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1.
Neuroimage ; 282: 120398, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37778420

RESUMEN

Magnetic Resonance Imaging (MRI) is widely applied in medical diagnosis due to its excellent non-invasiveness. With the increasing intensity of static magnetic field (SMF), the safety assessment of MRI has been ongoing. In this study, zebrafish larvae were exposed to SMFs of 0.4, 3.0, and 9.4 T for 2 h (h), and we found that there was no significant difference in the number of spontaneous tail swings, heart rate, and body length of zebrafish larvae in the treatment groups. The expression of development-related genes shha, pygo1, mylz3 and runx2b in the three SMF groups was almost not significantly different from the control group. Behavior tests unveiled a notable reduction in both the average speed and duration of high-speed movements in zebrafish larvae across all three SMF groups. In addition, the 0.4 and 3.0 T SMFs increased the migration of neutrophils in caudal fin injury, and the expression of pro-inflammatory cytokines was also increased. To explore the mechanism of SMFs on zebrafish immune function, this study utilized aanat2-/- mutant fish to demonstrate the effect of melatonin (MT) involvement in SMFs on zebrafish immune function. This study provides experimental data for understanding the effects of SMFs on organisms, and also provides a new insight for exploring the relationship between magnetic fields and immune function.


Asunto(s)
Campos Magnéticos , Pez Cebra , Animales , Inmunidad
2.
Food Technol Biotechnol ; 61(3): 283-293, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38022876

RESUMEN

Research background: Chilling injury is a major disorder affecting the quality of tropical and subtropical vegetables during low temperature storage. Snap bean (Phaseolus vulgaris L.) is sensitive to chilling injury. The main purpose of the present study is to investigate the alleviating effects of 1-methylcyclopropene (1-MCP) on chilling injury of snap bean. In addition, the related mechanisms were also detected from the perspective of the changes of antioxidant defense system. Experimental approach: Snap beans were exposed to different volume fractions of 1-MCP. After 24 h of treatment, snap beans were stored at 4 °C for up to 14 days. Chilling injury index, electrolyte leakage, titratable acidity and total soluble solids were determined. Contents of chlorophyll, ascorbic acid and malondialdehyde were assessed. The total antioxidant capacity, Fe(II) ion chelating capacity, scavenging capacities on free radicals and activities of antioxidant enzymes were detected. Total phenol content and activities of related metabolic enzymes were also determined. Results and conclusions: 1-MCP treatment reduced chilling injury index, electrolyte leakage rate and malondialdehyde content of snap beans. The amounts of total soluble solids, titratable acid, ascorbic acid and total chlorophyll in 1-MCP-treated snap beans were significantly higher than those of control. The snap beans treated with 1-MCP showed stronger total antioxidant capacity and metal chelating activity. The 1-MCP treatment enhanced scavenging effects of snap beans on superoxide, hydroxyl and 1,1-diphenyl-2-trinitrophenylhydrazine radicals. The activities of peroxidase, ascorbate peroxidase, superoxide dismutase and catalase in 1-MCP-treated group were higher than of control. The treatment also enhanced the accumulation of phenolic compounds in snap beans by regulating the activities of phenol-metabolizing enzymes such as shikimate dehydrogenase, phenylalanine ammonia lyase enzyme, cinnamic acid 4-hydroxylase and polyphenol oxidase. In conclusion, with the mechanism that involves the activation of enzymatic and non-enzymatic antioxidant systems, 1-MCP has the ability to avoid chilling injury of snap bean. Novelty and scientific contribution: This study gives insights into whether 1-MCP can regulate postharvest cold resistance in vegetables by enhancing the enzymatic antioxidant system and inducing the accumulation of non-enzymatic antioxidants. Considering the results, 1-MCP treatment could be an effective method to alleviate postharvest chilling injury of snap beans during low temperature storage.

