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1.
Mol Cell ; 82(2): 479-491.e7, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-34963054

RESUMO

Genetically encoded biosensors are powerful tools to monitor cellular behavior, but the difficulty in generating appropriate reporters for chromatin factors hampers our ability to dissect epigenetic pathways. Here, we present TRACE (transgene reporters across chromatin environments), a high-throughput, genome-wide technique to generate fluorescent human reporter cell lines responsive to manipulation of epigenetic factors. By profiling GFP expression from a large pool of individually barcoded lentiviral integrants in the presence and absence of a perturbation, we identify reporters responsive to pharmacological inhibition of the histone lysine demethylase LSD1 and genetic ablation of the PRC2 subunit SUZ12. Furthermore, by manipulating the HIV-1 host factor LEDGF through targeted deletion or fusion to chromatin reader domains, we alter lentiviral integration site preferences, thus broadening the types of chromatin examined by TRACE. The phenotypic reporters generated through TRACE will allow the genetic interrogation of a broad range of epigenetic pathways, furthering our mechanistic understanding of chromatin biology.


Assuntos
Técnicas Biossensoriais , Epigênese Genética , Genes Reporter , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Lentivirus/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Montagem e Desmontagem da Cromatina , Epigenoma , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células HeLa , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Lentivirus/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Células THP-1 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Mol Cell ; 74(6): 1138-1147.e6, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-30982744

RESUMO

Adenine N6 methylation in DNA (6mA) is widespread among bacteria and phage and is detected in mammalian genomes, where its function is largely unexplored. Here we show that 6mA deposition and removal are catalyzed by the Mettl4 methyltransferase and Alkbh4 dioxygenase, respectively, and that 6mA accumulation in genic elements corresponds with transcriptional silencing. Inactivation of murine Mettl4 depletes 6mA and causes sublethality and craniofacial dysmorphism in incross progeny. We identify distinct 6mA sensor domains of prokaryotic origin within the MPND deubiquitinase and ASXL1, a component of the Polycomb repressive deubiquitinase (PR-DUB) complex, both of which act to remove monoubiquitin from histone H2A (H2A-K119Ub), a repressive mark. Deposition of 6mA by Mettl4 triggers the proteolytic destruction of both sensor proteins, preserving genome-wide H2A-K119Ub levels. Expression of the bacterial 6mA methyltransferase Dam, in contrast, fails to destroy either sensor. These findings uncover a native, adversarial 6mA network architecture that preserves Polycomb silencing.


Assuntos
Adenina/análogos & derivados , Homólogo AlkB 4 da Lisina Desmetilase/genética , Anormalidades Craniofaciais/genética , DNA/genética , Metiltransferases/genética , Proteínas Repressoras/genética , Adenina/metabolismo , Homólogo AlkB 4 da Lisina Desmetilase/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Anormalidades Craniofaciais/metabolismo , Anormalidades Craniofaciais/patologia , DNA/metabolismo , Metilação de DNA , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/metabolismo , Feminino , Inativação Gênica , Genes Letais , Histonas/genética , Histonas/metabolismo , Endogamia , Masculino , Metiltransferases/deficiência , Camundongos , Camundongos Knockout , Proteólise , Proteínas Repressoras/metabolismo , Transdução de Sinais , DNA Metiltransferases Sítio Específica (Adenina-Específica)/genética , DNA Metiltransferases Sítio Específica (Adenina-Específica)/metabolismo , Transcrição Gênica , Ubiquitina/genética , Ubiquitina/metabolismo
3.
FASEB J ; 38(5): e23501, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38411462

