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2.
Artículo en Inglés | MEDLINE | ID: mdl-26603595

RESUMEN

This longitudinal descriptive study examined whether rectal cancer patients report changes in health-related quality of life (HRQOL) over a 6-month period after different types of sphincter-saving surgery (SSS): intersphincteric resection (ISR), ultra-low anterior resection (ULAR) and low anterior resection (LAR). It also compares HRQOL among the three groups of patients. Seventy-three patients from two hospitals in Japan completed questionnaires on HRQOL and defecation symptoms immediately before surgery and 1 and 6 months afterwards. Results showed that ISR patients had significantly worse HRQOL scores than ULAR and LAR patients and more defecation symptoms that persisted during the 6 months post-SSS. Thus, patients undergoing ISR require psychological and social support, including skills in competent self-management, during the early post-operative period. Furthermore, defecation problems substantially influence HRQOL. The first month post-SSS is particularly challenging. The assumption that HRQOL is better after SSS compared to living with a permanent stoma might not be valid.


Asunto(s)
Calidad de Vida , Neoplasias del Recto/cirugía , Actividades Cotidianas , Canal Anal/cirugía , Análisis de Varianza , Defecación/fisiología , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Tratamientos Conservadores del Órgano/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/fisiopatología , Estudios Prospectivos , Neoplasias del Recto/fisiopatología , Autocuidado , Apoyo Social
3.
Diabetologia ; 49(7): 1647-55, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16752183

RESUMEN

AIMS/HYPOTHESIS: Metformin is widely used as a hypoglycaemic reagent for type 2 diabetes. While the reduction of hepatic gluconeogenesis is thought to be a key effect, the detailed molecular mechanism of action of metformin remains to be elucidated. To gain insight into this, we performed a global gene expression profiling study. MATERIALS AND METHODS: We performed DNA microarray analysis to study global gene expression in the livers of obese diabetic db/db mice 2 h after a single administration of metformin (400 mg/kg). RESULTS: This analysis identified 14 genes that showed at least a 1.5-fold difference in expression following metformin treatment, including a reduction of glucose-6-phosphatase gene expression. The mRNA levels of glucose-6-phosphatase showed one of the best correlations with blood glucose levels among 12,000 genes. Enzymatic activity of glucose-6-phosphatase was also reduced in metformin-treated liver. Moreover, intensive analysis of the expression profile revealed that metformin effected significant alterations in gene expression across at least ten metabolic pathways, including those involved in glycolysis-gluconeogenesis, fatty acid metabolism and amino acid metabolism. CONCLUSIONS/INTERPRETATION: These results suggest that reduction of glucose-6-phosphatase activity, as well as suppression of mRNA expression levels of this gene, in liver is of prime importance for controlling blood glucose levels in vivo, at least at early time points after metformin treatment. Our results also suggest that metformin not only affects expression of specific genes, but also alters the expression level of multiple genes linked to the metabolic pathways involved in glucose and lipid metabolism in the liver.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hígado/efectos de los fármacos , Metformina/uso terapéutico , Análisis de Secuencia por Matrices de Oligonucleótidos , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/genética , Relación Dosis-Respuesta a Droga , Expresión Génica/efectos de los fármacos , Glucosa-6-Fosfatasa/metabolismo , Hipoglucemiantes/uso terapéutico , Hígado/metabolismo , Masculino , Redes y Vías Metabólicas , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Modelos Biológicos
4.
J Pharm Pharmacol ; 50(10): 1155-60, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9821663

RESUMEN

Ginsenoside Rb1 from Panax ginseng root is transformed into compound K via ginsenosides Rd and F2 by intestinal bacterial flora. Among 31 defined intestinal strains from man, only Eubacterium sp. A-44 transformed ginsenoside Rb1 into compound K via ginsenoside Rd. The ginsenoside Rb1-hydrolysing enzyme isolated from Eubacterium sp. A-44 was identical to a previously purified geniposide-hydrolysing beta-D-glucosidase. When ginsenoside Rb1 (200 mg kg-1) was administered orally to germ-free rats, neither compound K nor any other metabolite was detected in the plasma, intestinal tract or cumulative faeces 7 or 15 h after administration. Most of the ginsenoside Rb1 administered was recovered from the intestinal tract, especially the caeca, and cumulative faeces indicating poor absorption of ginsenoside Rb1. When ginsenoside Rb1 was administered orally to gnotobiote rats mono-associated with Eubacterium sp. A-44, a significant amount of compound K was detected in the plasma and considerable amounts were found in the caecal contents and cumulative faeces 7 and 15 h after administration. A small amount of ginsenoside Rb1 was detected in the caecal contents only 7 h after administration. These results indicate that orally administered ginsenoside Rb1 is poorly absorbed from the gut but that its metabolite compound K, produced by ginsenoside Rb1-hydrolysing bacteria such as Eubacterium sp. A-44 in the lower part of intestine, is absorbed.