3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(5): 782-788, 2023 May 28.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37539581

RESUMEN

Leiomyosarcoma of urinary bladder (LMS-UB) is a highly malignant mesenchymal tumor, accounting for less than 0.5% of all bladder malignancies, with a predominant clinical presentation of hematuria. Here we report a case of low-grade LMS-UB. A 44-year-old male patient was admitted to the hospital with urodynia for 2 weeks. The patient's pelvis CT showed a mass on the right part of the bladder. For this reason, he was initially diagnosed with bladder cancer. We performed a robot-assisted laparoscopic enucleation of the bladder tumor and low-grade LMS-UB was diagnosed with the histopathological examination. He underwent 5 cycles of adjuvant chemotherapy after surgery. At 19months postoperative follow-up, the patient had no symptoms, recurrence, or distant metastasis. There is no report on the treatment of LMS-UB with minimally invasive enucleation worldwide. This case provides a new comprehensive treatment method of enucleation combined with adjuvant chemotherapy for early low-grade LMS-UB to reduce complications and improve patients' quality of life after surgery.


Asunto(s)
Laparoscopía , Leiomiosarcoma , Robótica , Neoplasias de la Vejiga Urinaria , Masculino , Humanos , Adulto , Vejiga Urinaria/cirugía , Leiomiosarcoma/cirugía , Leiomiosarcoma/diagnóstico , Leiomiosarcoma/secundario , Calidad de Vida , Pelvis/patología , Neoplasias de la Vejiga Urinaria/cirugía , Neoplasias de la Vejiga Urinaria/patología , Laparoscopía/métodos
4.
Anal Biochem ; 643: 114575, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35085546

RESUMEN

During the manufacturing of therapeutic proteins, Critical Quality Attributes (CQAs) have been monitored by conventional methods, such as cation exchange chromatography (CEX), reduced capillary electrophoresis-sodium dodecyl sulfate (rCE-SDS), and 1,2-diamino-4,5-methylenedioxybenzene (DMB) labelling method. The conventional methods often generate individual peaks that contain multiple components, which may obscure the detection and the quantification of individual critical quality attributes (CQAs). Alternatively, Multi-Attribute Method (MAM) enables detection and quantification of specific CQAs. A high resolution MAM has been developed and qualified to replace several conventional methods in monitoring product quality attributes, such as oxidation, deamidation, clipping, and glycosylation. The qualified MAM was implemented in process characterization, as well as release and stability assays in quality control (QC). In combination with a design-of-experiments (DoE), the MAM method identified multivariate process parameter ranges that yield acceptable CQA level, which provides operational flexibility for manufacturing.


Asunto(s)
Proteínas/análisis , Cromatografía por Intercambio Iónico , Electroforesis Capilar , Fenilendiaminas/química , Control de Calidad , Dodecil Sulfato de Sodio/química
5.
Fish Shellfish Immunol ; 125: 212-219, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35569778

RESUMEN

Normal dissolved oxygen in water is essential for maintaining the physiological functions of fish, but environmental pollution, such as eutrophication can lead to a decrease in oxygen content in water. How this reduction of dissolved oxygen in water affects the immune functions of fish and the potential regulatory mechanisms have not been thoroughly elucidated. In this study, we made full use of the aquatic model animal zebrafish to explore this question. In a model of LPS-induced inflammation, we found that hypoxia induced by infusing nitrogen into water increased the expression of pro-inflammatory cytokines, such as il-1ß, il-6, and il-8. In vivo imaging also showed that hypoxia significantly increased neutrophil migration to the site of caudal fin injury in the transgenic line. Subsequently, we found that the phosphorylation level of ERK protein was significantly activated upon hypoxia and proved the roles of ERK signaling in the expression of pro-inflammatory cytokines and neutrophil migration in zebrafish. This study indicated that reduced water oxygen significantly increases the inflammatory response of the zebrafish.


