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Tao, Y.

Publications and source records attributed to Tao, Y..

11 recordsLinked to original sources

Effects of age on the green autofluorescence of the skin and fingernails of healthy persons

Our recent studies have suggested that altered Pattern of Autofluorescence (AF) of skin and fingernails are novel biomarkers of multiple major diseases. The age of all of the subjects in these studies ranges from 50 to 80 years of old. For future studies on the potential diagnostic value of green AF for age-independent diseases, it is required to answer the following question: Are there differences in the green AF of healthy persons of various age populations? In our current study, we determined the green AF of the skin and fingernails of healthy persons in several age populations, showing significant age dependence of the AF: First, the green AF intensity of the age group between 15 to 20 years of old is significantly higher than that of the age group between 50 to 80 years of old at both right and left Centremetacarpus, right Dorsal Centremetacarpus, and right Dorsal Index Finger. Second, for the green AF intensity of the age groups of 15 to 20 years of old, 60 to 70 years of old, 70 to 80 years of old, and 81 to 85 years of old, the green AF intensity is negatively correlated with the age at both right and left Centremetacarpus and right Dorsal Centremetacarpus. Collectively, our study has provided first evidence indicating the age dependence of the AF intensity of humans skin, which has established essential basis for the studies that determine the diagnostic value of the green AF for the age-independent diseases.

physiology

Automatic Human-like Mining and Constructing Reliable Genetic Association Database with Deep Reinforcement Learning

The increasing amount of scientific literature in biological and biomedical science research has created a challenge in the continuous and reliable curation of the latest knowledge discovered, and automatic biomedical text-mining has been one of the answers to this chal-lenge. In this paper, we aim to further improve the reliability of biomedical text-mining by training the system to directly simulate the human behaviors such as querying the PubMed, selecting articles from queried results, and reading selected articles for knowledge. We take advantage of the efficiency of biomedical text-mining, the flexibility of deep reinforcement learning, and the massive amount of knowledge collected in UMLS into an integrative arti-ficial intelligent reader that can automatically identify the authentic articles and effectively acquire the knowledge conveyed in the articles. We construct a system, whose current pri-mary task is to build the genetic association database between genes and complex traits of the human. Our contributions in this paper are three-fold: 1) We propose to improve the reliability of text-mining by building a system that can directly simulate the behavior of a researcher, and we develop corresponding methods, such as Bi-directional LSTM for text mining and Deep Q-Network for organizing behaviors. 2) We demonstrate the effec-tiveness of our system with an example in constructing a genetic association database. 3) We release our implementation as a generic framework for researchers in the community to conveniently construct other databases.

bioinformatics

Green autofluorescence intensity of skin and fingernails: A novel biomarker for non-invasive evaluation of pathological state of blood vessels

Stroke and myocardial infarction (MI) are two leading causes of death around the world. It is of great significance to establish novel and non-invasive approaches for evaluating pathological state of blood vessels, so that early interventions may be carried out to prevent incidence of stroke or MI. Our recent studies have suggested that altered Pattern of Autofluorescence (AF) of skin and fingernails are novel biomarkers of acute ischemic stroke (AIS) and MI. In particular, our studies have shown characteristic increases in the green AF intensity of the fingernails and certain regions of the skin of AIS patients and MI patients. By determining the skins green AF of the Healthy Group, the Low-Risk Group for Developing AIS, and the High-Risk Group for Developing AIS, our current study has indicated that the green AF intensity in the fingernails and certain regions of the skin, including the right and left Dorsal Index Fingers, Ventroforefingers, Dorsal Antebrachium and Index Fingernails as well as right Dorsal Centremetacarpus, is highly correlated with the risk to develop AIS. There is also evidence suggesting that increased oxidative stress may account for the increased AF intensity in the Low-Risk Group for Developing AIS and the High-Risk Group for Developing AIS. These findings have suggested that the green AF intensity of the fingernails and certain regions of the skin is a novel biomarker for non-invasive evaluation of the pathological state of blood vessels and the risk for developing AIS or MI.

pathology

Calcium nanodomains in spindles

The role of calcium signaling in specific events of animal cell meiosis or mitosis (M-phase) is a subject of enduring controversy. Early efforts suggested that increases in intracellular free calcium ([Ca2+]i) promote spindle disassembly 1, 2 while subsequent work suggested that global [Ca2+]i increases trigger nuclear envelope breakdown, spindle assembly, the metaphase-anaphase transition, and cytokinesis 3-6. However, further studies led to the conclusion that elevation of [Ca2+]i either has no role in these events, plays a permissive role in these events, or functions as an auxiliary signaling pathway that supplements other mechanisms 7. One potential explanation of the controversy is that specific M-phase events might depend on highly localized increases in [Ca2+]i, variously referred to as microdomains 8 or nanodomains 9, as proposed recently 10. Such domains are hypothesized to arise from rapid shuttling of calcium between closely positioned sources and sinks, rendering them potentially difficult to detect with traditional dyes and largely insensitive to slow chelators such as EGTA 9. Here a novel microtubule-binding calcium sensor--TubeCamp--was used to test the hypothesis 10 that spindles are associated with calcium nanodomains. TubeCamp imaging revealed that spindles in Xenopus eggs, Xenopus embryos, and HeLa cells were all associated with calcium nanodomains at the spindle poles. Calcium nanodomains also formed in spindles assembled in cell extracts and at the center of monopolar spindles, suggesting that they are a basic feature of spindle self-assembly. Disruption of calcium nanodomains via perturbation of inositol-1,4,5-trisphosphate signaling or rapid chelation of [Ca2+]i resulted in spindle disassembly in vivo and vitro. The results demonstrate the existence of spindle-associated calcium nanodomains and indicate that such domains are an essential and common feature of spindles in vertebrates.

