ABSTRACT
The coactivator p300/CREB-binding protein (CBP) regulates genes by facilitating the assembly of transcriptional machinery and by acetylating histones and other factors. However, it remains mostly unclear how both functions of p300 are dynamically coordinated during gene control. Here, we showed that p300 can orchestrate two functions through the formation of dynamic clusters with certain transcription factors (TFs), which is mediated by the interactions between a TF's transactivation domain (TAD) and the intrinsically disordered regions of p300. Co-condensation can enable spatially defined, all-or-none activation of p300's catalytic activity, priming the recruitment of coactivators, including Brd4. We showed that co-condensation can modulate transcriptional initiation rate and burst duration of target genes, underlying nonlinear gene regulatory functions. Such modulation is consistent with how p300 might shape gene bursting kinetics globally. Altogether, these results suggest an intriguing gene regulation mechanism, in which TF and p300 co-condensation contributes to transcriptional bursting regulation and cooperative gene control.
Subject(s)
E1A-Associated p300 Protein/metabolism , Transcription Factors/metabolism , Transcription, Genetic/genetics , Transcriptional Activation/genetics , Acetylation , Animals , CHO Cells , CREB-Binding Protein/metabolism , Cell Line , Cricetulus , Gene Expression Regulation/genetics , HEK293 Cells , Histones/metabolism , Humans , Kinetics , Mice , Trans-Activators/metabolismABSTRACT
In this article, we develop CausalEGM, a deep learning framework for nonlinear dimension reduction and generative modeling of the dependency among covariate features affecting treatment and response. CausalEGM can be used for estimating causal effects in both binary and continuous treatment settings. By learning a bidirectional transformation between the high-dimensional covariate space and a low-dimensional latent space and then modeling the dependencies of different subsets of the latent variables on the treatment and response, CausalEGM can extract the latent covariate features that affect both treatment and response. By conditioning on these features, one can mitigate the confounding effect of the high dimensional covariate on the estimation of the causal relation between treatment and response. In a series of experiments, the proposed method is shown to achieve superior performance over existing methods in both binary and continuous treatment settings. The improvement is substantial when the sample size is large and the covariate is of high dimension. Finally, we established excess risk bounds and consistency results for our method, and discuss how our approach is related to and improves upon other dimension reduction approaches in causal inference.
ABSTRACT
To cause infection, pathogens must overcome bottlenecks imposed by the host immune system. These bottlenecks restrict the inoculum and largely determine whether pathogen exposure results in disease. Infection bottlenecks therefore quantify the effectiveness of immune barriers. Here, using a model of Escherichia coli systemic infection, we identify bottlenecks that tighten or widen with higher inoculum sizes, revealing that the efficacy of innate immune responses can increase or decrease with pathogen dose. We term this concept "dose scaling". During E. coli systemic infection, dose scaling is tissue specific, dependent on the lipopolysaccharide (LPS) receptor TLR4, and can be recapitulated by mimicking high doses with killed bacteria. Scaling therefore depends on sensing of pathogen molecules rather than interactions between the host and live bacteria. We propose that dose scaling quantitatively links innate immunity with infection bottlenecks and is a valuable framework for understanding how the inoculum size governs the outcome of pathogen exposure.
