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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7535-7538, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892835

RESUMO

The long-term goal of this study is a training system that can simulate medical cases and advise physicians based on quantitative evaluation of neonatal resuscitation. In this paper, we designed and manufactured a neonatal airway management simulator for quantitative evaluation of tracheal intubation. This robotic simulator is equipped with 25 sensors of 6 types, which detect motions that lead to complications, inside the manikin replicated a neonate. A performance experiment of the developed sensor and an evaluation experiment with physicians were conducted. We observed that an erroneous operation in the laryngoscopy can be detected by the sensors in our simulator.


Assuntos
Intubação Intratraqueal , Ressuscitação , Manuseio das Vias Aéreas , Humanos , Recém-Nascido , Laringoscopia , Manequins
2.
J Histochem Cytochem ; 31(7): 967-70, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6854009

RESUMO

Sulfenylation with 2-nitrophenylsulfenyl chloride (NPS-Cl), which is specific for tryptophyl and cysteinyl residues in protein, was applied to quantitative histochemistry. By measurement of the absorbance values at 370 nm of sections stained with NPS-Cl, Beer-Lambert's law was found to hold for NPS staining. Treatment of NPS-stained sections with 2-mercaptoethanol (ME) (NPS-ME staining) resulted in sulfenylation of tryptophyl residues only. For determination of the amounts of tryptophyl and cysteinyl residues per unit of protein, protein staining with Coomassie Brilliant Blue (CB) was combined with NPS and NPS-ME staining. CB and NPS-CBB staining also followed Beer-Lambert's law. By measuring the absorbance values at 370 and 650 nm of doubly stained sections, the relative contents of tryptophyl and cysteinyl residues in various tissue proteins were calculated. This method will be useful for the investigation of changes in both protein amount and composition.


Assuntos
Citometria de Fluxo/métodos , Proteínas/análise , Compostos de Sulfidrila/análise , Triptaminas/análise , Animais , Cisteína/análise , Histocitoquímica , Fígado/análise , Masculino , Músculos/análise , Nitrobenzenos/farmacologia , Ratos , Ratos Endogâmicos , Corantes de Rosanilina/farmacologia
3.
J Histochem Cytochem ; 45(10): 1417-25, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9313803

RESUMO

We studied the effects of two tissue protectants, polyvinyl alcohol (PVA) and agarose gel, on a kinetic parameter of lactate dehydrogenase LDH that is assumed to be related to the extent of diffusion of the enzyme out of tissue sections during its histochemical assay. the kinetics of the enzyme in mouse gastrocnemius (skeletal) muscle fibers and periportal hepatocytes were determined in unfixed sections incubated either on substrate (L-lactate)-containing agarose gel films or in aqueous assay media in the presence or absence of 18% PVA. The absorbances of the formazan final reaction products at their isobestic point were measured continuously in the cytoplasm of individual cells as a function of incubation time, using a real-time image analysis system. Whichever incubation medium was used, the absorbances in the two cell types increased nonlinearly during the first minute of incubation but linearly for incubation times between 1 and 3 min. The nonlinearity of the LDH reaction was analyzed using the equation vi-v = a0A, where vi is the observed initial velocity determined from the absorbance changes during the first 10 sec of incubation and v and 0 A are respectively the gradient and intercept on the absorbance axis of the linear regression line of the absorbance on incubation times between 1 and 3 min. The plots of the observed (vi-v) against 0 A were linear. Their gradients a were characteristic for each cell type and tissue protectant. The a values for skeletal muscle fibers were 12-43% lower than those for hepatocytes. The a value for hepatocytes obtained with the PVA method was 32% lower than that determined with the gel film method. For skeletal muscle fibers, the a values determined by the two methods were almost the same. Addition of excess pyruvate to the aqueous assay medium had no effects on a for either muscle fibers or hepatocytes. In contrast, a was zero for sections of polyacrylamide gels containing purified enzyme, whether incubated on agarose films or in PVA media. These data confirmed that the constant a is related to the extent to which the enzyme diffuses out of sections during incubation but not to product inhibition of LDH by pyruvate. PVA was more effective for protecting diffusion of LDH from hepatocytes than from skeletal muscle fibers, possibly because hepatocytes contain a greater proportion of diffusable (unbound) LDH than skeletal muscle fibers.


