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1.
Opt Express ; 32(7): 11873-11885, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571025

RESUMEN

In recent years, the rotational Doppler effect (RDE) has been widely used in rotational motion measurement. However, the performance of existing detection systems based on the RDE are generally limited by the drastic reduction of signal-to-noise ratio (SNR) due to the influence of atmospheric turbulence, partial obscuration of the vortex beam (VB) during propagation, and misalignment between the optical axis of VB and the rotational axis of the object, which poses a challenge for practical applications. In this paper, we proposed a coherent detection method of the RDE measurement based on triple Fourier transform. First, the weak RDE signal in backscattered light is amplified by using the balanced homodyne detection method, and the amplified signal still retains the same characteristic of severe broadening in the frequency domain as the original signal. Furthermore, we proposed the triple Fourier transform to extract the broadened RDE frequency shift signal after the coherent amplification. The proposed method significantly improves the SNR of RDE measurement and facilitates the accurate extraction of rotational speed, which helps to further improve the RDE detection range and promote its practical application.

2.
Ecotoxicol Environ Saf ; 275: 116250, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38552387

RESUMEN

Forests emit a large amount of biogenic volatile organic compounds (BVOCs) in response to biotic and abiotic stress. Despite frequent occurrence of large forest fires in recent years, the impact of smoke stress derived from these forest fires on the emission of BVOCs is largely unexplored. Thus, the aims of the study were to quantify the amount and composition of BVOCs released by two sub-tropical tree species, Cunninghamia lanceolata and Schima superba, in response to exposure to smoke. Physiological responses and their relationship with BVOCs were also investigated. The results showed that smoke treatments significantly (p < 0.001) promoted short-term release of BVOCs by C. lanceolata leaves than S. superba; and alkanes, olefins and benzene homologs were identified as major classes of BVOCs. Both C. lanceolata and S. superba seedlings showed significant (p < 0.005) physiological responses after being smoke-stressed where photosynthetic rate remained unaffected, chlorophyll content greatly reduced and Activities of anti-oxidant enzymes and the malondialdehyde content generally increased with the increase in smoke concentration. Activities of anti-oxidant enzymes showed mainly positive correlations with the major BVOCs. In conclusion, the release of BVOCs following smoke stress is species-specific and there exists a link between activities of antioxidant enzymes and BVOCs released. The findings provide insight about management of forest fires in order to control excessive emission of smoke that would trigger increased release of BVOCs.


Asunto(s)
Compuestos Orgánicos Volátiles , Incendios Forestales , Árboles , Antioxidantes , Fumar
3.
J Sci Food Agric ; 104(6): 3570-3584, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38150568

RESUMEN

BACKGROUND: Tea pests pose a significant threat to tea leaf yield and quality, necessitating fast and accurate detection methods to improve pest control efficiency and reduce economic losses for tea farmers. However, in real tea gardens, some tea pests are small in size and easily camouflaged by complex backgrounds, making it challenging for farmers to promptly and accurately identify them. RESULTS: To address this issue, we propose a real-time detection method based on TP-YOLOX for monitoring tea pests in complex backgrounds. Our approach incorporates the CSBLayer module, which combines convolution and multi-head self-attention mechanisms, to capture global contextual information from images and expand the network's perception field. Additionally, we integrate an efficient multi-scale attention module to enhance the model's ability to perceive fine details in small targets. To expedite model convergence and improve the precision of target localization, we employ the SIOU loss function as the bounding box regression function. Experimental results demonstrate that TP-YOLOX achieves a significant performance improvement with a relatively small additional computational cost (0.98 floating-point operations), resulting in a 4.50% increase in mean average precision (mAP) compared to the original YOLOX-s. When compared with existing object detection algorithms, TP-YOLOX outperforms them in terms of mAP performance. Moreover, the proposed method achieves a frame rate of 82.66 frames per second, meeting real-time requirements. CONCLUSION: TP-YOLOX emerges as a proficient solution, capable of accurately and swiftly identifying tea pests amidst the complex backgrounds of tea gardens. This contribution not only offers valuable insights for tea pest monitoring but also serves as a reference for achieving precise pest control. © 2023 Society of Chemical Industry.