Asunto(s)
Fármacos del Sistema Nervioso Central/metabolismo , Eubacterium/metabolismo , Intestinos/microbiología , Panax , Plantas Medicinales , Saponinas/sangre , Saponinas/metabolismo , Triterpenos/sangre , Administración Oral , Animales , Biotransformación , Fármacos del Sistema Nervioso Central/farmacología , Ginsenósidos , Humanos , Hidrólisis , Absorción Intestinal , Mucosa Intestinal/metabolismo , Masculino , Panax/química , Ratas , Ratas Wistar , Saponinas/farmacología
6.
Biol Pharm Bull ; 21(3): 245-9, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9556154

RESUMEN

Enzyme immunoassay (EIA) for the determination of compound K (C-K), a major metabolite of ginsenoside Rb1 (G-Rb1) from Panax ginseng root by intestinal bacterial flora, was explored. Bovine serum albumin (BSA) was coupled to the C-26 position on the unsaturated side chain of C-K. Beta-D-galactosidase was introduced at the C-26 position of the saturated side chain. Antiserum, obtained by immunization of rabbits with C-K-BSA conjugate, possessed high affinity and specificity toward C-K. The EIA for C-K by the double antibody method was established in the range of 0.1--100 ng/tube. Plasma C-K after the oral administration of C-K and G-Rb1 to rats was determined by the established EIA. C-K was rapidly absorbed from the gastrointestinal tract after the administration, then slowly decreased. On the other hand, C-K appeared late and was retained for a long period of time in the plasma after the administration of G-Rb1, which itself is hardly absorbed.


Asunto(s)
Intestinos/microbiología , Saponinas/metabolismo , Administración Oral , Animales , Femenino , Ginsenósidos , Técnicas para Inmunoenzimas , Masculino , Conejos , Ratas , Ratas Wistar , Saponinas/administración & dosificación
7.
Appl Environ Microbiol ; 62(4): 1491, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16535302

RESUMEN

Volume 61, no. 9, p. 3209, column 2, line 23: "L22165" should read "L22516." [This corrects the article on p. 3208 in vol. 61.].

8.
Appl Environ Microbiol ; 61(9): 3208-15, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7574629

RESUMEN

The gene coding for a novel esterase which stereoselectively hydrolyzes the (+)-trans (1R,3R) stereoisomer of ethyl chrysanthemate was cloned from Arthrobacter globiformis SC-6-98-28 and overexpressed in Escherichia coli. The cellular content of the active enzyme reached 33% of the total soluble protein in the recombinant E. coli JM105 cells and 5.6 g/liter of culture by high-density cell cultivation. The hydrolytic activity of the recombinant E. coli cells for ethyl chrysanthemate reached 605 mumol of chrysanthemic acid per min per g of dry cells, which is approximately 2,500-fold higher than that of A. globiformis cells. The stereoselective hydrolysis by the recombinant E. coli cells was efficient at substrate concentrations of up to 40% by removing the produced chrysanthemic acid by ultrafiltration. The (+)-trans-chrysanthemic acid produced had 100% optical purity. The amino acid sequence of the esterase was found to be similar to that of several class C beta-lactamases, D,D-carboxypeptidase, D-aminopeptidase, 6-aminohexanoate-dimer hydrolase, and Pseudomonas esterase. The sequence comparison also suggested that the Ser-X-X-Lys motif in the esterase was at the active site of the enzyme.