Assuntos
L-Lactato Desidrogenase/metabolismo , Fígado/enzimologia , Músculo Esquelético/enzimologia , Animais , Processamento de Imagem Assistida por Computador , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Músculo Esquelético/efeitos dos fármacos , Álcool de Polivinil/farmacologia , Coelhos , Sefarose/farmacologia , Fatores de Tempo , Preservação de Tecido
4.
J Histochem Cytochem ; 45(10): 1427-31, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9313804

RESUMO

We determined the Michaelis constant (K(m)) and maximal velocity (Vmax) of lactate dehydrogenase (LDH) in periportal hepatocytes and skeletal muscle fibers by three different histochemical assay methods. Unfixed sections of mouse liver and gastrocnemius were incubated at 37C either on substrate (L-lactate)-containing agarose gel films or in aqueous assay media with and without 18% polyvinyl alcohol (PVA) as a tissue protectant. The absorbances of the formazan final reaction products were continuously measured at 584 nm in the cytoplasm of individual cells as a function of incubation time, using an image analysis system. The kinetic parameters of purified rabbit skeletal muscle LDH incorporated into polyacrylamide gel sections were similarly determined. The intrinsic initial velocities (vi) of LDH, corrected for "nothing dehydrogenase," were determined as described in the previous article. The Km and Vmax were calculated from Hanes plots of s/vi on L-lactate concentration (s). The Km values obtained with three assay methods were similar and in the range of 21.1-21.9 mM for pure LDH, 8.62-13.5 mM for LDH in mouse periportal hepatocytes, and 13.3-17.9 mM for LDH in mouse skeletal muscle fibers. The Vmax values determined on agarose gel substrate films and in aqueous assay media without PVA were in good agreement but were 53-65% lower when 18% PVA was included in the medium. These results indicate that catalytic center activity kcat of LDH is retarded by the high viscosity of PVA media because PVA hardly inhibited the enzyme. The K(m) values of LDH determined histochemically in skeletal muscle fibers and periportal hepatocytes were respectively three to five times and two to three times higher than those determined biochemically. These differences may be due to interactions of LDH with intracellular components.


Assuntos
L-Lactato Desidrogenase/metabolismo , Fígado/enzimologia , Músculo Esquelético/enzimologia , Animais , Processamento de Imagem Assistida por Computador , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Músculo Esquelético/efeitos dos fármacos , Álcool de Polivinil/farmacologia , Coelhos , Sefarose/farmacologia , Fatores de Tempo , Preservação de Tecido
5.
Cancer Lett ; 149(1-2): 221-6, 2000 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-10737728

RESUMO

During size exclusion HPLC, ATN-2 binding protein separated from human and mouse sera, SCCVII and colon 26 tumor tissues were found in fraction 13 (A: estimated molecular weight 70,000). Fraction 13(A) of human sera was exclusively reactive to the human hemopexin antibody. During two-dimensional electrophoresis and amino acid sequence analysis, Fraction 13(A) of C3H/He mouse sera was found to have partial homology with the mouse hemopexin precursor. Glycoprotein with the same domain structure of hemopexin has been proposed to be an important carrier protein that forms the tumor-localizing activity of water-soluble porphyrin.


Assuntos
Neoplasias do Colo/metabolismo , Hemopexina/metabolismo , Porfirinas/metabolismo , Animais , Proteínas de Transporte/metabolismo , Eletroforese em Gel Bidimensional , Hemopexina/análise , Humanos , Camundongos , Porfirinas/análise
6.
Aliment Pharmacol Ther ; 20 Suppl 1: 48-53, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15298605

RESUMO

BACKGROUND: In patients with Helicobacter pylori infection, the concentration of nitrite in gastric juice is elevated. The degree of elevation correlates with that of inflammation and H. pylori density. AIM: The aim of this study was to examine hypoacidity and high nitrite levels related to H. pylori infection in patients with gastric cancer. METHODS: We studied 88 patients with more than one history of endoscopic mucosal resection (EMR) for early gastric cancer and 88 age-matched controls. Concentration of nitrite in gastric juice was measured by Griess reaction, and serum pepsinogen levels were measured by RIA. RESULTS: Multiple malignant lesions were found in 20 of the 88 patients. Serum gastrin, gastric juice pH and nitrite levels in patients with gastric cancer were significantly higher and pepsinogen I and pepsinogen I/II significantly lower than in control subjects. Pepsinogen I level and I/II ratio were lower and gastric juice pH was higher in the protruded-type group than in the depressed-type group. Pepsinogen I and pepsinogen I/II were lower and gastric juice pH was higher in multiple than in single cases. CONCLUSIONS: Hypoacidity combined with high gastric juice nitrite induced by H. pylori infection is associated with the intestinal type of gastric cancer, especially protruded lesions.


