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1.
Curr Oncol ; 31(2): 693-703, 2024 01 25.
Article in English | MEDLINE | ID: mdl-38392045

ABSTRACT

As childhood cancer treatments have improved to include new and innovative agents, the need for more advanced monitoring of their long-term effects and related research has increased. This has resulted in a need for evidence-based research methodologies for the longitudinal care of childhood cancer patients treated with targeted agents and immunotherapies. The rationale for this pilot study was to determine the feasibility and acceptability of a data capture methodology for pediatric, adolescent, and young adult cancer patients treated with targeted agents and immunotherapy as there is little research to inform this delivery of care. Data were collected from thirty-two patients and two providers for descriptive statistics and thematic analyses. Feasibility was characterized by expected participant attrition. Key drivers of acceptability were (1) providers' language and clarity of communication and (2) convenient participation requirements. Long-term follow-up research practices developed with input from key stakeholders, including patients, caregivers, and providers, can lead to acceptable and feasible research protocols that optimize successful participant recruitment. These evidence-based research practices can result in high participant satisfaction and can be implemented as program development initiatives across centers caring for childhood cancer survivors.


Subject(s)
Delivery of Health Care , Neoplasms , Adolescent , Young Adult , Humans , Child , Feasibility Studies , Pilot Projects , Neoplasms/drug therapy , Immunotherapy
2.
PLoS One ; 18(12): e0293907, 2023.
Article in English | MEDLINE | ID: mdl-38060522

ABSTRACT

Obesity is a common finding and a major pathogenetic factor in obstructive sleep apnea (OSA) in adults. To understand the mechanisms behind this, the present study investigated the tissue properties and respiratory kinematics of the tongue base and soft palate in the obese OSA minipig model. In 4 verified obese/OSA and 3 non-obese/non-OSA control minipigs, MRI fat-weighted images, ultrasound elastography (USE), and sleep video-fluoroscopy (SVF) were performed to quantify the fat composition, tissue stiffness, and respiratory kinematics of the tongue base and soft palate during sedated sleep. The results indicated that the fat composition gradually increased from the rostral to caudal tongue base, particularly in the posterior 1/3 of the tongue base, regardless of the presence of obesity and OSA. However, this trend was not seen in the soft palate and pharyngeal wall. The pharyngeal wall presented the highest fat composition as compared with the tongue base and soft palate. Overall, obese OSA minipigs showed stiffer tongue tissue than the controls, particularly in the rostral region of the tongue in obese Yucatan minipigs. The respiratory moving ranges of the soft palate were greater in both dorsal-ventral and rostral-caudal directions and during both respiratory and expiratory phases in OSA obese than control minipigs, and the largest moving ranges were seen in OSA obese Panepinto minipigs. The moving range of the tongue base was significantly smaller. These results suggest more fat infiltration in the caudal region of the tongue base regardless of the presence of obesity and/or OSA. The greater tissue stiffness of the tongue in obese OSA minipigs may result from altered neuromuscular drive.


Subject(s)
Sleep Apnea, Obstructive , Adult , Animals , Humans , Swine , Biomechanical Phenomena , Swine, Miniature , Palate, Soft/pathology , Tongue/pathology , Obesity
3.
Nat Commun ; 13(1): 4221, 2022 07 21.
Article in English | MEDLINE | ID: mdl-35864091

ABSTRACT

Sonic hedgehog (Shh) is essential for limb development, and the mechanisms that govern the propagation and maintenance of its expression has been well studied; however, the mechanisms that govern the initiation of Shh expression are incomplete. Here we report that ETV2 initiates Shh expression by changing the chromatin status of the developmental limb enhancer, ZRS. Etv2 expression precedes Shh in limb buds, and Etv2 inactivation prevents the opening of limb chromatin, including the ZRS, resulting in an absence of Shh expression. Etv2 overexpression in limb buds causes nucleosomal displacement at the ZRS, ectopic Shh expression, and polydactyly. Areas of nucleosome displacement coincide with ETS binding site clusters. ETV2 also functions as a transcriptional activator of ZRS and is antagonized by ETV4/5 repressors. Known human polydactyl mutations introduce novel ETV2 binding sites in the ZRS, suggesting that ETV2 dosage regulates ZRS activation. These studies identify ETV2 as a pioneer transcription factor (TF) regulating the onset of Shh expression, having both a chromatin regulatory role and a transcriptional activation role.


