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1.
Inorg Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012164

RESUMO

Designing high-performance binder-free electrochemical electrodes is crucially important toward supercapacitors. In this paper, a Zn/N-doped porous carbon film coating on flexible carbon nanotubes (ZIF-8@CT-800) derived from the epitaxial Zn-MOF film growth on cotton textile was successfully fabricated via a combination of the liquid-phase epitaxial (LPE) method and calcination treatments. The ZIF-8@CT-800 serves directly as a self-supported electrode for supercapacitors and exhibits a high areal capacitance of 930 mF·cm-2 at a current density of 1 mA·cm-2 and a good recyclability of 86% after 2000 cycles. The excellent supercapacitor property is ascribed to the unique structural design of ZIF-8@CT-800, which provides appropriate channels for enhanced electronic and ionic transport as well as increased surface area for accessing more electrolyte ions. This work will provide significant guidance for designing MOF-derived porous carbon to construct flexible binder-free electrode materials with high electrochemical performance.

2.
Gut Microbes ; 16(1): 2347722, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38706205

RESUMO

The intestine is prone to radiation damage in patients undergoing radiotherapy for pelvic tumors. However, there are currently no effective drugs available for the prevention or treatment of radiation-induced enteropathy (RIE). In this study, we aimed at investigating the impact of indole-3-carboxaldehyde (I3A) derived from the intestinal microbiota on RIE. Intestinal organoids were isolated and cultivated for screening radioprotective tryptophan metabolites. A RIE model was established using 13 Gy whole-abdominal irradiation in male C57BL/6J mice. After oral administration of I3A, its radioprotective ability was assessed through the observation of survival rates, clinical scores, and pathological analysis. Intestinal stem cell survival and changes in the intestinal barrier were observed through immunofluorescence and immunohistochemistry. Subsequently, the radioprotective mechanisms of I3A was investigated through 16S rRNA and transcriptome sequencing, respectively. Finally, human colon cancer cells and organoids were cultured to assess the influence of I3A on tumor radiotherapy. I3A exhibited the most potent radioprotective effect on intestinal organoids. Oral administration of I3A treatment significantly increased the survival rate in irradiated mice, improved clinical and histological scores, mitigated mucosal damage, enhanced the proliferation and differentiation of Lgr5+ intestinal stem cells, and maintained intestinal barrier integrity. Furthermore, I3A enhanced the abundance of probiotics, and activated the AhR/IL-10/Wnt signaling pathway to promote intestinal epithelial proliferation. As a crucial tryptophan metabolite, I3A promotes intestinal epithelial cell proliferation through the AhR/IL-10/Wnt signaling pathway and upregulates the abundance of probiotics to treat RIE. Microbiota-derived I3A demonstrates potential clinical application value for the treatment of RIE.


Assuntos
Microbioma Gastrointestinal , Indóis , Camundongos Endogâmicos C57BL , Probióticos , Receptores de Hidrocarboneto Arílico , Via de Sinalização Wnt , Animais , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Humanos , Probióticos/administração & dosagem , Probióticos/farmacologia , Receptores de Hidrocarboneto Arílico/metabolismo , Indóis/metabolismo , Indóis/farmacologia , Protetores contra Radiação/farmacologia , Organoides/metabolismo , Lesões por Radiação/metabolismo , Lesões por Radiação/prevenção & controle , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Mucosa Intestinal/efeitos da radiação , Intestinos/microbiologia , Intestinos/efeitos da radiação , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética
3.
J Hazard Mater ; 472: 134498, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38733782

RESUMO

Advanced oxidation processes for the treatment of organic pollutants in wastewater suffer from difficulties in mineralization, potential risks of dissolved residues, and high oxidant consumption. In this study, radical-initiated polymerization is dominated in an UV/peroxydisulfate (PDS) process to eliminate organic pollutant of pharmaceutical metoprolol (MTP). Compared with an ideal degradation-based UV/PDS process, the present process can save four fifths of PDS consumption at the same dissolved organic carbon removal of 47.3%. Simultaneously, organic carbon can be recovered from aqueous solution by separating solid polymers at a ratio of 50% of the initial chemical oxygen demand. The chemical structure of products was analyzed to infer the transformation pathways of MTP. Unlike previous studies on simple organic pollutants that the polymerization can occur independently, the polymerization of MTP is dependent on the partial degradation of MTP, and the main monomer in polymerization is a dominant degradation product (4-(2-methoxyethyl)-phenol, denoted as DP151). The separated solid polymers are formed by repeated oxidation and coupling of DP151 or its derivatives through a series of intermediate oligomers. This proof-of-concept study demonstrates the advantage of polymerization-dominated mechanism on dealing with large organic molecules with complex structures, as well as the potential of UV/PDS process for simultaneous organic pollution reduction and organic carbon recovery from aqueous solution.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38485099

