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1.
Nature ; 603(7901): 509-514, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35264791

RESUMO

Ribosome stalling during translation is detrimental to cellular fitness, but how this is sensed and elicits recycling of ribosomal subunits and quality control of associated mRNA and incomplete nascent chains is poorly understood1,2. Here we uncover Bacillus subtilis MutS2, a member of the conserved MutS family of ATPases that function in DNA mismatch repair3, as an unexpected ribosome-binding protein with an essential function in translational quality control. Cryo-electron microscopy analysis of affinity-purified native complexes shows that MutS2 functions in sensing collisions between stalled and translating ribosomes and suggests how ribosome collisions can serve as platforms to deploy downstream processes: MutS2 has an RNA endonuclease small MutS-related (SMR) domain, as well as an ATPase/clamp domain that is properly positioned to promote ribosomal subunit dissociation, which is a requirement both for ribosome recycling and for initiation of ribosome-associated protein quality control (RQC). Accordingly, MutS2 promotes nascent chain modification with alanine-tail degrons-an early step in RQC-in an ATPase domain-dependent manner. The relevance of these observations is underscored by evidence of strong co-occurrence of MutS2 and RQC genes across bacterial phyla. Overall, the findings demonstrate a deeply conserved role for ribosome collisions in mounting a complex response to the interruption of translation within open reading frames.


Assuntos
Adenosina Trifosfatases , Ribossomos , Adenosina Trifosfatases/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Microscopia Crioeletrônica , Reparo do DNA , Biossíntese de Proteínas , Proteínas/metabolismo , Ribossomos/metabolismo
2.
Mol Psychiatry ; 29(4): 1192-1204, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38212372

RESUMO

At the center of the hippocampal tri-synaptic loop are synapses formed between mossy fiber (MF) terminals from granule cells in the dentate gyrus (DG) and proximal dendrites of CA3 pyramidal neurons. However, the molecular mechanism regulating the development and function of these synapses is poorly understood. In this study, we showed that neurotrophin-3 (NT3) was expressed in nearly all mature granule cells but not CA3 cells. We selectively deleted the NT3-encoding Ntf3 gene in the DG during the first two postnatal weeks to generate a Ntf3 conditional knockout (Ntf3-cKO). Ntf3-cKO mice of both sexes had normal hippocampal cytoarchitecture but displayed impairments in contextual memory, spatial reference memory, and nest building. Furthermore, male Ntf3-cKO mice exhibited anxiety-like behaviors, whereas female Ntf3-cKO showed some mild depressive symptoms. As MF-CA3 synapses are essential for encoding of contextual memory, we examined synaptic transmission at these synapses using ex vivo electrophysiological recordings. We found that Ntf3-cKO mice had impaired basal synaptic transmission due to deficits in excitatory postsynaptic currents mediated by AMPA receptors but normal presynaptic function and intrinsic excitability of CA3 pyramidal neurons. Consistent with this selective postsynaptic deficit, Ntf3-cKO mice had fewer and smaller thorny excrescences on proximal apical dendrites of CA3 neurons and lower GluR1 levels in the stratum lucidum area where MF-CA3 synapses reside but normal MF terminals, compared with control mice. Thus, our study indicates that NT3 expressed in the dentate gyrus is crucial for the postsynaptic structure and function of MF-CA3 synapses and hippocampal-dependent memory.


Assuntos
Região CA3 Hipocampal , Giro Denteado , Camundongos Knockout , Fibras Musgosas Hipocampais , Neurotrofina 3 , Sinapses , Animais , Giro Denteado/metabolismo , Fibras Musgosas Hipocampais/metabolismo , Sinapses/metabolismo , Camundongos , Neurotrofina 3/metabolismo , Neurotrofina 3/genética , Masculino , Feminino , Região CA3 Hipocampal/metabolismo , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Transmissão Sináptica/fisiologia , Cognição/fisiologia , Hipocampo/metabolismo , Camundongos Endogâmicos C57BL , Memória/fisiologia , Receptores de AMPA/metabolismo
3.
BMC Urol ; 24(1): 120, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858665