Asunto(s)
Citocinas , Pez Cebra , Animales , Citocinas/genética , Citocinas/metabolismo , Hipoxia/genética , Inflamación/inducido químicamente , Inflamación/genética , Neutrófilos , Oxígeno/metabolismo , Agua , Pez Cebra/genética , Pez Cebra/metabolismo
6.
Mol Divers ; 25(4): 2379-2388, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32734588

RESUMEN

A series of novel pyrazole-4-carboxamides were rationally designed, synthesized, and their structures were characterized by 1H NMR, 13C NMR and HRMS. Preliminary bioassay showed that four compounds 8g, 8j, 8o and 8s exhibited more than 90% and even completed inhibition against Alternaria solani at 100 µg/mL; and 8d displayed 100% inhibition against Fusarium oxysporum at the same concentration. Moreover, 8j exhibited good in vitro fungicidal activity against A. solani with EC50 value of 3.06 µg/mL, and it also displayed completed in vivo protective antifungal activity against A. solani on tomato at 10 mg/L, as boscalid did. The molecular docking results indicated that 8j exhibited the high affinity with SDH protein by H-bond and π-π stacking interactions, which may explain the reasons for its good activities. These data support that compound 8j could be used as a fungicide candidate for further study. A practical method for the synthesis of pyrazole-4-carboxamides were provided and evaluation of their antifungal activities.


Asunto(s)
Fungicidas Industriales
7.
BMC Microbiol ; 20(1): 239, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32753060

RESUMEN

BACKGROUND: Probiotics have been reported to reduce total cholesterol levels in vitro, but more evidence is needed to determine the clinical relevance of this activity. Chinese traditional fermented pickles are a good source of lactic acid bacteria. Therefore, pickle samples were collected for screening lactic acid bacteria based on their ability to survive stresses encountered during gastrointestinal passage and cholesterol reducing potency. RESULTS: Seventy five lactic acid bacteria strains were isolated from 22 fermented pickles. From these bacteria, Lactobacillus plantarum E680, showed the highest acid (85.25%) and bile tolerance (80.79%). It was sensitive to five of the eight antibiotics tested, inhibited the growth of four pathogenic bacteria, and reduced the total cholesterol level by 66.84% in broth culture. In vivo testing using hypercholesterolemic mice fed high-fat emulsion, independent of food intake, found that L. plantarum E680 suppressed body weight gain and reduced total cholesterol and low-density lipoprotein cholesterol levels, with no effect on high-density lipoprotein cholesterol. CONCLUSIONS: Chinese traditional fermented pickles are a good source for probiotics. L. plantarum E680, isolated from pickles, was acid and bile tolerant, sensitive to antibiotics, and reduced cholesterol levels both in vitro and in vivo. Based on these results, L. plantarum E680 may have potential as a novel probiotic for the development of cholesterol-lowering functional food.


Asunto(s)
Hipercolesterolemia/tratamiento farmacológico , Lactobacillus plantarum/fisiología , Probióticos , Ácidos/metabolismo , Animales , Antibacterianos/farmacología , Antibiosis , Anticolesterolemiantes/farmacología , Anticolesterolemiantes/uso terapéutico , Ácidos y Sales Biliares/metabolismo , Peso Corporal/efectos de los fármacos , Cucumis sativus , Alimentos Fermentados/microbiología , Hipercolesterolemia/sangre , Hipercolesterolemia/patología , Lactobacillales/efectos de los fármacos , Lactobacillales/aislamiento & purificación , Lactobacillales/fisiología , Lactobacillus plantarum/efectos de los fármacos , Lactobacillus plantarum/aislamiento & purificación , Lípidos/sangre , Ratones , Probióticos/administración & dosificación , Probióticos/farmacología
8.
FASEB J ; 33(6): 7721-7733, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30893562