RESUMO

In the adult mammalian brain, new neurons are continuously generated from neural stem cells (NSCs) in the subventricular zone (SVZ)-olfactory bulb (OB) pathway. YAP, a transcriptional co-activator of the Hippo pathway, promotes cell proliferation and inhibits differentiation in embryonic neural progenitors. However, the role of YAP in postnatal NSCs remains unclear. Here, we showed that YAP was present in NSCs of the postnatal mouse SVZ. Forced expression of Yap promoted NSC maintenance and inhibited differentiation, whereas depletion of Yap by RNA interference or conditional knockout led to the decline of NSC maintenance, premature neuronal differentiation, and collapse of neurogenesis. For the molecular mechanism, thyroid hormone receptor-interacting protein 6 (TRIP6) recruited protein phosphatase PP1A to dephosphorylate LATS1/2, therefore inducing YAP nuclear localization and activation. Moreover, TRIP6 promoted NSC maintenance, cell proliferation, and inhibited differentiation through YAP. In addition, YAP regulated the expression of the Sonic Hedgehog (SHH) pathway effector Gli2 and Gli1/2 mediated the effect of YAP on NSC maintenance. Together, our findings demonstrate a novel TRIP6-YAP-SHH axis, which is critical for regulating postnatal neurogenesis in the SVZ-OB pathway.


Assuntos
Proteínas Hedgehog , Células-Tronco Neurais , Animais , Camundongos , Neurônios , Neurogênese , Encéfalo , Mamíferos
4.
J Pathol ; 263(4-5): 466-481, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38924548

RESUMO

The E3 ubiquitin ligase thyroid hormone receptor interacting protein 12 (TRIP12) has been implicated in pancreatic adenocarcinoma (PDAC) through its role in mediating the degradation of pancreas transcription factor 1a (PTF1a). PTF1a is a transcription factor essential for the acinar differentiation state that is notably diminished during the early steps of pancreatic carcinogenesis. Despite these findings, the direct involvement of TRIP12 in the onset of pancreatic cancer has yet to be established. In this study, we demonstrated that TRIP12 protein was significantly upregulated in human pancreatic preneoplastic lesions. Furthermore, we observed that TRIP12 overexpression varied within PDAC samples and PDAC-derived cell lines. We further demonstrated that TRIP12 was required for PDAC-derived cell growth and for the expression of E2F-targeted genes. Acinar-to-ductal cell metaplasia (ADM) is a reversible process that reflects the high plasticity of acinar cells. ADM becomes irreversible in the presence of oncogenic Kras mutations and leads to the formation of preneoplastic lesions. Using two genetically modified mouse models, we showed that a loss of TRIP12 prevented acini from developing ADM in response to pancreatic injury. With two additional mouse models, we further discovered that a depletion of TRIP12 prevented the formation of KrasG12D-induced preneoplastic lesions and impaired metastasis formation in the presence of mutated KrasG12D and Trp53R172H genes. In summary our study identified an overexpression of TRIP12 from the early stages of pancreatic carcinogenesis and proposed this E3 ubiquitin ligase as a novel regulator of acinar plasticity with an important dual role in initiation and metastatic steps of PDAC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Assuntos
Células Acinares , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ubiquitina-Proteína Ligases , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/enzimologia , Humanos , Células Acinares/patologia , Células Acinares/metabolismo , Células Acinares/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/enzimologia , Metaplasia/patologia , Metaplasia/metabolismo , Plasticidade Celular , Carcinogênese/genética , Carcinogênese/metabolismo , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Camundongos Knockout , Regulação Neoplásica da Expressão Gênica , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/enzimologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/metabolismo , Proteínas de Transporte
5.
Cancer Immunol Immunother ; 73(4): 69, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430268

