Publications by authors named "Zhili Chen"

33 Publications

Cardiac Dysfunction in a Mouse Vascular Dementia Model of Bilateral Common Carotid Artery Stenosis.

Front Cardiovasc Med 2021 11;8:681572. Epub 2021 Jun 11.

Department of Neurology, Henry Ford Hospital, Detroit, MI, United States.

Cardiac function is associated with cognitive function. Previously, we found that stroke and traumatic brain injury evoke cardiac dysfunction in mice. In this study, we investigate whether bilateral common carotid artery stenosis (BCAS), a model that induces vascular dementia (VaD) in mice, induces cardiac dysfunction. Late-adult (6-8 months) C57BL/6J mice were subjected to sham surgery ( = 6) or BCAS ( = 8). BCAS was performed by applying microcoils (0.16 mm internal diameter) around both common carotid arteries. Cerebral blood flow and cognitive function tests were performed 21-28 days post-BCAS. Echocardiography was conducted in conscious mice 29 days after BCAS. Mice were sacrificed 30 days after BCAS. Heart tissues were isolated for immunohistochemical evaluation and real-time PCR assay. Compared to sham mice, BCAS in mice significantly induced cerebral hypoperfusion and cognitive dysfunction, increased cardiac hypertrophy, as indicated by the increased heart weight and the ratio of heart weight/body weight, and induced cardiac dysfunction and left ventricular (LV) enlargement, indicated by a decreased LV ejection fraction (LVEF) and LV fractional shortening (LVFS), increased LV dimension (LVD), and increased LV mass. Cognitive deficits significantly correlated with cardiac deficits. BCAS mice also exhibited significantly increased cardiac fibrosis, increased oxidative stress, as indicated by 4-hydroxynonenal and NADPH oxidase-2, increased leukocyte and macrophage infiltration into the heart, and increased cardiac interleukin-6 and thrombin gene expression. BCAS in mice without primary cardiac disease provokes cardiac dysfunction, which, in part, may be mediated by increased inflammation and oxidative stress.
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http://dx.doi.org/10.3389/fcvm.2021.681572DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8225957PMC
June 2021

Deficiency of Endothelial Nitric Oxide Synthase (eNOS) Exacerbates Brain Damage and Cognitive Deficit in A Mouse Model of Vascular Dementia.

Aging Dis 2021 Jun 1;12(3):732-746. Epub 2021 Jun 1.

1Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA.

Vascular Dementia (VaD) accounts for nearly 20% of all cases of dementia. eNOS plays an important role in neurovascular remodeling, anti-inflammation, and cognitive functional recovery after stroke. In this study, we investigated whether eNOS regulates brain damage, cognitive function in mouse model of bilateral common carotid artery stenosis (BCAS) induced VaD. Late-adult (6-8 months) C57BL/6J and eNOS knockout (eNOS-/-) mice were subjected to BCAS (n=12/group) or sham group (n=8/group). BCAS was performed by applying microcoils to both common carotid arteries. Cerebral blood flow (CBF) and blood pressure were measured. A battery of cognitive functional tests was performed, and mice were sacrificed 30 days after BCAS. Compared to corresponding sham mice, BCAS in wild-type (WT) and eNOS-/- mice significantly: 1) induces short term, long term memory loss, spatial learning and memory deficits; 2) decreases CBF, increases ischemic cell damage, including apoptosis, white matter (WM) and axonal damage; 3) increases blood brain barrier (BBB) leakage, decreases aquaporin-4 (AQP4) expression and vessel density; 4) increases microglial, astrocyte activation and oxidative stress in the brain; 5) increases inflammatory factor interleukin-1 receptor-associated kinase-1(IRAK-1) and amyloid beta (Aβ) expression in brain; 6) increases IL-6 and IRAK4 expression in brain. eNOS-/-sham mice exhibit increased blood pressure, decreased iNOS and nNOS in brain compared to WT-sham mice. Compared to WT-BCAS mice, eNOS-/-BCAS mice exhibit worse vascular and WM/axonal damage, increased BBB leakage and inflammatory response, increased cognitive deficit, decreased iNOS, nNOS in brain. eNOS deficit exacerbates BCAS induced brain damage and cognitive deficit.
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http://dx.doi.org/10.14336/AD.2020.0523DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139201PMC
June 2021

Exosomes derived from bone marrow mesenchymal stem cells harvested from type two diabetes rats promotes neurorestorative effects after stroke in type two diabetes rats.

Exp Neurol 2020 12 2;334:113456. Epub 2020 Sep 2.

Neurology Research, Henry Ford Hospital, Detroit, MI 48202, USA. Electronic address:

Background And Purpose: Diabetes elevates the risk of stroke, promotes inflammation, and exacerbates vascular and white matter damage post stroke, thereby hindering long term functional recovery. Here, we investigated the neurorestorative effects and the underlying therapeutic mechanisms of treatment of stroke in type 2 diabetic rats (T2DM) using exosomes harvested from bone marrow stromal cells obtained from T2DM rats (T2DM-MSC-Exo).

Methods: T2DM was induced in adult male Wistar rats using a combination of high fat diet and Streptozotocin. Rats were subjected to transient 2 h middle cerebral artery occlusion (MCAo) and 3 days later randomized to one of the following treatment groups: 1) phosphate-buffered-saline (PBS, i.v), 2) T2DM-MSC-Exo, (3 × 10, i.v), 3) T2DM-MSC-Exo with miR-9 over expression (miR9+/+-T2DM-MSC-Exo, 3 × 10, i.v) or 4) MSC-Exo derived from normoglycemic rats (Nor-MSC-Exo) (3 × 10, i.v). T2DM sham control group is included as reference. Rats were sacrificed 28 days after MCAo.

Results: T2DM-MSC-Exo treatment does not alter blood glucose, lipid levels, or lesion volume, but significantly improves neurological function and attenuates post-stroke weight loss compared to PBS treated as well as Nor-MSC-Exo treated T2DM-stroke rats. Compared to PBS treatment, T2DM-MSC-Exo treatment of T2DM-stroke rats significantly 1) increases tight junction protein ZO-1 and improves blood brain barrier (BBB) integrity; 2) promotes white matter remodeling indicated by increased axon and myelin density, and increases oligodendrocytes and oligodendrocyte progenitor cell numbers in the ischemic border zone as well as increases primary cortical neuronal axonal outgrowth; 3) decreases activated microglia, M1 macrophages, and inflammatory factors MMP-9 (matrix mettaloproteinase-9) and MCP-1 (monocyte chemoattractant protein-1) expression in the ischemic brain; and 4) decreases miR-9 expression in serum, and increases miR-9 target ABCA1 (ATP-binding cassette transporter 1) and IGFR1 (Insulin-like growth factor 1 receptor) expression in the brain. MiR9+/+-T2DM-MSC-Exo treatment significantly increases serum miR-9 expression compared to PBS treated and T2DM-MSC-Exo treated T2DM stroke rats. Treatment of T2DM stroke with miR9+/+-T2DM-MSC-Exo fails to improve functional outcome and attenuates T2DM-MSC-Exo treatment induced white matter remodeling and anti-inflammatory effects in T2DM stroke rats.

