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1.
Epidemiol Infect ; 148: e94, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374248

RESUMO

Coronavirus disease 2019 (COVID-19) patients were classified into four clinical stages (uncomplicated illness, mild, severe and critical pneumonia) depending on disease severity. We aim to investigate the corresponding clinical, radiological and laboratory characteristics between different clinical stages. A retrospective, single-centre study of 101 confirmed patients with COVID-19 at Renmin Hospital of Wuhan University from 2 January to 28 January 2020 was enrolled; follow-up endpoint was on 8 February 2020. Clinical data were collected and compared during the course of illness. The median age of the 101 patients was 51.0 years and 33.6% were medical staff. Fever (68%), cough (50%) and fatigue (23%) are the most common symptoms. About 26% patients underwent the mechanical ventilation and 98% patients were treated with antibiotics. Thirty-seven per cent patients were cured and 11 died. On admission, the number of patients with uncomplicated illness, mild, severe and critical pneumonia were 2 [2%], 86 [85%], 11 [11%] and 2 [2%]. Forty-four of the 86 mild pneumonia progressed to severe illness within 4 days, with nine patients worsened due to critical pneumonia within 4 days. Two of the 11 severe patients improved to mild condition while three others deteriorated. Significant differences were observed among groups of different clinical stages in numbers of influenced pulmonary segments (6 vs. 12 vs. 17, P < 0.001). A significantly upward trend was witnessed in ground-glass opacities overlapped with striped shadows (33% vs. 42% vs. 55% vs. 80%, P < 0.001), while pure ground-glass opacities gradually decreased as disease progressed (45% vs. 35% vs. 24% vs. 13%, P < 0.001) within 12 days. Lymphocytes, prealbumin and albumin showed a downtrend as disease progressed from mild to severe or critical condition, an uptrend was found in white blood cells, C-reactive protein, neutrophils and lactate dehydrogenase. The proportions of serum amyloid A > 300 mg/l in mild, severe and critical conditions were 18%, 46% and 71%, respectively.


Assuntos
Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Adulto , COVID-19 , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia , Prognóstico , Índice de Gravidade de Doença
3.
Environ Sci Technol ; 46(17): 9793-801, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22831707

RESUMO

With years of full-scale experience for precombustion CO(2) capture, amine-based technologies are emerging as the prime contender for postcombustion CO(2) capture. However, concerns for postcombustion applications have focused on the possible contamination of air or drinking water supplies downwind by potentially carcinogenic N-nitrosamines and N-nitramines released following their formation by NO(x) reactions with amines within the capture unit. Analytical methods for N-nitrosamines in drinking waters were adapted to measure specific N-nitrosamines and N-nitramines and total N-nitrosamines in solvent and washwater samples. The high levels of amines, aldehydes, and nitrite in these samples presented a risk for the artifactual formation of N-nitrosamines during sample storage or analysis. Application of a 30-fold molar excess of sulfamic acid to nitrite at pH 2 destroyed nitrite with no significant risk of artifactual nitrosation of amines. Analysis of aqueous morpholine solutions purged with different gas-phase NO and NO(2) concentrations indicated that N-nitrosamine formation generally exceeds N-nitramine formation. The total N-nitrosamine formation rate was at least an order of magnitude higher for the secondary amine piperazine (PZ) than for the primary amines 2-amino-2-methyl-1-propanol (AMP) and monoethanolamine (MEA) and the tertiary amine methyldiethanolamine (MDEA). Analysis of pilot washwater samples indicated a 59 µM total N-nitrosamine concentration for a system operated with a 25% AMP/15% PZ solvent, but only 0.73 µM for a 35% MEA solvent. Unfortunately, a greater fraction of the total N-nitrosamine signal was uncharacterized for the MEA-associated washwater. At a 0.73 µM total N-nitrosamine concentration, a ~25000-fold reduction in concentration is needed between washwater units and downwind drinking water supplies to meet proposed permit limits.


