Publications by authors named "Yilin Huang"

16 Publications

  • Page 1 of 1

Significant Difference of Immune Cell Fractions and Their Correlations With Differential Expression Genes in Parkinson's Disease.

Front Aging Neurosci 2021 17;13:686066. Epub 2021 Aug 17.

School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China.

Parkinson's disease (PD) is the second most neurodegenerative disease in the world. T cell infiltration in the central nervous system (CNS) has provided insights that the peripheral immune cells participate in the pathogenesis of PD. However, the association between the peripheral immune system and CNS remains to be elucidated. In this study, we analyzed incorporative substantia nigra (SN) expression data and blood expression data using the CIBERSORT to obtain the 22 immune cell fractions and then explored the molecular function to identify the potential key immune cell types and genes of PD. We observed that the proportions of naïve CD4 T cells, gamma delta T cells, resting natural killer (NK) cells, neutrophils in the blood, and regulatory T cells (Tregs) in the SN were significantly different between patients with PD and healthy controls (HCs). We identified p53-induced death domain protein 1 () as the hub gene of a PD-related module. The enrichment score of the neuron-specific gene set was significantly different between PD and HC, and genes in the neuron-related module were enriched in the biological process about mitochondria and synapses. These results suggested that the fractions of naïve CD4 T cells, gamma delta T cells, resting NK cells, and neutrophils may be used as a combined diagnostic marker in the blood, and Tregs in SN may be a potential therapeutic design target for PD.
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http://dx.doi.org/10.3389/fnagi.2021.686066DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8416258PMC
August 2021

Bone Marrow Metastases From Gastric Adenocarcinoma on 68Ga-FAPI-04 PET/CT.

Clin Nucl Med 2021 Jul 26. Epub 2021 Jul 26.

From the Department of Nuclear Medicine, the Affiliated Hospital of Southwest Medical University; Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province; and Academician (Expert) Workstation of Sichuan Province, Luzhou, China.

Abstract: A 37-year-old woman complained of fatigue and dizziness for 4 days. Bone marrow biopsy findings were suggestive of digestive tract-derived metastases. 18F-FDG PET/CT revealed mild FDG avidity in the stomach and bone marrow, whereas 68Ga-FAPI-04 PET/CT showed strong FAPI uptake in the FDG-avid lesions. The patient was diagnosed with bone marrow metastases from gastric cancer by a bone marrow biopsy.
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http://dx.doi.org/10.1097/RLU.0000000000003839DOI Listing
July 2021

An anion exchange pretreatment method for the determination of low-level uranium in the environmental water samples.

J Environ Radioact 2021 Oct 17;237:106699. Epub 2021 Jul 17.

School of Nuclear Science and Technology, University of South China, 28 Changsheng West Road, Hengyang 421001, PR China. Electronic address:

Uranium in environmental water is usually at trace or ultra-trace levels with high concentrations of background ions so that the detection of uranium often couples with pretreatment processes to lower the detection limit, and improve the selectivity and accuracy of instruments. A simple, green, effective and efficient anion exchange pretreatment method was proposed to favor the determination of low-level uranium in natural environmental water samples. To determine the applicability and obtain the optimum operating parameters, the effects of coprecipitation, pH, contact time, uranium concentration, background ions, eluent and the flow speed on the uranium recovery were investigated. The experimental results showed that the proper addition of saturated NaCO solution for pH adjustment did not lead to uranium loss in natural water samples, and the optimum pH value for adsorption was determined from 6 to 8. The adsorption speed was improved a lot with the employment of a novel silica-supported anion exchange resin, which also showed good linear dependence in the concentration range from <0.5 μg/L to 1000 μg/L with high tolerance limits towards common background ions. The optimum eluent was determined as 1 M HNO, and the optimum flow speeds for adsorption and desorption were about 4.0 and 1.0 mL/min, respectively. Based on these results, a pretreatment process was finally established, which realized the quantitative recovery of uranium from six different natural water samples with the chemical yields exceeding 95% and the enrichment factors about 100 times.
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http://dx.doi.org/10.1016/j.jenvrad.2021.106699DOI Listing
October 2021

Chronic Colitis Mimicking Malignancy on 68Ga-FAPI PET/CT.

