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1.
Photochem Photobiol Sci ; 21(5): 659-665, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34755326

RESUMEN

This brief article reports on the fabrication of a prototype novel semiconductor digital device, a microwave-discharge light-emitting diode (MDLED), consisting of an LED and a Schottky barrier diode encapsulated in a quartz ampoule. Coating the surface of this ampoule with TiO2 yielded a new photocatalytic TiO2 unit (MDLED-TiO2) for use in treating contaminated wastewaters. To the extent that this MDLED-TiO2 is driven only by microwave energy, there is no need for electric wires or electrical AC power. As much of the activity of TiO2 photocatalyst is enhanced and ultraviolet light emission is generated only by irradiating with microwaves, the MDLED-TiO2 affords a simple water treatment device as demonstrated in the present study. The digital device consisted of 14 pieces of MDLED-TiO2  units immersed into a model contaminated wastewater toward the decomposition of organic pollutants and sterilization of natural bacteria-contaminated wastewaters performed in an energy-saving manner simply by irradiating the wastewaters with microwaves.


Asunto(s)
Rayos Ultravioleta , Aguas Residuales , Catálisis , Microondas , Titanio/química
2.
Photochem Photobiol Sci ; 21(10): 1819-1831, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35781788

RESUMEN

This study examines the microwave chemical risks posed by photocatalysts present in sunscreens (physical filters) against the increasing use of microwaves (radio waves) in the environment, sometimes referred to as electronic smog. Specifically, the study assesses the damage caused by silica-coated physical filters (photocatalysts, TiO2⋅ and/or ZnO) contained in commercially available sunscreens and fresh silica-coated ZnO for sunscreens to mouse skin fibroblasts cells (NIH/3T3) evaluated in vitro by the life/death of cells using two types of electromagnetic waves: UV light and microwave radiation, and under simultaneous irradiation with both UV light and microwaves. Conditions of the electromagnetic waves were such as to be of lower light irradiance than that of UVA/UVB radiation from incident sunlight, and with microwaves near the threshold power levels that affect human health. The photocatalytic activity of the physical filters was investigated by examining the degradation of the rhodamine B (RhB) dye in aqueous media and by the damage caused to DNA plasmids from E. coli. Compared to the photocatalytic activity of ZnO and TiO2 when irradiated with UV light alone, a clear enhanced photocatalytic activity was confirmed upon irradiating these physical filters concurrently with UV and microwaves. Moreover, the uptake of these metal oxides into the NIH/3T3 cells led to the death of these cells as a result of the enhanced photocatalytic activity of the metal oxides on exposure to microwave radiation.


Asunto(s)
Nanopartículas , Óxido de Zinc , Ratones , Animales , Humanos , Protectores Solares/farmacología , Microondas , Escherichia coli , Esmog , Rayos Ultravioleta , Dióxido de Silicio
3.
Chemistry ; 27(37): 9466-9481, 2021 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-33877732

RESUMEN

A number of synthetic methodologies and applications of carbon quantum dots (CQDs) have been reported since they were first discovered nearly two decades ago. Unlike metal-based or semiconductor-based (e. g., metal chalcogenides) quantum dots (MSQDs), CQDs have the unique feature of being prepared through a variety of synthetic protocols, which are typically understood from considerations of reaction models and photoluminescence mechanisms. Consequently, this brief review article describes quantum dots, in general, and CQDs, in particular, from various viewpoints: (i) their definition, (ii) their photophysical properties, and (iii) the superiority of CQDs over MSQDs. Where possible, comparisons are made between CQDs and MSQDs. First, however, the review begins with a general brief description of quantum dots (QDs) as nanomaterials (sizes≤10 nm), followed by a short description of MSQDs and CQDs. Described subsequently are the various top-down and bottom-up approaches to synthesize CQDs followed by their distinctive photophysical properties (emission spectra; quantum yields, Φs).

