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1.
J Phys Chem A ; 128(7): 1241-1249, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38324399

RESUMEN

The recent implementation of attosecond and few-femtosecond X-ray pump/X-ray probe schemes in large-scale free-electron laser facilities has opened the way to visualize fast nuclear dynamics in molecules with unprecedented temporal and spatial resolution. Here, we present the results of theoretical calculations showing how polarization-averaged molecular-frame photoelectron angular distributions (PA-MFPADs) can be used to visualize the dynamics of hydrogen migration in methanol, ethanol, propanol, and isopropyl alcohol dications generated by X-ray irradiation of the corresponding neutral species. We show that changes in the PA-MFPADs with the pump-probe delay as a result of intramolecular photoelectron diffraction carry information on the dynamics of hydrogen migration in real space. Although visualization of this dynamics is more straightforward in the smaller systems, methanol and ethanol, one can still recognize the signature of that motion in propanol and isopropyl alcohol and assign a tentative path to it. A possible pathway for a corresponding experiment requires an angularly resolved detection of photoelectrons in coincidence with molecular fragment ions used to define a molecular frame of reference. Such studies have become, in principle, possible since the first XFELs with sufficiently high repetition rates have emerged. To further support our findings, we provide experimental evidence of H migration in ethanol-OD from ion-ion coincidence measurements performed with synchrotron radiation.

2.
Oral Dis ; 24(7): 1161-1167, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29356251

RESUMEN

Tissue engineering is a promising method for the regeneration of oral and maxillofacial tissues. Proper selection of a cell source is important for the desired application. This review describes the discovery and usefulness of dedifferentiated fat (DFAT) cells as a cell source for tissue engineering. Dedifferentiated Fat cells are a highly homogeneous cell population (high purity), highly proliferative, and possess a multilineage potential for differentiation into various cell types under proper in vitro inducing conditions and in vivo. Moreover, DFAT cells have a higher differentiation capability of becoming osteoblasts, chondrocytes, and adipocytes than do bone marrow-derived mesenchymal stem cells and/or adipose tissue-derived stem cells. The usefulness of DFAT cells in vivo for periodontal tissue, bone, peripheral nerve, muscle, cartilage, and fat tissue regeneration was reported. Dedifferentiated Fat cells obtained from the human buccal fat pad (BFP) are a minimally invasive procedure with limited esthetic complications for patients. The BFP is a convenient and accessible anatomical site to harvest DFAT cells for dentists and oral surgeons, and thus is a promising cell source for oral and maxillofacial tissue engineering.


Asunto(s)
Adipocitos/citología , Desdiferenciación Celular , Regeneración , Células Madre/citología , Ingeniería de Tejidos , Proliferación Celular , Nervio Facial/fisiología , Humanos , Periodoncio/fisiología , Recolección de Tejidos y Órganos
3.
Eur J Dent Educ ; 22(3): e350-e357, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29120509

RESUMEN

INTRODUCTION: Every dental provider needs to be educated about medical emergencies to provide safe dental care. Simulation training is available with simulators such as advanced life support manikins and robot patients. However, the purchase and development costs of these simulators are high. We have developed a simulation training course on medical emergencies using an inexpensive software application. The purpose of this study was to evaluate the educational effectiveness of this course. MATERIALS AND METHODS: Fifty-one dental providers participated in this study from December 2014 to March 2015. Medical simulation software was used to simulate a patient's vital signs. We evaluated participants' ability to diagnose and treat vasovagal syncope or anaphylaxis with an evaluation sheet and conducted a questionnaire before and after the scenario-based simulation training. RESULTS: The median evaluation sheet score for vasovagal syncope increased significantly from 7/9 before to 9/9 after simulation training. The median score for anaphylaxis also increased significantly from 8/12 to 12/12 (P < .01). For the item "I can treat vasovagal syncope/anaphylaxis adequately," the percentage responding "Strongly agree" or "Agree" increased from 14% to 56% for vasovagal syncope and from 6% to 42% for anaphylaxis with simulation training. CONCLUSIONS: This simulation course improved participants' ability to diagnose and treat medical emergencies and improved their confidence. This course can be offered inexpensively using a software application.