RESUMO

PURPOSE: Radiation-induced intestinal injury (RIII) commonly occur during abdominal-pelvic cancer radiation therapy; however, no effective prophylactic or therapeutic agents are available to manage RIII currently. This study aimed to clarify the potential of probiotic consortium supplementation in alleviating RIII. METHODS AND MATERIALS: Male C57BL/6J mice were orally administered a probiotic mixture comprising Bifidobacterium longum BL21, Lactobacillus paracasei LC86, and Lactobacillus plantarum Lp90 for 30 days before exposure to 13 Gy of whole abdominal irradiation. The survival rates, clinical scores, and histologic changes in the intestines of mice were assessed. The impacts of probiotic consortium treatment on intestinal stem cell proliferation, differentiation, and epithelial barrier function; oxidative stress; and inflammatory cytokines were evaluated. A comprehensive examination of the gut microbiota composition was conducted through 16S rRNA sequencing, while changes in metabolites were identified using liquid chromatography-mass spectrometry. RESULTS: The probiotic consortium alleviated RIII, as reflected by increased survival rates, improved clinical scores, and mitigated mucosal injury. The probiotic consortium treatment exhibited enhanced therapeutic effects at the histologic level compared with individual probiotic strains, although there was no corresponding improvement in survival rates and colon length. Moreover, the probiotic consortium stimulated intestinal stem cell proliferation and differentiation, enhanced the integrity of the intestinal epithelial barrier, and regulated redox imbalance and inflammatory responses in irradiated mice. Notably, the treatment induced a restructuring of the gut microbiota composition, particularly enriching short-chain fatty acid-producing bacteria. Metabolomic analysis revealed distinctive metabolic changes associated with the probiotic consortium, including elevated levels of anti-inflammatory and antiradiation metabolites. CONCLUSIONS: The probiotic consortium attenuated RIII by modulating the gut microbiota and metabolites, improving inflammatory symptoms, and regulating oxidative stress. These findings provide new insights into the maintenance of intestinal health with probiotic consortium supplementation and will facilitate the development of probiotic-based therapeutic strategies for RIII in clinical practice.

5.
Int Immunopharmacol ; 129: 111637, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38335653

RESUMO

The small intestine exhibits remarkable sensitivity to ionizing radiation (IR), which significantly hampers the effectiveness of radiotherapy in the treatment of abdominal and pelvic tumors. Unfortunately, no effective medications are available to treat radiation-induced intestinal damage (RIID). Fraxin (7-hydroxy-6-methoxycoumarin 8-glucoside), is a coumarin derivative extracted from the Chinese herb Cortex Fraxini. Several studies have underscored the anti-inflammatory, antibacterial, antioxidant, and immunomodulatory properties of fraxin. However, the efficacy of fraxin at preventing or mitigating RIID remains unclear. Thus, the present study aimed to investigate the protective effects of fraxin against RIID in vitro and in vivo and to elucidate the underlying mechanisms. The study findings revealed that fraxin markedly ameliorated intestinal injuries induced by 13 Gy whole abdominal irradiation (WAI), which was accompanied by a significant increase in the population of Lgr5+ intestinal stem cells (ISCs) and Ki67+ progeny. Furthermore, fraxin mitigated WAI-induced intestinal barrier damage, and reduced oxidative stress and intestinal inflammation in mice. Transcriptome sequencing of fraxin-treated mice revealed upregulation of IL-22, a pleiotropic cytokine involved in regulating the function of intestinal epithelial cells. Moreover, in both human intestinal epithelial cells and ex vivo cultured mouse intestinal organoids, fraxin effectively ameliorated IR-induced damage by promoting the expression of IL-22. The radioprotective effects of fraxin were partially negated in the presence of an IL-22-neutralizing antibody. In summary, fraxin is demonstrated to possess the ability to alleviate RIID and maintain intestinal homeostasis, suggesting that fraxin might serve as a strategy for mitigating accidental radiation exposure- or radiotherapy-induced RIID.


