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1.
Dis Esophagus ; 30(6): 1-8, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-28475746

RESUMEN

Jejunostomy, which requires the fixation of the jejunum to the abdominal wall, is commonly used as an enteral feeding access after esophagectomy. However, this procedure sometimes causes severe complications, such as mechanical bowel obstruction. In 2009, we developed a modified approach to insert an enteral feeding tube through the reconstructed gastric tube using the round ligament of the liver. The aim of this study is to investigate the usefulness of this approach as compared to the approach through jejunostomy. Between January 2005 and March 2015, 420 patients with thoracic esophageal cancer underwent esophagectomy via thoracotomy and laparotomy. Of these, 214 underwent feeding jejunostomy (FJ group) and 206 patients underwent feeding via gastric tube with round ligament of the liver (FG group). Catheter-related complications, other postoperative complications, and mortality were compared between the two groups. The incidence of catheter site infection during catheterization in the FG group was significantly lower (n = 1/206, 0.5%) compared to the FJ group (n = 11/214, 5.1%) (P < 0.01). The postoperative bowel obstruction did not occur in the FG group, while it occurred in eight patients (3.7%) in the FJ group (P < 0.01). The incidences of other catheter-related and postoperative complications were similar between the two groups. Feeding catheter gastrostomy with the round ligament of the liver can be a useful enteral feeding access after esophagectomy, because the incidence rate of severe catheter-related complications, such as surgical site infection and mechanical obstruction tend to be lower with this technique compare to jejunostomy.


Asunto(s)
Nutrición Enteral/métodos , Gastrostomía/métodos , Obstrucción Intestinal/prevención & control , Complicaciones Posoperatorias/prevención & control , Ligamento Redondo del Hígado/cirugía , Anciano , Nutrición Enteral/efectos adversos , Neoplasias Esofágicas/cirugía , Esofagectomía/efectos adversos , Esofagectomía/métodos , Femenino , Humanos , Incidencia , Obstrucción Intestinal/epidemiología , Obstrucción Intestinal/etiología , Yeyunostomía/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
2.
Oral Dis ; 21(1): 97-105, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24330147

RESUMEN

OBJECTIVE: We previously reported that matrix metalloproteinase-3(MMP-3) accelerates wound healing following dental pulp injury. In this study, we tested the hypothesis that induction of MMP-3 activity by interleukin-1ß would promote proliferation and apoptosis of dental pulp cells. MATERIALS AND METHODS: Dental pulp cells were isolated from rat incisors and subjected to interleukin-1ß. Matrix metalloproteinase-3 mRNA and protein expression were assessed using reverse transcription-polymerase chain reaction and Western blotting, respectively. Matrix metalloproteinase-3 activity was measured using fluorescence. Dental pulp cell proliferation and apoptosis were determined using enzyme-linked immunosorbent assays (ELISA) for BrdU and DNA fragmentation, respectively. siRNA was used to reduce MMP-3 transcripts in these cells. RESULTS: Treatment with interleukin-1ß increased MMP-3 mRNA and protein levels as well as its activity in dental pulp cells. Cell proliferation was also markedly increased, with no changes in apoptosis observed. Treatment with siRNA against MMP-3 potently suppressed this interleukin-1ß-induced increase in MMP-3 expression and activity, and also suppressed cell proliferation but unexpectedly increased apoptosis in these cells (P < 0.05). This siRNA-mediated increase in apoptosis could be reversed with exogenous MMP-3 stimulation (P < 0.05). CONCLUSIONS: Interleukin-1ß induces MMP-3-regulated cell proliferation and suppresses apoptosis in dental pulp cells.