Asunto(s)
Simulación por Computador , Educación en Odontología , Medicina de Emergencia/educación , Entrenamiento Simulado , Programas Informáticos , Anafilaxia/diagnóstico , Anafilaxia/terapia , Competencia Clínica , Educación en Odontología/economía , Educación en Odontología/métodos , Tratamiento de Urgencia , Femenino , Humanos , Japón , Masculino , Programas Informáticos/economía , Encuestas y Cuestionarios , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/terapia
4.
J Appl Microbiol ; 118(4): 873-80, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25626919

RESUMEN

AIMS: To evaluate the antimicrobial properties of the main Ginjo-flavour components of sake, volatile isoamyl acetate and isoamyl alcohol. METHODS AND RESULTS: Volatile isoamyl acetate and isoamyl alcohol both inhibited growth of the five yeast and 10 bacterial test strains. The minimum inhibitory dose and minimum bactericidal (fungicidal) dose of isoamyl acetate were higher than those of isoamyl alcohol. Escherichia coli and Acetobacter aceti were markedly sensitive to isoamyl acetate and isoamyl alcohol. In E. coli exposed to isoamyl acetate for 5 h, changes in expression were noted in proteins involved in sugar metabolism (MalE, MglB, TalB and PtsI), tricarboxylic acid cycle (AceA, Pfl and AcnB) and protein synthesis (EF-Tu, EF-G, and GlyS). Expression of acid and alcohol stress-response proteins was altered in E. coli exposed to isoamyl acetate. Esterase activity was detected in E. coli, suggesting that isoamyl acetate was hydrolyzed to acetic acid and isoamyl alcohol. Acetic acid and isoamyl alcohol damaged E. coli cell membranes and inactivated membrane proteins, impairing respiration. CONCLUSIONS: Volatile isoamyl acetate and isoamyl alcohol were effective in inactivating various micro-organisms, and antimicrobial mechanism of volatile isoamyl acetate against E. coli was clarified based on proteome analysis. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report to examine the antimicrobial mechanism of volatile organic compound using proteome analysis combining two-dimensional difference gel electrophoresis with peptide mass fingerprinting.


Asunto(s)
Aromatizantes/farmacología , Pentanoles/farmacología , Vino/análisis , Bacterias/efectos de los fármacos , Aromatizantes/análisis , Pentanoles/análisis , Factor Tu de Elongación Peptídica/metabolismo , Levaduras/efectos de los fármacos
5.
Clin Nephrol ; 75(4): 384-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21426895

RESUMEN

A 62-year-old female was admitted to our hospital for investigation of acute progressive renal insufficiency and a systemic inflammatory reaction, despite treatment with several antibiotics. Laboratory data revealed severe renal insufficiency and positive titers for the myeloperoxidase anti-neutrophil cytoplasmic and anti-glomerular basement membrane antibodies. The deterioration of her general status did not allow us to perform the renal biopsy. Although corticosteroid therapy, hemodialysis, and plasma exchange were concomitantly initiated, pulmonary hemorrhage occurred several days after admission. Mechanical ventilation support was provided and continuous hemodiafiltration was carried out, following which the respiratory failure improved immediately. However, she developed clinical depression and suicidal behavior under the intensive therapy. Therefore, plasma exchange was discontinued and corticosteroid was tapered as quickly as possible. Four months after admission, platelet transfusion and short-term mechanical ventilation support improved the pulmonary hemorrhage; however, her mental status deteriorated despite psychiatric consultation and treatment with a tranquilizer. Thereafter, severe and serious systemic infection due to various pathogens including Staphylococcus aureus, Cytomegalovirus, Pneumocystis jiroveci, Pseudomonas aeruginosa, and Bacteroides recurred, and she died from systemic invasive aspergillosis (IA). We suspected severe immunosuppression caused by various factors, such as predonisolone administration, chronic renal failure on maintenance hemodialysis, depression, and malnutrition due to chronic inflammation and granulocytopenia as a side effect of ganciclovir. When treating rapidly progressive glomerulonephritis, immunosuppressive status should be carefully monitored regarding not only the dosage of therapeutic regimen but also the mental health status and nutrition of the patient.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular/complicaciones , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/inmunología , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Autoanticuerpos/inmunología , Infecciones Bacterianas/inmunología , Virosis/inmunología , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/terapia , Resultado Fatal , Femenino , Glucocorticoides/efectos adversos , Glucocorticoides/uso terapéutico , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Desnutrición/complicaciones , Persona de Mediana Edad , Intercambio Plasmático/efectos adversos , Prednisolona/efectos adversos , Prednisolona/uso terapéutico , Diálisis Renal/efectos adversos
6.
Water Sci Technol ; 62(10): 2321-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21076218

