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1.
Sensors (Basel) ; 24(11)2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38894420

RESUMEN

Active disturbance rejection control (ADRC) is widely used in airborne optoelectronic stabilization platforms due to its minimal reliance on the mathematical model of the controlled object. The extended state observer (ESO) is the core of ADRC, which treats internal parameter variations and external disturbances as total disturbances, observes the disturbances as extended states, and then compensates them into the control loop to eliminate their effects. However, the ESO can only achieve a precise estimation of constant or slowly varying disturbances. When the disturbance is periodically changing, satisfactory results cannot be obtained. In this paper, a generalized high-order extended state observer (GHOESO) is proposed to achieve the precise estimation of known frequency sinusoidal disturbance signals and improve disturbance suppression levels. Through numerical simulations, a traditional ESO and GHOESO are compared in terms of disturbance observation capability and disturbance suppression ability for single and compound disturbances based on our prior knowledge of disturbance frequency. The effectiveness of the proposed GHOESO method is verified. Finally, the algorithm is applied to an airborne optoelectronic stabilization platform for a 1°/1 Hz swing experiment on a space hexapod swing table. The experimental results demonstrate the superiority of the GHOESO proposed in this paper.

2.
BMC Cancer ; 23(1): 980, 2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37838670

RESUMEN

BACKGROUND: Aponermin, a circularly permuted tumor necrosis factor-related apoptosis-inducing ligand, is a potential death receptor 4/5-targeted antitumour candidate. Previous phase 1/2 studies have demonstrated the efficacy of aponermin in patients with relapsed or refractory multiple myeloma (RRMM). To confirm the superiority of aponermin plus thalidomide and dexamethasone (aponermin group) over placebo plus thalidomide and dexamethasone (placebo group) in RRMM, a randomized, double-blinded, placebo controlled phase 3 trial was performed. METHODS: Four hundred seventeen patients with RRMM who had previously received at least two regimens were randomly assigned (2:1) to receive aponermin, thalidomide, and dexamethasone or placebo, thalidomide, and dexamethasone. The primary endpoint was progression-free survival (PFS). Key secondary endpoints included overall survival (OS) and overall response rate (ORR). RESULTS: A total of 415 patients received at least one dose of trial treatment (276 vs. 139). The median PFS was 5.5 months in the aponermin group and 3.1 months in the placebo group (hazard ratio, 0.62; 95% confidence interval [CI], 0.49-0.78; P < 0.001). The median OS was 22.4 months for the aponermin group and 16.4 months for the placebo group (hazard ratio, 0.70; 95% CI, 0.55-0.89; P = 0.003). Significantly higher rates of ORR (30.4% vs. 13.7%, P < 0.001) and very good partial response or better (14.1% vs. 2.2%, P < 0.0001) were achieved in the aponermin group than in the placebo group. Treatment with aponermin caused hepatotoxicity in some patients, as indicated by the elevated alanine transaminase, aspartate transaminase, or lactate dehydrogenase levels (52.2% vs. 24.5%, 51.1% vs. 19.4% and 44.9% vs. 21.6%, respectively), mostly grade 1/2, transient and reversible. The main grade 3/4 adverse events included neutropenia, pneumonia and hyperglycemia. The incidence of serious adverse events was similar between the two groups (40.6% vs. 37.4%). There was no evidence that aponermin leads to hematological toxicity, nephrotoxicity, cardiotoxicity, or secondary tumors. CONCLUSIONS: Aponermin plus thalidomide and dexamethasone significantly improved PFS, OS and ORR with manageable side effects in RRMM patients who had received at least two prior therapies. These results support the use of aponermin, thalidomide, and dexamethasone as a treatment option for RRMM patients. TRIAL REGISTRATION: The trial was registered at http://www.chictr.org.cn as ChiCTR-IPR-15006024, 17/11/2014.