Asunto(s)
Proliferación Celular/fisiología , Pulpa Dental/fisiología , Interleucina-1beta/farmacología , Metaloproteinasa 3 de la Matriz/fisiología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Western Blotting , Proliferación Celular/efectos de los fármacos , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
3.
Oral Dis ; 20(4): 395-403, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23731055

RESUMEN

OBJECTIVES: We examined whether mouse embryonic stem (ES) cells can differentiate into odontoblast-like cells without epithelial-mesenchymal interaction. MATERIALS AND METHODS: Cells were cultured by the 'hanging drop' method using a collagen type-I scaffold (CS) combined with bone morphogenetic protein (BMP)-4 (CS/BMP-4). Expression of odontoblast-related mRNA and protein, and cell proliferation were performed by reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence staining and WST-1 assay, respectively. RESULTS: Cells potently expressed odontoblast-related cell marker mRNAs following induction of odontoblastic differentiation. Dentin sialophosphoprotein, a marker of mature odontoblasts, was strongly expressed in differentiated ES cells. The cells also acquired an odontoblast-like functional phenotype, as evidenced by the appearance of alkaline phosphatase activity and calcification. The cell-surface expression of α2, α6, αV and αVß3 integrin proteins was rapidly upregulated in differentiated cells. Finally, anti-α2 integrin antibody suppressed the expression of odontoblastic markers in cells grown using this culture system, suggesting that α2 integrin expression in ES cells triggers their differentiation into odontoblast-like cells. CONCLUSIONS: Mouse ES cells cultured by the 'hanging drop' method are able to differentiate into cells with odontoblast-specific physiological functions and cell-surface integrin protein expression.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/citología , Odontoblastos/citología , Animales , Células Cultivadas , Técnicas Citológicas/métodos , Ratones
4.
Oral Dis ; 20(5): 505-13, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23902456

RESUMEN

OBJECTIVES: Matrix metalloproteinase (MMP)-3 expression increases after pulpectomy and accelerates angiogenesis in rat dental pulp by an uncharacterised mechanism. Odontoblasts, a major component of dental pulp, could represent a therapeutic target. We investigated whether MMP-3 activity is induced by cytokines and/or is associated with cell proliferation and apoptosis in embryonic stem cell-derived odontoblast-like cells. MATERIALS AND METHODS: We used reverse transcriptase polymerase chain reaction, western blotting, an MMP-3 activity assay, a BrdU-cell proliferation enzyme-linked immunosorbent assay and DNA fragmentation analysis to evaluate siRNA-mediated downregulation of MMP-3 expression and activity, and any changes in the proliferative and apoptotic responses associated with this reduced expression. RESULTS: Pro-inflammatory cytokines (interleukin-1ß, tumour necrosis factor-α and interferon-γ, at relatively low concentrations) induced MMP-3 mRNA and protein expression, and increased MMP-3 activity and cell proliferation, but not apoptosis. MMP-3 silencing produced a potent and significant suppression of cytokine-induced MMP-3 expression and activity, decreased cell proliferation and increased apoptosis. These effects were rescued by application of exogenous MMP-3. CONCLUSIONS: Our results suggest that pro-inflammatory cytokines induce MMP-3-regulated cell proliferation and anti-apoptosis effects in odontoblast-like cells derived from embryonic stem cells, in addition to their well-documented destructive role in inflammation.


Asunto(s)
Proliferación Celular , Citocinas/fisiología , Células Madre Embrionarias/citología , Metaloproteinasa 3 de la Matriz/fisiología , Odontoblastos/citología , Animales , Apoptosis/fisiología , Western Blotting , División Celular/fisiología , Línea Celular , Ratones , Odontoblastos/efectos de los fármacos , Proteínas
5.
Br J Biomed Sci ; 68(1): 29-33, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21473259

RESUMEN

Among five components of metabolic syndrome, high-density lipoprotein (HDL) cholesterol is unique because it is not significantly associated with blood pressure. This study looks at cross-sectional relationships between HDL cholesterol and hypertension using medical check-up data from 1803 apparently healthy Japanese men aged 49.9 +/- 9.0 years, and 1150 Japanese women aged 49.5 +/- 9.0 years. Pearson's correlation coefficients between systolic blood pressure (SBP)/diastolic blood pressure (DBP) and HDL cholesterol were -0.01 (ns)/-0.01 (ns) in men and -0.04 (ns)/-0.01 (ns) in women. The standardised partial regression coefficient of HDL cholesterol for SBP/DBP (mmHg) controlling for age, body mass index (BMI), fasting plasma glucose (FPG), triglycerides, high-sensitivity C-reactive protein (hs-CRP) and low-density lipoprotein (LDL) cholesterol were 0.15 (P < 0.0001)/0.15 (P < 0.0001) in men and 0.10 (P < 0.0001)/0.12 (P < 0.0001) in women. The odds ratio (OR; 95% confidence interval [CI]) of a 1 mg/dL increment of HDL cholesterol for hypertension controlling for age, BMI, FPG, triglycerides, hs-CRP, LDL cholesterol, metabolic syndrome, diabetes, exercise status, drinking status, and smoking status was 1.03 (1.02-1.04; P < 0.001) in men and 1.03 (1.01-1.05; P = 0.002) in women. Thus, HDL cholesterol was independently positively associated with hypertension in apparently healthy Japanese men and women.


