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1.
J Hosp Infect ; 117: 147-156, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34562548

RESUMEN

BACKGROUND: The impact of the coronavirus disease (COVID-19) pandemic on antimicrobial resistance (AMR) is a major concern. AIM: To compare the number of patients and isolation rate of antimicrobial-resistant bacteria before and after the beginning of the COVID-19 pandemic using the comprehensive national surveillance data. METHODS: We utilized comprehensive surveillance data, collected in the Japan Nosocomial Infections Surveillance programme, which included a total of 16.7 million samples of 5.9 million tested patients from >1300 hospitals. We compared the number of patients and isolation rate of five bacteria between 2019 and 2020, including antimicrobial-susceptible and -resistant bacteria of Staphylococcus aureus, Streptococcus pneumoniae, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. FINDINGS: The number of patients and isolation rate of S. aureus and meticillin-resistant S. aureus decreased slightly; those of S. pneumoniae and penicillin-resistant S. pneumoniae decreased by 60%; and those of third-generation cephalosporin-resistant K. pneumoniae increased. The isolation rate of the remaining bacteria apparently increased, although the number of patients decreased. This was due to a substantial decrease in the total number of tested patients (the denominator of the isolation rate), which was larger than that of the number of patients (the numerator of the isolation rate). Consistent results were obtained when the same data were re-aggregated using the procedure of the World Health Organization Global Antimicrobial Resistance Surveillance System, demonstrating the general importance of this problem. CONCLUSION: Surveillance data during the COVID-19 pandemic must be carefully interpreted based on examination of the numerator, denominator and background factors that affect the denominator.


Asunto(s)
Antiinfecciosos , COVID-19 , Staphylococcus aureus Resistente a Meticilina , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana , Humanos , Pruebas de Sensibilidad Microbiana , Pandemias , SARS-CoV-2 , Staphylococcus aureus
2.
J Hosp Infect ; 99(3): 325-331, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29549049

RESUMEN

BACKGROUND: The Japanese government adopted a national action plan on antimicrobial resistance, which aims to reduce drug-resistant pathogens and antimicrobial use. A point-prevalence survey (PPS) is a useful surveillance method to gain information about hospital epidemiology; however, no multi-centre PPS has previously been performed in Japan. AIM: To investigate general information about hospital epidemiology, healthcare-associated infections (HCAIs), and antimicrobial use in multiple Japanese university hospitals. METHODS: In July 2016, a multi-centre PPS was conducted using a standardized protocol at four university hospitals in Japan. FINDINGS: A total of 3199 patients were included. Median age and duration of hospital stay were 64 years and 10 days, respectively. A total of 246 (7.7%; 95% confidence interval (CI): 6.8-8.7) patients had 256 active HCAIs, and 933 (29.2%; 95% CI: 27.6-30.8) patients received 1318 antimicrobials. Pneumonia and gastrointestinal system infection were the most common HCAIs (N = 42, 16.4%), and Enterobacteriaceae (N = 49, 30.8%) were the predominant causative organisms. Carbapenems (N = 52, 17.8%), anti-MRSA medications, and cephems with antipseudomonal activity were the most frequently prescribed antimicrobials for HCAIs. As surgical prophylaxis, 46 of 278 antimicrobials (16.5%) were administered orally. Proportions of HCAI and antimicrobial use in each hospital ranged from 4.8% to 9.5% and 19.3%-35.0%, respectively. CONCLUSION: This multi-centre PPS recorded detailed HCAI data and distinct antimicrobial use in Japanese university hospitals. Further surveillance is necessary to reduce HCAIs and formulate feasible plans to achieve the national action plan on antimicrobial resistance.


Asunto(s)
Antibacterianos/uso terapéutico , Infección Hospitalaria/epidemiología , Utilización de Medicamentos , Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/aislamiento & purificación , Hospitales Universitarios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Japón , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Adulto Joven
3.
Neuroscience ; 289: 1-8, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25592422

RESUMEN

Although the neural correlates that underlie abdominal pain have been investigated, so-called brain processes involved in modulating "gut feelings" remain unclear. In the current study, we used electrointestinography (EIG) to measure intestinal activity of healthy humans at rest. EIG measured myoelectrical activity of intestinal smooth muscles from the abdominal surface and was simultaneously conducted along with brain activity measurement using functional magnetic resonance imaging (fMRI). Correlations between the frequency powers of EIG and fMRI signals during 30min of rest were then examined to elucidate gut-brain interactions. Neural activity correlating with 0.14- to 0.21-Hz EIG (suggested to reflect intestinal activity) was observed in the right anterior and middle insula. Moreover, this EIG frequency band correlated with anxiety scores along with resting-state functional connectivity between the insula and dorsal anterior cingulate cortex. These findings suggest that the insular cortex could be the core region involved in central visceral processes associated with subjective feelings.


