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1.
Nat Immunol ; 24(5): 827-840, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36928411

RESUMEN

Resident tissue macrophages (RTMs) are differentiated immune cells that populate distinct niches and exert important tissue-supportive functions. RTM maintenance is thought to rely either on differentiation from monocytes or on RTM self-renewal. Here, we used a mouse model of inducible lung interstitial macrophage (IM) niche depletion and refilling to investigate the development of IMs in vivo. Using time-course single-cell RNA-sequencing analyses, bone marrow chimeras and gene targeting, we found that engrafted Ly6C+ classical monocytes proliferated locally in a Csf1 receptor-dependent manner before differentiating into IMs. The transition from monocyte proliferation toward IM subset specification was controlled by the transcription factor MafB, while c-Maf specifically regulated the identity of the CD206+ IM subset. Our data provide evidence that, in the mononuclear phagocyte system, the ability to proliferate is not merely restricted to myeloid progenitor cells and mature RTMs but is also a tightly regulated capability of monocytes developing into RTMs in vivo.


Asunto(s)
Macrófagos , Monocitos , Animales , Ratones , Diferenciación Celular , Pulmón , Proliferación Celular , Factor de Transcripción MafB/genética
2.
Nat Immunol ; 16(9): 991-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26214740

RESUMEN

Induction of the transcriptional repressor Bcl-6 in CD4(+) T cells is critical for the differentiation of follicular helper T cells (T(FH) cells), which are essential for B cell-mediated immunity. In contrast, the transcription factor Blimp1 (encoded by Prdm1) inhibits T(FH) differentiation by antagonizing Bcl-6. Here we found that the transcription factor TCF-1 was essential for both the initiation of T(FH) differentiation and the effector function of differentiated T(FH) cells during acute viral infection. Mechanistically, TCF-1 bound directly to the Bcl6 promoter and Prdm1 5' regulatory regions, which promoted Bcl-6 expression but repressed Blimp1 expression. TCF-1-null T(FH) cells upregulated genes associated with non-T(FH) cell lineages. Thus, TCF-1 functions as an important hub upstream of the Bcl-6-Blimp1 axis to initiate and secure the differentiation of T(FH) cells during acute viral infection.


Asunto(s)
Diferenciación Celular/inmunología , Proteínas de Unión al ADN/inmunología , Factor Nuclear 1-alfa del Hepatocito/inmunología , Infecciones por Orthomyxoviridae/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Factores de Transcripción/inmunología , Animales , Diferenciación Celular/genética , Proteínas de Unión al ADN/genética , Centro Germinal/inmunología , Centro Germinal/metabolismo , Factor Nuclear 1-alfa del Hepatocito/genética , Virus de la Influenza A , Ratones , Ratones Noqueados , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Proteínas Proto-Oncogénicas c-bcl-6 , Linfocitos T Colaboradores-Inductores/metabolismo , Factores de Transcripción/genética
3.
Immunity ; 47(3): 538-551.e5, 2017 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-28930662

RESUMEN

Follicular regulatory T (Tfr) cells differentiate from conventional regulatory T (Treg) cells and suppress excessive germinal center (GC) responses by acting on both GC B cells and T follicular helper (Tfh) cells. Here, we examined the impact of mTOR, a serine/threonine protein kinase that senses and integrates diverse environmental cues, on the differentiation and functional competency of Tfr cells in response to protein immunization or viral infection. By genetically deleting Rptor or Rictor, essential components for mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2), respectively, we found that mTORC1 but not mTORC2 is essential for Tfr differentiation. Mechanistically, mTORC1-mediated phosphorylation of the transcription factor STAT3 induced the expression of the transcription factor TCF-1 by promoting STAT3 binding to the Tcf7 5'-regulatory region. Subsequently, TCF-1 bound to the Bcl6 promoter to induce Bcl6 expression, which launched the Tfr cell differentiation program. Thus, mTORC1 initiates Tfr cell differentiation by activating the TCF-1-Bcl-6 axis during immunization or infection.