Clin Nucl Med 2021 Jul 6. Epub 2021 Jul 6.

From the Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province Academician (Expert) Workstation of Sichuan Province Department of Pathology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.

Abstract: A 40-year-old man presented with abdominal pain and diarrhea for 2 months. Abdominal CT showed thickening of the cecal wall, which was considered likely malignant. The patient was subsequently enrolled in a clinical trial of 68Ga-FAPI PET/CT study in tumors. Intense 68Ga-FAPI activity was noted in the thickened cecum, also suggestive of malignancy. However, pathological examination from biopsy rendered a diagnosis of chronic colitis.
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http://dx.doi.org/10.1097/RLU.0000000000003793DOI Listing
July 2021

Associations between coronary heart disease and risk of cognitive impairment: A meta-analysis.

Brain Behav 2021 05 20;11(5):e02108. Epub 2021 Mar 20.

Affiliated of Hospital of Nanjing University of Chinese Medicine, Nanjing, China.

Background: Several studies have demonstrated that coronary heart disease (CHD) is a high risk factor for cognitive impairment, whereas other studies showed that there was no association between cognitive impairment and CHD. The relationship between CHD and cognitive impairment is still unclear based on these conflicting results. Thus, it is of importance to evaluate the association between CHD and cognitive impairment. The present study made a meta-analysis to explore the association between CHD and risk of cognitive impairment.

Methods: Articles exploring the association between CHD and cognitive impairment and published before November 2020 were searched in the following databases: PubMed, Web of Science, Medline, EMBASE, and Google Scholar. We used STATA 12.0 software to compute the relative risks (RRs), odds ratios (ORs), or hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: The meta-analysis showed a positive association between CHD and risk of all-cause cognitive impairment with a random effects model (RR = 1.27, 95% CI 1.18 to 1.36, I  = 82.8%, p < .001). Additionally, the study showed a positive association between myocardial infraction (MI) and risk of all-cause cognitive impairment with a random effects model (RR = 1.49, 95% CI 1.20 to 1.84, I  = 76.0%, p < .001). However, no significant association was detected between angina pectoris (AP) and risk of all-cause cognitive impairment with a random effects model (RR = 1.23, 95% CI 0.95 to 1.58, I  = 79.1%, p < .001). Subgroup studies also showed that CHD patients are at higher risk for vascular dementia (VD), but not Alzheimer's disease (AD) (VD: RR = 1.34, 95% CI: 1.28-1.39; AD: RR = 0.99, 95% CI: 0.92-1.07).

Conclusion: In a word, CHD was significantly associated with an increased risk of developing cognitive impairment.
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http://dx.doi.org/10.1002/brb3.2108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8119850PMC
May 2021

Family function fully mediates the relationship between social support and perinatal depression in rural Southwest China.

BMC Psychiatry 2021 03 12;21(1):151. Epub 2021 Mar 12.

West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu, 610041, China.

Background: Perinatal depression is the most common complication of gestation and childbearing affecting women and their families, and good social support and family function are considered protective and modifiable factors. This study aimed to investigate depression status and explore inter-relationships between social support and perinatal depression considering the influence of family function in rural areas of Southwest China.

Methods: This is a cross-sectional study. The following instruments were used: the Edinburgh Postpartum Depression Scale, the APGAR Family Care Index Scale, and the Social Support Rate Scale. A structural equation modelling was used to test the hypothesis relationships among the variables.

Results: A total of 490 rural antenatal (N = 249) and postpartum (N = 241) women (mean age (standard deviation), 28.17 ± 5.12) participated. We found that the prevalence of depression symptoms was 10.4%. Path analysis showed that family function had a direct negative correlation with depression (β = - 0.251, 95%CI: - 0.382 to - 0.118). Social support had a direct positive correlation with family function (β =0.293, 95%CI: 0.147 to 0.434) and had an indirect negative correlation with depression (β = - 0.074, 95%CI: - 0.139 to - 0.032), family function fully mediated the relationship between social support and depression.