Assuntos
Aminas/química , Compostos de Anilina/análise , Sequestro de Carbono , Nitrobenzenos/análise , Óxidos de Nitrogênio/química , Nitrosaminas/análise , Poluentes Químicos da Água/análise , Dióxido de Carbono/isolamento & purificação , Ácidos Sulfônicos/química , Abastecimento de Água
4.
Environ Sci Technol ; 46(21): 12079-87, 2012 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-23030462

RESUMO

Ferrate [Fe(VI); FeO(4)(2-)] is an emerging oxidizing agent capable of controlling chemical and microbial water contaminants. Here, inactivation of MS2 coliphage by Fe(VI) was examined. The inactivation kinetics observed in individual batch experiments was well described by a Chick-Watson model with first-order dependences on disinfectant and infective phage concentrations. The inactivation rate constant k(i) at a Fe(VI) dose of 1.23 mgFe/L (pH 7.0, 25 °C) was 2.27(±0.05) L/(mgFe × min), corresponding to 99.99% inactivation at a Ct of ~4 (mgFe × min)/L. Measured k(i) values were found to increase with increasing applied Fe(VI) dose (0.56-2.24 mgFe/L), increasing temperature (5-30 °C), and decreasing pH conditions (pH 6-11). The Fe(VI) dose effect suggested that an unidentified Fe byproduct also contributed to inactivation. Temperature dependence was characterized by an activation energy of 39(±6) kJ mol(-1), and k(i) increased >50-fold when pH decreased from 11 to 6. The pH effect was quantitatively described by parallel reactions with HFeO(4)(-) and FeO(4)(2-). Mass spectrometry and qRT-PCR analyses demonstrated that both capsid protein and genome damage increased with the extent of inactivation, suggesting that both may contribute to phage inactivation. Capsid protein damage, localized in the two regions containing oxidant-sensitive cysteine residues, and protein cleavage in one of the two regions may facilitate genome damage by increasing Fe(VI) access to the interior of the virion.


Assuntos
Desinfetantes/farmacologia , Compostos de Ferro/farmacologia , Levivirus/efeitos dos fármacos , Compostos de Potássio/farmacologia , Purificação da Água/métodos , Proteínas do Capsídeo/metabolismo , Escherichia coli/virologia , Genoma Viral/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Cinética , Levivirus/fisiologia , Modelos Biológicos , Temperatura , Inativação de Vírus/efeitos dos fármacos , Poluentes da Água
5.
Front Aging Neurosci ; 14: 833287, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35462702

RESUMO

Background and Purpose: Freezing of gait (FOG) is a common gait disturbance phenomenon in multiple system atrophy (MSA) patients. The current investigation assessed the incidence FOG in a cross-sectional clinical study, and clinical correlations associated with it. Methods: Ninety-nine MSA patients from three hospitals in China were consecutively enrolled in the study. Eight patients were subsequently excluded from the analysis due to incomplete information. The prevalence of FOG symptoms in the MSA cohort was determined, and clinical manifestations in MSA patients with and without FOG were assessed. Results: Of 91 MSA patients, 60 (65.93%) exhibited FOG. The incidence of FOG increased with disease duration and motor severity and was correlated with modified Hoehn and Yahr (H-Y) stages [odds ratio (OR), 0.54; 95% confidence interval (CI), 0.33-3.92], longer disease duration (OR, 0.54, 95% CI, 0.37-0.78), higher Unified Multiple System Atrophy Rating Scale (UMSARS) score (OR, 0.96, 95% CI, 0.93-0.99), MSA-cerebellum subtype (OR, 2.99, 95% CI, 1.22-7.33), levodopa-equivalent dose (LDED) (OR, 0.998, 95% CI, 0.997-1.00), and higher Scale for the Assessment and Rating of Ataxia (SARA) score (OR, 0.80, 95% CI, 0.72-0.89) (logistic regression). Motor dysfunction was significantly positively associated with lower quality of life scores (p < 0.01). Conclusion: FOG is a common symptom in MSA patients and it is correlated with poor quality of life, disease progression and severity, levodopa-equivalent dose, and cerebellum impairment.

6.
Environ Sci Technol ; 45(11): 4793-801, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21542626

RESUMO

Large quantities of antimicrobial agents used in livestock production are released to soils by land application of manure, but only limited information is available on mechanisms that contribute to antimicrobial fate in soils under variable biogeochemical conditions. Dissipation of the sulfonamide antimicrobial sulfamethoxazole was examined in soil microcosms incubated under different terminal electron-accepting conditions (aerobic, nitrate-reducing, Fe(III)-reducing, and sulfate-reducing). Somewhat unexpectedly, sulfamethoxazole dissipation was fastest under Fe(III)-reducing conditions, with concentrations decreasing by >95% within 1 day. The rapid transformation was attributed to abiotic reactions between sulfamethoxazole and Fe(II) generated by microbial reduction of Fe(III) soil minerals. Separate experiments demonstrated that sulfamethoxazole was abiotically transformed in Fe(II)-amended aqueous suspensions of goethite (α-FeOOH((s))), and observed rate constants varied with the extent of Fe(II) sorption to goethite. Sulfamethoxazole transformation is initiated by a 1-electron reductive cleavage of the N-O bond in the isoxazole ring substituent, and observed products are consistent with Fe(II)-mediated reduction and isomerization processes. These findings reveal potentially important, but previously unrecognized, pathways that may contribute to the fate of sulfamethoxazole and related chemicals in reducing soil environments.