Asunto(s)
Arthrobacter/enzimología , Arthrobacter/genética , Esterasas/genética , Esterasas/metabolismo , Insecticidas/metabolismo , Piretrinas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Sondas de ADN/genética , Escherichia coli/genética , Expresión Génica , Genes Bacterianos , Insecticidas/química , Datos de Secuencia Molecular , Plásmidos/genética , Piretrinas/química , Homología de Secuencia de Aminoácido , Estereoisomerismo
9.
Proc Natl Acad Sci U S A ; 92(19): 8579-83, 1995 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-7567978

RESUMEN

Human ciliary neurotrophic factor (hCNTF), which promotes the cell survival and differentiation of motor and other neurons, is a protein belonging structurally to the alpha-helical cytokine family. hCNTF was subjected to three-dimensional structure modeling and site-directed mutagenesis to analyze its structure-function relationship. The replacement of Lys-155 with any other amino acid residue resulted in abolishment of neural cell survival activity, and some of the Glu-153 mutant proteins had 5- to 10-fold higher biological activity. The D1 cap region (around the boundary between the CD loop and helix D) of hCNTF, including both Glu-153 and Lys-155, was shown to play a key role in the biological activity of hCNTF as one of the putative receptor-recognition sites. In this article, the D1 cap region of the 4-helix-bundle proteins is proposed to be important in receptor recognition and biological activity common to alpha-helical cytokine proteins reactive with gp130, a component protein of the receptors.


Asunto(s)
Ganglios Espinales/efectos de los fármacos , Factores de Crecimiento Nervioso/farmacología , Proteínas del Tejido Nervioso/farmacología , Neuronas/efectos de los fármacos , Aminoácidos/química , Secuencia de Bases , Supervivencia Celular/efectos de los fármacos , Factor Neurotrófico Ciliar , Citocinas/genética , Análisis Mutacional de ADN , Relación Dosis-Respuesta a Droga , Ganglios Espinales/citología , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Factores de Crecimiento Nervioso/química , Factores de Crecimiento Nervioso/genética , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/genética , Estructura Terciaria de Proteína , Relación Estructura-Actividad
10.
Acta Med Okayama ; 49(4): 195-200, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7502679

RESUMEN

Although a strong association has been established between chronic Helicobacter pylori infection and peptic ulcers, the role of H. pylori is not necessarily causative because there are many patients infected with H. pylori who do not develop peptic ulcer. Therefore, we studied the relationship between the gastric mucosal environment and the development of peptic ulcers. We examined 165 endoscopic biopsy specimens from the gastric mucosa of 33 patients with peptic ulcers using the 5-point gastric biopsy method. The follow-up biopsies done within 3 weeks were well correlated with the first biopsy samples. We also reviewed the clinicohistopathological findings of 2250 endoscopic biopsy specimens from 450 patients with active gastric and/or duodenal ulcers. Over 90% of the patients with duodenal ulcer, with or without gastric ulcer, had no fundic gland atrophy, and a high incidence of intestinal metaplasia and pyloric mucosal atrophy was found in the patients with gastric ulcer. These findings suggest that patients with concomitant active gastric and duodenal ulcers exhibit severe atrophic changes in the antral mucosa but not in the fundic mucosa.


Asunto(s)
Mucosa Gástrica/patología , Úlcera Péptica/patología , Adulto , Anciano , Atrofia/epidemiología , Biopsia/métodos , Gastroscopía/métodos , Humanos , Incidencia , Metaplasia/epidemiología , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios Retrospectivos
11.
Nihon Geka Gakkai Zasshi ; 96(6): 402-5, 1995 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-7666857

RESUMEN

A 76-year-old man visited our clinic with chest radiographic evidence of a coin lesion in the right middle lung. Chest CT demonstrated an infiltrative shadow mainly in the S4 segment. Lymphoproliferative disorders were suggested by transbronchial lung biopsy. Middle lobectomy was performed. Pathological study showed massive proliferation of mature lymphocytes. Immunoperoxidase studies could not demonstrate a neoplastic monoclonal process. Pseudolymphoma was diagnosed. High molecular weight DNAs were extracted from frozen specimens. Whether genes of immunoglobulins and T-cell receptors were rearranged was investigated using DNA probes against JH and TCR beta-1 receptor gene. One rearranged band was found in the JH chain. No rearranged band appeared in TCR beta-1 chain. B cell lymphoma was diagnosed instead of pseudolymphoma.