Subject(s)
Hedgehog Proteins , Limb Buds , Polydactyly , Transcription Factors , Animals , Chromatin/genetics , Enhancer Elements, Genetic , Gene Expression Regulation, Developmental , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Humans , Limb Buds/growth & development , Mice , Transcription Factors/genetics , Transcription Factors/metabolism
4.
Neurol Int ; 13(2): 166-174, 2021 Apr 15.
Article in English | MEDLINE | ID: mdl-33920752

ABSTRACT

BACKGROUND AND AIMS: Nerve conduction study (NCS) measures how fast an electrical impulse moves through the nerve and is a standard technique for diagnosing and assessing neurological diseases. Despite diabetes and obesity being a common accompaniment of peripheral neuropathy, their effects on NCS patterns have not been elucidated conclusively. Our study aimed to assess several anthropometric and metabolic factors with NCS outcomes to address this gap. RESEARCH DESIGN AND METHODS: This retrospective chart analysis study was conducted on subjects who underwent NCS between 1 January 2009 and 31 December 2019 at a regional hospital. Metabolic, anthropometric, demographical and NCS data were collected from patients' health records. RESULTS: In total, 120 subjects presenting with sensorimotor peripheral neuropathy symptoms were included in the study. Age, HbA1c, urea and ESR variables were significantly negatively associated with nerve conduction outcomes (Spearman's correlation rho between -0.210 and -0.456, p < 0.038). HbA1c and age consistently had the most substantial contribution to velocity and amplitude in all regression models (beta coefficients between -0.157 and 0.516, p < 0.001). Urea also significantly account for a large amount of variance in amplitude and velocity in the lower limbs. CONCLUSION: This study suggests that the severity of sensorimotor neuropathy is influenced by glycaemic control, age and uraemia. The interpretation of NCS results must consider these factors suggesting that improved glycaemic and uraemic control may improve nerve conduction outcomes.

5.
Cancer Res ; 77(13): 3391-3405, 2017 07 01.
Article in English | MEDLINE | ID: mdl-28522753

ABSTRACT

Autophagy activated after DNA damage or other stresses mitigates cellular damage by removing damaged proteins, lipids, and organelles. Activation of the master metabolic kinase AMPK enhances autophagy. Here we report that cyclin D1 restrains autophagy by modulating the activation of AMPK. In cell models of human breast cancer or in a cyclin D1-deficient model, we observed a cyclin D1-mediated reduction in AMPK activation. Mechanistic investigations showed that cyclin D1 inhibited mitochondrial function, promoted glycolysis, and reduced activation of AMPK (pT172), possibly through a mechanism that involves cyclin D1-Cdk4/Cdk6 phosphorylation of LKB1. Our findings suggest how AMPK activation by cyclin D1 may couple cell proliferation to energy homeostasis. Cancer Res; 77(13); 3391-405. ©2017 AACR.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Breast Neoplasms/genetics , Cyclin D1/metabolism , Protein Serine-Threonine Kinases/metabolism , 3T3 Cells , AMP-Activated Protein Kinase Kinases , Animals , Autophagy/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Cell Proliferation/genetics , Female , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Signal Transduction , Transfection
6.
Proc Natl Acad Sci U S A ; 111(39): 14235-40, 2014 Sep 30.
Article in English | MEDLINE | ID: mdl-25225400

ABSTRACT

The quorum sensing signal autoinducer-2 (AI-2) regulates important bacterial behaviors, including biofilm formation and the production of virulence factors. Some bacteria, such as Escherichia coli, can quench the AI-2 signal produced by a variety of species present in the environment, and thus can influence AI-2-dependent bacterial behaviors. This process involves uptake of AI-2 via the Lsr transporter, followed by phosphorylation and consequent intracellular sequestration. Here we determine the metabolic fate of intracellular AI-2 by characterizing LsrF, the terminal protein in the Lsr AI-2 processing pathway. We identify the substrates of LsrF as 3-hydroxy-2,4-pentadione-5-phosphate (P-HPD, an isomer of AI-2-phosphate) and coenzyme A, determine the crystal structure of an LsrF catalytic mutant bound to P-HPD, and identify the reaction products. We show that LsrF catalyzes the transfer of an acetyl group from P-HPD to coenzyme A yielding dihydroxyacetone phosphate and acetyl-CoA, two key central metabolites. We further propose that LsrF, despite strong structural homology to aldolases, acts as a thiolase, an activity previously undescribed for this family of enzymes. With this work, we have fully characterized the biological pathway for AI-2 processing in E. coli, a pathway that can be used to quench AI-2 and control quorum-sensing-regulated bacterial behaviors.