RESUMEN

Calcium is an important messenger in the neuronal system, but its specific role in axonal regeneration has not been fully investigated. To clarify it, we constructed a noninvasive in vivo calcium-imaging model of zebrafish Mauthner cells and monitored subcellular calcium dynamics during axonal regeneration. Using the calcium indicator GCamp6f, we observed that the regenerative length correlated with the peak amplitude of the evoked calcium response before axotomy, which suggested that the evoked calcium response might serve as a useful indicator of evoked neuronal activity and axonal regenerative capacity. To investigate this possibility, we overexpressed an inward rectifying potassium channel protein, Kir2.1a, to decrease the Mauthner neuronal activity and found that the inhibition of the calcium response correlated with decreased axonal regeneration. In contrast, treatment of pentylenetetrazol and knockout of the sodium voltage-gated channel α subunit 1 gene increased the calcium response and thus enhanced axonal regeneration. Our results therefore increased the understanding of the correlation between the neural activity and the vertebrate axonal regeneration.-Chen, M., Huang, R.-C., Yang, L.-Q., Ren, D.-L., Hu, B. In vivo imaging of evoked calcium responses indicates the intrinsic axonal regenerative capacity of zebrafish.


Asunto(s)
Axones/metabolismo , Calcio/metabolismo , Regeneración Nerviosa , Pez Cebra/fisiología , Animales , Animales Modificados Genéticamente , Axotomía
9.
Toxicol Appl Pharmacol ; 365: 71-83, 2019 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-30633885

RESUMEN

Natural products derived from herbal medicines have become a major focus of anti-cancer drug discovery studies. Acetyl-macrocalin B (A-macB) is an ent-diterpenoid isolated from Isodon silvatica. This study aimed to examine the effect and molecular action of A-macB in esophageal squamous cell carcinoma (ESCC) and explore possible drug synergistic modalities. A-macB induced cellular reactive oxygen species (ROS) generation, initiated the p38 mitogen-activated protein kinase (MAPK) signaling pathway, and triggered the caspase-9-dependent apoptosis cascade in ESCC cells. The ROS scavenger N-acetylcysteine (NAC) and the specific p38 inhibitor SB203580 reversed the effects of A-macB on the p38 network and thus rescued ESCC cells from apoptosis. The cellular ROS increase was at least partially due to the suppression of glutathione-S-transferase P1 (GSTP1) by A-macB. A-macB also upregulated the Chk1/Chk2-Cdc25C/Cdc2/Cyclin B1 axis to induce G2/M phase arrest. The cell growth inhibition induced by A-macB was further enhanced by AZD7762, a specific Chk1/Chk2 inhibitor, with a combination index (CI) of <1. Moreover, A-macB efficiently suppressed xenograft growth without inducing significant toxicity, and AZD7762 potentiated the effects of A-macB in the suppression of tumor growth in vivo. Taken together, A-macB is a promising lead compound for ESCC and exerts synergistic anti-cancer effects with AZD7762.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Proliferación Celular/efectos de los fármacos , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/antagonistas & inhibidores , Quinasa de Punto de Control 2/antagonistas & inhibidores , Diterpenos de Tipo Kaurano/farmacología , Neoplasias Esofágicas/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Tiofenos/farmacología , Urea/análogos & derivados , Animales , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Quinasa de Punto de Control 2/metabolismo , Sinergismo Farmacológico , Neoplasias Esofágicas/enzimología , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/enzimología , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Carga Tumoral/efectos de los fármacos , Urea/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
10.
Molecules ; 24(23)2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31795340

RESUMEN

Protoporphyrinogen oxidase (PPO) has been identified as one of the most promising targets for herbicide discovery. A series of novel phthalimide derivatives were designed by molecular docking studies targeting the crystal structure of mitochondrial PPO from tobacco (mtPPO, PDB: 1SEZ) by using Flumioxazin as a lead, after which the derivatives were synthesized and characterized, and their herbicidal activities were subsequently evaluated. The herbicidal bioassay results showed that compounds such as 3a (2-(4-bromo-2,6-difluorophenyl) isoindoline-1,3-dione), 3d (methyl 2-(4-chloro-1,3-dioxoisoindolin-2-yl)-5-fluorobenzoate), 3g (4-chloro-2-(5-methylisoxazol-3-yl) isoindoline-1,3-dione), 3j (4-chloro-2-(thiophen-2-ylmethyl) isoindoline-1,3-dione) and 3r (2-(4-bromo-2,6-difluorophenyl)-4-fluoroisoindoline-1,3-dione) had good herbicidal activities; among them, 3a showed excellent herbicidal efficacy against A. retroflexus and B. campestris via the small cup method and via pre-emergence and post-emergence spray treatments. The efficacy was comparable to that of the commercial herbicides Flumioxazin, Atrazine, and Chlortoluron. Further, the enzyme activity assay results suggest that the mode of action of compound 3a involves the inhibition of the PPO enzyme, and 3a showed better inhibitory activity against PPO than did Flumioxazin. These results indicate that our molecular design strategy contributes to the development of novel promising PPO inhibitors.