RESUMO

BACKGROUND: Investigations elucidating the complex immunological mechanisms involved in colorectal cancer (CRC) and accurately predicting patient outcomes via bulk RNA-Seq analysis have been notably limited. This study aimed to identify the immune status of CRC patients, construct a prognostic model, and identify prognostic signatures via bulk RNA sequencing (RNA-seq) and single-cell RNA-seq (scRNA-seq). METHODS: The scRNA-seq data of CRC were downloaded from Gene Expression Omnibus (GEO). The UCSC Xena database was used to obtain bulk RNA-seq data. Differentially expressed gene (DEG), functional enrichment, and random forest analyses were conducted in order to identify core genes associated with colorectal cancer (CRC) that were relevant to prognosis. A molecular immune prediction model was developed using logistic regression after screening features using the least absolute shrinkage and selection operator (LASSO). The differences in immune cell infiltration, mutation, chemotherapeutic drug sensitivity, cellular senescence, and communication between patients who were at high and low risk of CRC according to the predictive model were investigated. The prognostic genes that were closely associated with CRC were identified by random survival forest (RSF) analysis. The expression levels and clinical significance of the hub genes were analyzed in vitro. The LoVo cell line was employed to ascertain the biological role of thyroid hormone receptor-interacting protein 6 (TRIP6). RESULTS: A total of seven main cell subtypes were identified by scRNA-seq analysis. A molecular immune predictive model was constructed based on the risk scores. The risk score was significantly associated with OS, stage, mutation burden, immune cell infiltration, response to immunotherapy, key pathways, and cell-cell communication. The functions of the six hub genes were determined and further utilized to establish a regulatory network. Our findings unequivocally confirmed that TRIP6 upregulation was verified in the CRC samples. After knocking down TRIP6, cell proliferation, migration, and invasion of LoVo cells were inhibited, and apoptosis was promoted. CONCLUSIONS: The molecular predictive model reliably distinguished the immune status of CRC patients. We further revealed that TRIP6 may act as an oncogene in CRC, making it a promising candidate for targeted therapy and as a prognostic marker for CRC.


Assuntos
Neoplasias Colorretais , Imunoterapia , Humanos , Proteínas Adaptadoras de Transdução de Sinal , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia , Proteínas com Domínio LIM , Prognóstico , RNA-Seq , Análise de Sequência de RNA , Fatores de Transcrição
6.
Bioorg Med Chem Lett ; 98: 129590, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38092072

RESUMO

Natural product cantharidin can inhibit multiple myeloma cell growth in vitro, while serious adverse effects limited its clinical application. Therefore, the structural modification of cantharidin is needed. Herein, inspired by the structural similarity of the aliphatic endocyclic moiety in cantharidin and TRIP13 inhibitor DCZ0415, we designed and synthesized DCZ5418 and its nineteen derivatives. The molecular docking study indicated that DCZ5418 had a similar binding mode to TRIP13 protein as DCZ0415 while with a stronger docking score. Moreover, the bioassay studies of the MM-cells viability inhibition, TRIP13 protein binding affinity and enzyme inhibiting activity showed that DCZ5418 had good anti-MM activity in vitro and definite interaction with TRIP13 protein. The acute toxicity test of DCZ5418 showed less toxicity in vivo than cantharidin. Furthermore, DCZ5418 showed good anti-MM effects in vivo with a lower dose administration than DCZ0415 (15 mg/kg vs 25 mg/kg) on the tumor xenograft models. Thus, we obtained a new TRIP13 inhibitor DCZ5418 with improved safety and good activity in vivo, which provides a new example of lead optimization by using the structural fragments of natural products.


Assuntos
Cantaridina , Mieloma Múltiplo , Humanos , ATPases Associadas a Diversas Atividades Celulares/antagonistas & inibidores , Cantaridina/farmacologia , Cantaridina/uso terapêutico , Cantaridina/química , Proteínas de Ciclo Celular , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Simulação de Acoplamento Molecular , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia
7.
Exp Brain Res ; 242(2): 505-519, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38197941

RESUMO

Understanding why falls during pregnancy occur at over 25% rate over gestation has clinical impacts on the health of pregnant individuals. Attention, proprioception, and perception of the environment are required to prevent trips and falls. This research aimed to understand how the changes to these neurocognitive processes control obstacle avoidance through gestation. Seventeen pregnant participants were tested five times in 6-week intervals. Participants walked an obstacle course (OC), and we analyzed the crossings over obstacles that were set to 10% of participants' body height. Participants also performed an attentional network test (ANT: performance of specific components of attention), an obstacle perception task (OP: ability to visually define an obstacle and translate that to a body posture), and a joint position sense task (JPS: ability to recognize and recreate a joint position from somatosensation). In the OC task, average leading and trailing foot crossing heights significantly reduced by 13% and 23% respectively, with no change in variation, between weeks 13 and 31 of pregnancy, indicating an increased risk of obstacle contact during this time. The variability in minimum leading foot distances from the obstacle was correlated with all three neurocognition tasks (ANT, OP, and JPS). Increased fall rates in the second and third trimesters of pregnancy may be driven by changes in attention, with additional contributions of joint position sense and environmental perception at various stages of gestation. The results imply that a holistic examination on an individual basis may be required to determine individual trip risk and appropriate safety modifications.