4.
Photochem Photobiol Sci ; 20(1): 101-111, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33721240

RESUMEN

Mercury lamps are typically the major light sources in water treatments. However, the use of mercury has raised some concerns with regard to the Minamata Convention on Mercury. As such, Hg-free microwave discharged electrodeless lamps (MDELs) that incorporate a rare gas and a halogen gas (R/H-MDEL) have been investigated with such Hg-free mixture filler gases as Kr/Cl2, Xe/Cl2, and Kr/Br2 (R/H). Of these, only the Kr/Br2-MDEL lamp is self-ignited at an inner pressure of 15 Torr when irradiated with microwave radiation. Accordingly, a novel Kr/Br2 three-layer MDEL (Kr/Br2-MDEL) photoreactor was fabricated to assess the optimal gas composition and gas pressure toward its performance vis-à-vis the treatment of model wastewaters contaminated with the tartrazine dye in aqueous media and with Escherichia coli (E. coli) bacteria. The extent of degradation of the tartrazine dye and sterilization of E. coli increased with irradiation time, with microwave radiation power (100, 200, and 300 W), and with increased sample flow rate 0.4 L min‒1 to 0.8 L min‒1. The tartrazine-contaminated wastewater was treated at a flow rate of 0.4 L min‒1 for 60 min of microwave irradiation by three different protocols that resulted in UV (62%) >> UV/ROS (24%) > ROS (0%); ROS denotes reactive oxygen species. After 5 min irradiation of the E.coli wastewater, also at 0.4 L min‒1, the order was UV (99.5%) ≈ UV/ROS (99.3%) >> ROS (14.5%). For comparison, the photosterilization of E. coli with an equivalent Hg/Ar-MDEL light source was also nearly complete (99.7%). Thus, the suitability of the environmentally friendlier Kr/Br2 gas fill to replace Hg/Ar filler gas in MDELs for the photoelimination of organic pollutants and microbial disinfection in aqueous media has been demonstrated.

5.
Molecules ; 26(8)2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33924444

RESUMEN

This study used controlled microwaves to elucidate the response of adhesive components to microwaves and examined the advantages of microwave radiation in curing epoxy adhesives. Curing of adhesives with microwaves proceeded very rapidly, even though each component of the adhesive was not efficiently heated by the microwaves. The reason the adhesive cured rapidly is that microwave heating was enhanced by the electrically charged (ionic) intermediates produced by the curing reaction. In contrast, the cured adhesive displayed lower microwave absorption and lower heating efficiency, suggesting that the cured adhesive stopped heating even if it continued to be exposed to microwaves. This is a definite advantage in the curing of adhesives with microwaves, as, for example, adhesives dropped onto polystyrene could be cured using microwave heating without degrading the polystyrene base substrate.

6.
Chem Rec ; 19(1): 118-139, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30277645

RESUMEN

Several studies have used microwaves as a heat source for carrying out various types of reactions employing circulation reaction vessels. The microwave flow chemical synthesis methodology is most appropriate in the use of microwaves in chemical syntheses. It can attenuate the problem of microwave heating (non-uniform heating and penetration depth) and maximize the benefits (rapid heating and first temperature adjustments). In this brief review, we examine and explain some of the relevant features of microwave heating with applicative examples of the usage of microwave flow chemistry equipment in carrying out organic syntheses, enzymatic reactions, and (not least) nanoparticle syntheses.


Asunto(s)
Fenómenos Químicos , Enzimas/química , Nanopartículas del Metal/química , Microondas , Compuestos Orgánicos/síntesis química , Oro/química , Calor , Microscopía Electrónica de Transmisión , Espectrofotometría Ultravioleta
7.
Photochem Photobiol Sci ; 18(2): 328-335, 2019 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-30467574