Assuntos
Cumarínicos , Intestinos , Camundongos , Humanos , Animais , Cumarínicos/farmacologia , Cumarínicos/uso terapêutico , Antioxidantes , Radiação Ionizante
6.
Radiat Prot Dosimetry ; 200(6): 525-537, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38411255

RESUMO

In Monte Carlo particle transport simulations, point flux tallying is a variance reduction technique that performs well with small detectors and finds broad application in source-detector problems and local point dose calculations. However, its use in large-scale point flux tallying computation adds substantial computational time. To address this issue, we propose a CPU-GPU-coupled acceleration method, which separates the complex logic and computationally intensive parts of particle transport calculation and assigns them to the CPU and GPU, respectively. This proposed method greatly enhances the efficiency of large-scale point flux tallies, providing significant convenience for subsequent dose calculations and other related steps. We validated our method by comparing the performance of a pure CPU program with our CPU-GPU accelerated program using the NUREG/CR-6115 PWR benchmark problem. The results indicate identical outcomes for photon point flux estimation, with the accelerated program being ~50 times faster.


Assuntos
Simulação por Computador , Modelos Moleculares , Método de Monte Carlo , Apresentação de Dados , Fótons
7.
Elife ; 122023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987602

RESUMO

An imbalance of the gut microbiota, termed dysbiosis, has a substantial impact on host physiology. However, the mechanism by which host deals with gut dysbiosis to maintain fitness remains largely unknown. In Caenorhabditis elegans, Escherichia coli, which is its bacterial diet, proliferates in its intestinal lumen during aging. Here, we demonstrate that progressive intestinal proliferation of E. coli activates the transcription factor DAF-16, which is required for maintenance of longevity and organismal fitness in worms with age. DAF-16 up-regulates two lysozymes lys-7 and lys-8, thus limiting the bacterial accumulation in the gut of worms during aging. During dysbiosis, the levels of indole produced by E. coli are increased in worms. Indole is involved in the activation of DAF-16 by TRPA-1 in neurons of worms. Our finding demonstrates that indole functions as a microbial signal of gut dysbiosis to promote fitness of the host.


Assuntos
Proteínas de Caenorhabditis elegans , Animais , Escherichia coli/fisiologia , Disbiose , Caenorhabditis elegans/fisiologia , Longevidade/fisiologia , Bactérias , Indóis
8.
BMC Gastroenterol ; 23(1): 72, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36915042

RESUMO

BACKGROUND AND AIMS: In recent years, more and more inflammatory indicators have been studied to predict the long-term survival of patients with ampullary carcinoma (AC) after radical resection, but these prognostic indicators are still controversial. Therefore, based on previous inflammation scores, this study established a novel, easily accessible, more feasible and more predictive prognostic marker [Carbohydrate antigen199 to gamma-glutamyltransferase ratio (CA19-9/GGT)] to better assess the prognostic significance in AC patients undergoing radical resection. METHODS: Overall survival (OS) and recurrence-free survival (RFS) were analyzed by Cox regression model. Correlation between CA19-9/GGT and clinicopathological variables were analyzed by Chi-squared test, Fisher ' s exact test, independent sample t test and Mann-Whitney U test. The performance of prognostic indexes is compared by the consistency index (C-index). The prediction accuracy of nomogram is further confirmed by calibration curve and decision curve analysis (DCA). RESULTS: CA19-9/GGT was an independent risk factor affecting OS [P = 0.001, hazard ratio (HR) 2.459, 95% confidence intervals (CI) 1.450-4.167] and RFS (P = 0.002, HR 2.333, 95% CI 1.371-3.971) in multivariate analysis. The optimal cut-off value of CA19-9/GGT was 0.14. In CA19-9/GGT correlation analysis, high risk group (> 0.14) was significantly associated with poor prognosis. The predictive performance of CA19-9/GGT (OS: C-index = 0.753, RFS: C-index = 0.745) was confirmed to be superior to other prognostic indicators according to the C-index. Compared with the simple AJCC staging system, the Nomogram prediction model (OS: C-index = 0.787, RFS: C-index = 0.795) established by the combination of CA19-9/GGT and AJCC 8th TNM staging system has higher prediction accuracy. CONCLUSIONS: CA19-9/GGT was an independent prognostic indicator after radical resection of AC. Incorporating CA19-9/GGT into the AJCC TNM staging system optimized the prediction accuracy of the TNM staging system, and further verified the predictive value of CA19-9/GGT.