RESUMEN

The feasibility of an electrochemically assisted Fenton treatment using a Fenton-type reaction of ferrous iron (Fe(2 + )) and hypochlorous acid (HOCl) is discussed in this research. The reactor used was composed of an undivided single cell with a ruthenium dioxide-coated titanium anode and a stainless steel cathode, in which Fe(2 + ) and HOCl were catalytically regenerated from ferric iron at the cathode and chloride ion at the anode, respectively. Although the reactor functioned well, the degradation rate of 1,4-dioxane as a hydroxyl radical probe decreased at the current density more than 6.92 mA cm(-2). The decrease in degradation rate was inferred to be caused by the vain consumption of hydroxyl radicals by excess HOCl and the deposition of ferric hydroxide on the cathode at relatively high current density. The current efficiency of 1,4-dioxane removal remained more than 90% at the current density less than 6.92 mA cm(-2) and the iron concentration not less than 1.0 mmol L(-1). Consequently, this technique is thought to be applicable to the treatment of wastewater containing high concentration of chloride ion such as landfill leachate, scrubber wastewater from incineration plants, etc.


Asunto(s)
Técnicas Electroquímicas/métodos , Peróxido de Hidrógeno/química , Ácido Hipocloroso/química , Hierro/química , Purificación del Agua/métodos , Oxidación-Reducción
7.
Water Sci Technol ; 62(5): 1022-7, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20818041

RESUMEN

The effect of active control of electric potential of filter medium on depth filtration was explored experimentally. Activated carbon particles were selected as the conductive filter medium. The filter medium potential was controlled with an external DC power supply. Kaolin particles were used as the model suspended solid. The activated carbon and kaolin had negative zeta potential around neutral pH. When the filter medium potential against a counter electrode was greater than or equal to + 0.2 V, rejection rate of particles was 1.8 times higher than that when the potential was less than + 0.2 V. Thus adsorption of particles by interaction of electric double layers was enhanced by maintaining a positive charge on the filter media. Desorption of kaolin trapped on the filter media was also confirmed by changing the filter medium potential from positive to negative. The percentage of kaolin particles desorbed was 11% of the kaolin trapped on the filter media. The desorption rate was not high, but this technique will enhance refreshment of the filter media when combined with back washing.


Asunto(s)
Conductividad Eléctrica , Filtración/instrumentación , Filtración/métodos , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Carbono/química , Concentración de Iones de Hidrógeno , Caolín/química , Contaminantes Químicos del Agua/química , Contaminación Química del Agua/prevención & control
8.
Science ; 276(5317): 1378-82, 1997 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-9190677

RESUMEN

Spectroscopic and photometric evidence indicates that Type Ia supernovae (SNe Ia) are the thermonuclear explosions of accreting white dwarfs. However, the progenitor binary systems and hydrodynamical models for SNe Ia are still controversial. The relatively uniform light curves and spectral evolution of SNe Ia have led to their use as a standard candle for determining cosmological parameters, such as the Hubble constant, the density parameter, and the cosmological constant. Recent progress includes the calibration of the absolute maximum brightness of SNe Ia with the Hubble Space Telescope, the reduction of the dispersion in the Hubble diagram through the use of the relation between the light curve shape and the maximum brightness of SNe Ia, and the discovery of many SNe Ia with high red shifts.