Assuntos
Suco Gástrico/química , Infecções por Helicobacter/complicações , Helicobacter pylori , Nitritos/metabolismo , Neoplasias Gástricas/etiologia , Idoso , Estudos de Casos e Controles , Feminino , Ácido Gástrico , Determinação da Acidez Gástrica , Gastrinas/sangue , Infecções por Helicobacter/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pepsinogênios/sangue , Estudos Prospectivos , Neoplasias Gástricas/sangue
7.
J Biochem ; 80(3): 435-47, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10284

RESUMO

The interactions of the substrate analogs beta-methyl-GlcNAc, (GlcNAc)2, and (GlcNAc)3 with hen egg-white lysozyme [EC 3.2.1.17] in which an ester linkage had been formed between Glu 35 and Trp 108 (108 ester lysozyme), were studied by the circular dichroic and fluorescence techniques, and were compared with those for intact lysozyme. The binding constants of beta-methyl-GlcNAc and (GlcNAc)2 to 108 ester lysozyme were essentially the same as those for intact lysozyme in the pH range of 1 to 5. Above pH 5, the binding constants of these saccharides to 108 ester lysozyme did not change with pH, while the binding constants to intact lysozyme decreased. This indicates that Glu 35 (pK 6.0 in intact lysozyme) participates in the binding of these saccharides. The extent and direction of the pK shifts of Asp 52 (pK 3.5), Asp 48 (pK 4.4), and Asp 66 (pK 1.3) observed when beta-methyl-GlcNAc is bound to 108 ester lysozyme were the same as those for intact lysozyme. The participation of Asp 101 and Asp 66 in the binding of (GlcNAc)2 to 108 ester lysozyme was also the same as that for intact lysozyme. These findings indicate that the conformations of subsites B and C are not changed by the formation of the ester linkage. On the other hand, the binding constants of (GlcNAc)3 to 108 ester lysozyme were higher than those for intact lysozyme at all pH values studied. This result is interpreted in terms of an increase in the affinity for a GlcNAc residue of subsite D, which is situated near the esterified Glu 35.


Assuntos
Acetilglucosamina/análogos & derivados , Glucosamina/análogos & derivados , Glutamatos , Muramidase/metabolismo , Triptofano , Dicroísmo Circular , Ésteres , Concentração de Íons de Hidrogênio , Oligossacarídeos/metabolismo , Ligação Proteica , Temperatura , Termodinâmica
8.
J Biochem ; 77(5): 993-1006, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-239938

RESUMO

The pH dependence of the extrinsic circular dichroic (CD) band at 375 nm of hen egg-white lysozyme [EC 3.2.1.17] in which Trp 62 had selectively 2-nitrophenylsulfenylated (NPS-lysozyme) was studied. This pH dependence was interpreted in terms of the participation of Glu 35 (pK 6.2), Asp 101 (pK 4.6), and Asp 66 (pK1.5). The fact that the ionization of Glu 35 affects the extrinsic CD band of the NPS chromophore attached to Trp 62 confirms the presence of a relation between the state of Trp 62 and the ionization state of one of the catalytic groups, Glu 35, in hen lysozyme, as proposed by Ikeda and Hamaguchi (J. Biochem., 74, 221-230 (1973)). The pH dependence of the binding constants of the dimer and trimer of N-acetylglucosamine (GlcNAc) and the beta-methyl glycoside of GlcNAc (beta-methyl-GlcNAc) to NPS-lysozyme were studied by measuring the changes in the extrinsic CD band. The changes in the CD spectrum on the binding of (GlcNAc)3 and (GlcNAc)2 were very similar to each other but were different from that on the binding of beta-methyl-GlcNAc. However, beta-methyl-GlcNAc competitively inhibited the binding of (GlcNAc)2 to NPS-lysozyme. The binding constants of the three saccharides to NPS-lysozyme were much smaller than those for intact lysozyme. The pH dependence of the binding constants of (GlcNAc)2 and (GlcNAc)3 were interpreted in terms of the participation of Glu 35 (pK 6.2), Asp 52 (pK 3.3), Asp 101 (pK 4.6), and Asp 66 (pK 1.5). These pK values are very similar to those for intact lysozyme, as determined by Kuramitsu et al. (J. Biochem., 76, 671-683 (1974); 77, 291-301 (1975). Comparison of the binding constants of Mn2qnd Co2'ons to the catalytic carboxyls of NPS-lysozyme with those to intact lysozyme also indicated that the catalytic site of NPS-lysozyme is scarcely affected by this modification. When (GlcNAc)2 or (GlcNAc)3 is bound to NPS-lysozyme, pK shifts of Glu 35, Asp 101, and Asp 66 occurred in the same directions as for intact lysozyme. In addition, a pK shift of Asp 52, which has not been observed for intact lysozyme, occurred. The participation of Asp 52 was also observed in the binding of beta-methyl-GlcNAc. However, the binding of the monomer to NPS-lysozyme produced no significant pK shifts of Glu 35 and Asp 101, in contrast to the situation for intact lysozyme. These facts indicate a small difference in the binding orientation of the saccharides between the modified and intact lysozymes.