Asunto(s)
Algoritmos , Árboles , Humanos , Agricultores , Jardinería ,
4.
Mol Psychiatry ; 27(4): 2095-2105, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35115700

RESUMEN

The ability to remember conspecifics is critical for adaptive cognitive functioning and social communication, and impairments of this ability are hallmarks of autism spectrum disorders (ASDs). Although hippocampal ventral CA1 (vCA1) neurons are known to store social memories, how their activities are coordinated remains unclear. Here we show that vCA1 social memory neurons, characterized by enhanced activity in response to memorized individuals, were preferentially reactivated during sharp-wave ripples (SPW-Rs). Spike sequences of these social replays reflected the temporal orders of neuronal activities within theta cycles during social experiences. In ASD model Shank3 knockout mice, the proportion of social memory neurons was reduced, and neuronal ensemble spike sequences during SPW-Rs were disrupted, which correlated with impaired discriminatory social behavior. These results suggest that SPW-R-mediated sequential reactivation of neuronal ensembles is a canonical mechanism for coordinating hippocampus-dependent social memories and its disruption underlie the pathophysiology of social memory defects associated with ASD.


Asunto(s)
Trastorno Autístico , Amnesia , Animales , Hipocampo/fisiología , Ratones , Proteínas de Microfilamentos , Proteínas del Tejido Nervioso , Neuronas/fisiología
5.
Appl Microbiol Biotechnol ; 107(12): 3899-3909, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37148336

RESUMEN

Sakuranetin is a plant-natural product, which has increasingly been utilized in cosmetic and pharmaceutical industries for its extensive anti-inflammatory, anti-tumor, and immunomodulatory effects. Sakuranetin was mostly produced by extraction technology from plants, which is limited to natural conditions and biomass supply. In this study, a de novo biosynthesis pathway of sakuranetin by engineered S. cerevisiae was constructed. After a series of heterogenous gene integration, a biosynthetic pathway of sakuranetin from glucose was successfully constructed in S. cerevisiae whose sakuranetin yield reached only 4.28 mg/L. Then, a multi-module metabolic engineering strategy was applied for improving sakuranetin yield in S. cerevisiae: (1) adjusting the copy number of sakuranetin synthesis genes, (2) removing the rate-limiting factor of aromatic amino acid pathway and optimizing the synthetic pathway of aromatic amino acids to enhance the supply of carbon flux for sakuranetin, and (3) introducing acetyl-CoA carboxylase mutants ACC1S659A,S1157A and knocking out YPL062W to strengthen the supply of malonyl-CoA which is another synthetic precursor of sakuranetin. The resultant mutant S. cerevisiae exhibited a more than tenfold increase of sakuranetin titer (50.62 mg/L) in shaking flasks. Furthermore, the sakuranetin titer increased to 158.65 mg/L in a 1-L bioreactor. To our knowledge, it is the first report on the sakuranetin de novo synthesis from glucose in S. cerevisiae. KEY POINTS: • De novo biosynthesis of sakuranetin was constructed by engineered S. cerevisiae. • Sakuranetin production was enhanced by multi-module metabolic engineering strategy. • It is the first report on the sakuranetin de novo synthesis in S. cerevisiae.


Asunto(s)
Glucosa , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Glucosa/metabolismo , Flavonoides/metabolismo , Ingeniería Metabólica
6.
BMC Anesthesiol ; 23(1): 189, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37259069

RESUMEN

BACKGROUND: Decreased bioavailability of nitric oxide (NO) under hypoxic conditions can lead to endothelial dysfunction. NO supplementation may protect endothelial function in ischemia-reperfusion (IR) injury. Therefore, a meta-analysis of randomized controlled trials (RCTs) was performed to verify the protective effect of NO donors on endothelium in IR injury. METHODS: Medline, Embase, Cochrane Library, and Web of Science databases were searched from inception to April 1, 2023. The specific inclusion criteria were as follows: (1) RCTs; (2) trials comparing NO donors with placebo control groups; and (3) trials reporting the effects of these interventions on vascular endothelial functional outcomes in IR injury. Random-effects models were used to assess pooled effect sizes, which were expressed as standardized mean differences (SMD). RESULTS: Seven studies satisfied the inclusion criteria and consisted of a total of 149 participants. NO donors were protective of endothelial function in IR injury (SMD: - 1.60; 95% confidence interval [CI]: - 2.33, - 0.88, P < 0.0001; heterogeneity [I2 = 66%, P = 0.001]). Results of the subgroup analysis showed the following: absence of protective effect of NO donor use following ischemia on endothelial function in IR injury - 1.78 (95% CI: - 2.50, - 1.07) and loss of protective effect on endothelial function after prolonged NO donor use - 0.89 (95% CI: - 2.06, 0.28). CONCLUSION: The short-period use of NO donors before the onset of ischemia can protect endothelial function in IR injury.