RESUMEN

Constraints on light sources that use mercury (arc lamps) are evolving with the establishment of the Minamata Convention, which has led to the proliferation of LEDs. However, no LED light source emits intense ultraviolet radiation at wavelengths below 300 nm for photolytic applications. Thus, it is necessary to develop suitable UV light sources for the decontamination of wastewater and water sterilization processing. Herein, we explore various substitute gases (e.g., N2, Ar, He and SF6) to replace mercury, which is commonly employed in arc lamps, using an EL (electroluminescence) quartz assembly platform similar to microwave-discharge electrodeless lamps. Although nitrogen is an inexpensive and safe gas, it cannot generate significant UV radiation in the UVC region of 200-300 nm. This problem in the Hg-free light source was resolved by mixing a very small quantity of sulfur hexafluoride (SF6) as an additive filler gas in a nitrogen-, argon- or helium-filled assembly. The low-pressure mercury lamp consisting of Hg/Ar filler gases is ca. 25% more efficient than the novel N2/SF6 lamp toward the photolytic decomposition of Rhodamine-B (RhB) dye-contaminated wastewater (1.66 × 10-4 mM min-1versus 1.22 × 10-4 mM min-1). Nonetheless, the latter has proven far more efficient than an LED source emitting 365 nm radiation (0.057 × 10-4 mM min-1). The addition of TiO2 to RhB-contaminated wastewater demonstrated that this Hg-free N2/SF6 light source is as efficient as the corresponding Hg/Ar electroluminescent lamp toward the photocatalytic decomposition of the RhB dye pollutant.

8.
Clin Exp Nephrol ; 23(1): 16-25, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30367317

RESUMEN

Histological classification is essential in the clinical management of immunoglobulin A nephropathy (IgAN). However, there are limitations in predicting the prognosis of IgAN based on histological information alone, which suggests the need for better prognostic models. Therefore, we defined a prognostic model by combining the grade of clinical severity with the histological grading system by the following processes. We included 270 patients and explored the clinical variables associated with progression to end-stage renal disease (ESRD). Then, we created a predictive clinical grading system and defined the risk grades for dialysis induction by a combination of the clinical grade (CG) and the histological grade (HG). A logistic regression analysis revealed that the 24-h urinary protein excretion (UPE) and the estimated glomerular filtration rate (eGFR) were significant independent variables. We selected UPE of 0.5 g/day and eGFR of 60 ml/min/1.73 m2 as the threshold values for the classification of CG. The risk of progression to ESRD of patients with CG II and III was significantly higher than that of patients with CG I. The patients were then re-classified into nine compartments based on the combination of CG and HG. Furthermore, the nine compartments were grouped into four risk groups. The risk of ESRD in the moderate, high, and super-high-risk groups was significantly higher than that in the low-risk group. Herein, we are giving a detailed description of our grading system for IgA nephropathy that predicted the risk of dialysis based on the combination of CG and HG.


Asunto(s)
Diálisis , Glomerulonefritis por IGA/diagnóstico , Progresión de la Enfermedad , Glomerulonefritis por IGA/patología , Glomerulonefritis por IGA/terapia , Humanos , Pruebas de Función Renal , Medición de Riesgo
9.
Acta Med Okayama ; 72(5): 535-538, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30369613

RESUMEN

Some patients with chronic kidney disease (CKD) receiving hemodialysis develop erythropoietin-resistant anemia, possibly due to zinc deficiency. The frequency of zinc deficiency in CKD (stages 1-5 and 5D) and CKD improvement via zinc supplementation are not completely verified. Here 500 CKD patients (Stage 1/2, n=100; Stage 3, n=100; Stage 4, n=100, Stage n=5, 100; Stage 5D, n=100) will be recruited to determine the frequency of serum zinc deficiency at each CKD stage. Patients with serum zinc concentrations <80 µg/dL will be treated with zinc acetate dihydrate (NobelzinR) to evaluate its effects on hypozincemia, taste disturbances, and anemia.


Asunto(s)
Anemia/tratamiento farmacológico , Insuficiencia Renal Crónica/complicaciones , Trastornos del Gusto/tratamiento farmacológico , Acetato de Zinc/uso terapéutico , Zinc/deficiencia , Adulto , Anciano , Estudios Transversales , Humanos , Persona de Mediana Edad , Insuficiencia Renal Crónica/sangre , Adulto Joven , Zinc/sangre
10.
Clin Exp Nephrol ; 21(6): 1068-1074, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28389814

