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

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-29356251

RESUMO

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.


Assuntos
Adipócitos/citologia , Desdiferenciação Celular , Regeneração , Células-Tronco/citologia , Engenharia Tecidual , Proliferação de Células , Nervo Facial/fisiologia , Humanos , Periodonto/fisiologia , Coleta de Tecidos e Órgãos
3.
Eur J Dent Educ ; 22(3): e350-e357, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29120509

RESUMO

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.


Assuntos
Simulação por Computador , Educação em Odontologia , Medicina de Emergência/educação , Treinamento por Simulação , Software , Anafilaxia/diagnóstico , Anafilaxia/terapia , Competência Clínica , Educação em Odontologia/economia , Educação em Odontologia/métodos , Tratamento de Emergência , Feminino , Humanos , Japão , Masculino , Software/economia , Inquéritos e Questionários , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/terapia
4.
J Appl Microbiol ; 118(4): 873-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25626919

RESUMO

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.


Assuntos
Aromatizantes/farmacologia , Pentanóis/farmacologia , Vinho/análise , Bactérias/efeitos dos fármacos , Aromatizantes/análise , Pentanóis/análise , Fator Tu de Elongação de Peptídeos/metabolismo , Leveduras/efeitos dos fármacos
5.
Prostate Cancer Prostatic Dis ; 15(4): 386-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22777394

RESUMO

BACKGROUND: Asymptomatic prostatic inflammation may cause increased PSA in some men, leading to unnecessary prostate biopsy. We investigated whether the differential white cell count could predict the result of prostate biopsy. METHODS: Prostate needle biopsy was carried out in 323 Japanese men with elevated PSA levels or abnormal digital rectal findings. White blood cell count (WBC), differential white cell count (neutrophils, lymphocytes, basophils, eosinophils, and monocytes), and serum C-reactive protein level were assessed for associations with biopsy findings. RESULTS: In all, 203 (62.1%) were positive for prostate cancer. WBC, neutrophil count, age, PSA, prostate volume, and PSA density (PSAD) were associated with the results of biopsy (P<0.05). Multivariate analysis showed that neutrophil count, age, PSA, prostate volume and PSAD were independent predictors. When the cut-off neutrophil count was set at 2900 µl(-1), 78 of 104 men (75.0%) with a count below this value had a positive biopsy, while 125 of 219 (57.0%) men with a count above this value were positive. The area under the receiver-operator characteristics curve (AUC) for the predicted probability of a positive biopsy for prostate cancer according to the optimum logistic model was 0.83 (95% confidence interval (CI) 0.78-0.87), while the AUC for PSA was 0.70 (95% CI 0.64-0.76) and that for PSAD was 0.79 (95% CI 0.74-0.84). CONCLUSIONS: An elevated neutrophil count may be a good indicator of a benign prostate biopsy. Men with a low neutrophil count and an increase of serum PSA should strongly be considered for biopsy.


Assuntos
Calicreínas/sangue , Neutrófilos/patologia , Antígeno Prostático Específico/sangue , Próstata , Neoplasias da Próstata , Biomarcadores Tumorais/sangue , Biópsia , Contagem de Células Sanguíneas , Proteína C-Reativa/metabolismo , Humanos , Masculino , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia
6.
Clin Nephrol ; 75(4): 384-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21426895

RESUMO

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.


Assuntos
Doença Antimembrana Basal Glomerular/complicações , Doença Antimembrana Basal Glomerular/imunologia , Anticorpos Anticitoplasma de Neutrófilos/imunologia , Autoanticorpos/imunologia , Infecções Bacterianas/imunologia , Viroses/imunologia , Doença Antimembrana Basal Glomerular/terapia , Evolução Fatal , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Desnutrição/complicações , Pessoa de Meia-Idade , Troca Plasmática/efeitos adversos , Prednisolona/efeitos adversos , Prednisolona/uso terapêutico , Diálise Renal/efeitos adversos
7.
Water Sci Technol ; 62(10): 2321-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21076218

RESUMO

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.


Assuntos
Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química , Ácido Hipocloroso/química , Ferro/química , Purificação da Água/métodos , Oxirredução
8.
Water Sci Technol ; 62(5): 1022-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20818041

RESUMO

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.


Assuntos
Condutividade Elétrica , Filtração/instrumentação , Filtração/métodos , Purificação da Água/instrumentação , Purificação da Água/métodos , Carbono/química , Concentração de Íons de Hidrogênio , Caulim/química , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle
9.
Nanotechnology ; 20(6): 065303, 2009 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-19417379

RESUMO

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.
Nanotechnology ; 19(37): 375306, 2008 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-21832550

RESUMO

Ion beams are widely used for micro/nanostructure fabrication with unique features of the energetic processes. In this work, we present a self-assembled nanostructure fabrication by ion irradiation with a patterned strain/stress field. The patterned strain/stress field is introduced by micro-Vickers indentation to amorphous SiO(2) (load = 100 mN). After irradiation of 60 keV Cu(-) ions, nanogrooves (width from 150 to 250 nm) were created at the indentation edge. Under the ion irradiation of a constant ion flux, the nanogroove size linearly increased with ion fluence from 2 × 10(16) to 1.2 × 10(17) ions cm(-2). Comparison of indented samples after irradiation and thermal annealing suggests that the nanogrooving originates from ion beam interactions with residual stress/strain by indentation and that a non-thermal effect results from the ion irradiation processes. Cross-sectional TEM analysis showed that the grooves extend over 200 nm below the surface, implying that the groove growth is not caused by surface diffusion. It is concluded from the results that the grooving is due to irradiation-induced mass transport accompanied by vacancy aggregation at the interface between the indented and non-indented areas.