Asunto(s)
Donantes de Óxido Nítrico , Daño por Reperfusión , Humanos , Donantes de Óxido Nítrico/farmacología , Donantes de Óxido Nítrico/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Endotelio Vascular , Daño por Reperfusión/prevención & control , Óxido Nítrico
7.
BMC Anesthesiol ; 22(1): 312, 2022 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-36203158

RESUMEN

BACKGROUND: Misplacement of double-lumen endobronchial tubes (DLTs) during bronchial intubation, especially when bronchoscopy guidance is not applicable, threatens effective lung isolation and brings about airway injury during reposition. We aimed to examine whether a novel maneuver called right tracheal displacement (RTD) can reduce left-sided DLT misplacement during first-attempt intubation without bronchoscopy guidance. METHODS: Patients that underwent thoracic surgeries requiring one-lung ventilation during November 2020 to January 2021 were recruited and randomized into control and RTD group, with 54 cases in each group. The primary outcomes included the incidence of DLT misplacement and the time to complete desired bronchial intubation. The secondary outcomes included mucosal injury, sore throat and hoarseness upon emergence and at 24 h post-operatively. RESULT: The incidence of DLT misplacement in RTD group was significantly lower compared to control group (0% vs. 16.7%) The time to complete bronchial intubation was also significantly shortened in RTD group compared to control (52.88 ± 9.36 s vs. 63.04 ± 20.02 s). The incidence of mucosal injury, sore throat and hoarseness were comparable between two groups. CONCLUSION: RTD maneuver can effectively improve the success rate of first-attempt proper DLT positioning and shorten the time required by bronchial intubation. TRIAL REGISTRATION: This prospective, double-blind, randomized study has completed the registration of the Chinese Clinical Trial Center at 2/11/2020 with the registration number ChiCTR2000040212. It was conducted from 26/11/2020 to 31/7/2021 in third affiliated hospital of Sun Yat-sen university.


Asunto(s)
Faringitis , Tráquea , Broncoscopía/efectos adversos , Ronquera/etiología , Ronquera/prevención & control , Humanos , Intubación Intratraqueal/efectos adversos , Faringitis/etiología , Faringitis/prevención & control , Estudios Prospectivos
8.
Financ Res Lett ; 50: 103322, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36119390

RESUMEN

This paper investigates the effect of the COVID-19 pandemic on analysts' forecast dispersion. We find that analysts' exposure to the COVID-19 lockdown reduces the dispersion of their forecasts. Along with the forecast dispersion, the number of earnings forecasts issued by treated analysts decreases, supporting the channel of attention distraction. Moreover, there is no significant difference between optimistic and pessimistic forecasts, against the explanation of risk attitude change. We find our conclusion is robust to a staggered DID model and numerous robustness tests. Our finding contributes to the dispute regarding the pandemic's effect on analyst forecast behavior.

9.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 51(3): 267-277, 2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-36207836