Asunto(s)
Encéfalo/fisiología , Intestinos/fisiología , Adulto , Ansiedad/fisiopatología , Mapeo Encefálico , Electrodiagnóstico/métodos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Músculo Liso/fisiología , Escalas de Valoración Psiquiátrica , Descanso , Adulto Joven
4.
Placenta ; 32(8): 592-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21641641

RESUMEN

Human chorionic gonadotropin (hCG) is one of the earliest signals secreted by the implanting embryo. In addition to its well-known luteotropic function in early pregnancy, hCG also acts directly on decidualizing endometrium. Recently, we demonstrated that recombinant hCG (rhCG) prevented apoptosis in decidualizing human endometrial stromal cells (HESCs) exposed to oxidative stress. Two hCG preparations are widely used clinically: rhCG, produced by recombinant DNA technology, and urinay hCG (uhCG), extracted from urine of post-menopausal women. However, an analysis of the direct effects of rhCG and uhCG on the decidual phenotype of HESCs has not yet been done. In this study, we investigated the effects of uhCG and rhCG on the morphological and functional profiles of decidualizing HESCs. We demonstrate that neither rhCG nor uhCG alter the morphological appearance of the decidual HESC cultures, although rhCG but not uhCG attenuated prolactin expression, a major decidual marker protein. Moreover, rhCG, but not uhCG, protected decidualizing HESCs from oxidative cell death, mediated at least in part by two major mechanisms. First, rhCG, but not uhCG, enhances the expression of manganese superoxide dismutase, a cardinal enzyme in the cellular defense against oxidative damage. Second, rhCG signaling selectively limits activation of the apoptotic machinery in decidualizing HESCs by enhancing Bcl-2 expression whereas uhCG induces the expression of Fas ligand. Our results suggest that rhCG might be a preferable agent to protect the maternal decidua against oxidative damage in pregnancy, especially at the time of implantation and beyond.


Asunto(s)
Gonadotropina Coriónica/farmacología , Gonadotropina Coriónica/orina , Decidua/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Células del Estroma/metabolismo , Adulto , Decidua/citología , Implantación del Embrión/efectos de los fármacos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Prolactina/metabolismo , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Células del Estroma/efectos de los fármacos
5.
Arch Oral Biol ; 47(9): 655-63, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12243969

RESUMEN

Hepatocyte growth factor (HGF), also known as scatter factor, is a broad-spectrum and multifunctional cytokine required for the development, growth and regeneration of various organs and tissues. The expression of HGF in human gingival fibroblasts is induced by inflammatory cytokines such as interleukin 1. Thus, although it is possible that content of HGF in gingival crevicular fluid (GCF) in periodontitis is increased, this has not so far been reported because the volume of GCF is too small to determine HGF by the available enzyme-linked immunosorbent assay (ELISA). A recently developed, highly sensitive ELISA for HGF, with a detection limit of 1 pg/ml sample, has now enabled HGF to be measured in GCF.The mean HGF content in GCF from sites with clinically healthy gingiva, defined by the absence of overt signs of gingival inflammation and a probing depth (PD) <3 mm, was 1.7 ng/ml, and that of periodontitis, defined by obvious alveolar bone loss detected by radiographic examination and a PD> or =3 mm, was 3.23 ng/ml. Although treating the periodontitis did not significantly decrease the HGF concentration despite significantly improved clinical scores such as PD and Gingival Index, the total amount of HGF in GCF did decrease significantly after treatment. HGF was expressed by gingival fibroblasts and inflammatory cells as determined by in situ hybridization. HGF-activator (HGFA), which converts inactive pro-HGF to active mature HGF, was detected in gingival epithelial cells by immunostaining. The expression of HGFA was also confirmed in gingival tissue by reverse transcription-polymerase chain reaction (RT-PCR). These findings indicate that HGF is synthesized and activated in gingiva that is clinically healthy or associated with periodontitis.