Subject(s)
Escherichia coli Infections , Escherichia coli , Humans , Immunity, InnateABSTRACT
Extracellular vesicles (EVs) released from healthy endothelial cells (ECs) have shown potential for promoting angiogenesis, but their therapeutic efficacy remains poorly understood. We have previously shown that transplantation of a human embryonic stem cell-derived endothelial cell product (hESC-ECP), promotes new vessel formation in acute ischemic disease in mice, likely via paracrine mechanism(s). Here, we demonstrated that EVs from hESC-ECPs (hESC-eEVs) significantly increased EC tube formation and wound closure in vitro at ultralow doses, whereas higher doses were ineffective. More important, EVs isolated from the mesodermal stage of the differentiation (hESC-mEVs) had no effect. Small RNA sequencing revealed that hESC-eEVs have a unique transcriptomic profile and are enriched in known proangiogenic microRNAs (miRNAs, miRs). Moreover, an in silico analysis identified three novel hESC-eEV-miRNAs with potential proangiogenic function. Differential expression analysis suggested that two of those, miR-4496 and miR-4691-5p, are highly enriched in hESC-eEVs. Overexpression of miR-4496 or miR-4691-5p resulted in increased EC tube formation and wound closure in vitro, validating the novel proangiogenic function of these miRNAs. In summary, we demonstrated that hESC-eEVs are potent inducers of EC angiogenic response at ultralow doses and contain a unique EV-associated miRNA repertoire, including miR-4496 and miR-4691-5p, with novel proangiogenic function.
Subject(s)
Extracellular Vesicles , MicroRNAs , Humans , Animals , Mice , MicroRNAs/genetics , MicroRNAs/metabolism , Endothelial Cells/metabolism , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , Cell Differentiation/genetics , Stem Cells/metabolismABSTRACT
RATIONALE: Optimizing pyrazinamide dosing is critical to improve treatment efficacy while minimizing toxicity during tuberculosis treatment. Study 31/ACTG A5349 represents the largest Phase 3 randomized controlled therapeutic trial to date for such investigation. OBJECTIVES: We sought to report pyrazinamide pharmacokinetic parameters, risk factors for lower pyrazinamide exposure, and relationships between pyrazinamide exposure with efficacy and safety outcomes. We aimed to determine pyrazinamide dosing strategies that optimize risks and benefits. METHODS: We analyzed pyrazinamide steady-state pharmacokinetic data using population nonlinear mixed-effects models. We evaluated the contribution of pyrazinamide exposure to long-term efficacy using parametric time-to-event models and safety outcomes using logistic regression. We evaluated optimal dosing with therapeutic windows targeting ≥95% durable cure and safety within the observed proportion of the primary safety outcome. MEASUREMENTS AND MAIN RESULTS: Among 2255 participants with 6978 plasma samples, pyrazinamide displayed 7-fold exposure variability (151-1053 mg·h/L). Body weight was not a clinically relevant predictor of drug clearance and thus did not justify the need for weight-banded dosing. Both clinical and safety outcomes were associated with pyrazinamide exposure, resulting in a therapeutic window of 231-355 mg·h/L for the control and 226-349 mg·h/L for the rifapentine-moxifloxacin regimen. Flat dosing of pyrazinamide at 1000 mg would have permitted an additional 13.1% (n=96) participants allocated to the control and 9.2% (n=70) to the rifapentine-moxifloxacin regimen dosed within the therapeutic window, compared to the current weight-banded dosing. CONCLUSIONS: Flat dosing of pyrazinamide at 1000 mg daily would be readily implementable and could optimize treatment outcomes in drug-susceptible tuberculosis. Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT02410772. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).
ABSTRACT
BACKGROUND: The potential benefits of drug combination synergy in cancer medicine are significant, yet the risks must be carefully managed due to the possibility of increased toxicity. Although artificial intelligence applications have demonstrated notable success in predicting drug combination synergy, several key challenges persist: (1) Existing models often predict average synergy values across a restricted range of testing dosages, neglecting crucial dose amounts and the mechanisms of action of the drugs involved. (2) Many graph-based models rely on static protein-protein interactions, failing to adapt to dynamic and higher-order relationships. These limitations constrain the applicability of current methods. RESULTS: We introduce SAFER, a Sub-hypergraph Attention-based graph model, addressing these issues by incorporating complex relationships among biological knowledge networks and considering dosing effects on subject-specific networks. SAFER outperformed previous models on the benchmark and the independent test set. The analysis of subgraph attention weight for the lung cancer cell line highlighted JAK-STAT signaling pathway, PRDM12, ZNF781, and CDC5L that have been implicated in lung fibrosis. CONCLUSIONS: SAFER presents an interpretable framework designed to identify drug-responsive signals. Tailored for comprehending dose effects on subject-specific molecular contexts, our model uniquely captures dose-level drug combination responses. This capability unlocks previously inaccessible avenues of investigation compared to earlier models. Furthermore, the SAFER framework can be leveraged by future inquiries to investigate molecular networks that uniquely characterize individual patients and can be applied to prioritize personalized effective treatment based on safe dose combinations.
