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1.
Zhen Ci Yan Jiu ; 49(5): 448-455, 2024 May 25.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38764115

RESUMEN

OBJECTIVES: To observe the effect of electroacupuncture (EA) at different intensities on nociceptive discharges of wide dynamic range (WDR) neurons in the spinal dorsal horns (DHs) of rats, so as to explore its regulatory characteristics on nociceptive signals at the spinal level. METHODS: A total of 25 male SD rats were used in the present study. A microelectrode array was used to record the discharge activity of WDR neurons in the lumbar spinal DHs of normal rats. After finding the WDR neuron, electrical stimulation (pulse width of 2 ms) was administered to the plantar receptive field (RF) for determining its response component of discharges according to the latency of action potential generation (Aß ï¼»0 to 20 msï¼½, Aδ ï¼»20 to 90 msï¼½, C ï¼»90 to 500 msï¼½ and post-discharge ï¼»500 to 800 msï¼½). High-intensity electrical stimulation was continuously applied to the RF at the paw's plantar surface to induce DHs neuronal windup response. Subsequently, EA stimulation at different intensities (1 mA and 2 mA) was applied to the left "Zusanli"(ST36) at a frequency of 2 Hz/15 Hz for 10 min. The induction of WDR neuronal windup was then repeated under the same conditions. The quantity of nociceptive discharge components and the windup response of WDR neurons before and after EA stimulations at different intensities were compared. RESULTS: Compared to pre-EA, both EA1 mA and EA2 mA significantly reduced the number of Aδ and C component discharges of WDR neurons during stimulation, as well as post-discharge (P<0.01, P<0.001). The inhibitory rate of C component by EA2 mA was significantly higher than that by EA1 mA (P<0.05). Meanwhile, both EA1 mA and EA2 mA attenuated the windup response of WDR neurons (P<0.05, P<0.01), and the effect of EA2 mA was stronger than that of EA1 mA (P<0.05). Further analysis showed that when EA1 mA and EA2 mA respectively applied to both non-receptive field (non-RF) and RF, a significant reduction in the number of Aδ component, C component and post-discharge was observed (P<0.05, P<0.01). EA2 mA at the non-RF and RF demonstrated a significant inhibitory effect on the windup response of WDR neurons (P<0.01, P<0.05), but EA1 mA only at the non-RF showed a significant inhibitory effect on the windup response (P<0.01). CONCLUSIONS: EA can suppress nociceptive discharges of spinal DHs WDR neurons in rats. The inhibitory impact of EA is strongly correlated with the location and intensity of EA stimulation, and EA2 mA has a stronger inhibitory effect than EA1 mA.


Asunto(s)
Puntos de Acupuntura , Electroacupuntura , Ratas Sprague-Dawley , Animales , Masculino , Ratas , Humanos , Nocicepción , Asta Dorsal de la Médula Espinal/fisiopatología , Células del Asta Posterior/fisiología , Potenciales de Acción
2.
Mitochondrial DNA B Resour ; 8(4): 479-483, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37063241

RESUMEN

Trees of Engelhardia are important components of subtropical and tropical forests in South-eastern Asia with great ecological and economic values. However, phylogenetic relationships within Engelhardioideae (Juglandaceae) remains obscure. In this study, we report the first complete chloroplast genome sequences of Engelhardia sensu stricto, Engelhardia hainanensis Chen, a rare species endemic in southern China. Its complete chloroplast genome is 161,574 bp in length, with a typical quadripartite structure that includes a large single-copy region of 91,158 bp, a small single-copy region of 18,790 bp, and its GC content is 35.8%. A total of 128 genes were identified, including 83 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Furthermore, a phylogenetic tree of Juglandaceae was constructed based the complete chloroplast genome sequence, which strongly support the three-subfamily classification system in Juglandaceae, and E. hainanensis was resolved sister to two Alfaropsis species. This study provides valuable genomic information for the species identification and phylogenetic study of Juglandaceae.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 294: 122558, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36863083

RESUMEN

Hydrazine (N2H4) can cause serious damage to human health, while intracellular viscosity is highly associated with many diseases and cellular dysfunctions. Herein, we report the synthesis of a dual-responsive organic molecule-based fluorescent probe with excellent water solubility being capable of detection of N2H4 and viscosity through dual-fluorescence channels in "turn on" manner for both. Besides sensitive detection of N2H4 in aqueous solution with detection limit of 0.135 µM, this probe could be used for vapor N2H4 detection in colorimetric and fluorescent manners. In addition, the probe demonstrated viscosity-dependent fluorescence enhancement behavior, and as high as 150-fold enhancement could be obtained at 95% glycerol aqueous solution. Cell imaging experiment revealed that the probe could be used for the discriminating of living and dead cells.