RESUMEN

BACKGROUND: High circulating levels of soluble tumor necrosis factor receptors (TNFRs: TNFR1, TNFR2) predict renal function decline in a variety of kidney diseases. Tonsillectomy with steroid pulse (TSP) therapy has been reported as a remission induction therapy in IgA nephropathy (IgAN), mainly in Japan. However, little is known about whether TNFR levels change after TSP therapy in patients with IgAN. METHODS: Two hundred twenty-three patients with IgAN were stratified according to the estimated glomerular filtration rate (eGFR): Group I (eGFR ≥ 60 mL/min/1.73 m2, n = 172) and Group II (eGFR < 60 mL/min/1.73 m2, n = 51). We measured serum TNFR levels with immunoassay in all patients at the time of renal biopsy, and also in patients whose samples just before the first (after tonsillectomy) (n = 34) and/or the third steroid pulse therapy (n = 77) were available. RESULTS: The TNFR levels were significantly higher in Group II than in Group I. A significant negative correlation was observed between TNFR levels and eGFR at baseline (TNFRs: r > -0.50). In multivariate logistic regression analysis, both TNFRs were associated with renal function decline, independent of age and uric acid levels. Proteinuria and hematuria remarkably improved after TSP therapy, as expected. In comparison with baseline TNFR levels, the levels of TNFR2, but not TNFR1, decreased significantly just before the third steroid pulse therapy, although both levels did not change after tonsillectomy. CONCLUSIONS: The TNFR2 level did not change after tonsillectomy alone but decreased significantly after steroid pulse therapy in patients with IgAN.


Asunto(s)
Glomerulonefritis por IGA/sangre , Glucocorticoides/administración & dosificación , Metilprednisolona/administración & dosificación , Receptores Tipo II del Factor de Necrosis Tumoral/sangre , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Tonsilectomía , Adulto , Femenino , Glomerulonefritis por IGA/tratamiento farmacológico , Glomerulonefritis por IGA/cirugía , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Blood Purif ; 44(1): 24-29, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28237983

RESUMEN

BACKGROUND/AIMS: This study was aimed at evaluating the effect of cardiac function with postoperative arteriovenous fistula (AVF) blood flow in hemodialysis (HD) patients. METHODS: A total of 45 HD patients were examined at the Juntendo University Hospital. The AVF blood flow was measured using ultrasonography, and the cardiac function was measured using echocardiography. Correlation between these parameters and the rate of change in body weight (BW) was analyzed. RESULTS: The number of postoperative days significantly correlated with the AVF blood flow, and it positively correlated with the stroke volume (SV). The postoperative AVF blood flow in patients with reduced ejection fraction (EF) was lower than that in patients with normal EF. The rate of change of BW negatively correlated with that of SV, positively correlated with cardiac output (CO), and positively correlated with CO in patients with an AVF blood flow of more than 1,000 mL/min. CONCLUSION: It appears that the cardiac function can be improved by controlling the BW even in patients with high AVF blood flow.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Gasto Cardíaco/fisiología , Diálisis Renal/métodos , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Peso Corporal , Femenino , Humanos , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Diálisis Renal/efectos adversos , Estudios Retrospectivos , Volumen Sistólico
12.
Photochem Photobiol Sci ; 15(8): 1061-70, 2016 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-27444263

RESUMEN

To date syntheses of nitrogen-doped TiO2 photocatalysts (TiO2-xNx) have been carried out under high temperatures and high pressures with either NH3 or urea as the nitrogen sources. This article reports for the first time the facile preparation of N-doped TiO2 (P25 titania) in aqueous media at ambient temperature and pressure under inert conditions (Ar- and N2-purged dispersions) with 4-nitrophenol (or 4-nitrobenzaldehyde) as the nitrogen source. The resulting N-doped P25 TiO2 materials were characterized by UV/Vis and X-ray photoelectron spectroscopies (XPS) that confirmed the presence of nitrogen within the photocatalyst; X-ray diffraction (XRD) techniques confirmed the crystalline phases of the doped material. The photocatalytic activity of N-doped TiO2 was assessed through examining the photodegradation of 4-chlorophenol in aqueous media and iso-propanol as a volatile pollutant under UV/Vis and visible-light irradiation. Under visible light irradiation, undoped P25 was inactive contrary to N-doped P25 that successfully degraded 95% of the 4-chlorophenol (after 10 h) and 23% of iso-propanol (after 2.5 h).