Subject(s)
Neural Networks, Computer , Humans , Cell Line, Tumor , Drug Synergism , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Dose-Response Relationship, Drug , Signal Transduction/drug effects , Antineoplastic Agents/pharmacologyABSTRACT
BACKGROUND: In the AMPLITUDE-O (Effect of Efpeglenatide on Cardiovascular Outcomes) cardiovascular outcomes trial, adding either 4 mg or 6 mg weekly of the glucagon-like peptide-1 receptor agonist efpeglenatide to usual care reduced major adverse cardiovascular events (MACE) in people with type 2 diabetes at high cardiovascular risk. Whether these benefits are dose related remains uncertain. METHODS: Participants were randomly assigned in a 1:1:1 ratio to placebo, 4 mg or 6 mg of efpeglenatide. The effect of 6 mg versus placebo and of 4 mg versus placebo on MACE (a nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular or unknown causes) and on all the secondary composite cardiovascular and kidney outcomes was assessed. A dose-response relationship was assessed using the log-rank test and χ2 statistic for trend. RESULTS: During a median follow-up of 1.8 years, MACE occurred in 125 (9.2%) participants assigned to placebo, 84 (6.2%) participants assigned to 6 mg of efpeglenatide (hazard ratio [HR], 0.65 [95% CI, 0.5-0.86]; P=0.0027), and 105 (7.7%) assigned to 4 mg of efpeglenatide (HR, 0.82 [95% CI, 0.63-1.06]; P=0.14). Participants receiving high-dose efpeglenatide also experienced fewer secondary outcomes, including the composite of MACE, coronary revascularization, or hospitalization for unstable angina (HR, 0.73 for 6 mg, P=0.011; HR, 0.85 for 4 mg, P=0.17), a kidney composite outcome comprising sustained new macroalbuminuria, a ≥40% decline in estimated glomerular filtration rate or renal failure (HR, 0.63 for 6 mg, P<0.0001; HR, 0.73 for 4 mg, P=0.0009), MACE or any death (HR, 0.67 for 6 mg, P=0.0021; HR, 0.81 for 4 mg, P=0.08), a kidney function outcome comprising a sustained ≥40% decline in estimated glomerular filtration rate, renal failure, or death (HR, 0.61 for 6 mg, P=0.0072; HR, 0.97 for 4 mg, P=0.83), and the composite of MACE, any death, heart failure hospitalization, or the kidney function outcome (HR, 0.63 for 6 mg, P=0.0002; HR, 0.81 for 4 mg, P=0.067). A clear dose-response was noted for all primary and secondary outcomes (all P for trend ≤0.018). CONCLUSIONS: The graded salutary relationship between efpeglenatide dose and cardiovascular outcomes suggests that titrating efpeglenatide and potentially other glucagon-like peptide-1 receptor agonists to high doses may maximize their cardiovascular and renal benefits. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03496298.
Subject(s)
Cardiovascular Diseases , Cardiovascular System , Diabetes Mellitus, Type 2 , Renal Insufficiency , Humans , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/drug therapy , Glucagon-Like Peptide-1 Receptor , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Treatment Outcome , Hypoglycemic Agents/adverse effectsABSTRACT
The current study estimated effects of intervention dose (attendance) of a cognitive behavioral prevention (CBP) program on depression-free days (DFD) in adolescent offspring of parents with a history of depression. As part of secondary analyses of a multi-site randomized controlled trial, we analyzed the complete intention-to-treat sample of 316 at-risk adolescents ages 13-17. Youth were randomly assigned to the CBP program plus usual care (n=159) or to usual care alone (n=157). The CBP program involved 8 weekly acute sessions and 6 monthly continuation sessions. Results showed that higher CBP program dose predicted more DFDs, with a key threshold of approximately 75% of a full dose in analyses employing instrumental variable methodology to control multiple channels of bias. Specifically, attending at more than 75% of acute phase sessions led to 45.3 more DFDs over the 9-month period post randomization, which accounted for over 12% of the total follow-up days. Instrument sets were informed by study variables and external data including weather and travel burden. In contrast, conventional analysis methods failed to find a significant dose-outcome relation. Application of the instrumental variable approach, which better controls the influence of confounding, demonstrated that higher CBP program dose resulted in more DFDs.
