Ischemic Vascular Disease Research Articles

Secreted Factors from Stem Cells of Human Exfoliated Deciduous Teeth Directly Activate Endothelial Cells to Promote All Processes of Angiogenesis.

Diabetes is a major risk factor for atherosclerosis and ischemic vascular diseases. Recently, regenerative medicine is expected to be a novel therapy for ischemic diseases. Our previous studies have reported that transplantation of stem cells promoted therapeutic angiogenesis for diabetic neuropathy and ischemic vascular disease in a paracrine manner, but the precise mechanism is unclear. Therefore, we examined whether secreted factors from stem cells had direct beneficial effects on endothelial cells to promote angiogenesis. The soluble factors were collected as conditioned medium (CM) 48 h after culturing stem cells from human exfoliated deciduous teeth (SHED) in serum-free DMEM. SHED-CM significantly increased cell viability of human umbilical vein endothelial cells (HUVECs) in MTT assays and accelerated HUVECs migration in wound healing and Boyden chamber assays. In a Matrigel plug assay of mice, the migrated number of primary endothelial cells was markedly increased in the plug containing SHED-CM or SHED suspension. SHED-CM induced complex tubular structures of HUVECs in a tube formation assay. Furthermore, SHED-CM significantly increased neovascularization from the primary rat aorta, indicating that SHED-CM stimulated primary endothelial cells to promote comprehensive angiogenesis processes. The angiogenic effects of SHED-CM were the same or greater than the effective concentration of VEGF. In conclusion, SHED-CM directly stimulates vascular endothelial cells to promote angiogenesis and is promising for future clinical application.

C1q/TNF-Related Protein 9 Promotes Revascularization in Response to Ischemia via an eNOS-Dependent Manner

Strategies to promote revascularization are valuable for ischemic cardiovascular disease. Although C1q/TNF-related protein (CTRP) 9 is an adiponectin paralog with protective properties against cardiometabolic disorders, the role of endogenous CTRP9 in endothelial function is largely unknown. This study aimed to investigate the effects of CTRP9 on revascularization processes and dissected the potential mechanisms. CTRP9-knockout (KO) and wild-type (WT) mice were subjected to unilateral hindlimb ischemic surgery. CTRP9-KO mice exhibited impaired blood flow recovery and decreased capillary density in the ischemic limb compared with WT mice. In both CTRP9-KO and WT mice, systemic delivery of an adenoviral vector expressing CTRP9 (Ad-CTRP9) accelerated blood flow recovery. Treatment with recombinant CTRP9 protein increased network formation and migration of cultured human umbilical vein endothelial cells (HUVECs). CTRP9 promoted the phosphorylation of AMP-activated kinase (AMPK), Akt, and endothelial nitric oxide synthase (eNOS) in HUVECs. CTRP9-KO mice also showed reduced phosphorylation levels of AMPK, Akt, and eNOS in the ischemic limbs compared with WT mice. Furthermore, blockade of AMPK or Akt signaling pathway reversed the CTRP9-stimulated eNOS phosphorylation in HUVECs. Treatment with the NOS inhibitor significantly reduced CTRP9-stimulated network formation and migration of HUVECs. Of note, Ad-CTRP9 had no effects on blood flow of the ischemic limb in eNOS-KO mice. These results indicated that CTRP9 promotes endothelial cell function and ischemia-induced revascularization through the eNOS-dependent mechanism, suggesting that CTRP9 represents a target molecule for treatment of ischemic vascular diseases.

Morphological landscape of endothelial cell networks reveals a functional role of glutamate receptors in angiogenesis

Angiogenesis plays a key role in several diseases including cancer, ischemic vascular disease, and Alzheimer’s disease. Chemical genetic screening of endothelial tube formation provides a robust approach for identifying signalling components that impact microvascular network morphology as well as endothelial cell biology. However, the analysis of the resulting imaging datasets has been limited to a few phenotypic features such as the total tube length or the number of branching points. Here we developed a high content analysis framework for detailed quantification of various aspects of network morphology including network complexity, symmetry and topology. By applying our approach to a high content screen of 1,280 characterised drugs, we found that drugs that result in a similar phenotype share the same mechanism of action or common downstream signalling pathways. Our multiparametric analysis revealed that a group of glutamate receptor antagonists enhances branching and network connectivity. Using an integrative meta-analysis approach, we validated the link between these receptors and angiogenesis. We further found that the expression of these genes is associated with the prognosis of Alzheimer’s patients. In conclusion, our work shows that detailed image analysis of complex endothelial phenotypes can reveal new insights into biological mechanisms modulating the morphogenesis of endothelial networks and identify potential therapeutics for angiogenesis-related diseases.

