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1.
ACS Appl Mater Interfaces ; 16(15): 18459-18473, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578815

RESUMO

Reactive oxygen species (ROS)-involved photodynamic therapy (PDT) and chemodynamic therapy (CDT) hold great promise for tumor treatment. However, hypoxia, insufficient H2O2, and overexpressed glutathione (GSH) in the tumor microenvironment (TME) hinder ROS generation significantly. Herein, we reported CaO2@Cu-TCPP/CUR with O2/H2O2/Ca2+ self-supply and GSH depletion for enhanced PDT/CDT and Ca2+ overload synergistic therapy. CaO2 nanospheres were first prepared and used as templates for guiding the coordination between the carboxyl of tetra-(4-carboxyphenyl)porphine (TCPP) and Cu2+ ions as hollow CaO2@Cu-TCPP, which facilitated GSH-activated TCPP-based PDT and Cu+-mediated CDT. The hollow structure was then loaded with curcumin (CUR) to form CaO2@Cu-TCPP/CUR composites. Cu-TCPP prevented degradation of CaO2, while Cu2+ ions reacted with GSH to deplete GSH, produce Cu+ ions, and release TCPP, CaO2, and CUR. CaO2 reacted with H2O to generate O2, H2O2, and Ca2+ to achieve O2/H2O2/Ca2+ self-supply for TCPP-based PDT, Cu+-mediated CDT, and CUR-enhanced Ca2+ overload therapy. Thus, this multilevel ROS amplifier enhances synergistic therapy with fewer side effects and drug resistance.


Assuntos
Curcumina , Nanosferas , Neoplasias , Fotoquimioterapia , Humanos , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Glutationa , Microambiente Tumoral , Linhagem Celular Tumoral , Oxigênio
2.
Huan Jing Ke Xue ; 45(2): 732-743, 2024 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-38471913

RESUMO

The launch of the national carbon emissions trading market in China is a policy to carry out the Beautiful China initiative and to establish a low-carbon economic development system that promotes carbon emission and waste reduction. In order to detect the carbon metabolic processes of the pilot and nonpilot municipalities or provinces in the northern region of China, the theory of urban carbon metabolism and the methods of input-output analysis and ecological network analysis were introduced and used. The results showed that the direct carbon emissions of Beijing and Tianjin had decreased, but their embodied carbon emissions had increased since 2012. The direct and embodied carbon emissions of the pilot sectors in Beijing and Tianjin had the same trend; specifically, the emissions of the sectors of mining and washing of coal, extraction of petroleum and natural gas, and manufacture of non-metallic mineral products decreased significantly, but the sectors of production and supply of electric power and steam with high carbon emission increased. The same trend of the embodied carbon emission intensities of sectors with that of their embodied carbon emissions verified that the embodied added values were not growing with the promotion of the carbon emission trading market. Subsequently, the embodied carbon emission of the pilot sectors in all the municipalities and provinces of the northern region were all contributed mainly by the emissions embodied by a path length less than 6; therefore, it showed that more attention should be paid to the trade among sectors with a path length less than 6 and reducing their carbon emissions. Furthermore, from 2007 to 2012, products or service trading among sectors mostly concentrated on sectors within one municipality or province, and these products or services had the characteristics of low carbon emission. Since 2012, the integration development of the Beijing-Tianjin-Hebei urban agglomeration and the new regional economic patterns established in the northern region both promoted the trading across provinces and across sectors. This research is based on the background of the carbon emission trading policy and aims to build a methodology to identify the key actors and paths in a metabolic system. This could provide a scientific basis for regional policy implementation and regional long-term sustainable development.