Asunto(s)
Líquido del Surco Gingival/química , Factor de Crecimiento de Hepatocito/análisis , Periodontitis/metabolismo , Serina Endopeptidasas/análisis , Adulto , Anciano , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Expresión Génica , Factor de Crecimiento de Hepatocito/genética , Humanos , Hibridación in Situ , Masculino , Persona de Mediana Edad , ARN/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Serina Endopeptidasas/genética
6.
Bone ; 30(1): 191-4, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11792584

RESUMEN

Microstructure of trabecular bone has been examined with a particular emphasis on surface curvatures in two-phase (trabecular and intertrabecular space- i.e., marrow space) structures. Three trabecular bone samples, quantified as "plate-like," "rod-like," and a mixture of these two structural elements according to the structure model index (SMI), were subjected to analysis based on (differential) geometry. A correspondence between the SMI and the mean curvature was found. A method to measure surface curvatures is proposed. The gaussian curvatures averaged over the surfaces for the three analyzed bone structures were all found to be negative, demonstrating their surfaces to be, on average, hyperbolic. In addition, the Euler-Poincaré characteristics and the genus, both characterizing topological features of bone connectivity, were estimated from integral gaussian curvature (Gauss-Bonnet theorem). The three bone microstructures were found to be topologically analogous to spheres with one to three handles.


Asunto(s)
Huesos/anatomía & histología , Huesos/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Persona de Mediana Edad , Modelos Anatómicos , Propiedades de Superficie , Tomografía Computarizada por Rayos X
7.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(1 Pt 1): 010803, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11461216

RESUMEN

Bicontinuous morphologies are ubiquitous in nature and occur at various length scales. Topological features of two such morphologies arising in an ordered block copolymer at equilibrium and a polymer blend during spinodal decomposition are measured from three-dimensional images. Interfacial curvature, coordination number, and interjunction distance distributions exhibit remarkable similarity in these systems, despite vastly different length scales. A channel coordination of 3 is dominant in both morphologies, and topological measurements such as the Euler-Poincaré characteristic and genus are reported.


Asunto(s)
Materiales Biocompatibles/química , Biofisica/métodos , Polímeros/química , Modelos Estadísticos , Probabilidad , Conformación Proteica , Propiedades de Superficie
8.
J Clin Gastroenterol ; 31(3): 230-2, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11034003

RESUMEN

Ninety-six patients treated successively for symptomatic cholelithiasis with extracorporeal shock wave lithotripsy (ESWL) and oral bile acid therapy consisting of ursodeoxycholic acid in daily dosages of 600 mg were prospectively followed for gallstone recurrence for a median of 13 months. Ultrasonography was performed to detect stone recurrence at 3, 6, and 12 months, and then yearly after the termination of therapy. Recurrent stones were found in 17 patients (18%). The cumulative probability of gallstone recurrence was 15.8% at 12 months, 26.1% at 24 months, and 30.7% at 36 months. The probability of stone recurrence over the entire period of observation was not dependent on stone number, whereas the median interval to detection of recurrence was significantly shorter in the patients with multiple stones (2 months) than in those with solitary stones (8 months) (p < 0.05). The rate of impaired gallbladder contractility was higher in patients with recurrence (8/15, 53.3%) when compared with those with no recurrence (15/72, 20.8%) (p < 0.01). Neither age, gender, or stone characteristics predicted stone recurrence. Only one patient with a recurrence reported biliary pain. Of the 15 patients with recurrent stones who opted for further nonsurgical treatment, complete stone disappearance was achieved in 10. Impaired gallbladder function may predict gallstone recurrence after ESWL.


Asunto(s)
Colelitiasis/terapia , Litotricia , Colagogos y Coleréticos/uso terapéutico , Colelitiasis/epidemiología , Femenino , Estudios de Seguimiento , Vaciamiento Vesicular , Humanos , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Prospectivos , Recurrencia , Factores de Tiempo , Ácido Ursodesoxicólico/uso terapéutico
9.
Dig Dis Sci ; 45(7): 1413-21, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10961723

RESUMEN

Phospholipase A2 plays a role in cholesterol gallstone development by hydrolyzing bile phospholipids into lysolecithin and free fatty acids. Lysolecithin and polyunsaturated free fatty acids are known to stimulate the synthesis and/or secretion of gallbladder mucin via a prostanoid pathway, leading to enhancing cholesterol crystal nucleation and growth, and therefore, the action of phospholipase A2 is associated, in part, with bile phospholipid fatty acid. To clarify this hypothesis, we evaluated the effect on bile lipid metastability in vitro of replacing phospholipids with lysolecithin and various free fatty acids. Supersaturated model biles were created with an identical composition (cholesterol saturation index, 1.8; egg yolk lecithin, 34 mM; taurocholate, 120 mM; cholesterol, 25 mM) except for 5%, 10%, or 20% replacement of egg yolk lecithin with a combination of palmitoyl-lysolecithin and a free fatty acid (palmitate, stearate, oleate, linoleate, or arachidonate), followed by time-sequentially monitoring of vesicles and cholesterol crystals using spectrophotometer and video-enhanced differential contrast microscopy. Replacement with hydrophilic fatty acids (linoleate and arachidonate) reduced vesicle formation and promoted cholesterol crystallization, whereas an enhanced cholesterol-holding capacity was evident after replacement with hydrophobic fatty acids (palmitate and stearate). These results indicate that the effect of phospholipase A2 on bile lithogenecity is modulated by the fatty acid species in bile phospholipids, and therefore, that the role of phospholipase A2 in cholesterol gallstone formation is dependent, in part, on biliary phospholipid species selection at the site of hepatic excretion.