Assuntos
Ampola Hepatopancreática , Antígeno CA-19-9 , Neoplasias , gama-Glutamiltransferase , Humanos , Ampola Hepatopancreática/cirurgia , Antígeno CA-19-9/sangue , Estadiamento de Neoplasias , Nomogramas , Prognóstico , Neoplasias/cirurgia , gama-Glutamiltransferase/sangue
9.
Sci China Life Sci ; 66(3): 439-452, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680676

RESUMO

The maintenance of proteostasis is essential for cellular and organism healthspan. How proteostasis collapse influences reproductive span remains largely unclear. In Caenorhabditis elegans, excess accumulation of vitellogenins, the major components in yolk proteins, is crucial for the development of the embryo and occurs throughout the whole body during the aging process. Here, we show that vitellogenin accumulation leads to reproduction cessation. Excess vitellogenin is accumulated in the intestine and transported into the germline, impairing lysosomal activity in these tissues. The lysosomal function in the germline is required for reproductive span by maintaining oocyte quality. In contrast, autophagy and sperm depletion are not involved in vitellogenin accumulation-induced reproductive aging. Our findings provide insights into how proteome imbalance has an impact on reproductive aging and imply that improvement of lysosomal function is an effective approach for mid-life intervention for maintaining reproductive health in mammals.


Assuntos
Proteínas de Caenorhabditis elegans , Vitelogeninas , Animais , Masculino , Vitelogeninas/genética , Vitelogeninas/metabolismo , Sêmen/metabolismo , Envelhecimento , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Lisossomos/metabolismo , Mamíferos
10.
Nat Prod Res ; 37(15): 2517-2524, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35319322

RESUMO

A new oleanane-type triterpene, ardisiapunine A (1), together with eight known compounds were isolated from the roots of Ardisia lindleyana D.Dietr. Their chemical structures were determined by means of spectroscopic methods including HR-ESI-MS and (1 D, 2 D) NMR data. The absolute configuration of compound 1 was established by a single-crystal X-ray diffraction experiment. The new compound is an unusual oleanane-type triterpene bearing an acetal and a C-13-C-18 double bond. The cytotoxicity of all isolated compounds were evaluated using four human cancer cell lines, including A549, HepG2, HeLa and U87. The new compound 1 and compound 2 were weakly active but the known compound 6 exhibited a high cytotoxicity compared to cisplatin.


Assuntos
Antineoplásicos Fitogênicos , Antineoplásicos , Ardisia , Saponinas , Triterpenos , Humanos , Ardisia/química , Triterpenos/farmacologia , Triterpenos/química , Estrutura Molecular , Células HeLa , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Saponinas/química
11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-993065

RESUMO

The ultra-high dose rate (UHDR) radiation has less side effect while keep comparable tumor control effect with conventional dose rate (CONV) radiation, which was named Flash effect. Recently, the Flash effect has been reported in many animal experiments with various types of radiations, animal species and body parts. However, the underlying mechanism of Flash has still been unraveled, making difficulties for the clinical application. This review pointed out the differences between the Flash effect and the UHDR effect in vitro and proposed three key scientific questions of Flash effect based on three well-known hypotheses, i. e., oxygen depletion, peroxyl radical recombination and immune cell protection. Finally, the research progresses and challenges of Flash mechanism study are concluded in order to give a clue for further deep investigation.

