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1.
Biomol NMR Assign ; 17(2): 159-165, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37162737

RESUMEN

Functional bacterial amyloids provide structural scaffolding to bacterial biofilms. In contrast to the pathological amyloids, they have a role in vivo and are tightly regulated. Their presence is essential to the integrity of the bacterial communities surviving in biofilms and may cause serious health complications. Targeting amyloids in biofilms could be a novel approach to prevent chronic infections. However, structural information is very scarce on them in both soluble monomeric and insoluble fibrillar forms, hindering our molecular understanding and strategies to fight biofilm related diseases. Here, we present solution-state NMR assignment of 250 amino acid long biofilm-forming functional-amyloid FapC from Pseudomonas aeruginosa. We studied full-length (FL) and shorter minimalistic-truncated (L2R3C) FapC constructs without the signal-sequence that is required for secretion. 91% and 100% backbone NH resonance assignments for FL and L2R3C constructs, respectively, indicate that soluble monomeric FapC is predominantly disordered, with sizeable secondary structural propensities mostly as PP2 helices, but also as α-helices and ß-sheets highlighting hotspots for fibrillation initiation interface. A shorter construct showing almost identical NMR chemical shifts highlights the promise of utilizing it for more demanding solid-state NMR studies that require methods to alleviate signal redundancy due to almost identical repeat units. This study provides key NMR resonance assignments for future structural studies of soluble, pre-fibrillar and fibrillar forms of FapC.


Asunto(s)
Amiloide , Pseudomonas aeruginosa , Pseudomonas aeruginosa/metabolismo , Resonancia Magnética Nuclear Biomolecular , Amiloide/química , Proteínas Amiloidogénicas/química , Proteínas Amiloidogénicas/metabolismo , Biopelículas
2.
Front Chem ; 10: 941065, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35910728

RESUMEN

Spinal cord injury (SCI) is a devastating and common neurological disorder that is difficult to treat. The pain can sustain for many years, making the sufferer extremely painful. Nerve stimulation was first reported half a century ago as a treatment for neuropathic pain. Since then, the method of electrical stimulation through leads placed in the epidural space on the dorsal side of the spinal cord has become a valuable therapeutic tool for SCI. But nerve stimulation equipment is expensive, and the stimulator design and treatment plan are complicated, which hinders its development. In recent years, wearable and implantable triboelectric nanogenerators (TENGs) developed rapidly, and their low cost and safety have brought a new turning point for the development of nerve stimulation. Nanofibrous membrane has been proved that it is a flexible material with the advantages of ultrathin diameter, good connectivity, easy scale-up, tunable wettability, fine flexibility, tunable porosity, controllable composition and so on. In this paper, we discuss the technology of using nanofiber membrane on clothing to create TENGs to provide continuous electrical energy for nerve stimulation to treat SCI in patients by analyzing previous research.

3.
Cancers (Basel) ; 14(16)2022 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-36010913

RESUMEN

Background: As there are no randomized trials comparing twice-daily with sequential hypofractionated (sequential hypo) radiotherapy regimens for limited-stage small-cell lung cancer (LS-SCLC). This study aimed to compare these two regimens for LS-SCLC by propensity score-matched analysis (PSM). Methods: We retrospectively analyzed 108 LS-SCLC patients between January 2015 and July 2019. All patients received concurrent twice-daily or sequential hypo radiotherapy. The survival, failure patterns, and toxicities were evaluated before and after PSM. Results: Before PSM, multivariate analysis showed that patients treated with sequential hypo had a significantly better overall survival (OS) and distant metastasis-free survival (DMFS) (HR = 0.353, p = 0.009; HR = 0.483, p = 0.039, respectively). Total radiotherapy time ≥ 24 days and stage III (HR = 2.454, p = 0.004; HR = 2.310, p = 0.004, respectively) were poor prognostic indicators for OS. Patients with a total radiotherapy time ≥ 24 days and N2−3 were more likely to recur than others (HR = 1.774, p = 0.048; HR = 2.369, p = 0.047, respectively). N2−3 (HR = 3.032, p = 0.011) was a poor prognostic indicator for DMFS. After PSM, being aged ≥65 years was associated with poorer OS, relapse-free survival (RFS) and DMFS (p < 0.05). A total radiotherapy time of ≥24 days was a poor prognostic indicator for OS and RFS (HR = 2.671, p = 0.046; HR = 2.370, p = 0.054, respectively). Although there was no significant difference, the patients in the sequential hypo group had a trend towards a better OS. The failure pattern between the two groups showed no difference. More patients had grade 1−2 esophagitis in the twice-daily group (p = 0.001). Conclusions: After propensity matching, no difference was shown in survival and failure. The sequential hypo schedule was associated with comparable survival and less toxicity and may be used as an alternative to concurrent twice-daily regimens.