Asunto(s)
Sondas Moleculares , Agua , Humanos , Viscosidad , Espectrometría de Fluorescencia/métodos , Colorantes Fluorescentes , Hidrazinas , Células HeLa
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 291: 122384, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36689908

RESUMEN

Development of accurate and efficient TCs residue analysis methods is of great significance for the protection of environment, food safety and public health. Herein, a dual-responsive ratiometric fluorescence sensor being capable of simple and sensitive detection of tetracycline (TC) was presented, which was constructed by immobilizing europium ions (Eu3+) onto the mercaptopropionic acid stabilized copper nanoclusters (MPA-Cu NCs). In the presence of TC, the red fluorescence of Eu3+ was enhanced through antenna effect (AE), while the green fluorescence of MPA-Cu NCs was quenched through internal filter effect (IFE), leading to an obvious fluorescence color evolution from green to red for the probe solution. In addition to successful design of a smartphone-assisted colorimetric analysis platform for portable detection, a logic gate device capable of intelligently monitoring TC concentration is also designed.


Asunto(s)
Europio , Tetraciclinas , Europio/química , Cobre/análisis , Colorantes Fluorescentes/química , Antibacterianos/análisis , Tetraciclina , Espectrometría de Fluorescencia/métodos
5.
Food Chem ; 398: 133884, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35964575

RESUMEN

Development of selective and sensitive methods for the detection of 2, 6-dipicolinic acid (DPA), a biomarker produced by bacterial spores, is of great significance for maintaining public health and food safety. Herein, a ratiometric fluorescence strategy using graphene carbon nitride (g-C3N4) coupled with Eu3+ is designed for the assay of DPA. As the concentration of DPA increases, the emission intensity of g-C3N4 kept constant which acted as a stable internal reference, while the fluorescence of Eu3+ was enhanced obviously due to the antenna effect. The linear calibration ranged from 0.1 to 15 µM with a detection limit of 13 nM was obtained. More Importantly, a paper-based sensor with a smartphone was successfully combined to perform colorimetric and visual detection of DPA in situ. This method has good performance for the detection of DPA, which is expected to broaden the application prospects of preliminary biomarker monitoring.


Asunto(s)
Carbunco , Carbunco/diagnóstico , Carbunco/microbiología , Biomarcadores , Europio , Colorantes Fluorescentes , Humanos , Nitrilos , Ácidos Picolínicos , Teléfono Inteligente
6.
Front Plant Sci ; 13: 832559, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35615142

RESUMEN

Characterizing genetic diversity and structure and identifying conservation units are both crucial for the conservation and management of threatened species. The development of high-throughput sequencing technology provides exciting opportunities for conservation genetics. Here, we employed the powerful SuperGBS method to identify 33, 758 high-quality single-nucleotide polymorphisms (SNP) from 134 individuals of a critically endangered montane shrub endemic to North China, Lonicera oblata. A low level of genetic diversity and a high degree of genetic differentiation among populations were observed based on the SNP data. Both principal component and phylogenetic analyses detected seven clusters, which correspond exactly to the seven geographic populations. Under the optimal K = 7, Admixture suggested the combination of the two small and geographically neighboring populations in the Taihang Mountains, Dongling Mountains, and Lijiazhuang, while the division of the big population of Jiankou Great Wall in the Yan Mountains into two clusters. High population genetic diversity and a large number of private alleles were detected in the four large populations, while low diversity and non-private alleles were observed for the remaining three small populations, implying the importance of these large populations as conservation units in priority. Demographic history inference suggested two drastic contractions of population size events that occurred after the Middle Pleistocene Transition and the Last Glacial Maximum, respectively. Combining our previous ecological niche modeling results with the present genomic data, there was a possible presence of glacial refugia in the Taihang and Yan Mountains, North China. This study provides valuable data for the conservation and management of L. oblata and broadens the understanding of the high biodiversity in the Taihang and Yan Mountains.