Asunto(s)
Inmunomodulación , Complejos Multiproteicos/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Biomarcadores , Diferenciación Celular/inmunología , Análisis por Conglomerados , Perfilación de la Expresión Génica , Factor Nuclear 1-alfa del Hepatocito/metabolismo , Inmunización , Inmunofenotipificación , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Ratones Transgénicos , Complejos Multiproteicos/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Linfocitos T Reguladores/citología , Serina-Treonina Quinasas TOR/genética
4.
Small ; 20(21): e2308403, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38098457

RESUMEN

Keratitis, an inflammation of the cornea caused by bacterial or fungal infections, is one of the leading causes of severe visual disability and blindness. Keratitis treatment requires both the prevention of infection and the reduction of inflammation. However, owing to their limited therapeutic functions, in addition to the ocular barrier, existing conventional medications are characterized by poor efficacy and low bioavailability, requiring high dosages or frequent topical treatment, which represents a burden on patients and increases the risk of side effects. In this study, manganese oxide nanocluster-decorated graphdiyne nanosheets (MnOx/GDY) are developed as multienzyme-like nanozymes for the treatment of infectious keratitis and loaded into hyaluronic acid and polymethyl methacrylate-based ocular microneedles (MGMN). MGMN not only exhibits antimicrobial and anti-inflammatory effects owing to its multienzyme-like activities, including oxidase, peroxidase, catalase, and superoxide dismutase mimics but also crosses the ocular barrier and shows increased bioavailability via the microneedle system. Moreover, MGMN is demonstrated to eliminate pathogens, prevent biofilm formation, reduce inflammation, alleviate ocular hypoxia, and promote the repair of corneal epithelial damage in in vitro, ex vivo, and in vivo experiments, thus providing a better therapeutic effect than commercial ophthalmic voriconazole, with no obvious microbial resistance or cytotoxicity.


Asunto(s)
Queratitis , Agujas , Queratitis/tratamiento farmacológico , Animales , Ratones , Enzimas/metabolismo , Biopelículas/efectos de los fármacos , Humanos , Óxidos , Compuestos de Manganeso
5.
Hepatobiliary Pancreat Dis Int ; 23(1): 77-82, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37087368

RESUMEN

BACKGROUND: Early systemic anticoagulation (SAC) is a common practice in acute necrotizing pancreatitis (ANP), and its impact on in-hospital clinical outcomes had been assessed. However, whether it affects long-term outcomes is unknown. This study aimed to evaluate the effect of SAC on 90-day readmission and other long-term outcomes in ANP patients. METHODS: During January 2013 and December 2018, ANP patients admitted within 7 days from the onset of abdominal pain were screened. The primary outcome was 90-day readmission after discharge. Cox proportional-hazards regression model and mediation analysis were used to define the relationship between early SAC and 90-day readmission. RESULTS: A total of 241 ANP patients were enrolled, of whom 143 received early SAC during their hospitalization and 98 did not. Patients who received early SAC experienced a lower incidence of splanchnic venous thrombosis (SVT) [risk ratio (RR) = 0.40, 95% CI: 0.26-0.60, P < 0.01] and lower 90-day readmission with an RR of 0.61 (95% CI: 0.41-0.91, P = 0.02) than those who did not. For the quality of life, patients who received early SAC had a significantly higher score in the subscale of vitality (P = 0.03) while the other subscales were all comparable between the two groups. Multivariable Cox regression model showed that early SAC was an independent protective factor for 90-day readmission after adjusting for potential confounders with a hazard ratio of 0.57 (95% CI: 0.34-0.96, P = 0.04). Mediation analysis showed that SVT mediated 37.0% of the early SAC-90-day readmission causality. CONCLUSIONS: The application of early SAC may reduce the risk of 90-day readmission in the survivors of ANP patients, and reduced SVT incidence might be the primary contributor.