Asunto(s)
Reordenamiento Génico de Cadena Pesada de Linfocito B , Neoplasias Pulmonares/genética , Linfoma de Células B/genética , Anciano , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirugía , Linfoma de Células B/diagnóstico , Linfoma de Células B/cirugía , Masculino , Neumonectomía
12.
J Clin Endocrinol Metab ; 80(6): 1929-33, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7775643

RESUMEN

18 beta-Glycyrrhetinic acid (GA) has been thought to be one of the major metabolites that causes licorice-induced pseudoaldosteronism. However, we found no difference in the blood level of GA between the patients with and without pseudoaldosteronism. We measured the blood concentration of 3 beta-D-(monoglucuronyl)18 beta-glycyrrhetinic acid (3MGA), another metabolite of 3 beta-D-diglucuronyl-18 beta-glycyrrhetinic acid (glycyrrhizin), by high performance liquid chromatography and found an increased concentration of 3MGA in 10 patients with licorice-induced pseudoaldosteronism, but not in 11 patients without pseudoaldosteronism. To investigate whether 3MGA can inhibit 11 beta-hydroxysteroid dehydrogenase, we incubated rat renal microsome with or without 3MGA and measured the conversion rate of [3H]cortisol to [3H]cortisone. 3MGA was found to be a potent inhibitor of 11 beta-hydroxysteroid dehydrogenase, allowing cortisol to exert its full mineralocorticoid effects. These results suggest that licorice-induced pseudoaldosteronism is due to an increased concentration of 3MGA, but not GA, in the circulating blood of these patients.


Asunto(s)
Ácido Glicirretínico/análogos & derivados , Glycyrrhiza/metabolismo , Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , Hiperaldosteronismo/inducido químicamente , Plantas Medicinales , 11-beta-Hidroxiesteroide Deshidrogenasas , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Femenino , Ácido Glicirretínico/efectos adversos , Ácido Glicirretínico/sangre , Ácido Glicirretínico/farmacología , Humanos , Hidrocortisona/metabolismo , Hiperaldosteronismo/diagnóstico , Riñón/ultraestructura , Masculino , Microsomas/enzimología , Persona de Mediana Edad , NADP/farmacología
13.
Protein Eng ; 7(3): 435-43, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8177893

RESUMEN

Mouse monoclonal anti-human IL-2 receptor antibody (B-B10) inhibits IL-2-dependent human T-cell proliferation. It has been used in clinical trials in the transplantation field and promising results are being accumulated. Mouse B-B10 antibody was humanized by grafting all CDRs and some framework amino acid residues onto human antibodies, KAS for VH and PAY for V kappa. Nine humanized B-B10s with differently grafted framework residues were constructed and assessed for their biological activities. One of these humanized B-B10, M5, showed nearly the same activity as the mouse B-B10. The 49th residue of V kappa was demonstrated to play a crucial role in the antigen-antibody interaction by 3-D structure analysis with a computer modeling system.


Asunto(s)
Anticuerpos Monoclonales/química , Ingeniería Genética , Receptores de Interleucina-2/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/genética , Anticuerpos Monoclonales/metabolismo , Secuencia de Bases , Clonación Molecular , Simulación por Computador , ADN/química , ADN/genética , Humanos , Región Variable de Inmunoglobulina/genética , Ratones , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa , Homología de Secuencia , Relación Estructura-Actividad , Transfección
14.
J Pharm Pharmacol ; 46(2): 135-7, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8021802

RESUMEN

Gnotobiote rats were prepared by infecting germ-free rats with Eubacterium sp. strain GLH, a human intestinal bacterium capable of hydrolysing glycyrrhizin to 18 beta-glycyrrhetic acid. Their faeces and caecal contents showed glycyrrhizin-hydrolysing activities (31.7 and 31.3 pmol min-1 (mg protein)-1, respectively) similar to those (81.0 and 39.9 pmol min-1 (mg protein)-1, respectively) of conventional rats, although there was no detectable activity in germ-free rats. When glycyrrhizin (100 mg kg-1) was orally administered to conventional, germ-free and gnotobiote rats, no glycyrrhizin could be detected in plasma 4 or 17 h after the administration, using EIA and HPLC assays. Plasma 18 beta-glycyrrhetic acid was not detected 4 or 17 h after the administration of glycyrrhizin to germ-free rats nor could this compound be detected in caecal contents or in the faeces. However, 18 beta-glycyrrhetic acid (0.6-2.6 nmol mL-1) was detected in plasma of the conventional and the gnotobiote rats 4 and 17 h after the administration, and the caecal contents after 4 h and the cumulative faeces up to 17 h of the conventional and the gnotobiote rats contained considerable amounts of 18 beta-glycyrrhetic acid. These findings indicate that orally administered glycyrrhizin is poorly absorbed from the gut, but is hydrolysed to 18 beta-glycyrrhetic acid by intestinal bacteria such as E. sp. strain GLH, and the resulting 18 beta-glycyrrhetic acid is absorbed.