13.
Clin Exp Nephrol ; 20(5): 740-747, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26707759

RESUMEN

BACKGROUND: It has been reported that echocardiographic parameters are independently associated with the progression to dialysis in patients with chronic kidney disease (CKD) (stages 3-5). The objective of the present study was to evaluate whether physical, biochemical, and echocardiographic parameters are associated with the progression to dialysis in early CKD (stage 1-3) patients. METHODS: This retrospective study enrolled 272 CKD patients who underwent echocardiography at the time of diet education, renal biopsy, and the examination of kidney injuries at Juntendo University Hospital, Tokyo, Japan, from 2001 to 2010. All of these CKD patients were classified into stages 1-3. The study patients received regular follow-up at our outpatient clinic in our division. The renal end point was defined as commencement of dialysis. RESULTS: Patients with progression to dialysis were significantly associated with higher levels of left ventricular mass index (LVMI), urinary protein, systolic blood pressure, many kinds of anti-hypertensive drugs, and lower levels of albumin and hemoglobin. In a Cox proportional hazard regression analysis, LVMI [hazard ration (HR) 1.018; 95 % confidence interval (CI) 1.007-1.029; p = 0.002], urinary protein and hemoglobin were independently associated with factors for progression to dialysis in early CKD patients. CONCLUSION: This study of patients in early CKD demonstrated that higher LVMI and urinary protein and that lower levels of hemoglobin in blood were associated with progression to dialysis. LVMI evaluated by echocardiography may identify a high risk of progression to dialysis in early CKD patients.


Asunto(s)
Hipertrofia Ventricular Izquierda/complicaciones , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Adulto , Anciano , Antihipertensivos/uso terapéutico , Biomarcadores/sangre , Biopsia , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Quimioterapia Combinada , Ecocardiografía , Femenino , Hemoglobinas/metabolismo , Hospitales Universitarios , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Proteinuria/etiología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/diagnóstico , Estudios Retrospectivos , Factores de Riesgo , Albúmina Sérica/metabolismo , Albúmina Sérica Humana , Factores de Tiempo , Tokio
14.
Molecules ; 21(12)2016 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-27916848

RESUMEN

This article evokes the futuristic visions of two giants, one a writer, Jules Verne, who foresaw water as the coal of the future, and the other a scientist, Giacomo Ciamician, who foresaw the utilization of solar energy as an energy source with which to drive photochemical and photocatalytic reactions for the betterment of mankind. Specifically, we examine briefly the early work of the 1960s and 1970s on the photosplitting of free water and water adsorbed on solid supports, based mostly on metal oxides, from which both hydrogen and oxygen evolve in the expected stoichiometric ratio of 2 to 1. The two oil crises of the 1970s (1973 and 1979) spurred the interest of researchers from various disciplines (photochemistry, photo-catalysis and photoelectrochemistry) in search of a Holy Grail photocatalyst, process, or strategy to achieve efficient water splitting so as to provide an energy source alternative to fossil fuels. Some approaches to the photosplitting of water adsorbed on solid insulators (high bandgap materials; Ebg ≥ 5 eV) and semiconductor photocatalysts (metal oxides) are described from which we deduce that metal oxides with bandgap energies around 5 eV (e.g., ZrO2) are more promising materials to achieve significant water splitting on the basis of quantum yields than narrower bandgap photocatalysts (e.g., TiO2; Ebg ≈ 3.0-3.2 eV), which tend to be relatively inactive by comparison. Although proof of concept of the photosplitting of water has been demonstrated repeatedly in the last four decades, much remains to be done to find the Holy Grail photocatalyst and/or strategy to achieve significant yields of hydrogen.