7.
BMC Plant Biol ; 22(1): 80, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35193519

RESUMEN

BACKGROUND: Plants in cliff habitats may evolve specific reproductive strategies to cope with harsh environments, and unraveling these reproductive characteristics can improve our understanding of survival strategies and lithophyte evolution. This understanding is especially important for efforts to protect rare and endemic plants. Here, we investigated the reproductive biology of Lonicera oblata, an endangered lithophytic shrub that is scattered in highly fragmented and isolated cliff habitats of the Taihang and Yan mountains in North China. RESULTS: Flowers of L. oblata are herkogamous and protandrous, characteristics that can prevent autogamy at the single-flower level, and insects are necessary for pollination. The outcrossing index, pollen/ovule ratio, and the results of hand pollination were measured and all revealed a mixed mating system for L. oblata, that combines cross-fertilization and partial self-fertilization. The floral traits of L. oblata of zygomorphic and brightly yellowish corolla, heavy fragrance, and rich nectar, suggest an entomophilous pollination system. Sweat bees were observed as the most effective pollinators but their visiting frequencies were not high. Pollen limitation may limit the reproductive success of L. oblata. CONCLUSIONS: We determined the reproductive characteristics of L. oblata, a critically endangered species endemic to cliffs in North China, providing insight into its endangerment and suggesting conservation strategies. L. oblata has highly pollinator-dependent self-fertilization as part of a mixed mating system. Floral features such as low-flowering synchrony, asynchronous anthers dehiscence, and high duration of stigma receptivity, improve pollination efficiency in the case of low pollinator service. Our work provides reference information to understand the survival strategies and conservation of L. oblata and other lithophytes.


Asunto(s)
Flores/fisiología , Insectos , Lonicera/crecimiento & desarrollo , Animales , Tamaño Corporal , China , Conservación de los Recursos Naturales/métodos , Ecosistema , Especies en Peligro de Extinción , Flores/anatomía & histología , Lonicera/fisiología , Néctar de las Plantas , Polen/fisiología , Polinización
8.
Mitochondrial DNA B Resour ; 6(7): 1796-1798, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34377783

RESUMEN

The genus Lonicera (Caprifoliaceae) is of great economical significance. It has been taxonomically studied frequently in history, while phylogenetic relationships intra the genus are still obscure. Here, we reported the first species complete chloroplast genome sequence in the section Isoxylosteum, Lonicera angustifolia var. myrtillus. It is 156,222 bp in length, comprising a large single-copy (LSC) region of 89,838 bp, a small single-copy (SSC) region of 19,211 bp, and a pair of inverted repeats (IRs) of 23,509 bp. In L. angustifolia var. myrtillus chloroplast genome, a total of 114 functional genes were identified, with an overall GC content of 38.4%. The phylogenetic relationships of Lonicera based on maximum-likelihood (ML) showed that L. angustifolia var. myrtillus is most closely related to L. nervosa in section Isika. Our study contributes to the molecular phylogenetic studies of Lonicera and Caprifoliaceae.

9.
J Phys Chem Lett ; 11(12): 4644-4648, 2020 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-32452683

RESUMEN

Despite thermodynamic feasibility, the high activation energy originating from potential barriers and trap states kinetically prevents the interfacial transfer of electrons from semiconductor nanostructures to reduction cocatalysts, resulting in a lowered utilization of photogenerated charge carriers in photocatalysis. Nanostructuring-induced narrowing of potential barriers offers a rational solution to kinetically facilitate interfacial electron transfer by tunneling. Here, inspired by theoretical simulation, we manage to promote the separation of photogenerated charge carriers by coating the semiconductor nanostructures with a homogeneous interlayer. The low activation energy for interfacial electron transfer endows photocatalysis with nearly constant quantum yields and a quasi-first-order reaction to the incident photons and grants evident superiority over the photocatalyst without interlayers, especially under sunlight. In our demonstrated sunlight-driven hydrogen evolution integrated with benzylamine oxidation, the production rates for both reduction and oxidation half-reactions reach as high as ∼0.77 mmol dm-2 h-1, which are ∼10 times higher than that without an interlayer.

10.
J Phys Chem Lett ; 11(6): 2369-2373, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-32134664

RESUMEN

In photocatalytic reactions, the interfacial transfer of electrons from semiconductor nanostructures to cocatalysts is the key step that determines the utilization of photogenerated charges and is sensitively influenced by the behaviors of this electronic process. Under weak illumination, photocatalytic reaction rates deviate from linearity to incident light intensity (r = kss·Pincα, with α → 0.5), because charge recombination predominates interfacial transfer. When the irradiation intensity is high, theoretically, thermionic emission would be the major electronic process (r = kte·Pincα, with α → 2). The ratio of photocatalytic reaction rate to incident light intensity that mainly reflects the energy utilization would encounter a minimum along the variation of irradiation intensity. This crucial relationship, however, has hardly been consciously considered. In this work, inspired by theoretical simulation, we demonstrate that sunlight-driven photocatalysis is generally on the bottom of the energy utilization curves for certain common semiconductors (CdS, TiO2, or C3N4).