Asunto(s)
Pancreatitis Aguda Necrotizante , Trombosis de la Vena , Humanos , Readmisión del Paciente , Estudios Retrospectivos , Pancreatitis Aguda Necrotizante/diagnóstico , Pancreatitis Aguda Necrotizante/tratamiento farmacológico , Calidad de Vida , Factores de Riesgo , Trombosis de la Vena/tratamiento farmacológico , Anticoagulantes/efectos adversos
6.
BMC Gastroenterol ; 23(1): 423, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38036993

RESUMEN

BACKGROUND: The present study aims to explore the clinical application of enhanced recovery after surgery (ERAS) in pediatric patients with congenital upper gastrointestinal obstruction (CUGIO). METHODS: A total of 82 pediatric patients with CUGIO admitted to the neonatal intensive care unit in Kunming Children's Hospital between June 2017 and June 2021 were enrolled in the present study and divided into two groups: the ERAS group (n = 46) and the control group (n = 36). The ERAS management mode was adopted in the ERAS group, and the conventional perioperative management mode was adopted in the control group. RESULTS: In the ERAS group and the control group, the time to the first postoperative bowel movement was 49.2 ± 16.6 h and 58.4 ± 18.8 h, respectively, and the time to the first postoperative feeding was 79 ± 7.1 h and 125.2 ± 8.3 h, respectively. The differences in the above two indicators between the two groups were statistically significant (P < 0.05). In the ERAS group, the days of parenteral nutrition and the length of hospital stay were 14.5 ± 2.3 d and 18.8 ± 6.4 d, respectively. In the control group, 17.6 ± 2.2 d and 23.1 ± 8.1 d, respectively. The differences in these two indicators between the two groups were statistically significant (P < 0.05). CONCLUSION: The ERAS management model had a positive effect on early postoperative recovery in pediatric patients with CUGIO.


Asunto(s)
Obstrucción Duodenal , Recuperación Mejorada Después de la Cirugía , Recién Nacido , Humanos , Niño , Obstrucción Duodenal/etiología , Obstrucción Duodenal/cirugía , Intestinos , Periodo Posoperatorio , Tiempo de Internación , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
7.
J Immunol ; 206(5): 1077-1087, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33483347

RESUMEN

The activation of T cells is accompanied by intensive posttranscriptional remodeling of their proteome. We observed that protein expression of enzymes that modify wobble uridine in specific tRNAs, namely elongator subunit 3 (Elp3) and cytosolic thiouridylase (Ctu)2, increased in the course of T cell activation. To investigate the role of these tRNA epitranscriptomic modifiers in T cell biology, we generated mice deficient for Elp3 in T cells. We show that deletion of Elp3 has discrete effects on T cells. In vitro, Elp3-deficient naive CD4+ T cells polarize normally but are delayed in entering the first cell cycle following activation. In vivo, different models of immunization revealed that Elp3-deficient T cells display reduced expansion, resulting in functional impairment of T follicular helper (TFH) responses, but not of other CD4+ effector T cell responses. Transcriptomic analyses identified a progressive overactivation of the stress-responsive transcription factor Atf4 in Elp3-deficient T cells. Overexpression of Atf4 in wild-type T cells phenocopies the effect of Elp3 loss on T cell cycle entry and TFH cell responses. Reciprocally, partial silencing of Atf4 or deletion of its downstream effector transcription factor Chop rescues TFH responses of Elp3-deficient T cells. Together, our results reveal that specific epitranscriptomic tRNA modifications contribute to T cell cycle entry and promote optimal TFH responses.


Asunto(s)
Factor de Transcripción Activador 4/genética , Histona Acetiltransferasas/genética , ARN de Transferencia/genética , Células T Auxiliares Foliculares/inmunología , Uridina/genética , Factor de Transcripción Activador 4/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Ciclo Celular/genética , Ciclo Celular/inmunología , Femenino , Histona Acetiltransferasas/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Procesamiento Postranscripcional del ARN/genética , Procesamiento Postranscripcional del ARN/inmunología , ARN de Transferencia/inmunología , Transcriptoma/genética , Transcriptoma/inmunología , Uridina/inmunología
8.
Am J Respir Cell Mol Biol ; 67(2): 241-252, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35522264