Asunto(s)
Inhibidores Enzimáticos , Herbicidas , Simulación del Acoplamiento Molecular , Proteínas de Plantas/antagonistas & inhibidores , Malezas/enzimología , Protoporfirinógeno-Oxidasa/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Herbicidas/síntesis química , Herbicidas/química , Herbicidas/farmacología , Ftalimidas/síntesis química , Ftalimidas/química , Ftalimidas/farmacología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Protoporfirinógeno-Oxidasa/química , Protoporfirinógeno-Oxidasa/metabolismo
11.
Fish Shellfish Immunol ; 80: 528-533, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29958979

RESUMEN

The circadian clock plays a critical role in regulating the immune system. Our previous publication revealed that a mutation in the circadian gene period1b (per1b) in zebrafish significantly decreased proinflammatory gene expression, particularly under constant darkness (DD) conditions; however, the underlying mechanisms remain unclear. In this study, using per1b-null mutant zebrafish and a larval tail fin injury model, we observed that the loss of per1b resulted in the downregulation expression of proinflammatory cytokines, such as IL-6 and TNF-α, at protein level. Furthermore, the loss of per1b downregulated ERK phosphorylation and inhibited p65 phosphorylation, leading to reduced NF-κB activation, which could downregulate the expression of proinflammatory cytokines, such as IL-6 and TNF-α, in zebrafish. These results provided insight into the communication between the circadian clock and immune functions.


Asunto(s)
Citocinas/inmunología , FN-kappa B/inmunología , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/inmunología , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/inmunología , Pez Cebra/genética , Pez Cebra/inmunología , Animales , Benzamidas/farmacología , Relojes Circadianos/inmunología , Difenilamina/análogos & derivados , Difenilamina/farmacología , Embrión no Mamífero , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/inmunología , Inflamación/inmunología , Larva , Mutación , Transducción de Señal , Cola (estructura animal)/lesiones
12.
Fish Shellfish Immunol ; 77: 139-146, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29605504

RESUMEN

The circadian clock has been shown to regulate various immune processes in different animals. Our previous report demonstrated that the innate immune responses in zebrafish show significant rhythmicity that could be regulated by melatonin. Here, we used diurnal zebrafish to determine the role of circadian genes in the inflammatory responses. Our results indicate that circadian genes exhibit rhythmic oscillations in zebrafish leukocytes, and mutations of the clock genes period1b (per1b) and period2 (per2) considerably affect these oscillations. Using a wounded zebrafish inflammation model, we found that under constant dark conditions (DD), the expression of pro-inflammatory cytokines is significantly downregulated in per1b gene mutant zebrafish and significantly upregulated in the per2 gene mutant zebrafish. Furthermore, using real-time imaging technology, we found that the per1b gene markedly disturbs the rhythmic recruitment of neutrophils toward the injury, whereas the per2 gene does not show a significant effect. Taken together, our results reveal differential functions of the circadian genes per1b and per2 in the inflammatory responses, serving as evidence that circadian rhythms play a vital role in immune processes.