4.
Nano Lett ; 21(18): 7845-7854, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34505789

RESUMEN

The photovoltaic performance of inorganic perovskite solar cells (PSCs) still lags behind the organic-inorganic hybrid PSCs due to limited light absorption of wide bandgap CsPbI3-xBrx under solar illumination. Constructing tandem devices with organic solar cells can effectively extend light absorption toward the long-wavelength region and reduce radiative photovoltage loss. Herein, we utilize wide-bandgap CsPbI2Br semiconductor and narrow-bandgap PM6:Y6-BO blend to fabricate perovskite/organic tandem solar cells with an efficiency of 21.1% and a very small tandem open-circuit voltage loss of 0.06 V. We demonstrate that the hole transport material of the interconnecting layers plays a critical role in determining efficiency, with polyTPD being superior to PBDB-T-Si and D18 due to its low parasitic absorption, sufficient hole mobility and quasi-Ohmic contact to suppress charge accumulation and voltage loss within the tandem device. These perovskite/organic tandem devices also display superior storage, thermal and ultraviolet stabilities.

5.
J Cell Biol ; 220(8)2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34081091

RESUMEN

The step-by-step process of chromosome segregation defines the stages of the cell cycle. In eukaryotes, signals controlling these steps converge upon the kinetochore, a multiprotein assembly that connects spindle microtubules to chromosomal centromeres. Kinetochores control and adapt to major chromosomal transactions, including replication of centromeric DNA, biorientation of sister centromeres on the metaphase spindle, and transit of sister chromatids into daughter cells during anaphase. Although the mechanisms that ensure tight microtubule coupling at anaphase are at least partly understood, kinetochore adaptations that support other cell cycle transitions are not. We report here a mechanism that enables regulated control of kinetochore sumoylation. A conserved surface of the Ctf3/CENP-I kinetochore protein provides a binding site for Ulp2, the nuclear enzyme that removes SUMO chains from modified substrates. Ctf3 mutations that disable Ulp2 recruitment cause elevated inner kinetochore sumoylation and defective chromosome segregation. The location of the site within the assembled kinetochore suggests coordination between sumoylation and other cell cycle-regulated processes.


Asunto(s)
Segregación Cromosómica , Cromosomas Fúngicos , Endopeptidasas/metabolismo , Cinetocoros/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , Microscopía por Crioelectrón , Endopeptidasas/química , Endopeptidasas/genética , Microscopía Fluorescente , Modelos Moleculares , Mutación , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Sumoilación
6.
PLoS One ; 16(2): e0247132, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33600463