ABSTRACT
Pharmacoepidemiological studies commonly examine the association between drug dose and adverse health outcomes. In situations where no safe dose exists, the choice of modeling strategy can lead to identification of an apparent safe low dose range in the presence of a non-linear relationship or due to the modeling strategy forcing a linear relationship through a dose of 0. We conducted a simulation study to assess the performance of several regression approaches to model the drug dose-response curve at low doses in a setting where no safe range exists, including the use of a (1) linear dose term, (2) categorical dose term, and (3) natural cubic spline terms. Additionally, we introduce and apply an expansion of prior work related to modeling dose-response curves at low and infrequently used doses in the setting of no safe dose ("spike-at-zero" and "slab-and-spline"). Furthermore, we demonstrate and empirically assess the use of these regression strategies in a practical scenario examining the association between the dose of the initial postpartum opioid prescribed after vaginal delivery and the subsequent total dose of opioids prescribed in the entire postpartum period among a cohort of opioid-naïve women with a vaginal delivery enrolled in a State Medicaid program (2007-2014).
ABSTRACT
Low vitamin D status is linked with poorer cognition in adults while findings in relation to high levels are mixed.We performed a systematic review and meta-analyses to examine dose-response associations between 25-hydroxyvitamin D (25OHD) levelsand cognitive performance in community-dwelling adults. Thirty-eight observational studies were included in dose-response meta-analyses. Positive, nonlinear associations were identified between baseline25OHD levels and global cognition incross-sectional and longitudinal analyses, and for performance in memory and executive function in longitudinal analyses. When restricted to studies involving older adults, thepattern emerged forspecific domains in cross-sectional analyses. Poorer performance was associated with low 25OHD levels, while a sharp improvement was associated withlevels up to 60-70 nM/L. Further improvement was observed only for longitudinal global cognition. Our findings support the association between low vitamin D and poorer cognition and suggest levels of at least 60 nM/L are associated with better cognition during ageing.
Subject(s)
Independent Living , Vitamin D , Cross-Sectional Studies , Cognition , Executive FunctionABSTRACT
Existing pharmacodynamic (PD) mathematical models for drug combinations discriminate antagonistic, additive, multiplicative, and synergistic effects, but fail to consider how concentration-dependent drug interaction effects may vary across an entire dose-response matrix. We developed a two-way pharmacodynamic (TWPD) model to capture the PD of two-drug combinations. TWPD captures interactions between upstream and downstream drugs that act on different stages of viral replication, by quantifying upstream drug efficacy and concentration-dependent effects on downstream drug pharmacodynamic parameters. We applied TWPD to previously published in vitro drug matrixes for repurposed potential anti-Ebola and anti-SARS-CoV-2 drug pairs. Depending on the drug pairing, the model recapitulated combined efficacies as or more accurately than existing models and can be used to infer efficacy at untested drug concentrations. TWPD fits the data slightly better in one direction for all drug pairs, meaning that we can tentatively infer the upstream drug. Based on its high accuracy, TWPD could be used in concert with PK models to estimate the therapeutic effects of drug pairs in vivo.