Assuntos
Anti-Infecciosos/metabolismo , Compostos de Ferro/química , Microbiologia do Solo , Poluentes do Solo/metabolismo , Sulfametoxazol/metabolismo , Anti-Infecciosos/química , Biodegradação Ambiental , Biotransformação , Compostos de Ferro/metabolismo , Oxirredução , Poluentes do Solo/química , Sulfametoxazol/química
7.
Environ Sci Technol ; 45(8): 3635-42, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21417319

RESUMO

Recent work demonstrates that three widely administered antibiotics (ciprofloxacin, lincomycin, and trimethoprim) are oxidized by potassium permanganate [KMnO(4), Mn(VII)] under conditions relevant to water treatment operations. However, tests show that little to no mineralization occurs during reactions with Mn(VII), so studies were undertaken to characterize the reaction products and pathways and to assess the effects of Mn(VII)-mediated transformations on the antibacterial activity of solutions. Several oxidation products were identified for each antibiotic by liquid chromatography-tandem mass spectrometry (LC-MS/MS). For ciprofloxacin, 12 products were identified, consistent with oxidation of the tertiary aromatic and secondary aliphatic amine groups on the piperazine ring and the cyclopropyl group. For lincomycin, seven products were identified that indicate structural changes to the pyrrolidine ring and thioether group. For trimethoprim, seven products were identified, consistent with Mn(VII) reaction at C═C double bonds on the pyrimidine ring and the bridging methylene group. Oxidation pathways are proposed based on the identified products. Bacterial growth inhibition bioassays (E. coli DH5α) show that the mixture of products resulting from Mn(VII) reactions with the antibiotics collectively retain negligible antibacterial potency in comparison to the parent antibiotics. These results suggest that permanganate can be an effective reagent for eliminating the pharmaceutical activity of selected micropollutants during drinking water treatment.


Assuntos
Antibacterianos/química , Permanganato de Potássio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Antibacterianos/análise , Antibacterianos/toxicidade , Bioensaio , Ciprofloxacina/análise , Ciprofloxacina/química , Escherichia coli/efeitos dos fármacos , Lincomicina/química , Manganês/química , Oxirredução , Trimetoprima/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Abastecimento de Água/análise
8.
Environ Sci Technol ; 44(16): 6416-22, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20704243

RESUMO

The ubiquitous occurrence of antibiotics in aquatic environments raises concerns about potential adverse effects on aquatic ecology and human health, including the promotion of increased antibiotic resistance. This study examined the oxidation of three widely detected antibiotics (ciprofloxacin, lincomycin, and trimethoprim) by potassium permanganate [KMnO(4); Mn(VII)]. Reaction kinetics were described by second-order rate laws, with apparent second-order rate constants (k(2)) at pH 7 and 25 degrees C in the order of 0.61 +/- 0.02 M(-1) s(-1) (ciprofloxacin) < 1.6 +/- 0.1 M(-1) s(-1) (trimethoprim) < 3.6 +/- 0.1 M(-1) s(-1) (lincomycin). Arrhenius temperature dependence was observed with apparent activation energies (E(a)) ranging from 49 kJ mol(-1) (trimethoprim) to 68 kJ mol(-1) (lincomycin). Rates of lincomycin and trimethoprim oxidation exhibited marked pH dependences, whereas pH had only a small effect on rates of ciprofloxacin oxidation. The effects of pH were quantitatively described by considering parallel reactions between KMnO(4) and individual acid-base species of the target antibiotics. Predictions from a kinetic model that included temperature, KMnO(4) dosage, pH, and source water oxidant demand as input parameters agreed reasonably well with measurements of trimethoprim and lincomycin oxidation in six drinking water utility sources. Although Mn(VII) reactivity with the antibiotics was lower than that reported for ozone and free chlorine, its high selectivity and stability suggests a promising oxidant for treating sensitive micropollutants in organic-rich matrices (e.g., wastewater).