3.
J Environ Manage ; 345: 118665, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37579603

RESUMO

Influenced by the interplay of global climate change and urbanization, urban plants have become increasingly homogenized in China. However, regional effects of biotic homogenization cannot be clearly explained due to the lack of continuous large-scale data. Thus, we explored the characteristics and regional effects of biotic homogenization, which not only contributes to the improvement of urban biodiversity, but also has important value for human well-being. Here, we analyzed the woody plants of 101 cities in 8 major urban agglomerations in China. The diversity patterns and influencing factors were explored using generalized additive, geographically weighted regression, and structural equation models. The main results were as follows: (1) The issue of woody plant homogenization is primarily manifested in urban greening species in China. (2) The characteristics of woody plant homogenization exhibit notable regional effects at a large scale. (3) Latitude, urban area, altitude and climatic factors all impact the woody plant homogenization. Thus, we found that the homogenization characteristics of urban greening species exhibit regional variations, influenced by both natural and anthropogenic factors. Finally, we suggested that urban biodiversity management should be considered specific regional environmental, both to meet the needs of residents.


Assuntos
Biodiversidade , Urbanização , Humanos , Cidades , Madeira , Plantas , China , Ecossistema
4.
Saudi Med J ; 44(3): 253-259, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36940973

RESUMO

OBJECTIVES: To examined the efficacy and safety of Peng's Shengjing recipe in treating asthenospermia with deficiency and failure of kidney yang. The traditional Chinese medicine (TCM) Peng's Shengjing recipe might have benefits in treating male asthenospermia. METHODS: This randomized, positive drug-controlled, single-blind pilot study enrolled outpatients from the Third Department of Traditional Chinese Medicine Surgery, Shanghai University of Traditional Chinese Medicine, Shanghai, China, between April 2020 and September 2020. A total of 99 participants were randomized to Shengjing recipe (n=50) and Xuanju capsule (n=49). They were treated for 12 weeks. The primary endpoint was routine semen examinations, including the percentage of sperm motility rated grade A, A+B, and A+B+C, and the clinical effective rate. The secondary endpoints were the levels of gonadotropins. RESULTS: The A grade sperms (18.9% versus [vs.] 13.9%, p=0.030) and A+B grade sperms (42.9% vs. 32.7%, p<0.001) were higher in the Shengjing recipe group than the Xuanju capsule group. The effective rates were 68% and 53.1% in the Shengjing recipe and Xuanju capsule groups (p=0.128). No safety signals were observed. CONCLUSION: Peng's Shengjing recipe improves the quality of sperms and is effective in treating clinical asthenospermia of deficiency of kidney yang. The treatment was well tolerated, without obvious hepatorenal toxicity.Chinese Clinical Research Registry No.: ChiCTR2000030845.


Assuntos
Medicamentos de Ervas Chinesas , Deficiência da Energia Yang , Masculino , Humanos , Projetos Piloto , Deficiência da Energia Yang/complicações , Deficiência da Energia Yang/tratamento farmacológico , Método Simples-Cego , Motilidade dos Espermatozoides , China , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Rim
5.
Opt Express ; 29(14): 22240-22251, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265993

RESUMO

We propose a compression-coding-based surface measurement method that combines single-pixel imaging and heterodyne interference using an optical frequency comb. The real and imaginary parts of the heterodyne interference signals are used to obtain the depth information rapidly. By optimizing the ordering of the Hadamard measurement basis, we reconstruct a three-step sample with heights of approximately 10, 20, and 30 µm without an iterative operation in 6 ms, with a precision of 5 nm. Compared with the uncompressed measurement, the sampling times reduced to 20%, and the measurement time reduced by five times without measurement accuracy loss. The proposed method is effective for rapid measurements, particularly for objects with a simple surface topography.

6.
Phys Rev E ; 103(3-1): 033104, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33862812

RESUMO

Acousotophoretic particle separations in counterpropagating surface acoustic wave (SAW) fields, e.g., standing SAWs (SSAWs), phase modulated SSAWs, tilted angle SSAWs, and partial standing SAWs, have proven successful. But there still lacks analytical tools for predicting the particle trajectory and optimizing the device designs. Here, we study the acoustophoresis of spherical Rayleigh particles in counterpropagating SAW fields and find that particle motions can be characterized into two distinct modes, the drift mode and the locked mode. Through theoretical studies, we provide analytical expressions of particle trajectories in different fields and different moving patterns. Based on these, we obtain theory-based protocols for designing such SAW acoustofluidic particle separation chips, which are demonstrated through finite-element simulations. The results here provide theoretical guidelines for designing high throughput and high efficiency particle separation devices.