Asunto(s)
HDL-Colesterol/sangre , Hipertensión/etiología , Síndrome Metabólico/sangre , Adulto , Pueblo Asiatico , Presión Sanguínea/fisiología , Índice de Masa Corporal , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo
6.
Xenobiotica ; 39(11): 795-802, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19845430

RESUMEN

Cytochromes P450 (P450) involved in letrozole metabolism were investigated. Among 13 recombinant P450 forms examined, only P450 2A6 and 3A4 showed activities in transforming letrozole to its carbinol metabolite with small K(m) and high Vmax values yielding apparent Vmax/K(m) values of 0.48 and 0.24 nl min(-1) nmol(-1) P450, respectively. The metabolic activities of individual human liver microsomes showed a significant correlation with coumarin 7-hydroxylase activities (P450 2A6 marker) at a letrozole concentration of 0.5 microM, while a good correlation was also seen with testosterone 6beta-hydroxylase activities (P450 3A4 marker) at 5 microM substrate concentration with different inhibition by 8-methoxypsolaren. Significantly low carbinol-forming activities were seen in human liver microsomes from individuals possessing CYP2A6*4/*4 (whole CYP2A6 gene deletion) at a letrozole concentration of 0.5 microM. A Vmax/K(m) value measured for CYP2A6.7 (amino acid substitution type) in human liver microsomes, in the presence of anti-P450 3A4 antibodies, was approximately seven-fold smaller than that for CYP2A6.1 (wild-type). These results demonstrate that P450 2A6 and 3A4 catalyse the conversion of letrozole to its carbinol metabolite in vitro at low and high concentrations of letrozole. Polymorphic variation of CYP2A6 is considered to be relevant to inter-subject variation in therapeutic exposure of letrozole.


Asunto(s)
Antineoplásicos/farmacocinética , Hidrocarburo de Aril Hidroxilasas/metabolismo , Microsomas Hepáticos/enzimología , Nitrilos/farmacocinética , Triazoles/farmacocinética , Antineoplásicos/química , Hidrocarburo de Aril Hidroxilasas/genética , Reactivos de Enlaces Cruzados/farmacología , Citocromo P-450 CYP2A6 , Citocromo P-450 CYP3A/metabolismo , Inhibidores del Citocromo P-450 CYP3A , Inhibidores Enzimáticos/farmacología , Genotipo , Humanos , Cetoconazol/farmacología , Letrozol , Metoxaleno/farmacología , Microsomas Hepáticos/efectos de los fármacos , Nitrilos/química , Oxidorreductasas/metabolismo , Esteroide Hidroxilasas/metabolismo , Triazoles/química
7.
Int J Clin Pharmacol Ther ; 45(2): 98-109, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17323789