RESUMEN

Protein sumoylation, especially when catalyzed by the Mms21 SUMO E3 ligase, plays a major role in suppressing duplication-mediated gross chromosomal rearrangements (dGCRs). How Mms21 targets its substrates in the cell is insufficiently understood. Here, we demonstrate that Esc2, a protein with SUMO-like domains (SLDs), recruits the Ubc9 SUMO conjugating enzyme to specifically facilitate Mms21-dependent sumoylation and suppress dGCRs. The D430R mutation in Esc2 impairs its binding to Ubc9 and causes a synergistic growth defect and accumulation of dGCRs with mutations that delete the Siz1 and Siz2 E3 ligases. By contrast, esc2-D430R does not appreciably affect sensitivity to DNA damage or the dGCRs caused by the catalytically inactive mms21-CH. Moreover, proteome-wide analysis of intracellular sumoylation demonstrates that esc2-D430R specifically down-regulates sumoylation levels of Mms21-preferred targets, including the nucleolar proteins, components of the SMC complexes and the MCM complex that acts as the catalytic core of the replicative DNA helicase. These effects closely resemble those caused by mms21-CH, and are relatively unaffected by deleting Siz1 and Siz2. Thus, by recruiting Ubc9, Esc2 facilitates Mms21-dependent sumoylation to suppress the accumulation of dGCRs independent of Siz1 and Siz2.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Proteína SUMO-1/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Secuencia de Aminoácidos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Daño del ADN , Replicación del ADN , Regulación hacia Abajo , Mutagénesis , Unión Proteica , Dominios Proteicos , Estabilidad Proteica , Proteómica , Proteína SUMO-1/química , Proteína SUMO-1/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Alineación de Secuencia , Sumoilación , Enzimas Ubiquitina-Conjugadoras/química , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
7.
Neural Regen Res ; 16(9): 1829-1835, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33510090

RESUMEN

The study illustrates that graphene oxide nanosheets can endow materials with continuous electrical conductivity for up to 4 weeks. Conductive nerve scaffolds can bridge a sciatic nerve injury and guide the growth of neurons; however, whether the scaffolds can be used for the repair of spinal cord nerve injuries remains to be explored. In this study, a conductive graphene oxide composited chitosan scaffold was fabricated by genipin crosslinking and lyophilization. The prepared chitosan-graphene oxide scaffold presented a porous structure with an inner diameter of 18-87 µm, and a conductivity that reached 2.83 mS/cm because of good distribution of the graphene oxide nanosheets, which could be degraded by peroxidase. The chitosan-graphene oxide scaffold was transplanted into a T9 total resected rat spinal cord. The results show that the chitosan-graphene oxide scaffold induces nerve cells to grow into the pores between chitosan molecular chains, inducing angiogenesis in regenerated tissue, and promote neuron migration and neural tissue regeneration in the pores of the scaffold, thereby promoting the repair of damaged nerve tissue. The behavioral and electrophysiological results suggest that the chitosan-graphene oxide scaffold could significantly restore the neurological function of rats. Moreover, the functional recovery of rats treated with chitosan-graphene oxide scaffold was better than that treated with chitosan scaffold. The results show that graphene oxide could have a positive role in the recovery of neurological function after spinal cord injury by promoting the degradation of the scaffold, adhesion, and migration of nerve cells to the scaffold. This study was approved by the Ethics Committee of Animal Research at the First Affiliated Hospital of Third Military Medical University (Army Medical University) (approval No. AMUWEC20191327) on August 30, 2019.

8.
Adv Sci (Weinh) ; 7(21): 2000421, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33173723

RESUMEN

Inorganic perovskite solar cells (PSCs) have witnessed great progress in recent years due to their superior thermal stability. As a representative, CsPbI2Br is attracting considerable attention as it can balance the high efficiency of CsPbI3 and the stability of CsPbBr3. However, most research employs doped charge transport materials or applies bilayer transport layers to obtain decent performance, which vastly complicates the fabrication process and scarcely satisfies the commercial production requirement. In this work, all-layer-doping-free inorganic CsPbI2Br PSCs using organic ligands armored ZnO as the electron transport materials achieve an encouraging performance of 16.84%, which is one of the highest efficiencies among published works. Meanwhile, both the ZnO-based CsPbI2Br film and device show superior photostability under continuous white light-emitting diode illumination and improved thermal stability under 85 °C. The remarkable enhanced performance arises from the favorable organic ligands (acetate ions) residue in the ZnO film, which not only can conduce to maintain high crystallinity of perovskite, but also passivate traps at the interface through cesium/acetate interactions, thus suppressing the photo- and thermal- induced perovskite degradation.