Asunto(s)
Astronomía , Fenómenos Astronómicos , Carbono/química , Elementos Químicos , Evolución Planetaria , Medio Ambiente Extraterrestre , Luz , Física Nuclear
9.
Nanotechnology ; 20(6): 065303, 2009 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-19417379

RESUMEN

Regularly arrayed microstrip regions of width approximately 1.4 microm and length extending up to approximately 5 mm, consisting of ZnO nanoparticles (NPs) of diameter approximately 50 nm, were fabricated on silica substrates by a two-step process: i.e., selected-area ion implantation and thermal oxidation. The implantation of 60 keV Zn ions in periodic microstrip regions via a resist mask generated periodic grooves with large wings on the surface of silica glass, which can be ascribed to the radiation-induced plastic deformation of silica and sputtering loss. This is the lowest record of the electronic energy loss (S(e)) value to induce the radiation-induced plastic deformation of silica, while no or very low threshold energy has been predicted from a recent study. After thermal oxidation at 700 degrees C for 1 h, the groove structures with the wings disappeared, and periodic microstrips of ZnO nanoparticle aggregates up to 5 mm long appeared on the surface of the substrate. A clear free-exciton peak due to ZnO NPs is observed from these microstrip structures both in optical absorption and photoluminescence spectra.

10.
Clin Nephrol ; 67(3): 182-7, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17390743

RESUMEN

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary systemic arteriopathy presenting with migraines, mood disorders, focal neurologic deficits, recurrent ischemic attacks and dementia in young adults. The genesis of this disease relates to missense mutation of the Notch3 gene. We report here a newly identified CADASIL patient and discuss unique vascular lesions observed in the kidney. A 64-year-old female was admitted to our hospital for the investigation of proteinuria, hematuria and progressive neurological abnormalities. Her mother and brother died of cerebral infarction at a relatively young age despite a lack of apparent risk factors for arteriosclerosis. Over the past 4 months before admission, she had suffered from frequent transient ischemic attacks despite appropriate antiplatelet therapy. Blood examination revealed mild renal insufficiency and urinalysis revealed moderate protein excretion and dysmorphic hematuria. Magnetic resonance imaging of the brain revealed multiple infarcts and leukoencephalopathy. Histopathological analysis of the kidney revealed focal segmental mesangial proliferation, the loss and degeneration of arterial medial smooth muscle cells and arterial intimal thickening. Immunofluorescence analysis of glomeruli revealed IgA deposition in the mesangial area. Electron microscope analysis revealed electron-dense deposition also in the mesangial area. In addition, granular osmophilic material (GOM) was observed in the extraglomerular mesangial area and around the vascular smooth muscle cells. Genetic analysis of Notch3 revealed an R141C missense mutation and she was diagnosed with CADASIL complicated with IgA nephropathy. In immunohistological analysis, Notch3 stains were positive in vascular smooth muscle cells of the interlobular arteries and both afferent and efferent arterioles, and weak in the glomerular mesangial area. Antihypertensive treatment using angiotensin II receptor blocker and a low protein diet were initiated, and her urinary protein excretion decreased to 0.2 g/day. However, due to the progression of her neurological abnormalities, she became socially withdrawn. In CADASIL, GOM, abnormal accumulation of Notch3 ectodomain, is thought to induce the degeneration and loss of vascular smooth muscle cells and subsequent intimal thickening. Analysis of our cases provided that these morphological abnormalities were also observed in the CADASIL patient kidney.