RESUMEN

OBJECTIVE: The authors compared the pharmacokinetics and pharmacological effects of the immunomodulator fingolimod in healthy white and Asian subjects for potential ethnic differences. METHODS: White and Asian (Japanese) healthy subjects were demographically matched for sex, age and weight. Subjects received single 1.25 mg doses of fingolimod (6 ethnic pairs), 2.5 mg (7 pairs), 5 mg (6 pairs) or 5 mg/day for 7 days (6 pairs). The pharmacokinetics of fingolimod, major metabolites, peripheral blood lymphocyte counts and heart rate were characterized over 1 month after single-dose and 2 months after multiple-dose administration. RESULTS: There were no clinically relevant differences in the fingolimod dose Cmax or dose AUC relationships between Asian subjects (slopes 0.84 and 1.05) versus white subjects (slopes 1.13 and 1.26) after single-dose administration. During multiple-dose administration, there were no clinically relevant interethnic differences in fingolimod accumulation ratios (6.6 +/- 0.4 for whites, 7.0 +/- 0.7 for Asians), area under the concentration-time curve (390 +/- 73 versus 382 +/- 106 ng x h/ml), or elimination half-life (7.4 +/- 0.8 versus 7.9 +/- 2.0 days). The acute decrease in lymphocyte counts after single- and multiple-dose fingolimod were similar in the two ethnic groups. The lymphocyte recovery rate to baseline after a 5 mg single dose and 5 mg/day multiple dose was reduced by 36 and 15% in Asian subjects compared with white subjects. The transient, acute decrease in heart rate after the first dose of fingolimod and the subsequent return to baseline was similar in the two ethnic groups. CONCLUSION: There were no marked differences between healthy white and Asian subjects in fingolimod single-dose and multiple-dose pharmacokinetics, lymphocyte trafficking and heart rate responses.


Asunto(s)
Pueblo Asiatico , Inmunosupresores/farmacocinética , Glicoles de Propileno/farmacocinética , Esfingosina/análogos & derivados , Población Blanca , Área Bajo la Curva , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Clorhidrato de Fingolimod , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/sangre , Inmunosupresores/orina , Inactivación Metabólica/etnología , Recuento de Linfocitos , Linfocitos/citología , Linfocitos/efectos de los fármacos , Masculino , Tasa de Depuración Metabólica , Glicoles de Propileno/efectos adversos , Glicoles de Propileno/sangre , Glicoles de Propileno/orina , Esfingosina/efectos adversos , Esfingosina/sangre , Esfingosina/farmacocinética , Esfingosina/orina
8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(4 Pt 1): 041132, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17994961

RESUMEN

We investigate both continuous (second-order) and discontinuous (first-order) transitions to macroscopic synchronization within a single class of discrete, stochastic (globally) phase-coupled oscillators. We provide analytical and numerical evidence that the continuity of the transition depends on the coupling coefficients and, in some nonuniform populations, on the degree of quenched disorder. Hence, in a relatively simple setting this class of models exhibits the qualitative behaviors characteristic of a variety of considerably more complicated models. In addition, we study the microscopic basis of synchronization above threshold and detail the counterintuitive subtleties relating measurements of time-averaged frequencies and mean-field oscillations. Most notably, we observe a state of suprathreshold partial synchronization in which time-averaged frequency measurements from individual oscillators do not correspond to the frequency of macroscopic oscillations observed in the population.

9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(4 Pt 1): 041107, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17500865

RESUMEN

We study synchronization in populations of phase-coupled stochastic three-state oscillators characterized by a distribution of transition rates. We present results on an exactly solvable dimer as well as a systematic characterization of globally connected arrays of N types of oscillators (N=2,3,4) by exploring the linear stability of the nonsynchronous fixed point. We also provide results for globally coupled arrays where the transition rate of each unit is drawn from a uniform distribution of finite width. Even in the presence of transition rate disorder, numerical and analytical results point to a single phase transition to macroscopic synchrony at a critical value of the coupling strength. Numerical simulations make possible further characterization of the synchronized arrays.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(6 Pt 1): 061116, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17677229

RESUMEN

We derive an exact expression for entropy production during effusion of an ideal gas driven by momentum transfer in addition to energy and particle flux. Following the treatment in Cleuren [Phys. Rev. E 74, 021117 (2006)], we construct a master equation formulation of the process and explicitly verify the thermodynamic fluctuation theorem, thereby directly exhibiting its extended applicability to particle flows and hence to hydrodynamic systems.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(2 Pt 1): 021117, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17025403

RESUMEN

The probability distribution of the entropy production for the effusion of an ideal gas between two compartments is calculated explicitly. The fluctuation theorem is verified. The analytic results are in good agreement with numerical data from hard disk molecular dynamics simulations.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 74(3 Pt 1): 031113, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17025600