Assuntos
Atenção , Caminhada , Humanos , Gravidez , Feminino , , Propriocepção , Marcha , Fenômenos Biomecânicos
8.
Bioorg Med Chem ; 111: 117843, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39083980

RESUMO

This study reported the design and synthesis of novel 1-amido-2-one-4-thio-deoxypyranose as inhibitors of potential drug target TRIP13 for developing new mechanism-based therapeutic agents in the treatment of multiple myeloma (MM). In comparison with the positive control DCZ0415, the most active compounds C16, C18, C20 and C32 exhibited strong anti-proliferative activity against human MM cell lines (ARP-1 and NCI-H929) with IC50 values of 1 âˆ¼ 2 µM. While the surface plasmon resonance (SPR) and ATPase activity assays demonstrated that the representative compound C20 is a potent inhibitor of TRIP13, C20 also showed good antitumor activity in vivo on BALB/c nude mice xenografted with MM tumor cells. An initial structure-activity study showed that the carbonyl group is crucial for anticancer activity. Overall, this study provided novel 1-amido-2-one-4-thio-deoxypyranoses, which are entirely different from previously reported potent inhibitor structures of TRIP13, and thus would aid the development of carbohydrate-based novel agents in MM pharmacotherapy.


Assuntos
Antineoplásicos , Proliferação de Células , Desenho de Fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mieloma Múltiplo , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Animais , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Mieloma Múltiplo/metabolismo , Relação Estrutura-Atividade , Camundongos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Relação Dose-Resposta a Droga , Tanquirases
9.
Bioorg Chem ; 151: 107650, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39042962

RESUMO

ATPases Associated with Diverse Cellular Activity (AAA+ATPases) are important enzymatic functional proteins in human cells. Thyroid Hormone Receptor Interacting Protein-13 (TRIP13) is a member of this protein superfamily, that partly regulates DNA repair pathways and spindle assembly checkpoints during mitosis. TRIP13 is reported as an oncogene involving multiple pathways in many human malignancies, including multiple myeloma, brain tumors, etc. The structure of TRIP13 reveals the mechanisms for ATP binding and how TRIP13 recognizes the Mitotic Arrest Deficiency-2 (MAD2) protein, with p31comet acting as an adapter protein. DCZ0415, TI17, DCZ5417, and DCZ5418 are the reported small-molecule inhibitors of TRIP13, which have been demonstrated to inhibit TRIP13's biological functions significantly and effective in suppressing various types of malignant cells, indicating that TRIP13 is a significant anticancer drug target. Currently, no systematic reviews are cutting across the functions, structure, and novel inhibitors of TRIP13. This review provides a comprehensive overview of TRIP13's biological functions, its roles in eighteen different cancers, four small molecule inhibitors, different underlying molecular mechanisms, and its functionality as a potential anticancer drug target.


Assuntos
ATPases Associadas a Diversas Atividades Celulares , Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , ATPases Associadas a Diversas Atividades Celulares/antagonistas & inibidores , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Bibliotecas de Moléculas Pequenas/síntese química , Relação Estrutura-Atividade , Proteínas de Ciclo Celular
10.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33597306

RESUMO

The Shieldin complex, composed of REV7, SHLD1, SHLD2, and SHLD3, protects DNA double-strand breaks (DSBs) to promote nonhomologous end joining. The AAA+ ATPase TRIP13 remodels Shieldin to regulate DNA repair pathway choice. Here we report crystal structures of human SHLD3-REV7 binary and fused SHLD2-SHLD3-REV7 ternary complexes, revealing that assembly of Shieldin requires fused SHLD2-SHLD3 induced conformational heterodimerization of open (O-REV7) and closed (C-REV7) forms of REV7. We also report the cryogenic electron microscopy (cryo-EM) structures of the ATPγS-bound fused SHLD2-SHLD3-REV7-TRIP13 complexes, uncovering the principles underlying the TRIP13-mediated disassembly mechanism of the Shieldin complex. We demonstrate that the N terminus of REV7 inserts into the central channel of TRIP13, setting the stage for pulling the unfolded N-terminal peptide of C-REV7 through the central TRIP13 hexameric channel. The primary interface involves contacts between the safety-belt segment of C-REV7 and a conserved and negatively charged loop of TRIP13. This process is mediated by ATP hydrolysis-triggered rotatory motions of the TRIP13 ATPase, thereby resulting in the disassembly of the Shieldin complex.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Mad2/metabolismo , ATPases Associadas a Diversas Atividades Celulares/química , Proteínas de Ciclo Celular/química , Proteínas de Ligação a DNA/química , Humanos , Hidrólise , Proteínas Mad2/química , Modelos Moleculares , Conformação Proteica
11.
Biochem Genet ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430448