RESUMO

Renal cell carcinoma, a leading cause of death in urological malignancies, arises from the nephron. Its characteristics include diversity in disease biology, varied clinical behaviors, different prognoses, and diverse responses to systemic therapies. The term 'organoids' is used to describe structures resembling tissues created through the three-dimensional cultivation of stem cells in vitro. These organoids, when derived from tumor tissues, can retain the diversity of the primary tumor, mirror its spatial tissue structure, and replicate similar organ-like functions. In contrast to conventional two-dimensional cell cultures and the transplantation of tumor tissues into other organisms, organoids derived from tumors maintain the complexity and microenvironment of the original tumor tissue. This fidelity makes them a more reliable model for the development of cancer drugs, potentially accelerating the translation of these drugs to clinical use and facilitating personalized treatment options for patients. This review aims to summarize the recent advancements in the use of organoids for studying renal cell carcinoma, focusing on their cultivation, potential applications, and inherent limitations.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Organoides , Organoides/patologia , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Pesquisa Biomédica
4.
Artigo em Inglês | MEDLINE | ID: mdl-38758140

RESUMO

Objective: To analyze the role of real-time 3-dimensional echocardiography (RT-3DE) in evaluating in-stent restenosis (ISR) after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI). Methods: This study enrolled 62 AMI patients (research group) and 51 healthy volunteers (control group) who presented to The First Affiliated Hospital of Zhejiang University between October 2021 and December 2022. Differences in RT-3DE parameters between the two groups and changes in RT-3DE parameters before and after PCI in the research group were compared. The patients were followed up for 6 months after PCI to analyze the evaluation effect of RT-3DE parameters on post-PCI ISR. Results: After PCI, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), displacement standard deviation (Esd) in both groups, maximum displacement value (Emax), and LV synchronization parameters were all reduced and were higher in the study group than in the control group (P < .05). The left ventricular ejection fraction (LVEF), peak ejection rate (PER), peak filling rate (PFR), average motion amplitude (Eavg), minimum displacement value (Emin), and left ventricular synchronization parameters were all lower in the study group than in the control group (P < .05). The LVEDV and Tmsv16-SD/R-R were found to be higher in patients with ISR 6 months after PCI than in those without ISR, while LVEF and Emin were lower (P < .05). ROC curve analysis revealed that all four parameters exhibited excellent prediction efficiency for the occurrence of ISR, among which LVEF had the best performance. Conclusions: RT-3DE parameters play an excellent role in predicting the occurrence of post-PCI ISR in AMI patients.

5.
J Biomech Eng ; 142(8)2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32060536

RESUMO

To present the ligament effects on sacroiliac joint (SIJ) stability and human pelvis biomechanical characteristics in two different positions by using three-dimensional (3D) finite element (FE) models of pelvis. Based on the computed tomography (CT) data of human pelvis, three-dimensional FE models of human pelvis in sitting and standing positions were established, which include the bone (sacrum, ilium, and coccyx) and six ligaments (sacroiliac, sacrospinous, sacrotuberous, inguinal, superior pubic, and arcuate pubic ligaments). 600 N vertical load was applied at the upper surface of sacrum to analyze the stress and displacement distribution of pelvis and SIJ. The simulation results demonstrated that the maximum stresses of sacrum and ilium on SIJ contact surface were 5.63 MPa and 7.40 MPa in standing position and 7.44 MPa and 7.95 MPa in sitting position. The stresses of ligament dysfunction group were higher than that of health group, which increased by 22.6% and 35.7% in standing position and 25.2% and 43.6% in sitting position in sacrum and ilium. The maximum displacements located on the upper surface of sacrum, which were 0.13 mm and 1.04 mm in standing and sitting positions. Ligaments dysfunction group increased 30.7% and 9.6% than health group in standing and sitting positions. The integral displacement of pelvis was greater in sitting position. The location of stress concentration and displacement distribution of pelvic bone are closely resembled previous research results in two different positions. The simulation results may provide beneficial information and theoretical models for clinical research of pelvic fracture, joint movement, and ligament functional injuries, and so on.