Conclusions: T2DM-MSC-Exo treatment for stroke in T2DM rats promotes neurorestorative effects and improves functional outcome. Down regulation of miR-9 expression and increasing its target ABCA1 pathway may contribute partially to T2DM-MSC-Exo treatment induced white matter remodeling and anti-inflammatory responses.
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http://dx.doi.org/10.1016/j.expneurol.2020.113456DOI Listing
December 2020

Economic burden of IADPSG gestational diabetes diagnostic criteria in China: propensity score matching analysis from a 7-year retrospective cohort.

BMJ Open Diabetes Res Care 2020 08;8(1)

Department of Public Health and Preventive Medicine, School of Medicine, Jinan University, Guangzhou, China

Introduction: The International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria for gestational diabetes mellitus (GDM) increased the morbidity significantly, but the cost and effectiveness of its application are still unclear. This study aimed to analyze the impact of the IADPSG criteria for diagnosing GDM in China on the perinatal outcomes, and medical expenditure of GDM women versus those with normal glucose tolerance (NGT).

Research Design And Methods: We conducted a retrospective cohort study involving 7794 women admitted at the First Affiliated Hospital of Jinan University (Guangzhou, China), from November 1, 2010 to October 31, 2017. The perinatal outcomes and medical expenditure were retrieved from the electronic medical records in the hospital. Propensity score matching (PSM, in a 1:1 ratio) algorithm was used to minimize confounding effects on the difference in the two cohorts.

Results: PSM minimized the difference of baseline characteristics between women with and without GDM. Of 7794 pregnant women, half (n=3897) were all of the pregnant women with GDM admitted to the hospital during the period, the other half women had NGT and were selected randomly to match with their counterparts. Adopting the IADPSG criteria was associated with reduced risk of emergency cesarean section, polyhydramnios, turbid amniotic fluid and perineal injury (p0.01 for all) and having any one of the adverse fetal outcomes (p0.01), including fetal distress, umbilical cord around the neck, neonatal encephalopathy, admission to neonatal intensive care unit, birth trauma, neonatal hypoglycemia and fetal death. After PSM, the median total medical expenditure by the GDM women was ¥912.9 (US$140.7 in 2015) more than that of the the NGT women (p0.09).

Conclusions: Despite the increasing medical expenditure, screening at 24-28 gestational weeks under the IADPSG guidelines with the 2-hour, 75 g oral glucose tolerance test can improve short-term maternal and neonatal outcomes.
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http://dx.doi.org/10.1136/bmjdrc-2020-001538DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7451487PMC
August 2020

SUMO1 Deficiency Exacerbates Neurological and Cardiac Dysfunction after Intracerebral Hemorrhage in Aged Mice.

Transl Stroke Res 2021 08 6;12(4):631-642. Epub 2020 Aug 6.

Department of Neurology, Henry Ford Hospital, Detroit, MI-48202, USA.

Small ubiquitin-like modifier 1 (SUMO1) reduces cardiac hypertrophy and induces neuroprotective effects. Previous studies have found that intracerebral hemorrhage (ICH) provokes cardiac deficit in the absence of primary cardiac diseases in mice. In this study, we tested the hypothesis that SUMO1 deficiency leads to worse brain and heart dysfunction after ICH and SUMO1 plays a key role in regulating brain-heart interaction after ICH in aged mice. Aged (18-20 months) female SUMO1 null (SUMO1) mice and wild-type (WT) C57BL/6 J mice were randomly divided into four groups (n = 8/group): (1) WT-sham group, (2) SUMO1-sham group, (3) WT-ICH group, and (4) SUMO1-ICH group. Cardiac function was measured by echocardiography. Neurological and cognitive functional tests were performed. Mice were sacrificed at 10 days after ICH for histological and immunohistochemically staining. Compared with WT-sham mice, WT-ICH mice exhibited (1) significantly (P < 0.05) decreased SUMO1 expression in heart tissue, (2) evident neurological and cognitive dysfunction as well as brain white matter deficits, (3) significantly increased cardiac dysfunction, and (4) inflammatory factor expression in the heart and brain. Compared with WT-ICH mice, SUMO1-ICH mice exhibited significantly increased: (1) brain hemorrhage volume, worse neurological and cognitive deficits, and increased white matter deficits; (2) cardiac dysfunction and cardiac fibrosis; (3) inflammatory response both in heart and brain tissue. Aged SUMO1-deficient female mice subjected to ICH not only exhibit increased neurological and cognitive functional deficit but also significantly increased cardiac dysfunction and inflammatory cell infiltration into the heart and brain. These data suggest that SUMO1 plays an important role in brain-heart interaction.
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http://dx.doi.org/10.1007/s12975-020-00837-6DOI Listing
August 2021

Disturbance mechanisms of lacustrine organic carbon burial: Case study of Cuopu Lake, Southwest China.

Sci Total Environ 2020 Dec 9;746:140615. Epub 2020 Jul 9.