12.
J Med Virol ; 94(8): 3840-3846, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35441419

RESUMO

Viral diarrhea is one of the leading causes of morbidity and mortality in children. This study was conducted to disclose the etiological cause and epidemiological features of viral diarrhea among children in China. From 2009 to 2021, active surveillance was performed on pediatric patients with acute diarrhea and tested for five enteric viruses. Positive detection was determined in 65.56% (3325/5072) patients and an age-specific infection pattern was observed. A significantly higher positive rate was observed in 12-23-month-old children for rotavirus (47.46%) and adenovirus (7.06%), while a significantly higher positive rate was observed for norovirus (37.62%) in 6-11-month-old patients, and for astrovirus (11.60%) and sapovirus (10.79%) in 24-47-month-old patients. A higher positive rate of rotavirus in girls and norovirus in boys was observed only among 6-11 months of patients. We also observed more norovirus among patients from rural areas in the 0-5- and 36-47-month groups and more rotavirus among those from rural areas in the 12-23-month group. Diarrhea severity was greater for rotavirus in the 6-23-month group and norovirus in the 6-11-month group. Coinfections were observed in 29.26% (973/3325) of positive patients, and were most frequently observed between rotavirus and others (89.31%). Our findings could help the prediction, prevention, and potential therapeutic approaches to viral diarrhea in children.


Assuntos
Infecções por Adenovirus Humanos , Infecções por Enterovirus , Norovirus , Rotavirus , Fatores Etários , Criança , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Fezes , Feminino , Humanos , Lactente , Masculino , Norovirus/genética , Estações do Ano
13.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-965806

RESUMO

Objective To establish a sourceless efficiency calibration method by coupling Monte Carlo simulation with analytical calculation. Methods Monte Carlo simulation was used to calculate the point-to-point detection efficiency of specific detectors to establish a detection efficiency grid. The detection efficiency of point source, disc, cylindrical, beaker, spherical, U-tube and Marlin cup samples was analyzed using numerical integration method after detection efficiency grid interpolation. Results The above coupling method was used for sourceless efficiency calibration. Within the energy range of 0.2–3 MeV, the relative deviation of calibration between coupling method and Monte Carlo simulation was mostly less than 10%, the maximum relative deviation was 18.06%, and the computation time was reduced by at least 86%. The above coupling method was used for sourceless efficiency calibration of an HPGe detector manufactured by ORTEC for point source detection, which was in good agreement with the experimental calibration, and the relative deviations were less than 10%. Conclusion This method can be generalized and used in the sourceless efficiency calibration of HPGe, LaBr3, and NaI detectors.

14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-956864

RESUMO

Objective:To describe the distribution of volumetric breast density(VBD) in different ages of Chinese women based on X-ray mammograms.Methods:Based on mammographic images of 1 140 patients from January 2010 to December 2016 in a hospital in Beijing, the VBD of women was assessed by Volpara 1.5.1 and graded according to breast imaging reporting and data system published by American College of Radiology. The patients were divided into two groups according to the median age, and the two independent samples t-test was used to compare them. The patients were also divided into four groups according to age ( <40 years, 40-49 years, 50-59 years, ≥ 60 years), and the breast thickness, breast volume, glandular volume, and VBD were compared using a One-way ANOVA analysis. Results:The median age was 50 years. The compressed breast thickness and breast volume in patients over 50 years were significantly higher than those in patients below 50 years ( t= -8.99, -7.92, P<0.001), while glandular volume and VBD were significantly lower than those below 50 years ( t= 8.11, 18.49, P<0.001). The compressed breast thickness, breast volume, glandular volume, and VBD were statistically significant different among four groups ( F=27.10, 22.34, 25.70, 122.03, P<0.001). Patients over 60 years had the lowest VBD ( t=-12.56, -15.27, -4.57, P<0.001). VBD was negatively correlated with ages ( r=0.47, P<0.001). Conclusions:The compressed breast thickness and breast volume increased with ages, while the glandular volume and VBD decreased with ages.