Asunto(s)
CADASIL/complicaciones , Angiopatía Amiloide Cerebral Familiar/complicaciones , Glomerulonefritis por IGA/etiología , Antagonistas de Receptores de Angiotensina , Antihipertensivos , Biopsia , CADASIL/diagnóstico , CADASIL/genética , Angiopatía Amiloide Cerebral Familiar/diagnóstico , Angiopatía Amiloide Cerebral Familiar/genética , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Glomerulonefritis por IGA/tratamiento farmacológico , Glomerulonefritis por IGA/patología , Humanos , Inmunohistoquímica , Imagen por Resonancia Magnética , Células Mesangiales/ultraestructura , Microscopía Electrónica , Persona de Mediana Edad , Mutación Missense , Receptor Notch3 , Receptores Notch/genética , Piel/ultraestructura
11.
Clin Nephrol ; 66(6): 447-54, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17176917

RESUMEN

Renal deterioration often occurs in cases of infectious endocarditis (IE), but, IE- associated nephritis with rapidly progressive glomerulonephritis (RPGN) is rare. Patients with severe infection (e.g., IE) sometimes show positivity for cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA). Therefore, diagnosis and treatment are very difficult in cases of RPGN with IE and positivity for C-ANCA. Such cases are rare, only 12 have been reported in the English literature. Herein, we describe the case of a 50-year-old man who presented with RPGN with IE and tested positively for C-ANCA. He was referred to our hospital because of leg edema, purpura and renal dysfunction. Laboratory tests revealed serum creatinine elevation and positivity for C-ANCA and proteinase 3-specific (PR3)-ANCA. RPGN and acute renal failure were diagnosed. Hemodialysis and steroid therapy were started. Streptococcus oralis was isolated by blood culture. Transthoracic echocardiography revealed grade III mitral valve insufficiency with two vegetations. Therefore, IE was diagnosed. The steroid therapy was stopped, and antibiotic therapy was begun. Because there was no improvement, surgical therapy was performed. The operation was successful, but the patient died of brain hemorrhage. Our experience in this case indicates C/PR3-ANCA positive RPGN must be ruled out in patients with infectious disease, particularly IE, together with renal symptoms, and renal biopsy should be performed.


Asunto(s)
Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Endocarditis Bacteriana/complicaciones , Glomerulonefritis/inmunología , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Anticuerpos Anticitoplasma de Neutrófilos/sangre , Ecocardiografía , Endocarditis Bacteriana/sangre , Endocarditis Bacteriana/inmunología , Resultado Fatal , Glomerulonefritis/sangre , Glomerulonefritis/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/etiología , Insuficiencia de la Válvula Mitral/cirugía
12.
Plant Physiol ; 110(1): 89-96, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12226172

RESUMEN

The recessive floury-2 (flo-2) locus of rice (Oryza sativa L.), which is located on chromosome 4, causes a strong reduction in expression of the gene encoding an isoform of branching enzyme RBE1 in immature seeds 10 d after flowering. Mapping of the RBE1 gene demonstrated the localization on rice chromosome 6, suggesting that the wild-type Floury-2 (Flo-2) gene regulates RBE1 gene expression in trans. However, reduced expression of the genes encoding some other starch-synthesizing enzymes, including another isoform of branching enzyme RBE3 and granule-bound starch synthase, was also found in the flo-2 seeds. In spite of the low level of RBE1 gene expression in the immature seeds of the flo-2 mutants, the RBE1 gene was equally expressed in the leaves of the wild type and flo-2 mutants. Thus, these results imply that the Flo-2 gene may co-regulate expression of some of the genes participating in starch synthesis possibly in a developing seed-specific manner.