School of Geography Science, Nanjing Normal University, Nanjing 210023, PR China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023, PR China; Key Laboratory of Virtual Geographic Environment (Nanjing Normal University), Ministry of Education, Nanjing 210023, PR China; State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province), Nanjing 210023, PR China. Electronic address:

Lakes are important organic carbon (OC) traps in the global carbon cycle. Recent studies have shown that the rate of OC burial in lacustrine sediments is influenced by factors such as climate change, land-use change, and eutrophication. In this study, we use multiproxy methods to reveal the mechanisms of lacustrine sediment OC burial in an alpine lake (Cuopu Lake), in southwest China. Combined with the dating from Pb and n-alkanes distribution analysis using the Positive Matrix Factorization model, the sedimentary history was divided into five stages: religious activity (the 1840s-1880s), earthquake (the 1880s-1910s), garrison (the 1910s-1960s), transition (the 1960s-1990s), and ecotourism (the 1990s-2010s). During the earthquake stage, OC burial was dominated by terrestrial solids (>40%) and co-precipitated algae (>30%), with a rapid deposition rate (>4 mm a) and low OC concentration (<4 mg g). During the other stages, when the level of disturbance was relatively low, a change in nutrient conditions either promoted or inhibited plant growth, which influenced the type of buried OC. The contribution of OC derived from combustion sources varied from stage to stage. Severe anthropogenic disturbances have led to a significant increase in nutritional levels in the lake water, leading to an increase in the OC burial rate. Climate change, which leads to changes in temperature and rainfall, did not significantly influence OC burial, whereas nitrogen deposition (and associated ecological changes) was a significant determinant. When the general mechanism is dominant, the total nitrogen to inorganic phosphorus ratio is an effective indicator of OC burial due to its selective promotion of different plant types. In conclusion, our results suggest that lacustrine sediment OC burial is closely linked to physical and anthropogenic factors in Cuopu Lake, as well as similar montane lakes.
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http://dx.doi.org/10.1016/j.scitotenv.2020.140615DOI Listing
December 2020

Netrin-1 reduces lung ischemia-reperfusion injury by increasing the proportion of regulatory T cells.

J Int Med Res 2020 Jun;48(6):300060520926415

Department of Critical Care Medicine, Wenzhou Central Hospital, Wenzhou, China.

Objective: Inflammation is the primary mechanism of lung ischemia-reperfusion injury (LIRI) and neurologic factors can regulate inflammatory immune responses. Netrin-1 is an axonal guidance molecule, but whether Netrin-1 plays a role in LIRI remains unclear.

Methods: A mouse model of LIRI was established. Immunohistochemistry was used to detect expression of Netrin-1 and to enumerate macrophages and T cells in lung tissue. The proportion of regulatory T cells (Tregs) was assessed by flow cytometry. Levels of apoptosis were assessed by terminal deoxynucleotidyl transferase dUTP nick end staining.

Results: Numbers of macrophages and T cells in the lung tissues of mice with LIRI were elevated, while expression of netrin-1 was significantly decreased. Flow cytometry showed that the proportion of Tregs in mice with LIRI was significantly decreased. The proportion of Tregs among lymphocytes was positively correlated with netrin-1 expression. experiments showed that netrin-1 promoted an increase in Treg proportion through the A2b receptor. Animal experiments showed that netrin-1 could inhibit apoptosis and reduce T cell and macrophage infiltration by increasing the proportion of Tregs, ultimately reducing LIRI. Treg depletion using an anti-CD25 monoclonal antibody blocked the effects of netrin-1.

Conclusion: Netrin-1 reduced LIRI by increasing the proportion of Tregs.
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http://dx.doi.org/10.1177/0300060520926415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271279PMC
June 2020

-Iodosuccinimide-Mediated Dimerization of 2-Alkynylnaphthols: A Highly Diastereoselective Construction of Bridged Polycyclic Compounds via Vinylidene -Quinone Methide Intermediate.

Org Lett 2020 Jun 11;22(11):4461-4466. Epub 2020 May 11.

Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P.R. China.

An unprecedented highly diastereoselective dimerization of 2-alkynylnaphthols is presented to furnish bridged polycyclic compounds containing a bicyclo[3.2.1]octane moiety with good to excellent yields. The reaction proceeded under mild conditions using -iodosuccinimide as a promoter, simultaneously constructing one new C-O bond and two new C-C bonds. A tetra-substituted vinylidene -quinone methide intermediate was likely involved, and the steric hindrance of substituents played a critical role in this transformation.
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http://dx.doi.org/10.1021/acs.orglett.0c01458DOI Listing
June 2020

CD133+Exosome Treatment Improves Cardiac Function after Stroke in Type 2 Diabetic Mice.

Transl Stroke Res 2021 02 20;12(1):112-124. Epub 2020 Mar 20.

Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA.

Cardiac complications post-stroke are common, and diabetes exacerbates post-stroke cardiac injury. In this study, we tested whether treatment with exosomes harvested from human umbilical cord blood derived CD133+ cells (CD133+Exo) improves cardiac function in type 2 diabetes mellitus (T2DM) stroke mice. Adult (3-4 m), male, BKS.Cg-m+/+Lepr/J (db/db, T2DM) and non-DM (db+) mice were randomized to sham or photothrombotic stroke groups. T2DM-stroke mice were treated with phosphate-buffered saline (PBS) or CD133+Exo (20 μg, i.v.) at 3 days after stroke. T2DM sham and T2DM+CD133+Exo treatment groups were included as controls. Echocardiography was performed, and mice were sacrificed at 28 days after stroke. Cardiomyocyte hypertrophy, myocardial capillary density, interstitial fibrosis, and inflammatory factor expression were measured in the heart. MicroRNA-126 expression and its target gene expression were measured in the heart. T2DM mice exhibit significant cardiac deficits such as decreased left ventricular ejection fraction (LVEF) and shortening fraction (LVSF), increased left ventricular diastolic dimension (LVDD), and reduced heart rate compared to non-DM mice. Stroke in non-DM and T2DM mice significantly decreases LVEF compared to non-DM and T2DM-sham, respectively. Cardiac dysfunction is worse in T2DM-stroke mice compared to non-DM-stroke mice. CD133+Exo treatment of T2DM-stroke mice significantly improves cardiac function identified by increased LVEF and decreased LVDD compared to PBS treated T2DM-stroke mice. In addition, CD133+Exo treatment significantly decreases body weight and blood glucose but does not decrease lesion volume in T2DM-stroke mice. CD133+Exo treatment of T2DM mice significantly decreases body weight and blood glucose but does not improve cardiac function. CD133+Exo treatment in T2DM-stroke mice significantly decreases myocardial cross-sectional area, interstitial fibrosis, transforming growth factor beta (TGF-β), numbers of M1 macrophages, and oxidative stress markers 4-HNE (4-hydroxynonenal) and NADPH oxidase 2 (NOX2) in heart tissue. CD133+Exo treatment increases myocardial capillary density in T2DM-stroke mice as well as upregulates endothelial cell capillary tube formation in vitro. MiR-126 is highly expressed in CD133+Exo compared to exosomes derived from endothelial cells. Compared to PBS treatment, CD133+Exo treatment significantly increases miR-126 expression in the heart and decreases its target gene expression such as Sprouty-related, EVH1 domain-containing protein 1 (Spred-1), vascular cell adhesion protein (VCAM), and monocyte chemoattractant protein 1 (MCP1) in the heart of T2DM-stroke mice. CD133+Exo treatment significantly improves cardiac function in T2DM-stroke mice. The cardio-protective effects of CD133+Exo in T2DM-stroke mice may be attributed at least in part to increasing miR-126 expression and decreasing its target protein expression in the heart, increased myocardial capillary density and decreased cardiac inflammatory factor expression.
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http://dx.doi.org/10.1007/s12975-020-00807-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7502550PMC
February 2021

Organocatalytic Enantioselective γ-Elimination: Applications in the Preparation of Chiral Peroxides and Epoxides.