Assuntos
Análise de Elementos Finitos , Articulação Sacroilíaca , Fenômenos Biomecânicos , Ligamentos , Pelve
6.
Int J Exp Pathol ; 98(1): 34-39, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28421649

RESUMO

The incidence of renal cell carcinoma is increasing all over the world. The molecular mechanisms for tumorigenesis, progression and prognosis are still unknown. The erythropoietin-producing hepatoma amplified sequence (Eph) receptors have been reported to be expressed aberrantly in many types of human cancers and in particular EphA5 may play a role in certain human cancers. In this study, a set of clear cell renal cell carcinoma (ccRCC) tissues were subjected to immunohistochemistry. The relationship between EphA5 protein expression and clinicopathological parameters was statistically analysed. Our data show that EphA5 protein was negatively (0) or weakly (1+) expressed in 48 of 78 (61.5%), moderately (2+) expressed in 15 of 78 (19.2%) and strongly (3+) expressed in 15 of 78 (19.2%) tumour samples of ccRCC. Decreased expression of EphA5 was detected more often in females than in males (P = 0.017, rs  = -0.267). Expression of EphA5 was related negatively to Fuhrman grade (P = 0.013, rs  = -0.279) and pathological tumour stage pT (P = 0.003, rs  = -0.334). No relation between the expression of EphA5 and age of patients was found (P = 0.107, rs  = 0.184). Fuhrman grade and pT stage are the most important factors used in prognosis of ccRCC. Hence this study may provide a new and useful prognostic marker in the clinical practice of ccRCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/metabolismo , Neoplasias Renais/metabolismo , Receptor EphA5/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/análise , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/patologia , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Renais/diagnóstico , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico
7.
Mol Cell Neurosci ; 71: 66-79, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26705735

RESUMO

Excess synapses formed during early postnatal development are pruned over an extended period, while the remaining synapses mature. Synapse pruning is critical for activity-dependent refinement of neuronal connections and its dysregulation has been found in neurodevelopmental disorders such as autism spectrum disorders; however, the mechanism underlying synapse pruning remains largely unknown. As dendritic spines are the postsynaptic sites for the vast majority of excitatory synapses, spine maturation and pruning are indicators for maturation and elimination of these synapses. Our previous studies have found that dendritically localized mRNA for brain-derived neurotrophic factor (BDNF) regulates spine maturation and pruning. Here we investigated the mechanism by which dendritic Bdnf mRNA, but not somatically restricted Bdnf mRNA, promotes spine maturation and pruning. We found that neuronal activity stimulates both translation of dendritic Bdnf mRNA and secretion of its translation product mainly as proBDNF. The secreted proBDNF promotes spine maturation and pruning, and its effect on spine pruning is in part mediated by the p75(NTR) receptor via RhoA activation. Furthermore, some proBDNF is extracellularly converted to mature BDNF and then promotes maturation of stimulated spines by activating Rac1 through the TrkB receptor. In contrast, translation of somatic Bdnf mRNA and the release of its translation product mainly as mature BDNF are independent of action potentials. These results not only reveal a biochemical pathway regulating synapse pruning, but also suggest that BDNF synthesized in the soma and dendrites is released through distinct secretory pathways.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Espinhas Dendríticas/metabolismo , Neurogênese , Potenciais de Ação , Animais , Células Cultivadas , Espinhas Dendríticas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkB/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-38439667

RESUMO

During robot-assisted reduction of pelvic fracture, blood vessels are susceptible to tensile and shear forces, making them prone to injury. Considering the impact of pelvic reduction on the risk of arterial injury, the biomechanical characteristics of arteries during the pelvic fracture reduction process are studied, and a refined coupled composite model of the damaged pelvic structure is established. Dynamic simulations of pelvic fracture reduction are conducted based on the planned reduction path. The simulation results show that during the reduction process, when the affected side is rotated, the stress and strain of the artery are maximum, particularly at the locations of the iliac common artery, internal iliac artery, and the superior gluteal artery arch endure significant stress and strain. After reduction, the maximum stress is observed in the right superior gluteal artery, and the maximum strain occurs at the intersection of the right iliac common artery. The stretch ratio of both the left and right iliac common arteries is considerable. Therefore, it can be concluded that the superior gluteal artery and the internal iliac artery are prone to injury, particularly the segment from the origin of the superior gluteal artery to its passage around the greater sciatic notch. After reduction, substantial traction on the iliac common artery, which makes it more susceptible to deformation, carries a risk of arterial rupture and aneurysm formation. This study provides a reference for planning the safe reduction path of pelvic fracture surgery and improving safety.