Asunto(s)
Ritmo Circadiano/inmunología , Proteínas del Ojo/genética , Regulación de la Expresión Génica/inmunología , Inflamación/genética , Proteínas Circadianas Period/genética , Proteínas de Pez Cebra/genética , Pez Cebra/genética , Pez Cebra/inmunología , Animales , Proteínas del Ojo/inmunología , Inflamación/inmunología , Proteínas Circadianas Period/inmunología , Pez Cebra/lesiones , Proteínas de Pez Cebra/inmunología
13.
Phys Chem Chem Phys ; 20(29): 19424-19429, 2018 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-29992219

RESUMEN

A hybrid structure of carbon nanotubes and graphene nanoribbons was predicted and synthesized (Y. Li et al., Nat. Nanotechnol., 2012, 7, 394-400; P. Lou, J. Phys. Chem. C, 2014, 118, 4475-4482). Herein, using the non-equilibrium Green's function (NEGF) combined with density functional theory (DFT), the thermal spin transport properties and the figure of merit (a material constant proportional to the efficiency of a thermoelectric couple made with the material) of a composite of single-walled carbon nanotubes and zigzag-edge graphene nanoribbons, labeled (6,6)SWCNT/n-ZGNR, are investigated for n = 1, 2, 3, and 8. The results manifest that spin-dependent currents with opposite flow directions were generated when a temperature gradient was applied between two electrodes, indicating the occurrence of the spin-dependent Seebeck effect (SDSE). Remarkably, when n = 3, the charge current is equal to zero, meaning that a perfect SDSE is observed. Moreover, a pure spin-dependent Seebeck diode (SDSD) effect can be observed. Finally, we notice that the device presents an n-type characteristic when n = 1, while the device has a p-type feature when n = 2. In particular, the spin-up thermopower is equal to the spin-down thermopower when n = 3; as a consequence, the charge thermopower is equal to zero, further demonstrating that a perfect SDSE is generated. These discoveries indicate that the (6,6)SWCNT/n-ZGNR is a promising candidate for spin caloritronics devices.

14.
Phys Chem Chem Phys ; 20(11): 7701-7709, 2018 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-29498386

RESUMEN

Elucidating atmospheric oxidation mechanisms and the reaction kinetics of atmospheric compounds is of great importance and necessary for atmospheric modeling and the understanding of the formation of atmospheric organic aerosols. While the hydrolysis of aldehydes has been detected in the presence of sulfuric acid, the reaction mechanism and kinetics remain unclear. Herein, we use electronic structure methods with CCSD(T)/CBS accuracy and canonical variational transition state theory combined with small-curvature tunneling to study the reaction mechanism and kinetics of the hydrolysis of CH3CHO. The calculated results show that the hydrolysis of CH3CHO needs to overcome an energy barrier of 37.21 kcal mol-1, while the energy barrier is decreased to -9.79 kcal mol-1 with a sulfuric acid catalyst. In addition, the calculated kinetic results show that the H2SO4H2O + CH3CHO reaction is faster than H2SO4 + CH3CHOH2O. Additionally, the H2SO4H2O + CH3CHO reaction can play an important role in the sink of CH3CHO below 260 K occurring during the night period when OH, H2SO4, and H2O concentrations are 104, 108, and 1017 molecules cm-3, respectively, because it can compete well with the CH3CHO + OH reaction. There are wide implications in atmospheric chemistry from these findings because of the potential importance of the catalytic effect of H2SO4 on the hydrolysis of CH3CHO in the atmosphere and in the formation of secondary organic aerosols.

15.
J Nanosci Nanotechnol ; 18(5): 3274-3282, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29442828

RESUMEN

Nanofibrous silver (Ag)/poly(vinylidene fluoride) (PVDF) composite membranes were obtained from a two-step preparation method. In the first step, the electrospun silver nitrate (AgNO3)/PVDF membranes were prepared and the influence of the AgNO3 content on the electrospinning process was studied. According to scanning electron microscopy (SEM) results, when the electrospinning solution contained AgNO3 in the range between 3 to 7 wt.%, the nanofiber morphologies can be obtained. In the second step, the electrospun AgNO3/PVDF membranes were reduced by sodium borohydride to form the nanofibrous Ag/PVDF composite membranes. The resultant composite membranes were characterized by SEM, X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), differential scanning calorimetry, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared. The XRD, XPS, and EDS characterizations proved the existence of Ag in the nanofibrous Ag/PVDF composite membranes. The crystallinity degree of PVDF for composite membranes declined with the increase in Ag content. More importantly, the nanofibrous Ag/PVDF composite membranes had obviously higher Rosseland extinction coefficients and lower thermal radiative conductivities in comparison with electrospun PVDF membrane, which demonstrates that such composite membranes with high porosity, low density, and good water vapor permeability are promising thermal insulating materials to block the heat transfer resulting from thermal radiation. In addition, three different methods for surface modification have been used to successfully improve the hydrophobicity of nanofibrous Ag/PVDF composite membranes.