Subject(s)
COVID-19 , Hemorrhagic Fever, Ebola , Humans , Models, Biological , SARS-CoV-2 , Hemorrhagic Fever, Ebola/drug therapy , Drug CombinationsABSTRACT
BACKGROUND: Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been suggested as a cognitive enhancing agent, though their effect is doubtful. We aimed to examine the effect of n-3 PUFA on the cognitive function of middle-aged or older adults without dementia. METHODS: We reviewed randomized controlled trials of individuals aged 40 years or older. We systematically searched PubMed/MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Library databases. We used the restricted cubic splines model for non-linear dose-response meta-analysis in terms of the standardized mean difference with 95% confidence intervals. RESULTS: The current meta-analysis on 24 studies (n 9660; follow-up 3 to 36 months) found that the beneficial effect on executive function demonstrates an upward trend within the initial 12 months of intervention. This effect is prominently observed with a daily intake surpassing 500 mg of n-3 PUFA and up to 420 mg of eicosapentaenoic acid (EPA). Furthermore, these trends exhibit heightened significance in regions where the levels of blood docosahexaenoic acid (DHA) + EPA are not very low. CONCLUSIONS: Supplementation of n-3 PUFA may confer potential benefits to executive function among the middle-aged and elderly demographic, particularly in individuals whose dietary DHA + EPA level is not substantially diminished.
Subject(s)
Cognition , Fatty Acids, Omega-3 , Humans , Fatty Acids, Omega-3/administration & dosage , Cognition/drug effects , Cognition/physiology , Randomized Controlled Trials as Topic , Aged , Middle Aged , Adult , Dietary Supplements , Dose-Response Relationship, Drug , Dementia/drug therapyABSTRACT
Cancers represent complex autonomous systems, displaying self-sufficiency in growth signaling. Autonomous growth is fueled by a cancer cell's ability to "secrete-and-sense" growth factors (GFs): a poorly understood phenomenon. Using an integrated computational and experimental approach, here we dissect the impact of a feedback-coupled GTPase circuit within the secretory pathway that imparts secretion-coupled autonomy. The circuit is assembled when the Ras-superfamily monomeric GTPase Arf1, and the heterotrimeric GTPase Giαßγ and their corresponding GAPs and GEFs are coupled by GIV/Girdin, a protein that is known to fuel aggressive traits in diverse cancers. One forward and two key negative feedback loops within the circuit create closed-loop control, allow the two GTPases to coregulate each other, and convert the expected switch-like behavior of Arf1-dependent secretion into an unexpected dose-response alignment behavior of sensing and secretion. Such behavior translates into cell survival that is self-sustained by stimulus-proportionate secretion. Proteomic studies and protein-protein interaction network analyses pinpoint GFs (e.g., the epidermal GF) as key stimuli for such self-sustenance. Findings highlight how the enhanced coupling of two biological switches in cancer cells is critical for multiscale feedback control to achieve secretion-coupled autonomy of growth factors.
Subject(s)
Eukaryotic Cells , Proteomics , Signal Transduction , GTP PhosphohydrolasesABSTRACT
Listeria monocytogenes is the foodborne pathogen responsible for listeriosis in humans. Its ability to grow at refrigeration temperatures, particularly in products that support its growth and have a long-refrigerated shelf-life, poses a significant health risk, especially for vulnerable consumer groups such as pregnant women and immunocompromised individuals. A comprehensive analysis of L. monocytogenes in aquatic food products (AFPs) was conducted, examining the prevalence of the bacterium, the associated outbreaks, and the resulting deaths. Data from 66 studies, comprising a total of 19,373 samples, were analysed from the scientific literature to determine prevalence of the pathogen. The mean pooled prevalence of L. monocytogenes was 11 % (95 % CI: 8-14 %) among different AFPs categories. An overview of worldwide listeriosis outbreaks associated with contaminated AFPs between 1980 and 2023 was provided, totalling 1824 cases, including 41 deaths. Furthermore, a compilation of bio-based mitigation strategies was presented, including the use of lactic acid bacteria (LAB) and bacteriophages as bio-protective cultures to inhibit L. monocytogenes in AFPs. A variety of predictive microbiology models, based on growth prediction and interaction for L. monocytogenes, were reviewed to assess the effectiveness of control strategies in different types of AFPs, offering insights into pathogen behaviour throughout the production chain. The reported growth models describe primarily the impact of storage temperature on pathogen growth parameters, while interaction models, which reflect the inhibitory effect of LAB against L. monocytogenes, were generally defined using the Jameson-effect approach and Lotka-Volterra models' family (i.e., predator-prey models). Both models can be used to describe the simultaneous growth of two bacterial populations and their interactions (i.e., amensalism and antagonisms). Several Quantitative Risk assessment studies have been conducted for AFP, identifying the food category as a relevant contributor to Listeriosis risk, and providing predictive insight critical influence of storage temperature, food microbiota, product shelf-life, and population aging on the risk posed by L. monocytogenes. More importantly, this quantitative approach can serve as a key tool to assess the effectiveness of specific mitigation and intervention strategies to control the pathogen, such as sampling schemes or bio-preservation techniques.