Asunto(s)
Mieloma Múltiple , Neutropenia , Humanos , Mieloma Múltiple/patología , Talidomida , Dexametasona , Recurrencia Local de Neoplasia/patología , Neutropenia/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
3.
Sensors (Basel) ; 23(22)2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38005590

RESUMEN

The accuracy of the line-of-sight of aviation photoelectric optoelectronic stabilization platforms is limited by two factors: external disturbance and sensor noise. An extended state observer (ESO) can effectively improve their anti-interference ability. However, due to the serious problem of gyroscope noise, further improvement of an ESO's disturbance suppression effect is limited. This article proposes a control structure that combines a Kalman filter (KF) and ESO, effectively improving upon the interference suppression ability of a traditional ESO under the influence of noise. Firstly, an ESO was used to observe the lumped disturbance of the system, and then, the observed disturbance was compensated for in the control loop. Secondly, based on the compensation servo control system, the state equation of the system was reconstructed using a Kalman filter. Finally, the reconstructed filtered state variables were iterated onto the universal state observer, achieving the observation of disturbances while filtering out sensor noise. Under the conditions of a laboratory flight simulation turntable, the line-of-sight stability accuracy level was improved under disturbance excitation. It can be seen that the combination of a Kalman filter and extended disturbance observer proposed in this project improves the ESO's anti-interference ability under the influence of noise.

4.
Sensors (Basel) ; 22(9)2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35591153

RESUMEN

At present, the cogging torque of permanent magnet synchronous motors (PMSM) seriously limits the Los pointing accuracy of aviation photoelectric stabilization platforms based on PMSM, which also restricts the requirements of ultra-long-distance and high-precision aviation reconnaissance and detection. For this problem, an off-line iterative learning control (ILC) was designed, and on this basis, a control method of negative effect compensation of disturbance (NECOD) is proposed. Firstly, the "dominant disturbance torque" in the system, that is, the cogging torque with the characteristics of position periodicity, was suppressed by off-line ILC according to different positions. Then, for the "residual disturbance" after compensation, NECOD was used to suppress it. In the constant speed scanning experiment of the aviation photoelectric stabilization platform, the method of combining the off-line iterative learning controller and the negative effect compensation of disturbance (NECOD + ILC) proposed in this paper significantly improved the Los control accuracy of the platform when compared with the classical active disturbance rejection control (ADRC) and ADRC + ILC methods, and the Los pointing error of the constant speed scanning process had only increased by less than 5% when the system had ±15% parameter perturbation. In addition, NECOD + ILC has fewer parameters and is easy to adjust, which is conducive to engineering application and promotion.


Asunto(s)
Algoritmos , Aviación , Imanes , Torque
5.
Int J Cancer ; 148(12): 3071-3085, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609405

RESUMEN

Multiple myeloma (MM), a hematological malignancy, has a poor prognosis and requires an invasive procedure. Reports have implicated miRNAs in the diagnosis, treatment and prognosis of hematological malignancies. In our study, we evaluated the expression profiles of miR-17-3p in plasma and bone marrow mononuclear cells of monoclonal gammopathy of undetermined significance (MGUS) and MM patients and healthy subjects. The results showed that the plasma and mononuclear cell expression levels of miR-17-3p in MM patients were higher than those in MGUS patients and normal controls. In addition, the expression of miR-17-3p was positively correlated with diagnostic indexes, such as marrow plasma cell abundance and serum M protein level, and positively correlated with the International Staging System stage of the disease. Receiver operating characteristic curve analysis suggested that miR-17-3p might be a diagnostic index of MM. Moreover, miR-17-3p regulated cell proliferation, apoptosis and the cell cycle through P21 in MM cell lines and promoted MM tumor growth in vivo. Furthermore, we predicted and verified LMLN as a functional downstream target gene of miR-17-3p. Negatively regulated by miR-17-3p, LMLN inhibits MM cell growth, exerting a tumor suppressive function through P21. Taken together, our data identify miR-17-3p as a promising diagnostic biomarker for MM in the clinic and unveil a new miR-17-3p-LMLN-P21 axis in MM progression.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Metaloendopeptidasas/genética , MicroARNs/genética , Mieloma Múltiple/patología , Regulación hacia Arriba , Adulto , Anciano , Anciano de 80 o más Años , Animales , Línea Celular Tumoral , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Metaloendopeptidasas/metabolismo , Ratones , Persona de Mediana Edad , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Trasplante de Neoplasias
6.
Opt Express ; 29(2): 1396-1411, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726356

RESUMEN

A measurement system based on a simple double-beam interferometry is built to realize the measurement of air refractive index with high accuracy. The basic principle of the system is that, through measuring the change of optical path difference caused by rapid and smooth vacuumization, measurement of refractive index of air is converted to length measurement. Error correction and signal processing are studied to ensure high-accuracy measurement of the refractive index of air. Three applicable methods are used in system. The system based on the methods realize the subdivision and counting of interference fringe by software with three-error correction, error compensation for the end-window plates' thickness change caused by vacuumization, steady realization of high vacuum conditions. To verify the accuracy and reliability of the system, the measurement results are compared with that obtained from the method based on empirical Edlén's formula. Analysis result shows that the expanded measurement uncertainty of the system is U = 5×10-9, with k = 2. The system can be used to compensate the laser wavelength error caused by the refractive index of air with high accuracy.