Org Lett 2020 03 14;22(5):1934-1940. Epub 2020 Feb 14.

Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P. R. China.

An organocatalyzed enantioselective γ-elimination process has been achieved and applied in the kinetic resolution of peroxides to access chiral peroxides and epoxides. The reaction provided a pathway for the preparation of two useful synthetic and biologically important structural motifs through a single-step reaction. A range of substrates has been resolved with a selectivity factor up to 63. The obtained enantioenriched peroxides and epoxides allowed a series of transformations with retained optical purities.
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http://dx.doi.org/10.1021/acs.orglett.0c00295DOI Listing
March 2020

Brain-Derived Microparticles (BDMPs) Contribute to Neuroinflammation and Lactadherin Reduces BDMP Induced Neuroinflammation and Improves Outcome After Stroke.

Front Immunol 2019 26;10:2747. Epub 2019 Nov 26.

Department of Neurology, Henry Ford Hospital, Detroit, MI, United States.

Microparticles (MPs, ~size between 0.1 and 1 mm) are lipid encased containers derived from intact cells which contain antigen from the parent cells. MPs are involved in intercellular communication and regulate inflammation. Stroke increases secretion of brain derived MP (BDMP) which activate macrophages/microglia and induce neuroinflammation. Lactadherin (Milk fat globule-EGF factor-8) binds to anionic phospholipids and extracellular matrices, promotes apoptotic cell clearance and limits pathogenic antigen cross presentation. In this study, we investigate whether BDMP affects stroke-induced neuroinflammation and whether Lactadherin treatment reduces stroke initiated BDMP-induced neuroinflammation, thereby improving functional outcome after stroke. Middle aged (8-9 months old) male C57BL/6J mice were subjected to distal middle cerebral artery occlusion (dMCAo) stroke, and BDMPs were extracted from ischemic brain 24 h after dMCAo by ultracentrifugation. Adult male C57BL/6J mice were subjected to dMCAo and treated via tail vein injection at 3 h after stroke with: (A) +PBS ( = 5/group); (B) +BDMPs (1.5 × 10, = 6/group); (C) +Lactadherin (400 μg/kg, = 5/group); (D) ++Lactadherin ( = 6/group). A battery of neurological function tests were performed and mice sacrificed for immunostaining at 14 days after stroke. Blood plasma was used for Western blot assay. Our data indicate: (1) treatment of Stroke with BDMP significantly increases lesion volume, neurological deficits, blood brain barrier (BBB) leakage, microglial activation, inflammatory cell infiltration (CD45, microglia/macrophages, and neutrophils) into brain, inflammatory factor (TNFα, IL6, and IL1β) expression in brain, increases axon/white matter (WM) damage identified by decreased axon and myelin density, and increases inflammatory factor expression in the plasma when compared to PBS treated stroke mice; (2) when compared to PBS and BDMP treated stroke mice, Lactadherin and BDMP+Lactadherin treatment significantly improves neurological outcome, and decreases lesion volume, BBB leakage, axon/WM injury, inflammatory cell infiltration and inflammatory factor expression in the ischemic brain, respectively. Lactadherin treatment significantly increases anti-inflammatory factor (IL10) expression in ischemic brain and decreases IL1β expression in plasma compared to PBS and BDMP treated stroke mice, respectively. BDMP increases neuroinflammation and aggravates ischemic brain damage after stroke. Thus, Lactadherin exerts anti-inflammatory effects and improves the clearance of MPs to reduce stroke and BDMP induced neurological deficits.
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http://dx.doi.org/10.3389/fimmu.2019.02747DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6968774PMC
November 2020

Spleen associated immune-response mediates brain-heart interaction after intracerebral hemorrhage.

Exp Neurol 2020 05 24;327:113209. Epub 2020 Jan 24.

Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA. Electronic address:

Background And Purpose: Intracerebral hemorrhage (ICH) patients frequently encounter cardiovascular complications which may contribute to increased mortality and poor long term outcome. ICH induces systemic oxidative stress and activates peripheral immune responses which are involved in the pathological cascade leading to cardiac dysfunction and heart failure after ICH. We have previously reported that ICH induces progressive cardiac dysfunction in mice without primary cardiac diseases. In this study, we have investigated the role of immune response in mediating cardiac dysfunction post ICH in mice.

Methods: Adult male C57BL/6 J mice were randomly assigned to the following groups (n = 8/group): 1) sham control; 2) ICH; 3) splenectomy with ICH (ICH + Spx); 4) splenectomy alone (Spx). Echocardiography was performed at 7 and 28 days after ICH. A battery of neurological and cognitive tests were performed. Flow cytometry, western blot and immunostaining were used to test mechanisms of ICH induced cardiac dysfunction.

Results: Compared to sham control mice, Spx alone does not induce acute (7 day) or chronic (28 day) cardiac dysfunction. ICH induces significant neurological and cognitive deficits, as well as acute and chronic cardiac dysfunction compared to sham control mice. Mice subjected to ICH + Spx exhibit significantly improved neurological and cognitive function compared to ICH mice. Mice with ICH + Spx also exhibit significantly improved acute and chronic cardiac function compared to ICH mice indicated by increased left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS), decreased cardiac fibrosis, decreased cardiomyocyte hypertrophy, decreased cardiac infiltration of immune cells and decreased expression of inflammatory factor and oxidative stress in the heart.