16.
Ann Surg Oncol ; 23(13): 4284-4292, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27464612

RESUMEN

PURPOSE: This study was designed to investigate the effectiveness of magnetic resonance imaging (MRI) in diagnosing prostate cancer (PCa) and high-grade prostate cancer (HGPCa) before transrectal ultrasound (TRUS)-guided biopsy. METHODS: The clinical data of 894 patients who received TRUS-guided biopsy and prior MRI test from a large Chinese center was reviewed. Based on Prostate Imaging Reporting and Data System (PI-RADS) scoring, all MRIs were re-reviewed and assigned as Grade 0-2 (PI-RADS 1-2; PI-RADS 3; PI-RADS 4-5). We constructed two models both in predicting PCa and HGPCa (Gleason score ≥ 4 + 3): Model 1 with MRI and Model 2 without MRI. Other clinical factors include age, digital rectal examination, PSA, free-PSA, volume, and TRUS. RESULTS: PCa and HGPCa were present in 434 (48.5 %) and 218 (24.4 %) patients. An MRI Grade 0, 1, and 2 were assigned in 324 (36.2 %), 193 (21.6 %) and 377 (42.2 %) patients, which was associated with the presence of PCa (p < 0.001) and HGPCa (p < 0.001). Particularly in patients aged ≤55 years, the assignment of MRI Grade 0 was correlated with extremely low rate of PCa (1/27) and no HGPCa. The c-statistic of Model 1 and Model 2 for predicting PCa was 0.875 and 0.841 (Z = 4.2302, p < 0.001), whereas for predicting HGPCa was 0.872 and 0.850 (Z = 3.265, p = 0.001). Model 1 exhibited higher sensitivity and specificity at same cutoffs, and decision-curve analysis also suggested the favorable clinical utility of Model 1. CONCLUSIONS: Prostate MRI before biopsy could predict the presence of PCa and HGPCa, especially in younger patients. The incorporation of MRI in nomograms could increase predictive accuracy.


Asunto(s)
Imagen por Resonancia Magnética , Nomogramas , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Anciano , Área Bajo la Curva , China , Tacto Rectal , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Valor Predictivo de las Pruebas , Antígeno Prostático Específico/sangre , Curva ROC , Factores de Riesgo
17.
J Comput Assist Tomogr ; 40(2): 272-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26760190

RESUMEN

OBJECTIVE: The aim of the study was to investigate the feasibility of low-tube-voltage computed tomography (CT) in combination with 3-dimensional adaptive iterative dose reduction (AIDR-3D) algorithm in lower extremity CT angiography. METHODS: The CT data of the 120-kV group (n = 30) were reconstructed with filtered back projection (FBP) algorithm. The CT data of the 100-kV group (n = 30) were reconstructed with FBP as well as AIDR-3D algorithms. RESULTS: The 100-kV group showed significantly lower dose-length product than the 120-kV group (P < 0.05). In comparison with the 120-kV and FBP protocol, the 100-kV and FBP protocol showed significantly increased vascular density and noise (P < 0.05). However, in the 100-kV group, images reconstructed with AIDR-3D showed significantly lower noise and significantly higher signal-to-noise ratio and contrast-to-noise ratio than FBP (P < 0.05). CONCLUSIONS: Low-tube-voltage (100 kV) 320-row CT in combination with AIDR-3D reconstruction can significantly improve the image quality and reduce radiation dose of lower extremity CT angiography.