RESUMEN

OBJECTIVE: To investigate the disease burden of congenital heart disease (CHD) in China from 1990 to 2019. METHODS: Using the data from Global Burden of Disease (GBD) study 2019, the incidence, age-standardized incidence rates, the mortality, age-standardized mortality rates, disability-adjusted life year (DALY) and age-standardized DALY rates of CHD were calculated. Time trend analysis of disease burden-related indicators was analyzed by Joinpoint regression model. Age-period-cohort model was used to describe age, period, and birth cohort effects in CHD mortality population. The relationship between age-standardized incidence, mortality, DALY rates of congenital heart disease and human development index (HDI) were analyzed by Pearson correlation. RESULTS: From 1990 to 2019, the mean annual percentage change (AAPC) in age-standardized incidence rate, mortality rate and DALY rate of CHD in China were -0.1%(95% CI: -0.7%-0.4%)、-3.5%(95% CI: -3.7%--3.2%) and -3.5%(95% CI: -3.7%--3.2%), respectively. CHD usually occurred in the first year of life. The mean incidence rate at birth was 2497.9/100 000, and the mean incidence rate under 1 year of age was 2626.6/100 000. During the period of 1995-2000, the incidence rate in newborn and <1 year children showed an exponential upward trend, then it remained a steady downward trend. However, there was an exponential increase in <1 year children during 2010-2013 and 2014-2015, followed by an exponential decrease to the lowest value in the last three decades. The mortality of CHD tended to decrease with age, with mortality of 101.67/100 000 for children under 5 years of age and a decrease after 5 years of age. However, there was a transient increase in mortality in age group 55-<60. From 1995 to 2019, the relative risk of death of patients with CHD showed a downward trend. Compared with 1995-1999, the rate ratio of death decreased by 24% in 2015-2019. Such downward trend was also observed in the birth cohort after 1945. Compared with the 1945-1949 birth cohort, the rate ratio of death for patients with CHD decreased by 75% in the 2015-2019 birth cohort. When HDI<0.58 (before 1999), the age-standardized incidence of CHD was positively correlated with HDI ( r=0.74, P<0.05). When HDI≥0.58 (after 1999), the age-standardized incidence of CHD was negatively correlated with HDI ( r=-0.76, P<0.01). The age-standardized mortality and DALY rates were negatively correlated with HDI ( r=-0.95 and -0.93, both P<0.01). CONCLUSIONS: During 1990 to 1999, the incidence of CHD increases and is positively correlated with the social development. During 1999 to 2019, the incidence of CHD decreases and is negatively correlated with the social development. The disease burden of CHD decreases and is negatively correlated with the social development. Some progress has been made in the field of prevention and control of CHD, but the disease burden remains high among younger population in China.


Asunto(s)
Costo de Enfermedad , Cardiopatías Congénitas , Niño , Preescolar , China/epidemiología , Cardiopatías Congénitas/epidemiología , Humanos , Incidencia , Recién Nacido , Años de Vida Ajustados por Calidad de Vida
10.
Proc Natl Acad Sci U S A ; 115(33): 8406-8411, 2018 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-30065117

RESUMEN

Several previous genomic studies have focused on adaptation to high elevations, but these investigations have been largely limited to endotherms. Snakes of the genus Thermophis are endemic to the Tibetan plateau and therefore present an opportunity to study high-elevation adaptations in ectotherms. Here, we report the de novo assembly of the genome of a Tibetan hot-spring snake (Thermophis baileyi) and then compare its genome to the genomes of the other two species of Thermophis, as well as to the genomes of two related species of snakes that occur at lower elevations. We identify 308 putative genes that appear to be under positive selection in Thermophis We also identified genes with shared amino acid replacements in the high-elevation hot-spring snakes compared with snakes and lizards that live at low elevations, including the genes for proteins involved in DNA damage repair (FEN1) and response to hypoxia (EPAS1). Functional assays of the FEN1 alleles reveal that the Thermophis allele is more stable under UV radiation than is the ancestral allele found in low-elevation lizards and snakes. Functional assays of EPAS1 alleles suggest that the Thermophis protein has lower transactivation activity than the low-elevation forms. Our analysis identifies some convergent genetic mechanisms in high-elevation adaptation between endotherms (based on studies of mammals) and ectotherms (based on our studies of Thermophis).


Asunto(s)
Aclimatación/fisiología , Altitud , Serpientes/genética , Alelos , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Evolución Molecular , Femenino , Endonucleasas de ADN Solapado/genética , Genoma , Hipoxia , Filogenia , Selección Genética , Serpientes/fisiología , Tibet , Rayos Ultravioleta
11.
Ecotoxicol Environ Saf ; 215: 112141, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33740491