Conclusions: Our study demonstrates that splenectomy attenuates ICH-induced neurological and cognitive impairment as well as ICH-induced cardiac dysfunction in mice. Inflammatory cell infiltration into heart and immune responses mediated by the spleen may contribute to ICH-induce acute and chronic cardiac dysfunction and pathological cardiac remodeling.
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http://dx.doi.org/10.1016/j.expneurol.2020.113209DOI Listing
May 2020

Speckle Reduction in Optical Coherence Tomography via Super-Resolution Reconstruction.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:5589-5592

Reducing speckle noise from the optical coherence tomograms (OCT) of human retina is a fundamental step to a better visualization and analysis in retinal imaging, as thus to support examination, diagnosis and treatment of many eye diseases. In this study, we propose a new method for speckle reduction in OCT images using the super-resolution technology. It merges multiple images for the same scene but with sub-pixel movements and restores the missing signals in one pixel, which significantly improves the image quality. The proposed method is evaluated on a dataset of 20 OCT volumes (5120 images), through the mean square error, peak signal to noise ratio and the mean structure similarity index using high quality line-scan images as reference. The experimental results show that the proposed method outperforms existing state-of-the-art approaches in applicability, effectiveness, and accuracy.
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http://dx.doi.org/10.1109/EMBC.2019.8856445DOI Listing
July 2019

Automated Iris Segmentation from Anterior Segment OCT Images with Occludable Angles via Local Phase Tensor.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:4745-4749

Morphological changes in the iris are one of the major causes of angle-closure glaucoma, and an anteriorly-bowed iris may be further associated with greater risk of disease progression from primary angle-closure suspect (PACS) to chronic primary angle-closure glaucoma (CPCAG). In consequence, the automated detection of abnormalities in the iris region is of great importance in the management of glaucoma. In this paper, we present a new method for the extraction of the iris region by using a local phase tensor-based curvilinear structure enhancement method, and apply it to anterior segment optical coherence tomography (AS-OCT) imagery in the presence of occludable iridocorneal angle. The proposed method is evaluated across a dataset of 200 anterior chamber angle (ACA) images, and the experimental results show that the proposed method outperforms existing state-of-the-art method in applicability, effectiveness, and accuracy.
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http://dx.doi.org/10.1109/EMBC.2019.8857336DOI Listing
July 2019

Multiscale connected chain topological modelling for microcalcification classification.

Comput Biol Med 2019 11 5;114:103422. Epub 2019 Sep 5.

Department of Computer Science, Aberystwyth University, SY23 3DB, UK.

Computer-aided diagnosis (CAD) systems can be employed to help classify mammographic microcalcification clusters. In this paper, a novel method for the classification of the microcalcification clusters based on topology/connectivity has been introduced. The proposed method is distinct from existing techniques which concentrate on morphology and texture of microcalcifications and surrounding tissue. The proposed approach used multiscale morphological relationship of connectivity between microcalcifications where connected chains between nearest microcalcifications were generated at each scale. Subsequently, graph connectivity features at each scale were extracted to estimate the topological connectivity structure of microcalcification clusters for benign versus malignant classification. The proposed approach was evaluated using publicly available digitized datasets: MIAS and DDSM, in addition to the digital OPTIMAM dataset. The classification of features using KNN obtained a classification accuracy of 86.47±1.30%, 90.0±0.00%, 82.5±2.63%, 76.75±0.66% for the DDSM, MIAS-manual, MIAS-auto and OPTIMAM datasets respectively. The study showed that topological/connectivity modelling using a multiscale approach was appropriate for microcalcification cluster analysis and classification; topological connectivity and distribution can be linked to clinical understanding of microcalcification spatial distribution.
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http://dx.doi.org/10.1016/j.compbiomed.2019.103422DOI Listing
November 2019

Organocatalytic Enantioselective Selenosulfonylation of a C-C Double Bond To Form Two Stereogenic Centers in an Aqueous Medium.

J Org Chem 2019 Jun 4;84(12):8100-8111. Epub 2019 Jun 4.

Pharmaceutical and Material Engineering School , Jinhua Polytechnic , Jinhua , Zhejiang Province 321000 , P. R. China.

Organocatalytic selenosulfonylation of the C-C double bond of α,β-unsaturated ketones to construct two contiguous stereogenic centers in an aqueous medium was described. A series of α-selenyl and β-sulfonyl ketones with various functional groups were synthesized in good yields and enantioselectivities with saturated NaCl solution as the solvent. In addition, this protocol had been successfully scaled up to a decagram scale via a simple workup procedure.
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http://dx.doi.org/10.1021/acs.joc.9b00973DOI Listing
June 2019

Histomorphological Comparisons and Expression Patterns of Gene in Sheep Testes at Different Development Stages.

Animals (Basel) 2019 Mar 21;9(3). Epub 2019 Mar 21.

College of Animal Science and Technology, Gansu Agricultural University, Lanzhou 730070, China.

is implicated in mammalian testicular function maintenance and spermatogenesis. To understand the expression patterns and biological functions of sheep , we examined the expression and immunolocalization of BOLL in the developing testes of Small-Tail Han sheep aged 0 days (D0), 2 months (2M), 5 months (5M), 1 year (1Y), and 2 years (2Y), by qPCR, Western blot, and immunohistochemistry methods. Firstly, morphological studies revealed that, in addition to spermatogonia, ordered and clear spermatocytes, as well as round and elongated spermatids and sperm, were found in the 1Y and 2Y testicular seminiferous tubules of the sheep testes, compared with the D0, 2M, and 5M testes, as analyzed by hematoxylin and eosin (H&E) staining. The diameter and area of the seminiferous tubules, epithelial thickness, and the area and perimeter of the tubule lumens gradually increased with age. was specifically expressed in testes and upregulation of transcript expression was higher in the testes of the 1Y and 2Y groups than in those of the D0, 2M, and 5M groups. Similarly, BOLL protein was expressed mainly in the 1Y and 2Y testes, ranging from primary spermatocytes to round spermatids, as well as in the spermatozoa. This study is the first demonstration that sheep might serve as a key regulator of the spermiogenesis involved in sperm maturity, in addition to its role as a crucial meiotic regulator.
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http://dx.doi.org/10.3390/ani9030105DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6466207PMC
March 2019

Motion parallax for 360° RGBD video.

IEEE Trans Vis Comput Graph 2019 May 6;25(5):1817-1827. Epub 2019 Mar 6.

