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1.
World J Hepatol ; 11(6): 522-530, 2019 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-31293720

RESUMEN

BACKGROUND: Liver cirrhosis is the late stage of hepatic fibrosis and is characterized by portal hypertension that can clinically lead to decompensation in the form of ascites, esophageal/gastric varices or encephalopathy. The most common sequelae associated with liver cirrhosis are neurologic and neuropsychiatric impairments labeled as hepatic encephalopathy (HE). Well established triggers for HE include infection, gastrointestinal bleeding, constipation, and medications. Alterations to the gut microbiome is one of the leading ammonia producers in the body, and therefore may make patients more susceptible to HE. AIM: To investigate the relationship between the use of proton pump inhibitors (PPIs) and HE in patients with cirrhosis. METHODS: This is a single center, retrospective analysis. Patients were included in the study with an admitting diagnosis of HE. The degree of HE was determined from subjective and objective portions of hospital admission notes using the West Haven Criteria. The primary outcome of the study was to evaluate the grade of HE in PPI users versus non-users at admission to the hospital and throughout their hospital course. Secondary outcomes included rate of infection, gastrointestinal bleeding within the last 12 mo, mean ammonia level, and model for end-stage liver disease scores at admission. RESULTS: The HE grade at admission using the West Haven Criteria was 2.3 in the PPI group compared to 1.7 in the PPI nonuser group (P = 0.001). The average length of hospital stay in PPI group was 8.3 d compared to 6.5 d in PPI nonusers (P = 0.046). Twenty-seven (31.8%) patients in the PPI user group required an Intensive Care Unit admission during their hospital course compared to 6 in the PPI nonuser group (16.7%) (P = 0.138). Finally, 10 (11.8%) patients in the PPI group expired during their hospital stay compared to 1 in the PPI nonuser group (2.8%) (P = 0.220). CONCLUSION: Chronic PPI use in cirrhotic patients is associated with significantly higher average West Haven Criteria for HE compared to patients that do not use PPIs.

2.
Nanoscale ; 6(17): 10134-9, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-25042514

RESUMEN

We experimentally investigate the protection of electron spin coherence of a nitrogen-vacancy (NV) centre in diamond by dynamic nuclear spin polarization (DNP). The electron spin decoherence of an NV centre is caused by the magnetic field fluctuation of the (13)C nuclear spin bath, which contributes large thermal fluctuation to the centre electron spin when it is in an equilibrium state at room temperature. To address this issue, we continuously transfer the angular momentum from electron spin to nuclear spins, and pump the nuclear spin bath to a polarized state under the Hartmann-Hahn condition. The bath polarization effect is verified by the observation of prolongation of the electron spin coherence time (T). Optimal conditions for the DNP process, including the pumping pulse duration and repeat numbers, are proposed by numerical simulation and confirmed by experiment. We also studied the depolarization effect of laser pulses. Our results provide a new route for quantum information processing and quantum simulation using the polarized nuclear spin bath.

3.
Sci Rep ; 3: 1498, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23511233

RESUMEN

In contrast to the classical world, an unknown quantum state cannot be cloned ideally, as stated by the no-cloning theorem. However, it is expected that approximate or probabilistic quantum cloning will be necessary for different applications, and thus various quantum cloning machines have been designed. Phase quantum cloning is of particular interest because it can be used to attack the Bennett-Brassard 1984 (BB84) states used in quantum key distribution for secure communications. Here, we report the first room-temperature implementation of quantum phase cloning with a controllable phase in a solid-state system: the nitrogen-vacancy centre of a nanodiamond. The phase cloner works well for all qubits located on the equator of the Bloch sphere. The phase is controlled and can be measured with high accuracy, and the experimental results are consistent with theoretical expectations. This experiment provides a basis for phase-controllable quantum information devices.

4.
J Hazard Mater ; 186(1): 849-54, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21146288

RESUMEN

The present study aims at investigating the performance of a vacuum ultraviolet (VUV, 185 nm) and TiO(2) oxidation system for the pretreatment of oily wastewater from restaurant. The influence of irradiation time, pH, dissolved oxygen (DO), the dosage of TiO(2) and the initial chemical oxygen demand (COD) concentration on COD removal efficiency was ascertained and optimum process conditions for stable and effective operation were determined. Under the optimum conditions of irradiation 10 min, initial COD 3981 mg/L, TiO(2) 150 mg/L, pH 7.0 and flow rate of air 40 L/h, the process of VUV and TiO(2)/VUV achieved removal efficiencies of COD, BOD(5) and oil as 50±3%, 37±2%, 86±3%, and 63±3%, 43±2%, 70±3%, respectively. The biodegradability factor f(B) of the wastewater was determined as 1.56 which indicated that the VUV/TiO(2) process improved the biodegradability of the oily wastewater significantly. Results clearly indicate that VUV/TiO(2) photolysis tends to destruct parts of COD, BOD(5), and ammonia, as well as enhances the biodegradability of the oily wastewater simultaneously. Thus, this technique could be used as a pretreatment step for conventional biological treatment of oily wastewater.