13.
Environ Technol ; 26(10): 1161-71, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16342538

RESUMEN

The effects of hydrodynamic conditions on the production of hydroxyl radicals (*OH) during electrochemical treatment using a titanium coated by platinum anode and a stainless steel cathode are discussed in this paper. The sample used was ultra-pure water containing 200 mM of 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The amount of *OH for treatment was measured using electron spin resonance spectrometry coupled with DMPO spin trapping. Under constant hydrodynamic conditions, the production rate of the *OH spin adduct (DMPO-OH) increased with the terminal potential. This result was caused by the change in the electric current density at the anode, which was proportional to the rate of production of DMPO-OH. Increasing the linear velocity of water in an electrolytic cell promoted the production of DMPO-OH by two effects, namely, by the enhancement of ion transportation and the promotion of DMPO transfer from the bulk to the anode. The former effect emerged when the DMPO concentration near the anode was not insignificant in comparison with the DMPO concentration in the bulk, that is, when the overall rate-determining step was the electron transfer at the anode. The latter effect emerged when the DMPO concentration near the anode was much lower than the DMPO concentration in the bulk, that is, when the overall rate-determining step was the diffusion of DMPO from the bulk to the anode. In addition, the latter effect was found to be proportional to the square root of the linear velocity of water in the electrolytic cell.


Asunto(s)
Electrólisis/métodos , Hidróxidos/química , Movimientos del Agua , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Electrodos , Platino (Metal) , Detección de Spin , Titanio
14.
Biotechniques ; 31(5): 1042, 1044, 1048-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11730011

RESUMEN

We have developed a method to overcome sequencing problems caused by the presence of homopolymer stretches, such as polyA/T, in cDNA libraries. PolyA tails are shortened by cleaving before cDNA cloning with type IIS restriction enzymes, such as GsuI, placed next to the oligo-dT used to prime the polyA tails of mRNAs. We constructed four rice Cap-Trapper-selected, full-length normalized cDNA libraries, of which the average residual polyA tail was 4 bases or shorter in most of the clones analyzed Because of the removal of homopolymeric stretches, libraries prepared with this method can be used for direct sequencing and transcriptional sequencing without the slippage observed for libraries prepared with currently available methods, thus improving sequencing accuracy, operations, and throughput.


Asunto(s)
ADN Complementario/química , Biblioteca de Genes , Poli A/química , Análisis de Secuencia de ADN/métodos , Animales , Ratones , Ratones Endogámicos C57BL , Transfección
15.
Cell Transplant ; 10(4-5): 387-92, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11549059

RESUMEN

With the development of biotechnology, hepatic support by a hybrid artificial liver (HAL) using hepatocytes has been given much attention. Because the availability of human livers is limited, we have established a tightly regulated immortal human hepatocyte cell line, NKNT-3, for developing HAL. Because high-density cell culture allows the compactness of the HAL device and its easy use under emergency circumstances, we have developed cell adhesive GRGDS peptide-containing cellulose microspheres (GRGDS/CMS). The GRGDS/CMS efficiently immobilized NKNT-3 cells within 24 h in a stirred suspension culture. Electron microscopic examinations demonstrated glycogen granules and well-developed endoplasmic reticulum and mitochondria in NKNT-3 cells attached to the GRGDS/CMS. The cells showed ammonia clearance activity, whereas HepG2-transformed human liver cells did not remove the loaded ammonia. An efficient adenoviral delivery of the lacZ reporter gene was performed in GRGDS/CMS-immobilized NKNT-3 cells. In this study we present rapid immobilization of NKNT-3 immortal human hepatocytes using cellulose microspheres carrying GRGDS peptides. These microspheres satisfied immediate preparation of NKNT-3 cells in sufficient quantity and of adequate quality.