We present a method for adding parallax and real-time playback of 360° videos in Virtual Reality headsets. In current video players, the playback does not respond to translational head movement, which reduces the feeling of immersion, and causes motion sickness for some viewers. Given a 360° video and its corresponding depth (provided by current stereo 360° stitching algorithms), a naive image-based rendering approach would use the depth to generate a 3D mesh around the viewer, then translate it appropriately as the viewer moves their head. However, this approach breaks at depth discontinuities, showing visible distortions, whereas cutting the mesh at such discontinuities leads to ragged silhouettes and holes at disocclusions. We address these issues by improving the given initial depth map to yield cleaner, more natural silhouettes. We rely on a three-layer scene representation, made up of a foreground layer and two static background layers, to handle disocclusions by propagating information from multiple frames for the first background layer, and then inpainting for the second one. Our system works with input from many of today's most popular 360° stereo capture devices (e.g., Yi Halo or GoPro Odyssey), and works well even if the original video does not provide depth information. Our user studies confirm that our method provides a more compelling viewing experience than without parallax, increasing immersion while reducing discomfort and nausea.
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http://dx.doi.org/10.1109/TVCG.2019.2898757DOI Listing
May 2019

Metal-free difunctionalization of alkynes to access tetrasubstituted olefins through spontaneous selenosulfonylation of vinylidene ortho-quinone methide (VQM).

Org Biomol Chem 2019 01;17(5):1121-1129

Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences, Chongqing University, Chongqing 401331, P. R. China.

A metal-free difunctionalization of alkynes to access tetrasubstituted olefins through spontaneous selenosulfonylation of vinylidene ortho-quinone methide (VQM) was described herein. The reaction was conducted under mild conditions without any catalysts or additives. Preliminary mechanism studies revealed that the formation of VQM was the key for this alkyne di-functionalization reaction. The reaction could be applied in the enantioselective asymmetric synthesis of axially chiral styrene. Furthermore, the selenosulfonylation adducts can be transformed into useful naphtho[2,1-b]furan and benzofuran scaffolds.
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http://dx.doi.org/10.1039/c8ob02967aDOI Listing
January 2019

Sildenafil treatment of vascular dementia in aged rats.

Neurochem Int 2019 07 25;127:103-112. Epub 2018 Dec 25.

Department of Neurology, Henry Ford Hospital, Detroit, MI, 48202, USA. Electronic address:

Background: and purpose: In this study, we employed a multiple microinfarction (MMI) based vascular dementia (VaD) model in aged rats and tested the therapeutic effects of Sildenafil, a phosphodiesterase type 5 inhibitor, on cognitive decline, white matter damage, autophagy and inflammatory response associated with VaD.

Methods: Male, aged (16-18 months) Wistar rats were subjected to MMI (800 ± 100, 70-100 μm cholesterol crystals injected into the internal carotid artery) and treated with or without Sildenafil (2 mg/kg, i.p) starting at 24 h after MMI daily for 28 days. Four experimental groups were employed: Sham control, Sham + Sildenafil, MMI, and MMI + Sildenafil. A battery of cognitive tests were performed and rats were sacrificed at 28 days after MMI for immunohistochemical evaluation and PCR assay.

Results: Sildenafil treatment in aged MMI rats significantly improves short term memory evaluated by the novel object recognition test and improves spatial learning and memory in the Morris water maze test compared to aged control MMI rats. Sildenafil treatment of aged MMI rats significantly increases axon and myelin density in the corpus callosum and white matter bundles in the striatum, increases oligodendrocyte and oligodendrocyte progenitor cell number in the corpus callosum, cortex and striatum, and increases synaptic protein expression in the cortex and striatum compared to aged control MMI rats. In addition, Sildenafil treatment of MMI in aged rats significantly decreases Beclin1 expression and inflammatory factors Monocyte chemoattractant protein-1 and Interleukin-1β expression in brain. Sildenafil treatment in aged rats does not improve cognitive outcome compared to aged sham control rats.

Conclusions: Sildenafil treatment of MMI in aged rats significantly improves cognition and memory at 1 month after MMI. Sildenafil treatment increases axon and myelin density, increases Synaptophysin expression, decreases autophagic activity and exerts anti-inflammatory effects which in concert may contribute to cognitive improvement in aged rats subjected to MMI.
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http://dx.doi.org/10.1016/j.neuint.2018.12.015DOI Listing
July 2019

Intracerebral Hemorrhage Induces Cardiac Dysfunction in Mice Without Primary Cardiac Disease.

Front Neurol 2018 20;9:965. Epub 2018 Nov 20.

Department of Neurology, Henry Ford Hospital, Detroit, MI, United States.

Intracerebral hemorrhage (ICH) is a life threatening stroke subtype and a worldwide health problem. In this study, we investigate brain-heart interaction after ICH in mice and test whether ICH induces cardiac dysfunction in the absence of primary cardiac disease. We also investigate underlying mechanisms such as oxidative stress and inflammatory responses in mediating cardiac dysfunction post-ICH in mice. Male, adult (3-4 m) C57BL/6J mice were subjected to sham surgery or ICH using an autologous blood injection model ( = 16/group). Cardiac function was evaluated at 7 and 28 days after ICH using echocardiography ( = 8/group per time point). Western blot and immunostaining analysis were employed to assess oxidative stress and inflammatory responses in the heart. Mice subjected to ICH exhibited significantly decreased cardiac contractile function measured by left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) at 7 and 28 days after ICH compared to sham-control mice ( < 0.05). ICH induced cardiac dysfunction was significantly worse at 28 days than at 7 days after ICH ( < 0.05). ICH in mice significantly increased cardiomyocyte apoptosis, inflammatory factor expression and inflammatory cell infiltration in heart tissue, and induced cardiac oxidative stress at 7 days post-ICH compared to sham-control mice. Compared to sham-control mice, ICH-mice also exhibited significantly increased ( < 0.05) cardiomyocyte hypertrophy and cardiac fibrosis at 28 days after ICH. ICH induces significant and progressive cardiac dysfunction in mice. ICH increases cardiac oxidative stress and inflammatory factor expression in heart tissue which may play key roles in ICH-induced cardiac dysfunction.
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http://dx.doi.org/10.3389/fneur.2018.00965DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6256175PMC
November 2018

Inflammatory responses mediate brain-heart interaction after ischemic stroke in adult mice.

J Cereb Blood Flow Metab 2020 06 22;40(6):1213-1229. Epub 2018 Nov 22.

Neurology, Henry Ford Hospital, Detroit, MI, USA.