Asunto(s)
Bilis/metabolismo , Colelitiasis/etiología , Colesterol/fisiología , Hígado/metabolismo , Fosfolipasas A/fisiología , Fosfolípidos/fisiología , Bilis/química , Colesterol/química , Cristalización , Cristalografía , Huevos/análisis , Lípidos/análisis , Microscopía/métodos , Fosfatidilcolinas/farmacología , Fosfolipasas A2 , Fosfolípidos/clasificación , Proteínas/análisis , Televisión
10.
J Gastroenterol ; 35(6): 450-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10864353

RESUMEN

We recently demonstrated that several organic anions cause dissociation of biliary lipid secretion from that of bile acids; namely, the "uncoupling phenomenon," in association with changes in the phospholipid molecular species in the canalicular membrane lipid bilayer. Because of the uncoupling phenomenon, transcytotic vesicles are retained inside cells, resulting in the accumulation of substances normally excreted in the bile. In the present study, bilirubin ditaurate (BDT; synthetic bilirubin) was used to investigate the effect of bilirubin overload on biliary lipid secretion and the lipid composition of hepatic subcellular fractions, as well as canalicular membrane packing density and fluidity. Male Sprague-Dawley rats underwent cannulation of the bile duct and femoral vein. Sodium taurocholate was infused intravenously at 100 nmol/min per 100 g body weight. Then BDT (50 nmol/min per 100 g body weight) was infused concomitantly, followed by periodic bile collection for analysis of lipids. Bile acid secretion was not significantly affected by the infusion of BDT. In contrast, the secretion of cholesterol and phospholipids was decreased by 56.7% and 49.2%, respectively, compared with control. The phosphatidylcholine hydrophobicity of canalicular membrane vesicles, estimated by the molar ratio of saturated to unsaturated fatty acids (S/U ratio) was decreased, but not significantly by BDT infusion. With BDT infusions, the biliary cholesterol/phospholipid (C/P) ratio was increased by 19%; canalicular membrane vesicle fluidity was decreased by 5.8%, whereas P-glycoprotein expression was unchanged. As P-glycoprotein expression was not altered, our findings suggested that the reduced canalicular membrane vesicle fluidity was a crucial regulator of canalicular membrane transporter function.


Asunto(s)
Canalículos Biliares/metabolismo , Bilirrubina/análogos & derivados , Bilirrubina/farmacología , Metabolismo de los Lípidos , Fluidez de la Membrana/fisiología , Taurina/análogos & derivados , Animales , Bilis , Ácidos y Sales Biliares/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Taurina/farmacología
11.
J Bone Joint Surg Br ; 82(3): 392-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10813176

RESUMEN

We performed superselective angiography in 28 hips in 25 patients with Perthes' disease in order to study the blood supply of the lateral epiphyseal arteries (LEAs). Interruption of the LEAs at their origin was observed in 19 hips (68%). Revascularisation in the form of numerous small arteries was seen in ten out of 11 hips in the initial stage of Perthes' disease, in seven of eight in the fragmentation stage and in five of nine in the healing stage. Penetration of mature arteries into the depths of the epiphysis was seen in four of nine hips in the healing stage. Vascular penetration was absent in the weight-bearing portion of the femoral head below the acetabular roof. Interruption of the posterior column artery was seen where it passed through the capsule in seven hips when they lay either in internal rotation or in abduction with internal rotation. We suggest that in Perthes' disease the blood supply of the LEAs is impaired at their origin and that revascularisation occurs from this site by ingrowth of small vessels into the femoral epiphysis. This process may be the result of recurrent ischaemic episodes.