Assuntos
Acetilglucosamina , Glucosamina/análogos & derivados , Muramidase/metabolismo , Triptofano/análogos & derivados , Acetilglucosamina/análogos & derivados , Acetilglucosamina/metabolismo , Animais , Ácido Aspártico , Sítios de Ligação , Galinhas , Dicroísmo Circular , Cobalto/farmacologia , Clara de Ovo , Glutamatos , Concentração de Íons de Hidrogênio , Manganês/farmacologia , Nitrobenzenos , Concentração Osmolar , Ligação Proteica , Conformação Proteica , Ácidos Sulfênicos
9.
J Biochem ; 80(3): 425-34, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10283

RESUMO

The binding constants of alpha- and beta-GlcNAc to hen and turkey lysozymes [EC 3.2.1.17] were determined at various pH's using the method proposed by Ikeda and Hamaguchi (1975) J. Biochem. 77, 1-16). The pH dependence of the binding of beta-GlcNAc to hen lysozyme was essentially the same as that for turkey lysozyme. The pH dependence curves of the binding constants of beta-GlcNAc to hen and turkey lysozymes were interpreted in terms of the participation of Glu 35 (pK 6.0), Asp 52 (pK 3.5), Asp 48 (pK 4.5), and Asp 66 (pK 1.5). The binding constants of alpha-GlcNAc to hen and turkey lysozymes were the same below pH 3.5 but were different above this pH. The main participant residues in the binding of alpha-GlcNAc were Glu 35, Asp 48, and Asp 66 for hen lysozyme and Glu 35 and Asp 66 for turkey lysozyme. The results obtained here were well explained by the following assumptions: (1) above about pH 4, alpha-GlcNAc binds to hen lysozyme in both alpha- and beta-modes, which correspond to the binding orientation of alpha-GlcNAc and that of beta-GlcNAc, respectively, as determined by X-ray crystallographic studies, but it binds predominantly in the beta-mode below about pH 4, (2) beta-GlcNAc binds to hen and turkey lysozymes predominantly in the beta-mode above about pH 4 and in both alpha- and beta-modes below pH 4, and (3) alpha-GlcNAc binds to turkey lysozyme predominantly in the beta-mode over the whole pH range studied.


Assuntos
Acetilglucosamina/metabolismo , Glucosamina/análogos & derivados , Muramidase/metabolismo , Animais , Ácido Aspártico , Galinhas , Dicroísmo Circular , Glutamatos , Concentração de Íons de Hidrogênio , Ligação Proteica , Estereoisomerismo , Perus
10.
J Biochem ; 78(3): 589-97, 1975 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5413

RESUMO

The binding constants of N-acetylglucosamine (G1cNAc) and its methyl alpha- and beta- glycosides to hen and turkey egg-white lysozymes [EC 3.2.1.17], in the latter of which Asp 101 is replaced by Gly, were determined at various pH values by measuring changes in the circular dichroic (DC) band at 295 nm. The binding of beta-methyl-G1cNAc to turkey and hen lysozymes perturbed the pK value of Glu 35 from 6.0 to 6.5, the pK value of Asp 52 from 3.5 to 3.9, and the pK value of Asp 66 from 1.3 to 0.7. In addition, perturbation of the pK value of Asp 101 from 4.4 to 4.0 was observed in the binding of this saccharide to hen lysozyme. The binding of alpha-methyl-GlcNAc to hen and turkey lysozymes perturbed the pK value of Glu 35 to the alkaline side by about 0.5 pH unit, the pK value of Asp 66 to the acidic side by about 0.5 pH unit, and the pK value (4.4) of an ionizable group to the acidic side by about 0.6 pH unit. The last ionizable group was tentatively assigned to Asp 48. The pK value of Asp 52 was not perturbed by the binding of this saccharide. The pH dependence curves for the binding of GlcNAc to hen and turkey lysozymes were very similar and it was suggested that Asp 48, in addition to Asp 66, Asp 52, and Glu 35, is perturbed by the binding of GlcNAc.