cell biology

Decreased green autofluorescence intensity of lung parenchyma is a potential non-invasive diagnostic biomarker for lung cancer

Early and non-invasive diagnosis is critical for enhancing the survival rates of lung cancer. In current study we determined the green autoflorescence (AF) of the pulmonary parenchyma of lung cancer patients, using 488 nm and 500 - 550 nm as excitation wavelength and emission wavelength, respectively. Our study has suggested that decreased green AF intensity of pulmonary parenchyma may be a potential diagnostic biomarker for lung cancer: First, the green AF intensity of the cancerous tissues is less than 40% of those of distant non-neoplastic tissues and peri-neoplastic tissues; second, the green AF intensity of both the distant non-neoplastic tissues and cancerous tissues of squamous carcinoma is significantly lower than that of adenocarcinoma; third, the AF intensity of the peri-neoplastic tissues of the lung cancer patients is negatively correlated with the stages of lung cancer; and fourth, our study on the AF spectrum of pulmonary parenchyma has suggested that the AF may result from the AF of the keratins or FAD of the pulmonary parenchyma. Collectively, our study has suggested that decreased green AF intensity of pulmonary parenchyma may become a novel biomarker for non-invasive diagnosis of lung cancer. The green AF intensity may also be used to non-invasively differentiate squamous carcinoma and adenocarcinoma, as well as the stages of lung cancer. Moreover, our diagnostic approach for lung cancer may be used for image-guided surgery of lung cancer for lesions that have not been identified by CT.

biophysics

Distinct Patterns of the Autofluorescence of Body Surface: Potential Novel Diagnostic Biomarkers for Stable Coronary Artery Disease and Myocardial Infarction

Searches for new biomarkers of stable coronary artery disease (SCAD) and myocardial infarction (MI) are critical for therapeutic efficacy of the diseases. In this study we tested our hypothesis that distinct patterns of autofluorescence (AF) of skin and fingernails may become novel diagnostic biomarkers for MI and SCAD. Our study has indicated that SCAD and MI have distinct patterns of AF of their body surface: First, the AF intensity of the MI patients is significantly higher than that of the Healthy and Low-Risk group in their right and left Centremetacarpus, Ventroforefinger, Dorsal Index Finger and Ventribrachium, while the AF intensity of the SCAD patients is significantly higher than that of the Healthy and Low-Risk group in their right and left Index Fingernails and Dorsal Antebrachium; and second, the AF asymmetry of the MI patients is significantly higher than that of the Healthy and Low-Risk group in their Centremetacarpus, Ventroforefinger, Index Fingernails and Dorsal Antebrachium, while the AF asymmetry of the SCAD patients is significantly higher than that of the Healthy and Low-Risk group in their Ventroforefinger, Dorsal Index Finger, Dorsal Centremetacarpus and Index Fingernails. Moreover, the AF pattern of acute ischemic stroke is markedly different from those of SCAD and MI. The oxidative stress in the plasma of the MI and SCAD patients may cause the increased AF by altering the AF of keratins. Collectively, our study has indicated that SCAD and MI patients have distinct patterns of AF changes, which may become novel diagnostic biomarkers for SCAD and MI.

biophysics

Selectively increased autofluorescence at fingernails and certain regions of skin: A potential novel diagnostic biomarker for Parkinson disease

Diagnosis of Parkinsons disease (PD) mainly relies on the judgment of experienced neurologists on the clinical symptoms of patients. Quantitative and specific biomarker tests for PD is greatly needed. In this study we tested our hypothesis that increased autofluorescence (AF) of skin and fingernails may become a novel diagnostic biomarker for PD. Our study has indicated that PD patients have a distinct pattern of AF changes, compared with that of acute ischemic stroke (AIS) patients: First, the AF intensity of PD patients in the fingernails and a part of the examined regions of skin is significantly higher than that of the healthy and Low-Risk group, while the AF intensity of AIS patients is significantly higher than that of the healthy and Low-Risk group in most regions examined; second, there is AF asymmetry at the index fingernails and two regions of the skin of PD patients, while there is AF asymmetry at all examined regions of AIS patients; and third, both the AF intensity and AF asymmetry at Centremetacarpus of PD patients is significantly lower than those of AIS patients. The increased AF may result from the altered keratins AF induced by the oxidative stress in the plasma of PD patients. Collectively, our study has indicated that PD patients have a distinct pattern of AF changes compared with those of healthy and Low-Risk persons as well as AIS patients, which may become a novel diagnostic biomarker for PD.