Asunto(s)
Angiografía , Epífisis/irrigación sanguínea , Enfermedad de Legg-Calve-Perthes/diagnóstico por imagen , Adolescente , Niño , Preescolar , Circulación Colateral/fisiología , Femenino , Humanos , Isquemia/diagnóstico por imagen , Masculino , Neovascularización Fisiológica/fisiología , Recurrencia , Soporte de Peso/fisiología
12.
Arch Orthop Trauma Surg ; 119(7-8): 388-93, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10613226

RESUMEN

Posterior rotational osteotomy in 46 hips of 39 patients with femoral head osteonecrosis was reviewed radiographically and clinically after 2-12 years of follow-up (mean 5 years). The age of the patients at the time of surgery ranged from 18 to 60 years, with a mean of 35 years. There were 18 women and 21 men. The cause of the osteonecrosis was steroid administration in 14, alcohol abuse in 5, trauma in 16, and no apparent risk factor in 4. According to the Ficat staging system, 2 hips were stage II, 30 hips III, and 14 hips stage IV. All hips had an extensive lesion. Forty-one hips showed less than 1/3 noncollapsed posterior living area, which was a contraindication for traditional anterior rotational osteotomy. The posterior rotational angle was 60-180 deg with an mean of 127 deg. Recollapse of the final follow-up anteroposterior radiograph was prevented in 36 hips (78%). Progressive joint space narrowing was found in 12 hips (26%). Of these hips, 9 suffered recollapse, while the remaining 3 hips did not. Clinically, 32 hips (70%) showed excellent or good results (both hips in stage II, 23 of 30 hips in stage III, 7 of 14 hips in stage IV. A fair or poor result was seen in 14 hips (30%)). These results suggest that posterior rotational osteotomy is effective in delaying the progression of degeneration for large necrotic lesions, especially in young patients. Extent of rotation is limited to 150 deg because of limitations of bone quality. The indications should be refined further, and longer term follow-up is necessary.


Asunto(s)
Necrosis de la Cabeza Femoral/cirugía , Osteotomía/métodos , Adolescente , Adulto , Femenino , Necrosis de la Cabeza Femoral/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Resultado del Tratamiento
13.
Mol Genet Metab ; 68(3): 346-56, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10562461

RESUMEN

The expression of carbamoyl phosphate synthetase I (CPS) gene is suppressed in the liver of carnitine-deficient juvenile visceral steatosis (JVS) mice at weaning and under starvation at adult age. To clarify the suppression mechanism, we produced CPSL transgenic JVS mice carrying a transgene composed of the chloramphenicol acetyltransferase (CAT) gene with the upstream region (-12 kb to +138) of the rat CPS gene and CPSE transgenic JVS mice carrying a transgene composed of the luciferase gene with minimal promoter (299 bp from -161 to +138) and enhancer (469 bp around -6.3 kb) fragments of the rat gene. The expression of the CAT gene as well as the endogenous CPS was suppressed in CPSL transgenic JVS mice, but luciferase gene expression was not suppressed in CPSE transgenic JVS mice. We isolated the 5'-upstream region of the mouse CPS gene and identified an activator protein-1 (AP-1) site downstream of the minimum enhancer region of both rat and mouse CPS genes. In conjunction with the 313-bp mouse promoter region, the 714-bp mouse enhancer fragment conferred a cell-type-dependent hormone responsiveness. In rat primary cultured hepatocytes, the addition of oleic acid suppressed reporter gene expression induced by dexamethasone in the construct containing the enhancer fragment of 714 bp with the AP-1 site, but not in its AP-1 site mutants or in 519 bp without the AP-1 site. These results strongly suggest that direct protein-protein interaction between AP-1 and glucocorticoid receptor is not involved in the suppression of the CPS gene in JVS mice and that the AP-1 element is the cis-element which is responsible for the suppression.


Asunto(s)
Carbamoil-Fosfato Sintasa (Amoniaco)/genética , Carnitina/deficiencia , Regulación Enzimológica de la Expresión Génica , Hígado/enzimología , Animales , Sitios de Unión , Carbamoil-Fosfato Sintasa (Amoniaco)/biosíntesis , Cloranfenicol O-Acetiltransferasa/genética , Clonación Molecular , Modelos Animales de Enfermedad , Elementos de Facilitación Genéticos , Represión Enzimática , Genes Reporteros , Neoplasias Hepáticas Experimentales , Luciferasas/genética , Ratones , Ratones Transgénicos , Regiones Promotoras Genéticas , Ratas , Mapeo Restrictivo , Factor de Transcripción AP-1/metabolismo , Células Tumorales Cultivadas
14.
Biosci Biotechnol Biochem ; 63(8): 1383-91, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10500999