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PURPOSE: Fracture risk assessment is recommended at three months after glucocorticoid (GC) therapy initiation. This study aimed to assess whether GC exposure in the initial 90 days of GC therapy is associated with subsequent hip and clinical vertebral fracture risk using the nationwide health insurance claims database of Japan (NDBJ). METHODS: Patients aged ≥ 50 years who were prescribed GC (≥ 70 mg prednisolone or equivalent; PSL) in the initial 90 days of GC therapy and were followed for hip and clinical vertebral fracture incidences for the subsequent 1080 days were selected from NDBJ. Associations of GC exposure with hip or clinical vertebral fracture risk were evaluated by Cox regression analysis adjusted for potential confounders. RESULTS: We selected 316,396 women and 299,871 men for the GC-exposed group and 43,164 women and 33,702 men for the reference group. Higher GC doses and longer prescription days in the initial 90 days of GC therapy were significantly and dose-dependently associated with increased fracture risk relative to the reference group. Patients receiving GC ≥ 5 mg PSL/day had a significantly increased fracture risk in the stratum of 30-59 days of GC prescription. In addition, female patients who received GC (≥ 1 and < 2.5 mg PSL/day) for 90 days in the initial 90 days of GC therapy had a significantly increased fracture risk. CONCLUSIONS: GC exposure in the initial 90 days of GC therapy was dose-dependently associated with hip and clinical vertebral fracture risk. GC may increase fracture risk with lower doses for shorter durations than previously reported. Fracture risk assessment three months after glucocorticoid (GC) therapy initiation is recommended. We found that GC exposure in the initial 90 days of GC therapy at lower daily doses for shorter durations than previously reported were significantly and dose-dependently associated with fracture risk using a nationwide health insurance claims database.
Subject(s)
Fractures, Bone , Hip Fractures , Spinal Fractures , Male , Humans , Female , Aged , Glucocorticoids/adverse effects , Spinal Fractures/epidemiology , Spinal Fractures/etiology , Retrospective Studies , Japan/epidemiology , Insurance, Health , Hip Fractures/chemically induced , Hip Fractures/epidemiology , Risk FactorsABSTRACT
OBJECTIVE: This study aimed to establish the dose-response relationship between volume base dose and tumor local control for vaginal cancer, including primary vaginal cancer and recurrent gynecologic malignancies in the vagina. MATERIALS AND METHODS: We identified studies that reported volume base dose and local control by searching the PubMed, the Web of Science, and the Cochrane Library Database through August 12, 2023. The regression analyses were performed using probit model between volume based dose versus clinical outcomes. Subgroup analyses were performed according to stratification: publication year, country, inclusion time of patients, patients with prior radiotherapy, age, primaries or recurrent, tumor size, concurrent chemoradiotherapy proportion, dose rate, image modality for planning, and interstitial proportion. RESULTS: A total of 879 patients with vaginal cancer were identified from 18 studies. Among them, 293 cases were primary vaginal cancer, 573 cases were recurrent cancer in the vagina, and 13 cases were unknown. The probit model showed a significant relationship between the HR-CTV (or CTV) D90 versus the 2-year and 3-year local control, P values were 0.013 and 0.014, respectively. The D90 corresponding to probabilities of 90% 2-year local control were 79.0 GyEQD2,10 (95% CI: 75.3-96.6 GyEQD2,10). CONCLUSIONS: A significant dependence of 2-year or 3-year local control on HR-CTV (or CTV) D90 was found. Our research findings encourage further validation of the dose-response relationship of radical radiotherapy for vaginal cancer through protocol based multicenter clinical trials.