11.
Kidney Int ; 72(5): 608-13, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17568783

RESUMO

Anti-glomerular basement membrane (anti-GBM)-induced glomerulonephritis involves T-helper type 1 (Th1) responses leading to rapid crescent formation. As many inflammatory and immune responses in general are affected by histamine, we examined the effects of histaminergic ligands on immune renal injury in the rat. Female Wistar-Kyoto rats were injected intraperitoneally with an antibody against the GBMs. Histaminergic ligands were then injected twice daily for 5 days after which renal function was assessed by proteinuria. Treatment with histamine led to significant dose-dependent reductions in proteinuria compared to the control antibody-injected group and markedly decreased the number of crescentic glomeruli and macrophage infiltration of the glomeruli. Furthermore, histamine significantly decreased the plasma concentration of interleukin-12, a Th1-type cytokine compared to the antibody-injected control animals. Dimaprit, an H(2)/H(4) agonist, mimicked the effects of histamine on proteinuria and crescent formation. Clozapine, an H(4) agonist, tended to mimic the effects of histamine, whereas an H(1), mepyramine, or an H(2) antagonist, ranitidine, did not reverse the protective effect of histamine. We suggest that histamine may alleviate renal injury in anti-GBM glomerulonephritis by suppressing the immune response.


Assuntos
Doença Antimembrana Basal Glomerular/tratamento farmacológico , Glomerulonefrite/tratamento farmacológico , Histamina/farmacologia , Animais , Anticorpos/administração & dosagem , Autoanticorpos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Histamina/administração & dosagem , Imunossupressores/administração & dosagem , Imunossupressores/farmacologia , Ligantes , Proteinúria , Ratos
12.
Clin Nephrol ; 67(3): 182-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17390743

RESUMO

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.


Assuntos
CADASIL/complicações , Angiopatia Amiloide Cerebral Familiar/complicações , Glomerulonefrite por IGA/etiologia , Antagonistas de Receptores de Angiotensina , Anti-Hipertensivos , Biópsia , CADASIL/diagnóstico , CADASIL/genética , Angiopatia Amiloide Cerebral Familiar/diagnóstico , Angiopatia Amiloide Cerebral Familiar/genética , Progressão da Doença , Feminino , Seguimentos , Glomerulonefrite por IGA/tratamento farmacológico , Glomerulonefrite por IGA/patologia , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Células Mesangiais/ultraestrutura , Microscopia Eletrônica , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Receptor Notch3 , Receptores Notch/genética , Pele/ultraestrutura
13.
Nanotechnology ; 18(39): 395707, 2007 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-21730432

RESUMO

Metallic zinc nanoparticles (NPs) of 5-15 nm in diameter, formed in silica glass (SiO(2)) by Zn ion implantation of 60 keV, showed a strong ultraviolet absorption peak at around 4.8 eV, which has been assigned as the surface plasmon resonance (SPR) of Zn NPs, and another small peak at 1.2 eV, which has never been reported before. To identify the origin of the 1.2 eV peak, the correlations of thermal stability between the two peaks and Zn NPs were evaluated under annealing both in a vacuum (pure thermal stability) and in oxygen gas (thermal oxidation stability). The well-correlated stability between the 1.2 eV peak, the 4.8 eV peak and Zn NPs indicates that the 1.2 eV peak is not ascribed to radiation-induced defects but to the Zn NPs. The 1.2 eV peak can be ascribed to an SPR of Zn NPs in SiO(2), because the peak satisfies the criterion of the SPR of metallic NPs. Since the 4.8 eV peak is also expected to satisfy the criterion, Zn NPs in SiO(2) have two SPRs at 1.2 and 4.8 eV.

14.
Clin Nephrol ; 66(6): 447-54, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17176917

RESUMO

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.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/imunologia , Endocardite Bacteriana/complicações , Glomerulonefrite/imunologia , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Anticorpos Anticitoplasma de Neutrófilos/sangue , Ecocardiografia , Endocardite Bacteriana/sangue , Endocardite Bacteriana/imunologia , Evolução Fatal , Glomerulonefrite/sangue , Glomerulonefrite/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/cirurgia
15.
Environ Technol ; 26(10): 1161-71, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16342538

RESUMO

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.