Conclusions: Findings of this study highlight that family function should be considered as the key target for interventions aiming to lower the prevalence of perinatal depression. Family members interventions are critical to reduce depression among antenatal and postpartum women.
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http://dx.doi.org/10.1186/s12888-021-03155-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7953569PMC
March 2021

Predictors of mortality in COPD exacerbation cases presenting to the respiratory intensive care unit.

Respir Res 2021 Mar 4;22(1):77. Epub 2021 Mar 4.

Department of Respiratory and Critical Care Medicine, Beijing Hospital, Beijing, China.

Background: Studies report high in-hospital mortality of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) especially for those requiring admission to an intensive care unit. Recognizing factors associated with mortality in these patients could reduce health care costs and improve end-of-life care.

Methods: This retrospective study included AECOPD patients admitted to the respiratory intensive care unit of a tertiary hospital in Beijing from Jan 1, 2011 to Dec 31, 2018. Patients demographic characteristics, blood test results and comorbidities were extracted from the electronic medical record system and compared between survivors and non-survivors.

Results: We finally enrolled 384 AECOPD patients: 44 (11.5%) patients died in hospital and 340 (88.5%) were discharged. The most common comorbidity was respiratory failure (294 (76.6%)), followed by hypertension (214 (55.7%)), coronary heart disease (115 (29.9%)) and chronic heart failure (76 (19.8%)). Multiple logistic regression analysis revealed that independent risk factors associated with in-hospital mortality included lymphocytopenia, leukopenia, chronic heart failure and requirement for invasive mechanical ventilation.

Conclusions: The in-hospital mortality of patients with acute COPD exacerbation requiring RICU admission is high. Lymphocytes < 0.8 × 10/L, leukopenia, requirement for invasive mechanical ventilation, and chronic heart failure were identified as risk factors associated with increased mortality rates.
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http://dx.doi.org/10.1186/s12931-021-01657-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7930515PMC
March 2021

Multiregion single-cell sequencing reveals the transcriptional landscape of the immune microenvironment of colorectal cancer.

Clin Transl Med 2021 01;11(1):e253

Department of General Surgery, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China.

The tumor microenvironment is a complex ecosystem formed by distinct and interacting cell populations, and its composition is related to cancer prognosis and response to clinical treatment. In this study, we have taken the advantage of two single-cell RNA sequencing technologies (Smart-seq2 and DNBelab C4) to generate an atlas of 15,115 immune and nonimmune cells from primary tumors and hepatic metastases of 18 colorectal cancer (CRC) patients. We observed extensive changes in the proportions and functional states of T cells and B cells in tumor tissues, compared to those of paired non-tumor tissues. Importantly, we found that B cells from early CRC tumor were identified to be pre-B like expressing tumor suppressors, whereas B cells from advanced CRC tumors tended to be developed into plasma cells. We also identified the association of IgA IGLC2 plasma cells with poor CRC prognosis, and demonstrated a significant interaction between B-cell and myeloid-cell signaling, and found CCL8 cycling B cells/CCR5 T-cell interactions as a potential antitumoral mechanism in advanced CRC tumors. Our results provide deeper insights into the immune infiltration within CRC, and a new perspective for the future research in immunotherapies for CRC.
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http://dx.doi.org/10.1002/ctm2.253DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7775989PMC
January 2021

Prevalence and Risk Factors for COPD at High Altitude: A Large Cross-Sectional Survey of Subjects Living Between 2,100-4,700 m Above Sea Level.

Front Med (Lausanne) 2020 3;7:581763. Epub 2020 Dec 3.

National Clinical Research Center for Respiratory Diseases, Beijing, China.