Assuntos
Acetilglucosamina , Glucosamina , Muramidase , Animais , Sítios de Ligação , Galinhas , Dicroísmo Circular , Clara de Ovo , Glucosamina/análogos & derivados , Concentração de Íons de Hidrogênio , Matemática , Muramidase/metabolismo , Ligação Proteica , Conformação Proteica , Especificidade da Espécie , Perus
11.
J Biochem ; 114(1): 76-82, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8407880

RESUMO

The structures of the N-linked oligosaccharides on recombinant human hepatocyte growth factor (rh-HGF) expressed by Chinese hamster ovary (CHO) cells were studied by two-dimensional sugar mapping. The oligosaccharides released from the glycopeptides by peptide: N-glycosidase F (PNGase F) treatment were tagged with 2-aminopyridine at the reducing ends. The alpha-chain was linked by biantennary, triantennary, and tetraantennary oligosaccharides, but the dominant oligosaccharides linking the beta-chain were biantennary (> 85%). There was no significant difference in oligosaccharide structures between the two glycosylation sites on each chain, that is, Asn263 and Asn371 on the alpha-chain, and Asn535 and Asn622 on the beta-chain. The linkage of sialic acid to the non-reducing terminal galactose was identified as NeuAc alpha(2-3) by 1H-NMR spectrometry. The structures of the N-linked oligosaccharides from rat HGF were also studied. Triantennary oligosaccharides were obtained from the alpha-chain and a biantennary oligosaccharide was obtained from the beta-chain. This result indicates that the alpha-chain is also linked by higher branched oligosaccharides than the beta-chain in rat HGF.


Assuntos
Fator de Crescimento de Hepatócito/química , Fígado/química , Oligossacarídeos/química , Aminopiridinas/química , Animais , Células CHO , Configuração de Carboidratos , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Cricetinae , Cricetulus , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes/química , Espectrometria de Fluorescência
12.
Histol Histopathol ; 10(2): 463-79, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7599442

RESUMO

The kinetics of two enzyme systems in situ that have been studied with real-time image analysis systems are reviewed in detail. The enzymes are a structurally-bound mitochondrial enzyme, succinate dehydrogenase (SDH) and a soluble cytoplasmic enzyme, lactate dehydrogenase (LDH). The image analysis system is used to capture successive images of a tissue section at constant time intervals whilst it is being incubated on a substrate-containing gel film. The increasing absorbances of the final reaction products in each cell are measured in the successive images as a function of incubation time. The absorbances of the formazan reaction products formed by SDH, for example, in sections of liver determined by such means increase linearly during the first minute of incubation, but non-linearly afterwards. The initial velocities of SDH in single hepatocytes in sections incubated on gel substrate films are calculated from the activities during the first 20 s of incubation. In contrast, the activities of LDH measured in various cell types, including hepatocytes, with the gel film technique increase nonlinearly during the first minute of incubation, but linearly for incubation times between 1 and 3 min. The initial velocities (vi) of LDH in single cells can be, calculated, however from the activities during the first interval, 10 s, of the image capturing sequence. Unfortunately, the experimental errors of the initial velocities of LDH determined in this way are relatively high. To overcome this problem, we have found empirically that the equations vi = a1oA and vi = v + a2oA enable reliable initial velocities (vi) of the LDH reaction in single cells of various types to be calculated using the data of the linear activities for incubation times between 1 and 3 min. Dependence of the initial velocities of the SDH and LDH reactions on substrate concentrations gave the Michaelis constants (Km) and maximum velocities (Vmax). The Km values determined in situ for SDH in hepatocytes and for LDH in various cell types with the gel film technique are in the same order of magnitude as the corresponding values determined biochemically. The constants a1, a2 and Km of LDH are characteristic for each cell type and seem to be related to the intracellular localization of the enzyme and to its ligand-binding rather than to the different isozyme compositions in various cell types.


Assuntos
Enzimas/metabolismo , L-Lactato Desidrogenase/metabolismo , Succinato Desidrogenase/metabolismo , Animais , Histocitoquímica , Humanos , Processamento de Imagem Assistida por Computador , Cinética
13.
Pancreas ; 13(3): 283-8, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8884850

RESUMO

The effect of a potent and long-acting bradykinin B2-receptor antagonist (HOE140) on acute pancreatitis induced by retrograde infusion of trypsin and taurocholate into the pancreatic duct was studied in rats. HOE140 was administered subcutaneously immediately before and 3 h after the induction of pancreatitis and the systemic blood pressure, ascites volume, serum amylase, 24-h survival rate, and pathology of the pancreas were evaluated. Plasma concentrations of bradykinin increased significantly 15 min after the induction of pancreatitis and decreased to basal levels at 90 min. HOE140 (0.1 mg/kg) alleviated hypotension developing immediately after the induction of pancreatitis and reduced the ascites volume. The 24-h survival rate in rats treated with 0.1 mg/kg HOE140 (70.3%) was significantly higher than that in controls (35.6%). Treatment with 0.01, 0.3, 1.0, and 3.0 mg/kg of HOE140, however, had no beneficial effect on the survival rate. Ascites volume, serum amylase, and pathology of the pancreas at 24 h were not improved by treatment with HOE140. These data suggest that HOE140 may improve the survival rate by maintaining hemodynamics in the early stage of experimental acute pancreatitis.