7.
PLoS Biol ; 16(12): e2006838, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30586380

RESUMEN

The disc-large (DLG)-membrane-associated guanylate kinase (MAGUK) family of proteins forms a central signaling hub of the glutamate receptor complex. Among this family, some proteins regulate developmental maturation of glutamatergic synapses, a process vulnerable to aberrations, which may lead to neurodevelopmental disorders. As is typical for paralogs, the DLG-MAGUK proteins postsynaptic density (PSD)-95 and PSD-93 share similar functional domains and were previously thought to regulate glutamatergic synapses similarly. Here, we show that they play opposing roles in glutamatergic synapse maturation. Specifically, PSD-95 promoted, whereas PSD-93 inhibited maturation of immature α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid-type glutamate receptor (AMPAR)-silent synapses in mouse cortex during development. Furthermore, through experience-dependent regulation of its protein levels, PSD-93 directly inhibited PSD-95's promoting effect on silent synapse maturation in the visual cortex. The concerted function of these two paralogs governed the critical period of juvenile ocular dominance plasticity (jODP), and fine-tuned visual perception during development. In contrast to the silent synapse-based mechanism of adjusting visual perception, visual acuity improved by different mechanisms. Thus, by controlling the pace of silent synapse maturation, the opposing but properly balanced actions of PSD-93 and PSD-95 are essential for fine-tuning cortical networks for receptive field integration during developmental critical periods, and imply aberrations in either direction of this process as potential causes for neurodevelopmental disorders.


Asunto(s)
Homólogo 4 de la Proteína Discs Large/fisiología , Guanilato-Quinasas/fisiología , Proteínas de la Membrana/fisiología , Sinapsis/metabolismo , Animales , Homólogo 4 de la Proteína Discs Large/metabolismo , Fármacos actuantes sobre Aminoácidos Excitadores , Femenino , Ácido Glutámico/metabolismo , Guanilato-Quinasas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/fisiología , Receptores AMPA/metabolismo , Receptores de Glutamato/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Transducción de Señal , Transmisión Sináptica/fisiología , Corteza Visual/metabolismo
8.
Cereb Cortex ; 29(10): 4067-4076, 2019 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-30462151

RESUMEN

Clarifying learning-induced synaptic plasticity in hippocampal circuits is critical for understanding hippocampal mechanisms of memory acquisition and storage. Many in vitro studies have demonstrated learning-associated plasticity at hippocampal synapses. However, as a neural basis of memory encoding, the nature of synaptic plasticity underlying hippocampal neuronal responses to memorized stimulation remains elusive. Using in vivo whole-cell recording in anaesthetized adult rats and mice, we investigated synaptic activity of hippocampal CA1 pyramidal cells (PCs) in response to a flash of visual stimulation as the conditioned stimulus (CS) in associative fear conditioning. We found that shortly (<3 days) after conditioning, excitatory synaptic responses and spiking responses to the flash CS emerged in a large number (~70%) of CA1 PCs, a neuronal population previously unresponsive to the flash before conditioning. The learning-induced CA1 excitatory responsiveness was further indicated to result from postsynaptic unsilencing at flash-associated silent synapses, with NMDA receptor-gated responses we recently reported in naive animals. Our findings suggest that associative fear learning can induce excitatory responsiveness to the memorized CS in a large population of CA1 neurons, via a process of postsynaptic unsilencing at CA1 silent synapses, which may be critical for hippocampal acquisition and storage of associative memory.