RESUMEN

Alveolar macrophages (AMs) are functionally important innate cells involved in lung homeostasis and immunity and whose diversity in health and disease is a subject of intense investigations. Yet, it remains unclear to what extent conditions like smoking or chronic obstructive pulmonary disease (COPD) trigger changes in the AM compartment. Here, we aimed to explore heterogeneity of human AMs isolated from healthy nonsmokers, smokers without COPD, and smokers with COPD by analyzing BAL fluid cells by flow cytometry and bulk and single-cell RNA sequencing. We found that subpopulations of BAL fluid CD206+ macrophages could be distinguished based on their degree of autofluorescence in each subject analyzed. CD206+ autofluorescenthigh AMs were identified as classical, self-proliferative AM, whereas autofluorescentlow AMs were expressing both monocyte and classical AM-related genes, supportive of a monocytic origin. Of note, monocyte-derived autofluorescentlow AMs exhibited a functionally distinct immunoregulatory profile, including the ability to secrete the immunosuppressive cytokine IL-10. Interestingly, single-cell RNA-sequencing analyses showed that transcriptionally distinct clusters of classical and monocyte-derived AM were uniquely enriched in smokers with and without COPD as compared with healthy nonsmokers. Of note, such smoking-associated clusters exhibited gene signatures enriched in detoxification, oxidative stress, and proinflammatory responses. Our study independently confirms previous reports supporting that monocyte-derived macrophages coexist with classical AM in the airways of healthy subjects and patients with COPD and identifies smoking-associated changes in the AM compartment that may favor COPD initiation or progression.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Fumar , Humanos , Pulmón , Macrófagos , Macrófagos Alveolares
9.
Anal Chem ; 94(39): 13598-13606, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36124415

RESUMEN

Graphdiyne (GDY) has been considered as an appealing electrode material for electrochemical sensing because of its alkyne-rich structure and high degrees of π-conjugation, which shows great affinity to heavy metal ions and pollutant molecules via d-π and π-π interactions. However, the low surface area and poor conductivity of bulk GDY limit its electrochemical performance. Herein, a two-dimensional ultrathin GDY/graphene (GDY/G) nanostructure was synthesized and used as an electrode material for electrochemical sensing. Graphene plays the role of an epitaxy template for few-layered GDY growth and conductive layers. The formed few-layered GDY with a high surface area possesses abundant affinity sites toward heavy metal ions (Cd2+, Pb2+) and toxic molecules, for example, nitrobenzene and 4-nitrophenol, via d-π and π-π interactions, respectively. Moreover, hemin as a key part of the enzyme catalytic motif was immobilized on GDY/G via π-π interactions. The artificial enzyme mimic hemin/GDY/G-modified electrode exhibited promising ascorbic acid and uric acid detection performance with excellent sensitivity and selectivity, a good linear range, and reproducibility. More importantly, real sample detection and the feasibility of this electrochemical sensor as a wearable biosensor were demonstrated.


Asunto(s)
Contaminantes Ambientales , Grafito , Alquinos , Ácido Ascórbico , Cadmio , Grafito/química , Hemina/química , Iones , Plomo , Nitrobencenos , Reproducibilidad de los Resultados , Ácido Úrico
10.
Small ; 18(2): e2104160, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34741419

RESUMEN

Metal peroxide nanoparticles designed to elevate the oxidative stress are considered a promising nanotherapeutics in biomedical applications, including chemotherapy, photodynamic therapy, and bacterial disinfection. However, their lack of specificity towards the therapeutic target can cause toxic side effects to healthy tissues. Here, silver peroxide nanoparticles (Ag2 O2 NPs) capable of controlled reactive oxygen species (ROS) release are synthesized. The release of bactericidal Ag+ ions and ROS is strictly regulated by external stimuli of ultrasound (US) and near-infrared (NIR) light. In vitro and in vivo investigations show that the Ag2 O2 NPs present enhanced antibacterial and antibiofilm capabilities with a killing efficiency >99.9999% in 10 min, significantly accelerate multi-drug resistant Staphylococcus aureus infected skin wound closure with excellent cytocompatibility and hemocompatibility. This work not only provides the first paradigm for fabricating silver peroxide nanoparticle but also introduces a highly efficient noninvasive and safe therapeutic modality for combating bacterial infectious diseases.