Assuntos
Antagonistas dos Receptores da Bradicinina , Bradicinina/análogos & derivados , Pancreatite/induzido quimicamente , Ácido Taurocólico , Doença Aguda , Amilases/sangue , Animais , Ascite , Pressão Sanguínea , Bradicinina/sangue , Bradicinina/farmacologia , Bradicinina/uso terapêutico , Hematócrito , Cinética , Masculino , Pâncreas/patologia , Pancreatite/patologia , Pancreatite/fisiopatologia , Ratos , Ratos Wistar , Tripsina
14.
Pancreas ; 15(4): 345-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9361087

RESUMO

To characterize the activation of pancreatic zymogens (trypsinogen, chymotrypsinogen, and proelastase 1) in acute pancreatitis, we studied the activation of pancreatic juice with porcine enteropeptidase in vitro, and then enzymatic activities and the generation of pancreatic stone protein (PSP) S1 form in pancreatic juice were investigated. Further, we determined immunoreactive trypsin, immunoreactive elastase 1, PSP, and alpha(2)-macroglobulin-trypsin complex-like substance (MTLS) levels in plasma to which the activated juice was added. In the present report, we demonstrate that the plasma MTLS level reflected the activation of pancreatic trypsinogen in pancreatic juice. Further, the generation of PSP S1 form was found at an early stage of activation. Therefore, the plasma MTLS level and the generation of PSP S1 form may offer new diagnostic information on the amounts of activated proteases and subsequently on the severity of acute pancreatitis.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Precursores Enzimáticos/metabolismo , Proteínas do Tecido Nervoso , Suco Pancreático/enzimologia , Suco Pancreático/metabolismo , Tripsina/metabolismo , alfa-Macroglobulinas/metabolismo , Animais , Proteínas de Ligação ao Cálcio/sangue , Proteínas de Ligação ao Cálcio/química , Quimotripsinogênio/metabolismo , Enteropeptidase/metabolismo , Precursores Enzimáticos/sangue , Humanos , Técnicas Imunoenzimáticas , Litostatina , Elastase Pancreática/sangue , Elastase Pancreática/metabolismo , Suínos , Tripsina/análise , Tripsina/sangue , Tripsinogênio/metabolismo , alfa-Macroglobulinas/análise
15.
Pancreas ; 15(4): 402-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9361095

RESUMO

To evaluate the effectiveness of exocrine function tests in diagnosing chronic pancreatitis (CP), we compared the sensitivity and specificity of duodenal intubation with tubeless tests. While the secretin test (ST) was necessary to diagnose CP, especially in noncalcified CP, and tubeless tests demonstrated insufficient sensitivity to diagnose CP, the combination assay of tubeless tests was specific enough to diagnose severe exocrine dysfunction. Our studies found the sensitivity of secretin testing to diagnose definite CP to be 87%. In patients with probable CP, 60% had mild exocrine insufficiency and 40% had normal function. The false-positive rate of the ST results in nonpancreatic diseases, except diabetes mellitus, was 5%. The correlation between morphological changes in endoscopic retrograde pancreatography (ERP) and exocrine function evaluated by ST was 74%. In patients with calcified CP, 81% had parallel results between ERP and the ST, but in noncalcified CP, 47% had parallel results. In patients with severe or moderate exocrine insufficiency demonstrated by ST, abnormally low levels were observed in 63% by N-benzoyl-L-tyrosyl-p-aminobenzoic acid (BT-PABA) test, 61% by fecal chymotrypsin test (FCT), and 44% by pancreatic amylase (PA). In patients with normal exocrine function demonstrated by ST, abnormally low levels were observed in 28% by BT-PABA test, 28% by FCT, and 10% by PA. A combination assay of BT-PABA test, FCT, and PA improved the specificity for diagnosing CP but not the sensitivity.