15.
Front Microbiol ; 12: 709849, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34594310

RESUMO

Human parechoviruses (HPeVs) are important causes of infection in children. However, without a comprehensive and persistent surveillance, the epidemiology and clinical features of HPeV infection remain ambiguous. We performed a hospital-based surveillance study among three groups of pediatric patients with acute respiratory infection (Group 1), acute diarrhea (Group 2), and hand, foot and mouth disease (Group 3) in Chongqing, China, from 2009 to 2015. Among 10,212 tested patients, 707 (6.92%) were positive for HPeV, with the positive rates differing significantly among three groups (Group 1, 3.43%; Group 2, 14.94%; Group 3, 3.55%; P < 0.001). The co-infection with other pathogens was detected in 75.2% (531/707) of HPeV-positive patients. Significant negative interaction between HPeV and Parainfluenza virus (PIV) (P = 0.046, OR = 0.59, 95% CI = 0.34-0.98) and positive interactions between HPeV and Enterovirus (EV) (P = 0.015, OR = 2.28, 95% CI = 1.23-4.73) were identified. Among 707 HPeV-positive patients, 592 (83.73%) were successfully sequenced, and 10 genotypes were identified, with HPeV1 (n = 396), HPeV4 (n = 86), and HPeV3 (n = 46) as the most frequently seen. The proportion of genotypes differed among three groups (P < 0.001), with HPeV1 and HPeV4 overrepresented in Group 2 and HPeV6 overrepresented in Group 3. The spatial patterns of HPeV genotypes disclosed more close clustering of the currently sequenced strains than those from other countries/regions, although they were indeed mixed. Three main genotypes (HPeV1, HPeV3, and HPeV4) had shown distinct seasonal peaks, highlighting a bi-annual cycle of all HpeV and two genotypes (HPeV 1 and HPeV 4) with peaks in odd-numbered years and with peaks in even-numbered years HPeV3. Significantly higher HPeV1 viral loads were associated with severe diarrhea in Group 2 (P = 0.044), while associated with HPeV single infection than HPeV-EV coinfection among HFMD patients (P = 0.001). It's concluded that HPeV infection was correlated with wide clinical spectrum in pediatric patients with a high variety of genotypes determined. Still no clinical significance can be confirmed, which warranted more molecular surveillance in the future.

16.
Biochem Biophys Res Commun ; 562: 36-42, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34034091

RESUMO

There are six different longevity models in Caenorhabditis elegans. Previous studies have identified several convergence points, such as hlh-30, daf-16, and klf-3, required for lifespan extension in these longevity models. However, it is not clear whether there other such convergence points. In this study, based on analysis of transcriptome data, we found that the expression of klo-1/klotho was elevated in several longevity models. klo-1 was required for lifespan extension in the glp-1(e2141) and isp-1(qm150) mutants. klo-1 extended the lifespan of glp-1(e2141) and isp-1(qm150) worms by activating extracellular-signal-regulated kinase (ERK). In addition, klo-1 and mpk-1 (the homologous gene encoding ERK) regulated autophagy in glp-1(e2141) mutants, suggesting that klo-1 regulates lifespan by activating autophagy.


Assuntos
Autofagia , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Caenorhabditis elegans/fisiologia , Celulases/metabolismo , Longevidade , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Celulases/genética , Sistema de Sinalização das MAP Quinases , Mutação/genética
17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-910390

RESUMO

Objective:To measure the microdosimetric spectrum of carbon ion beam and calculate the relative biological effect (RBE) distribution, so as to provide reference for radiotherapy microdosimetric research.Methods:A silicon on insulator (SOI) microdosimeter was used to measure the microdosimetric spectrum of 12C ion beam, at 260 MeV/u, provided by Lanzhou Heavy Ion Accelerator National Laboratory. The measured pulse amplitude spectrum was converted to obtain the dose distribution. The microdosimetric spectra and RBE values at different polymethyl methacrylate depths were measured by the combination of different thickness PMMA. Results:The microdosimetric spectra of 12C ion beam at 260 MeV/u were measured at different PMMA depths, and the relationship between dose line energy yD and RBE and different PMMA depths was also obtained. The measurement result showed that the RBE value reached a peak of 2.6 at the PMMA depth of 116.5 mm, and decreased rapidly after the Bragg peak. However, the RBE value was still 1.3 at the trailing point, which was about twice as much as the entrance of the flat zone. Conclusions:This paper provides basic data for carbon ion beam microdosimetric spectroscopy through measurement. The RBE value of 12C ion beam gradually rises and reaches a peak with the increase of PMMA depth. After the Bragg peak position, it drops rapidly, but the biological effect at the tail cannot be ignored. At the same time, it reflects the dose fraction caused by different line energy intervals, and provides a reference for assessing the risk of heavy ion therapy for secondary cancer.