Asunto(s)
Nanopartículas del Metal , Staphylococcus aureus Resistente a Meticilina , Nanopartículas , Infecciones Estafilocócicas , Antibacterianos/farmacología , Humanos , Peróxidos , Terapia Fototérmica , Plata , Infecciones Estafilocócicas/terapia
11.
Nature ; 537(7620): 412-428, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27501245

RESUMEN

During chronic viral infection, virus-specific CD8(+) T cells become exhausted, exhibit poor effector function and lose memory potential. However, exhausted CD8(+) T cells can still contain viral replication in chronic infections, although the mechanism of this containment is largely unknown. Here we show that a subset of exhausted CD8(+) T cells expressing the chemokine receptor CXCR5 has a critical role in the control of viral replication in mice that were chronically infected with lymphocytic choriomeningitis virus (LCMV). These CXCR5(+) CD8(+) T cells were able to migrate into B-cell follicles, expressed lower levels of inhibitory receptors and exhibited more potent cytotoxicity than the CXCR5(-) [corrected] subset. Furthermore, we identified the Id2-E2A signalling axis as an important regulator of the generation of this subset. In patients with HIV, we also identified a virus-specific CXCR5(+) CD8(+) T-cell subset, and its number was inversely correlated with viral load. The CXCR5(+) subset showed greater therapeutic potential than the CXCR5(-) [corrected] subset when adoptively transferred to chronically infected mice, and exhibited synergistic reduction of viral load when combined with anti-PD-L1 treatment. This study defines a unique subset of exhausted CD8(+) T cells that has a pivotal role in the control of viral replication during chronic viral infection.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Centro Germinal/citología , Coriomeningitis Linfocítica/inmunología , Coriomeningitis Linfocítica/virología , Virus de la Coriomeningitis Linfocítica/inmunología , Receptores CXCR5/metabolismo , Traslado Adoptivo , Animales , Linfocitos B/inmunología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/trasplante , Diferenciación Celular , Enfermedad Crónica , Femenino , Centro Germinal/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Humanos , Proteína 2 Inhibidora de la Diferenciación/metabolismo , Virus de la Coriomeningitis Linfocítica/crecimiento & desarrollo , Masculino , Ratones , Receptores CXCR5/deficiencia , Transducción de Señal , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/trasplante , Carga Viral/inmunología , Replicación Viral/inmunología
12.
Sensors (Basel) ; 22(10)2022 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-35632062

RESUMEN

Hall-effect sensors are used for the non-destructive testing of wire ropes owing to their low power consumption and high operation frequency. The high-speed operation of wire ropes causes vibration inclination at different frequencies, which makes it difficult to detect the ropes. Considering that the radial signal in the magnetic flux leakage (MFL) detection method can respond to damages to the maximum extent possible, this study proposes a radial magnetic concentrator suitable for the non-destructive testing of wire ropes based on theoretical analysis and transient magnetic field simulations. The concentrator improves the radial magnetic circuit, polymerizes the leakage of the magnetic field in the detection device, and the leakage of the magnetic field of the defect converges at the sensor position of the circumferential array to improve the signal-to-noise ratio of the Hall-effect sensor. In addition, the MFL field is homogenized through the structure of the magnetic concentrator when the wire rope is tilted, which weakens the influence of the vibration tilt of the wire rope on the test results. Finally, the experiments show that the amplitude of the wire-rope damage signal is effectively improved by using the proposed radial magnetic concentration technology, hence being convenient for defect analyses.