9.
Biomolecules ; 14(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38254691

RESUMO

The brain-derived neurotrophic factor (BDNF) and its high-affinity receptor tropomyosin-related kinase receptor B (TrkB) are widely expressed in the central nervous system. It is well documented that neurons express BDNF and full-length TrkB (TrkB.FL) as well as a lower level of truncated TrkB (TrkB.T). However, there are conflicting reports regarding the expression of BDNF and TrkB in glial cells, particularly microglia. In this study, we employed a sensitive and reliable genetic method to characterize the expression of BDNF and TrkB in glial cells in the mouse brain. We utilized three Cre mouse strains in which Cre recombinase is expressed in the same cells as BDNF, TrkB.FL, or all TrkB isoforms, and crossed them to Cre-dependent reporter mice to label BDNF- or TrkB-expressing cells with soma-localized EGFP. We performed immunohistochemistry with glial cell markers to examine the expression of BDNF and TrkB in microglia, astrocytes, and oligodendrocytes. Surprisingly, we found no BDNF- or TrkB-expressing microglia in examined CNS regions, including the somatomotor cortex, hippocampal CA1, and spinal cord. Consistent with previous studies, most astrocytes only express TrkB.T in the hippocampus of adult brains. Moreover, there are a small number of astrocytes and oligodendrocytes that express BDNF in the hippocampus, the function of which is to be determined. We also found that oligodendrocyte precursor cells, but not mature oligodendrocytes, express both TrkB.FL and TrkB.T in the hippocampus of adult mice. These results not only clarify the expression of BDNF and TrkB in glial cells but also open opportunities to investigate previously unidentified roles of BDNF and TrkB in astrocytes and oligodendrocytes.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Neuroglia , Receptor trkB , Animais , Camundongos , Astrócitos , Fator Neurotrófico Derivado do Encéfalo/genética , Microglia , Oligodendroglia , Receptor trkB/genética
10.
Oncol Lett ; 27(6): 267, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38659423

RESUMO

The high recurrence rate and poor prognosis of non-muscle invasive bladder cancer (BC) are challenges that need to be urgently addressed. Transurethral cystectomy for bladder tumors is often combined with bladder perfusion therapy, which can effectively reduce the recurrence and progression rates of BC. The present review integrated and analyzed currently available bladder perfusion drugs, mainly including chemotherapeutic agents, immunotherapeutic agents and other adjuvant perfusion drugs. Bacillus Calmette-Guerin (BCG) perfusion was the pioneering immunotherapy for early BC and still ranks high in the selection of perfusion drugs. However, BCG infusion has a high toxicity profile and has been shown to be ineffective in some patients. Due to the limitations of BCG, new bladder perfusion drugs are constantly being developed. Immunotherapeutic agents have opened a whole new chapter in the selection of therapeutic agents for bladder perfusion. The present review explored the mechanism of action, clinical dosage and adverse effects of a variety of bladder perfusion drugs currently in common use, described combined perfusion and compared the effects of certain drugs on BC.

11.
Discov Oncol ; 15(1): 111, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602556

RESUMO

Bladder cancer is one of the most frequent malignant tumors of the urinary system. The prevalence of bladder cancer among men and women is roughly 5:2, and both its incidence and death have been rising steadily over the past few years. At the moment, metastasis and recurrence of advanced bladder cancer-which are believed to be connected to the malfunction of multigene and multilevel cell signaling network-remain the leading causes of bladder cancer-related death. The therapeutic treatment of bladder cancer will be greatly aided by the elucidation of these mechanisms. New concepts for the treatment of bladder cancer have been made possible by the advancement of research technologies and a number of new treatment options, including immunotherapy and targeted therapy. In this paper, we will extensively review the development of the tumor microenvironment and the possible molecular mechanisms of bladder cancer.