11.
Mitochondrial DNA B Resour ; 4(2): 2337-2338, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-33365532

RESUMEN

Lonicera oblata, a critically endangered species endemic to North China with about 30 wild individuals, has long been ignored for conservation since its publication because of little attention on its living situation. In this study, we characterized the complete chloroplast (cp) genome of L. oblata. The cp genome was 155,481 bp in length, included a large single-copy (LSC) region of 89,139 bp, a small single-copy (SSC) region of 18,676 bp, and two inverted repeat (IR) regions of 23,833 bp each. The genome contains 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. Phylogenetic position of L. oblata was also investigated based on cp genome phylogeny of Lonicera representatives. This study is valuable for molecular phylogenetic study and conservation of Lonicera and related taxa.

12.
Mitochondrial DNA B Resour ; 4(2): 3173-3174, 2019 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-33365905

RESUMEN

Symphoricarpos orbiculatus is an important landscape and ornamental plant. In this study, we report the complete chloroplast genome sequences of S. orbiculatus. The complete chloroplast genome of S. orbiculatus was 156,044 bp in length. The genome has a typical quadripartite structure, including a large single-copy (LSC) region of 88,756 bp, a small single-copy (SSC) region of 19,130 bp, and two inverted repeat (IR) regions of 24,079 bp each. Overall, the GC content was 38.4%. In the genome, it was identified to comprise130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. This study provides valuable information for molecular phylogenetic study of Caprifoliaceae and is significant for variety development of Symphoricarpos.

13.
Oxid Med Cell Longev ; 2018: 9501427, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30327715

RESUMEN

Major depressive disorder (MDD) is a chronic mental disease that adversely affects human mood and cognition. Many first-line antidepressant drugs have high rates of partial responsiveness or nonresponsiveness with side effects, and finding more effective drugs for the treatment of depression is therefore urgently needed. THSG, a main active compound of the traditional Chinese herb Polygonum multiflorum, reportedly acts as a neuroprotective agent. This study aimed to illustrate whether THSG prevents depressive-like behaviors induced by chronic restraint stress (CRS) in an MDD mouse model. Our results demonstrated that the peripheral administration of different THSG doses (10 mg/kg, 20 mg/kg, and 40 mg/kg) reversed the depressive-like behaviors in CRS mice as measured by the tail suspension test, forced swimming test, and open-field test. Further analyses suggested that THSG treatment reduced oxidative stress in both the central and peripheral nervous systems of CRS mice. In addition, heightened inflammatory responses, demonstrated by the increased expression of proinflammatory factors (TNF-α, IL-1ß, and IL-6), in hippocampal and prefrontal cortex tissues of CRS mice were inhibited by THSG administration. THSG also restored the diminished Akt signaling pathway in the brains of CRS mice. Moreover, our data suggest increased astrocyte proliferation and neurogenesis in the hippocampus of CRS mice after THSG treatment. Taken together, our results demonstrated an antidepressant effect of THSG in a mouse model of MDD for the first time, and oxidative stress and inflammatory pathways were determined to play roles in this effect.


Asunto(s)
Depresión/fisiopatología , Glucósidos/farmacología , Hipocampo/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Estilbenos/farmacología , Animales , Antidepresivos/farmacología , Depresión/psicología , Modelos Animales de Enfermedad , Fallopia multiflora , Hipocampo/fisiopatología , Inflamación/fisiopatología , Inflamación/psicología , Masculino , Ratones , Ratones Endogámicos C57BL , Restricción Física/efectos adversos , Restricción Física/psicología , Transducción de Señal/efectos de los fármacos , Estrés Psicológico/psicología
14.
PLoS One ; 8(8): e73700, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24014103