Assuntos
Antibacterianos/química , Permanganato de Potássio/química , Purificação da Água/métodos , Água/química , Ciprofloxacina/química , Concentração de Íons de Hidrogênio , Cinética , Lincomicina/química , Manganês/química , Modelos Químicos , Oxirredução , Temperatura , Trimetoprima/química , Abastecimento de Água
9.
Front Neurol ; 10: 1068, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781013

RESUMO

Objective: To explore the correlation between diabetic cognitive impairment (DCI) and diabetic retinopathy (DR) through examining the cognitive function and the metabolism of the cerebrum in Type 2 diabetes mellitus (T2DM) by 1H-MRS. Methods: Fifty-three patients with T2DM were enrolled for this study. According to the fundus examination, the patients were divided into the DR group (n = 26) and the T2DM without DR group (T2DM group, n = 27). Thirty healthy adults were selected as a control group (HC group, n = 30). Cognitive function was measured by Montreal Cognitive Assessment (MoCA). The peak areas of N-acetylaspartate (NAA), Cho-line (Cho), Creatine (Cr), and Myo-inositol (mI) as well as their ratios were detected by proton magnetic resonance spectroscopy (1H-MRS). The difference analysis between the three groups was performed by one-way ANOVA. When p < 0.05, LSD-t was applied. A partial correlation analysis (with age as a covariate) was used to analyze the correlation between metabolites in the DR group and MoCA scores. Among all T2DM patients, Chi-square test age, gender, education level, BMI, SBP, DBP, FPG, HbA1c, TC, TG, HDL-C, LDL-C, DR, and DCI correlation were measured. Differences were statistically significant while P < 0.05. Results: 1. The scores of MoCA in the DR group or in the T2DM group were significantly less than those in the HC group (F = 3.54, P < 0.05), and the scores of MoCA in the DR group were significantly less than those in the other groups (F = 3.61, P < 0.05). 2. There were significant differences for NAA in the bilateral hippocampus in DR patients, T2DM patients, and healthy controls (P < 0.05). 3. The NAA/Cr was significantly positively correlated with the score of MoCA in DR patients' left hippocampus (r = 0.781, P < 0.01). 4. Chi-square analysis found that there was a correlation between DR and DCI (x 2 = 4.6, df = 1, p = 0.032, plt: 0.05). There was no correlation between other influencing factors and DCI (P > 0.05). Conclusion: DCI is closely correlated with the DR in patients with T2DM. Hippocampal brain metabolism may have some changes in two sides of NAA in patients with DR, 1H-MRS may provide effective imaging strategies and methods for the early diagnosis of brain damage and quantitative assessment cognitive function in T2DM.

10.
Water Res ; 41(12): 2612-26, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17433403

RESUMO

The widespread detection of pharmaceutically active compounds, including many synthetic antimicrobial agents, in aquatic environments is raising public health concerns. As a result, there is growing interest in the development of innovative technologies to efficiently transform these compounds to non-toxic and pharmaceutically inactive byproducts. This work examines the photocatalytic degradation of sulfamethoxazole (SMX) and related sulfonamide antimicrobial agents in aqueous suspensions of nanophase titanium dioxide (TiO(2)). Experimental results demonstrate that SMX is mineralized by TiO(2) irradiated with ultraviolet-A light (UVA: 324<

Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/efeitos da radiação , Sulfonamidas/química , Sulfonamidas/efeitos da radiação , Poluentes Químicos da Água/química , Poluentes Químicos da Água/efeitos da radiação , Catálise , Oxirredução , Fotoquímica , Titânio/química , Raios Ultravioleta , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
11.
Sci Total Environ ; 387(1-3): 54-67, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17822745