Subject(s)
Dose-Response Relationship, Radiation , Radiotherapy Dosage , Vaginal Neoplasms , Humans , Female , Vaginal Neoplasms/radiotherapy , Vaginal Neoplasms/pathology , Neoplasm Recurrence, Local/radiotherapy , Middle Aged , Treatment Outcome , Aged , Vagina/radiation effects , Vagina/pathologyABSTRACT
BACKGROUND: Vitamin A (VA) deficiency and excess negatively affect development, growth, and bone health. The World Health Organization's standard of care for xerophthalmia due to VA deficiency, is 3 high-dose VA supplements of 50,000-200,000 IU, based on age, which may cause hypervitaminosis A in some individuals. OBJECTIVES: This study measured VA status following 3 VA doses in 2 piglet studies. METHODS: In Study 1, 5 groups of piglets (n = 10/group) were weaned 10 d postbirth to VA-free feed and orally administered 0; 25,000; 50,000; 100,000; or 200,000 IU VA ester on days 0, 1, and 7. On days 14 and 15, the piglets underwent the modified relative dose-response (MRDR) test for VA deficiency, and were killed. Tissues were collected for high-pressure liquid chromatography analysis. Study 2 used the same design in 3 groups (n = 13/group) weaned at 16 d and administered 0; 25,000; and 200,000 IU doses. RESULTS: In Study 1 (final weight: 3.6 ± 0.7 kg), liver VA concentration was hypervitaminotic in 40%, 90%, and 100% of 50,000; 100,000; and 200,000 IU groups, respectively. The 25,000 IU group was 100% adequate, and the placebo group was 40% deficient. In Study 2 (final weight: 8.7 ± 0.8 kg), where 200,000 IU could be prescribed to infants with a similar body weight, 31% of the piglets were hypervitaminotic, the 25,000 IU group was 100% VA adequate, and the placebo group was 100% deficient. The MRDR test measured deficiency in 50% and 70% of the placebo group in each study but had 3 false positives among hypervitaminotic piglets in Study 1. CONCLUSIONS: Repeated high-dose VA may cause hypervitaminosis, indicating dose sizes may need reduction. The MRDR resulted in false positives in a hypervitaminotic state during malnutrition and should be paired with serum retinyl ester evaluation to enhance VA status assessment in populations with overlapping interventions.
Subject(s)
Dietary Supplements , Hypervitaminosis A , Vitamin A , Xerophthalmia , Animals , Vitamin A/administration & dosage , Swine , Xerophthalmia/drug therapy , Dose-Response Relationship, Drug , Swine Diseases/drug therapy , Vitamin A Deficiency/drug therapy , Vitamin A Deficiency/veterinary , Female , Male , Liver/metabolism , Liver/drug effectsABSTRACT
OBJECTIVE: This study investigated changes in methylation concentrations within the glutathione peroxidase 3 (GPX3) promoter region among patients diagnosed with chronic heart failure (CHF). Peripheral blood samples were collected from 20 CHF patients and 20 healthy individuals for analysis. METHODS: Using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, methylation concentrations of 11 CpG sites within the GPX3 promoter region were quantified. RESULTS: Results showed a significant increase in methylation at the GPX3_FA10_CpG_24 site in patients with CHF compared with the control group (P < 0.05). Furthermore, a nonlinear dose-response relationship was observed between methylation concentrations at this site and key clinical parameters including serum apolipoprotein A-1, D-dimer, chlorine, potassium, and sodium (Na) (P < 0.05). CONCLUSIONS: These findings suggest that aberrant methylation of the GPX3 promoter may impact disease progression by influencing physiological functions such as blood lipids, coagulation, and electrolytes. Further investigations are warranted to elucidate the role of GPX3 promoter methylation in CHF pathogenesis, potentially contributing valuable insights for its prevention, diagnosis, and treatment.