12.
Cell Signal ; 115: 111011, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38104704

RESUMO

Prostate cancer is among the most common malignancies for men, with limited therapy options for last stages of the tumor. There are some different options for treatment and control of prostate tumor growth. However, targeting some specific molecules and cells within tumors has been attracted interests in recent years. The tumor microenvironment (TME) has an important role in the initiation of various malignancies, which can also expand the progression of tumor and facilitate invasion of malignant cells. By regulating immune responses and distinct changes in the metabolism of cells in the tumor, TME has substantial effects in the resistance of cancer cells to therapy. TME in various solid cancers like prostate cancer includes various cells, including cancer cells, supportive stromal cells, immunosuppressive cells, and anticancer inflammatory cells. Natural products including herbal-derived agents and also other natural compounds have been well studied for their anti-tumor potentials. These compounds may modulate various signaling pathways involved in TME, such as immune responses, the metabolism of cells, epigenetics, angiogenesis, and extracellular matrix (ECM). This paper provides a review of the current knowledge of prostate TME and complex interactions in this environment. Additionally, the potential use of natural products and also nanoparticles loaded with natural products as therapeutic adjuvants on different cells and therapeutic targets within prostate TME will be discussed.


Assuntos
Neoplasias , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Microambiente Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias/patologia
13.
J Biol Chem ; 287(29): 24739-53, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-22637477

RESUMO

Whether group VIA phospholipase A(2) (iPLA(2)ß) is involved in vascular inflammation and neointima formation is largely unknown. Here, we report that iPLA(2)ß expression increases in the vascular tunica media upon carotid artery ligation and that neointima formation is suppressed by genetic deletion of iPLA(2)ß or by inhibiting its activity or expression via perivascular delivery of bromoenol lactone or of antisense oligonucleotides, respectively. To investigate whether smooth muscle-specific iPLA(2)ß is involved in neointima formation, we generated transgenic mice in which iPLA(2)ß is expressed specifically in smooth muscle cells and demonstrate that smooth muscle-specific expression of iPLA(2)ß exacerbates ligation-induced neointima formation and enhanced both production of proinflammatory cytokines and vascular infiltration by macrophages. With cultured vascular smooth muscle cell, angiotensin II, arachidonic acid, and TNF-α markedly induce increased expression of IL-6 and TNF-α mRNAs, all of which were suppressed by inhibiting iPLA(2)ß activity or expression with bromoenol lactone, antisense oligonucleotides, and genetic deletion, respectively. Similar suppression also results from genetic deletion of 12/15-lipoxygenase or inhibiting its activity with nordihydroguaiaretic acid or luteolin. Expression of iPLA(2)ß protein in cultured vascular smooth muscle cells was found to depend on the phenotypic state and to rise upon incubation with TNF-α. Our studies thus illustrate that smooth muscle cell-specific iPLA(2)ß participates in the initiation and early progression of vascular inflammation and neointima formation and suggest that iPLA(2)ß may represent a novel therapeutic target for preventing cardiovascular diseases.


Assuntos
Cálcio/metabolismo , Inflamação/metabolismo , Músculo Liso Vascular/imunologia , Músculo Liso Vascular/metabolismo , Neointima/imunologia , Neointima/metabolismo , Fosfolipases A2 Independentes de Cálcio/metabolismo , Angiotensina II , Animais , Western Blotting , Artérias Carótidas/imunologia , Artérias Carótidas/metabolismo , Células Cultivadas , Imuno-Histoquímica , Inflamação/imunologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Oligonucleotídeos Antissenso , Fosfolipases A2 Independentes de Cálcio/genética , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Coelhos , Ratos , Ratos Sprague-Dawley
14.
Comput Methods Biomech Biomed Engin ; 26(6): 734-743, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35686483

RESUMO

For the pelvic fracture reduction, generally the fragment of the unaffected side is fixed and the affected side is moved to its correct anatomical position and orientation. During the pelvic fracture reduction, circumpelvic muscles deformation is closely related to the surgical accuracy. In this article, the biomechanical properties of musculoskeletal tissue during pelvic fracture reduction are studied. Five-parameter hyperelastic model named Mooney-Rivlin is adopted to analyze muscle's stress-strain relationship. The finite element model of the injured pelvic musculoskeletal tissue is established, and the deformation of circumpelvic main muscles is simulated. Then, the dynamic simulation of pelvic fracture reduction is performed according to the planned spatial reduction path. The results show that when the muscles are stretched the same stretch length, the strain of the gluteus medius is the largest. It is most prone to deformation under and the muscle injury is most easily to occur. During the pelvic fracture reduction, the strain of gluteus maximus is the largest, and it is most prone to deformation and injury. The traction length is the largest, and the traction force mainly comes from the gluteus maximus. This study provides reference for the robot assisted pelvic fracture reduction.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Humanos , Pelve , Fraturas Ósseas/cirurgia , Músculo Esquelético , Fixação de Fratura
15.
bioRxiv ; 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37503044