Asunto(s)
Adhesión Celular/fisiología , Células Inmovilizadas , Hepatocitos/fisiología , Hígado Artificial , Microesferas , Oligopéptidos , Amoníaco/metabolismo , Técnicas de Cultivo de Célula/métodos , Línea Celular , Tamaño de la Célula , Celulosa/metabolismo , Técnicas de Transferencia de Gen , Hepatocitos/ultraestructura , Humanos , Oligopéptidos/metabolismo , Factores de Tiempo
16.
FEMS Microbiol Lett ; 132(1-2): 91-4, 1995 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7590170

RESUMEN

The phylogenetic position of an acidophilic chemo-organotrophic menaquinone-containing bacterium, Acidobacterium capsulatum, was studied on the basis of 16S rRNA gene sequence information. A. capsulatum showed the highest level of sequence similarity to Heliobacterium chlorum, a member of the Gram-positive group, yet this level was only 81%. Distance matrix tree analysis suggested that A. capsulatum belongs to a unique lineage deeply branching from the Chlamydia-Planctomyces group or from the Gram-positive line.


Asunto(s)
Evolución Molecular , Bacterias Gramnegativas Quimiolitotróficas/genética , Filogenia , Vitamina K , Secuencia de Bases , Bacterias Gramnegativas Quimiolitotróficas/metabolismo , Datos de Secuencia Molecular , ARN Bacteriano/química , ARN Ribosómico 16S/química , Análisis de Secuencia de ARN , Vitamina K/biosíntesis
17.
Clin Nephrol ; 59(6): 423-8, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12834173

RESUMEN

BACKGROUND: An accessible non-invasive method for evaluating renal regional blood flow in real time is highly desirable in the clinical setting. Recent progress in ultrasonography with microbubble contrast has allowed quantification of regional blood flow in animal models. AIMS: Goal ofthis study was to establish a convenient contrast--enhanced harmonic ultrasonography (CEHU) method for evaluating renal cortical blood flow in humans. METHODS: We carried out intermittent second harmonic imaging in 9 healthy volunteers. Pulse interval was progressively decreased from 4 s - 0.2 s during continuous venous infusion of the microbubble contrast agent. RESULTS: Pulse interval versus CEHU-derived acoustic intensity plots provided microbubble velocity (MV) and fractional vascular volume (FVV) during renal cortical perfusion in humans. Low-dose dopamine infusion (2 microg/min/kg) resulted in a significant increase in MV which correlated well with the increase in total renal blood flow (RBF) determined by a conventional study of p-aminohippurate clearance (C(PAH)) (r = 0.956, p < 0.0001). Although FVV was not significantly increased, alterations in CEHU-derived renal cortical blood flow calculated by the products of MV and FVV were also correlated with alterations in total RBF (r = 0.969, p < 0.0001). Thus, low-dose dopamine infusion increases renal cortical blood flow observed in CEHU, mainly by increasing MV. CONCLUSIONS: The present study shows that renal cortical blood flow in humans can be measured non-invasively by CEHU and that CEHU can be used for quantitatively evaluating changes induced by a therapeutic agent such as dopamine in flow velocity and in FVV.


Asunto(s)
Riñón/diagnóstico por imagen , Circulación Renal , Adulto , Medios de Contraste , Dopamina , Femenino , Humanos , Riñón/efectos de los fármacos , Corteza Renal/irrigación sanguínea , Masculino , Circulación Renal/efectos de los fármacos , Ultrasonografía
18.
Clin Nephrol ; 61(2): 144-50, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14989635

RESUMEN

We describe the case of a 51-year-old man with hepatitis C virus (HCV) infection and a 3-month history of facial edema. Laboratory tests upon admission for renal biopsy showed normal renal function and normocomplementemia. Serum HCV antibody (Ab) and cryoglobulin were positive. Renal biopsy specimens showed features of membranous glomerulonephritis. The likely cause was immune complex-mediated glomerulonephritis associated with HCV infection. Reports of similar cases in the literature show the normocomplementemia and negative or slightly positive cryoglobulins observed in our case as well as seropositivity for circulating immune complexes containing HCV RNA. In our case, electron microscopic examination of the subepithelial glomerular lesions revealed massive virus-like particles within unusual multilayers of electron-dense deposits (EDDs), suggesting the existence of HCV in the glomeruli. In the addition to the unique histopathological feature the presence of La/SS-B antibody in his serum indicated an abnormal immune response associated with HCV. We advise him to undergo the therapy with new type of IFN such as pegIFN-alpha2a and/or anti-viral agent like ribavirin to achieve clinical and histopathological improvement.