7.
Opt Express ; 28(15): 22946-22961, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32752547

RESUMO

We present a femtosecond laser-based interferometry for step-structure surface measurement with a large field of view. A height axial scanning range of 348 µm is achieved by using the method of repetition frequency scanning with reference to the Rb atomic clock and the optical path length difference design for 21 times of the pulse interval. A combined method, which includes the envelope peak positioning method for rough measurement, synthetic-wavelength interferometry for connection, and carrier wave interferometry for fine measurement, is proposed to reconstruct the surface. A three-step specimen with heights of approximately 20, 50, and 70 µm was successfully measured with a height precision of 7 nm, and the accuracy was verified by a commercial white light interferometer. The diameter of the field of view that was demonstrated was 17.3 mm, which could be much larger owing to the high spatial coherence of the femtosecond laser. The results show that the femtosecond laser system combines the step-structure measurement performance of white light interferometry and the high-precision large-field performance of phase shifting interferometry, indicating its potential for widespread use in ultra-precision manufacturing of micro/nano-devices, such as semiconductor chips, integrated circuits, and micro-electro-mechanical systems.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32454860

RESUMO

OBJECTIVE: To evaluate the effectiveness and safety of acupuncture treatment for dysphagia as a complication of stroke. Methods and Design. This is a multicenter, pragmatic, nonrandomized, self-controlled clinical trial. A total of 39 patients were recruited from several Chinese medicine outpatient clinics and hospital-affiliated speech therapy outpatient clinics in Hong Kong. 26 patients completed all the 24 sessions of acupuncture treatment within two months, and only 12 of them were used as self-control. For the self-control group, the retrospective clinical data was taken from the electronic patient records with patient consent. The descriptive swallowing function data were converted into the quantitative Royal Brisbane Hospital Outcome Measure for Swallowing (RBHOMS) scores by two registered speech therapists through a validation process. And the data were validated by reaching consensus between the two speech therapists. All subjects underwent a baseline assessment before commencement of treatment, and outcome assessments were conducted upon the completion of treatment. The primary outcome measure is the RBHOMS score, which is a swallowing disability rating scale for monitoring difficulties in daily swallowing function. Secondary outcome measures include the Chinese version of the Swallow Quality-of-Life Questionnaire and adverse events. All the primary and secondary outcomes were assessed at baseline as well as at the end of acupuncture treatment (month 2). RESULTS: A total of 39 participants aged 46 to 89 years were enrolled in the study, and the male-to-female ratio was 15 : 11. The mean baseline RBHOMS score of all 39 participants was 5.92 ± 2.23. The mean retrospective RBHOMS score of the 12 subjects who were used as self-control was 5.67 ± 1.72 before enrollment, while the mean RBHOMS score of the 26 participants who completed all the 24 sessions of treatment was 6.92 ± 2.07. There were statistically significant differences between the RBHOMS score at the completion of treatment and baseline (p=0.006), and retrospective data (p=0.042). Moreover, a significant difference was also found in terms of swallow quality-of-life score before and after acupuncture treatment (p < 0.01). CONCLUSIONS: This pilot study provides preliminary evidence for the effectiveness of acupuncture for poststroke dysphagia. The findings from this trial can be used as a foundation for future full-scale randomized controlled clinical trials to assess the efficacy and safety of acupuncture for poststroke dysphagia. Ethics and Dissemination. The ethical approval of the clinical research study was granted by the Research Ethics Committee of both New Territories East and West Cluster of Hong Kong. Written informed consent was obtained from all participants, and the study was undertaken according to the ICH-GCP Guidelines. Trial Registration. This trial is registered with ChiCTR-TRC-12002621 and the registration date is 2012-10-26.