Asunto(s)
Región CA1 Hipocampal/fisiología , Condicionamiento Clásico/fisiología , Miedo , Memoria/fisiología , Plasticidad Neuronal , Células Piramidales/fisiología , Sinapsis/fisiología , Acrilatos , Animales , Femenino , Potenciales de la Membrana , Ratones , Éteres Fenílicos , Estimulación Luminosa , Ratas Sprague-Dawley
9.
Acta Haematol ; 142(4): 208-216, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31163428

RESUMEN

BACKGROUND: miR-886-5p plays an important role in many tumors, but it has been rarely investigated in multiple myeloma (MM). We studied the expression of miR-886-5p in the plasma of MM patients and in MM cell lines, and evaluated its biological function to identify its potential involvement in MM. METHODS: We recruited 16 subjects including 10 newly diagnosed MM patients who had not received treatment and 6 healthy individuals. The expression of miR-886-5p in plasma and MM cell lines was examined by quantitative reverse transcription polymerase chain reaction. Cell Counting Kit-8, colony formation assay, and 7-amino-actinomycin D/allophycocyanin double staining were performed to detect the function of miR-886-5p in MM cell lines. The expression of Bax and p53 was determined by western blot. RESULTS: The expression of miR-886-5p in the plasma of MM patients was higher than that in normal individuals and its level in MM cell lines was higher than that in peripheral blood mononuclear cells isolated from healthy individuals. miR-886-5p could trigger the cell proliferation and inhibition of apoptosis and affect the cell cycle. CONCLUSION: miR-886-5p triggered MM cell growth and may act as a diagnostic plasma biomarker for MM, potentially contributing to resistance to chemotherapy.


Asunto(s)
Biomarcadores de Tumor/sangre , Leucocitos Mononucleares/metabolismo , MicroARNs/sangre , Mieloma Múltiple/sangre , ARN Neoplásico/sangre , Adulto , Anciano , Apoptosis , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Leucocitos Mononucleares/patología , Masculino , Persona de Mediana Edad , Proteína p53 Supresora de Tumor/biosíntesis , Proteína X Asociada a bcl-2/biosíntesis
10.
Artif Organs ; 43(10): 1028-1034, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30972806

RESUMEN

This study aims to review the clinical efficacy and factors affecting the treatment of multiple myeloma (MM) by autologous hematopoietic stem cell transplantation (ASCT). The clinical data of 47 patients with MM from the Department of Hematology of Henan Cancer Hospital from September 2010 to July 2018 were retrospectively analyzed. At pre-transplantation of autologous cells, 25.5% were in complete remission (CR), 14.9% were in very good partial remission (VGPR) and 59.6% were in partial remission (PR). Among these cases, one case had PR after three recurrences. At post-transplantation, 51% were in CR, including two cases who received double transplantations, 27.7% were in VGPR, and 21.3% were in PR. The median follow-up time was 27.6 months (4-96 months). The 3-year progression free survival (PFS) and overall survival (OS) were 47.9% and 79.6%, respectively. The Analysis of variance (ANOVA) results revealed that factors that affected OS were international staging system (ISS) stage (P = 0.002), CR and VGPR post-transplantation (P = 0.002), while factors that affected PFS were ISS stage (P = 0.005), pre-transplant induction therapy (P = 0.032), and disease risk stratification (P = 0.017). The curative effects for PFS were CR and VGPR pre-transplantation (P = 0.013) and post-transplantation (P = 0.011). The Cox multivariate regression analysis revealed that ISS stage and CR and VGPR post-transplantation were independent prognostic factors of OS. At post-transplantation, CR and VGPR, ISS stage, and pre-transplant induction therapy were independent prognostic factors for PFS. In conclusion, ASCT can improve the clinical efficacy and survival rate of MM patients. ISS stage, CR and VGPR post-transplantation are independent prognostic factors of OS and PFS, while pre-transplant induction therapy is an independent prognostic factor for PFS.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Mieloma Múltiple/terapia , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/diagnóstico , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Trasplante Autólogo , Resultado del Tratamiento
11.
J Physiol ; 596(10): 1965-1979, 2018 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-29512156