RESUMEN

Rat fetuin, which is the rat counterpart of human alpha 2-HS glycoprotein and bovine fetuin, is only detectable in calcified tissues such as bone matrices and dentin, and bone cells such as osteoblasts and osteocytes immunohistochemically. The effect of this protein on bone resorption was examined to study its physiological role in bone metabolism. Rat fetuin increased bone resorption in the presence of low concentrations of parathyroid hormone (PTH), but it had no activity on bone resorption without PTH. The increase in bone resorption by PTH and PTH plus rat fetuin was inhibited by the addition of chymostatin, an inhibitor for cathepsin L. Moreover, we found that when type I collagen from rat was preincubated with rat fetuin, the digestion of rat type I collagen by cathepsin L was increased. These findings suggest that rat fetuin present in bone matrix is important in bone resorption.


Asunto(s)
Resorción Ósea/inducido químicamente , Endopeptidasas , Hormona Paratiroidea/farmacología , alfa-Fetoproteínas/farmacología , Animales , Resorción Ósea/fisiopatología , Catepsina L , Catepsinas/metabolismo , Colágeno/metabolismo , Medios de Cultivo Condicionados , Cisteína Endopeptidasas , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Ratones , Ratones Endogámicos ICR , Fosforilación , Embarazo , Estimulación Química , alfa-Fetoproteínas/fisiología
15.
J Gastroenterol Hepatol ; 14(6): 578-82, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10385068

RESUMEN

BACKGROUND: Several organic anions cause dissociation of biliary lipid secretion from bile acid secretion (uncoupling). As bile lipids originate from liver microsomes and are transported by carrier proteins and/or transcytotic vesicles, such a reduction of biliary lipid secretion may lead to cytosolic accumulation of vesicles. This study investigated whether bilirubin conjugate, a physiologically important organic anion, caused uncoupling and whether hepatic retention of compounds carried by transcytotic vesicles occurred subsequently, using bilirubin ditaurate, a synthetic commercially available compound. METHODS: Cannulation of the bile duct and femoral vein was done in male Sprague-Dawley rats. Sodium taurocholate was infused intravenously at a constant rate of 100 nmol/min per 100 g bodyweight. Bilirubin ditaurate (50 nmol/min per 100 g bodyweight) was infused concomitantly, followed by periodical bile collection for analysis of lipids, total protein and immunoglobulin A. RESULTS: Biliary bile acid secretion was not changed significantly by infusion of bilirubin ditaurate. In contrast, the secretion of cholesterol, phospholipids and immunoglobulin A was decreased by 57.3, 48.7 and 44.8%, respectively. The biliary cholesterol:phospholipid ratio was increased by 19%. Uncoupling was caused by bilirubin ditaurate and biliary immunoglobulin A secretion was decreased. CONCLUSIONS: As immunoglobulin A is a major protein carried by intrahepatic transcytotic vesicles, uncoupling may involve impairment of intrahepatic vesicular transport. Also, a reduction of immunoglobulin A secretion into bile by organic anion-induced uncoupling may weaken biliary immunity.


Asunto(s)
Sistema Biliar/efectos de los fármacos , Sistema Biliar/metabolismo , Bilirrubina/análogos & derivados , Metabolismo de los Lípidos , Proteínas/metabolismo , Taurina/análogos & derivados , Animales , Ácidos y Sales Biliares/metabolismo , Bilirrubina/química , Bilirrubina/farmacología , Cromatografía Líquida de Alta Presión , Masculino , Ratas , Ratas Sprague-Dawley , Taurina/química , Taurina/farmacología
16.
J Biol Chem ; 274(19): 13541-6, 1999 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-10224123

RESUMEN

In this study, we show that N-acetylcysteine (NAC), a precursor of glutathione and an intracellular free radical scavenger, almost completely prevented hepatocyte growth factor (HGF)-suppressed growth of Sarcoma 180 and Meth A cells, and HGF-induced apoptosis, assessed by DNA fragmentation, and increase in caspase-3 activity, in Sarcoma 180 cells. The reduced form of glutathione also prevented HGF-suppressed growth of the cells as effective as NAC. Ascorbic acid partially prevented the effect of HGF, but other antioxidants such as superoxide dismutase, catalase, and vitamin E, and the free radical spin traps N-t-butyl-alpha-phenylnitrone and 3,3,5, 5-tetramethyl-1-pyrroline-1-oxide did not have protective effects. HGF caused morphological changes of the cells, many cells showing condensation and rounding, and enhanced the generation of intracellular reactive oxygen species (ROS) as judged by flow cytometric analysis using 2',7'-dichlorofluorescein diacetate. NAC completely prevented both HGF-induced morphological changes and the enhancement of ROS generation in the cells. However, NAC did not prevent the HGF-induced scattering of Madin-Darby canine kidney cells. To our knowledge, this is the first report that HGF stimulates the production of ROS, and our results suggest the involvement of oxidative stress in the mechanism by which HGF induces growth suppression of tumor cells.