Attention and Functional Connectivity Among Patients With Early-Stage Subcortical Ischemic Vascular Disease and Alzheimer's Disease.

The current study compared attention profiles and functional connectivity of frontal regions in patients with early-stage subcortical ischemic vascular disease (SIVD) and Alzheimer’s disease (AD). Twenty patients with SIVD, 32 patients with AD, and 23 subjects with normal cognition (NC) received cognition and resting-state functional MRI (rs-fMRI) evaluations. The Cognitive Abilities Screening Instrument (CASI) was used to assess global cognition, and simple attention, processing speed, divided attention, and vigilance/sustained attention were evaluated using the Digit Span Forward, Trail Making Test, Symbol Digit Modality Test, and Conners Continuous Performance Test, respectively. Voxel-based regional homogeneity (ReHo) derived from rs-fMRI data was analyzed to identify significant clusters, which were further correlated with attention profiles. Although the patients with SIVD and AD had comparable global cognitive ability, those with SIVD exhibited worse divided attention and vigilance/sustained attention than those with AD. Compared with the NC group, the patients with SIVD exhibited decreased ReHo within the right middle frontal gyrus (MFG) and left anterior cingulate gyrus (ACG), whereas the patients with AD exhibited increased ReHo within the right orbital part of frontal regions. Correlations between these three clusters with attention exhibited distinct patterns according to the dementia subtype, as did attention indices with significance in predicting global cognition. In summary, our study suggested that worse attention performance was associated with functional disconnection within the frontal regions among patients with SIVD than in those with AD. Frontal functional disconnection may underlie the pathogenesis responsible for defective divided attention, vigilance/sustained attention, and notable within-group variations identified in SIVD.

Expansion and Evaluation of Pharmacist Services in Primary Care.

Challenges with primary care access and overextended providers present opportunities for pharmacists as patient care extenders for chronic disease management. The primary objective was to align primary care pharmacist services with organizational priorities and improve patient clinical outcomes. The secondary objective was to develop a technological strategy for service evaluation. An interdisciplinary workgroup developed primary care pharmacist services focused on improving performance measures and supporting the care team in alignment with ongoing population health initiatives. Pharmacist collaborative practice agreements (CPAs) were developed and implemented. An electronic dashboard was developed to capture service outcome measures. Blood pressure control to <140/90 mmHg was achieved in 74.15% of patients who engaged with primary care pharmacists versus 41.53% of eligible patients electing to follow usual care pathways. Appropriate statin use was higher in patients engaged with primary care pharmacists than in eligible patients electing to follow usual care pathways both for diabetes and ischemic vascular disease (12.4% and 2.2% higher, respectively). Seventeen of 54 possible process and outcome measures were identified and incorporated into an electronic dashboard. Primary care pharmacist services improve hypertension control and statin use. Service outcomes can be measured with discrete data from the electronic health record (EHR), and should align with organizational priorities.

Preventive Care and Chronic Disease Management Comparison of Appalachian and Non-Appalachian Community Health Centers in the United States.

IntroductionThe Appalachian region is often characterized by poor health outcomes and economic depression. Health centers (HCs) are community-based and patient-directed organizations that deliver comprehensive, culturally competent, high-quality primary healthcare services in high need areas, including Appalachia, where economic, geographic, or cultural factors can hinder access to healthcare services.PurposeThe study compares the clinical quality performance in preventive care and chronic disease management between Appalachian HCs and their non-Appalachian counterparts.MethodsUsing 2015 Uniform Data System (UDS) health center data, bivariate and multivariate linear regression analyses examine the association of Appalachian HC with performance on preventive and chronic care clinical quality measures (CQMs).ResultsIn the multivariate analysis, patients served at Appalachian HCs are more likely to receive colorectal cancer screening and pediatric weight assessment and counseling than at non-Appalachian HCs. No statistically significant differences in performance observed among other CQMs. The percentage of Medicaid patients and total physician FTEs have positive associations with preventive care in colorectal and cervical cancer screening, pediatric weight assessment and counseling, and tobacco screening and cessation intervention as well as chronic disease management of aspirin therapy for ischemic vascular disease and hypertension control in the multivariate model.ImplicationsOverall Appalachian HCs perform as well as or better than non-Appalachian HCs in delivering preventive and chronic care services. Further examination of clinical quality improvement programs, insurance payer mix, and practice size among Appalachian HCs could advance the replication of clinical quality success for clinics in similar underserved communities.