9.
Lab Chip ; 19(16): 2728-2740, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31292597

RESUMO

In modelling acoustofluidic chips actuated by surface acoustic waves (SAWs) and using polydimethylsilane (PDMS) as a channel material, reduced models are often adopted to describe the acoustic behaviors of PDMS. Here, based on a standing SAW (SSAW) acoustophoresis chip, we compared three different descriptions of a PDMS chamber and looked into in-chamber physical fields and ensuing particle motion processes through finite element (FE) simulations. Specifically, the PDMS domain was considered as an elastic solid material, a non-flow fluid, and a lossy wall, respectively. The major findings include: (a) the shear waves that propagated in a solid PDMS wall did not influence the in-chamber pressure and ARF fields severely, but induced an observable difference in the acoustic streaming (AS) patterns, and distinctly changed the trajectories of polystyrene particles, especially those whose radii were below 1.5 µm; and (b) the equivalent damping coefficients were linearly dependent on the SAW frequency, characterized by a fixed loss per wavelength, indicating the wave leakage at the interface being the main source of the transmission loss of SAWs. Meanwhile, the acoustic radiation force (ARF) can be overestimated when describing PDMS as a lossy wall, especially at the bottom corners of the chamber, which could cause inaccurate predictions of the motion of big particles. Based on the damping mechanism, a rough protocol is provided for scaling of pressure fields between different models. Some suggestions for device designs and operations are also given based on the obtained findings.

10.
Ultrason Sonochem ; 49: 111-117, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30057178

RESUMO

High intensity focused ultrasound (HIFU) has been regarded as a promising technology for treating cancer and other severe diseases noninvasively. In the present study, dual modality magnetic ultrasound contrast agent microbubbles (MBs) were synthesized by loading the super paramagnetic iron oxide nanoparticles (SPIOs) into the albumin-shelled MBs (referred as SPIO-albumin MBs). Then, both experimental measurements and numerical simulations were performed to evaluate the ability of SPIO-albumin MBs of enhancing HIFU-induced thermal effect. The results indicated that, comparing with regular albumin-shelled MBs, the SPIO-albumin MBs would lead to quicker temperature elevation rate and higher peak temperature. This phenomenon could be explained by the changes in MBs' physical and thermal properties induced by the integration of SPIOs into MB shell materials. In addition, more experimental results demonstrated that the enhancement effect on HIFU-induced temperature elevation could be further strengthened with more SPIOs combined with albumin-shell MBs. These observations suggested that more violent cavitation behaviors might be activated by ultrasound exposures with the presence of SPIOs, which in turn amplified ultrasound-stimulated thermal effect. Based on the present studies, it is reasonable to expect that, with the help of properly designed dual-modality magnetic MBs, the efficiency of HIFU-induced thermal effect could be further improved to achieve better therapeutic outcomes.


Assuntos
Meios de Contraste/química , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Fenômenos Magnéticos , Microbolhas , Temperatura , Albuminas/química , Compostos Férricos/química , Nanopartículas/química
11.
Opt Express ; 26(5): 5747-5757, 2018 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-29529776

RESUMO

We present an absolute distance measurement system using a phase-stable dual-comb system with 56.09 MHz repetition rate and 2 kHz repetition rate difference. A relative phase stability of 0.1 rad in 0.5 ms between two combs is achieved using a mutual locking scheme. The dual-comb ranging system combines the time-of-flight (TOF) method, synthetic-wavelength interferometry (SWI), and carrier wave interferometry (CWI). Each method provides a particular ambiguity range and resolution, and they can be applied simultaneously and linked to enhance the precision and measurement rate of the ranging system. The experimental results demonstrate that a precision of 1.2 µm is obtained without time averaging, and the precision can be improved to 3 nm with only 10 ms averaging time using the SWI method described in this study. The precision reaches a sub-nanometer when the averaging time exceeds 0.1 s. A system with high accuracy and short averaging time would enhance fast measurement performance in various industrial applications. The ambiguity range is about 2.67 m in our system, we test the performance of the system with 1.5 mm range at 1.5 m distance.

12.
Ultrason Sonochem ; 39: 863-871, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28733016

RESUMO

Sonoporation has been widely accepted as a significant tool for gene delivery as well as some bio-effects like hemolysis, bringing in high demands of looking into its underlying mechanism. A two-dimensional (2D) boundary element method (BEM) model was developed to investigate microbubble-cell interaction, especially the morphological and mechanical characteristics around the close-to-bubble point (CP) on cell membrane. Based on time evolution analysis of sonoporation, detailed information was extracted from the model for analysis, including volume expansion ratio of the bubble, areal expansion ratio of the cell, jet velocity and CP displacement. Parametric studies were carried out, revealing the influence of different ultrasound parameters (i.e., driving frequency and acoustic pressure) and geometrical configurations (i.e., bubble-cell distance and initial bubble radius). This model could become a powerful tool not only for understanding bubble-cell interactions, but also for optimizing the strategy of sonoporation, such that it could be safer and of higher efficiency for biological and medical studies especially in clinics.