Assuntos
Eletrólise/métodos , Hidróxidos/química , Movimentos da Água , Purificação da Água/instrumentação , Purificação da Água/métodos , Eletrodos , Platina , Detecção de Spin , Titânio
16.
Appl Microbiol Biotechnol ; 68(2): 198-202, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15717173

RESUMO

A chlorogenate hydrolase (EC 3.1.1.42) synthesized 2-phenylethyl caffeate (2-CAPE) from 5-chlorogenic acid (5-CQA) and 2-phenylethyl alcohol (2-PA) (by transesterification), from 5-CQA and 2-phenylethyl bromide (2-PBr) (by substitution of bromine), and from caffeic acid (CA) and 2-PA or 2-PBr (by condensation) as well as hydrolysis of 5-CQA. Some reaction conditions including pH, temperature, substrate and solvent concentrates, and reaction time were optimized for the production of 2-CAPE. A maximal molar yield of 50% was achieved by transesterification, 4.7% by substitution of bromine, and 13% by condensation. Among the parameters studied for optimization, the pH of the buffer solution and concentration of 2-PA or 2-PBr affected the production of 2-CAPE. The optimum pH for the hydrolysis reaction was within the neutral range (pH 6.5), whereas the residual three reactions were only catalyzed within the acidic range (pH 3.0-4.0). The optimum concentrations of 2-PA and 2-PBr for three reactions were 5-70 vol% and no 2-CAPE was produced in the 2-PA or 2-PBr solutions containing powdered enzyme. The enzyme may bind to the caffeoyl moiety of 5-CQA or CA to form an enzyme-substrate complex. It then catalyzes four different reactions corresponding to the reaction conditions.


Assuntos
Ácido Clorogênico/química , Ácidos Cumáricos/química , Ésteres/química , Hidrolases/química , Aspergillus/enzimologia , Bromo , Ácidos Cafeicos/química , Ácidos Cafeicos/metabolismo , Ácido Clorogênico/metabolismo , Ácidos Cumáricos/síntese química , Ácidos Cumáricos/metabolismo , Esterificação , Ésteres/síntese química , Ésteres/metabolismo , Dibrometo de Etileno/metabolismo , Concentração de Íons de Hidrogênio , Hidrolases/metabolismo , Álcool Feniletílico/análogos & derivados , Álcool Feniletílico/química , Álcool Feniletílico/metabolismo
17.
Clin Nephrol ; 61(2): 144-50, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14989635

RESUMO

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.


Assuntos
Glomerulonefrite Membranosa/virologia , Hepatite C/complicações , Glomerulonefrite Membranosa/patologia , Glomerulonefrite Membranosa/terapia , Hepatite C/terapia , Humanos , Masculino , Pessoa de Meia-Idade
18.
Mol Genet Genomics ; 271(4): 468-78, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15029491

RESUMO

In order to understand the molecular mechanisms by which two types of phytohormones, brassinosteroids (BRs) and gibberellins (GAs), regulate plant growth and development, a cDNA microarray was made containing 4000 clones randomly selected from a rice cDNA library constructed from RNA isolated from seedlings treated with GA(3) and brassinolide (BL). The array was then probed to identify differences in expression using labelled cDNAs prepared from treated and control seedlings. Nine and 29 unique cDNA clones were up-regulated, while 32 and 42 unique cDNA clones were down-regulated by BL and GA(3), respectively. The predicted products of these BL- and GA-regulated genes fall into such functional categories as signal transduction, transcription, metabolism, cellular organization, and defense or anti-stress responses. Northern analysis of the selected BL- and GA(3)-regulated genes not only confirmed their BL or GA(3) dose dependent expression, but also revealed significant differences in the degree of expression in different organs and in response to other phytohormones. These results demonstrate that BR and GA influence growth and development by coordinately regulating the expression of specific groups of genes.


Assuntos
Colestanóis/farmacologia , Perfilação da Expressão Gênica , Genes de Plantas/genética , Giberelinas/farmacologia , Oryza/genética , Reguladores de Crescimento de Plantas/farmacologia , Esteroides Heterocíclicos/farmacologia , Brassinosteroides , Regulação da Expressão Gênica de Plantas/genética , Biblioteca Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , RNA de Plantas/genética , Plântula
19.
Clin Nephrol ; 59(6): 423-8, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12834173

RESUMO

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.


Assuntos
Rim/diagnóstico por imagem , Circulação Renal , Adulto , Meios de Contraste , Dopamina , Feminino , Humanos , Rim/efeitos dos fármacos , Córtex Renal/irrigação sanguínea , Masculino , Circulação Renal/efeitos dos fármacos , Ultrassonografia
20.
Clin Nephrol ; 57(1): 69-73, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11837804

RESUMO

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.


Assuntos
Glomerulonefrite/virologia , Infecções por Parvoviridae , Parvovirus B19 Humano , Adulto , Anemia/etiologia , Artralgia/virologia , Biópsia , Proteínas do Sistema Complemento/deficiência , Eritema/virologia , Dermatoses Faciais/virologia , Feminino , Glomerulonefrite/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Infecções por Parvoviridae/imunologia
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