A novel selective PPARα modulator, pemafibrate promotes ischemia-induced revascularization through the eNOS-dependent mechanisms.

Cardiovascular disease is a leading cause of death worldwide. Obesity-related metabolic disorders including dyslipidemia cause impaired collateralization under ischemic conditions, thereby resulting in exacerbated cardiovascular dysfunction. Pemafibrate is a novel selective PPARα modulator, which has been reported to improve atherogenic dyslipidemia, in particular, hypertriglyceridemia and low HDL-cholesterol. Here, we investigated whether pemafibrate modulates the revascularization process in a mouse model of hindlimb ischemia. Male wild-type (WT) mice were randomly assigned to two groups, normal diet or pemafibrate admixture diet from the ages of 6 weeks. After 4 weeks, mice were subjected to unilateral hindlimb surgery to remove the left femoral artery and vein. Pemafibrate treatment enhanced blood flow recovery and capillary formation in ischemic limbs of mice, which was accompanied by enhanced phosphorylation of endothelial nitric oxide synthase (eNOS). Treatment of cultured endothelial cells with pemafibrate resulted in increased network formation and migratory activity, which were blocked by pretreatment with the NOS inhibitor NG-nitro-L-arginine methyl ester (L-NAME). Pemafibrate treatment also increased plasma levels of the PPARα-regulated gene, fibroblast growth factor (FGF) 21 in WT mice. Systemic administration of adenoviral vectors expressing FGF21 (Ad-FGF21) to WT mice enhanced blood flow recovery, capillary density and eNOS phosphorylation in ischemic limbs. Treatment of cultured endothelial cells with FGF21 protein led to increases in endothelial cell network formation and migration, which were canceled by pretreatment with L-NAME. Furthermore, administration of pemafibrate or Ad-FGF21 had no effects on blood flow in ischemic limbs in eNOS-deficient mice. These data suggest that pemafibrate can promote revascularization in response to ischemia, at least in part, through direct and FGF21-mediated modulation of endothelial cell function. Thus, pemafibrate could be a potentially beneficial drug for ischemic vascular disease.

Telehealth Use among Community Health Centers and Cardio-Metabolic Health Outcomes.

Public health interventions to manage the cardio-metabolic syndrome (CMS) have had modest success, necessitating the expansion of telehealth services to where people live. This effort analyzes the association between telehealth provision and the management of CMS-related quality measures (hypertension, diabetes, weight assessment and related counseling, lipid therapy for coronary artery disease, and antiplatelet therapy for ischemic vascular disease) using the Uniform Data System administrative database during the period 2016–2018. A total of 523, 600, and 586 community health centers (CHCs) were documented using telehealth, out of the 1367, 1373, and 1362 total CHCs, in the respective three years. Our primary analysis showed that there was no association between telehealth use and the outcomes. A difference in difference approach that compared the CHCs which transitioned from not using it to using it with those that did not use telehealth in two consecutive years also produced null results. However, among rural areas, the odds of better managing the outcomes were greater for certain outcomes. Our study provides limited support that the adoption of telehealth is potentially beneficial in improving certain outcomes in the CHCs setting that are based in rural areas. More specificity in data regarding the nature of telehealth implementation in the CHC setting could bring clarity in these associations.

Cerebrospinal Fluid Biomarkers to Differentiate Idiopathic Normal Pressure Hydrocephalus from Subcortical Ischemic Vascular Disease.

Idiopathic normal pressure hydrocephalus (iNPH) remains a challenge to differentiate from subcortical ischemic vascular disease (SIVD). Despite major research efforts, the cerebrospinal fluid (CSF) biomarker profiles of the two diseases are still not known in detail. To determine if novel CSF biomarkers, neurofilament light (NFL) reflecting axonal damage, the synaptic protein neurogranin (NG), and the astroglial marker chitinase-3-like protein 1 (YKL-40), and the core Alzheimer's disease (AD) biomarkers, amyloid-β 42 (Aβ42), total tau (t-tau), phosphorylated tau (p-tau), can differentiate iNPH from SIVD. Patients with AD and healthy controls (HC) were included for comparison purposes. Patients with iNPH (n = 28), SIVD (n = 30), AD (n = 57), and HC (n = 33) were retrospectively included from the Danish Dementia Biobank. All patients with iNPH had effect of shunt surgery with a follow-up period of 4 to 69 months. CSF biomarkers were measured using immunoassays. Lower levels of NFL, NG, Aβ42, and t-tau were found in patients with iNPH versus SIVD, while YKL-40 and p-tau were similar in the two diseases. NFL and Aβ42 were the most reliable biomarkers to differentiate iNPH from SIVD with an area under the curve (AUC) on 0.82 and 0.80, respectively. Combining NFL with Aβ42, t-tau, and p-tau resulted in an AUC of 0.90, which was equivalent to the diagnostic accuracy of all six biomarkers combined. An addition of NFL to the CSF panel of Aβ42, t-tau, and p-tau may improve the differentiation of iNPH from SIVD.