13.
Zhonghua Nan Ke Xue ; 28(9): 831-836, 2022 Sep.
Artículo en Zh | MEDLINE | ID: mdl-37839010

RESUMEN

OBJECTIVE: To re-evaluate the clinical efficacy of Longjintonglin Capsules (LJTL) in the treatment of chronic prostatitis with damp-heat stasis syndrome. METHODS: This multicenter real-world study included 1 352 cases of chronic prostatitis with damp-heat and stagnation syndrome treated with LJTL (3 capsules once, tid, 30 minutes after meals, for 2 four-week courses) in addition to routine treatment. Before and after treatment, we analyzed the NIH-CPSI scores, the scores of Chinese medicine symptom quantitative classification and changes in individual symptom scores, and observed adverse reactions to medication. RESULTS: The total effectiveness rate of LJTL was 93.64%. Compared with the baseline, the NIH-CPSI scores were significantly decreased after treatment (ï¼»24.27 ± 6.04ï¼½ vs ï¼»8.17 ± 4.21ï¼½, P < 0.05), and so were the scores on the pain symptoms (ï¼»9.63 ± 3.65ï¼½ vs ï¼»3.02 ± 2.23ï¼½, P < 0.05), voiding symptoms (ï¼»5.65 ± 2.15ï¼½ vs ï¼»1.62 ± 1.36) and quality of life (ï¼»8.96 ± 2.32ï¼½ vs ï¼»3.16 ± 1.89ï¼½, P < 0.05). The effectiveness rate of LJTL was 95.9% on the Chinese medicine symptom frequent urination, 90.4% on painful urination, and 91.4% scanty dark urine, with a total effectiveness rate of 82.4% - 95.9%, all with statistically significant difference in comparison with the baseline (P < 0.05). CONCLUSION: Longjintonglin Capsules combined with routine treatment can significantly improve the clinical symptoms of chronic prostatitis with damp-heat stasis syndrome, especially effective on the symptoms of frequent urination, painful urination and scanty dark urine. Besides, it recommendable for its antidepressant and antianxiety effects, and the effect of improving the quality of life of the chronic prostatitis patients with damp-heat stasis.


Asunto(s)
Medicamentos Herbarios Chinos , Prostatitis , Masculino , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , Prostatitis/diagnóstico , Prostatitis/tratamiento farmacológico , Calor , Calidad de Vida , Enfermedad Crónica , Resultado del Tratamiento , Cápsulas/uso terapéutico
14.
Entropy (Basel) ; 23(9)2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34573832

RESUMEN

Robot manipulator trajectory planning is one of the core robot technologies, and the design of controllers can improve the trajectory accuracy of manipulators. However, most of the controllers designed at this stage have not been able to effectively solve the nonlinearity and uncertainty problems of the high degree of freedom manipulators. In order to overcome these problems and improve the trajectory performance of the high degree of freedom manipulators, a manipulator trajectory planning method based on a radial basis function (RBF) neural network is proposed in this work. Firstly, a 6-DOF robot experimental platform was designed and built. Secondly, the overall manipulator trajectory planning framework was designed, which included manipulator kinematics and dynamics and a quintic polynomial interpolation algorithm. Then, an adaptive robust controller based on an RBF neural network was designed to deal with the nonlinearity and uncertainty problems, and Lyapunov theory was used to ensure the stability of the manipulator control system and the convergence of the tracking error. Finally, to test the method, a simulation and experiment were carried out. The simulation results showed that the proposed method improved the response and tracking performance to a certain extent, reduced the adjustment time and chattering, and ensured the smooth operation of the manipulator in the course of trajectory planning. The experimental results verified the effectiveness and feasibility of the method proposed in this paper.

15.
Entropy (Basel) ; 23(11)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34828235

RESUMEN

In order to improve the accuracy of manipulator operation, it is necessary to install a tactile sensor on the manipulator to obtain tactile information and accurately classify a target. However, with the increase in the uncertainty and complexity of tactile sensing data characteristics, and the continuous development of tactile sensors, typical machine-learning algorithms often cannot solve the problem of target classification of pure tactile data. Here, we propose a new model by combining a convolutional neural network and a residual network, named ResNet10-v1. We optimized the convolutional kernel, hyperparameters, and loss function of the model, and further improved the accuracy of target classification through the K-means clustering method. We verified the feasibility and effectiveness of the proposed method through a large number of experiments. We expect to further improve the generalization ability of this method and provide an important reference for the research in the field of tactile perception classification.