9.
Biomed J ; 43(4): 318-324, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32654885

RESUMEN

Aggressive tracing of contacts of confirmed cases is crucial to Taiwan's successful control of the early spread of COVID-19. As the pandemic lingers, an epidemiological investigation that can be conducted efficiently in a timely manner can help decrease the burden on the health personnel and increase the usefulness of such information in decision making. To develop a new tool that can improve the current practice of epidemiological investigation by incorporating new technologies in digital platform and knowledge graphs. To meet the various needs of the epidemiological investigation, we decided to develop an e-Outbreak Platform that provides a semi-structured, multifaceted, computer-aided questionnaire for outbreak investigation. There are three major parts of the platform: (1) a graphic portal that allows users to have an at-glance grasp of the functions provided by the platform and then choose the one they need; (2) disease-specific questionnaires that can accommodate different formats of the information, including text typing, button selection, and pull-down menu; and (3) functions to utilize the stored information, including report generation, statistical analyses, and knowledge graphs displaying contact tracing. When the number of outbreak investigation increases, the knowledge graphs can be extended to encompass other persons appearing in the same location at the same time, i.e., constituting a potential contact cluster. The information extracted can also be used to display the tracing on a map in animation. Overall, this system can provide a basis for further refinement that can be generalized to a variety of outbreak investigations.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/diagnóstico , Brotes de Enfermedades/prevención & control , Neumonía Viral/diagnóstico , Encuestas y Cuestionarios , COVID-19 , Femenino , Humanos , Masculino , Pandemias , SARS-CoV-2 , Taiwán
10.
ACS Appl Mater Interfaces ; 11(46): 43452-43459, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31659892

RESUMEN

Two-dimensional (2D)/three-dimensional (3D) perovskites have been successfully applied in high-efficiency light-emitting diodes (LEDs) because of their large exciton binding energy (Eb) caused by the quantum and dielectric confinements. Thermal annealing and antisolvent treatments are usually executed in order to promote the crystallization and film quality of perovskites, which add complexity to the device fabrication process. Here, the cesium-based 2D/3D perovskite was prepared by introducing ammonium halide benzamidine hydrochloride (BMCl) as the additive. By further introducing an appropriate amount of MABr and PbBr2, BM2(Cs1-xMAxPbBr3)n-1PbBr4 crystals can be formed rapidly without any additional treatments, while inhibiting the formation of the unfavorable Cs4PbBr6 phase. The optimized 2D/3D perovskite-based LEDs achieved a maximum luminance of 12 367 Cd/m2, a current efficiency of 17.4 Cd/A, and an external quantum efficiency of 5.2%. Our results suggest that appropriate perovskite crystallization can be achieved at room temperature by the regulation of precursor solution, making the perovskite crystallization process easier to control with reduced processing complexity.

11.
ACS Appl Mater Interfaces ; 11(41): 37833-37841, 2019 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-31538760

RESUMEN

Perovskite solar cells (PSCs) have demonstrated encouraging progress in recent years. Additive engineering, where diverse additives are incorporated into the perovskite layer, has been widely adopted to tune the perovskite grains, reduce defect density and charge recombination. Here, we observe a universal phenomenon that organic chloride additives enhance the open circuit voltage (VOC) and power conversion efficiencies (PCEs) of direct PSCs but decrease the VOC, short-circuit current (JSC), and PCE of inverted PSCs, regardless of the choice of charge transport materials. The polyTPD-based direct device incorporating trimethylammonium chloride (TACl) additive delivery improved PCE from 17.8 to 20.0%, arising from the enhanced VOC from 1.03 to 1.12 V. With the same content of TACl, the best PCE of the polyTPD-based inverted device decreased from 20.2 to 18.5% because of the reduced VOC (1.05-1.01 V) and JSC (23.2-22.5 mA/cm2). Our investigation confirms that organic chloride will p-dope perovskites and elevate the work functions, which lead to favorable/unfavorable charge transfer between perovskite films and its upper transport layers in direct and inverted devices. This work provides an insight into the rational design of the device structure when applying additives which can dope the perovskite to affect charge transfer at the perovskite/charge transport layer interface.