Asunto(s)
Ciego/metabolismo , Ciego/microbiología , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/metabolismo , Absorción Intestinal/fisiología , Administración Oral , Animales , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Eubacterium/fisiología , Heces/microbiología , Ácido Glicirretínico/administración & dosificación , Ácido Glicirrínico , Humanos , Hidrólisis , Técnicas para Inmunoenzimas , Masculino , Radioinmunoensayo , Ratas , Ratas Endogámicas , Ratas Wistar , Streptococcus/fisiología
15.
Biochemistry ; 32(20): 5327-31, 1993 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-8499437

RESUMEN

Although it is widely recognized that many proteins contain discrete functional domains, it is less certain whether smaller, less obviously discrete, units of structure will retain their specific function when transplanted into a different context. The observation that the potent inflammatory cytokine human interleukin 1 beta has the same overall structure as soybean trypsin inhibitor (STI) (Kunitz) prompted us to replace a tight turn in the cytokine sequence with the large loop in soybean trypsin inhibitor that binds to the active site of trypsin. Wild-type interleukin 1 beta (IL-1 beta) is highly resistant to proteolysis, but the chimeric STI/IL is specifically cleaved by trypsin, apparently in the inserted loop. Other chimeric interleukins have also been constructed, by replacing the same tight turn with inhibitory loops from other protein protease inhibitors: turkey ovomucoid inhibitor (TOI), a chymotrypsin inhibitor, and alpha 1-antitrypsin (AT), an elastase inhibitor. Although these loops come from proteins not related structurally to interleukin 1, they confer specific protease sensitivity or inhibition on the chimeric cytokine. The cytokine properties of these chimeric interleukins have also been evaluated. The chimeras formed from human IL-1 beta and all inhibitory loops tested bind to the interleukin 1 receptor with reasonable affinity. The typical cellular effects of IL-1, however, are not observed with all the recombinant proteins, thus confirming that receptor binding and signal transduction can be uncoupled. When these results are taken together with the results of site-directed mutagenesis of IL-1, reported in this paper and elsewhere, they allow the receptor and intracellular transduction sites on the protein to be mapped in detail.


Asunto(s)
Interleucina-1/fisiología , Inhibidores de Proteasas/química , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Ovomucina/antagonistas & inhibidores , Inhibidores de Proteasas/metabolismo , Receptores de Interleucina-1/metabolismo , Transducción de Señal/fisiología , Relación Estructura-Actividad , Inhibidor de Tripsina Pancreática de Kazal/química , Pavos , alfa 1-Antitripsina/química
16.
Liver ; 13(1): 10-4, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8096055

RESUMEN

The expression of intercellular adhesion molecule-1 (ICAM-1) on the hepatocyte membrane was studied in 27 patients with chronic hepatitis B and C (CHB, CHC) by immunostaining using a monoclonal antibody. ICAM-1 was expressed focally in a honeycomb-like pattern by hepatocytes in livers of 26/27 patients. The degree of ICAM-1 expression was closely related to the ALT level and the histological grade of liver damage. Abundant cytotoxic T cells (CD8+, CD11b-) were found in ICAM-1-positive areas of the liver. Zones of focal necrosis contained both ICAM-1-positive hepatocytes and cytotoxic T cells. The expression of ICAM-1 was decreased in 4/6 CHB patients after interferon-alpha therapy. No relationship between the degree of hepatocyte ICAM-1 expression and viral replication markers (DNA polymerase activity and the presence of HBcA in the liver) was observed in patients with CHB. In addition, no positive correlation was found between the distribution of ICAM-1-positive hepatocytes and HBcAg-positive hepatocytes. These results suggest that ICAM-1 may play an important role in the pathogenesis of hepatocellular injury mediated by cytotoxic T cells in CHB and CHC.


Asunto(s)
Antígenos CD/genética , Moléculas de Adhesión Celular/genética , Hepatitis B/metabolismo , Hepatitis C/metabolismo , Hepatitis Crónica/metabolismo , Hígado/metabolismo , Membrana Celular/química , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Molécula 1 de Adhesión Intercelular , Hígado/ultraestructura , Linfocitos T Citotóxicos/inmunología
17.
Protein Eng ; 6(1): 19-27, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8433967