neuroscience

Selectively increased autofluorescence at certain regions of skin may become a novel diagnostic biomarker for lung cancer

Early diagnosis is critical for improving the 5-year survival rate of lung cancer patients. Our current study tested our hypothesis that increased autofluorescence (AF) of skin and nails may become a novel diagnostic biomarker of lung cancer, which has generated the following findings: First, our study on a mouse model of lung cancer has shown that development of lung cancer led to a marked increase in the epidermal green AF of the mice. Second, the AF intensity of the untreated lung cancer patients was significantly higher than that of the healthy persons and the pulmonary infection patients at certain examined locations of the skin and fingernails. Third, the ‘Pattern of AF’ of healthy controls, pulmonary infection patients and untreated lung cancer patients was markedly different from each other. Fourth, when the number of the locations with increased AF was used as the sole diagnostic parameter, our ROC analysis showed that the AUC was 0.9067 for differentiating the healthy controls and the untreated lung cancer patients. Collectively, our study has indicated that development of lung cancer is sufficient to induce increases in the epidermal green AF of both mice and human subjects. Our study has also indicated that the ‘Pattern of AF’ of lung cancer patients could become a novel biomarker of lung cancer, which holds great promise for non-invasive, rapid and economic diagnosis and screening of lung cancer.Competing Interest StatementThe authors have declared no competing interest.View Full Text

cancer biology

Asymmetric increases in the intensity of the green autofluorescence of ischemic stroke patients’ skin and fingernails: A novel diagnostic biomarker for ischemic stroke

AbstractEarly and economical diagnosis of acute ischemic stroke (AIS) is pivotal for therapeutic efficacy, particularly for the settings where medical imaging resource is deficient. We have obtained evidence supporting our hypothesis that collective properties of the green autofluorescence (AF) of the fingernails and certain skins positions may be a novel diagnostic biomarker for AIS: Both the green AF intensity and AF asymmetry of the AIS patients in their Index Fingernails and most examined skins positions were significantly higher than that of the healthy subjects and the Non-AIS subjects. ROC analyses and machine learning-based analyses on the AF properties showed that AUC was 0.93 and 0.87, respectively, for differentiating the AIS patients from the healthy subjects and for differentiating the AIS patients from the Non-AIS subjects. The AIS patients had significantly higher AF intensity and AF asymmetry at several examined positions, compared to those of the patients of Parkinsons disease, pulmonary infection and transient ischemic attack. The AUC was 0.79 - 0.88 for differentiating AIS patients from each of these diseases. There was evidence suggesting that the AF originates from keratins. Collectively, our study has indicated that the characteristic AISs Pattern of AF is a novel diagnostic biomarker for the disease. The Pattern of AF Technology holds excellent potential to become a new non-invasive, label-free and economical diagnostic approach for AIS, which is particularly valuable when MRI or CT imaging resource is deficient.

neuroscience

Genetic load and mutational meltdown in cancer cell populations

ABSRACTLarge and non-recombining genomes are prone to accumulating deleterious mutations faster than natural selection can purge (Mullers ratchet). A possible consequence would then be the extinction of small populations. Relative to most single-cell organisms, cancer cells, with large and non-recombining genomes, could be particularly susceptible to such \"mutational meltdown\". Curiously, deleterious mutations in cancer cells are rarely noticed despite the strong signals in cancer genome sequences. Here, by monitoring single-cell clones from HeLa cell lines, we characterize deleterious mutations that retard cell proliferation. The main mutational events are copy number variations (CNVs), which happen at an extraordinarily high rate of 0.29 events per cell division. The average fitness reduction, estimated to be 18% per mutation, is also very high. HeLa cell populations therefore have very substantial genetic load and, at this level, natural population would likely experience mutational meltdown. We suspect that HeLa cell populations may avoid extinction only after the population size becomes large. Because CNVs are common in most cell lines and cancer tissues, the observations hint at cancer cells vulnerability, which could be exploited by therapeutic strategies.

evolutionary biology

Tuning the course of evolution on the biophysical fitness landscape of an RNA virus

Predicting viral evolution remains a major challenge with profound implications for public health. Viral evolutionary pathways are determined by the fitness landscape, which maps viral genotype to fitness. However, a quantitative description of the landscape and the evolutionary forces on it remain elusive. Here, we apply a biophysical fitness model based on capsid folding stability and antibody binding affinity to predict the evolutionary pathway of norovirus escaping a neutralizing antibody. The model is validated by experimental evolution in bulk culture and in a drop-based microfluidics device, the \"Evolution Chip\", which propagates millions of independent viral sub-populations. We demonstrate that along the axis of binding affinity, selection for escape variants and drift due to random mutations have the same direction. However, along folding stability, selection and drift are opposing forces whose balance is tuned by viral population size. Our results demonstrate that predictable epistatic tradeoffs shape viral evolution.

evolutionary biology