RESUMEN

Synchronization of stochastic phase-coupled oscillators is known to occur but difficult to characterize because sufficiently complete analytic work is not yet within our reach, and thorough numerical description usually defies all resources. We present a discrete model that is sufficiently simple to be characterized in meaningful detail. In the mean-field limit, the model exhibits a supercritical Hopf bifurcation and global oscillatory behavior as coupling crosses a critical value. When coupling between units is strictly local, the model undergoes a continuous phase transition that we characterize numerically using finite-size scaling analysis. In particular, we explicitly rule out multistability and show that the onset of global synchrony is marked by signatures of the XY universality class. Our numerical results cover dimensions d=2, 3, 4, and 5 and lead to the appropriate XY classical exponents beta and nu, a lower critical dimension dlc=2, and an upper critical dimension duc=4.

13.
J Cereb Blood Flow Metab ; 11(4): 529-44, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1646826

RESUMEN

Brain distribution of the opiate receptor antagonist, cyclofoxy (CF), was evaluated at equilibrium in rats. A combination of i.v. injection and constant i.v. infusion was used to administer CF over a wide dose range (2.4-450 nmol/rat). Kinetic simulations and experimental results showed that this administration schedule accomplishes "true" tissue-blood equilibrium of CF within 60 min. To estimate the receptor-ligand binding parameters, we assumed that the CF concentration at the receptor site is identical to that in plasma water at equilibrium, and can be calculated from measured blood data after corrections for radiolabeled metabolites and plasma protein binding. This assumption was supported by CSF and plasma water measurements at equilibrium. Regional KD, Bmax, and a nonspecific tissue binding equilibrium constant (Keq) were estimated by fitting the tissue and plasma water concentrations to a single receptor model; the estimated values were 1.4-2.9 nM, 15-74 pmol/g of tissue, and 5.2-8.0, respectively. They are in good agreement with previous in vitro measurements (Rothman and McLean, 1988) as well as in vivo estimates from i.v. injection experiments (Sawada et al., 1990c). The conventional method to estimate the receptor-ligand binding parameters using data from cerebellum to approximate nonspecific tissue binding was found to be unacceptable. Although cerebellum is a brain region with no opiate receptors in rats, small differences in nonspecific tissue binding in different brain regions resulted in significant overestimations of KD and Bmax with this method. Receptor-active and -inactive enantiomers [[18F](-)-CF and [3H](+)-CF)] were simultaneously administered to the same animal and the receptor-bound CF concentration could be accurately measured; this method was used to estimate Bmax from a single study in a single animal and has potential for direct application in human studies using positron emission tomography.


Asunto(s)
Encéfalo/metabolismo , Naltrexona/análogos & derivados , Receptores Opioides/metabolismo , Animales , Agua Corporal/metabolismo , Cerebelo/metabolismo , Cinética , Masculino , Naltrexona/sangre , Naltrexona/líquido cefalorraquídeo , Naltrexona/farmacocinética , Lóbulo Parietal/metabolismo , Ratas , Ratas Endogámicas , Tálamo/metabolismo , Distribución Tisular
14.
J Cereb Blood Flow Metab ; 11(2): 183-203, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1847702

RESUMEN

[3H]Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model (Sawada et al., 1990a) and a classical compartmental pharmacokinetic model (Wong et al., 1986a) were compared. The models included different assumptions for transport across the blood-brain barrier (BBB); estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium constant varied modestly in different brain structures (Keq = 3-9), whereas the binding potential (BP) varied over a much broader range (BP = 0.6-32). In vivo estimates of the opioid receptor dissociation constant were similar for different brain structures (KD = 2.1-5.2 nM), whereas the apparent receptor density (Bmax) varied between 1 (cerebellum) and 78 (thalamus) pmol/g of brain. The receptor dissociation rate constants in cerebrum (k4 = 0.08-0.16 min-1; koff = 0.16-0.23 min-1) and brain vascular permeability (PS = 1.3-3.4 ml/min/g) are sufficiently high to achieve equilibrium conditions within a reasonable period of time. Graphical analysis (Patlak and Blasberg, 1985) of the data is inappropriate due to the high tissue-loss rate constant (kb = 0.03-0.07 min-1) for CF in brain. From these findings, CF should be a very useful opioid receptor ligand for the estimation of the receptor binding parameters in human subjects using [18F]CF and positron emission tomography.