Asunto(s)
Procesos Fotoquímicos , Energía Solar , Agua/química , Catálisis , Hidrógeno/química , Metales/química , Oxígeno/química
15.
Biochem Biophys Res Commun ; 467(3): 549-55, 2015 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-26435502

RESUMEN

Rac1, a GTPase of the Rho subfamily, has a crucial role in cytoskeletal architecture, as well as the regulation of cell migration and growth. However, renal injury in mice with podocyte-specific deletion of Rac1 has yet to be elucidated fully due to conflicting findings. Herein, we identified a possible role for Rac1 in podocytes of streptozotocin- (STZ) induced diabetic mice. The urinary albumin/creatinine ratio (ACR) in the knockout (KO) group was significantly higher than that in the wild type (WT) group at any week of age. A more marked ACR increase was observed in STZ/KO group than STZ/WT group, although ACR did increase with weeks of age in both diabetic groups. The kidney sections from diabetic mice revealed a glomerular hypertrophy with mesangial expansion, but there was no appreciable difference in glomerular findings under a light microscope between STZ/WT and STZ/KO mice. However, an electron microscopy analysis revealed that regardless of the presence or absence of diabetes, both KO (KO and STZ/KO) groups had a higher rate of foot process effacement compared with both WT (WT and STZ/WT) groups. The expression levels of the slit diaphragm protein, podocin, was reduced with the induction of diabetes, and the levels in the STZ/KO group experienced a further reduction compared with the STZ/WT group. The number of WT1-positive cells in the STZ/KO group was more significantly decreased than that in the other three groups. In contrast, the numbers of cleaved caspase 3- and TUNEL-positive cells in the glomeruli of the STZ/KO group were more increased than those in the STZ/WT group. Thus, this study provides evidence that podocyte-specific deletion of Rac1 results in morphological alteration in podocytes, and that the induction of apoptosis or decreased expression of the slit diaphragm proteins by hyperglycemic stimuli are associated with the progression of diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/patología , Eliminación de Gen , Neuropéptidos/fisiología , Podocitos/metabolismo , Proteína de Unión al GTP rac1/fisiología , Animales , Nefropatías Diabéticas/metabolismo , Mesangio Glomerular/patología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Neuropéptidos/genética , Neuropéptidos/metabolismo , Estreptozocina , Proteína de Unión al GTP rac1/genética , Proteína de Unión al GTP rac1/metabolismo
16.
Photochem Photobiol Sci ; 14(12): 2187-94, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26456244

RESUMEN

This article reports on the fabrication and enhanced performance of a novel microwave discharge electrodeless lamp (MDEL) consisting of a three layered cylindrical structure that was effective in the remediation of wastewater containing the 2,4-D herbicide and the near total sterilization of bacteria-contaminated pond water (E. coli and other microorganisms) through photolysis with the emitted vacuum-UV (185 nm) and UVC (254 nm) light from the MDEL and through chemical oxidation with reactive oxygen species (ROS) produced by the photolysis of dioxygen and air oxygen through one of the photoreactors. The flow rates of the 1.0 L contaminated waters were 0.6 and 1.2 L min(-1). The integrated UV/ROSO2 and UV/ROSair methods used to carry out the degradation of 2,4-D and sterilization processes were more effective than either the UV method alone or the ROSO2 and ROSair methods for short time periods (5 or 8 min). At a lower flow rate, 79% of 2,4-D was degraded by the UV/ROSO2 method and 55% by UV/ROSair after 8 min. At a faster flow rate of 1.2 L min(-1), degradation of 2,4-D in 1.0 L volume of water was 84% and 77% complete by the UV/ROSO2 and the UV/ROSair method, respectively, after 8 min of irradiation. The number of kills of E. coli bacteria was nearly quantitative (98 and 99%) by the UV/ROSO2 and UV/ROSair methods after treating the contaminated water for 5 min. The decrease of total viable microorganisms in pond water was 90% and 80% after 5 min of microwave irradiation at a flow rate of 1.2 L min(-1) by the integrated methods UV/ROSO2 and UV/ROSair, respectively. The rate of flow of oxygen gas through the photoreactor impacted the extent of degradation and the related dynamics of the 2,4-D herbicide.