RESUMO

Globally, colorectal cancer (CRC) is one of the leading causes of health problems. More reliable molecular biomarkers for early diagnosis in CRC patients are needed. A crucial role for thyroid hormone receptor interacting protein 6 (TRIP6) is played in tumorigenesis and tumor growth. Our study aims to determine the diagnostic and prognostic roles of TRIP6 at CRC. TRIP6 gene expression levels were analyzed in this study from public databases. The relationship between TRIP6 expression and clinicopathological characteristics was explored by logistic regression analysis. Based on Kaplan-Meier (K-M) survival curves and receiver operating characteristic curves (ROC) analysis, the prognostic and diagnostic values of TRIP6 were determined. Protein-protein interaction (PPI) networks analysis were performed using the STRING database. A Spearman's correlation analysis applied for examining the correlation between TRIP6 expression, immune cell infiltration, and immune checkpoint genes. Moreover, colony formation assay and transwell assay were used to investigate the functions of TRIP6. TRIP6 was highly expressed in CRC cancer tissues and cells. K-M survival analysis indicated that a high expression of TRIP6 was associated with poor prognosis. TRIP6 expression was obviously associated with immune cell infiltration and immune checkpoint gene expression. For validation, the results of collected clinical CRC samples show that TRIP6 levels in CRC tumor tissue were higher than those of paired adjacent colorectal tissues. Additionally, in vitro experiments suggested that TRIP6 knockdown suppressed proliferation and migration in CRC cell line RKO. TRIP6 overexpression promoted the proliferation and migration of normal colon cell line NCM460. High TRIP6 expression is associated with poor prognosis in colorectal cancer and promotes tumor cell proliferation and migration which may be a potential diagnostic and prognostic biomarker and a promising therapeutic target for CRC, providing new insights into its role in CRC.

12.
Artigo em Inglês | MEDLINE | ID: mdl-39297991

RESUMO

PURPOSE: As a cause of primary female infertility, oocyte maturation arrest (OMA) is characterized by failure to obtain mature oocytes due to abnormal meiosis. We aimed to identify pathogenic variants in two sisters with OMA phenotype from a non-consanguineous family. METHODS: Whole-exome sequencing and Sanger sequencing were conducted to identify and validate the disease-causing gene variant. Additionally, we performed a minigene assay, quantitative reverse transcription PCR, and Western blotting to assess the effects of the variant. RESULTS: We identified a novel homozygous splicing variant (c.1021-11T>C) in TRIP13, which followed a recessive inheritance pattern. Minigene assay showed that the variant could disrupt the integrity of TRIP13 mRNA, as evidenced by the production of an alternative transcript with intron10 intermediate retention of 79 bp. Compared to normal controls, the expression of TRIP13 mRNA and abundance of TRIP13 protein were also significantly decreased in Epstein-Barr virus-immortalized lymphoblastoid cells derived from affected individuals. CONCLUSION: Our findings confirm the contribution of genetic factors to OMA and expand the mutation spectrum of TRIP13 in female infertility.