Asunto(s)
División Celular/fisiología , Factor de Crecimiento de Hepatocito/fisiología , Sarcoma Experimental/patología , Acetilcisteína/farmacología , Animales , Antioxidantes/farmacología , Apoptosis , Línea Celular , Perros , Estrés Oxidativo , Especies Reactivas de Oxígeno , Células Tumorales Cultivadas
17.
Arch Oral Biol ; 44(2): 135-47, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10206332

RESUMEN

Hepatocyte growth factor/scatter factor (HGF/SF), a broad-spectrum and multifunctional cytokine, is essential for the development of tissues including tooth. Here it was found that the HGF/SF content of human dental papillae obtained from 8 to 16-year-old individuals decreased significantly with age. Cultured fibroblasts prepared from the dental papillae of individuals of different ages produced HGF/SF at almost the same rate, but the sensitivities of the cells to interleukin-1alpha and tumour necrosis factor-alpha for the production of HGF/SF increased with age. Generally, mesenchymal cells such as fibroblasts produce HGF/SF but do not express c-Met, a receptor for HGF/SF, yet fibroblasts in dental papilla and cultured fibroblasts prepared from dental papilla did express c-Met, as determined by immunohistochemistry, in situ hybridization and reverse transcription-polymerase chain reaction. Recombinant human [125I]iodo-HGF/SF specifically bound to cell-surface macromolecules with a mol. wt of 146,000, which is the same as that of the beta-subunit of c-Met. The physiological role of c-Met on fibroblasts in dental papilla is unknown, but the addition of 2 ng of HGF/SF per ml to the culture medium significantly stimulated DNA synthesis in the cells, as determined by pulse labelling with [3H]thymidine. Exogenous HGF/SF also stimulated secretion by the cells of vascular endothelial growth factor, a cytokine that induces blood vessel-formation. These results suggest that HGF/SF may be involved in tooth development via autocrine mechanisms.


Asunto(s)
Papila Dental/metabolismo , Fibroblastos/metabolismo , Factor de Crecimiento de Hepatocito/análisis , Proteínas Proto-Oncogénicas c-met/análisis , Adolescente , Envejecimiento/genética , Envejecimiento/metabolismo , Comunicación Autocrina/fisiología , Células Cultivadas , Niño , ADN/biosíntesis , Papila Dental/citología , Factores de Crecimiento Endotelial/biosíntesis , Fibroblastos/citología , Regulación de la Expresión Génica , Factor de Crecimiento de Hepatocito/genética , Humanos , Inmunohistoquímica , Hibridación in Situ , Interleucina-1/farmacología , Radioisótopos de Yodo , Linfocinas/biosíntesis , Mesodermo/citología , Mesodermo/metabolismo , Peso Molecular , Neovascularización Fisiológica , Odontogénesis/fisiología , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-met/genética , Radiofármacos , Timidina/metabolismo , Tritio , Factor de Necrosis Tumoral alfa/farmacología , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
18.
J Clin Gastroenterol ; 26(4): 287-91, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9649013

RESUMEN

Inhibitors of 3-hydroxy,3-methylglutaryl coenzyme A (HMG-CoA) reductase have been reported to decrease the cholesterol saturation index (CSI) in duodenal bile in humans and to prevent formation of cholesterol gallstones in animal studies. We performed a prospective study to evaluate the role of HMG-CoA reductase inhibitors as gallstone-dissolving agents. Fifty patients with radiolucent gallstones in a gallbladder opacifying at drip infusion cholecystography were treated with either 10 mg/day simvastatin plus 600 mg/day ursodeoxycholic acid (group 1, n=26) or 600 mg/day ursodeoxycholic acid alone (group 2, n=24) for 12 months. The ratio of solitary to multiple gallstone cases was 21:29. Plasma lipid levels were assessed and ultrasonographic examination of the gallbladder was performed at baseline and at 3-month intervals during treatment. Duodenal bile sampling was performed in five patients in each group at baseline and after 12 months of treatment. Plasma cholesterol decreased significantly in group 1 but not in group 2. In solitary gallstone cases, no significant difference in dissolution rates was observed between groups 1 (3 of 9, 33%) and 2 (4 of 12, 33%). In contrast, the dissolution rate in multiple gallstone cases was significantly higher in group 1 (12 of 17, 71%) than in group 2 (3 of 12, 25%) (p < 0.01). Bile cholesterol saturation index was significantly decreased (p < 0.01) but did not significantly differ between the two groups. These results suggest that combination therapy with simvastatin and ursodeoxycholic acid is more effective for cholesterol gallstone dissolution than ursodeoxycholic acid monotherapy in patients with multiple gallstones.


