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Abstract
Improving human healthspan in our rapidly aging population has never been more imperative. Telomeres, protective "caps" at the ends of linear chromosomes, are essential for maintaining genome stability of eukaryotic genomes. Due to their physical location and the "end-replication problem" first envisioned by Dr. Alexey Olovnikov, telomeres shorten with cell division, the implications of which are remarkably profound. Telomeres are hallmarks and molecular drivers of aging, as well as fundamental integrating components of the cumulative effects of genetic, lifestyle, and environmental factors that erode telomere length over time. Ongoing telomere attrition and the resulting limit to replicative potential imposed by cellular senescence serves a powerful tumor suppressor function, and also underlies aging and a spectrum of age-related degenerative pathologies, including reduced fertility, dementias, cardiovascular disease and cancer. However, very little data exists regarding the extraordinary stressors and exposures associated with long-duration space exploration and eventual habitation of other planets, nor how such missions will influence telomeres, reproduction, health, disease risk, and aging. Here, we briefly review our current understanding, which has advanced significantly in recent years as a result of the NASA Twins Study, the most comprehensive evaluation of human health effects associated with spaceflight ever conducted. Thus, the Twins Study is at the forefront of personalized space medicine approaches for astronauts and sets the stage for subsequent missions. We also extrapolate from current understanding to future missions, highlighting potential biological and biochemical strategies that may enable human survival, and consider the prospect of longevity in the extreme environment of space.
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Affiliation(s)
- Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine and WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, USA
| | - Maria A Sierra
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine and WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY, USA
- Tri-Institutional Computational Biology & Medicine Program, Weill Cornell Medicine, New York, NY, USA
| | - Henry J Feng
- Department of Biological Sciences, Columbia University, New York, NY, USA
- Faculty of Medicine and Health, Sydney Medical School, University of Sydney, Sydney, Australia
| | - Susan M Bailey
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA.
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Liu PM, Feng B, Shi JF, Feng HJ, Hu ZJ, Chen YH, Zhang JP. A deep-learning model using enhanced chest CT images to predict PD-L1 expression in non-small-cell lung cancer patients. Clin Radiol 2023; 78:e689-e697. [PMID: 37460338 DOI: 10.1016/j.crad.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/11/2023] [Accepted: 05/18/2023] [Indexed: 09/03/2023]
Abstract
AIM To develop a deep-learning model using contrast-enhanced chest computed tomography (CT) images to predict programmed death-ligand 1 (PD-L1) expression in patients with non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS Preoperative enhanced chest CT images and immunohistochemistry results for PD-L1 expression (<1% and ≥1% were defined as negative and positive, respectively) were collected retrospectively from 125 NSCLC patients to train and validate a deep-learning radiomics model (DLRM) for the prediction of PD-L1 expression in tumours. The DLRM was developed by combining the deep-learning signature (DLS) obtained from a convolutional neural network and clinicopathological factors. The indexes of the area under the curve (AUC), integrated discrimination improvement (IDI), and decision curve analysis (DCA) were used to evaluate the efficiency of the DLRM. RESULTS DLS and tumour stage were identified as independent predictors of PD-L1 expression by the DLRM. The AUCs of the DLRM were 0.804 (95% confidence interval: 0.697-0.911) and 0.804 (95% confidence interval: 0.679-0.929) in the training and validation cohorts, respectively. IDI analysis showed the DLRM had better diagnostic accuracy than DLS (0.0028 [p<0.05]) in the validation cohort. Additionally, DCA revealed that the DLRM had more net benefit than the DLS for clinical utility. CONCLUSION The proposed DLRM using enhanced chest CT images could function as a non-invasive diagnostic tool to differentiate PD-L1 expression in NSCLC patients.
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Affiliation(s)
- P M Liu
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - B Feng
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - J F Shi
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - H J Feng
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Z J Hu
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - Y H Chen
- School of Electronic Information and Automation, Guilin University of Aerospace Technology, Guilin, Guangxi, 541004, China
| | - J P Zhang
- Cancer Center, Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan, 030032, China; Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
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Feng HJ, Ouyang W, Liu JH, Sun YG, Hu R, Huang LH, Xian JL, Jing CF, Zhou MJ. Global microRNA profiles and signaling pathways in the development of cardiac hypertrophy. ACTA ACUST UNITED AC 2014; 47:361-8. [PMID: 24728214 PMCID: PMC4075303 DOI: 10.1590/1414-431x20142937] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 01/21/2014] [Indexed: 11/22/2022]
Abstract
Hypertrophy is a major predictor of progressive heart disease and has an adverse
prognosis. MicroRNAs (miRNAs) that accumulate during the course of cardiac
hypertrophy may participate in the process. However, the nature of any interaction
between a hypertrophy-specific signaling pathway and aberrant expression of miRNAs
remains unclear. In this study, Spague Dawley male rats were treated with transverse
aortic constriction (TAC) surgery to mimic pathological hypertrophy. Hearts were
isolated from TAC and sham operated rats (n=5 for each group at 5, 10, 15, and 20
days after surgery) for miRNA microarray assay. The miRNAs dysexpressed during
hypertrophy were further analyzed using a combination of bioinformatics algorithms in
order to predict possible targets. Increased expression of the target genes
identified in diverse signaling pathways was also analyzed. Two sets of miRNAs were
identified, showing different expression patterns during hypertrophy. Bioinformatics
analysis suggested the miRNAs may regulate multiple hypertrophy-specific signaling
pathways by targeting the member genes and the interaction of miRNA and mRNA might
form a network that leads to cardiac hypertrophy. In addition, the multifold changes
in several miRNAs suggested that upregulation of rno-miR-331*, rno-miR-3596b,
rno-miR-3557-5p and downregulation of rno-miR-10a, miR-221, miR-190, miR-451 could be
seen as biomarkers of prognosis in clinical therapy of heart failure. This study
described, for the first time, a potential mechanism of cardiac hypertrophy involving
multiple signaling pathways that control up- and downregulation of miRNAs. It
represents a first step in the systematic discovery of miRNA function in
cardiovascular hypertrophy.