13.
J Neuroeng Rehabil ; 21(1): 117, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003469

RESUMO

BACKGROUND: Falls due to stumbling are prevalent for transfemoral prosthesis users and may lead to increased injury risk. This preliminary case series analyzes the transfemoral prosthesis user stumble recovery response to highlight key deficits in current commercially-available prostheses and proposes potential interventions to improve recovery outcomes. METHODS: Six transfemoral prosthesis users were perturbed on their prosthetic limb at least three times while walking on a treadmill using obstacle perturbations in early, mid and late swing. Kinematic data were collected to characterize the response, while fall rate and key kinematic recovery metrics were used to assess the quality of recovery and highlight functional deficits in current commercially-available prostheses. RESULTS: Across all participants, 13 (54%) of the 24 trials resulted in a fall (defined as > 50% body-weight support) with all but one participant (83%) falling at least once and two participants (33%) falling every time. In contrast, in a previous study of seven young, unimpaired, non-prosthesis users using the same experimental apparatus, no falls occurred across 190 trials. For the transfemoral prosthesis users, early swing had the highest rate of falling at 64%, followed by mid-swing at 57%, and then late swing at 33%. The trend in falls was mirrored by the kinematic recovery metrics (peak trunk angle, peak trunk angular velocity, forward reach of the perturbed limb, and knee angle at ground contact). In early swing all four metrics were deficient compared to non-prosthesis user controls. In mid swing, all but trunk angular velocity were deficient. In late swing only forward reach was deficient. CONCLUSION: Based on the stumble recovery responses, four potential deficiencies were identified in the response of the knee prostheses: (1) insufficient resistance to stance knee flexion upon ground contact; (2) insufficient swing extension after a perturbation; (3) difficulty initiating swing flexion following a perturbation; and (4) excessive impedance against swing flexion in early swing preventing the potential utilization of the elevating strategy. Each of these issues can potentially be addressed by mechanical or mechatronic changes to prosthetic design to improve quality of recovery and reduce the likelihood a fall.


Assuntos
Acidentes por Quedas , Membros Artificiais , Humanos , Acidentes por Quedas/prevenção & controle , Membros Artificiais/efeitos adversos , Masculino , Feminino , Fenômenos Biomecânicos , Adulto , Pessoa de Meia-Idade , Caminhada/fisiologia , Fêmur/fisiologia , Amputados/reabilitação , Marcha/fisiologia
14.
Sensors (Basel) ; 24(16)2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39205074

RESUMO

Slip, trip, and fall (STF) accidents cause high rates of absence from work in many companies. During the 2022 reporting period, the German Social Accident Insurance recorded 165,420 STF accidents, of which 12 were fatal and 2485 led to disability pensions. Particularly in the traffic, transport and logistics sector, STF accidents are the most frequently reported occupational accidents. Therefore, an accurate detection of near-falls is critical to improve worker safety. Efficient detection algorithms are essential for this, but their performance heavily depends on large, well-curated datasets. However, there are drawbacks to current datasets, including small sample sizes, an emphasis on older demographics, and a reliance on simulated rather than real data. In this paper we report the collection of a standardised kinematic STF dataset from real-world STF events affecting parcel delivery workers and steelworkers. We further discuss the use of the data to evaluate dynamic stability control during locomotion for machine learning and build a standardised database. We present the data collection, discuss the classification of the data, present the totality of the data statistically, and compare it with existing databases. A significant research gap is the limited number of participants and focus on older populations in previous studies, as well as the reliance on simulated rather than real-world data. Our study addresses these gaps by providing a larger dataset of real-world STF events from a working population with physically demanding jobs. The population studied included 110 participants, consisting of 55 parcel delivery drivers and 55 steelworkers, both male and female, aged between 19 and 63 years. This diverse participant base allows for a more comprehensive understanding of STF incidents in different working environments.


Assuntos
Acidentes por Quedas , Algoritmos , Marcha , Aprendizado de Máquina , Humanos , Marcha/fisiologia , Fenômenos Biomecânicos/fisiologia , Masculino , Adulto , Acidentes por Quedas/prevenção & controle , Feminino , Pessoa de Meia-Idade , Acidentes de Trabalho , Adulto Jovem , Bases de Dados Factuais
15.
Transp Res Part A Policy Pract ; 181: 104007, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463220