RESUMO

The brain-derived neurotrophic factor (BDNF) and its high-affinity receptor tropomyosin-related kinase receptor B (TrkB) are widely expressed in the central nervous system. It is well documented that neurons express BDNF and full-length TrkB (TrkB.FL), and a lower level of truncated TrkB (TrkB.T). With conflicting results, glial cells also have been reported to express BDNF and TrkB. In the current study, we employed a more sensitive and reliable genetic method to characterize the expression of BDNF and TrkB in glial cells in the mouse brain. We utilized three Cre mouse strains in which Cre recombinase is expressed in the same cells as BDNF, TrkB.FL, or all TrkB isoforms, and crossed them to Cre-dependent EGFP reporter mice to label BDNF- or TrkB- expressing cells. We performed immunohistochemistry with glial cell markers to examine the expression of BDNF and TrkB in microglia, astrocytes, and oligodendrocytes. Surprisingly, we found no BDNF- or TrkB- expressing microglia in the brain and spinal cord. Consistent with previous studies, most astrocytes only express TrkB.T in the adult brain. Moreover, there are a small number of astrocytes and oligodendrocytes that express BDNF, the function of which is to be determined. We also found that oligodendrocyte precursor cells, but not mature oligodendrocytes, express both TrkB.FL and TrkB.T in the adult brain. These results not only clarify the expression of BDNF and TrkB in glial cells, but also open opportunities to investigate previously unidentified roles of BDNF and TrkB in glial cells.

16.
Aging (Albany NY) ; 15(15): 7408-7423, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37433010

RESUMO

Patients with advanced bladder cancer gradually become less sensitive to chemotherapeutic agents, leading to tumor recurrence. Initiating the senescence program in solid tumors may be an important means of improving short-term drug sensitivity. The important role of c-Myc in bladder cancer cell senescence was determined using bioinformatics methods. The response to cisplatin chemotherapy in bladder cancer sample was analyzed according to the Genomics of Drug Sensitivity in Cancer database. Cell Counting Kit-8 assay, clone formation assay, and senescence-associated ß-galactosidase staining were used to assess bladder cancer cell growth, senescence, and sensitivity to cisplatin, respectively. Western blot and immunoprecipitation were performed to understand the regulation of p21 by c-Myc/HSP90B1. Bioinformatic analysis showed that c-Myc, a cellular senescence gene, was significantly associated with bladder cancer prognosis and sensitivity to cisplatin chemotherapy. c-Myc and HSP90B1 expression were highly correlated in bladder cancer. Reducing the level of c-Myc significantly inhibited bladder cancer cell proliferation, promoted cellular senescence, and enhanced cisplatin chemosensitivity. Immunoprecipitation assays confirmed that HSP90B1 interacted with c-Myc. Western blot analysis showed that reducing the level of HSP90B1 could redeem the p21 overexpression caused by c-Myc overexpression. Further studies showed that reducing HSP90B1 expression could alleviate the rapid growth and accelerate cellular senescence of bladder cancer cells caused by c-Myc overexpression, and that reducing HSP90B1 levels could also improve cisplatin sensitivity in bladder cancer cells. HSP90B1/c-Myc interaction regulates the p21 signaling pathway, which affects cisplatin chemosensitivity by modulating bladder cancer cell senescence.


Assuntos
Antineoplásicos , Neoplasias da Bexiga Urinária , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Recidiva Local de Neoplasia/genética , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Proliferação de Células/genética , Senescência Celular/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
17.
J Colloid Interface Sci ; 640: 549-557, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36878072

RESUMO

High activity, excellent durability, and low-cost oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts are highly required for rechargeable zinc (Zn)-air batteries. Herein, we designed an electrocatalyst by integrating the ORR active species of ferroferric oxide (Fe3O4) and the OER active species of cobaltous oxide (CoO) into the carbon nanoflower. By well regulating and controlling the synthesis parameters, Fe3O4 and CoO nanoparticles were uniformly inserted into the porous carbon nanoflower. This electrocatalyst can reduce the potential gap between the ORR and OER to 0.79 V. The Zn-air battery assembled with it exhibited an open-circuit voltage of 1.457 V, a stable discharge of 98 h, a high specific capacity of 740 mA h g-1, a large power density of 137 mW cm-2, as well as good charge/discharge cycling performance, exceeding the performance of platinum/carbon (Pt/C). This work provides references for exploring highly efficient non-noble metal oxygen electrocatalysts by tuning ORR/OER active sites.