16.
Zhonghua Nan Ke Xue ; 27(10): 934-940, 2021 10 20.
Artículo en Zh | MEDLINE | ID: mdl-34914273

RESUMEN

Circulating tumor cells (CTC) are tumor cells that escape from the primary or metastatic tumor into the circulatory system, and closely related to cancer metastasis. Since the samples can be obtained through simple and minimally invasive blood sampling operations, CTCs have a great clinical potential. PCa is one of the most common malignant tumors in men. In recent years, many scholars have conducted studies as to whether CTC technology can be used for the diagnosis and treatment of PCa, as well as for more accurate prediction of the risk of progression. This article summarizes the advances in researches relating CTC technology and the diagnosis and treatment of PCa. CTC detection has been developed from simple counting to phenotypic classification, and even to its combination with the determination of the expressions of specific genes (such as AR, AR-V7, etc.) and single-cell sequencing. Some reports showed that CTC technology has a certain significance in the early diagnosis of PCa, but its main value is demonstrated in drug sensitivity and prognosis evaluation in the late stage of the malignancy. The standardized detection methods and reference values of CTCs in PCa will be important research orientations in the near future.


Asunto(s)
Neoplasias Primarias Secundarias , Células Neoplásicas Circulantes , Neoplasias de la Próstata , Recuento de Células , Humanos , Masculino , Pronóstico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(6): 943-947, 2021 Nov.
Artículo en Zh | MEDLINE | ID: mdl-34841759

RESUMEN

The cultivation of medical students'research ability promotes in them high-quality career development. In addition to classroom instruction of the theoretical knowledge concerning research, the systematic training and practice of scientific research skills outside the classroom is also vitally important. We established the Volunteer Team of Gastric Cancer Surgery with the features of standardization, progressiveness, and practicality in order to cultivate the thinking skills concerning research and the research ability of medical students. Our team is supported by the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University. Taking clinical and basic research skills training as the focus of our work, we have organized systematic workshops focused on theoretical knowledge and research skills practice programs of divers forms. Our work helps improve the research ability of medical students, suggesting that research-oriented clubs play an active role in the cultivation of practical research ability of medical students and should be widely promoted.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Neoplasias Gástricas , Estudiantes de Medicina , China , Hospitales , Humanos , Neoplasias Gástricas/cirugía , Universidades , Voluntarios
18.
Cancer ; 126(4): 840-849, 2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-31714592

RESUMEN

BACKGROUND: The thoracic radiotherapy (TRT) target volume for limited-stage small-cell lung cancer (SCLC) has been controversial for decades. In this report, the final results of a prospective randomized trial on the TRT target volume before and after induction chemotherapy are presented. METHODS: After 2 cycles of etoposide and cisplatin, patients arm were randomized to receive TRT to the postchemotherapy or prechemotherapy tumor volume in a study arm and a control arm. Involved-field radiotherapy was received in both arms. TRT consisted of 1.5 grays (Gy) twice daily in 30 fractions to up to a total dose of 45 Gy. Lymph node regions were contoured, and intentional and incidental radiation doses were recorded. RESULTS: The study was halted early because of slow accrual. Between 2002 and 2017, 159 and 150 patients were randomized to the study arm or the control arm, respectively; and 21.4% and 19.1% of patients, respectively, were staged using positron emission tomography/computed tomography (P = .31). With a median follow-up of 54.1 months (range, 19.9-165.0 months) in survivors, the 3-year local/regional progression-free probability was 58.2% and 65.5% in the study and control arms, respectively (P = .44), and the absolute difference was -7.3% (95% CI, -18.2%, 3.7%). In the study and control arms, the median overall survival was 21.9 months and 26.6 months, respectively, and the 5-year overall survival rate was 22.8% and 28.1%, respectively (P = .26). Grade 3 esophagitis was observed in 5.9% of patients in the study arm versus 15.5% of those in the control arm (P = .01). The isolated out-of-field failure rate was 2.6% in the study arm versus 4.1% in the control arm (P = .46), and all such failures were located in the supraclavicular fossa or contralateral hilum. The regions 7, 3P, 4L, 6, 4R, 5, and 2L received incidental radiation doses >30 Gy. CONCLUSIONS: TRT could be limited to the postchemotherapy tumor volume, and involved-field radiotherapy could be routinely applied for limited-stage SCLC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pulmonares/terapia , Dosificación Radioterapéutica , Carcinoma Pulmonar de Células Pequeñas/terapia , Adulto , Anciano , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Cisplatino/administración & dosificación , Etopósido/administración & dosificación , Femenino , Humanos , Leucopenia/etiología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neumonía/etiología , Estudios Prospectivos , Fibrosis Pulmonar/etiología , Informe de Investigación , Carcinoma Pulmonar de Células Pequeñas/patología
19.
Small ; 16(34): e2001440, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32715643