RESUMEN

Current Chinese surface water environmental quality standard GB3838-2002 for ammonia fails to take water quality factors and native organism distributions in different basins into consideration. In this study, ammonia toxicity tests were performed using three aquatic organisms native to the Shaying River Basin (China). Published ammonia toxicity data with pH and temperature, and toxicity data acquired in this study were used to establish water quality criteria. The final criterion maximum concentration (CMC) and criterion continuous concentration (CCC) for the Shaying River Basin were 5.09 and 1.36 (mg total ammonia nitrogen (TAN))/L (pH 7 and 20 °C), respectively. In addition, based on the corresponding relationship between ammonia toxicity and temperature and pH, the ecological risk assessment of ammonia was conducted in different seasons for the Shaying River using a tiered approach of both hazard quotient (HQ) and the joint probability (JPC) methods. Two methods gave consistent results: the ecological risks of ammonia to aquatic species in the Shaying River Basin were severe and the risk could be ranked as wet season > flat season > dry season. It is therefore indicating that monitoring, evaluation, and early warning of ammonia pollution need to be taken to prevent and control the risks posed by ammonia pollution, especially for wet season (because of high temperatures and pH) or flat season (because of high pH values). We hope the present work could provide valuable information to manage and control ammonia pollution in the Shaying River Basin.


Asunto(s)
Amoníaco/análisis , Contaminantes Químicos del Agua/análisis , Amoníaco/toxicidad , Organismos Acuáticos , China , Monitoreo del Ambiente/métodos , Nitrógeno , Medición de Riesgo/métodos , Ríos/química , Estaciones del Año , Pruebas de Toxicidad , Contaminantes Químicos del Agua/toxicidad , Calidad del Agua/normas
12.
J Neurochem ; 152(2): 221-234, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31390677

RESUMEN

Histone deacetylase 6 (HDAC6) activity contributes to the malignant proliferation, invasion, and migration of glioma cells (GCs), but the molecular mechanisms underlying the processes remains elusive. Here, we reported that HDAC6 inhibition by Ricolinostat (ACY-1215) or CAY10603 led to a remarkable decrease in the phosphorylation of c-Jun N-terminal kinase (JNK) and c-Jun, which preceded its suppressive effects on glioma cell growth. Further investigation showed that these effects resulted from HDAC6 inhibitor-induced suppression of MAPK kinase 7 (MKK7), which was identified to be critical for JNK activation and exerts the oncogenic roles in GCs. Selectively silencing HDAC6 by siRNAs had the same responses, whereas transient transfections expressing HDAC6 promoted MKK7 expression. Interestingly, by performing Q-PCR, HDAC6 inhibition did not cause a down-regulation of MKK7 mRNA level, whereas the suppressive effects on MKK7 protein can be efficiently blocked by the proteasomal inhibitor MG132. As a further test, elevating MKK7-JNK activity was sufficient to rescue HDAC6 inhibitor-mediated-suppressive effects on c-Jun activation and the malignant features. The suppression of both MKK7 expression and JNK/c-Jun activities was involved in the tumor-growth inhibitory effects induced by CAY10603 in U87-xenograft mice. Collectively, our findings provide new insights into the molecular mechanism of glioma malignancy regarding HDAC6 in the selective regulation of MKK7 expression and JNK/c-Jun activity. MKK7 protein stability critically depends on HDAC6 activity, and inhibition of HDAC6 probably presents a potential strategy for suppressing the oncogenic roles of MKK7/JNK/c-Jun axis in GCs.


Asunto(s)
Procesos de Crecimiento Celular/fisiología , Glioblastoma/metabolismo , Histona Desacetilasa 6/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , MAP Quinasa Quinasa 4/metabolismo , MAP Quinasa Quinasa 7/metabolismo , Animales , Procesos de Crecimiento Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Glioblastoma/patología , Histona Desacetilasa 6/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
13.
Dev Growth Differ ; 62(9): 507-515, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33112441

RESUMEN

To be social, the ability to recognize and discriminate conspecific individuals is indispensable in social animals, including primates, rodents, birds, fish, and social insects which live in societies or groups. Recent studies using molecular biology, genetics, in vivo and in vitro physiology, and behavioral neuroscientific approaches have provided detailed insights into how animals process and recognize the information of individuals. Here, we review the most distinct sensory modalities for individual recognition in animals, namely, olfaction and vision. In the case of rodents, two polymorphic gene complexes have been identified in their urine as the key and essential pheromonal components for individual recognition: the major histocompatibility complex (MHC) and the major urinary protein (MUP). Animals flexibly utilize MHC and/or MUP, which are detected by the main olfactory epithelium (MOE) and/or the vomeronasal organ (VNO) for various types of social recognition, such as strain recognition, kin recognition, and individual recognition. In contrast, primates, including humans, primarily use facial appearance to identify others. Face recognition in humans and other animals is naturally unique from genetic, cognitive, developmental, and functional points of view. Importantly note that nurture effects during growth phase such as social experience and environment can also shape and tune this special cognitive ability, in order to distinguish subtle differences between individuals. In this review, we address such unique nature and nurture mechanisms for individual recognition.