Stroke induces cardiac dysfunction which increases post stroke mortality and morbidity particularly in aging population. Here, we investigated the effects of inflammatory responses as underlying mediators of cardiac dysfunction after stroke in adult mice. Adult (eight-to-nine months) male C57BL/6 mice were subjected to photothrombotic stroke. To test whether immunoresponse to stroke leads to cardiac dysfunction, splenectomy was performed with stroke. Immunohistochemistry, flow cytometry, PCR, ELISA and echocardiography were performed. We found marginal cardiac dysfunction at acute phase and significant cardiac dysfunction at chronic phase of stroke as indicated by significant decrease of left ventricular ejection fraction (LVEF) and shortening fraction (LVSF). Stroke significantly increases macrophage infiltration into the heart and increases IL-1β, IL-6, MCP-1, TGF-β and macrophage-associated inflammatory cytokine levels in the heart as well as induces cardiac-fibrosis and hypertrophy. Splenectomy with stroke significantly reduces macrophage infiltration into heart, decreases inflammatory factor expression in the heart, decreases cardiac hypertrophy and fibrosis, as well as significantly improves cardiac function compared to non-splenectomized adult stroke mice. Therefore, cerebral ischemic stroke in adult mice induces chronic cardiac dysfunction and secondary immune response may contribute to post stroke cardiac dysfunction.
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http://dx.doi.org/10.1177/0271678X18813317DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7238382PMC
June 2020

Organocatalytic Enantioselective Construction of Axially Chiral Sulfone-Containing Styrenes.

J Am Chem Soc 2018 06 31;140(23):7056-7060. Epub 2018 May 31.

Chongqing Key Laboratory of Natural Product Synthesis and Drug Research, School of Pharmaceutical Sciences , Chongqing University , Chongqing 401331 , P. R. China.

We describe herein an organocatalytic enantioselective approach for the construction of axially chiral sulfone-containing styrenes. Various axially chiral sulfone-containing styrene compounds were prepared with excellent enantioselectivities (up to >99% ee) and almost complete E/ Z selectivities (>99% E/ Z). Furthermore, the axially chiral sulfone-containing styrenes could be easily converted into phosphonic acid and S/P ligands, which could be potentially used as organocatalysts or ligands in asymmetric catalysis.
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http://dx.doi.org/10.1021/jacs.8b03211DOI Listing
June 2018

Highly Efficient Trivalent Americium/Europium Separation by Phenanthroline-Derived Bis(pyrazole) Ligands.

Inorg Chem 2018 May 10;57(10):5782-5790. Epub 2018 May 10.

College of Chemistry , Sichuan University , Chengdu 610064 , P. R. China.

The synthesis, Eu complexation, and solvent extraction of Am and Eu from nitric acid solutions by tetradentate phenanthroline-derived bis(pyrazole) (BPPhen) ligands were described. By using meta-nitrobenzotrifluoride as diluent, BPPhen ligands in combination with 2-bromohexanoic acid extracted Am and Eu with remarkably high efficiency, excellent selectivity, and fast extraction kinetics. Stripping posed no issues. The ligands also showed excellent hydrolytic stability and acid tolerance. 2-Bromohexanoic anion neutralized the charge and increased the lipophilicity of the extracted ion pair. The extraction conformed to a cation exchange model. Slope analysis demonstrated the extraction of 1:2 metal/ligand complexes. Analyses by electrospray ionization mass spectrometry, time-resolved laser-induced fluorescence spectroscopy, Raman, and Fourier transform infrared techniques indicated that the composition of the extracted species is [Eu(nOct-BPPhen)(HO)]. The formation of 1:2 complexes was also confirmed by UV-vis spectroscopic titration and microcalorimetric titration methods. Meanwhile, the stability constants ( K) and the thermodynamic parameters (Δ H, Δ S, Δ G) for the complexation of Eu with nOct-BPPhen were presented too.
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http://dx.doi.org/10.1021/acs.inorgchem.8b00074DOI Listing
May 2018

Brain-Heart Interaction: Cardiac Complications After Stroke.

Circ Res 2017 Aug;121(4):451-468

From the Gerontology and Neurological Institute, Tianjin Medical University General Hospital, China (Z.C., T.Y., J.C.); Department of Neurology, Henry Ford Hospital, Detroit, MI (P.V., D.S., M.C., J.C.); and Department of Physics, Oakland University, Rochester, MI (M.C.).

Neurocardiology is an emerging specialty that addresses the interaction between the brain and the heart, that is, the effects of cardiac injury on the brain and the effects of brain injury on the heart. This review article focuses on cardiac dysfunction in the setting of stroke such as ischemic stroke, brain hemorrhage, and subarachnoid hemorrhage. The majority of post-stroke deaths are attributed to neurological damage, and cardiovascular complications are the second leading cause of post-stroke mortality. Accumulating clinical and experimental evidence suggests a causal relationship between brain damage and heart dysfunction. Thus, it is important to determine whether cardiac dysfunction is triggered by stroke, is an unrelated complication, or is the underlying cause of stroke. Stroke-induced cardiac damage may lead to fatality or potentially lifelong cardiac problems (such as heart failure), or to mild and recoverable damage such as neurogenic stress cardiomyopathy and Takotsubo cardiomyopathy. The role of location and lateralization of brain lesions after stroke in brain-heart interaction; clinical biomarkers and manifestations of cardiac complications; and underlying mechanisms of brain-heart interaction after stroke, such as the hypothalamic-pituitary-adrenal axis; catecholamine surge; sympathetic and parasympathetic regulation; microvesicles; microRNAs; gut microbiome, immunoresponse, and systemic inflammation, are discussed.
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http://dx.doi.org/10.1161/CIRCRESAHA.117.311170DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5553569PMC
August 2017

Chemical composition and biological activities of essential oil from Filifolium sibiricum (L.) Kitam.

Nat Prod Res 2016 Dec 2;30(24):2861-2863. Epub 2016 Jun 2.

a Key Laboratory of Chinese Materia Medica(Ministry of Education) , Heilongjiang University of Chinese Medicine , Harbin , China.

The essential oil from Filifolium sibiricum (L.) Kitam were extracted using hydrodistillation and GC-MS was used to analyse the essential oil. The main components were espatulenol (8.55%), geranyl acetate (8.03%), caryophyllene oxide (5.47%), calamenene (4.79%), geraniol (4.28%), calamenene (4.53%), geraniol (4.06%), cedrene epoxide (3.23%), myrtenol (3.18%), transgeranylgeranio (3.13%), etc. The essential oil showed intensive inhibitory effects against MCF-7 with IC level of 0.78 mg/mL, HepG-2 with IC level of 0.44 mg/mL, SKOV-3 with IC level of 0.27 mg/mL, BGC-823 with IC level of 0.34 mg/mL. In the antibacterial test, the essential oil showed the significant antibacterial activities. The MIC and MBC values were 5.20 and 5.20 mg/mL against Staphylococcus aureus.
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http://dx.doi.org/10.1080/14786419.2016.1188098DOI Listing
December 2016

Computer-aided diagnosis: detection and localization of prostate cancer within the peripheral zone.