Assuntos
Testes de Função Pancreática/métodos , Pancreatite/diagnóstico , Ácido 4-Aminobenzoico , Amilases/metabolismo , Colangiopancreatografia Retrógrada Endoscópica , Doença Crônica , Quimotripsina/análise , Fezes/química , Humanos , Isoamilase/sangue , Pâncreas/diagnóstico por imagem , Pâncreas/metabolismo , Pancreatite/diagnóstico por imagem , Pancreatite/fisiopatologia , Fosfolipases A/sangue , Secretina , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Tripsina/sangue , Ultrassonografia , para-Aminobenzoatos
16.
Pancreas ; 17(3): 289-94, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9788544

RESUMO

The effects of a new benzodiazepine-derivative, cholecystokinin receptor antagonist, TS-941, on experimental acute pancreatitis were studied in rats. Hemorrhagic pancreatitis was induced by an infusion of a mixture of trypsin and taurocholate into the pancreatic duct. Edematous pancreatitis was induced by intraperitoneal injection of 40 microg/kg body weight of cerulein at 0 and 1 h after the start of the experiment. TS-941 (3 mg/kg) was injected subcutaneously immediately and 3 h after the induction of pancreatitis. In trypsin-taurocholate-induced pancreatitis, TS-941, with or without the synthetic trypsin inhibitor ONO-3403, had no beneficial effects on the survival rate, pancreatic wet weight, and serum pancreatic enzymes. In cerulein-induced pancreatitis, the treatment with TS-941 significantly reduced the increases of pancreatic wet weight and serum amylase and lipase. Plasma trypsinogen activation peptide (TAP) significantly rose 1 h after the first injection of cerulein. TS-941 inhibited the liberation of TAP in cerulein-induced pancreatitis. These results show that TS-941 is effective for prevention of cerulein-induced edematous pancreatitis. ONO-3403 has beneficial effects on trypsin-taurocholate-induced hemorrhagic pancreatitis, but the combination of TS-941 and ONO-3403 has no additive effect.


Assuntos
Benzodiazepinas/farmacologia , Pâncreas/efeitos dos fármacos , Pancreatite/prevenção & controle , Receptores da Colecistocinina/antagonistas & inibidores , Doença Aguda , Alilglicina/análogos & derivados , Alilglicina/farmacologia , Amilases/sangue , Animais , Benzamidinas/farmacologia , Ceruletídeo , Quimioterapia Combinada , Lipase/sangue , Masculino , Oligopeptídeos/sangue , Tamanho do Órgão/efeitos dos fármacos , Pancreatite/induzido quimicamente , Pancreatite/enzimologia , Ratos , Ratos Wistar , Ácido Taurocólico , Tripsina/metabolismo , alfa-Macroglobulinas/metabolismo
17.
Pancreas ; 20(4): 389-93, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10824694

RESUMO

Plasma and urine levels of trypsinogen activation peptides (TAP) reflect the severity of acute pancreatitis in experimental and clinical acute pancreatitis. In trypsin-taurocholate-induced pancreatitis in rats, the extrinsic bovine trypsin used for the induction of pancreatitis might influence on the TAP levels after induction of pancreatitis. The aim of the present study was to elucidate whether infused trypsin itself affects TAP levels in trypsin-taurocholate-induced pancreatitis. Rats were divided into three groups. In the pancreatitis group, acute pancreatitis was induced by a retrograde infusion of bovine trypsin and sodium taurocholate into the pancreatic duct. In the duct infusion group and peritoneal injection group, a mixture of bovine trypsin and trypsin inhibitor, ONO-3403, was infused into the pancreatic duct or the peritoneal cavity. Plasma and urine TAP concentration significantly increased in trypsin-taurocholate-induced pancreatitis but not in the duct infusion and peritoneal injection groups for 6 hours after the infusion of trypsin. Serum rat immunoreactive trypsin (IRT) and amylase significantly increased in the pancreatitis and duct infusion groups but not in the peritoneal injection group. Serum levels of bovine IRT in the pancreatitis group was significantly lower than those in duct infusion and peritoneal injection groups. In conclusion, an intraductal infusion of bovine trypsin itself into pancreatic duct does not influence the levels of plasma and urine TAP in trypsin-taurocholate-induced pancreatitis.


Assuntos
Pancreatite/induzido quimicamente , Peptídeos/sangue , Peptídeos/urina , Ácido Taurocólico/administração & dosagem , Tripsina/farmacologia , Tripsinogênio/metabolismo , Doença Aguda , Amilases/sangue , Animais , Bovinos , Ativação Enzimática , Injeções Intraperitoneais , Masculino , Ductos Pancreáticos/efeitos dos fármacos , Ratos , Ratos Wistar , Tripsina/administração & dosagem
18.
Pancreas ; 22(1): 24-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11138966