Asunto(s)
Olfato , Visión Ocular , Animales , Complejo Mayor de Histocompatibilidad , Proteínas/metabolismo , Órgano Vomeronasal/metabolismo
14.
Zhongguo Zhong Yao Za Zhi ; 45(23): 5599-5606, 2020 Dec.
Artículo en Zh | MEDLINE | ID: mdl-33496097

RESUMEN

Based on fingerprint and network pharmacology,the whole process quality control of Zhuru Decoction was conducted and efficacy-related substances were predicted.The fingerprints of raw materials,decoction pieces and Zhuru Decoction were established,and 25 common peaks were identified,including 9 common chromatographic peaks of 3'-hydroxy puerarin,puerarin,3'-methoxy puerarin,puerarin,aperioside,daidzin,daidzein,liquiritin,glycyrrhizic acid and 6-gingerol, with similarity all greater than 0.95.The main groups of pharmacodynamic substances can be transferred from raw materials,decoction pieces to Zhuru Decoction step by step,with a clear affiliation relationship.Based on the testability and traceability,the active ingredients were screened,and the network relationship of "component-target-pathway" was constructed and analyzed for the nine chemical components screened by network pharmacology.The enriched pathways included energy metabolism,alcoholism,and smooth muscle contraction and relaxation-related pathways.The nine active components of Zhuru Decoction may achieve the effects of clearing heat, alleviating a hangover, harmonizing stomach and stopping vomiting through these signaling pathways.Based on transitive and traceable properties of the above 9 components as well as their close relationship to the efficacy of Zhuru Decoction,these 9 components can be identified as potential efficacy-related substances and provide basis for the overall quality control of Zhuru Decoction.


Asunto(s)
Medicamentos Herbarios Chinos , Ácido Glicirrínico , Prescripciones , Control de Calidad
15.
Int J Cancer ; 145(9): 2496-2508, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30963560

RESUMEN

JNK activity has been implicated in the malignant proliferation, invasion and drug-resistance of glioma cells (GCs), but the molecular mechanisms underlying JNK activation are currently unknown. Here, we reported that MKK7, not MKK4, directly activates JNK in GCs and exerts oncogenic effects on tumor formation. Notably, MKK7 expression in glioma tissues was closely correlated with the grade of the glioma and JNK/c-Jun activation. Mechanistically, MKK7 transcription critically depends on the complexes formed by HDAC4 and the transcriptional factors SP1 and Krüppel-like factor-5 (KLF5), wherein HDAC4 directly deacetylates both SP1 and KLF5 and synergistically upregulates MKK7 transcription through two SP1 sites located on its promoter. In contrast, the increases in acetylated-SP1 and acetylated-KLF5 after HDAC4 inhibition switched to transcriptionally suppress MKK7. Selective inhibition of HDAC4 by LMK235, siRNAs or blockage of SP1 and KLF5 by the ectopic dominant-negative SP1 greatly reduced the malignant capacity of GCs. Furthermore, suppression of both MKK7 expression and JNK/c-Jun activities was involved in the tumor-growth inhibitory effects induced by LMK235 in U87-xenograft mice. Interestingly, HDAC4 is highly expressed in glioma tissues, and the rate of HDAC4 nuclear import is closely correlated with glioma grade, as well as with MKK7 expression. Collectively, these findings demonstrated that highly expressed MKK7 contributes to JNK/c-Jun signaling-mediated glioma formation. MKK7 transcription, regulated by SP1 and KLF5, critically depends on HDAC4 activity, and inhibition of HDAC4 presents a potential strategy for suppressing the oncogenic roles of MKK7/JNK/c-Jun signaling in GCs.