P0580ACUTE INTERSTITIAL NEPHRITIS RELATED TO EMPAGLIFLOZIN

Abstract Background and Aims SGLT-2 inhibitors are effective anti-hyperglycemic agents with proved cardiovascular and renal benefits. However, there have been post marketing reports of episodes of acute kidney injury (AKI), some requiring hospitalization and even dialysis in patients receiving SGLT2 inhibitors. This phenomenon may be related to volume contraction and hemodynamic changes, particularly in patients with other risk factors (such as patients on RAAS blocking agents or NSAIDS, patients with CKD). We present a case of acute interstitial nephritis (AIN) and acute tubular necrosis related to an SGLT2-inhibitor. Method Case report description. Results A 67-year-old women was admitted with weakness, dizziness and abdominal pain. Her medical history was remarkable for hypertension, diabetes mellitus, ischemic heart disease and peripheral vascular disease. Her medications included bisoprolol, losartan, amlodipine, sitagliptin and aspirin. Two months prior the current presentation, empagliflozin was prescribed by her primary physician for her diabetes mellitus. However, several days after initiation of empgliflozin she felt weak and dizzy and empagliflozin was discontinued. A week before the current presentation, empagliflozin was re-initiated by her cardiologist. The patient reported no recent illness, fevers, rash, arthralgias, respiratory symptoms or bone pain. She denied exposure to other new medications (including NSAIDS and antibiotics). On admission, blood pressure was 165/76 mm Hg. The rest of the physical examination was unremarkable. Laboratory studies revealed acute kidney injury (creatinine 3.19 mg/dL, BUN 28 mg/dL, baseline creatinine 0.9 mg/dL). Complete blood count demonstrated no eosinophilia or thrombocytopenia. Urinalysis showed a few leukocytes but no red cells or casts. The urine protein to creatinine ratio was 5160 mg of protein per gram creatinine. Abdominal ultrasonography showed normal-size kidneys and no hydronephrosis. Immunologic and infectious serologies were unremarkable. over several days the patient became oligo-anuric and creatinine peaked to 9.22 mg/dL and hemodialysis was initiated. Empiric treatment with prednisone was given and a renal biopsy was performed. Four glomeruli were seen on light microscopy. The glomeruli were normocellular. An interstitial infiltrate of lymphocytes and small numbers of eosinophils were seen. Thining of the renal tubular brush border with intra-tubular necrotic content was a also seen. Immunofluorescence was negative. The findings were compatible with acute interstitial nephritis and acute tubular necrosis (Figure 1). The patient was discharged with a regimen of intermittent hemodialysis and steroid therapy. Three months later, urine output and kidney function improved, and the patient was weaned off dialysis. Conclusion In this case report, we describe previously unreported histologically proven AIN likely related to empagliflozin exposure. Although SGLT2 inhibitors have been reported to be associated with AKI it has been supposed to be related to volume contraction and hemodynamic changes. As virtually any drug can cause AIN, further proof of the drug's causation in our case was an onset of renal dysfunction with re- institution of empagliflozin, biopsy-proven AIN and absence of other drugs, infection or systemic disease that might cause AIN. With the dramatic increase in use of SGLT-2 inhibitors worldwide, treating physicians should be aware of AIN as a possible cause of AKI in this context.