Asunto(s)
Glomerulonefritis Membranosa/virología , Hepatitis C/complicaciones , Glomerulonefritis Membranosa/patología , Glomerulonefritis Membranosa/terapia , Hepatitis C/terapia , Humanos , Masculino , Persona de Mediana Edad
19.
Clin Nephrol ; 57(1): 69-73, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11837804

RESUMEN

An otherwise healthy 20-year-old woman presented with an erythematous rash on her face as well as arthralgia and anemia. She also had systemic edema, proteinuria and hypertension. Laboratory data on admission showed hypocomplementemia, human parvovirus B 19 (HPV) DNA and both immunoglobulin (Ig) M and IgG antibodies to HPV in her serum. Renal biopsy specimens showed features of endocapillary glomerulonephritis under light microscopy. Electron microscopy showed massive subendothelial electron-dense deposits. No cause was probable other than immune complex-mediated glomerulonephritis associated with HPV infection. In a review of this and similar cases reported in the literature, several characteristic features come to light: female dominance, onset in the second or third decade of life, hypocomplementemia, histologic renal endocapillary and/or mesangioproliferative glomerulonephritis with subendothelial deposits and spontaneous recovery.


Asunto(s)
Glomerulonefritis/virología , Infecciones por Parvoviridae , Parvovirus B19 Humano , Adulto , Anemia/etiología , Artralgia/virología , Biopsia , Proteínas del Sistema Complemento/deficiencia , Eritema/virología , Dermatosis Facial/virología , Femenino , Glomerulonefritis/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Infecciones por Parvoviridae/inmunología
20.
Hum Cell ; 13(4): 229-35, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11329939

RESUMEN

Currently patients with liver failure have been treated with a various liver support systems including a whole liver perfusion, a non-biological artificial liver, and a biohybrid artificial liver. In a hepatocyte-based bioreactor, porcine hepatocytes or transformed human liver tumor cells have been utilized because of the ease of preparation. According to the clinical data reported as of now, satisfactory results have not been obtained from the use of currently available liver support devices. One of the problems is limited availability of primary human liver cells for developing live support systems because of the shortage of human liver. To resolve this issue, human hepatocytes were immortalized with a retroviral vector SSR#69 which contained the genes of simian virus 40 large T antigen (SV40Tag) and herpes simplex virus-thymidine kinase (HSV-TK). One of the immortal cell lines, NKNT-3, showed the gene expression of differentiated liver functions, grew steadily in chemically defined serum-free CS-C medium, and doubled in number in about 48 hours. Essentially unlimited availability of NKNT-3 cells supports their clinical use for liver support devices. To realize the high density culture of NKNT-3 cells in a bioartificial liver device, we have developed cellulose microspheres (CMS) which contain cell adhesive GRGDS (Gly-Arg-Gly-Asp-Ser) peptides. Within 24 hours after starting a stirring suspension culture, GRGDS-CMS efficiently immobilized NKNT-3 cells. An electron microscopic examination demonstrated that NKNT-3 cells attached on GRGDS-CMS had well-developed mitochondria, rough reticulums, and villous extensions. In this article, we review the history of extracorporeal liver support systems and describe an attractive strategy for developing a novel extracorporeal liver assist device using NKNT-3 cells and GRGDS-coated cellulose microspheres.


Asunto(s)
Hepatocitos/citología , Hígado Artificial , Animales , Antígenos Transformadores de Poliomavirus , División Celular , Línea Celular , Celulosa , Humanos , Microesferas , Oligopéptidos , Porcinos
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