18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-910322

RESUMO

Objective:The Chinese pediatric mesh-type reference phantoms were developed and applied in the dose assessment of X-ray radiography.Methods:The 5- and 10-year-old Chinese pediatric mesh-type reference phantoms were developed based on the CT data. Based on the phantoms, the Monte Carlo method was applied to simulate the X-ray radiography to calculate the organ dose conversion coefficient and the effective dose conversion coefficient in different radiography conditions.Results:The 5- and 10-year-old Chinese pediatric mesh-type reference phantoms were developed, and the physical parameters were consistent with the national standard. The differences of the organ mass between the established phantoms and reference data were within 2%. The database of the pediatric chest posteroanterior projection and abdominal anteroposterior projection, tube voltage 60-90 kVp, total filtration 2.5~4 mmAl were simulated, and the difference between the effective dose conversion factor and the literature result was within 3%.Conclusions:The established Chinese pediatric mesh-type reference phantoms can be applied in the studies of radiation protection and clinical medicine and their result can provide an important reference for the dose assessment of the pediatric X-ray radiography.

19.
Talanta ; 210: 120652, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31987200

RESUMO

Here, the novel petal-shaped ionic liquids modified covalent organic frameworks (PS-IL-COFs) particles have been synthesized by using ionic liquids as modifying agent, which could be beneficial to avoid the aggregation of COFs during the preparation and improve its dispersing performance. The novel PS-IL-COFs particles have been used and evaluated in the one step cleanup and extraction (OSCE) procedure for human plasma prior to the analysis of 3 general anesthetics by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). In the OSCE procedure, human plasma samples are directly mixed with extraction solvent and PS-IL-COFs particles, and the extraction and cleanup procedure have been carried out simultaneously. Compared with the Oasis PRiME HLB cartridge method, the OSCE procedure using PS-IL-COFs particles as sorbents is much more effective for the minimization of ion suppression resulted from blood phospholipids. Under optimal conditions, the PS-IL-COFs particles show higher cleanup efficiency of 3 general anesthetics with recoveries in the range of 82.5%-115%. The limits of quantification (LOQs) for propofol, ketamine and etomidate are 0.18 µg/L, 0.15 µg/L and 0.016 µg/L, respectively. Validation results on linearity, specificity, precision and trueness, as well as on the application to analysis of general anesthetics in a case of a 54-year-old female suffered gallstone demonstrate the applicability to clinical studies.


Assuntos
Anestésicos/sangue , Etomidato/sangue , Líquidos Iônicos/química , Ketamina/sangue , Compostos Orgânicos/química , Propofol/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Pessoa de Meia-Idade , Tamanho da Partícula , Propriedades de Superfície , Espectrometria de Massas em Tandem
20.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-868899

RESUMO

Objective:To analyze the optimal preoperative timing of indocyanine green administration to do the fluorescence imaging during laparoscopic cholecystectomy.Methods:A total of 102 patients with laparoscopic cholecystectomy from January 2019 to November 2019 were retrospectively analyzed in this study, including 42 male patients and 60 female patients with an average age of 49(15-87) years old. The preoperative timing of indocyanine green (2.5 mg/ml, 1 ml) administration was set at 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 h before surgery, 12, 7, 8, 6, 6, 7, 8, 10, 8, 8, 8, 7, 7 patients, respectively. The intraoperative fluorescence imaging and signal contrast were compared.Results:Comparing with 0.5h group, the liver fluorescence intensities in 5, 6, 7, 8, 9, 10, 11 and12 h groups were significantly decreased (all P<0.05). There were no differences in the fluorescence intensities of the gallbladder, gallbladder duct, common bile duct and common liver duct between those groups with different injection timepoints (all P>0.05), and signal contrast was significantly lower in 0.5 h group than patients in 6, 7, 8, 9, 10, 11 and 12 h groups (all P<0.05). When preoperative timing of indocyanine green administration was 7 h, the fluorescence signal contrast reached the highest values of 0.29. Conclusions:The optimal preoperative timing of indocyanine green intravenous administration for laparoscopic cholecystectomy under fluorescence navigation was 7 h at dose 2.5 mg.

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