Subject(s)
Carrier Proteins/metabolism , Escherichia coli Proteins/metabolism , Homoserine/analogs & derivatives , Lactones/metabolism , Acetyltransferases/chemistry , Acetyltransferases/genetics , Acetyltransferases/metabolism , Amino Acid Substitution , Carrier Proteins/chemistry , Carrier Proteins/genetics , Coenzyme A/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/genetics , Homoserine/metabolism , Kinetics , Models, Molecular , Mutagenesis, Site-Directed , Protein Conformation , Protein Processing, Post-Translational , Quorum Sensing
7.
Dev Biol ; 383(2): 285-94, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24051227

ABSTRACT

Atypical cadherins Dachsous (Ds) and Fat coordinate the establishment of planar polarity, essential for the patterning of complex tissues and organs. The precise mechanisms by which this system acts, particularly in cases where Ds and Fat act independently of the 'core' frizzled system, are still the subject of investigation. Examining the deployment of the Ds-Fat system in different tissues of the model organism Drosophila, has provided insights into the general mechanisms by which polarity is established and propagated to coordinate outcomes across a field of cells. The Drosophila embryonic epidermis provides a simple model epithelia where the establishment of polarity can be observed from start to finish, and in the absence of proliferation, over a fixed number of cells. Using the asymmetric placement of f-actin during denticle assembly as a read-out of polarity, we examine the requirement for Ds and Fat in establishing polarity across the denticle field. Comparing detailed phenotypic analysis with steady state protein enrichment revealed a spatially restricted requirement for the Ds-Fat system within the posterior denticle field. Ectopic Ds signaling provides evidence for a model whereby Ds acts to asymmetrically enrich Fat in a neighboring cell, in turn polarizing the cell to specify the position of the actin-based protrusions at the cell cortex.


Subject(s)
Cadherins/metabolism , Cell Adhesion Molecules/metabolism , Cell Polarity , Cell Surface Extensions/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/embryology , Embryo, Nonmammalian/metabolism , Epithelium/embryology , Actins/metabolism , Animals , Body Patterning , Drosophila melanogaster/anatomy & histology , Drosophila melanogaster/cytology , Drosophila melanogaster/metabolism , Embryo, Nonmammalian/anatomy & histology , Embryo, Nonmammalian/cytology , Epithelium/metabolism , Mutation/genetics , Phenotype , Signal Transduction
8.
IEEE Trans Neural Netw ; 21(11): 1780-92, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20858578

ABSTRACT

Despite the popularity and success of neural networks in research, the number of resulting commercial or industrial applications has been limited. A primary cause for this lack of adoption is that neural networks are usually implemented as software running on general-purpose processors. Hence, a hardware implementation that can exploit the inherent parallelism in neural networks is desired. This paper investigates how the restricted Boltzmann machine (RBM), which is a popular type of neural network, can be mapped to a high-performance hardware architecture on field-programmable gate array (FPGA) platforms. The proposed modular framework is designed to reduce the time complexity of the computations through heavily customized hardware engines. A method to partition large RBMs into smaller congruent components is also presented, allowing the distribution of one RBM across multiple FPGA resources. The framework is tested on a platform of four Xilinx Virtex II-Pro XC2VP70 FPGAs running at 100 MHz through a variety of different configurations. The maximum performance was obtained by instantiating an RBM of 256 × 256 nodes distributed across four FPGAs, which resulted in a computational speed of 3.13 billion connection-updates-per-second and a speedup of 145-fold over an optimized C program running on a 2.8-GHz Intel processor.


Subject(s)
Artificial Intelligence , Computer Simulation/standards , Neural Networks, Computer , Computers/standards , Computers/trends , Programming Languages , Software Validation
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