RESUMO

This paper examines the endogenous relationship between residential level of accessibility and household trip frequencies to tease out the direct and indirect effects of observed behavioural differences. We estimate a multivariate ordered probit model system, which allows dependence in both observed and unobserved factors, using data from the 2016 Transportation Tomorrow Survey (TTS), a household travel survey in the Greater Golden Horseshoe Area (GGH) in Toronto. The modelling framework is used to analyse the influence of exogenous variables on eight outcome variables of accessibility levels and trip frequencies by four modes (auto, transit, bicycle and walk), and to explore the nature of the relationships between them. The results confirm our hypothesis that not only does a strong correlation exist between the residential level of accessibility and household trip frequency, but there are also direct effects to be observed. The complementarity effect between auto accessibility and transit trips, and the substitution effect observed between transit accessibility and auto trips highlight the residential neighbourhood dissonance of transit riders. It shows that locations with better transit service are not necessarily locations where people who make more transit trips reside. Essentially, both jointness (due to error correlations) as well as directional effects observed between accessibility and trip frequencies of multiple modes offer strong support for the notion that accessibility and trip frequency by mode constitute a bundled choice and need to be considered as such.

16.
Artigo em Alemão | MEDLINE | ID: mdl-39012368

RESUMO

For older people, a sufficient mobility offer is an essential prerequisite for participation in social life and a better quality of life. The goal should be self-determined everyday mobility that enables a satisfying and healthy life. Mobility depends on diverse individual abilities and needs. On the other hand, social structures as well as regulatory and spatial framework conditions limit the realisation of mobility services and their transport infrastructure. These framework conditions are characterised by the perception of social roles, the availability of resources and gender-specific attributions. For example, care and caring work is predominantly the responsibility of women in the age group of 50 years plus. The availability of transport infrastructure is geared towards goals that are characterised by the needs of gainful employment and not the goals of care work. Conversely, the availability of flexible means of transport, such as cars, also decreases for women in old age for economic reasons. For this reason, mobility planning should take greater account of specific needs, such as orientation towards care objectives, counselling, and health services and place a greater focus on the local area. For elderly people, especially women, security needs are often an important factor in the decision to become mobile or to forego mobility. This includes perceived subjective safety, accessibility and protection from weather conditions such as slippery surfaces or exposure to excessive heat. If these basic principles are taken into account, more people can be guaranteed self-determined participation in social life.


Assuntos
Limitação da Mobilidade , Humanos , Alemanha , Feminino , Idoso , Masculino , Idoso de 80 Anos ou mais , Distribuição por Sexo , Pessoa de Meia-Idade
17.
Angew Chem Int Ed Engl ; 63(17): e202400132, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38409997

RESUMO

Li-CO2 batteries have received significant attention owing to their advantages of combining greenhouse gas utilization and energy storage. However, the high kinetic barrier between gaseous CO2 and the Li2CO3 product leads to a low operating voltage (<2.5 V) and poor energy efficiency. In addition, the reversibility of Li2CO3 has always been questioned owing to the introduction of more decomposition paths caused by its higher charging plateau. Here, a novel "trinity" Li-CO2 battery system was developed by synergizing CO2, soluble redox mediator (2,2,6,6-tetramethylpiperidoxyl, as TEM RM), and reduced graphene oxide electrode to enable selective conversion of CO2 to Li2C2O4. The designed Li-CO2 battery exhibited an output plateau reaching up to 2.97 V, higher than the equilibrium potential of 2.80 V for Li2CO3, and an ultrahigh round-trip efficiency of 97.1 %. The superior performance of Li-CO2 batteries is attributed to the TEM RM-mediated preferential growth mechanism of Li2C2O4, which enhances the reaction kinetics and rechargeability. Such a unique design enables batteries to cope with sudden CO2-deficient environments, which provides an avenue for the rationally design of CO2 conversion reactions and a feasible guide for next-generation Li-CO2 batteries.

18.
J Biol Chem ; 298(7): 102069, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35623388

RESUMO

Major depressive disorder is a critical public health problem with a lifetime prevalence of nearly 17% in the United States. One potential therapeutic target is the interaction between hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and an auxiliary subunit of the channel named tetratricopeptide repeat-containing Rab8b-interacting protein (TRIP8b). HCN channels regulate neuronal excitability in the mammalian hippocampus, and recent work has established that antagonizing HCN function rescues cognitive impairment caused by chronic stress. Here, we utilize a high-throughput virtual screen to find small molecules capable of disrupting the TRIP8b-HCN interaction. We found that the hit compound NUCC-0200590 disrupts the TRIP8b-HCN interaction in vitro and in vivo. These results provide a compelling strategy for developing new small molecules capable of disrupting the TRIP8b-HCN interaction.