Assuntos
Células/citologia , Microbolhas , Modelos Biológicos , Sonicação , Membrana Celular/metabolismo
13.
Huan Jing Ke Xue ; 37(3): 1089-97, 2016 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-27337905

RESUMO

A heterotrophic nitrification--aerobic denitrification bacterium named y3 was isolated from the sludge of Jiaozhou Bay using the enrichment medium with seawater as the matrix. It was identified as Pseudomonas sp. based on the morphological observation, physiological experiments and sequence analysis of 16S rRNA. The experiment results showed that the optimal carbon resource was sodium citrate, the optimal pH was 7.0, and the optimal C/N was 13. The strain could use NH4Cl, NaNO2 and KNO3 as sole nitrogen source, and the removal efficiencies were 98.69%, 78.38% and 72.95% within 20 hours, respectively. There was no nitrate and nitrite accumulation during the heterotrophic nitrification process. Within 20 hours, the nitrogen removal efficiencies were 99.56%, 99.75% and 99.41%, respectively, in the mixed system with NO3⁻-N: NO²â»-N of 2:1, 1:1 and 1:2. When the NH4⁺-N: NO3⁻-N ratios were 2: 1 , 1: 1 , 1: 2, the nitrogen removal efficiencies were all 100% . When the NH4⁺-N:NO2⁻-N ratios were 2:1,1:1,1:2, the nitrogen removal efficiencies were 90.43%, 92.79% and 99.96%, respectively. They were higher than those with single nitrogen source. As a result, strain y3 had good nitrogen removal performance in high saline wastewater treatment.


Assuntos
Desnitrificação , Nitrificação , Nitrogênio/química , Pseudomonas/metabolismo , Baías , Processos Heterotróficos , Nitratos/química , Nitritos/química , Pseudomonas/classificação , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Esgotos/química , Esgotos/microbiologia , Águas Residuárias/química
14.
World J Gastroenterol ; 4(5): 426-429, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11819337

RESUMO

AIM:To investigate whether the arcuate nucleus (ARC) could modulate gastric motility, and if so, what are the mechanisms or pathways.METHODS:Wistar rats, anaesthetized with urethan, parameters of stimulation and electrolytic lesion sites were determined according to the Paxinos and Watson ATLAS of rat brain in steriotaxic coordinate. Intragastric pressure (IGP) and gastric motility were measured by Reybould's method.RESULTS:Electrical stimulation of ARC could obviously decrease the IGP by 42.2% plus minus 5.4%, n =15,P < 0.01, and the phasic gastric contractions disappeared.The analysis showed that the locus coeruleus (LC) and dorsal raphe (DR) nuclei may be involved in central,but without the invovement of alpha-endorphinergic neurons rich in the ARC, while in periphery, the peripheral neural pathways are both vagus and sympathetic nerves.The fibers in vagus may be non-cholinergic. Humoral factors may also be involved.At the receptor level, Tonic action of adrenergic nerve in the stomach is mainly inhibitory;alpha-receptors, which may be present on the stomach wall and mediate inhibition; and -alpha-receptors, which come into play through vagus, mediate inhibition, but those present on the smooth muscle mediate sympathetic excitation.Microinjection of TRH into ARC could significantly increase the IGP by 183.02% (0.53kPa plus minus 0.08kPa vs 1.5k Pa plus minus 0.6kPa, n =10,P < 0.001), the rate and amplitude of phasic gastric contraction were also increased (3cpm vs 6cpm-8cpm). The peripheral pathway of such excitatory effects were transmitted with cholinergic vagus nerve mediated by M-receptor.CONCLUSION:ARC could modulate gastric motility biphasically, inhibitory and excitatory, depending on the nature of stimuli.

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