Four hundred million people live at high altitude worldwide. Prevalence and risk factors for COPD in these populations are poorly documented. We examined the prevalence and risk factors for COPD in residents living at an altitude of 2,100-4,700 m. We performed a cross-sectional survey in Xinjiang and Tibet autonomous region. A multistage stratified sampling procedure was used to select a representative population aged 15 years or older from eight high altitude regions. All participants underwent pre- and post-bronchodilator measurement of forced expiratory volumes. COPD was diagnosed according to 2019 Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. Between June, 2015 and August 2016, 4,967 subjects were included. Median age was 38.0 years (range: 15-91 years; inter-quartile range: 28-49 years); 51.4% participants were female. Overall prevalence of spirometry-defined COPD was 8.2% (95% CI 7.4-8.9%): 9.3% in male (95% CI 8.2-10.4%), and 7.1% in female (95% CI 6.1-8.2%). By multivariable logistic regression analysis, COPD was significantly associated with being aged ≥40 years (odds ratio: 2.25 [95% CI 1.72-2.95], < 0.0001), exposure to household air pollution (OR: 1.34 [95% CI 1.01-1.79], = 0.043), and a history of tuberculosis (OR: 1.79 [95% CI 1.23-2.61], = 0.030), while living at a higher altitude (OR: 0.45 [95% CI 0.33-0.61], < 0.0001) and having a higher educational level (OR: 0.64 [95% CI 0.43-0.95], = 0.025) were associated with a lower prevalence of COPD. Our results show that the spirometry-defined COPD is a considerable health problem for residents living at high altitudes and COPD prevalence was inversely correlated with altitude. Preventing exposure to household air pollution and reducing the incidence of tuberculosis should be public health priorities for high altitude residents.
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http://dx.doi.org/10.3389/fmed.2020.581763DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7744817PMC
December 2020

Characterization of a pathogenic variant in GBA for Parkinson's disease with mild cognitive impairment patients.

Mol Brain 2020 07 8;13(1):102. Epub 2020 Jul 8.

School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China.

Parkinson's disease (PD) is the second most common neurodegenerative disease, and mild cognitive impairment (MCI) is a well-established risk factor for the development of dementia in PD. A growing body of evidence suggests that low expression of glucocerebrosidase (GBA) promotes the transmission of α-synuclein (α-Syn) interpolymers and the progression of PD. However, how GBA mutations affect the pathogenesis of PD via abnormal aggregation of α-Syn is unclear, and no clinically valid PD-MCI genetic markers have been identified. Here, we first located a GBA eQTL, rs12411216, by analysing DHS, eQTL SNP, and transcription factor binding site data using the UCSC database. Subsequently, we found that rs12411216 was significantly associated with PD-MCI (P < 0.05) in 306 PD patients by genotyping. In exploring the relationship between rs12411216 and GBA expression, the SNP was found to be associated with GBA expression in 50 PD patients through qPCR verification. In a further CRISPR/Cas9-mediated genome editing module, the SNP was identified to cause a decrease in GBA expression, weaken enzymatic activity and enhance the abnormal aggregation of α-Syn in SH-SY5Y cells. Additionally, using an electrophoretic mobility shift assay, we confirmed that the binding efficiency of transcription factor E2F4 was affected by the rs12411216 SNP. In conclusion, our results showed that rs12411216 regulated GBA expression, supporting its potential role as a PD-MCI genetic biomarker and highlighting novel mechanisms underlying Parkinson's disease.
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http://dx.doi.org/10.1186/s13041-020-00637-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7346430PMC
July 2020

Metabolism and Toxicity of Emodin: Genome-Wide Association Studies Reveal Hepatocyte Nuclear Factor 4α Regulates UGT2B7 and Emodin Glucuronidation.

Chem Res Toxicol 2020 07 7;33(7):1798-1808. Epub 2020 Jul 7.

State Key Laboratory of Organ Failure Research, National Clinical Research Center of Kidney Disease, Division of Nephrology, Southern Medical University, Guangzhou 510515, China.