RESUMEN

BACKGROUND AND OBJECTIVES: Disruption of apoptosis has been implicated in carcinogenesis. Specifically, various single-nucleotide polymorphisms (SNPs) in apoptotic genes, such as FAS-1377 G/A SNP, have been associated with cancer risk. FAS-1377 G/A SNP has been shown to alter FAS gene promoter transcriptional activity. Down-regulation of FAS and cell death resistance is key to many cancers, but an association between FAS-1377 G/A SNP and cancer risk is uncertain. Therefore, we conducted a meta-analysis of the current literature to clarify this relationship. METHODOLOGY/PRINCIPAL FINDINGS: From PubMed and Chinese language (CNKI and WanFang) databases, we located articles published up to March 5, 2013, obtaining 44 case-control studies from 41 different articles containing 17,858 cases and 24,311 controls based on search criteria for cancer susceptibility related to the FAS gene -1377 G/A SNP. Odds ratios (ORs) and 95% confidence intervals (CI) revealed association strengths. Data show that the -1377 G allele was protective against cancer risk. Similar associations were detected in "source of control," ethnicity and cancer type subgroups. Lower cancer risk was found in both smokers with a GG+GA genotype and in non-smokers with the GG+GA genotype, when compared to smokers and nonsmokers with the AA genotype. Males carrying the -1377G allele (GG+GA) had lower cancer incidence than those with the AA genotype. Individuals who carried both FAS-1377(GG+GA)/FASL-844(TT+TC) genotypes appeared to have lower risk of cancer than those who carried both FAS-1377 AA/FASL-844 CC genotypes. CONCLUSIONS/SIGNIFICANCE: The FAS-1377 G/A SNP may decrease cancer risk. Studies with larger samples to study gene-environment interactions are warranted to understand the role of FAS gene polymorphisms, especially -1377 G/A SNP, in cancer risk.


Asunto(s)
Alelos , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas/genética , Transcripción Genética/genética , Receptor fas/genética , Femenino , Interacción Gen-Ambiente , Genotipo , Humanos , Masculino , Neoplasias/epidemiología , PubMed , Factores de Riesgo
16.
DNA Cell Biol ; 31(5): 772-6, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22047080

RESUMEN

Matrix metalloproteinase-7 (MMP-7) is a small secreted proteolytic enzyme with broad substrate specificity. Its expression is associated with tumor invasion, metastasis, and survival for a number of cancers. However, data from published studies with individually low statistical power are conflicting. Here, we performed a meta-analysis of 14 publications (16 case-control studies) to better assess the purported relationship. Eligible studies were identified by searching the Pubmed database. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association. Overall, we found that the -181 G allele increased cancer risk in East Asians (G-allele vs. A-allele, OR=1.35, 95% CI: 1.25-1.46, P(heterogeneity)=0.01; GA vs. AA, OR=1.40, 95% CI: 1.16-1.69, P(heterogeneity)=0.04; GG+GA vs. AA, OR=1.52, 95% CI: 1.30-1.78, P(heterogeneity)=0.00). Similarly, in the stratified analysis by cancer type and source of control, significantly increased cancer risk was indicated. Our study showed evidence that MMP7 -181A/G polymorphism may increase cancer risk in the East Asian population. Future studies with larger sample size are warranted to further evaluate this association in greater detail.


Asunto(s)
Metaloproteinasa 7 de la Matriz/genética , Neoplasias/genética , Polimorfismo Genético/genética , Estudios de Casos y Controles , Asia Oriental/epidemiología , Genotipo , Humanos , Metaanálisis como Asunto , Neoplasias/epidemiología , Pronóstico , Factores de Riesgo
17.
J Nutr Biochem ; 13(11): 653-663, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12550062

RESUMEN

This study investigated the supplementation with vitamin C or/and E on the antioxidant system in hemodialysis patients. Thirty-eight hemodialysis patients (27 males and 11 females) with the average of 60 years old were divided into four groups: placebo (400 mg starch/time), vitamin C (400 mg/time)-, vitamin E (400 mg d,l- alpha-tocopheryl acetate/time)-, and vitamin C (400 mg/time) + E (400 mg d,l- alpha-tocopheryl acetate/time)-supplemented groups for 6-week supplementation. The patients orally received three capsules of placebo or antioxidant(s) three times a week after finishing hemodialysis. Thirty-six healthy subjects (22 males and 14 females) with the average of 58 years old were recruited as the control group. Hemodialysis patients significantly decreased plasma vitamin C by 32%, erythrocyte glutathione by 26%, and plasma total antioxidant status by 9%, but increased plasma lipid peroxide levels by 102% compared with the control group at the baseline. The levels of plasma vitamin C and total antioxidant status significantly decreased by 24% and 18%, respectively, from the post-dialysate compared with those from the pre-dialysate. At week 6, vitamin C + E-supplemented group significantly increased plasma vitamin C and E, erythrocyte glutathione, and plasma antioxidant status, and inhibited plasma lipid peroxides compared with placebo group. Additionally, vitamin C + E-supplemented group had higher plasma vitamin C, vitamin E, and total antioxidant status, and lower plasma lipid peroxides than placebo group even at least 2 weeks after the termination of the supplements. Therefore, antioxidant vitamin supplements could improve antioxidant status and decrease lipid peroxides of hemodialysis patients.

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