Asunto(s)
Encéfalo/metabolismo , Naltrexona/análogos & derivados , Receptores Opioides/metabolismo , Animales , Autorradiografía , Transporte Biológico , Barrera Hematoencefálica , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Cromatografía Líquida de Alta Presión , Humanos , Inyecciones Intraarteriales , Inyecciones Intravenosas , Cinética , Masculino , Naltrexona/administración & dosificación , Naltrexona/metabolismo , Naltrexona/farmacocinética , Ratas , Ratas Endogámicas , Tálamo/metabolismo , Distribución Tisular , Tritio
15.
Neurology ; 44(2): 315-8, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8309582

RESUMEN

We studied two patients from a Japanese family with carpal tunnel syndrome (CTS). The biopsy samples obtained during CTS surgical release revealed deposits of amyloid that stained with antihuman transthyretin (TTR) antiserum. Single-strand conformation polymorphism analysis and sequence analysis of polymerase chain reaction (PCR)-amplified exons of the proband's TTR gene revealed a point mutation resulting in a substitution of histidine for tyrosine at position 114. The mutation was confirmed by PCR-primer-induced restriction analysis. Our findings account for clinical heterogeneity of TTR-derived amyloidosis, and suggest the importance of substitution itself for deposits of amyloid in CTS.


Asunto(s)
Amiloide/biosíntesis , Síndrome del Túnel Carpiano/genética , Variación Genética , Histidina , Mutación Puntual , Prealbúmina/genética , Tirosina , Anciano , Secuencia de Aminoácidos , Amiloide/análisis , Secuencia de Bases , Síndrome del Túnel Carpiano/cirugía , ADN/química , Cartilla de ADN , Exones , Femenino , Humanos , Japón , Masculino , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Mapeo Restrictivo
16.
Cell Stress Chaperones ; 4(1): 46-53, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10467108

RESUMEN

To reveal the intracellular localization of Hsp104 in the yeast Saccharomyces cerevisiae before and after heat-shock, we performed immunoelectron microscopy after immunogold labeling with anti-Hsp104 antibody. At normal temperature (25 degrees C), a small amount of Hsp104 was located in the cytoplasm and nucleus. On exposure to mild heat-shock at 40 degrees C, protein aggregates appeared in the cytoplasm and nucleus, and Hsp104 increased around the aggregates with increasing time of the mild heat-shock treatment. Moreover, at lethal heat-shock temperature (51 degrees C) for 20 min after mild heat treatment at 40 degrees C, the intracellular localization of Hsp104 and intracellular structures were similar to those of the mild heat-shocked cells. However, in the lethally heat-shocked cells, certain intracellular structures were destroyed, and Hsp104 was not expressed. In the hsp104 null mutant strain Deltahsp104 which was treated at 40 degrees C, Hsp104 was not localized around the aggregates. Additionally, in the Deltahsp104 strain, even mild heat-shocked cells at 37 degrees C or 40 degrees C, showed destruction of intracellular structure compared to the wild-type strain. Our data suggest the following: (1) Hsp104 is associated closely with protein aggregates during heat-shock treatment, (2) Hsp104 is important for maintenance of the intracellular structure under lethal heat-shock conditions, (3) acquisition of thermotolerance depends on the amount of Hsp104 produced during mild heat-shock treatment.


Asunto(s)
Proteínas Fúngicas/metabolismo , Proteínas de Choque Térmico/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/ultraestructura , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Genes Fúngicos , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Calor , Sustancias Macromoleculares , Microscopía Inmunoelectrónica , Mutación , Saccharomyces cerevisiae/genética
17.
Phys Rev Lett ; 84(14): 3049-52, 2000 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-11019009

RESUMEN

Synchronization of mutually coupled chaotic lasers has been demonstrated in a microchip LiNdP4O12 laser array with self-mixing feedback modulation. An abrupt transition to synchronized chaos by way of "phase squeezing" was observed when coupling between the two lasers was increased. This phenomenon is well reproduced by numerical calculations using model equations. It is also shown that low energy variation as well as high disorder are concurrently established in synchronized chaos.