P1527SURVIVAL COMPARISON:HEMODIALYSIS VS PERITONEAL DIALYSIS: TEN YEARS OBSERVATIONAL STUDY

Abstract Background and Aims Survival comparison between peritoneal dialysis (PD) and hemodialysis (HD) is still controversial. While some retrospective studies have shown better survival in PD, particularly in the first year, others have not identified this difference. The only RCT published so far showed a 3-year mortality rate similar between two groups. However, the number of patients was too small to provide sufficient statistical power to identify any survival differences between the two dialysis techniques. Aim of this study was to compare HD and PD in term of survival rate and factors possibly involved in a ten-years observational study. Method We retrospectively evaluated all the incident patients that started a dialytic treatment, either HD or PD, due to uremia from 01-01-2008 to 31-12-2018 at the U.O. Nephrology ASST Spedali Civili of Brescia. Exclusion criteria were: duration of dialysis treatment less than 3 months, and previous dialytic treatment or kidney transplantation. For each patient anthropometric, clinical-anamnestic data and comorbidities at dialysis start were recorded. Results One thousand and six patients were identified. 130 patients were excluded due to dialysis treatment less than 3 months. A total 876 patients were analyzed. 77% of patients started dialysis on HD while 23% chose PD. Age was significantly higher in HD patients (69±15 vs 65±16 years; p&amp;lt;0.05). No differences were found in the incidence of: ischemic heart disease (HD 24%, PD 25%, p=0.90), diabetes (32% vs 32%, p=0.83), cancer (20% vs 17%, p=0.37), cardiac arrhythmia (20% vs 25%, p=0.08) and peripheral vascular disease (25% vs 25%, p=0.89). An increased incidence of COPD (HD 17% vs PD 8%, p&amp;lt;0.05) and hypertension (73% vs 87%, p&amp;lt;0.05) was present in PD patients. During follow-up, 17% of patients treated with PD shifted to HD due to catheter malfunction, recurrent infections, insufficient dialytic adequacy or ultrafiltration failure. Kidney transplants were performed more frequently in PD patients (HD 12%; PD 24%, p&amp;lt;0.05). At an intention to treat analysis of the data, univariate analysis showed better survival in PD patients (p&amp;lt;0.05, Figure 1). This difference was not confirmed at multivariate analysis (Figure 2), where age, cardiac arrhythmia, cirrhosis, diabetes and peripheral vascular disease were independently associated with an increased risk of mortality. No independent influence on mortality of the dialysis treatment modality was found. Conclusion This ten years observational study shows that HD and PD are similar in term of patient survival. Age and comorbidities seem to play the most important role in patient survival.

Reduced expression of microRNA-130a promotes endothelial cell senescence and age-dependent impairment of neovascularization.

Aging is associated with impaired neovascularization in response to ischemia. MicroRNAs are small noncoding RNAs emerging as key regulators of physiological and pathological processes. Here we investigated the potential role of microRNAs in endothelial cell senescence and age-dependent impairment of neovascularization. Next generation sequencing and qRT-PCR analyses identified miR-130a as a pro-angiogenic microRNA which expression is significantly reduced in old mouse aortic endothelial cells (ECs). Transfection of young ECs with a miR-130a inhibitor leads to accelerated senescence and reduced angiogenic functions. Conversely, forced expression of miR-130a in old ECs reduces senescence and improves angiogenesis. In a mouse model of hindlimb ischemia, intramuscular injection of miR-130a mimic in older mice restores blood flow recovery and vascular densities in ischemic muscles, improves mobility and reduces tissue damage. miR-130a directly targets antiangiogenic homeobox genes MEOX2 and HOXA5. MEOX2 and HOXA5 are significantly increased in the ischemic muscles of aging mice, but forced expression of miR-130a reduces the expression of these factors. miR-130a treatment after ischemia is also associated with increased number and improved functional activities of pro-angiogenic cells (PACs). Forced expression of miR-130a could constitute a novel strategy to improve blood flow recovery and reduce ischemia in older patients with ischemic vascular diseases.

Identification of Metal-Binding Peptides and Their Conjugation onto Nanoparticles of Superparamagnetic Iron Oxides and Liposomes.

Metallic materials are used for clinical medical devices such as vascular stents and coils to treat both ischemic and hemorrhagic vascular diseases. An antiplatelet drug is required to avoid thromboembolic complication until metallic surface is covered with a neo-endothelial cell layer. It is important to identify endothelial cell coverage on the metallic surface. However, it is difficult since there are no selective ligands. Here, we used the phage display method to identify peptide ligands that had high affinity for the metallic surface of Ni-Ti stents, Pt-W coils, and Co-Cr stents. The binding assay using fluorescence labeling revealed that several synthetic peptides could bind onto those surfaces. We also chose some oligopeptides for the conjugation onto superparamagnetic iron oxide (SPIO) nanoparticles and liposome-encapsulating SPIO nanoparticles and studied their ability to bind to the stent and coils. By SEM and fluorophotometry, we found that those modified SPIOs and liposomes were selectively bound onto those surfaces. In addition, both treated stents and coils could be detected by magnetic resonance imaging due to the magnetic artifact through the SPIOs and liposomes that were immobilized onto the surface. Thus, we identified metal-binding peptides which may enable to stop antiplatelet therapy after vascular stenting or coiling.