18.
SLAS Discov ; 28(3): 88-94, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36842668

RESUMO

Deficiencies in brain-derived neurotrophic factor (BDNF) have been linked to several brain disorders, making compounds that can boost neuronal BDNF synthesis attractive as potential therapeutics. However, a sensitive and quantitative BDNF assay for high-throughput screening (HTS) is still missing. Here we report the generation of a new mouse Bdnf allele, BdnfNLuc, in which the sequence encoding nano luciferase (NLuc) is inserted into the Bdnf locus immediately before the stop codon so that the allele will produce a BDNF-NLuc fusion protein. BDNF-NLuc protein appears to function like BDNF as BdnfNLuc/NLuc homozygous mice grew and behaved almost normally. We were able to establish and optimize cultures of cortical and hippocampal BdnfNLuc/+ neurons isolated from mouse embryos in 384-well plates. We used the cultures as a phenotypic assay to detect the ability of 10 mM KCl to stimulate BDNF synthesis and achieved a reproducible Z' factor > 0.50 for the assay, a measure considered suitable for HTS. We successfully scaled up the assay to screen the 1280-compound LOPAC library (Library of Pharmacologically Active Compounds). The screen identified several BDNF-boosting compounds, one of which is Bay K8644, a L-type voltage-gated calcium channel (L-VGCC) agonist, which was previously shown to stimulate BDNF synthesis. These results indicate that our phenotypic neuronal assay is ready for HTS to identify novel BDNF-boosting compounds.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Ensaios de Triagem em Larga Escala , Camundongos , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Neurônios/metabolismo , Canais de Cálcio Tipo L/metabolismo , Encéfalo/metabolismo
19.
Int J Med Robot ; 18(2): e2361, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34969160

RESUMO

BACKGROUND: For the robot-assisted fracture reduction, due to the complex fracture musculoskeletal environment, it is necessary to consider the influence of soft tissue traction on preoperative reduction path planning. METHOD: An improved 3D A* algorithm is adopted to plan the fracture reduction path. The distal fragment point clouds are updated to avoid the collision, and the end point coordinates of the muscles are updated to calculate muscular lengths during the path search. RESULTS: 3D reduction path of long-bone fracture is planned, effectively avoiding the fracture fragments collision and ensuring the length of the corresponding muscle is always less than the allowable maximum muscle length after elongation. CONCLUSION: The proposed method can effectively avoid the collision between the distal fragment and the proximal fragment during the fracture reduction, can avoid secondary injury of the muscles around the femoral bone caused by over-distraction, and effectively improve the safety of robot reduction operation.


Assuntos
Fraturas Ósseas , Robótica , Fixação de Fratura , Fraturas Ósseas/cirurgia , Humanos , Músculos , Tração
20.
Cancers (Basel) ; 14(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36230661

RESUMO

BACKGROUND: Long noncoding RNAs regulate various biological effects in the progression of cancers. We found that the expression of SNHG1 was significantly up-regulated in bladder cancer after analyzing data obtained from TCGA and GEO. However, the potential role of SNHG1 remains to be investigated in bladder cancer. It was validated that SNHG1 was overexpressed in bladder cancer tissues detected by qRT-PCR and FISH, which was also associated with poor clinical outcome. Additionally, SNHG1 was verified to facilitate tumor proliferation and repress apoptosis in vitro and in vivo. RESULTS: SNHG1 could act as a competitive endogenous RNA and decrease the expression of murine double minute 2 (MDM2) by sponging microRNA-9-3p. Furthermore, MDM2 induced ubiquitination and degradation of PPARγ that contributed to the development of bladder cancer. CONCLUSIONS: the study elucidated that SNHG1 played an important role in bladder cancer and provided a potential therapeutic target for bladder cancer.

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