RESUMEN

From manufacture to disposal, the interaction of graphdiyne based nanomaterials with living organisms is inevitable and crucial. However, the cytotoxic properties of this novel carbon nanomaterial are rarely investigated, and the mechanisms behind their cytotoxicity are totally unknown. In this study, the antibacterial activity of graphdiyne (GDY) and graphdiyne oxide (GDYO) is reported. GDY is capable of inhibiting broad-spectrum bacterial growth while exerting moderate cytotoxicity on mammalian cells. In comparison, GDYO exhibits lower antibacterial activity than that of GDY. Then an alterable, synergetic antibacterial mechanism of GDY, involving wrapping bacterial membrane, membrane insertion and disruption, and reactive oxygen species generation is demonstrated, while the differential gene expression analysis indicates that GDY could only alter the bacterial metabolism slightly and the oxidative stress route may be a minor bactericidal factor. The investigation of the antibacterial behaviors of GDY based nanomaterials may provide useful guidelines for the future design and application of this novel molecular allotrope of carbon.


Asunto(s)
Grafito , Nanoestructuras , Animales , Antibacterianos/farmacología , Óxidos/farmacología
20.
Insect Mol Biol ; 29(4): 381-390, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32291884

RESUMEN

Common ragweed (Ambrosia artemisiifolia) is a notorious invasive weed that has spread across most temperate regions of the world. The beetle (Ophraella communa) is considered to be an effective control agent against A. artemisiifolia. As an oligophagous insect, its olfactory system is extremely important for host seeking in the wild. To the best of our knowledge, there is no report on the molecular mechanisms underlying olfaction recognition in this beetle. Hence, in this study, we characterized the odorant receptor co-receptor of O. communa and named it as 'OcomORco'. Real-time quantitative PCR (qRT-PCR) showed that, compared to the control treatment, RNA interference (RNAi) strongly reduced the expression of OcomORco by 89% in male and 90% in female beetles. Electroantennogram assay showed that the antennal response of both male and female beetles to four volatiles of A. artemisiifolia was significantly reduced. The injected male or female beetles lost their preference for plant leaves as observed in the behavioural tests. In addition, disruption of the expression of OcomORco resulted in a reduction of oviposition, while there was no difference in larval hatching rate between control and knockdown females. We demonstrated that OcomORco plays a vital role in olfactory perception and host search in O. communa, and it is involved in oviposition in an indirect way.


Asunto(s)
Escarabajos/fisiología , Proteínas de Insectos/genética , Oviposición/genética , Receptores Odorantes/genética , Ambrosia/crecimiento & desarrollo , Secuencia de Aminoácidos , Animales , Escarabajos/genética , Cadena Alimentaria , Proteínas de Insectos/química , Proteínas de Insectos/metabolismo , Filogenia , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Alineación de Secuencia
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