Targeting Angiotensin-Converting Enzyme-2/Angiotensin-(1-7)/Mas Receptor Axis in the Vascular Progenitor Cells for Cardiovascular Diseases.

Bone marrow-derived hematopoietic stem/progenitor cells are vasculogenic and play an important role in endothelial health and vascular homeostasis by participating in postnatal vasculogenesis. Progenitor cells are mobilized from bone marrow niches in response to remote ischemic injury and migrate to the areas of damage and stimulate revascularization largely by paracrine activation of angiogenic functions in the peri-ischemic vasculature. This innate vasoprotective mechanism is impaired in certain chronic clinical conditions, which leads to the development of cardiovascular complications. Members of the renin-angiotensin system-angiotensin-converting enzymes (ACEs) ACE and ACE2, angiotensin II (Ang II), Ang-(1-7), and receptors AT1 and Mas-are expressed in vasculogenic progenitor cells derived from humans and rodents. Ang-(1-7), generated by ACE2, is known to produce cardiovascular protective effects by acting on Mas receptor and is considered as a counter-regulatory mechanism to the detrimental effects of Ang II. Evidence has now been accumulating in support of the activation of the ACE2/Ang-(1-7)/Mas receptor pathway by pharmacologic or molecular maneuvers, which stimulates mobilization of progenitor cells from bone marrow, migration to areas of vascular damage, and revascularization of ischemic areas in pathologic conditions. This minireview summarizes recent studies that have enhanced our understanding of the physiology and pharmacology of vasoprotective axis in bone marrow-derived progenitor cells in health and disease. SIGNIFICANCE STATEMENT: Hematopoietic stem progenitor cells (HSPCs) stimulate revascularization of ischemic areas. However, the reparative potential is diminished in certain chronic clinical conditions, leading to the development of cardiovascular diseases. ACE2 and Mas receptor are key members of the alternative axis of the renin-angiotensin system and are expressed in HSPCs. Accumulating evidence points to activation of ACE2 or Mas receptor as a promising approach for restoring the reparative potential, thereby preventing the development of ischemic vascular diseases.

Intensive Care Unit Approach to the Diagnosis of Brain Death in Infratentorial Neurologic Pathology: Case Reports

The ischemic and primary vascular injury of the brainstem (BS) can determine, among other serious conditions, the brain death (BD) of the individual. We present 2 cases of individuals with primary ischemic vascular disease of the BS who evolved to BD and were donors of solid organs and tissues. In both cases, the clinical examination was positive for the diagnosis of BD, and transcranial Doppler did not confirm the pattern of cerebral circulatory arrest that accompanies BD. The magnetic resonance angiography performed on 1 patient confirmed the lesion etiology and the presence of vascular obstruction. Both patients were real and effective organ and tissue donors. In these cases, we suggest not to resort to transcranial Doppler as an auxiliary diagnostic test.

Arrb2 promotes endothelial progenitor cell-mediated postischemic neovascularization.

Background and aim: Modulating biological functions of endothelial progenitor cells (EPCs) is essential for therapeutic angiogenesis in ischemic vascular diseases. This study aimed to explore the role and molecular mechanisms of β-arrestin 2 (Arrb2) in EPCs biology and angiogenic therapy.Methods: The influence of Arrb2 on postischemic neovascularization was evaluated in Arrb2-deficient mice. The proliferation, apoptosis, and various functions of EPCs were analyzed in vitro by manipulating the expression of Arrb2. Finally, the in vivo effect of Arrb2 on EPC-mediated neovascularization was investigated in a mouse model of hind-limb ischemia (HLI).Results: Arrb2-deficient mice exhibited impaired blood flow recovery based on laser Doppler measurements and reduced capillary density in the adductor muscle after unilateral HLI. Arrb2-deficient mice also showed restricted intraplug angiogenesis in subcutaneously implanted Matrigel plugs. In vitro, lentivirus-mediated Arrb2 overexpression promoted EPC proliferation, migration, adhesion, and tube formation, whereas Arrb2 knockdown had opposite effects. In addition, the overexpression of Arrb2 in EPCs protected them from hypoxia-induced apoptosis and improved intraplug angiogenesis ex vivo. Mechanistically, Arrb2 interacted with and activated extracellular signal-regulated kinase (ERK)1/2 and protein kinase B (Akt) signaling pathways. Finally, the transplantation of EPCs overexpressing Arrb2 resulted in a significantly higher blood flow restoration in ischemic hind limb and higher capillary density during histological analysis compared with control or Arrb2-knockdown EPC-treated nude mice.Conclusions: The data indicated that Arrb2 augmented EPC-mediated neovascularization through the activation of ERK and Akt signaling pathways. This novel biological function of Arrb2 might provide a potential therapeutic option to promote EPCs in the treatment of ischemic vascular diseases.