Asunto(s)
Glioma/genética , Histona Desacetilasas/genética , Factores de Transcripción de Tipo Kruppel/genética , MAP Quinasa Quinasa 7/genética , Proteínas Represoras/genética , Factor de Transcripción Sp1/genética , Animales , Línea Celular Tumoral , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Sistema de Señalización de MAP Quinasas/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Regiones Promotoras Genéticas/genética , Transcripción Genética/genética , Activación Transcripcional/genética , Regulación hacia Arriba/genética
16.
BMC Microbiol ; 19(1): 219, 2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31533609

RESUMEN

BACKGROUND: The molecular characterization of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) isolates is not well studied. Our goal was to investigate the molecular epidemiology of CR-hvKP strains that were isolated from a Chinese hospital. RESULTS: All clinical carbapenem-resistant K. pneumoniae (CR-KP) isolates were collected and identified from patient samples between 2014 and 2017 from a Chinese hospital. The samples were subjected to screening for CR-hvKP by string test and the detection of the aerobactin gene. CR-hvKP isolates were further confirmed through neutrophil phagocytosis and a mice lethality assay. The CR-hvKP isolates were investigated for their capsular genotyping, virulence gene profiles, and the expression of carbapenemase genes by PCR and DNA sequencing. Multilocus sequence type (MLST) and pulsed-field gel electrophoresis (PFGE) were performed to exclude the homology of these isolates. Twenty strains were identified as CR-hvKP. These strains were resistant to imipenem and several other antibiotics, however, most were susceptible to amikacin. Notably, two isolates were not susceptible to tigecycline. Capsular polysaccharide synthesis genotyping revealed that 17 of the 20 CR-hvKP strains belonged to the K2 serotype, while the others belonged to serotypes other than K1, K2, K5, K20, and K57. The strains were found to be positive for 10 types of virulence genes and a variety of these genes coexisted in the same strain. Two carbapenemase genes were identified: blaKPC-2 (13/20) and blaNDM-1 (1/20). PFGE typing revealed eight clusters comprising isolates that belonged to MLST types ST25, ST11 and ST375, respectively. PFGE cluster A was identified as the main cluster, which included 11 isolates that belong to ST25 and mainly from ICU department. CONCLUSIONS: Our findings suggest that hospital-acquired infections may contribute in part to the CR-hvKP strains identified in this study. It also suggests that ST25 CR-hvKP strain has a clonal distribution in our hospital. Therefore, effective surveillance and strict infection control strategies should be implemented to prevent outbreak by CR-hvKP strains in hospitals setting.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/patogenicidad , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Animales , Antibacterianos/farmacología , Cápsulas Bacterianas/genética , Proteínas Bacterianas/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Carbapenémicos/farmacología , China/epidemiología , Genotipo , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/aislamiento & purificación , Ratones , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Serogrupo , Virulencia/genética , beta-Lactamasas/genética
17.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2051-2058, 2019 May.
Artículo en Zh | MEDLINE | ID: mdl-31355560

RESUMEN

To establish ultra performance liquid chromatography( UPLC) fingerprint of Puerariae Lobatae Radix from different habitats and simultaneously determine the contents of six isoflavonoids. The UPLC fingerprint analysis and content determination were performed on a Waters ACQUITY UPLC BEH C_(18)( 2. 1 mm×50 mm,1. 7 µm) chromatographic column,with acetonitrile-0. 05% formic acid as mobile phase for gradient elution. The detection wavelength was set at 250 nm; the flow rate was 0. 2 mL·min~(-1); the column temperature was 30 ℃ and the injection volume was 2 µL. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( TCM) was adopted; principal component analysis( PCA) and discriminant analysis by partial least square method( PLS-DA) in Simca-P software were used to identify the differential components in samples from three habitats. The similarity was over 0. 90 in 29 batches of samples,indicating good consistency of the samples. The samples were clustered into 3 categories by PCA and PLS-DA,and six differential components such as puerarin apioside,daidzin,and isoflavoues aglycone were found. The determination results of 6 isoflavones,including 3'-hydroxy puerarin,puerarin,3'-methoxy puerarin,puerarin apioside,daidzin,and isoflavoues aglycone,showed that the content of the same component and the fluctuation range between different components were all different among different habitats. The total content of 6 isoflavones from different regions was Anhui 11. 21% >Henan 10. 97% >Shannxi 9. 38%. The establishment of UPLC fingerprint combined with simultaneous determination of 6 active components provides a more comprehensive reference for quality control and quality evaluation of Puerariae Lobatae Radix.