RESUMEN

KEY POINTS: Sensory information processing in hippocampal circuits is critical for numerous hippocampus-dependent functions, but the underlying synaptic mechanism remains elusive. We performed whole-cell recording in vivo to examine visually evoked synaptic activity in hippocampal CA1 pyramidal cells (PCs). We first found that at resting potentials, ∼30% of CA1 PCs showed synaptic responses to a flash of visual stimulation. Interestingly, at depolarizing potentials, nearly all CA1 PCs were found to exhibit NMDA receptor-dependent responses, indicating the presence of NMDA receptor-mediated gating of CA1 responses. The NMDA receptor-gated CA1 responses may play important roles in the hippocampal function that depends on sensory information processing. ABSTRACT: Hippocampal processing of environmental information is critical for hippocampus-dependent brain functions that result from experience-induced hippocampal plasticity, such as memory acquisition and storage. Hippocampal responses to sensory stimulation have been extensively investigated, particularly with respect to spike activity. However, the synaptic mechanism for hippocampal processing of sensory stimulation has been much less understood. Here, we performed in vivo whole-cell recording on hippocampal CA1 pyramidal cells (PCs) from adult rodents to examine CA1 responses to a flash of visual stimulation. We first found in recordings obtained at resting potentials that ∼30% of CA1 PCs exhibited significant excitatory/inhibitory membrane-potential (MP) or membrane-current (MC) responses to the flash stimulus. Remarkably, in the other (∼70%) CA1 PCs, although no responses could be detected at resting potentials, clear excitatory MP or MC responses to the same flash stimulus were observed at depolarizing potentials, and these responses were further found to depend on NMDA receptors. Our findings demonstrate the presence of NMDA receptor-mediated gating of visual responses in hippocampal CA1 neurons, a synaptic mechanism for hippocampal processing of sensory information that may play important roles in hippocampus-dependent functions such as learning and memory.


Asunto(s)
Región CA1 Hipocampal/fisiología , Potenciales Postsinápticos Excitadores , Neuronas/fisiología , Células Piramidales/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Percepción Visual/fisiología , Animales , Región CA1 Hipocampal/citología , Potenciales Evocados , Femenino , Masculino , Potenciales de la Membrana , Ratones , Ratones Endogámicos C57BL , Neuronas/citología , Células Piramidales/citología , Ratas , Ratas Sprague-Dawley , Transmisión Sináptica
12.
Acta Haematol ; 139(2): 96-100, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29402764

RESUMEN

BACKGROUND: Multiple myeloma (MM) with 1q21 gains invariably has a poor prognosis. Many recent studies have reported the relationship between micro (mi)RNA expression and MM prognosis. However, there is little information on the association between miRNA alterations and 1q21 gains. METHODS: We compared the miRNA expression profiles of MM with 1q21 gains and MM with normal fluorescence in situ hybridisation (FISH) by gene expression array. Differentially expressed miRNAs were identified using Affymetrix TAC software. Thresholds were defined as a false discovery rate <0.05, p value <0.05, and n-fold change >2. RESULTS: Six miRNAs (let-7f-5p and -7g-5p, and miR-29a-3p, -29b-1-5p, -331-3p, and -223-3p) were downregulated and 4 (miR-30e-5p, -17-3p, -18b-5p, and -19a-3p) were upregulated in MM with 1q21 gains relative to MM with normal FISH. CONCLUSIONS: The identified set of miRNAs can serve as biomarkers for distinguishing MM with 1q21 gains from MM with normal FISH.


Asunto(s)
Duplicación Cromosómica , Cromosomas Humanos Par 1 , MicroARNs/genética , Mieloma Múltiple/genética , Transcriptoma , Adulto , Anciano , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Persona de Mediana Edad , Mieloma Múltiple/diagnóstico , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos
13.
Clin Exp Pharmacol Physiol ; 45(12): 1325-1327, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30075047

RESUMEN

Recombinant human endostatin (rhES) can inhibit multiple myeloma, while its clinical efficacy in treating relapsed refractory multiple myeloma (RRMM) has not been assessed. One hundred and eleven RRMM patients were treated with four different regimens: combination of VD (velcade+dexamethasone) and rhES (n = 25), Thalidomide (Tha) and VD (VTD, n = 22) combination, rhES and conventional chemotherapy combination (n = 32), and combination of conventional chemotherapy and Tha (n = 32). Significant differences were found in progression-free survival (PFS) between rhES combination groups and conventional chemotherapy combination groups. No statistical difference was found in overall response rate, overall survival or incidences of adverse effects. The combination of rhES with VD or conventional chemotherapy is active in patients with RRMM and prolongs the PFS to improve the quality of life.