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Affiliation(s)
- H J Feng
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - W Ouyang
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - J H Liu
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - Y G Sun
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - R Hu
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - L H Huang
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - J L Xian
- Zhujiang Hospital, Department of Nuclear Medicine, Southern Medical University, Guangzhou, China
| | - C F Jing
- National Engineering Research Center, South China Sea Marine Biotechnology, Sun Yat-Sen University, Guangzhou, China
| | - M J Zhou
- National Engineering Research Center, South China Sea Marine Biotechnology, Sun Yat-Sen University, Guangzhou, China
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Raisinghani M, Feng HJ, Faingold CL. Glutamatergic activation of the amygdala differentially mimics the effects of audiogenic seizure kindling in two substrains of genetically epilepsy-prone rats. Exp Neurol 2003; 183:516-22. [PMID: 14552892 DOI: 10.1016/s0014-4886(03)00177-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Comparisons of neuronal network mechanisms in closely related inherited seizure models are providing novel insights into epileptogenic pathophysiology. Genetically epilepsy-prone rats (GEPRs) exist in two substrains that inherit long-term susceptibility to behaviorally distinct audiogenic seizures (AGS). GEPR-3s exhibit generalized clonic AGS, while GEPR-9s exhibit generalized tonic AGS. After AGS kindling the tonic AGS of GEPR-9s is followed by generalized posttonic clonus (PTC), while the generalized clonic AGS is followed by facial and forelimb (F&F) clonus in GEPR-3s. PTC and F&F clonus are very rare in GEPRs before AGS kindling. The neuronal network subserving AGS in GEPR-9s lies exclusively in brainstem sites, but amygdala (AMG) and other sites are recruited into the network after AGS kindling. The present study attempted to mimic the effects of AGS kindling by bilaterally microinjecting subconvulsive doses of N-methyl-D-aspartate (NMDA) into the AMG of nonkindled GEPRs. NMDA (10 nmol/side) microinjected into AMG reversibly induced susceptibility to F&F clonus immediately following generalized clonic AGS in most nonkindled GEPR-3s. NMDA (7.5 nmol/side), microinjected into AMG temporarily induced susceptibility to generalized PTC immediately following tonic AGS in most nonkindled GEPR-9s. No seizures were induced in normal rats by these treatments, and no seizures were seen in GEPRs with these NMDA doses except those induced by acoustic stimuli. These findings support a critical role in AGS kindling for the AMG in the neuronal networks for both forms of AGS. However, the behavioral effect of the treatment was different in the two AGS substrains, suggesting interrelated but not identical pathophysiological mechanisms in these closely related epilepsy models.
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Affiliation(s)
- M Raisinghani
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, IL 62794-9629, USA
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Feng HJ, Naritoku DK, Randall ME, Faingold CL. Modulation of audiogenically kindled seizures by gamma-aminobutyric acid-related mechanisms in the amygdala. Exp Neurol 2001; 172:477-81. [PMID: 11716572 DOI: 10.1006/exnr.2001.7810] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Repetitive induction of audiogenic seizures (AGSs) ("AGS kindling") results in expansion of the AGS neuronal network from the brainstem to forebrain structures. AGSs in kindled genetically epilepsy-prone rats (GEPR-9s) exhibit a significant increase in the duration of posttonic clonus (PTC). The amygdala (AMG) does not appear to be a required network component before AGS kindling, but this structure is implicated in the seizure network after AGS kindling. gamma-Aminobutyric acid (GABA) is a major neurotransmitter in AMG, and histamine receptor activation is also reported to stimulate GABA release. The present study examined the effect on audiogenically kindled seizures of focal microinjections into the AMG of GEPR-9s. AGS kindling involved induction of 14 AGSs in GEPR-9s. Bilateral microinjection of a GABA(A) agonist, muscimol (0.3 nmol/side), into the AMG significantly reduced the duration of PTC, starting 0.5 h after drug infusion, with recovery by 24 h. Microinjection of histamine (60 nmol/side) suppressed PTC at 0.5 h, with total blockade at 24 h, but the seizure pattern did not revert to that observed before kindling until 120 h. This long duration suggests that mechanisms in addition to modulation of GABA function may be involved in the effect of histamine. The wild running and tonic components of AGS were never affected by microinjection of these agents into the AMG. These findings confirm previous work suggesting that the AMG is not a required nucleus in the AGS neuronal network before kindling. However, the AMG becomes critical in expansion of the seizure network during AGS kindling, and audiogenically kindled seizures are negatively modulated by increased GABA function.