Asunto(s)
Restaurantes , Titanio , Rayos Ultravioleta , Catálisis , Fotoquímica , Vacio
5.
Huan Jing Ke Xue ; 29(9): 2618-23, 2008 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19068653

RESUMEN

A bacterial strain that could degrade bromoamine acid (BAA) as the sole carbon source was isolated. It was identified as Sphingomonas sp. based on 16S rRNA gene sequence analysis and physio-biochemical characteristics. Under the optimal growth conditions, with temperature of 30 degrees C, pH of 7.0, rotating rate of 100 r/min and (NH4)2SO4 as the nitrogen source, the decolorization percentage of BAA (100 mg/L) could reach 99% within 14 h. NaCl of low concentration ( < 2%) facilitated the decolorization, while NaCl of higher concentration (> or = 2%) had inhibition effect. The effect of initial BAA concentration on decolorization could be described by the Haldane model, and the optimal specific decolorization rate of 1.4 h(-1) could be obtained when the initial concentration of BAA was 1393.5 mg/L. The strain could not mineralize BAA completely, and 52.4% of the total organic carbon was removed at the end of the reaction. The analysis of metabolites using GC-MS and HPLC-MS showed that phthalic acid was the metabolic intermediate which could be further degraded through 3, 4-dihydroxybenzoic acid route and serve as the growth substrate, and the end product was estimated to be either 2-amino-3-hydroxy-5-bromobenzenesulfonic acid or 2-amino-4-hydroxy-5-bromobenzenesulfonic acid.


Asunto(s)
Antraquinonas/metabolismo , Microbiología del Suelo , Sphingomonas/metabolismo , Biodegradación Ambiental , Eliminación de Residuos Líquidos/métodos
6.
Huan Jing Ke Xue ; 29(2): 488-93, 2008 Feb.
Artículo en Chino | MEDLINE | ID: mdl-18613525

RESUMEN

A quinoline-degrading bacterium QL2, which utilizes quinoline as sole source of carbon, nitrogen and energy, was isolated from activated sludge in a coke-plant wastewater biological treatment system. According to the morphological characteristics, physiological and biochemical characteristics, and sequence analysis of 16S rRNA, the strain was identified as Rhodococcus sp.. The optimal temperature, initial pH, and shaker rotary speed for strain QL2 utilizing quinoline are 35-42 degrees C, pH 8-9, and 150 r/min, respectively. Extra nitrogen sources stimulate the isolate growth on quinoline, and inorganic nitrogen better than organic nitrogen, NH4+ -N better than NO3(-) -N. The degradation reaction of quinoline by strain QL2 can be described with zero order kinetic equation within the initial quinoline concentrations of 60-680 mg/L. When the initial concentration was 150 mg/L, quinoline was degraded completely in 8 hours and TOC removal efficiency was 70% in 14 hours. This bacterium produced pigmented compounds, and ring nitrogen was released into the growth medium as ammonium. The main intermediate in the degradation pathway was 2-hydroxyquinoline by the analysis of HPLC and GC/MS. With a broad range of substrate utilization, the strain can degrade phenol, naphthalene, pyridine, and some other kinds of aromatic compounds.


Asunto(s)
Quinolinas/metabolismo , Rhodococcus/aislamiento & purificación , Rhodococcus/metabolismo , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Filogenia , ARN Ribosómico 16S/genética , Rhodococcus/genética , Aguas del Alcantarillado/microbiología
7.
J Hazard Mater ; 160(2-3): 289-94, 2008 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-18420344

RESUMEN

A novel aerobic gram-positive bacterial strain capable of utilizing quinoline as sole source of carbon, nitrogen and energy was isolated from activated sludge of a coke plant wastewater treatment process. The isolate was identified as Rhodococcus sp. QL2 based on its morphology, physiochemical properties in addition to the results from 16S rDNA sequence analysis. The optimum temperature and the pH for its growth were 35-40 degrees C and 8.0, respectively. Extra nitrogen sources stimulated the bacterial growth on quinoline. Strain QL2 had strong quinoline degradability, and its degradation kinetics could be described with Haldane's model. Strain QL2 also had a broad range of substrate utilization. Identification of intermediates by GC/MS showed Rhodococcus sp. QL2 degraded quinoline via two pathways simultaneously.


Asunto(s)
Quinolinas/química , Rhodococcus/metabolismo , Aguas del Alcantarillado/análisis , Biodegradación Ambiental , Cromatografía Líquida de Alta Presión , Medios de Cultivo , ADN Bacteriano/biosíntesis , ADN Bacteriano/genética , Análisis Factorial , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Cinética , Nitrógeno/química , Fenotipo , Filogenia , Rhodococcus/química , Rhodococcus/crecimiento & desarrollo , Temperatura
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