The comparative study between thromboelastography and conventional coagulation tests in ischemic cerebral vascular disease

Objective To explore the correlation and consistency between thromboelastography (TEG) and traditional coagulation tests (CCTs) in ischemic cerebral vascular disease (ICVD). Methods Totally 108 ICVD patients admitted to Nanyang Central Hospital from May 1 to October 31 2018 were enrolled. Patients’ TEG parameters (R value, K value, Angle value, MA value, CI value and G value) and CCTs parameters (PT, APTT, TT, and FIB) were collected and analyzed retrospectively. The Spearman correlation coefficient was used to explore the correlation between TEG and CCTs parameters, and Kappa (κ) to explore the consistency in determining the coagulation status of the patients. The ROC curve was used to analyze the predictive value of TEG parameters for abnormal results of CCTs, and the results of TEG and CCTs were comprehensively analyzed to evaluate the ability to predict the coagulation status of patients. Results (1) PLT was positively correlated with MA value and G value; PT and APTT were positively correlated with K value; TT was positively correlated with R value and K value; FIB was positively correlated with Angle value, MA value and G value. TT was negatively correlated with Angle value and CI value; FIB was negatively correlated with K value. (2) PT and MA values, PT and G values, FIB and MA values, FIB and G values were accordant in valuing the hypoxic state of ICVD patients. (3) PLT and Angle values, PLT and MA values, PLT and CI values, PLT and G values were accordant in assessing hypercoagulable status of ICVD patients; FIB and Angle values, FIB and MA values, FIB and CI value, and FIB and G value were consistent in evaluating the hypercoagulable state of ICVD patients. (4) For detecting TT>20 s, the AUC of K value and Angle value were 0.648, 0.651, respectively; For detecting FIB>4 g/L, the AUC of Angle value and MA value were 0.717 and 0.747, respectively; For detecting PLT>300×109/L, the AUC of MA value was 0.808 (all P<0.05). Conclusions There is weak correlation and consistency between TEG and CCTs parameters in ICVD patients. The TEG parameters have good predictive value in evaluating the abnormal results of CCTs, but cannot replace the CCTs. Combination of these two methods can better reflect the coagulation status of patients, so as to afford assistance. Key words: Thromboelastography; Conventional coagulation tests; Ischemic cerebral vascular disease; Ischemic stroke; Comparation

Study on the association between ambient air pollution and daily cardiovascular death in Hefei, China.

Cardiovascular disease has always been the most serious public health problem in China. Although many studies have found that the risk of death caused by cardiovascular disease is related to air pollutants, the existing results are still inconsistent. The aim of this study was to investigate the effects of air pollutants on the risk of daily cardiovascular deaths in Hefei, China. Daily data on cardiovascular deaths, daily air pollutants, and meteorological factors from 2007 to 2016 were collected in this study. A time-series study design using a distributed lag nonlinear model was employed to evaluate the association between air pollutants and cardiovascular deaths. First, a single air pollutant model was established based on the minimum value of Akaike information criterion (AIC), and the single day lag effects and multi-day lag effects were discussed separately. Then, two-pollutant models were fitted. Subgroup analyses were conducted by gender (male and female), age (< 65 age and ≥ 65 age), and disease type (ischemic heart disease and cerebral vascular disease). There were 34,500 cases of cardiovascular deaths during the period 2007-2016, and the average concentrations of air pollutants (PM10, SO2, NO2, PM2.5, CO, O3) were 106.11, 20.34, 30.49, 72.59, 958.7, and 67.88 μg/m3, respectively. An increase of interquartile range (IQR) in PM10, SO2, NO2, PM2.5, CO, and O3 were associated with an increase of 4.34% (95%CI 1.54~7.23%) at lag 0-6, 5.79% (95%CI 2.43~9.27%) at lag 0-5, 4.47% (95%CI 1.64~7.37%) at lag 0-5, 3.14% (95%CI 0.03~6.36%) at lag 0-4, 3.11% (95%CI 0.21~6.10%) at lag 0-3, and 8.17% (95%CI 1.89~14.84%) at lag 0-5 in cardiovascular deaths, respectively. Females, older group (≥ 65 years) and deaths from cerebral vascular disease were more vulnerable to air pollution than males, younger individuals (< 65 years) and deaths from ischemic heart disease. Our results suggest that air pollution increased the risk of cardiovascular deaths in Hefei. These findings can provide evidence for effective air quality interventions in Hefei.