Asunto(s)
Medicamentos Herbarios Chinos/química , Ecosistema , Flavonoides/análisis , Pueraria/química , Cromatografía Líquida de Alta Presión , Fitoquímicos/análisis , Raíces de Plantas/química
18.
J Sep Sci ; 41(11): 2310-2320, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29473301

RESUMEN

We established a rapid and sensitive ultra high-performance liquid chromatography tandem mass spectrometry method for the simultaneous quantification of xanthones and steroidal saponins in rat plasma. Chromatographic separation was achieved on a C18 column with a mobile phase comprising acetonitrile and 0.1% formic acid. The detection was performed by negative electrospray ionization in multiple reaction monitoring mode. The validated method showed good linearity within the tested range (r > 0.9945). The intra- and interday precision at high, medium, and low concentrations was less than 7.96%. The bias of accuracies ranged from -1.92 to 9.62%. The extraction recoveries of the compounds ranged from 84.78 to 88.69%, and the matrix effects ranged from 96.76 to 108.59%. This method was successfully applied to a pharmacokinetic comparison of crude and salt-processed Anemarrhenae Rhizoma aqueous extracts after oral administration in rats. The maximum plasma concentration and area under concentration-time curve of timosaponin BIII and timosaponin AIII increased significantly (P < 0.05 or 0.01) and those of timosaponin BII decreased significantly (P < 0.05) after processing. These results could contribute to the clinical application of crude and salt-processed Anemarrhenae Rhizoma and reveal the processing mechanism.


Asunto(s)
Anemarrhena/química , Cromatografía Líquida de Alta Presión/métodos , Medicamentos Herbarios Chinos/análisis , Saponinas/análisis , Espectrometría de Masas en Tándem/métodos , Xantonas/análisis , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Rizoma/química , Saponinas/administración & dosificación , Saponinas/aislamiento & purificación , Xantonas/administración & dosificación , Xantonas/aislamiento & purificación
19.
BMC Genomics ; 18(1): 666, 2017 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-28851270

RESUMEN

BACKGROUND: TEs pervade mammalian genomes. However, compared with mice, fewer studies have focused on the TE expression patterns in rat, particularly the comparisons across different organs, developmental stages and sexes. In addition, TEs can influence the expression of nearby genes. The temporal and spatial influences of TEs remain unclear yet. RESULTS: To evaluate the TEs transcription patterns, we profiled their transcript levels in 11 organs for both sexes across four developmental stages of rat. The results show that most short interspersed elements (SINEs) are commonly expressed in all conditions, which are also the major TE types with commonly expression patterns. In contrast, long terminal repeats (LTRs) are more likely to exhibit specific expression patterns. The expression tendency of TEs and genes are similar in most cases. For example, few specific genes and TEs are in the liver, muscle and heart. However, TEs perform superior over genes on classing organ, which imply their higher organ specificity than genes. By associating the TEs with the closest genes in genome, we find their expression levels are correlated, independent of their distance in some cases. CONCLUSIONS: TEs sex-dependently associate with nearest genes. A gene would be associated with more than one TE. Our works can help to functionally annotate the genome and further understand the role of TEs in gene regulation.


Asunto(s)
Elementos Transponibles de ADN/genética , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Caracteres Sexuales , Animales , Femenino , Genómica , Masculino , Especificidad de Órganos , Ratas
20.
Molecules ; 23(1)2017 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-29271935

RESUMEN

The present study was designed to systematically investigate the chemical profile differences between crude Anemarrhenae rhizoma (CAR) and salt-processed Anemarrhenae rhizoma (SAR). Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS), coupled with multivariate statistical analysis was used for the discrimination of chemical profiles and the identification of the differentiation of the chemical constitutions of CAR and SAR. In addition, seven main constituents of CAR and SAR were simultaneously determined by ultra-high-performance liquid chromatography-quadrupole mass spectrometry (UHPLC-MS) for analyzing the content variations. A total of 24 components were found to be the main contributors to the significant difference between CAR and SAR. The structures of the marker compounds were identified based on their chromatographic behaviors, intact precursor ions, and characteristic MS fragmentation patterns. The potential structural transformation mechanism of furostanol saponins during salt processing was explored. The results may provide a scientific foundation for deeply elucidating the processing mechanism of Anemarrhenae rhizoma.


Asunto(s)
Anemarrhena/química , Extracción Líquido-Líquido/métodos , Saponinas/aislamiento & purificación , Cloruro de Sodio/química , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas , Extractos Vegetales/química , Análisis de Componente Principal , Rizoma/química
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