Emodin is the main toxic component in Chinese medicinal herbs such as rhubarb. Our previous studies demonstrated that genetic polymorphisms of UDP-glucuronosyltransferase 2B7 (UGT2B7) had an effect on the glucuronidation and detoxification of emodin. This study aimed to reveal the transcriptional regulation mechanism of UGT2B7 on emodin glucuronidation and its effect on toxicity. Emodin glucuronic activity and genome and transcriptome data were obtained from 36 clinical human kidney tissues. The genome-wide association studies (GWAS) identified that four single nucleotide polymorphisms (SNPs) (rs6093966, rs2868094, rs2071197, and rs6073433), which were located on the hepatocyte nuclear factor 4α (HNF4A) gene, were significantly associated with the emodin glucuronidation ( < 0.05). Notably, rs2071197 was significantly associated with the gene expression of HNF4A and UGT2B7 and the glucuronidation of emodin. The gene expression of HNF4A showed a high correlation with UGT2B7 ( = 0.721, = 5.83 × 10). The luciferase activity was increased 7.68-fold in 293T cells and 2.03-fold in HepG2 cells, confirming a significant transcriptional activation of UGT2B7 promoter by HNF4A. The knockdown of HNF4A in HepG2 cells (36.6%) led to a significant decrease of UGT2B7 (19.8%) and higher cytotoxicity ( < 0.05). The overexpression of HNF4A in HepG2 cells (31.2%) led to a significant increase of UGT2B7 (24.4%) and improved cell viability ( < 0.05). Besides, HNF4A and UGT2B7 were both decreased in HepG2 cells and rats after treatment with emodin. In conclusion, emodin used long term or in high doses could inhibit the expression of HNF4A, thereby reducing the expression of UGT2B7 and causing hepatotoxicity.
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http://dx.doi.org/10.1021/acs.chemrestox.0c00047DOI Listing
July 2020

SPC25 may promote proliferation and metastasis of hepatocellular carcinoma via p53.

FEBS Open Bio 2020 07 7;10(7):1261-1275. Epub 2020 Jun 7.

Department of Hepatology, The Third People's Hospital of Shenzhen, Shenzhen, China.

Hepatocellular carcinoma (HCC) is a common malignancy with poor prognosis and high mortality. To identify key genes associated with HCC and the underlying mechanisms, we performed weighted correlation network analysis (WGCNA) of potential key genes of HCC. We identified 17 key genes closely related to HCC by yellow module combined with PPI analysis. Verification of the role of these genes revealed that SPC25 knockdown results in a significant decrease in proliferation and metastasis of HCC cells and increased protein levels of components of the p53 pathway in vitro. In summary, we identified that SPC25 is a potential tumor-promoting factor in HCC and may act via the p53 pathway.
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http://dx.doi.org/10.1002/2211-5463.12872DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7327911PMC
July 2020

Mortality of Different Stages of Plodia interpunctella (Lepidoptera: Pyralidae) at Three Temperatures in Controlled Atmosphere of High Nitrogen.

J Econ Entomol 2020 06;113(3):1105-1109

Collaborative Innovation Center of Henan Grain Crops, Henan Collaborative Innovation Center of Grain Storage and Security, Henan University of Technology, Zhengzhou, Henan, China.

The lethal exposure time to controlled atmospheres of high nitrogen at stored grain temperatures is an important information for control of stored-product insects. The mortality of 1-d-old egg, 1-wk-old (first or second instar) larva, 3-wk-old (fourth or fifth instar) larva, and 1-d-old pupa of Plodia interpunctella (Hübner) was determined at 18 ± 1, 23 ± 1, and 28 ± 1°C in 98% N2 mixed with air. At 18°C, the lethal exposure times to achieve 100% mortality were 12.7 ± 0.7, 16.3 ± 0.3, 19.7 ± 0.7, and 14.7 ± 0.7 d for 1-d-old egg, 1-wk-old larva, 3-wk-old larva, and 1-d-old pupa, respectively. Temperature had significant effect on the lethal exposure time, and increase of the temperature significantly decreased the lethal exposure time. The order of the insect stages from the highest to lowest for LT50 values was follows: 3-wk-old larva > 1-wk-old larva > 1-d-old pupa ≥ 1-d-old egg. The minimum lethal exposure times required to kill all stages of P. interpunctella were about 20, 16, and 12 d at 18, 23, and 28°C, respectively.
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http://dx.doi.org/10.1093/jee/toaa038DOI Listing
June 2020

E-Cigarette Airflow Rate Modulates Toxicant Profiles and Can Lead to Concerning Levels of Solvent Consumption.