Assuntos
Transtorno Depressivo Maior , Animais , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Transtorno Depressivo Maior/metabolismo , Hipocampo/metabolismo , Humanos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Mamíferos/metabolismo , Neurônios/metabolismo
19.
Funct Integr Genomics ; 23(3): 232, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37432513

RESUMO

TRIP13 is highly expressed in various human tumors and promotes tumorigenesis. We aimed to explore the biological effect of TRIP13 on gastric cancer. The RNA sequence data were retrieved from TCGA to evaluate TRIP13 mRNA expression in gastric cancer. Paired formalin-fixed paraffin-embedded blocks were further analyzed to verify the relationship between TRIP13 expression and carcinogenic status. The functions of TRIP13 on the proliferation of gastric malignancy were investigated by MTT, flow cytometry, colony formation experiment, and nude mouse tumor formation experiment. Finally, microarray analysis of TRIP13-related pathways was performed to identify the potential underlying mechanism of TRIP13 in gastric cancer. TRIP13 was found to have high expression in tumor samples. TRIP13 expression status was significantly subjective to tumor-node-metastasis (TNM) staging and poor survival. The downregulation of TRIP13 promoted apoptosis and inhibited tumor growth. TRIP13-dependent JAK/STAT and NF-κB signaling cascade were found as two key pathways in the carcinogenesis of GC. In conclusion, TRIP13 participates in the carcinogenesis of stomach cancer, and its overexpression in the cancerous tissues dovetail with advanced stage and survival. Moreover, TRIP13 functions as an upstream regulator of the JAK/STAT and p53 signaling pathways, which play critical roles in developing various malignancies.


Assuntos
Neoplasias Gástricas , Humanos , Animais , Camundongos , Neoplasias Gástricas/genética , Carcinogênese/genética , Regulação para Baixo , Apoptose , NF-kappa B , ATPases Associadas a Diversas Atividades Celulares , Proteínas de Ciclo Celular
20.
Am J Hum Genet ; 107(1): 15-23, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32473092

RESUMO

Normal oocyte meiosis is a prerequisite for successful human reproduction, and abnormalities in the process will result in infertility. In 2016, we identified mutations in TUBB8 as responsible for human oocyte meiotic arrest. However, the underlying genetic factors for most affected individuals remain unknown. TRIP13, encoding an AAA-ATPase, is a key component of the spindle assembly checkpoint, and recurrent homozygous nonsense variants and a splicing variant in TRIP13 are reported to cause Wilms tumors in children. In this study, we identified homozygous and compound heterozygous missense pathogenic variants in TRIP13 responsible for female infertility mainly characterized by oocyte meiotic arrest in five individuals from four independent families. Individuals from three families suffered from oocyte maturation arrest, whereas the individual from the fourth family had abnormal zygote cleavage. All displayed only the infertility phenotype without Wilms tumors or any other abnormalities. In vitro and in vivo studies showed that the identified variants reduced the protein abundance of TRIP13 and caused its downstream molecule, HORMAD2, to accumulate in HeLa cells and in proband-derived lymphoblastoid cells. The chromosome mis-segregation assay showed that variants did not have any effects on mitosis. Injecting TRIP13 cRNA into oocytes from one affected individual was able to rescue the phenotype, which has implications for future therapeutic treatments. This study reports pathogenic variants in TRIP13 responsible for oocyte meiotic arrest, and it highlights the pivotal but different roles of TRIP13 in meiosis and mitosis. These findings also indicate that different dosage effects of mutant TRIP13 might result in two distinct human diseases.


Assuntos
ATPases Associadas a Diversas Atividades Celulares/genética , Proteínas de Ciclo Celular/genética , Infertilidade Feminina/genética , Mutação de Sentido Incorreto/genética , Oócitos/patologia , Adulto , Alelos , Linhagem Celular Tumoral , Feminino , Células HeLa , Homozigoto , Humanos , Meiose/genética , Fenótipo , Zigoto/patologia
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