrosine residues at 1148 or 1173 decreased by approximately 60 or approximately 15%, respectively, whereas other single point mutants bound the wild-type level of Shc. Binding of Shc markedly decreased in mutants lacking both tyrosine residues at 1148 and 1173. In peptide inhibition assay, phosphorylated nonameric peptide representing tyrosine 1148, DNPDpYQQDF, but not pentameric peptide, pYQQDF, inhibited the binding of glutathione S-transferase-Shc SH2 domain fusion protein to in vitro autophosphorylated EGF receptors, suggesting that N-terminal sequences adjacent to phosphotyrosine are necessary for the association of Shc. Based on results of peptide inhibition assays in which phosphorylated peptides representing tyrosines 992, 1148, and 1173 inhibited Shc binding to the receptor, we constructed another EGF receptor mutant in which one of these tyrosine residues was retained. The amount of Shc bound to mutant receptors retaining tyrosines 1148, 1173, or 992 was approximately 80, approximately 40, or approximately 10% of wild-type level, respectively. These results indicate that tyrosine 1148 of activated human EGF receptors is a major binding site of Shc and tyrosine 1173 is a secondary binding site in intact cells.


Assuntos
Receptores ErbB/metabolismo , Oligopeptídeos/metabolismo , Tirosina , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , Células CHO , Cricetinae , Receptores ErbB/biossíntese , Glutationa Transferase/biossíntese , Glutationa Transferase/metabolismo , Humanos , Cinética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligodesoxirribonucleotídeos , Oligopeptídeos/química , Fenilalanina , Fosforilação , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , Transfecção
19.
Dig Dis Sci ; 38(7): 1278-83, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8325188

RESUMO

To clarify the effect of islet hormones on pancreatic ductular cell function, we measured the exocrine secretion elicited by 10 pM secretin in the presence or absence of islet hormones using an isolated perfused rat pancreas model. Insulin significantly increased secretin-stimulated pancreatic juice secretion, but not protein secretion. The potentiating effect of insulin on pancreatic juice secretion was concentration-dependent, and the maximal effect was observed with 1 microM insulin. Ouabain, a specific Na+,K(+)-ATPase inhibitor, caused concentration-dependent inhibition of the potentiating effect of insulin without affecting secretin action. Glucagon (100 nM) significantly inhibited secretin-stimulated pancreatic juice secretion and also tended to inhibit protein secretion. A somatostatin analog, SMS 201-995 (10 nM) significantly inhibited both the pancreatic juice and protein secretion stimulated by secretin. The inhibitory effect of SMS 201-995 was concentration-dependent and was maximal at 1-10 nM. These results demonstrate that insulin potentiates the secretory response to secretin, at least partly by increasing Na+,K(+)-ATPase activity, whereas glucagon and somatostatin inhibit this response. Thus, pancreatic islet hormones regulate the secretory function of pancreatic ductular and centroacinar cells.


Assuntos
Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Hormônios Pancreáticos/farmacologia , Secretina/farmacologia , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Técnicas In Vitro , Masculino , Octreotida/farmacologia , Ouabaína/farmacologia , Ductos Pancreáticos/efeitos dos fármacos , Ductos Pancreáticos/metabolismo , Suco Pancreático/efeitos dos fármacos , Suco Pancreático/metabolismo , Ratos , Ratos Wistar , Estimulação Química
20.
Nihon Shokakibyo Gakkai Zasshi ; 90(5): 1425-31, 1993 May.
Artigo em Japonês | MEDLINE | ID: mdl-8320851

RESUMO

In order to clarify the effect of somatostatin of the ductal secretion of the exocrine pancreas, we measured pancreatic juice and protein secretion stimulated with 10 pM secretin and/or 10 pM cholecystokinin (CCK) in the presence or absence of somatostatin analogue, SMS 201-995 (SMS) utilizing the isolated perfused pancreas of rats. SMS significantly inhibited both pancreatic juice flow and protein output elicited by 10 pM secretin without affecting basal secretion. The inhibitory effect of SMS was dose-dependent and maximal inhibition was observed with 1-10 nM. Half-inhibitory dose of SMS for juice secretion was 140 pM. Because CCK is thought to potentiate secretin action on the ductal system, we examined the effect of SMS on pancreatic secretory response to 10 pM secretin in combination with 10 pM CCK. In the experimental system we used, the amounts of pancreatic juice and protein secreted during a 30-min stimulation with secretin and CCK were additive. SMS inhibited both pancreatic juice and protein secretion to the level comparable with that obtained with either stimulus and SMS. SMS had no effect on CCK-stimulated pancreatic juice secretion but significantly inhibited protein output. The present study demonstrated, therefore, that SMS inhibits ductal secretion in response to physiological concentration of secretin.


Assuntos
Octreotida/farmacologia , Pâncreas/metabolismo , Suco Pancreático/metabolismo , Animais , Colecistocinina/antagonistas & inibidores , Colecistocinina/fisiologia , Técnicas In Vitro , Masculino , Proteínas/metabolismo , Ratos , Ratos Wistar , Secretina/antagonistas & inibidores , Secretina/fisiologia
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