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1.
Front Cardiovasc Med ; 10: 1203130, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465450

RESUMO

Background: Hypertension is a major risk factor for the global burden of disease, and nutrition is associated with an increased risk of mortality from multiple diseases. Few studies have explored the association of nutritional risk with all-cause mortality and cardiovascular mortality in hypertension, and our study aims to fill this knowledge gap. Method: We included data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2016 on a total of 10,037 elderly patients with hypertension. The nutritional status was evaluated using the Geriatric Nutrition Risk Index (GNRI). Kaplan-Meier survival analysis was performed to analyze the survival rates of different nutritional risk groups. COX proportional risk regression models were used to analyze the predictive effect of GNRI on all-cause mortality and cardiovascular mortality in hypertensive patients. Restricted cubic splines (RCS) were used to explore the nonlinear relationship between GNRI and mortality. Result: The mean age of the hypertensive patients was 70.7 years. A total of 4255 (42.3%) all-cause mortality and 1207 (17.2%) cardiovascular mortality occurred during a median follow-up period of 106 months. Kaplan-Meier showed a more significant reduction in survival for the moderate to severe malnutrition risk of GNRI. The adjusted COX proportional hazards model showed that the hazard ratios for all-cause mortality and cardiovascular mortality in the moderate to severe malnutrition risk group for GNRI were 2.112 (95% CI, 1.377,3.240) and 2.604 (95% CI, 1.603,4.229), respectively. The RCS showed that increased GNRI was associated with a reduced risk of all-cause mortality and cardiovascular mortality risk reduction. Conclusion: Malnutrition exposure assessed by GNRI effectively predicts the risk of all-cause mortality and cardiovascular mortality in the elderly with hypertension.

2.
Mar Environ Res ; 188: 106000, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37121173

RESUMO

Organic and Elemental Carbon (OEC) is widely applied in the atmospheric sciences for determining carbon content and distinguishing black carbon contents of aerosols, with an advantage that OEC-based approach can provide thermograms derived from carbonaceous material. It is potential to adopt the advantage to measure the content and composition of organic carbon (OC)% in marine sediments. Here, we utilized the OEC analyzer to measure the OC% in marine sediment based on the pyrolytic oxidation principle, and obtain the OC-derived carbon dioxide (CO2) thermograms. We examined marine sediments and reference materials to understand the stability and reproducibility of OC% measurements using our approach. The findings indicate that the OC% results (ranging from 1.44 to 1.59%, ave. 1.55 ± 0.03%, n = 64) based on this approach are accurate. In addition, CO2 concentration thermograms obtained by repeated measurements exhibit a strong reproducibility. Our approach can thus provide the concentrations of thermally-evolved CO2 with increasing heating temperature to deeply understand the reactivities of OC and the compositions in sediments. We suggest that the OEC-based OC% measurement is credible when samples preparation is well-performed (e.g., suitable sample mass and uniformly distributed loading). To sum up, we provide a means to accurately determine the OC% in marine sediments in terms of the ramped-pyrolysis principle.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Reprodutibilidade dos Testes , Dióxido de Carbono , Monitoramento Ambiental/métodos , Sedimentos Geológicos
3.
Environ Sci Pollut Res Int ; 29(46): 70591-70607, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36114958

RESUMO

Mattress is among the main products of ectopic fermentation system (EFS); however, the research on the data of antimicrobial residues in the mattress of EFS and risk assessments of mattress have not been conducted. This study involved a scale survey to assess the levels and distributions of 54 antimicrobial residues, including 4 tetracyclines, 19 quinolones, 22 sulfonamides, 3 amphenicols, and 6 macrolides in mattress on 12 swine farms that use ectopic fermentation systems (EFS) in Zhejiang Province. A total of 25 antimicrobials were detected in mattress, and the total residue amount of antimicrobial in mattress samples of each farm was 0.77-28.2 g/T. Chlortetracycline had the highest contribution rate, and the residue amount of antimicrobial in mattress is not entirely determined by the start-up time of EFS but is related to the use of feed containing antimicrobial, medication habits, the level of mattress management, and maintenance methods of EFS. The risk assessments of antimicrobial in the mattress were carried out. The results show that the risk of using mattress of EFS for soil is low.