Asunto(s)
Endostatinas/farmacología , Mieloma Múltiple/tratamiento farmacológico , Proteínas Recombinantes/farmacología , Supervivencia sin Enfermedad , Endostatinas/uso terapéutico , Humanos , Proteínas Recombinantes/uso terapéutico , Recurrencia , Insuficiencia del Tratamiento
14.
J Physiol ; 595(15): 5327-5340, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28555875

RESUMEN

KEY POINTS: Learning and memory storage requires neuronal plasticity induced in the hippocampus and other related brain areas, and this process is thought to rely on synchronized activity in neural networks. We used paired whole-cell recording in vivo to examine the synchronized activity that was induced in hippocampal CA1 neurons by associative fear learning. We found that both membrane potential synchronization and spike synchronization of CA1 neurons could be transiently enhanced after task learning, as observed on day 1 but not day 5. On day 1 after learning, CA1 neurons showed a decrease in firing threshold and rise times of suprathreshold membrane potential changes as well as an increase in spontaneous firing rates, possibly contributing to the enhancement of spike synchronization. The transient enhancement of CA1 neuronal synchronization may play important roles in the induction of neuronal plasticity for initial storage and consolidation of associative memory. ABSTRACT: The hippocampus is critical for memory acquisition and consolidation. This function requires activity- and experience-induced neuronal plasticity. It is known that neuronal plasticity is largely dependent on synchronized activity. As has been well characterized, repetitive correlated activity of presynaptic and postsynaptic neurons can lead to long-term modifications at their synapses. Studies on network activity have also suggested that memory processing in the hippocampus may involve learning-induced changes of neuronal synchronization, as observed in vivo between hippocampal CA3 and CA1 networks as well as between the rhinal cortex and the hippocampus. However, further investigation of learning-induced synchronized activity in the hippocampus is needed for a full understanding of hippocampal memory processing. In this study, by performing paired whole-cell recording in vivo on CA1 pyramidal cells (PCs) in anaesthetized adult rats, we examined CA1 neuronal synchronization before and after associative fear learning. We first found in naive animals that there was a low level of membrane potential (MP) synchronization and spike synchronization of CA1 PCs. In conditioned animals, we found a significant enhancement of both MP synchronization and spike synchronization, as observed on day 1 after learning, and this enhancement was transient and not observed on day 5. Accompanying learning-induced synchronized activity was a decreased firing threshold and rise time of suprathreshold MP changes as well as an increased spontaneous firing rate, possibly contributing to the enhanced spike synchronization. The transiently enhanced CA1 neuronal synchronization may have important roles in generating neuronal plasticity for hippocampal storage and consolidation of associative memory traces.


Asunto(s)
Región CA1 Hipocampal/fisiología , Miedo/fisiología , Memoria/fisiología , Células Piramidales/fisiología , Animales , Masculino , Ratas Sprague-Dawley
15.
Toxicol Appl Pharmacol ; 318: 69-78, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28115189

RESUMEN

Recently, oxidative stress is involved in hepatofibrogenesis. Matrix metalloproteinase-2 (MMP-2) is required for activation of hepatic stellate cells (HSCs) in response to reactive oxygen species (ROS). This study was designed to explore the hypothesis that the inhibitory effect of rosmarinic acid (RA) on HSCs activation might mainly result from its antioxidant capability by increasing the synthesis of glutathione (GSH) involved in nuclear factor kappa B (NF-κB)-dependent inhibition of MMP-2 activity. Here, we demonstrate that RA reverses activated HSCs to quiescent cells. Concomitantly, RA inhibits MMP-2 activity. RNA interference-imposed knockdown of NF-κB abolished down-regulation of MMP-2 by RA. RA-mediated inactivation of NF-κB could be blocked by the diphenyleneiodonium chloride (DPI; a ROS inhibitor). Conversely, transfection of dominant-negative (DN) mutant of extracellular signal-regulated kinases 2 (ERK2), c-Jun N-terminal kinase 1 (JNK1), or p38α kinase had no such effect. Simultaneously, RA suppresses ROS generation and lipid peroxidation (LPO) whereas increases cellular GSH in HSC-T6 cells. Furthermore, RA significantly increased antioxidant response element (ARE)-mediated luciferase activity, nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and catalytic subunits from glutamate cysteine ligase (GCLc) expression, but not modulatory subunits from GCL (GCLm). RA-mediated up-regulation of GClc is inhibited by the shRNA-induced Nrf2 knockdown. The knocking down of Nrf2 or buthionine sulfoximine (a GCL inhibitor) abolished RA-mediated inhibition of ROS. Collectively, these results provide novel insights into the mechanisms of RA as an antifibrogenic candidate in the prevention and treatment of liver fibrosis.