Int J Numer Method Biomed Eng 2016 05 22;32(5). Epub 2015 Sep 22.

Department of Computer Science, Aberystwyth University, Aberystwyth, SY23 3DB, UK.

We propose a methodology for prostate cancer detection and localization within the peripheral zone based on combining multiple segmentation techniques. We extract four image features using Gaussian and median filters. Subsequently, we use each image feature separately to generate binary segmentations. Finally, we take the intersection of all four binary segmentations, incorporating a model of the peripheral zone, and perform erosion to remove small false-positive regions. The initial evaluation of this method is based on 275 MRI images from 37 patients, and 86% of the slices were classified correctly with 87% and 86% sensitivity and specificity achieved, respectively. This paper makes two contributions: firstly, a novel computer-aided diagnosis approach, which is based on combining multiple segmentation techniques using only a small number of simple image features, and secondly, the development of the proposed method and its application in prostate cancer detection and localization using a single MRI modality with the results comparable with the state-of-the-art multimodality and advanced computer vision methods in the literature. Copyright © 2015 John Wiley & Sons, Ltd.
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http://dx.doi.org/10.1002/cnm.2745DOI Listing
May 2016

Topological modeling and classification of mammographic microcalcification clusters.

IEEE Trans Biomed Eng 2015 Apr;62(4):1203-14

Goal: The presence of microcalcification clusters is a primary sign of breast cancer; however, it is difficult and time consuming for radiologists to classify microcalcifications as malignant or benign. In this paper, a novel method for the classification of microcalcification clusters in mammograms is proposed.

Methods: The topology/connectivity of individual microcalcifications is analyzed within a cluster using multiscale morphology. This is distinct from existing approaches that tend to concentrate on the morphology of individual microcalcifications and/or global (statistical) cluster features. A set of microcalcification graphs are generated to represent the topological structure of microcalcification clusters at different scales. Subsequently, graph theoretical features are extracted, which constitute the topological feature space for modeling and classifying microcalcification clusters. k-nearest-neighbors-based classifiers are employed for classifying microcalcification clusters.

Results: The validity of the proposed method is evaluated using two well-known digitized datasets (MIAS and DDSM) and a full-field digital dataset. High classification accuracies (up to 96%) and good ROC results (area under the ROC curve up to 0.96) are achieved. A full comparison with related publications is provided, which includes a direct comparison.

Conclusion: The results indicate that the proposed approach is able to outperform the current state-of-the-art methods. Significance: This study shows that topology modeling is an important tool for microcalcification analysis not only because of the improved classification accuracy but also because the topological measures can be linked to clinical understanding.
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http://dx.doi.org/10.1109/TBME.2014.2385102DOI Listing
April 2015

The effects and mechanism of miR-92a and miR-126 on myocardial apoptosis in mouse ischemia-reperfusion model.

Cell Biochem Biophys 2014 Dec;70(3):1901-6

Department of Cardiology, Yiwu Hospital of Wenzhou Medical University (Yiwu Central Hospital), Yiwu, 322000, Zhejiang, People's Republic of China,

Our objective was to explore the effects of miR-92a and miR-126 on myocardial apoptosis in mouse ischemia-reperfusion model and further investigate the underlying mechanisms. Eighteen Kunming mice were selected and randomly divided into sham operation group and ischemia-reperfusion group with nine mice in each group. Cardiac muscle tissue was stained with Evans blue to confirm myocardial infarction and ischemia. Annexin V/PI double staining was used to detect the apoptotic rate of myocardial cells, and terminal-deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) was used to detect the number of apoptotic cells; Western blot was used to detect expression of Caspase 3 to evaluate the apoptosis of mouse myocardial cells; qRT-PCR was used to detect expression of miR-92a and miR-126 in mouse myocardium, and Western blot was used to detect expression of HSP70 in two groups. Evans blue staining results showed that there was a large area of ischemia in myocardium of ischemia-reperfusion mice with marked infarction, suggesting successful establishment of the model. In sham operation group, myocardial cells were mostly normal cells. Annexin V/PI double staining of flow cytometry result showed that the apoptotic rate was 5.9 % in sham operation group and 37.0 % in ischemia-reperfusion group, respectively. Apoptosis detection results showed that apoptotic index (AI) of myocardial cells in ischemia-reperfusion mice was significantly higher than in sham operation group. In addition, qRT-PCR results showed that miR-92a expression in ischemia-reperfusion group was significantly higher than in sham operation group (F = 32.302, P = 0.000), and miR-126 expression in ischemia-reperfusion group was significantly lower than in sham operation group (F = 41.125, P = 0.000). Moreover, HSP70 detected by Western blot showed that HSP expression in ischemia-reperfusion group was significantly lower than in sham operation group. The change of miR-92a was in accordance with AI of myocardial cells. However, the change of miR-126 is in contrary with AI of myocardial cells, which may be related to the HSP70 expression in myocardial cells.
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http://dx.doi.org/10.1007/s12013-014-0149-4DOI Listing
December 2014

[Study based on ICA of "dorsal attention network" in patients with temporal lobe epilepsy].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2010 Feb;27(1):10-5

Department of Medical Imaging, Nanjing General Hospital of Nanjing Military Command, Nanjing 210002, China.

Many functional magnetic resonance imaging (fMRI) studies have revealed the deactivation phenomenon of default mode network in the patients with epilepsy; however, nearly not any of the reports has focused on the dorsal attention network of epilepsy. In this paper, independent component analysis (ICA) was used to isolate the dorsal attention network of 16 patients with temporal lobe epilepsy (TLE) and of 20 healthy normals; and a goodness-of-fit analysis was applied at the individual subject level to choose the interesting component. Intra-group analysis and inter-group analysis were performed. The results indicated that the dorsal attention network included bilateral intraparietal sulcus, middle frontal gyrus, human frontal eye field, posterior lobe of right cerebellum, etc. The TLE group showed decreased functional connectivity in most of the dorsal attention regions with the predominance in the bilateral intraparietal sulcus, middle frontal gyrus, and posterior lobe of right cerebellum. These data suggested that the intrinsic organization of the brain function might be disrupted in TLE. In addition, the decrease of goodness-of-fit scores suggests that activity in the dorsal attention network may ultimately prove a sensitive biomarker for TLE.
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February 2010
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