RESUMEN

The solution structure of the 38 amino acid C-terminal region of the precursor for the HPLC-6 antifreeze protein from winter flounder has been investigated with molecular dynamics using the AMBER software. The simulation for the peptide in aqueous solution was carried out at a constant temperature of 0 degree C and at atmospheric pressure. The simulation covered 120 ps and the results were analyzed based on data sampled upon reaching a stable equilibrium phase. Information has been obtained on the quality of constant temperature and pressure simulations, the solution structure and dynamics, the hydrogen bonding network, the helix stabilizing role of terminal charges and the interaction with the surrounding water molecules. The Lys18-Glu22 interactions and the terminal charged residues are found to stabilize a helical structure with the side chains of Thr2, Thr13, Thr24 and Thr35 equally spaced on one side of the helix. The spacing between oxygen atoms in the hydroxyl group of the threonine side chains exhibits fluctuations of the order of 2-3 A during the 120 ps of simulation, but values simultaneously close to the repeat distance of 16.6 A between oxygen atoms along the [0112] direction in ice are observed. Furthermore, two engineered variants were studied using the same simulation protocol.


Asunto(s)
Glicoproteínas/química , Fragmentos de Péptidos/química , Secuencia de Aminoácidos , Animales , Proteínas Anticongelantes , Dicroismo Circular , Simulación por Computador , Lenguado , Congelación , Enlace de Hidrógeno , Datos de Secuencia Molecular , Conformación Proteica , Ingeniería de Proteínas , Estructura Secundaria de Proteína , Programas Informáticos , Soluciones/química
19.
Chem Pharm Bull (Tokyo) ; 40(2): 314-7, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1606629

RESUMEN

Enzyme immunoassay (EIA) of ginsenoside Rb1 (GRb1), one of the glucosides of protopanaxadiol from Panax ginseng, was explored. A carrier protein (bovine serum albumin (BSA)) was coupled to the C-26 position on the unsaturated side chain of the protopanaxadiol moiety to prepare the immunogen. In order to perform bridge heterologous EIA, a label (beta-D-galactosidase) was introduced at C-26 of the saturated side chain to obtain labeled antigen. Anti-GRb1 antisera were elicited in rabbits by immunization with GRb1-BSA conjugate (9). The double antibody method (with goat anti-rabbit IgG antiserum) was used to separate the bound and free GRb1-beta-Gal. A satisfactory standard curve for EIA of GRb1 was obtained in the range of 0.04-10 ng/tube. In a comparison of the assay results obtained by EIA and HPLC, the linear regression equation and correlation coefficient for the two methods were y (EIA) = 9.18x(HPLC)-0.033 and 0.98, respectively. The anti-GRb1 antiserum cross-reacted with GRb2 (21.8%) and GRc (10.6%), which are also constituents of Panax ginseng.


Asunto(s)
Panax/química , Plantas Medicinales , Saponinas/análisis , Animales , Cromatografía Líquida de Alta Presión , Reacciones Cruzadas , Ginsenósidos , Técnicas para Inmunoenzimas , Espectroscopía de Resonancia Magnética , Conejos , Saponinas/inmunología , Albúmina Sérica Bovina/química
20.
Radiology ; 182(2): 337-42, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1732946

RESUMEN

The authors reviewed 46 cases of idiopathic pulmonary fibrosis with usual interstitial pneumonia (UIP), correlating findings on high-resolution computed tomographic (HRCT) scans with findings in specimens obtained at open lung biopsy and autopsy. The following HRCT findings were observed: (a) an accumulation of small cystic spaces with thick walls, (b) air bronchiolograms within areas of intense lung attenuation, (c) rugged pleural surfaces, (d) irregularly thickened pulmonary vessels, (e) bronchial wall thickening, and (f) slightly increased lung attenuation. Macroscopic honeycombing correlating with small cystic spaces was demonstrated at HRCT and pathologic examination. Air bronchiolograms in the areas of intense lung attenuation (ie, microscopic honeycombing) corresponded to dilated bronchioles (greater than 1 mm in diameter) with fibrosis. Irregularly thickened vessels and bronchial walls and irregular pleural surfaces were the result of fibrosis in the periphery of the secondary pulmonary lobules. Areas of slightly increased lung attenuation seen on the HRCT scans correlated with patchy alveolar septal fibrosis or inflammation. The authors conclude that microscopic honeycombing and a perilobular distribution in UIP may be clearly identified with HRCT.


Asunto(s)
Fibrosis Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Biopsia , Bronquios/patología , Broncografía , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Masculino , Persona de Mediana Edad , Fibrosis Pulmonar/patología , Tomografía Computarizada por Rayos X/métodos
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