12.
Nucleic Acids Res ; 47(10): 5126-5140, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-30916331

RESUMEN

RecA is essential to recombinational DNA repair in which RecA filaments mediate the homologous DNA pairing and strand exchange. Both RecA filament assembly and the subsequent DNA strand exchange are directional. Here, we demonstrate that the polarity of DNA strand exchange is embedded within RecA filaments even in the absence of ATP hydrolysis, at least over short DNA segments. Using single-molecule tethered particle motion, we show that successful strand exchange in the presence of ATP proceeds with a 5'-to-3' polarity, as demonstrated previously. RecA filaments prepared with ATPγS also exhibit a 5'-to-3' progress of strand exchange, suggesting that the polarity is not determined by RecA disassembly and/or ATP hydrolysis. RecAΔC17 mutants, lacking a C-terminal autoregulatory flap, also promote strand exchange in a 5'-to-3' polarity in ATPγS, a polarity that is largely lost with this RecA variant when ATP is hydrolyzed. We propose that there is an inherent strand exchange polarity mediated by the structure of the RecA filament groove, associated by conformation changes propagated in a polar manner as DNA is progressively exchanged. ATP hydrolysis is coupled to polar strand exchange over longer distances, and its contribution to the polarity requires an intact RecA C-terminus.


Asunto(s)
Adenosina Trifosfato/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Rec A Recombinasas/metabolismo , Adenosina Trifosfato/análogos & derivados , ADN Bacteriano/genética , ADN de Cadena Simple , Escherichia coli/metabolismo , Hidrólisis , Iones , Cinética , Magnesio/química , Nucleoproteínas/metabolismo , Dominios Proteicos
13.
ACS Appl Mater Interfaces ; 10(39): 33144-33152, 2018 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-30192502

RESUMEN

Stability remains as a challenge of perovskite solar cells although encouraging progress has been made toward their maximum achievable power conversion efficiency in recent years. Light-soaking issue, where the device performance improves upon continuous light illumination and reduces upon storage in dark, is widely observed and marked as the early-stage instability during device operation. In this work, we have employed conjugated polymer PCDTBT as the dopant-free hole-transport layer to fabricate devices without hysteresis but with reversible light-soaking instability. The introduction of n-type molecules, either organic molecule PDI2 or fullerene derivative PC61BM, as the interfacial layer between TiO2 and perovskite layers can effectively reduce or eliminate this instability owing to the efficient charge transport and defect passivation at the electron-transport layer interface, accompanied with an efficiency of 15.7 and 17.7%, respectively. We conclude that the light-soaking instability of these perovskite solar cells is mainly originated from the charge accumulation at the TiO2/perovskite interface and can be eliminated once the interfacial charge can be suppressed by interfacial modifications to improve charge transport at the interface.

14.
J Agric Food Chem ; 60(29): 7229-37, 2012 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-22676798

RESUMEN

Manuka honey from New Zealand is often considered to be a medicinal product of special value due to its high level of antimicrobial activity. Therefore, the distinct authentication of its botanical origin is of great importance. Aside from the common pollen analysis, it is in this respect particularly the analysis of the phenolic acids, flavonoids, and norisoprenoids that is described as useful. In the present study, numerous manuka honeys were analyzed by UPLC-PDA-MS/MS after solid-phase extraction and compared to other kinds of honey to define marker substances characteristic for manuka honeys. The PDA profiles obtained differed markedly from each other so that the individual honey samples could be assigned to three groups. For the honeys of group 1 the comparably high concentrations of 4-hydroxybenzoic acid, dehydrovomifoliol, and benzoic acid proved to be typical, whereas the profiles of group 2 showed high kojic acid and 2-methoxybenzoic acid intensities. The manuka honeys of group 3, on the other hand, yielded high amounts of syringic acid, 4-methoxyphenyllactic acid, and methyl syringate. Furthermore, the comprehensive comparison of manuka honeys to other unifloral honeys revealed that especially kojic acid, 5-methyl-3-furancarboxylic acid, leptosin, unedone, 2-methoxybenzoic acid, 4-methoxyphenyllactic acid, 3-hydroxy-1-(2-methoxyphenyl)penta-1,4-dione, and methyl syringate were useful for distinguishing manuka honeys from the other kinds of investigated honeys. Moreover, kojic acid, unedone, 5-methyl-3-furancarboxylic acid, 3-hydroxy-1-(2-methoxyphenyl)penta-1,4-dione, and lumichrome were identified in manuka honey for the first time.