ACS Omega 2018 Jan 2;3(1):30-36. Epub 2018 Jan 2.

Department of Chemistry, Portland State University, 1719 SW 10th Avenue, Portland, Oregon 97201, United States.

Electronic cigarettes enabling enhanced airflow have grown in popularity in recent years. The objective of this study is to show that flow rates modulate the levels of specific aerosol toxicants produced in electronic cigarettes. Flow rates used in various laboratory investigations involving e-cigarettes have varied widely to date, and can thus promote interlaboratory variability in aerosol product profiles. The thermal decomposition of hydroxyacetone and glycolaldehyde is less favorable at lower temperatures, supporting the observations of these products at higher flow rates/lower heating coil temperatures. Higher temperatures promote the formation of acetaldehyde from hydroxyacetone and formaldehyde from both hydroxyacetone and glycolaldehyde. A separate finding is that greater airflow can also expose users to concerning levels of e-liquid solvents. Under the modest conditions studied, propylene glycol aerosol levels are found at above the acceptable inhalation levels defined by NASA, and in range of the generally recognized as safe levels for daily ingestion.
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http://dx.doi.org/10.1021/acsomega.7b01521DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5793035PMC
January 2018

Effect of maternal glycemia and weight status on offspring birth measures and BMI-z among Chinese population in the first year.

Sci Rep 2017 11 22;7(1):16030. Epub 2017 Nov 22.

Department of Maternal and Child Health Care, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Hangkong Rd., Wuhan, 430030, Hubei, China.

To investigate the effects of maternal fasting plasma glucose (FPG) and pre-pregnancy weight status (PPWS) on offspring birth measures and body mass index z-score (BMI-z) in the first year, we conducted a prospective study of 1,096 mother-infant dyads in Guangdong, China, 2014-2015. Multivariate logistic regression was used to test independent/interaction associations of maternal FPG and PPWS with macrosomia/large for gestational age (LGA). Association of PPWS and FPG with offspring BMI-z in the first year was assessed by the linear mixed effects models. For each 1-mmol/L increase in FPG, the risk of macrosomia and LGA was elevated by 2.74 and 2.01 (95% CI: 1.85, 7.60 and 1.54, 5.88), respectively. No main effect of PPWS or interaction association of FPG and PPWS on macrosomia/LGA was observed (P > 0.05). A relation between maternal FPG and PPWS was detected (P < 0.05). Infants of Q5 FPG mothers, those who were born to OWO mothers, had a 0.35 increase in the BMI-z (95% CI: 0.16, 0.55) compared with infants of NW mothers. In conclusion, maternal FPG is positively associated with macrosomia/LGA. Maternal PPWS and FPG considerably interacted for the association with the risk of offspring high BMI-z in the first year.
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http://dx.doi.org/10.1038/s41598-017-15932-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5700092PMC
November 2017

Graphene Distributed Amplifiers: Generating Desirable Gain for Graphene Field-Effect Transistors.

Sci Rep 2015 Dec 4;5:17649. Epub 2015 Dec 4.

Institute of Microelectronics, Tsinghua University, Beijing, 100084, China.

Ever since its discovery, graphene bears great expectations in high frequency electronics due to its irreplaceably high carrier mobility. However, it has long been blamed for the weakness in generating gains, which seriously limits its pace of development. Distributed amplification, on the other hand, has successfully been used in conventional semiconductors to increase the amplifiers' gain-bandwidth product. In this paper, distributed amplification is first applied to graphene. Transmission lines phase-synchronize paralleled graphene field-effect transistors (GFETs), combining the gain of each stage in an additive manner. Simulations were based on fabricated GFETs whose fT ranged from 8.5 GHz to 10.5 GHz and fmax from 12 GHz to 14 GHz. A simulated four-stage graphene distributed amplifier achieved up to 4 dB gain and 3.5 GHz bandwidth, which could be realized with future IC processes. A PCB level graphene distributed amplifier was fabricated as a proof of circuit concept.
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http://dx.doi.org/10.1038/srep17649DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4669444PMC
December 2015
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