Assuntos
Anti-Infecciosos , Clortetraciclina , Quinolonas , Animais , Antibacterianos , Cloranfenicol , Fazendas , Fermentação , Macrolídeos , Medição de Risco , Solo , Sulfonamidas , Suínos , Tetraciclinas
5.
Ultrasonics ; 54(6): 1419-24, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24746478

RESUMO

Phospholipid encapsulated microbubbles are widely employed as clinical diagnostic ultrasound contrast agents in the 1-5 MHz range, and are increasingly employed at higher ultrasound transmit frequencies. The stiffness and viscosity of the encapsulating "shells" have been shown to play a central role in determining both the linear and nonlinear response of microbubbles to ultrasound. At lower frequencies, recent studies have suggested that shell properties can be frequency dependent. At present, there is only limited knowledge of how the viscoelastic properties of phospholipid shells scale at higher frequencies. In this study, four batches of in-house phospholipid encapsulated microbubbles were fabricated with decreasing volume-weighted mean diameters of 3.20, 2.07, 1.82 and 1.61 µm. Attenuation experiments were conducted in order to assess the frequency-dependent response of each batch, resulting in resonant peaks in response at 4.2, 8.9, 12.6 and 19.5 MHz, respectively. With knowledge of the size measurements, the attenuation spectra were then fitted with a standard linearized bubble model in order to estimate the microbubble shell stiffness Sp and shell viscosity Sf, resulting in a slight increase in Sp (1.53-1.76 N/m) and a substantial decrease in Sf (0.29×10(-6)-0.08×10(-6) kg/s) with increasing frequency. These results performed on a single phospholipid agent show that frequency dependent shell properties persist at high frequencies (up to 19.5MHz).


Assuntos
Materiais Revestidos Biocompatíveis , Meios de Contraste/química , Microbolhas , Fosfolipídeos/química , Ultrassonografia , Materiais Revestidos Biocompatíveis/química , Modelos Teóricos , Reologia , Substâncias Viscoelásticas/química
6.
Ultrasound Med Biol ; 38(7): 1298-305, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22502892

RESUMO

Definity™ is a widely available clinically approved ultrasound contrast agent. The manufacturer's instructions indicate that the refrigerated vial should be allowed to reach room temperature prior to its 45 s mechanical agitation activation process. Activation results in vial heating and it has been previously observed that "smaller" bubbles are formed later in this process (>10 s) when the vial temperature is elevated. The objective of this work was to examine the effects of preactivation vial temperature on the size distribution, frequency dependent attenuation (1.5-27 MHz) and nonlinear imaging performance of Definity™. Experiments were conducted with vials at refrigerator temperature (2°C), room temperature (22°C) or 37°C at the outset of the activation procedure. The size distributions were found to be strongly dependent on preactivation vial temperature and the attenuation results indicated considerable differences in the frequency response of the agent, most notably the appearance of a peak at 4 MHz for the 2°C case. Nonlinear imaging results performed using a 1-5 MHz transducer probe with a wall-less vessel phantom indicated that 2°C vials produced a signal enhancement 5.1 dB greater than for 22°C Definity™ (p < 0.05). These results, therefore, indicate that not permitting the vial to reach room temperature has a considerable impact on the imaging performance of Definity™. Conversely, activating a cooled vial can provide a means by which to improve contrast enhancement when using low frequency clinical transducers.


Assuntos
Meios de Contraste/química , Meios de Contraste/efeitos da radiação , Embalagem de Medicamentos , Fluorocarbonos/química , Fluorocarbonos/efeitos da radiação , Estabilidade de Medicamentos , Ondas de Choque de Alta Energia , Teste de Materiais , Doses de Radiação , Manejo de Espécimes/métodos , Temperatura
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