17.
Nephrology (Carlton) ; 20 Suppl 4: 7-13, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26439537

RESUMEN

AIM: Anaemia is a common complication in patients with chronic kidney disease (CKD), which may initiate or accelerate left ventricular (LV) hypertrophy (LVH). The present study is a retrospective analysis to assess whether anaemia treatment is independently associated with LV remodelling prior to initiation of dialysis in CKD patients. METHODS: Biochemical and physical values were collected over a period of more than 120 days prior to the initiation of dialysis in 27 patients with CKD. The left ventricular mass index (LVMI) was evaluated by echocardiography twice (at the baseline and the follow-up at the initiation of the dialysis period). RESULTS: Patients using long-acting erythropoietin stimulating agents (L-ESA) had the tendency of maintaining higher levels of haemoglobin (Hb) than those using short-acting ESA (S-ESA). Patients using L-ESA showed a more significant improvement in the erythropoietin resistance index (ERI) than those of using S-ESA. In a multivariate regression analysis, the average Hb level for the observational period, the level of Hb at the initiation of dialysis and the use of L-ESA were independently associated factors for the LVMI at the initiation of dialysis. A lower LVMI at the initiation of dialysis and an improvement of the LVMI during the observational period were detected in the highest tertile of average Hb (10.4 g/dL). CONCLUSION: Long-acting ESA was effective and stable when treating anaemia until the start of dialysis. It is important to treat anaemia for the prevention of LV remodelling in CKD patients. These findings have some therapeutic implications for treatment strategies for pre-dialysis patients.


Asunto(s)
Anemia/tratamiento farmacológico , Anemia/etiología , Hematínicos/farmacología , Hematínicos/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Remodelación Ventricular/efectos de los fármacos , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Estudios Retrospectivos , Resultado del Tratamiento
18.
BMC Nephrol ; 16: 27, 2015 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-25885587

RESUMEN

BACKGROUND: The TNF-like weak inducer of apoptosis (TWEAK) contributes to kidney inflammation producing secretion by renal cells. The present study examined whether the level of TWEAK is associated with histologic findings in patients with IgA nephropathy (IgAN). METHODS: The levels of urinary TWEAK (uTWEAK) from 116 IgAN patients, 50 non-IgA kidney disease patients, and 50 healthy individuals were measured by ELISA. Histological findings of renal biopsy specimens of patients with IgAN were evaluated according to the Oxford classification and histological classification for IgAN in Japan. We investigated the expression of TWEAK/Fn14 in renal tissues of those patients and assessed the effect of TWEAK in glomerular mesangial cells and podocytes. RESULTS: The levels of uTWEAK in the patients with IgAN and other renal diseases were significantly higher than in the healthy controls (P < 0.001). In the IgAN patients, the levels of uTWEAK correlated significantly with urinary protein excretion and extracapillary proliferation (r = 0.54, P < 0.001 and r = 0.32, P < 0.001, respectively). In a comparison of the levels of uTWEAK at diagnosis with that of follow-up, the levels of uTWEAK in patients with clinical and partial remission decreased significantly. We showed not only increased expression of both TWEAK and Fn14 in IgAN patients with glomerular crescents but also TWEAK-induced cell motility in podocytes. CONCLUSIONS: The relationship between the levels of uTWEAK and clinicopathological findings observed in this study suggests that TWEAK/Fn14 system affects crescent formation and proteinuria in patients with IgAN.


Asunto(s)
Glomerulonefritis por IGA/patología , Glomerulonefritis por IGA/orina , Receptores del Factor de Necrosis Tumoral/sangre , Factores de Necrosis Tumoral/orina , Adulto , Animales , Apoptosis , Biomarcadores/metabolismo , Biopsia con Aguja , Estudios de Casos y Controles , Células Cultivadas , Citocina TWEAK , Ensayo de Inmunoadsorción Enzimática , Femenino , Tasa de Filtración Glomerular , Humanos , Inmunohistoquímica , Japón , Masculino , Ratones , Persona de Mediana Edad , Podocitos/metabolismo , Valores de Referencia , Sensibilidad y Especificidad , Receptor de TWEAK
19.
J Clin Lab Anal ; 29(5): 353-60, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25131157