Asunto(s)
Miel/análisis , Miel/clasificación , Leptospermum , Fenoles/análisis , Piruvaldehído/análisis , Cromatografía Líquida de Alta Presión , Flavonoides/análisis , Flores , Nueva Zelanda , Norisoprenoides/análisis , Extracción en Fase Sólida , Espectrometría de Masas en Tándem
15.
Inorg Chem ; 51(9): 5164-72, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22486213

RESUMEN

Investigations are performed on low-temperature oxygen diffusion in the carbon vacancy ordered ZrC(0.6)and thus induced formation of the oxygen atom ordered ZrC(0.6)O(0.4). Theoretically, a superstructure of Zr(2)CO can be constructed via the complete substitution of carbon vacancies with O atoms in the Zr(2)C model. In the ordered ZrC(0.6), the consecutive arrangement of vacancies forms the vacancy channels along some zone axes in the C sublattice. Through these vacancy channels, the thermally activated oxygen diffusion is significantly facilitated. The oxygen atoms diffuse directly into and occupy the vacancies, producing the ordered ZrC(0.6)O(0.4). Relative to the ordered ZrC(0.6), the Zr positions are finely tuned in the ordered ZrC(0.6)O(0.4) because of the ionic Zr-O bonds. Because of this fine adjustment of Zr positions and the presence of oxygen atoms, the superstructural reflections are always observable in a selected area electron diffraction (SAED) pattern, despite the invisibility of superstructural reflections in ZrC(0.6) along some special zone axes. Similar to the vacancies in ordered ZrC(0.6), the ordering arrangement of O atoms in the ordered ZrC(0.6)O(0.4) is in nanoscale length, thus forming the nano superstructural domains with irregular shapes.

16.
Zhen Ci Yan Jiu ; 36(4): 278-87, 2011 Aug.
Artículo en Chino | MEDLINE | ID: mdl-21942182

RESUMEN

OBJECTIVE: To observe the effect of acupuncture of Zusanli (ST 36) on electroencephalogram (EEG) so as to probe into its law in regulating the interconnectivity of brain functional network. METHODS: A total of 9 healthy young volunteer students (6 male, 3 female) participated in the present study. They were asked to take a dorsal position on a test-bed. EEG signals were acquired from 22 surface scalp electrodes (Fp1, Fp2, F7, F3, F2, F4, F8, A1, T3, C3, C2, C4, T4, A2, T5, P3, P2, P4, T6, O2, O1 and O2) fixed on the subject's head. Acupuncture stimulation was applied to the right Zusanli (ST 36) by manipulating the filiform needle with uniform reducing-reinforcing method and at a frequency of about 50 cycles/min for 2 min. Then the stimulation was stopped for 10 min, and repeated once again (needle-twirling frequency: 150 and 200 cycles/min), 3 times altogether. The acquired EEG data were analyzed by using coherence estimation method, average path length, average clustering coefficient, and the average degree of the articulation points (nodes) for analyzing the synchronization of EEG signals before, during and after acupuncture. RESULTS: In comparison with pre-acupuncture, the coherence amplitude values of EEG-delta (1-4 Hz) and y (31-47 Hz) waves were increased significantly after acupuncture of ST 36. No significant changes were found in the amplitude values of EEG-theta (5-8 Hz), -alpha (9-13 Hz) and-beta (14-30 Hz) waves after acupuncture stimulation. During and after acupuncture, the synchronism values of EEG-delta waves of different leads and numbers of interconnectivity between every two brain functional regions in majority of the 9 volunteers were increased clearly. In all volunteers, the degree values of all nodes except A1 and A2, the average clustering coefficients along with the increase of the threshold (r), and the average path lengths of the brain functional network of EEG-delta waves during and after acupuncture were also increased evidently (the latter two items, P < 0.05), suggesting an increase of the information exchange and functional connectivity of different brain regions. CONCLUSION: Acupuncture of Zusanli (ST 36) can increase the amplitude and synchronization of EEG-delta waves of different leads, and potentiate the functional interconnectivity of brain functional network.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Encéfalo/fisiología , Red Nerviosa , Adulto , Electroencefalografía , Femenino , Humanos , Masculino
17.
Chem Biodivers ; 4(5): 893-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17510984