Antithrombotic Management After Intracranial Hemorrhage.

Intracranial hemorrhage remains one of the most feared acute neurological emergencies. However, apart from the acute management, secondary risk factor management and prevention of ischemic events remains ambiguous. We present a thorough review of the current data available regarding management of antithrombotics after intracranial hemorrhage. The most robust evidence comes from the investigators of the RESTART trial which reassured the safety of resuming antiplatelet therapy after ICH, namely in patients with prior indication and treatment with antithrombotics. We conclude that based on available data, the risk of recurrent ICH is probably too small to exceed the found benefits of antiplatelet therapy in the secondary prevention of ischemic vascular disease.

The Mir-99b/Let-7e/Mir-125a cluster Is Associated with Platelet Count and Mean Platelet Volume and Regulates Megakaryocyte Proplatelet Formation

Platelet count (PC) and mean platelet volume (MPV) are critical measurements when considering the role of platelets in hemostasis and thrombosis, abnormalities in PC and MPV have been shown to be predictors of ischemic cardiovascular disease. Ischemic vascular disease has a known genetic component, and we and others have shown high heritability for both PC and MPV. Many inherited, and most immune, thrombocytopenias show an inverse relationship between PC and MPV, and such a relationship has also been reported in healthy subjects. Although genome-wide association studies have identified numerous single nucleotide variants in protein-coding genes associated with PC and MPV (Geiger Nat Genet 2011), non-coding genes have had rather little consideration. The goal of our studies was to identify microRNAs (miRs) regulating PC and MPV and to begin to understand the molecular mechanisms of this inverse platelet number-volume relationship. Initially, we queried our Platelet RNA and Expression-1 data set and observed that PC and MPV are inversely correlated in these 154 healthy subjects (r=-0.45, p=3.98E-09). We next determined which of the 734 platelet-expressed miRs were significantly (p&lt;0.05) correlated with both PC and MPV. Of these miRs, only miR-125a-5p, miR-99b-5p, let-7e-5p and miR-150-5p had an inverse relationship with PC and MPV. The Table shows the correlations between these miRs and complete blood count data. Subsequent studies focused on miR-125a-5p, miR-99b-5p, let-7e-5p because they (1) were associated with only platelet parameters and not WBC or Hb, (2) were more highly expressed than miR-150-5p and (3) showed the same directionality (e.g., positive r value for PC). We were also intrigued by the fact that these 3 miRs exist as a genomic cluster within 727 bp on chr19q13.41. The expression of each of the 3 miRs in this cluster was strongly correlated with each other in platelets (r=0.93, p=1.02E-68 for miR-125a and let-7e; r=0.91, p=8.53E-61 for miR-99b and let-7e; r=0.89, p=1.19E-52 for miR-125a and miR-99b), consistent with a single, polycistronic transcript containing all genes. To begin to address the potential functionality of this miR cluster, we overexpressed and knocked down their expression in megakaryocytes (MKs), since MK proplatelet formation (PPF) is a necessary step in the generation of peripheral blood platelets. We utilized human umbilical cord blood derived CD34-positive hematopoietic stem and progenitor cells differentiated along the MK lineage with thrombopoietin. Quantification of miR levels with qPCR demonstrated all 3 miRs in the cluster progressively increased from culture day 6 to day 9 to day 13 (the time during which MKs mature in culture). Compared to a scrambled control, when miR activity was knocked down with locked nucleic acids (LNAs), we observed a 61% reduction in PPF for miR-125a-5p (p&lt;0.05), a 54% reduction for let-7e-5p (p&lt;0.05) and a ~28% reduction for miR-99b-5p (p=0.33). PPF was quantified blinded as to treatment group. When all 3 miRs in the cluster were inhibited simultaneously by LNAs, we observed a 74% reduction in PPF (p&lt;0.05) (Figure 1). LNA inhibition of two miRs not associated with PC or MPV did not alter MK PFF. To date, we have only tested the effect of overexpression of one miR, but observed that lentiviral overexpression of miR-125a-5p induced an increase in MK PPF (p&lt;0.05). In summary, we have identified a genomic cluster of miRs (miR-99b/let-7e/miR-125a) that regulates PPF in cultured human MKs and whose expression is positively correlated with human PC and negatively correlated with MPV. We speculate that platelet mass homeostasis, which is determined by PC and MPV, may be controlled in part by this novel genomic locus. Disclosures No relevant conflicts of interest to declare.