RESUMEN

BACKGROUND: The impact of being overweight remains unclear in Asian populations that tend to be lean. The objective of this study is to clarify the impact of body mass index (BMI) and metabolic factors on the prognosis of Japanese patients with IgA nephropathy (IgAN). METHODS: A total of 193 patients with IgAN were divided into three groups equally according to BMI: Group L (lean group, BMI: 15.6-20.1 kg/m(2) ), Group M (middle group, BMI: 20.2-23.0 kg/m(2) ), and Group O (obesity group, BMI: 23.1-31.9 kg/m(2) ). Clinical data at the time of renal biopsy and the progression of the patients after renal biopsy were analyzed. RESULTS: At the time of renal biopsy, hypertension, dyslipidemia, hyperuricemia, and hypercomplementemia in Group O were more significant compared with those in Group L and/or Group M. Uric acid, triglyceride, C3, C4, high-density lipoprotein cholesterol, serum creatinine, systolic blood pressure (BP), and diastolic BP were significantly correlated with BMI. In Group O, the remission of urinary protein over 5 years was significantly delayed using a log-rank test. At the final observation, the BMI of each group was as similar as that at renal biopsy. The patients with aggressive therapy, such as steroid therapy and/or tonsillectomy in Group O did not have major side effects, except for a slight elevation of total cholesterol and low-density lipoprotein cholesterol. CONCLUSION: Even slightly high BMI seems to be a risk factor for progress in Japanese patients with IgAN.


Asunto(s)
Índice de Masa Corporal , Glomerulonefritis por IGA/epidemiología , Glomerulonefritis por IGA/fisiopatología , Adolescente , Adulto , Anciano , Niño , Progresión de la Enfermedad , Femenino , Humanos , Japón/epidemiología , Masculino , Síndrome Metabólico , Persona de Mediana Edad , Obesidad , Adulto Joven
20.
Nephrol Dial Transplant ; 29(2): 289-300, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24081857

RESUMEN

BACKGROUND: The prevention and restoration of peritoneal damage is a critical mission in peritoneal dialysis (PD). Transplantation of mesothelial cells has been suggested to suppress peritoneal injury during PD. Few studies have examined the efficacy and safety of cell transplantation. We evaluated the paracrine effects of mesothelial transplantation during peritoneal repair using immortalized temperature-sensitive mesothelial cells (TSMCs) in chlorhexidine gluconate (CG)-induced peritoneal fibrosis rats. METHODS: Continuous-infusion pumps containing 8% CG were placed into the abdominal cavity for 21 days. After the removal of the pumps, the TSMCs were injected into the peritoneal cavity at Day 22 (Tx-1 group) or 29 (Tx-2 group). Morphological findings and mRNA expressions of regeneration-related factors were examined at Days 22, 29 and 35. RESULTS: Peritoneal thickness was aggravated in the Tx-1 group. Levels of transforming growth factor (TGF)-ß, vascular endothelial growth factor (VEGF) and matrix metalloproteinase-2 mRNA in the Tx-1 group at Day 35 were comparable with those at Day 22. The levels of Snail, B-Raf and ERK-1, markers of epithelial to mesenchymal transition and of the RAS/MAPK pathway in the Tx-1 group, were significantly higher than those in the Tx-2 group. TGF-ß and VEGF were produced from the transplanted mesothelial cells and the surrounding cells in the Tx-1 group. CONCLUSION: It appears that the paracrine effect of transplanted mesothelial cells during peritoneal repair is associated with its surrounding condition. It is important to determine the most appropriate time for developing peritoneal repair through mesothelial transplantation.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Comunicación Paracrina/genética , Fibrosis Peritoneal/terapia , Trasplante de Células Madre , Animales , Antígenos Transformadores de Poliomavirus/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales/citología , Células Epiteliales/trasplante , Transición Epitelial-Mesenquimal , Regulación de la Expresión Génica , Inmunohistoquímica , Fallo Renal Crónico/terapia , Masculino , Diálisis Peritoneal , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/prevención & control , Peritoneo/metabolismo , Peritoneo/patología , ARN/genética , Ratas , Ratas Sprague-Dawley , Ratas Transgénicas , Reacción en Cadena en Tiempo Real de la Polimerasa , Temperatura
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