Asunto(s)
Colelitiasis/tratamiento farmacológico , Colesterol/análisis , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Simvastatina/uso terapéutico , Ácido Ursodesoxicólico/uso terapéutico , Bilis/química , Colelitiasis/química , Colesterol/sangre , Quimioterapia Combinada , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Metabolismo de los Lípidos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Simvastatina/administración & dosificación , Ácido Ursodesoxicólico/administración & dosificación
19.
Clin Ther ; 20(3): 477-85, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9663363

RESUMEN

The use of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors has become common in the treatment of hypercholesterolemia. The present uncontrolled study was undertaken to determine the effect of cerivastatin sodium (BAY w 6228), a new HMG-CoA reductase inhibitor, on biliary lipid levels in patients with hypercholesterolemia. Twenty-one hypercholesterolemic patients (World Health Organization type IIa = 16 patients; type IIb = 5 patients) received placebo during a 4- to 6-week observation period, after which they received cerivastatin sodium 0.2 mg/d for 12 weeks. Fasting blood samples were drawn for the measurement of serum lipid levels early in the morning before the start of treatment and once a month for each of the 12 weeks of cerivastatin sodium treatment. Gallbladder bile samples were aspirated with a duodenal tube by cerulein stimulation to assess bile lithogenicity. Serum total cholesterol levels decreased markedly after 12 weeks. However, no significant difference was found in the molar percentage composition of biliary lipids (e.g., cholesterol, phospholipids, and total bile acids) or in individual biliary bile acids. Consequently, no significant change in bile cholesterol saturation index was found. The index values before and after 12 weeks of treatment were 0.81 +/- 0.38 and 0.80 +/- 0.47, respectively, whereas when patients were grouped by type of hypercholesterolemia, there was a tendency toward decreased lithogenicity in patients with type IIb but not type IIa hypercholesterolemia. We concluded that cerivastatin sodium was an effective cholesterol-lowering drug that did not appear to worsen biliary lipid metabolism and that may decrease lithogenicity in patients with type IIb hypercholesterolemia.


Asunto(s)
Bilis/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Hipolipemiantes/uso terapéutico , Metabolismo de los Lípidos , Piridinas/uso terapéutico , Adulto , Anciano , Bilis/efectos de los fármacos , Ácidos y Sales Biliares/metabolismo , Colesterol/sangre , Dieta , Ácidos Grasos/metabolismo , Femenino , Humanos , Hipercolesterolemia/metabolismo , Lípidos/sangre , Masculino , Persona de Mediana Edad , Fosfatidilcolinas/metabolismo , Triglicéridos/sangre
20.
J Biochem ; 124(1): 179-86, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9644261

RESUMEN

Rat fetuin, a counterpart of human alpha2-HS glycoprotein and bovine fetuin, shows strong intermolecular binding and association with other serum proteins. Therefore, to measure its concentration in rat serum, we pretreated serum samples with 1% SDS plus 5% (ca. 0.7 M) 2-mercaptoethanol at 100 degrees C for 3 min, and then subjected them to SDS-PAGE under reducing conditions followed by Western blotting. We found that the fetuin concentrations in normal rat serum determined by Western blotting were 2.5-4.5 mg/ml. These concentrations were three orders of magnitude higher than the previously reported concentrations. We also tried to measure the fetuin concentration in rat serum by means of an enzyme-linked immunosorbent assay after treatment of the samples with 0.1% sodium dodecyl sulfate (SDS) plus 10 mM 2-mercaptoethylamine at 100 degrees C for 3 min, but it gave a value of about 1/4 of that on Western blotting. Rat fetuin is expressed mainly in the liver, with a peak 2-4 weeks after birth, as determined by Northern blot analysis. The fetuin mRNA level in the liver changes almost in parallel with its serum concentration. The tibia also expresses fetuin, but much less than the liver.


Asunto(s)
Envejecimiento/sangre , ARN Mensajero/genética , alfa-Fetoproteínas/metabolismo , Animales , Northern Blotting , Western Blotting , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Ratas , alfa-Fetoproteínas/genética
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