RESUMO

Trypsinogen activation peptide (TAP) is a useful marker of severe acute pancreatitis. However, it is sometimes difficult to detect an elevation of plasma TAP in patients with acute pancreatitis because TAP is rapidly cleared from plasma. Therefore, urine TAP has been evaluated to provide an accurate prediction of the outcome of pancreatitis. In the present study, we examined the time course of plasma and urine TAP simultaneously after induction of taurocholate-induced pancreatitis in rats. Plasma TAP levels peaked at 1 hour after the induction of pancreatitis and then gradually decreased, but was still higher than prepancreatitis levels at 48 hours. Significant increases in urine TAP levels were seen at 0-6, 6-12, and 30-36 hours after induction of pancreatitis. The peak level of urine TAP output and TAP/creatinine ratio was observed at 6-12 and 30-36 hours, respectively. Urine TAP concentration showed a significant correlation with both urine TAP/creatinine ratio and TAP output in urine (p < 0.01). In conclusion, plasma TAP increased immediately after the induction of pancreatitis, but excretion of TAP into urine was delayed several hours in taurocholate-induced pancreatitis in rats. The measurement of urine TAP concentration alone sufficiently can reflect the amount of TAP liberated in the pancreas at initial stage of acute pancreatitis.


Assuntos
Oligopeptídeos/urina , Pancreatite/urina , Ácido Taurocólico/toxicidade , Doença Aguda , Animais , Creatinina/urina , Técnicas Imunoenzimáticas , Masculino , Oligopeptídeos/sangue , Pancreatite/sangue , Pancreatite/induzido quimicamente , Ratos , Ratos Wistar , Fatores de Tempo
19.
Pancreas ; 10(3): 306-13, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7542773

RESUMO

Trypsinogen activation peptide (TAP) concentration and alpha 2-macroglobulin-trypsin complex (alpha 2M-T) activity were measured in two experimental models of acute pancreatitis in rats to evaluate the significance of activation of trypsinogen in acute pancreatitis. TAP concentration and alpha 2M-T activity in serum rose significantly in trypsin-taurocholate-induced hemorrhagic acute pancreatitis, while in cerulein-induced edematous acute pancreatitis they did not rise in spite of a similar increase in immunoreactive trypsin. When rats in trypsin-taurocholate-induced pancreatitis were treated by protease inhibitor (FUT-175; nafamostat mesilate; FUT group), alpha 2M-T activity in serum was significantly lower than that in nontreated controls (mean +/- SEM, 20.8 +/- 1.43 U/L in the FUT group vs 79.1 +/- 24.5 in controls; p < 0.01). The survival rate at 24 h was significantly improved in the FUT group compared with the controls (70 vs 43%; p < 0.05). The increase in TAP concentration in the FUT group was similar to that in controls. The TAP concentration in pancreatic tissue at 24 h was significantly (p < 0.01) lower in the survival group (7.8 +/- 0.8 ng/ml) than in the lethal group (25.9 +/- 3.7 ng/ml). Activation of trypsinogen and its subsequent enzyme activity play an important role in the evolution of severe acute pancreatitis.


Assuntos
Pancreatite/metabolismo , Tripsinogênio/metabolismo , Doença Aguda , Animais , Benzamidinas , Ceruletídeo , Modelos Animais de Doenças , Guanidinas/farmacologia , Masculino , Oligopeptídeos/sangue , Oligopeptídeos/metabolismo , Pancreatite/etiologia , Proglumida/análogos & derivados , Proglumida/farmacologia , Inibidores de Proteases/farmacologia , Ratos , Ratos Wistar , Receptores da Colecistocinina/antagonistas & inibidores , Ácido Taurocólico , Tripsina/sangue , Tripsina/metabolismo , alfa-Macroglobulinas/metabolismo
20.
Pancreas ; 16(3): 323-8, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9548674

RESUMO

Based primarily on our experience, we review current problems on etiology, pathogenesis, classification, diagnosis, and treatment of chronic pancreatitis. Much of the confusion and difficulty associated with chronic pancreatitis originates from the relative inaccessibility of this organ. A lack of specific and sensitive markers that are suitable for the follow-up of a long natural course of chronic pancreatitis also hinders our understanding of this disease. The resolution of the present imaging tests, even by the latest technology, is not good enough to detect early changes of the pancreas. In the past 10 years, several subgroups of patients with alcoholic and idiopathic pancreatitis have been identified based on the long-term follow-up study. Pain disappeared spontaneously in many patients during the course of the disease, but its mechanism is still poorly understood. Removal of pancreatic stones and protein plugs by chemical, endoscopic, or extracorporeal shock-wave therapy has been tried with some success, but their clinical values remain to be established. Attempts have been made to understand the etiology and pathogenesis of chronic pancreatitis at molecular levels. This approach, together with a prospective follow-up of patients, will improve our understanding on chronic pancreatitis.


Assuntos
Pancreatite , Doenças Autoimunes , Cálculos , Doença Crônica , Humanos , Dor , Pancreatopatias , Pancreatite/classificação , Pancreatite/diagnóstico , Pancreatite/etiologia , Pancreatite/terapia
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