Asunto(s)
Antioxidantes/farmacología , Cinamatos/farmacología , Depsidos/farmacología , Células Estrelladas Hepáticas/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Línea Celular Transformada , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Activación Enzimática/fisiología , Células Estrelladas Hepáticas/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Ácido Rosmarínico
16.
Healthc Technol Lett ; 11(2-3): 157-166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638498

RESUMEN

This study focuses on enhancing the inference speed of laparoscopic tool detection on embedded devices. Laparoscopy, a minimally invasive surgery technique, markedly reduces patient recovery times and postoperative complications. Real-time laparoscopic tool detection helps assisting laparoscopy by providing information for surgical navigation, and its implementation on embedded devices is gaining interest due to the portability, network independence and scalability of the devices. However, embedded devices often face computation resource limitations, potentially hindering inference speed. To mitigate this concern, the work introduces a two-fold modification to the YOLOv7 model: the feature channels and integrate RepBlock is halved, yielding the YOLOv7-RepFPN model. This configuration leads to a significant reduction in computational complexity. Additionally, the focal EIoU (efficient intersection of union) loss function is employed for bounding box regression. Experimental results on an embedded device demonstrate that for frame-by-frame laparoscopic tool detection, the proposed YOLOv7-RepFPN achieved an mAP of 88.2% (with IoU set to 0.5) on a custom dataset based on EndoVis17, and an inference speed of 62.9 FPS. Contrasting with the original YOLOv7, which garnered an 89.3% mAP and 41.8 FPS under identical conditions, the methodology enhances the speed by 21.1 FPS while maintaining detection accuracy. This emphasizes the effectiveness of the work.

17.
Pharm Biol ; 2013 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-24192313

RESUMEN

Abstract Context: Hepatic fibrosis ultimately leads to cirrhosis if not treated effectively. Hepatic stellate cells (HSC) are a main mediator of hepatic fibrosis through the accumulation of extracellular matrix proteins. Suppression activation of passaged HSC has been proposed as therapeutic strategies for the treatment and prevention of hepatic fibrosis. Objective: To evaluate the effect of hydroxysafflor yellow A (HSYA), an active chemical compound derived from the flowers of Carthamus tinctorius L. (Compositae), on HSC inhibition, and to begin elucidating underlying mechanisms. Materials and methods: Primary HSCs were isolated from rats by in situ pronase/collagenase perfusion. Culture-activated HSCs were treated with or without HSYA at 30 µM in the presence or absence of PD98059 for 48 h, and then cell proliferation was measured by MTS assays. Messenger RNA (mRNA) expression was quantified by polymerase chain reaction, and protein was quantified by Western blots or enzyme-linked immunosorbent assays. Results: HSYA significantly inhibits culture-activated HSC proliferation in a dose-dependent and time-dependent manner with an IC50 value of 112.79 µM. HSYA (30 µM) induce the suppression of HSC activation, as indicated by decreases in contents of type I alpha collagen in HSC-cultured media and expression of α-smooth muscle actin protein in culture-activated HSC by 55 and 71%, respectively. HSYA (30 µM) also caused significant decreases in mRNA expression of type III alpha collagen in HSC by 28%. HSYA (30 µM) suppresses myocyte enhancer factor 2 C (MEF2C) expression both at its mRNA and protein levels by 60 and 61%, respectively. Further study demonstrated that HSYA (30 µM) caused significant decreases in p-ERK5 by 49%. Blocking extracellular signal-regulated protein kinase 5 (ERK5) activity by XMD 8--92, an ERK5 inhibitor, markedly abrogated the inhibitive effects of HSYA on HSC activation, and blocked the HSYA-mediated MEF2C down-regulation. Conclusions: HSYA suppress HSC activation by ERK5-mediated MEF2C down-regulation and makes it a potential candidate for prevention and treatment of hepatic fibrogenesis.