RESUMEN

The endophytic strain Mesorhizobium sp. CCNWGX022 was isolated from licorice (Glycyrrhiza uralensis Fisch.) grown in the arid and semi-arid regions of Northwest China. The new stearic acid derived gamma-lactone 1, named rhizobialide (= (5S)-4,5-dihydro-5-(8-oxotetradecyl)furan-2(3H)-one), was isolated from the petroleum-ether extract of the fermentation broth of this strain. The structure of 1 was elucidated on the basis of spectroscopic and mass-spectrometric analysis. This is the first report of this type of compound from rhizobia.


Asunto(s)
4-Butirolactona/análogos & derivados , Glycyrrhiza uralensis/microbiología , Rhizobium/química , Simbiosis , 4-Butirolactona/química , 4-Butirolactona/aislamiento & purificación , China , Lactonas/química , Lactonas/aislamiento & purificación , Ácidos Esteáricos/química , Ácidos Esteáricos/aislamiento & purificación
18.
Neuroscience Bulletin ; (6): 175-179, 2007.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-300980

RESUMEN

<p><b>OBJECTIVE</b>To examine the vesicular glutamate transporters (VGluTs: VGluT1-VGluT3) in the peripheral vestibular system.</p><p><b>METHODS</b>The vestibular structures, including Scarpa's ganglion (vestibular ganglion, VG), maculae of utricle and saccule, and ampullary cristae, from normal Sprague-Dawley rats were processed immunohistochemically for VGluTs, by avidin-biotinylated peroxidase complex method, with 3-3'-diaminobenzidine (DAB) as chromogen.</p><p><b>RESULTS</b>(1) VGluT1 was localized to partial neurons of VG and to the putative primary afferent fibers innervating vestibular end-organs. (2) Intense VGluT3 immunoreactivity was detected in large number of sensory epithelia cells, and weak labeling of VGluT3-positive afferent fibers was in the maculae and ampullary cristae. (3) No or very weak VGluT2 immunoreactivity was observed in the VG and acoustic maculae.</p><p><b>CONCLUSION</b>These results provide the morphological support that glutamate exists in the peripheral vestibular system, and it may play an important role in the centripetal vestibular transmission.</p>


Asunto(s)
Animales , Ratas , Máculas Acústicas , Metabolismo , Neuronas , Metabolismo , Ratas Sprague-Dawley , Proteínas de Transporte Vesicular de Glutamato , Clasificación , Metabolismo , Vestíbulo del Laberinto , Metabolismo , Nervio Vestibulococlear , Biología Celular , Metabolismo
19.
Neuroscience Bulletin ; (6): 204-208, 2006.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-300927

RESUMEN

Objective Aims to delineate the distribution profile of three isoforms of vesicular glutamate transporter (VGluT), viz. VGluT1-3, and their cellular localization within vestibular nuclear complex (VNC). Methods Brain sections from normal Sprague-Dawley rats were processed immunohistochemically for VGluT detection, employing avidin-biotinylated peroxidase complex method with 3-3'-diaminobenzidine (DAB) as chromogen. Results The whole VNC expressed all of the three transporters that were observed to be localized to the fiber endings. Compared with VGluT1 and VGluT3, VGluT2 demonstrated a relatively homogeneous distribution, with much higher density in VNC. VGluT3 displayed the highest density in lateral vestibular nucleus and group X, contrasting with the sparse immunostained puncta within vestibular medial and inferior nuclei. Conclusion Glutamtatergic pathways participate in the processing of vestibular signals within VNC mainly through the re-uptake of glutamate into synaptic vesicles by VGluT1 and 2, whereas VGluT3 may play a similar role mainly in areas other than medial and inferior nuclei of VNC.

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