18.
Org Lett ; 3(6): 815-8, 2001 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-11263889

RESUMEN

A convenient method for the oxidation of nucleoside phosphites into phosphates under nonbasic and nonaqueous conditions using commercially available ethyl(methyl)dioxirane has been developed. This oxidation is effective with both N-protected and N-unprotected strategies.


Asunto(s)
Óxido de Etileno , Nucleósidos/química , Nucleótidos/química , Nucleótidos/síntesis química , Fosfitos/química , Óxido de Etileno/análogos & derivados , Indicadores y Reactivos , Estructura Molecular , Oxidación-Reducción
19.
Virchows Arch ; 428(1): 37-46, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8646367

RESUMEN

Immunolocalization of matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in periarticular tissues of beta 2-microglobulin amyloidosis patients was investigated. MMP-1 (interstitial collagenase) the most strongly expressed of the MMPs, was localized in the synovial lining cells, mesenchymal cells in granulation tissue and nodular amyloid deposits, and chondrocytes within areas of cartilage erosion. Expression of MMP-1 was correlated with the degree of macrophage infiltration and synovial cell hyperplasia, but it was not correlated with the degree of amyloid deposition or haemodialysis period. Expression of MMP-1 appeared more intense than that of TIMP-1 and TIMP-2 in highly inflammatory cases. MMP-2 was mildly expressed in the interstitial fibroblasts and MMP-3 was faintly stained in the extracellular matrix of the synovial membrane. MMP-9 (gelatinase B) was found to be strongly positive in the osteoclasts which increased in the progressing osteolytic lesion from the destructive arthropathy. These results suggest involvement of MMPs in inflammation with an imbalance between expression of MMPs and TIMPs being closely related to pathogenesis of the destructive arthropathy.


Asunto(s)
Amiloidosis/etiología , Amiloidosis/patología , Cartílago Articular/patología , Metaloendopeptidasas/efectos adversos , Metaloendopeptidasas/biosíntesis , Diálisis Renal/efectos adversos , Microglobulina beta-2/metabolismo , Amiloidosis/enzimología , Artritis Reumatoide/enzimología , Artritis Reumatoide/etiología , Artritis Reumatoide/patología , Cartílago Articular/enzimología , Glicoproteínas/metabolismo , Humanos , Metaloendopeptidasas/antagonistas & inhibidores , Inhibidores de Proteasas/metabolismo , Sinovitis/enzimología , Sinovitis/etiología , Sinovitis/patología , Inhibidores Tisulares de Metaloproteinasas
20.
Virchows Arch ; 427(1): 49-59, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7551345

RESUMEN

Changes in extracellular matrices of articular tissue, intervertebral discs and systemic organs in patients with haemodialysis-related amyloidosis were investigated by immunohistochemical and biochemical examination of proteoglycans. Increased staining for chondroitin sulfate (CS) was detected in the amyloid deposits of all patients, ranging from early to advanced stages. Degenerative tissue changes around early-stage amyloid deposits in the intervertebral discs also showed positive staining for CS. Heparan sulfate (HS) was detected in amyloid deposits, especially in the synovial membrane. Biochemical analysis of connective tissues containing amyloid supported the immunohistochemical studies; CS was the major glycosaminoglycan species in these tissues, accounting for 55-81% of the total glycosaminoglycans. Although previous studies have stressed the importance of HS in amyloidogenesis, the present study showed that CS, which increased significantly in articular tissues associated with mechanical stress, also has a close relationship with amyloidogenesis.


Asunto(s)
Amiloidosis/metabolismo , Tejido Conectivo/metabolismo , Matriz Extracelular/metabolismo , Proteoglicanos/análisis , Diálisis Renal/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Amiloidosis/etiología , Amiloidosis/patología , Tejido Conectivo/patología , Matriz Extracelular/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad
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