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BACKGROUND: Smoking is a significant public health concern in China and a leading cause of lung cancer deaths among adults. This study aims to employ three methods to estimate smoking-attributable lung cancer mortality among Chinese adults from 2000 to 2020. METHODS: Population attributable fractions (PAFs) of lung cancer deaths caused by smoking were estimated using lagged smoking prevalence, Peto-Lopez, and dose-response relationship methods, separately. Smoking exposure was obtained from national tobacco surveys in China, and relative risks (RR) were derived from a meta-analysis of state-of-the-art studies among the Chinese population. Finally, we estimated the sex- and age-stratified smoking-attributable lung cancer deaths in Chinese population in 2000, 2005, 2010, 2015, and 2020. RESULTS: The PAFs estimated using 5- and 10-year lagged smoking prevalence method (45-47%) and Peto-Lopez method (46-47%) were similar, while PAFs calculated using the dose-response method were highest (47-58%). The PAFs were consistently higher in males than in females. Age-specific PAFs estimated by lagged smoking prevalence method (54-60%) and the Peto-Lopez method (57-61%) in males were similar and relatively stable, with slight decreases in older populations, while the dose-response relationship-based PAFs increased with age and fluctuated by year. By using the above methods, smoking-attributable lung cancer deaths were estimated to be 134,100, 134,600, 136,600, and 155,300 in 2000 increasing to 310,300, 301,100, 306,000, and 314,700 in 2020, respectively. CONCLUSION: The estimation from dose-response methods could better reflect the smoking effect, however, high-quality data and accurate estimation of parameters are necessary.
Subject(s)
Lung Neoplasms , Adult , Female , Humans , Male , China/epidemiology , Lung Neoplasms/epidemiology , Lung Neoplasms/etiology , Smoking/adverse effects , Smoking/epidemiology , Tobacco SmokingABSTRACT
BACKGROUND: Although substantial efforts have been made to build molecular biomarkers to predict radiation sensitivity, the ability to accurately stratify the patients is still limited. In this study, we aim to leverage large-scale radiogenomics datasets to build genomic predictors of radiation response using the integral of the radiation dose-response curve. METHODS: Two radiogenomics datasets consisting of 511 and 60 cancer cell lines were utilized to develop genomic predictors of radiation sensitivity. The intrinsic radiation sensitivity, defined as the integral of the dose-response curve (AUC) was used as the radioresponse variable. The biological determinants driving AUC and SF2 were compared using pathway analysis. To build the predictive model, the largest and smallest datasets consisting of 511 and 60 cancer cell lines were used as the discovery and validation cohorts, respectively, with AUC as the response variable. RESULTS: Utilizing a compendium of three pathway databases, we illustrated that integral of the radiobiological model provides a more comprehensive characterization of molecular processes underpinning radioresponse compared to SF2. Furthermore, more pathways were found to be unique to AUC than SF2-30, 288 and 38 in KEGG, REACTOME and WIKIPATHWAYS, respectively. Also, the leading-edge genes driving the biological pathways using AUC were unique and different compared to SF2. With regards to radiation sensitivity gene signature, we obtained a concordance index of 0.65 and 0.61 on the discovery and validation cohorts, respectively. CONCLUSION: We developed an integrated framework that quantifies the impact of physical radiation dose and the biological effect of radiation therapy in interventional pre-clinical model systems. With the availability of more data in the future, the clinical potential of this signature can be assessed, which will eventually provide a framework to integrate genomics into biologically-driven precision radiation oncology.