RESUMO

The critical load concept has become widely accepted as an important theoretical basis for establishing effective acid deposition control strategies. In the critical load calculations, the influence of variation in base cation (BC) deposition, which plays an important role in mitigating acidification, was seldom considered. In this manner, high uncertainty and over-estimation might be caused in those areas where current BC deposition is very high and of significant anthropogenic origin since anthropogenic deposition can change due to human activity. In this study, an extended sulfur(S)-nitrogen (N)-BC function based on the Steady State Mass Balance (SSMB) method is applied to calculate the critical loads for five sampled catchments in southern China under variable S, N, and BC deposition. The ceiling of S deposition (when N deposition is zero; CL(max)(S)) under current BC deposition varies from 4.5 to 10.8 keq ha(-1) yr(-1) among the five catchments, and the ceiling of N deposition (when S deposition is zero; CL(max)(N)) varies from 23.2 to 54.5 keq ha(-1) yr(-1). A 75% reduction in BC deposition is estimated to cause a 46%-86% decrease of CL(max)(S) and 45%-81% decrease of CL(max)(N). The critical loads for acidification are not exceeded in any of the five catchments under the current base cation deposition, despite extremely high S deposition in some places. However, if the BC deposition decreases to 25% of current while S remains unchanged, critical loads will be exceeded at all sites except one. A sensitivity analysis confirms that the long-term future BC deposition is among the most important parameters to the uncertainty of critical load, together with the dose-response relationship between ecosystem health and soil solution chemistry.


Assuntos
Poluentes Atmosféricos/análise , Nitrogênio/análise , Enxofre/análise , Árvores , Chuva Ácida , Cátions/análise , China , Metais/análise , Modelos Teóricos
12.
Environ Sci Technol ; 43(2): 509-15, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19238987

RESUMO

Experimental studies were conducted to examine the oxidation of carbamazepine, an anticonvulsant drug widely detected in surface waters and sewage treatment effluent, by potassium salts of permanganate (Mn(VII); KMnO4) and ferrate (Fe(VI); K2FeO4). Results show that both Mn(VII) and Fe(VI) rapidly oxidize carbamazepine by electrophilic attack at an olefinic group in the central heterocyclic ring, leading to ring-opening and a series of organic oxidation products. Reaction kinetics follow a generalized second-order rate law, with apparent rate constants at pH 7.0 and 25 degrees C of 3.0 (+/-0.3) x 10(2) M(-1) s(-1) for Mn(VII) and 70(+/-3) M(-1) s(-1) for Fe(VI). Mn(VII) reaction rates exhibit no pH dependence, whereas Fe(VI) reaction rates increase dramatically with decreasing pH, due to changing acid-base speciation of Fe(VI). Further studies with Mn(VII) show that most common nontarget water constituents, including natural organic matter, have no significant effect on rates of carbamazepine oxidation; reduced metals and (bi)sulfide exert a stoichiometric Mn(VII) demand that can be incorporated into the kinetic model. The removal of carbamazepine in two utility source waters treated with KMnO4 agrees closely with predictions from the kinetic model that was parametrized using experiments conducted in deionized water at much higher reagent concentrations.


Assuntos
Carbamazepina/química , Ferro/química , Manganês/química , Cromatografia Líquida , Cinética , Espectrometria de Massas , Modelos Químicos , Oxirredução , Água
13.
Environ Sci Technol ; 41(6): 1815-20, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17410769

RESUMO

Base cations (BC) play an important role to prevent soil acidification. In certain acid sensitive areas, such as China, BC deposition is high and a considerable fraction is of anthropogenic origin. BC deposition might decrease in the future with the implementation of air pollution control measures. The effect of changes in BC deposition, however, has seldom been considered in critical load calculations based on the steady-state mass balance (SSMB) method. In order to better quantify the importance of the BC deposition for acid deposition mitigation policy, an extension of the SSMB method for critical load calculation for soil acidification is presented. The BC deposition is taken into account as a variable along with sulfur (S) and nitrogen (N) deposition, creating an S-N-BC critical load function. As a case study, critical loads of S and N for the Tie Shan Ping catchment in Chongqing in southwest China under variable BC deposition were calculated. Results indicate that abatement of BC deposition has significant impact on the critical loads of S and N. A 75% reduction in BC of assumed anthropogenic origin decreases the critical loads of acids by 58%. The current deposition does not exceed the critical loads, but if BC deposition from anthropogenic sources was controlled, then the exceedance would be considerable. Uncertainty analysis show that the size of the BC deposition of natural origin is the single parameter contributing the most to the steady-state S and N critical load. The extended critical load function can be used by policy makers to set more reasonable acidity control strategies in the future. The method also highlights for policymakers the "competition" between emission control of particulate matter driven by human health targets and potential increase of net acid load from such measures.


Assuntos
Ácidos/análise , Cátions/química , Poluição Ambiental/prevenção & controle , Nitrogênio/química , Poluentes do Solo/análise , Enxofre/química , China , Modelos Teóricos , Política Pública
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