Asunto(s)
Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/diagnóstico por imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Algoritmos , Angiografía/métodos , Estudios de Factibilidad , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Relación Señal-Ruido
18.
Int J Biometeorol ; 60(12): 1953-1960, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27192998

RESUMEN

Photooxidative damage to the needle leaves of evergreen trees results from the absorption of excess excitation energy. Efficient dissipation of this energy is essential to prevent photodamage. In this study, we determined the fluorescence transients, absorption spectra, chlorophyll contents, chlorophyll a/b ratios, and relative membrane permeabilities of needle leaves of Pinus koraiensis, Pinus tabulaeformis, and Pinus armandi in both cold winter and summer. We observed a dramatic decrease in the maximum fluorescence (F m) and substantial absorption of light energy in winter leaves of all three species. The F m decline was not correlated with a decrease in light absorption or with changes in chlorophyll content and chlorophyll a/b ratio. The results suggested that the winter leaves dissipated a large amount of excess energy as heat. Because the cold winter leaves had lost normal physiological function, the heat dissipation depended solely on changes in the photosystem II supercomplex rather than the xanthophyll cycle. These findings imply that more attention should be paid to heat dissipation via changes in the photosystem complex structure during the growing season.


Asunto(s)
Pinus/fisiología , Permeabilidad de la Membrana Celular , Clorofila/metabolismo , Frío , Fluorescencia , Calor , Complejo de Proteína del Fotosistema II/metabolismo , Pinus/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Estaciones del Año
19.
J Pineal Res ; 58(4): 452-60, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25763660

RESUMEN

The circadian clock plays a vital role in physiology and behavior such as the sleep-wake cycle and blood pressure and hormone levels. Immune responses also display circadian rhythmicity and particularly pineal melatonin contributes to immunological processes. Little attention, however, is given to mechanisms underlying rhythmic neutrophil responses to the injury. Here, we used a transgenic Tg(lyz:EGFP) zebrafish tail fin transection model to investigate whether the recruitment of neutrophils toward the injured site is regulated by the circadian clock. We found that migrating neutrophils display robust rhythmicity, peaking at darkness. Melatonin positively regulates rhythmic neutrophil migration, as evidenced that treatment with melatonin at low dosage can significantly enhance neutrophil recruitment toward the injured site, which is attenuated by luzindole treatment and in pinealectomized fish. Furthermore, using a transgenic zebrafish eyeball model, we observed that melatonin enhances secretion of two cytokines, TNF-α and IL-8, both of which markedly enhance neutrophil migration. Taken together, these results highlight a positive role of melatonin in rhythmic neutrophil migration and help obtain a better understanding of circadian regulation in immunology.


Asunto(s)
Melatonina/farmacología , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Animales , Ritmo Circadiano/efectos de los fármacos , Pez Cebra
20.
Analyst ; 140(6): 1876-85, 2015 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-25665981

RESUMEN

In this study, a new algorithm for wavelength interval selection, known as interval variable iterative space shrinkage approach (iVISSA), is proposed based on the VISSA algorithm. It combines global and local searches to iteratively and intelligently optimize the locations, widths and combinations of the spectral intervals. In the global search procedure, it inherits the merit of soft shrinkage from VISSA to search the locations and combinations of informative wavelengths, whereas in the local search procedure, it utilizes the information of continuity in spectroscopic data to determine the widths of wavelength intervals. The global and local search procedures are carried out alternatively to realize wavelength interval selection. This method was tested using three near infrared (NIR) datasets. Some high-performing wavelength selection methods, such as synergy interval partial least squares (siPLS), moving window partial least squares (MW-PLS), competitive adaptive reweighted sampling (CARS), genetic algorithm PLS (GA-PLS) and interval random frog (iRF), were used for comparison. The results show that the proposed method is very promising with good results both on prediction capability and stability. The MATLAB codes for implementing iVISSA are freely available on the website: .


Asunto(s)
Algoritmos , Espectroscopía Infrarroja Corta/métodos , Harina/análisis , Análisis de los Mínimos Cuadrados , Glycine max/química , Comprimidos/química , Zea mays/química
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