18.
Am J Cancer Res ; 13(4): 1611-1616, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37168351

RESUMEN

An open-label, single-center, phase 2 trial of a second-line therapy comprising low-dose decitabine (DAC) plus bortezomib (Bort) and dexamethasone (DXM) (Dvd) in relapsed and/or refractory multiple myeloma (RRMM) patients was conducted to screen available and inexpensive agents, aiming to work synergistically with other existing anti-melanoma drugs at reasonable prices, and effectively treat Bort and/or Len-refractory patients. Forty-seven patients were included according to the inclusion criteria, with only 1 withdrawal due to premature death. After 17.2 (range: 0.5-24.1) months of median follow-up, all the 46 cases had halted or completed DVd therapy per protocol, with an overall response rate (ORR) of 87.0%. Meanwhile, DVd was indicated to induce high, deep, and lasting responses, dependent of prior treatment or baseline characteristics. The results revealed that DVd is well-tolerated and highly effective in the treatment of first-relapsed RRMM (including those with Bort-refractory disease) patients.

19.
Zhongguo Gu Shang ; 36(1): 43-7, 2023 Jan 25.
Artículo en Zh | MEDLINE | ID: mdl-36653005

RESUMEN

OBJECTIVE: To investigate the clinical efficacy and safety of percutaneous foraminal endoscopy in the treatment of lumbar lateral recess stenosis in elderly. METHODS: The clinical data of 31 elderly patients with lumbar lateral recess stenosis treated by percutaneous foraminal endoscopic decompression from March 2018 to August 2019 were retrospectively analyzed. Including 16 males and 15 females, aged from 65 to 81 years with an average of (71.13±5.20) years, the course of disease ranged from 3 months to 7 years with an average of (14.36±6.52) months. Visual analogue scale (VAS) and Oswestry disability index (ODI) were used to assess clinical symptom and functional status before operation and 1, 6, 12 months after operation. At the final follow-up, the modified Macnab standard was used to evaluate clinical efficacy. RESULTS: All patients were completed the operation successfully. The operation time was from 75 to 120 min with an average of (97.84±11.22 ) min. All 31 patients were followed up from 12 to 28 months with an average of (17.29±5.56) months. Postoperative lumbago-leg pain VAS and ODI were significantly improved at 1, 6, and 12 months(P<0.01). At the final follow-up, according to the modified Macnab standard to evaluate the effect, 23 got excellent results, 5 good, 3 fair. One patient had severe adhesions between peripheral tissues and nerve root, and postoperative sensory abnormalities in the lower extremities were treated conservatively with traditional Chinese medicine and neurotrophic drugs, which recovered at 2 weeks after surgery. No complications such as nerve root injury and infection occurred. CONCLUSION: The intervertebral foraminal endoscopy technique, which is performed under local anesthesia for a short period of operation, ensures adequate decompression while minimizing complications, and is a safe and effective surgical procedure for elderly patients with lumbar lateral recess stenosis.


Asunto(s)
Estenosis Espinal , Masculino , Femenino , Humanos , Anciano , Lactante , Constricción Patológica/cirugía , Estenosis Espinal/cirugía , Descompresión Quirúrgica/métodos , Estudios Retrospectivos , Vértebras Lumbares/cirugía , Endoscopía/métodos , Resultado del Tratamiento
20.
J Inflamm Res ; 16: 2585-2594, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37350774

RESUMEN

Objective: To examine the clinical characteristics and anemia-related factors in patients with newly diagnosed multiple myeloma (NDMM), as well as the effect and mechanism of erythroblastic islands (EBIs) and EBI macrophages in NDMM patients with anemia. Methods: We collected and analyzed clinical data to find anemia-related factors. Using flow cytometry, the numbers and ratios of erythroblasts and EBI macrophages were determined. RNA sequencing (RNA-seq) was used to determine the differences of EBI macrophages in NDMM patients with or without anemia. Results: Based on the clinical characteristics of NDMM patients with anemia, MCV, abnormal levels of albumin, osteolytic lesions, and Durie-Salmon (DS) stage are risk factors for anemia. Patients with anemia have fewer erythroblasts, erythroblastic islands (EBIs), and EBI macrophages in their bone marrow than patients without anemia. RNA-seq analysis of EBI macrophages from the bone marrow of patients with and without anemia revealed that macrophages from patients with anemia are impaired and tend to promote the production of interleukin-6, which has been demonstrated to be an essential survival factor of myeloma cells and protects them from apoptosis. Conclusion: In NDMM patients with anemia, EBI macrophages are impaired, which causes anemia in those patients. Our finding highlights the significance of EBI macrophages in anemia in NDMM patients and provides a new strategy for recovery from anemia in these patients.

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