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Affiliation(s)
- H J Feng
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, Illinois 62794, USA
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Abstract
Susceptibility to behaviorally similar audiogenic seizures (AGS) occurs genetically and is inducible during ethanol withdrawal (ETX). Comparisons between AGS mechanisms of genetically epilepsy-prone rats (GEPR-9s) and ethanol-withdrawn rats (ETX-Rs) are yielding information about general pathophysiological mechanisms of epileptogenesis. The inferior colliculus (IC) is the AGS initiation site. Excitatory amino acid (EAA) abnormalities in the IC are implicated in AGS, and histamine and adenosine receptor activation each reduce EAA release and inhibit several seizure types. Previous studies indicate that focal infusion of an adenosine receptor agonist into the IC blocked AGS in GEPR-9s, but the effects of adenosine receptor activation in the IC on AGS in ETX-Rs are unknown. The effects of histamine receptor activation on either form of AGS are also unexamined. The present study evaluated effects of histamine or a nonselective adenosine A(1) agonist, 2-chloroadenosine, on AGS by focal microinjection into the IC. Ethanol dependence and AGS susceptibility were induced in normal rats by intragastric ethanol. Histamine (40 or 60 nmol/side) significantly reduced AGS in GEPR-9s, but histamine in doses up to 120 nmol/side did not affect AGS in ETX-Rs. 2-Chloroadenosine (5 or 10 nmol/side) did not affect AGS in ETX-Rs, despite the effectiveness of lower doses of this agent in GEPR-9s reported previously. Thus, histamine and adenosine receptors in the IC modulate AGS of GEPR-9s, but do not modulate ETX-induced AGS. The reasons for this difference may involve the chronicity of AGS susceptibility in GEPR-9s, which may lead to more extensive neuromodulation as compensatory mechanisms to limit the seizures compared to the acute AGS of ETX-Rs.
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Affiliation(s)
- H J Feng
- Department of Pharmacology, Southern Illinois University School of Medicine, Springfield, Illinois 62794-9629, USA
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Feng HJ, Huang SL, Wang W, Zhou HH. The induction effect of rifampicin on activity of mephenytoin 4'-hydroxylase related to M1 mutation of CYP2C19 and gene dose. Br J Clin Pharmacol 1998; 45:27-9. [PMID: 9489590 PMCID: PMC1873992 DOI: 10.1046/j.1365-2125.1998.00643.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIMS To determine the induction effect of rifampicin on the activity of 4'-hydroxylase in poor metabolizers (PMs) with m1 mutation of S-mephenytoin 4'-hydroxylation and the relationship of the effect with gene dose. METHODS Seven extensive metabolizers (EMs) of S-mephenytoin 4'-hydroxylation and five PMs with m1 mutation were chosen to take rifampicin 300 mg day(-1) orally for 22 days. Prior to and after rifampicin treatment, each subject was given racemic mephenytoin 100 mg. The 4'-hydroxymephenytoin (4'-OH-MP) excreted in the 0-24 h urine and mephenytoin S/R ratio in the 0-8 h urine were determined by h.p.l.c. and GC, respectively. RESULTS In all EMs, the excretion of 4'-OH-MP in the 0-24 h urine was increased by 146.4 +/- 17.9%, 0-8 h urinary mephenytoin S/R ratio was decreased by 77.3 +/- 8.8%, the percentage increase in the 0-24 h excretion of 4'-OH-MP in those CYP2C19 homozygous (wt/wt) was greater than that in those heterozygous (wt/m1 and wt/m2) (203.9 +/- 42.5% vs 69.6 +/- 4.1%). 0-8 h urinary mephenytoin S/R ratio of those PMs with m1 mutation was decreased by 9.6%, the amount of 4'-OH-MP excreted in the 0-24 h urine was increased by 80.1 +/- 48.0%. CONCLUSIONS The activity of 4'-hydroxylase of PMs with m1 mutation of S-mephenytoin 4'-hydroxylation can be induced by rifampicin and the inducing effect of rifampicin on 4'-hydroxylase is gene dependent.
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Affiliation(s)
- H J Feng
- Pharmacogenetics Research Institute, Hunan Medical University, Changsha, PR China
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